Patent Publication Number: US-11387264-B2

Title: Solid-state imaging device and manufacturing method

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application is a national stage application under 35 U.S.C. 371 and claims the benefit of PCT Application No. PCT/JP2017/040043 having an international filing date of 7 Nov. 2017, which designated the United States, which PCT application claimed the benefit of Japanese Patent Application No. 2016-225960 filed 21 Nov. 2016, the entire disclosures of each of which are incorporated herein by reference. 
     TECHNICAL FIELD 
     The present technology relates to a solid-state imaging device and a manufacturing method, and especially relates to a solid-state imaging device and a manufacturing method capable of suppressing reflection of incident light in a wide wavelength band. 
     BACKGROUND ART 
     Solid-state imaging devices are required to be made small and to have multiple pixels, so that reduction of pixels is being promoted. However, as a pixel size decreases, sensitivity is deteriorated, so that it is required to compensate sensitivity deterioration due to reduction in aperture ratio, and improve the sensitivity. In such solid-state imaging device, since the incident light is reflected on a surface of a Si substrate, intensity of light reaching a light-receiving unit is lost and the sensitivity is deteriorated, and flare and ghost are caused by incident light from an unintended optical path. 
     Therefore, proposed is a technology of effectively suppressing reflection of incident light for all the wavelength regions (all visible light) of the light incident on a light-receiving unit by forming an antireflective layer having an uneven structure (also referred to as a moth-eye structure) corresponding to a wavelength region of the light incident on the light-receiving unit (for example, refer to Patent Document 1). 
     CITATION LIST 
     Patent Document 
     
         
         Patent Document 1: Japanese Patent Application Laid-Open No. 2009-218357 
       
    
     SUMMARY OF THE INVENTION 
     Problems to be Solved by the Invention 
     By the way, in a case of using the moth-eye structure adopted in Patent Document 1 described above, a deep uneven structure at a narrow-pitch is required, but it is technically difficult to realize the same with a thickness of less than about 100 nm, for example, by processing by lithography or dry etching. 
     Furthermore, in a case of using the moth-eye structure, if the thickness of at least about 100 nm cannot be secured, the reflection ratio cannot be sufficiently reduced. 
     The present technology is achieved in view of such a situation, and an object thereof is to suppress the reflection of the incident light in a wide wavelength band. 
     Solutions to Problems 
     A solid-state imaging device according to an aspect of the present technology is provided with a substrate including a photoelectric converting unit in a pixel unit, and a reflection ratio adjusting layer provided on the substrate in an incident direction of incident light with respect to the substrate for adjusting reflection of the incident light on the substrate, in which the reflection ratio adjusting layer includes a first layer formed on the substrate and a second layer formed on the first layer, the first layer has an uneven structure provided on the substrate, and a recess portion on the uneven structure is filled with a material having a lower refractive index than a refractive index of the substrate forming the second layer, and a thickness of the first layer is made a thickness optimized for a wavelength of light to be received. 
     A manufacturing method according to an aspect of the present technology is a manufacturing method of manufacturing a solid-state imaging device provided with a substrate including a photoelectric converting unit in a pixel unit, and a reflection ratio adjusting layer provided on the substrate in an incident direction of incident light with respect to the substrate for adjusting reflection of the incident light on the substrate, the method including forming the reflection ratio adjusting layer including a first layer formed on the substrate and a second layer formed on the first layer, filling a recess portion on an uneven structure provided on the substrate included in the first layer with a material having a lower refractive index than a refractive index of the substrate forming the second layer, and making a thickness of the first layer a thickness optimized for a wavelength of light to be received. 
     In the solid-state imaging device according to an aspect of the present technology, a substrate including a photoelectric converting unit in a pixel unit, and a reflection ratio adjusting layer provided on the substrate in an incident direction of incident light with respect to the substrate for adjusting reflection of the incident light on the substrate are provided. Furthermore, the reflection ratio adjusting layer includes a first layer formed on the substrate and a second layer formed on the first layer, the first layer has an uneven structure provided on the substrate, and a recess portion on the uneven structure is filled with a material having a lower refractive index than that of the substrate forming the second layer, and a thickness of the first layer is made a thickness optimized for a wavelength of light to be received. 
     In the manufacturing method according to an aspect of the present technology, the solid-state imaging device is manufactured. 
     Effects of the Invention 
     According to one aspect of the present technology, reflection of incident light in a wide wavelength band may be suppressed. 
     Note that, the effects herein described are not necessarily limited and may be any of the effects described in the present disclosure. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG. 1  is a view illustrating a configuration of one embodiment of a solid-state imaging device to which the present technology is applied. 
         FIG. 2  is a view for illustrating an uneven structure. 
         FIG. 3  is a view for illustrating a relationship between refractive indices of layers. 
         FIG. 4  is a view for illustrating the uneven structure. 
         FIG. 5  is a view for illustrating diffraction and reflection of incident light. 
         FIG. 6  is a view for illustrating a relationship between a wavelength and a pit P. 
         FIG. 7  is a view for illustrating a relationship between the wavelength and the pit P. 
         FIG. 8  is a view for illustrating arrangement of projected portions. 
         FIG. 9  is a view for illustrating a reflection ratio between layers. 
         FIG. 10  is a view for illustrating a relationship between the wavelength and an effective refractive index. 
         FIG. 11  is a view for illustrating a relationship between the wavelength and a height of a projected portion. 
         FIG. 12  is a view for illustrating a relationship between the wavelength and the height of the projected portion. 
         FIG. 13  is a view for illustrating a relationship between the height of the projected portion and light reflection intensity. 
         FIG. 14  is a view for illustrating a relationship between the wavelength and space occupancy. 
         FIG. 15  is a view for illustrating a spectral characteristic. 
         FIG. 16  is a view for illustrating arrangement of the projected portions. 
         FIG. 17  is a view illustrating an example when a hole array is formed by self assembly. 
         FIG. 18  is a view for illustrating a light intensity reflection ratio in cases with and without the uneven structure. 
         FIG. 19  is a view for illustrating a relationship between the wavelength and the light intensity reflection ratio. 
         FIG. 20  is a view for illustrating a relationship between the wavelength and the light intensity reflection ratio. 
         FIG. 21  is a view for illustrating a relationship between the wavelength and the light intensity reflection ratio. 
         FIG. 22  is a view for illustrating a size of a pixel to be manufactured. 
         FIG. 23  is a view for illustrating a first manufacturing method. 
         FIG. 24  is a view for illustrating a first manufacturing method. 
         FIG. 25  is a view for illustrating a first manufacturing method. 
         FIG. 26  is a view for illustrating a step present between pixels. 
         FIG. 27  is a view for illustrating a structure for reducing the step between the pixels. 
         FIG. 28  is a view for illustrating an example of a gray tone mask. 
         FIG. 29  is a view for illustrating a structure in which an inter-pixel light-shielding wall is provided. 
         FIG. 30  is a view for illustrating a fourth manufacturing method. 
         FIG. 31  is a view for illustrating the fourth manufacturing method. 
         FIG. 32  is a view for illustrating the fourth manufacturing method. 
         FIG. 33  is a view for illustrating a fifth manufacturing method. 
         FIG. 34  is a view for illustrating the fifth manufacturing method. 
         FIG. 35  is a view for illustrating a sixth manufacturing method. 
         FIG. 36  is a view for illustrating the sixth manufacturing method. 
         FIG. 37  is a view for illustrating a relationship between the wavelength and the light intensity reflection ratio. 
         FIG. 38  is a view for illustrating a seventh manufacturing method. 
         FIG. 39  is a view for illustrating the seventh manufacturing method. 
         FIG. 40  is a view for illustrating another structure of the solid-state imaging device. 
         FIG. 41  is a view illustrating an application example of an electronic device to which the solid-state imaging device according to the present technology is applied. 
     
    
    
     MODE FOR CARRYING OUT THE INVENTION 
     A mode for carrying out the present technology (hereinafter, referred to as an embodiment) is hereinafter described. 
     &lt;Configuration Example of Embodiment of Solid-State Imaging Device to which Present Technology is Applied&gt; 
       FIG. 1  is a cross-sectional side view illustrating a configuration example of one embodiment of a solid-state imaging device to which the present technology is applied. 
     A solid-state imaging device  11  in  FIG. 1  is provided with a lens  31 , a color filter  32 , a planarizing film  33 , a light-shielding film  34 , an oxide film (SiO2)  35 , an intermediate second layer  36 , an intermediate first layer  37 , and a Si substrate  38  in this order from an upper portion of the drawing. 
     The solid-state imaging device  11  in  FIG. 1  receives light incident from above in the drawing and generates a pixel signal corresponding to an amount of the received light. 
     In further detail, the lens  31  condenses the incident light into a photoelectric conversion element not illustrated provided in a pixel unit in the Si substrate  38 . Note that, in the drawing, a projected portion upward in the drawing of the lens  31  corresponds to each pixel, and in  FIG. 1 , an example in which three pixels are arranged in a horizontal direction is illustrated. 
     The color filter  32  is a filter which transmits only light of a specific wavelength out of the incident light; for example, this extracts light of a wavelength corresponding to any one of red, green, and blue (RGB) and transmits the same to a configuration on a subsequent stage. The planarizing film  33  connects the color filter  32  and the oxide film  35  so as to be closely contact with each other. 
     The light-shielding film  34  including a metallic film such as tungsten (W), for example, shields the incident light to adjacent pixels, thereby preventing crosstalk of the incident light between the pixels. The oxide film  35  electrically insulates the adjacent pixels and prevents the crosstalk of the pixel signals between the adjacent pixels. 
     The intermediate first layer  37  and the intermediate second layer  36  form an intermediate layer including a two-layer pseudo high refractive layer and serve as a reflection ratio adjusting layer for suppressing reflection on the Si substrate  38 . 
     In further detail, the reflection ratio adjusting layer being a structure for suppressing the reflection of the incident light indicated by a range enclosed by a dotted line in  FIG. 1  has a configuration as illustrated in  FIG. 2 . 
       FIG. 2  is a view illustrating a configuration of the reflection ratio adjusting layer being the structure for suppressing the reflection of the incident light enclosed by the dotted line in the solid-state imaging device  11  in  FIG. 1 . In  FIG. 2 , the oxide film  35 , the intermediate second layer  36 , the intermediate first layer  37 , and the Si substrate  38  are provided in this order from above. Among them, the intermediate second layer  36  and the intermediate first layer  37  serve as the reflection ratio adjusting layer. 
     As illustrated in a left view in  FIG. 3 , the solid-state imaging device  11  is obtained by stacking the oxide film  35  having a refractive index n 0 , the intermediate second layer  36  having a refractive index n 1 , and the Si substrate  38  having a refractive index n 2 . Furthermore, a fine uneven structure is formed in the intermediate first layer  37 , and a recess portion thereof is filled with a material forming the intermediate second layer  36 . Such intermediate first layer  37  and intermediate second layer  36  form the reflection ratio adjusting layer. 
     Such a configuration is similar to a configuration in which the intermediate first layer  37  having an effective refractive index neff is formed between the Si substrate  38  having the refractive index n 2  and the intermediate second layer  36  having the refractive index n 1  as illustrated in a right view in  FIG. 3 . Hereinafter, the description is appropriately continued on the assumption that the solid-state imaging device  11  has the effective refractive index neff as illustrated in the right view in  FIG. 3 . 
     This effective refractive index neff is an effective refractive index of the reflection ratio adjusting layer having the fine uneven structure, and is a value between the refractive index n 1  of the material (intermediate second layer  36 ) embedded in the uneven structure and the refractive index n 2  of the Si substrate  38  forming the photodiode. 
     The intermediate second layer  36  includes, for example, a material having the refractive index n 1  of 1.9 to 2.3 such as Al2O3, SiN, HfO2, Ta2O5, Nb2O5, and TiO2. 
     Furthermore, for example, the intermediate first layer  37  has a configuration obtained by arranging the material forming the intermediate second layer  36  and the material Si forming the Si substrate  38  in a mixed manner. In further detail, as illustrated in  FIG. 4 , the configuration is such that the uneven structure is formed on the Si substrate  38  and a recess portion  37   a  thereof is filled with the material forming the intermediate second layer  36 . 
     Note that, in  FIG. 4 , the recess portion  37   a  is filled with the material forming the intermediate second layer  36 , so that a structure is such that this is formed into a prismatic shape and is provided in the recess portion  37   a  in the uneven structure on the Si substrate  38 . Here, the structure formed in the recess portion  37   a  is not limited to the prismatic one and this may have other shapes; this may be a cylindrical structure as described later, for example. 
     Furthermore, the intermediate first layer  37  is formed such that the effective refractive index neff of the intermediate first layer  37  becomes a predetermined value as a whole by a configuration in which the material forming the Si substrate  38  and the material forming the intermediate second layer  36  are arranged in a mixed manner with a volume ratio therebetween being a predetermined value within a range of a height H 1  of the recess portion  37   a  ( FIG. 2 ) from 40 to 70 nm, for example. 
     The material forming the Si substrate  38  and the material forming the intermediate second layer  36  are arranged in a mixed manner with the volume ratio therebetween being a predetermined value such that the effective refractive index neff is set to a value satisfying refractive index n 0 &lt;refractive index n 1 &lt;effective refractive index neff&lt;refractive index n 2 . 
     For example, in a case where a volume V 1  of the recess portion  37   a  forming the intermediate first layer  37  and a volume V 2  of a range including the same material as that of the Si substrate  38  (projected portion with respect to the recess portion  37   a ) satisfy V 1 :V 2 =3:2, when the refractive index n 2  of the material Si of the Si substrate  38  is 4.1 and the material forming the intermediate second layer  36  is Ta2O5 having the refractive index n 1  of 2.2, the intermediate first layer  37  having an averaged effective refractive index neff of about 2.7 is deposited by arrangement in a mixed manner according to the volume ratio. Specifically, the effective refractive index neff is obtained from equation (4) described later. In this case, f is V 1 /(V 1 +V 2 ) 0.6. 
     However, in a case where the refractive index n 0  of the oxide film  35  of SiO2 is 1.46 and the refractive index n 2  of the Si substrate  38  is 4.1, a substance having another refractive index may be the intermediate first layer  37  and the intermediate second layer  36  as long as refractive index n 0 &lt;refractive index n 1 &lt;effective refractive index neff&lt;refractive index n 2  is satisfied. Note that, as for the Si substrate  38 , this is similar for a substrate of InGaAs having a refractive index of about 4.0. 
     In  FIG. 2 , although the heights H 1  of the recess portions  37   a  are illustrated as the same height, in the solid-state imaging device  11  to which the present technology is applied, they are different depending on the color of the color filter  32  (wavelength of the light received by the photoelectric conversion element). 
     That is, the height H 1  of the recess portion  37   a  is set to a height suitable for condensing the light transmitted through the color filter  32  by the photoelectric conversion element (photodiode) without reflecting or diffracting the same. 
     Note that the height H 1  of the recess portion  37   a  corresponds to a thickness of the intermediate first layer with reference to  FIG. 2 . In other words, the solid-state imaging device  11  to which the present technology is applied has a structure in which this is set to the thickness of the intermediate first layer  37  optimized for the color of the color filter  32  (wavelength of the light received by the photoelectric conversion element), and the thicknesses are different for the respective pixels. 
     That is, the thickness of the intermediate first layer  37  is set to the thickness suitable for condensing the light transmitted through the color filter  32  by the photoelectric conversion element (photodiode) without reflecting or diffracting the same. 
     A reason that the heights H 1  of the recess portions  37   a  are set to be different depending on the color of the color filter  32 , specific heights thereof, and the like are described below. In the following description, since the thickness of the intermediate first layer  37 =the height H of the recess portion  37   a , this is continuously described as the height H of the recess portion  37   a , but this may be replaced with the thickness of the intermediate first layer  37 . 
     &lt;Condition Under which No Diffraction Light is Generated&gt; 
     The intermediate first layer  37  and the intermediate second layer  36  are formed to have the fine uneven structure and serve as the reflection ratio adjusting layer; a condition under which the diffraction light is not generated by this reflection ratio adjusting layer (uneven structure) is described with reference to  FIG. 5 . A case where light having a wavelength λ 0  in vacuum is incident at an incident angle i 1  on the uneven structure with a pitch P as illustrated in  FIG. 5  is considered. 
     The pitch P is a value obtained by adding a width of one recess portion and one projected portion of the uneven structure, and a value obtained by adding a width W 1  ( FIG. 2 ) of the recess portion  37   a  of the intermediate first layer  37  and a width W 2  ( FIG. 2 ) of the projected portion  37   b  of the intermediate first layer  37 , for example. 
     The refractive index above the uneven structure is set to n 1  and that below the same is set to n 2 . For example, in  FIG. 2 , the intermediate second layer  36  with the refractive index n 1  is present above and the Si substrate  38  with the refractive index n 2  is present below. A condition of the pitch P at which the diffraction light is not generated on a reflection side of the uneven structure, that is, on the side of the intermediate second layer  36  is given by following equation (1). 
     
       
         
           
             
               
                 
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     Furthermore, a condition of the pitch P at which the diffraction light is not generated on a transmission side of the uneven structure, that is, on the side of the Si substrate  38  is given by following equation (2). In equation (2), i 2  represents the light incident on the Si substrate  38  at the incident angle i 1 , 
     
       
         
           
             
               
                 
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     A graph when simulating the pitch P satisfying such condition by using ALSO3 as the material above (the material of the intermediate second layer  36  of the refractive index n 1 ) and Si as the material below (the material of the Si substrate  38  with the refractive index n 2 ) is illustrated in  FIG. 6 . 
     In the graph illustrated in  FIG. 6 , the wavelength of the incident light is plotted along the abscissa and the pitch P is plotted along the ordinate. A wavelength region in vacuum is often used by the solid-state imaging device which senses visible light, so that a case of 400 to 700 nm is illustrated in  FIG. 6 . Furthermore, in  FIG. 6 , lozenges represent values calculated by equation (1) and a straight line connecting the values is a straight line  1 . Furthermore, in  FIG. 6 , squares represent values calculated by equation (2) and a value connecting the straight lines is a straight line  2 . 
     The pitch P satisfying equations (1) and (2) described above is in an area below the straight line  1  and below the straight line  2  in  FIG. 6 . For example, for the wavelength of 400 nm in vacuum, no diffraction light is generated at the pitch P smaller than 55 nm. 
     In the solid-state imaging device  11 , since a component of the light incident on the photodiode in an oblique direction is not large, it is considered that an effect is sufficiently obtained even if the incident angle is 30 degrees or smaller, and it is considered that the effect is obtained only with 0 degree incidence. This is described with reference to  FIG. 7 . 
       FIG. 7  is a graph illustrating a result of simulating the pitch P at which no diffraction light is generated as in the graph illustrated in  FIG. 6 , in which the wavelength of the incident light is plotted along the abscissa and a width of the pitch P is plotted along the ordinate with the material above being ALSO3 and the material below being Si. 
     In  FIG. 7 , lozenges represent an upper limit when the incident angle is 0 degree, and squares represent a lower limit when the incident angle is 0 degree. Furthermore, in  FIG. 7 , triangles represent an upper limit when the incident angle is 30 degree, and cross marks represent a lower limit when the incident angle is 30 degree. 
     It may be understood from  FIG. 7  that it is necessary to form the uneven structure with the pitch of 70 nm or smaller in order to prevent the diffraction light from being generated on an emission side also for perpendicular incidence. 
     With a moth-eye structure film an upper surface of which is air, it is sufficient that the pitch P is 200 to 300 nm, and such pitch P may be easily manufactured. However, it is difficult to form an uneven pattern with the pitch P of 70 nm or smaller on the photodiode by the conventional technology from a viewpoint of size and material to be processed. 
     &lt;Regarding Formation of Uneven Pattern at Pitch P&gt; 
     By applying the present technology, it is possible to form the uneven pattern having the pitch P of 70 nm or smaller, preferably 55 nm or smaller. Hereinafter, a method of forming such pitch P is described. 
       FIG. 8  is a view illustrating an example of a shape of the uneven pattern.  FIG. 8  is a view illustrating the uneven pattern when the solid-state imaging device  11  is seen from an upper surface (lens  31  side). A circle illustrated in  FIG. 8  indicates the projected portion  37   b  formed in the intermediate first layer  37 , and a portion between the projected portions  37   b  indicates the recess portion  37   a . Here, the description is continued on the assumption that the projected portion  37   b  formed in the intermediate first layer  37  is circular (cylindrical). 
     In order to spread the uneven pattern at a small pitch P, an upper surface layout as illustrated in A of  FIG. 8  or B of  FIG. 8  is used in many cases. A of  FIG. 8  illustrates an example in which the projected portions  37   b  being cylinders are arranged in a hexagonal lattice. Furthermore, B of  FIG. 8  illustrates an example in which the projected portions  37   b  being cylinders are arranged in a square lattice. An interval between the projected portions  37   b  being cylinders is set as the pitch P. 
     Incidentally, a semiconductor process is often used to manufacture the solid-state imaging device  11 . For pattern formation, a lithography technology, especially an optical lithography technology is often used. A reduction projection exposure device is used to form a fine pattern. With a numerical aperture of a reduction projection lens thereof set to NA and a maximum value of an expected angle of illumination set to θ, when light diffracted by a mask pattern enters the projection lens. light and dark of the pattern appear. 
     A pitch Pmin at which the light diffracted by the pattern of the mask enters the projection lens is given by following equation (3). In equation (3), λ represents an exposure wavelength. A refractive index of a medium under the projection lens is set to n and the expected angle of the projection lens as seen from a focal point is set to φ. 
     
       
         
           
             
               
                 
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     Consider forming the pitch Pmin satisfying such a condition. In an ArF excimer laser exposure device having the exposure wavelength of 193 nm which is often used for fine pattern formation, when the numerical aperture NA of the lens is set to 0.93 and σ is set to 0.94, for example, a diffraction limit pitch is 107 nm. 
     For resolution of resist with a two-dimensional array pattern as illustrated in  FIG. 8 , it is expected that √2 times or more thereof is required. Therefore, a resolution limit pitch Pmin at that time is 151 nm. 
     In a case of the hexagonal lattice illustrated in A of  FIG. 8  with the pitch P of 70 nm, it is difficult to form by one exposure and one etching, and it is considered to be necessary to repeat the exposure and the etching at least three times. In addition, considering manufacturing stability, it is considered to be necessary to repeat the same nine times. 
     Furthermore, in a case of the hexagonal lattice illustrated in A of  FIG. 8  with the pitch P of 55 nm or smaller, it is necessary to repeat the exposure and etching at least nine times, and considering the manufacturing stability, it is necessary to further repeat the same a plurality of times. In such manufacture, a cost might be high. 
     Similarly, in a case of the square lattice illustrated in B of  FIG. 8  with the pitch P of 70 nm, it is difficult to form by one exposure and one etching using the ArF excimer laser exposure device, and it is considered to be necessary to repeat the exposure and etching at least four times. In addition, considering the manufacturing stability, it is considered to be necessary to further repeat the same a plurality of times. 
     Furthermore, in a case of the square lattice illustrated in B of  FIG. 8  with the pitch P of 55 nm or smaller, it is necessary to repeat the exposure and etching at least four times, and considering the manufacturing stability, it is necessary to repeat the same eight times. In such manufacture, manufacturing steps might be complicated and the cost might be increased. 
     In other words, in a case of forming the uneven pattern with the pitch P of 70 nm or smaller by the hexagonal lattice illustrated in A of  FIG. 8  or the square lattice illustrated in B of  FIG. 8  by the ArF excimer laser exposure device having the exposure wavelength of 193 nm which is widely used for fine pattern formation, there is a possibility that the number of times of repeating the exposure and etching increases and the manufacturing cost increases. 
     A case where an immersion ArF excimer laser exposure device capable of forming a finer pattern than the ArF excimer laser exposure device is used is considered though the cost is generally higher than that of the above-described ArF excimer laser exposure device. 
     As with the ArF excimer laser exposure device described above, the exposure wavelength of the immersion ArF excimer laser exposure device is 193 nm. When NA is 1.35 and σ is 0.94, the diffraction limit pitch is 74 nm. For the resolution of the resist with the two-dimensional array pattern as illustrated in  FIG. 8 , it is expected that √2 times or more thereof is required. Then, the resolution limit pitch is 104 nm. 
     In a case of the hexagonal lattice illustrated in A of  FIG. 8  with the pitch P of 70 nm, it is difficult to form by one exposure and one etching even with the immersion ArF excimer laser exposure device. Furthermore, considering the manufacturing stability, it is considered to be necessary to repeat exposure and etching three times. 
     In a case of the hexagonal lattice illustrated in A of  FIG. 8  with the pitch P of 55 nm or smaller, it is necessary to repeat the exposure and etching at least three times. Furthermore, considering the manufacturing stability, it is considered to be necessary to further repeat the exposure and etching a plurality of times. In such manufacture, manufacturing steps might be complicated and the cost might be increased. 
     In a case of the square lattice illustrated in B of  FIG. 8  with the pitch P of 70 nm, it is difficult to form by one exposure and one etching even with the immersion ArF excimer laser exposure device. Furthermore, considering the manufacturing stability, it is considered to be necessary to repeat the exposure and etching twice, more preferably, four times. 
     In a case of the square lattice illustrated in B of  FIG. 8  with the pitch P of 55 nm or smaller, it is necessary to repeat the exposure and etching at least twice. Furthermore, considering the manufacturing stability, it is considered to be necessary to repeat the exposure and etching four times. In such manufacture, manufacturing steps might be complicated and the cost might be increased. 
     Moreover, there is an EUV exposure device as means for forming the fine pattern. The EUV exposure device with the exposure wavelength of 13.5 nm, NA of 0.35, and σ of 0.8 may form a pitch of 30 nm or smaller. The EUV exposure device may form a pattern with a pitch of 55 nm or smaller by one exposure. However, since the exposure device is very expensive, the cost is increased as with the above-described device. 
     Moreover, there is an electron beam drawing device as means for forming the fine pattern. As with the EUV exposure device, the electron beam drawing device may form a pattern with a pitch P of 55 nm or smaller by one exposure. However, since a throughput is low, more devices are required for mass production, and the cost might finally increase. 
     Moreover, there is a method of utilizing self assembly as means for forming the fine pattern. In other words, when forming the uneven structure, the optical lithography may be used as described above; however, for example, it is also possible to configure such that the volume of Si which is the material of the Si substrate  38  and the volume of the recess portion  37   a  have the above-described volume ratio by using a self assembly, and form the recess portion  37   a  by etching. 
     For example, in a case of using the self assembly, polymers such as block copolymers and metal nanoparticles may form periodic patterns through interaction. 
     For example, using block copolymer PS-b-PMMA including polystyrene (PS) and polymethyl methacrylate (PMMA), it is possible to form a hole array pattern with the pitch P of 30 nm to 70 nm. The pitch P is determined by a molecular weight of PS-b-PMMA. After a neutral film for adjusting surface energy is formed on a wafer substrate by spin-coating and baking, PS-b-PMMA is spin-coated, and phase separation baking is applied to promote the self assembly. 
     By such a step, a hole array is formed by dry etching or wet etching PMMA out of periodically arrayed PS-b-PMMA. A grain boundary is generated in the process of phase separation, but the hole array may be formed without exposure. This is an advantage that the cost may be lowered. 
     Moreover, as another means for forming the fine pattern, there is a nano imprinting method. The nano imprinting method is a method of pressing a template having resin solution and a pattern on a wafer to print. The resin solution is solidified by UV irradiation or heating. The printing is repeatedly performed on the entire wafer surface or divided areas. 
     In terms of requiring the template having the fine pattern and a nano imprinting device, there is a possibility that the cost becomes higher than that in the self assembly described above. However, unlike the self assembly, there is an advantage that the size may be changed for each pattern. 
     The nano imprinting method is also a candidate for pattern formation. Note that, although an imprinting method is partially used for forming moth-eye for display, the nano imprinting method capable of forming a finer pattern is suitable for this purpose. 
     Unlike forming a circuit, high positional accuracy and dimensional accuracy are not required for forming a periodic pattern for an antireflective structure. From this viewpoint also, the self assembly and the nano imprinting method are suitable as means for forming the fine pattern. 
     In this manner, there are the ArF excimer laser exposure device, the immersion ArF excimer laser exposure device, the EUV exposure device, and the electron beam drawing device as means for forming the fine pattern, but there is a possibility that the step becomes complicated and the cost becomes high. Therefore, it is possible to form the fine uneven pattern satisfying the condition of the pitch P described above by using the ArF excimer laser exposure device, the immersion ArF excimer laser exposure device, the EUV exposure device, the electron beam drawing device and the like such as in a case where the cost may be high. 
     Furthermore, in a case where it is possible to prevent a complicated step and a high cost and the fine uneven pattern satisfying the above-described condition of the pitch P is formed, it is possible to form by using the self assembly and the nano imprinting method. 
     Hereinafter, a case of forming the fine uneven pattern is further described. 
     &lt;Regarding Effective Refractive Index with which Diffraction Light is not Generated&gt; 
     Next, the effective refractive index (effective refractive index neff of the intermediate first layer  37  described with reference to  FIG. 3 ) of the uneven pattern with which the diffraction light is not generated is described. 
     As described with reference to  FIG. 3 , an uneven area of the intermediate first layer  37  may be optically handled as a planar surface film of an intermediate effective refractive index neff between the refractive index n 1  of a medium  1  above and the refractive index n 2  of a medium  2  below (refractive index n 1  of the intermediate second layer  36  and refractive index n 2  of the Si substrate  38 ). Specifically, the effective refractive index neff is given by following Lorentz-Lorenz equation (4). In this regard, space occupancy of the medium  1  is set to f. 
     
       
         
           
             
               
                 
                   [ 
                   
                     Equation 
                     ⁢ 
                     
                         
                     
                     ⁢ 
                     4 
                   
                   ] 
                 
               
               
                 
                     
                 
               
             
             
               
                 
                   
                     
                       
                         n 
                         eff 
                         2 
                       
                       - 
                       1 
                     
                     
                       
                         n 
                         eff 
                         2 
                       
                       + 
                       2 
                     
                   
                   = 
                   
                     
                       f 
                       ⁢ 
                       
                         
                           
                             n 
                             1 
                             2 
                           
                           - 
                           1 
                         
                         
                           
                             n 
                             1 
                             2 
                           
                           + 
                           2 
                         
                       
                     
                     + 
                     
                       
                         ( 
                         
                           1 
                           - 
                           f 
                         
                         ) 
                       
                       ⁢ 
                       
                         
                           
                             n 
                             2 
                             2 
                           
                           - 
                           1 
                         
                         
                           
                             n 
                             2 
                             2 
                           
                           + 
                           2 
                         
                       
                     
                   
                 
               
               
                 
                   ( 
                   4 
                   ) 
                 
               
             
           
         
       
     
     Next, an antireflective condition is described. Since components nearly perpendicular are dominant in the light incident on the photodiode of the solid-state imaging device  11 , the description is herein continued taking a case of perpendicular incidence as an example. 
     As illustrated in  FIG. 9 , an amplitude reflection ratio at an interface between the medium  1  and the intermediate layer is set to r 1 , an amplitude reflection ratio at an interface between the medium  2  and the intermediate layer is set to r 2 , and the height (thickness) of the intermediate layer is set to H. The medium  1  in  FIG. 9  corresponds to the intermediate second layer  36  having the refractive index n 1  in  FIG. 3 , for example. Furthermore, the medium  2  in  FIG. 9  corresponds to the Si substrate  38  having the refractive index n 2  in  FIG. 3 , for example. Furthermore, the intermediate layer in  FIG. 9  corresponds to the intermediate first layer  37  having the effective refractive index neff in  FIG. 3 , for example. 
     In  FIG. 9 , the light interferes in a multiple manner in the intermediate layer, and an intensity reflection ratio R on an upper surface of the intermediate layer is given by following equation (5). 
     
       
         
           
             
               
                 
                   [ 
                   
                     Equation 
                     ⁢ 
                     
                         
                     
                     ⁢ 
                     5 
                   
                   ] 
                 
               
               
                 
                     
                 
               
             
             
               
                 
                   
                     R 
                     = 
                     
                       
                         
                           r 
                           1 
                           2 
                         
                         + 
                         
                           r 
                           2 
                           2 
                         
                         + 
                         
                           2 
                           ⁢ 
                           
                             r 
                             1 
                           
                           ⁢ 
                           
                             r 
                             2 
                           
                           ⁢ 
                           
                               
                           
                           ⁢ 
                           cos 
                           ⁢ 
                           
                               
                           
                           ⁢ 
                           ϕ 
                         
                       
                       
                         1 
                         + 
                         
                           
                             ( 
                             
                               
                                 r 
                                 1 
                               
                               ⁢ 
                               
                                 r 
                                 2 
                               
                             
                             ) 
                           
                           2 
                         
                         + 
                         
                           2 
                           ⁢ 
                           
                             r 
                             1 
                           
                           ⁢ 
                           
                             r 
                             2 
                           
                           ⁢ 
                           cos 
                           ⁢ 
                           
                               
                           
                           ⁢ 
                           ϕ 
                         
                       
                     
                   
                   ⁢ 
                   
                     
 
                   
                   ⁢ 
                   
                     
                       
                         r 
                         1 
                       
                       = 
                       
                         
                           
                             n 
                             eff 
                           
                           - 
                           
                             n 
                             1 
                           
                         
                         
                           
                             n 
                             eff 
                           
                           + 
                           
                             n 
                             1 
                           
                         
                       
                     
                     , 
                     
                       
                         r 
                         2 
                       
                       = 
                       
                         
                           
                             n 
                             2 
                           
                           - 
                           
                             n 
                             eff 
                           
                         
                         
                           
                             n 
                             2 
                           
                           + 
                           
                             n 
                             eff 
                           
                         
                       
                     
                     , 
                     
                       ϕ 
                       = 
                       
                         
                           4 
                           ⁢ 
                           π 
                           ⁢ 
                           
                               
                           
                           ⁢ 
                           
                             n 
                             eff 
                           
                           ⁢ 
                           H 
                         
                         
                           λ 
                           0 
                         
                       
                     
                   
                 
               
               
                 
                   ( 
                   5 
                   ) 
                 
               
             
           
         
       
     
     A condition under which the intensity reflection ratio on the upper surface of the intermediate layer is minimized is as follows. Following equation (6) expresses a condition of the effective refractive index neff with which the intensity reflection ratio on the upper surface of the intermediate layer is minimized, and following equation (7) expresses a condition of the height H 1  ( FIG. 2 ) of the projected portion  37   b  with which the intensity reflection ratio on the upper surface of the intermediate layer is minimized. In this regard, the refractive index is a function of the wavelength. 
     
       
         
           
             
               
                 
                   [ 
                   
                     Equation 
                     ⁢ 
                     
                         
                     
                     ⁢ 
                     6 
                   
                   ] 
                 
               
               
                 
                     
                 
               
             
             
               
                 
                   
                     n 
                     eff 
                   
                   = 
                   
                     
                       
                         n 
                         1 
                       
                       ⁢ 
                       
                         n 
                         2 
                       
                     
                   
                 
               
               
                 
                   ( 
                   6 
                   ) 
                 
               
             
             
               
                 
                   [ 
                   
                     Equation 
                     ⁢ 
                     
                         
                     
                     ⁢ 
                     7 
                   
                   ] 
                 
               
               
                 
                     
                 
               
             
             
               
                 
                   H 
                   = 
                   
                     
                       
                         λ 
                         0 
                       
                       
                         4 
                         ⁢ 
                         
                           n 
                           eff 
                         
                       
                     
                     = 
                     
                       
                         λ 
                         0 
                       
                       
                         4 
                         ⁢ 
                         
                           
                             
                               n 
                               1 
                             
                             ⁢ 
                             
                               n 
                               2 
                             
                           
                         
                       
                     
                   
                 
               
               
                 
                   ( 
                   7 
                   ) 
                 
               
             
           
         
       
     
     For example, in a case where the medium  1  is Al2O3 and the medium  2  is Si, the effective refractive index neff and the height H of the antireflective condition of the intermediate layer are as illustrated in  FIGS. 10 and 11 .  FIG. 10  is a graph in which a calculation result based on equation (6) is plotted when the wavelength of the light is along the abscissa and the effective refractive index neff is along the ordinate. Furthermore,  FIG. 11  is a graph in which a calculation result based on equation (7) is plotted when the wavelength of the light along the abscissa and the height H of the projected portion  37   b  is along the ordinate. 
     It may be understood from  FIG. 10  that the uneven structure may realize a relatively high effective refractive index neff from 2.4 to 3.1. Furthermore, it may be understood from  FIGS. 10 and 11  that the effective refractive index neff and the height H of the intermediate layer are dependent on the wavelength, and the effective refractive index neff and the height H of the intermediate layer are ideally optimized for each wavelength. 
     From equation (7), it may be understood that it is sufficient that the height H is an integral multiple of λ 0 /4 neff. Furthermore, it may be understood that the height H depends on the wavelength λ 0 . With this arrangement, it is conceivable that the height. H is set to λ 0 /4 neff which is a first optimal solution with small difference. Furthermore, in a case where H is set to λ 0 /4 neff, grooves of unevenness become shallow, so that processing is considered to be easier. 
     For example, a result of simulating the intensity of the reflection light on the upper surface of the intermediate layer by a FDTD method being one type of electromagnetic field calculation while changing a depth of the cylinder in a case where the hexagonal lattice Si cylindrical holes (with pitch of 40 nm and diameter of 30 nm) are formed on the Si substrate  38 , the intermediate film (intermediate first layer  37 ) having the refractive index of 1.7 is stacked thereon, and the SiO2 film (oxide film  35 ) is further formed thereon as illustrated in  FIG. 12  is illustrated in  FIG. 13 . 
     In a graph illustrated in  FIG. 13 , the height H of the projected portion  37   b  (the depth of the recess portion  37   a , the thickness of the intermediate first layer  37 ) is plotted along the abscissa, and the reflection intensity is plotted along the ordinate. Furthermore, in  FIG. 13 , a line connecting lozenges represents a result of the simulation when the wavelength of the incident light is 450 nm, a line connecting squares represents a result of the simulation when the wavelength of the incident light is 530 nm, and a line connecting triangles represents a result of the simulation when the wavelength of the incident light is 620 nm. Note that each wavelength is a wavelength in vacuum. 
     It may be understood from the graph in  FIG. 13  that the reflection intensity oscillates with respect to the depth of the cylindrical hole (the height H of the projected portion  37   b ). It may also be understood from the graph in  FIG. 13  that a period of the oscillation is proportional to the wavelength. 
     With this arrangement, it may be understood that the depth of the cylindrical hole at which the reflection intensity is minimum depends on the wavelength. Furthermore, it may also be understood that setting the depth (height H) of the cylindrical hole in the vicinity of a first point at which the reflection ratio decreases is desirable from the viewpoint of reducing the reflection ratio over a wide wavelength region. 
     Here, the relationship among the effective refractive index neff, the refractive index n 1 , and the refractive index n 2  is considered again. The relationship among the effective refractive index neff, the refractive index n 1 , and the refractive index n 2  may be represented by equation (4) described above. From this equation (4), when the effective refractive index neff of the antireflective condition is determined, optimum space occupancy f realizing the effective refractive index neff may also be calculated as follows. 
     
       
         
           
             
               
                 
                   [ 
                   
                     Equation 
                     ⁢ 
                     
                         
                     
                     ⁢ 
                     8 
                   
                   ] 
                 
               
               
                 
                     
                 
               
             
             
               
                 
                   f 
                   = 
                   
                     
                       
                         A 
                         2 
                       
                       - 
                       
                         A 
                         eff 
                       
                     
                     
                       
                         A 
                         2 
                       
                       - 
                       
                         A 
                         1 
                       
                     
                   
                 
               
               
                 
                   ( 
                   8 
                   ) 
                 
               
             
           
         
       
     
     In equation (8), Aeff, A 1 , and A 2  satisfy following equation (9), respectively. 
     
       
         
           
             
               
                 
                   [ 
                   
                     Equation 
                     ⁢ 
                     
                         
                     
                     ⁢ 
                     9 
                   
                   ] 
                 
               
               
                 
                     
                 
               
             
             
               
                 
                   
                     
                       A 
                       eff 
                     
                     = 
                     
                       
                         
                           
                             n 
                             eff 
                             2 
                           
                           - 
                           1 
                         
                         
                           
                             n 
                             eff 
                             2 
                           
                           + 
                           2 
                         
                       
                       = 
                       
                         
                           
                             
                               n 
                               1 
                             
                             ⁢ 
                             
                               n 
                               2 
                             
                           
                           - 
                           1 
                         
                         
                           
                             
                               n 
                               1 
                             
                             ⁢ 
                             
                               n 
                               2 
                             
                           
                           + 
                           2 
                         
                       
                     
                   
                   , 
                   
                     
                       A 
                       1 
                     
                     = 
                     
                       
                         
                           n 
                           1 
                           2 
                         
                         - 
                         1 
                       
                       
                         
                           n 
                           1 
                           2 
                         
                         + 
                         2 
                       
                     
                   
                   , 
                   
                     
                       A 
                       2 
                     
                     = 
                     
                       
                         
                           n 
                           2 
                           2 
                         
                         - 
                         1 
                       
                       
                         
                           n 
                           2 
                           2 
                         
                         + 
                         2 
                       
                     
                   
                 
               
               
                 
                   ( 
                   9 
                   ) 
                 
               
             
           
         
       
     
     The optimum space occupancy f also depends on the wavelength as the effective refractive index neff of the antireflective condition depends on the wavelength. Therefore, when this is reflected in equation (8), this may be expressed as following equation (10). 
     
       
         
           
             
               
                 
                   [ 
                   
                     Equation 
                     ⁢ 
                     
                         
                     
                     ⁢ 
                     10 
                   
                   ] 
                 
               
               
                 
                     
                 
               
             
             
               
                 
                   
                     f 
                     ⁡ 
                     
                       ( 
                       λ 
                       ) 
                     
                   
                   = 
                   
                     
                       
                         
                           
                             A 
                             2 
                           
                           ⁡ 
                           
                             ( 
                             λ 
                             ) 
                           
                         
                         - 
                         
                           
                             A 
                             eff 
                           
                           ⁡ 
                           
                             ( 
                             λ 
                             ) 
                           
                         
                       
                       
                         
                           
                             A 
                             2 
                           
                           ⁡ 
                           
                             ( 
                             λ 
                             ) 
                           
                         
                         - 
                         
                           
                             A 
                             1 
                           
                           ⁡ 
                           
                             ( 
                             λ 
                             ) 
                           
                         
                       
                     
                     ≡ 
                     
                       F 
                       ⁡ 
                       
                         ( 
                         λ 
                         ) 
                       
                     
                   
                 
               
               
                 
                   ( 
                   10 
                   ) 
                 
               
             
           
         
       
     
     For example, in a case where the medium  1  is Al2O3 and the medium  2  is Si, the dependency of the optimum space occupancy f on the wavelength λ is as illustrated in  FIG. 14 . In a graph illustrated in  FIG. 14 , the wavelength λ 0  is plotted along the abscissa and the space occupancy f is plotted along the ordinate. 
     From the graph in  FIG. 14 , it may be understood that in a case where the wavelength λ 0  is 400 to 700 nm, the optimum space occupancy f transits between about 0.3 to 0.4. 
     Incidentally, in a case of a pixel array (pixel array unit) which discriminates colors in a planar direction, it is desirable to optimize the antireflective condition for each color. Each pixel has, for example, a spectral characteristic as illustrated in  FIG. 15 , and the wavelength continuously exists in each pixel. In  FIG. 15 , the wavelength is plotted along the abscissa, quantum efficiency is plotted along the abscissa, a solid line represents red (R), a broken line represents green (G), and a dashed-dotted line represents blue (B). 
     As described above, it may be understood from a graph in  FIG. 15  that red, green, and blue have different spectral characteristics. Therefore, optimum values of the thickness of the intermediate first layer  37  (the height of the projected portion  37   b ), the space occupancy, the pitch and the like are different for each color, and it is considered to be preferably configured with the optimum values for each color (each pixel). A method of further suppressing the reflection ratio is described. 
     &lt;Regarding Determination of Space Occupancy f&gt; 
     First, a method of determining the space occupancy f of the medium  1  (intermediate second layer  36 ) directly related to the effective refractive index of the intermediate layer (the effective refractive index neff of the intermediate first layer  37 ) is described. Since the intermediate first layer  37  is obtained by filling the recess portion  37   a  of the Si substrate  38  with the same material as that of the intermediate second layer  36 , the space occupancy f of the intermediate second layer  36  relates to the effective refractive index neff of the intermediate first layer  37 . 
     As determining methods A-1 to A-4, a case of making the effective refractive index neff common to all pixels is described, and as determining methods B-1 to B-3, a case of adjusting the effective refractive index neff for each pixel is described. 
     The determining methods A-1 to A-4 are conditions applied in a case of making the effective refractive index neff common to all the pixels, for example, in a case where it is difficult to adjust the size (the pitch P, the diameter of the cylindrical hole and the like) of the uneven pattern for each pixel by using the self assembly. In the following description, description is continued on the assumption that the wavelength region (the wavelength region of light received and processed by the solid-state imaging device  11 ) which the solid-state imaging device  11  may discriminate is λmin to λmax. 
     (Determining Method A-1) 
     An average value is used, and a value obtained by following equation (11) is set to the space occupancy f of the medium  1  (intermediate second layer  36 ). 
     
       
         
           
             
               
                 
                   [ 
                   
                     Equation 
                     ⁢ 
                     
                         
                     
                     ⁢ 
                     11 
                   
                   ] 
                 
               
               
                 
                     
                 
               
             
             
               
                 
                   f 
                   = 
                   
                     
                       
                         ∫ 
                         
                           λ 
                           min 
                         
                         
                           λ 
                           max 
                         
                       
                       ⁢ 
                       
                         
                           F 
                           ⁡ 
                           
                             ( 
                             λ 
                             ) 
                           
                         
                         ⁢ 
                         d 
                         ⁢ 
                         
                             
                         
                         ⁢ 
                         λ 
                       
                     
                     
                       
                         λ 
                         max 
                       
                       - 
                       
                         λ 
                         min 
                       
                     
                   
                 
               
               
                 
                   ( 
                   11 
                   ) 
                 
               
             
           
         
       
     
     In equation (11), F(λ) represents a value calculated by equation (10). 
     (Determining Method A-2) 
     An average value weighted by spectral sensitivity W(λ) is used, and a value obtained by following equation (12) is set to the space occupancy f of the medium  1  (intermediate second layer  36 ). 
     
       
         
           
             
               
                 
                   [ 
                   
                     Equation 
                     ⁢ 
                     
                         
                     
                     ⁢ 
                     12 
                   
                   ] 
                 
               
               
                 
                     
                 
               
             
             
               
                 
                   f 
                   = 
                   
                     
                       
                         ∫ 
                         
                           λ 
                           min 
                         
                         
                           λ 
                           max 
                         
                       
                       ⁢ 
                       
                         
                           w 
                           ⁡ 
                           
                             ( 
                             λ 
                             ) 
                           
                         
                         ⁢ 
                         
                           F 
                           ⁡ 
                           
                             ( 
                             λ 
                             ) 
                           
                         
                         ⁢ 
                         d 
                         ⁢ 
                         
                             
                         
                         ⁢ 
                         λ 
                       
                     
                     
                       
                         ∫ 
                         
                           λ 
                           min 
                         
                         
                           λ 
                           max 
                         
                       
                       ⁢ 
                       
                         
                           w 
                           ⁡ 
                           
                             ( 
                             λ 
                             ) 
                           
                         
                         ⁢ 
                         d 
                         ⁢ 
                         
                             
                         
                         ⁢ 
                         λ 
                       
                     
                   
                 
               
               
                 
                   ( 
                   12 
                   ) 
                 
               
             
           
         
       
     
     (Determining Method A-3) 
     It is optimized for a critical wavelength λc in image quality, and a value obtained by following equation (13) is set to the space occupancy f of the medium  1  (intermediate second layer  36 ).
 
[Equation 13]
 
 f=F (λ C )  (13)
 
     (Determining Method A-4) 
     An arbitrary value between the minimum value λmin and the maximum value λmax of the wavelength region is used, and a value obtained by following equation (14) is set to the space occupancy f of the medium  1  (intermediate second layer  36 ).
 
[Equation 14]
 
Min[ F (λ)]≤ f ≤Max[ F (λ)]  (14)
 
where
 
λ min ≤λ≤λ max  
 
     The determining methods B-1 to B-3 are conditions applied in a case of adjusting the effective refractive index neff for each pixel, for example, in a case where the size (the pitch P, the diameter of the cylindrical hole and the like) of the uneven pattern is adjusted for each pixel by using the nano imprinting method. In the following description, a red (R) pixel, a green (G) pixel, and a blue (B) pixel are described as an example. 
     (Determining Method B-1) 
     For each of the R pixel, G pixel, and B pixel, an average value weighted by the spectral sensitivity W(λ) is used, and a value obtained by following equation (15) is set to the space occupancy f of the medium  1  (intermediate second layer  36 ). 
     
       
         
           
             
               
                 
                   [ 
                   
                     Equation 
                     ⁢ 
                     
                         
                     
                     ⁢ 
                     15 
                   
                   ] 
                 
               
               
                 
                     
                 
               
             
             
               
                 
                   f 
                   = 
                   
                     
                       
                         ∫ 
                         
                           λ 
                           min 
                         
                         
                           λ 
                           max 
                         
                       
                       ⁢ 
                       
                         
                           w 
                           ⁡ 
                           
                             ( 
                             λ 
                             ) 
                           
                         
                         ⁢ 
                         
                           F 
                           ⁡ 
                           
                             ( 
                             λ 
                             ) 
                           
                         
                         ⁢ 
                         d 
                         ⁢ 
                         
                             
                         
                         ⁢ 
                         λ 
                       
                     
                     
                       
                         ∫ 
                         
                           λ 
                           min 
                         
                         
                           λ 
                           max 
                         
                       
                       ⁢ 
                       
                         
                           w 
                           ⁡ 
                           
                             ( 
                             λ 
                             ) 
                           
                         
                         ⁢ 
                         d 
                         ⁢ 
                         
                             
                         
                         ⁢ 
                         λ 
                       
                     
                   
                 
               
               
                 
                   ( 
                   15 
                   ) 
                 
               
             
           
         
       
     
     In equation (15), F(λ) represents a value calculated by equation (10). Furthermore, F(λ) is a value calculated from the effective refractive index neff of the intermediate first layer  37 , the refractive index n 1  of the intermediate second layer, and the refractive index n 2  of the Si substrate  38 , and a value indicating the space occupancy at a predetermined wavelength λ. 
     (Determining Method B-2) 
     For each of the R pixel, G pixel, and B pixel, it is optimized for the peak value λp of the spectral sensitivity W(λ), and a value obtained by following equation (16) is set to the space occupancy f of the medium  1  (intermediate second layer  36 ).
 
[Equation 16]
 
 f=F (λ p )  (16)
 
     (Determining Method B-3) 
     For each of the R pixel, G pixel, and B pixel, a threshold of the spectral sensitivity W(λ) is specified, and a value obtained by following equation (17) is set to the space occupancy f of the medium  1  (intermediate second layer  36 ). In Equation (17), a smaller value of the thresholds is set to XL, and a larger value is set to λU.
 
[Equation 17]
 
 F (λ L )≤ f≤F (λ 11 )  (17)
 
     The space occupancy f is set by any one of the determining methods A-1 to A-4 and B-1 to B-3. Here, an example of a pattern dimension of the space occupancy f is illustrated, and the space occupancy f of the medium  1  (intermediate second layer  36 ) is further described. 
       FIG. 16  is a view of the uneven pattern as seen from above. In the example illustrated in  FIG. 16 , the projected portion  37   b  has a circular shape, and a diameter thereof is set to a diameter D. Furthermore, the adjacent projected portions  37   b  are arranged at an interval of the pitch P. 
     A relationship among the space occupancy f of the medium  1 , the pitch P, and the diameter D may be expressed by following equation (18). 
     
       
         
           
             
               
                 
                   [ 
                   
                     Equation 
                     ⁢ 
                     
                         
                     
                     ⁢ 
                     18 
                   
                   ] 
                 
               
               
                 
                     
                 
               
             
             
               
                 
                   f 
                   = 
                   
                     
                       π 
                       
                         2 
                         ⁢ 
                         
                           3 
                         
                       
                     
                     ⁢ 
                     
                       
                         ( 
                         
                           D 
                           P 
                         
                         ) 
                       
                       2 
                     
                   
                 
               
               
                 
                   ( 
                   18 
                   ) 
                 
               
             
           
         
       
     
     Using equation (18), it is possible to determine the pitch P and the diameter D at which the desired space occupancy f is realized. Note that, since the space occupancy f is important, the pattern need not be a perpendicular shape, for example, a cylinder. 
     Furthermore, the space occupancy f is a statistical value (average value) within one pixel. Therefore, even if there are variations in individual patterns and sizes, it suffices that the average value is close to a desired value. For example, as illustrated in  FIG. 17 , when the hole array is formed by the self assembly, even if there is a grain boundary, a defect, and dimensional variation within one pixel, it suffices that the average value of the space occupancy f is close to a desired value within one pixel. 
     When standard deviation of the diameter D of each hole is σD and the number of holes in one pixel is n, the average value of the diameter D in the pixel and the standard deviation σ&lt;D&gt; between the pixels are expressed by following equation (19). 
     
       
         
           
             
               
                 
                   [ 
                   
                     Equation 
                     ⁢ 
                     
                         
                     
                     ⁢ 
                     19 
                   
                   ] 
                 
               
               
                 
                     
                 
               
             
             
               
                 
                   
                     σ 
                     
                       〈 
                       D 
                       〉 
                     
                   
                   = 
                   
                     
                       σ 
                       D 
                     
                     
                       n 
                     
                   
                 
               
               
                 
                   ( 
                   19 
                   ) 
                 
               
             
           
         
       
     
     For example, in a case of a pixel of 1 μm×1 μm and the pitch P of 40 nm, the number of holes n is about 720, and √n is about 27. The variation in pixel units is reduced to about 1/27 of individual variation. 
     &lt;Regarding Determination of Height H&gt; 
     Next, a method of determining the height H of the uneven pattern after setting the space occupancy f of the medium  1  of the uneven pattern is described. 
     Here, a case of determining the height H for each of the R pixel, G pixel, and B pixel is described as an example. The effective refractive index neff(λ) at the wavelength λ is given by equation (4) as described above. In equation (4), the refractive index n 1  and the refractive index n 2  are functions of λ. 
     Furthermore, the height H of the projected portion (the depth of the recess portion) of the uneven pattern at which the reflection on the upper surface of the intermediate layer is minimum is a condition under which the lights cancel each other out due to interference, and may be expressed by following equation (20). In Equation (20), λ is the wavelength in vacuum, and the effective refractive index neff(λ) is the function of the wavelength, so that the height H also is a function of the wavelength. 
     
       
         
           
             
               
                 
                   [ 
                   
                     Equation 
                     ⁢ 
                     
                         
                     
                     ⁢ 
                     20 
                   
                   ] 
                 
               
               
                 
                     
                 
               
             
             
               
                 
                   
                     H 
                     ⁡ 
                     
                       ( 
                       λ 
                       ) 
                     
                   
                   = 
                   
                     λ 
                     
                       4 
                       ⁢ 
                       
                         
                           n 
                           eff 
                         
                         ⁡ 
                         
                           ( 
                           λ 
                           ) 
                         
                       
                     
                   
                 
               
               
                 
                   ( 
                   20 
                   ) 
                 
               
             
           
         
       
     
     The wavelength in the pixel has a width. For example, the wavelength of the light received by the B pixel has a width of 400 to 500 nm. Because of this width, the height H (the thickness of the intermediate first layer  37 ) is determined by any of the following determining methods. 
     (Determining Method C-1) 
     For each of the R pixel, G pixel, and B pixel, an average value weighted by the spectral sensitivity W(λ) is used, and a value obtained by following equation (21) is set to the height H of the projected portion  37   b  of the medium  2  (intermediate first layer  37 ). 
     
       
         
           
             
               
                 
                   [ 
                   
                     Equation 
                     ⁢ 
                     
                         
                     
                     ⁢ 
                     21 
                   
                   ] 
                 
               
               
                 
                     
                 
               
             
             
               
                 
                   H 
                   = 
                   
                     
                       
                         ∫ 
                         
                           λ 
                           min 
                         
                         
                           λ 
                           max 
                         
                       
                       ⁢ 
                       
                         
                           
                             
                               w 
                               ⁡ 
                               
                                 ( 
                                 λ 
                                 ) 
                               
                             
                             ⁢ 
                             λ 
                           
                           
                             
                               n 
                               eff 
                             
                             ⁡ 
                             
                               ( 
                               λ 
                               ) 
                             
                           
                         
                         ⁢ 
                         d 
                         ⁢ 
                         
                             
                         
                         ⁢ 
                         λ 
                       
                     
                     
                       4 
                       ⁢ 
                       
                         
                           ∫ 
                           
                             λ 
                             min 
                           
                           
                             λ 
                             max 
                           
                         
                         ⁢ 
                         
                           
                             w 
                             ⁡ 
                             
                               ( 
                               λ 
                               ) 
                             
                           
                           ⁢ 
                           d 
                           ⁢ 
                           
                               
                           
                           ⁢ 
                           λ 
                         
                       
                     
                   
                 
               
               
                 
                   ( 
                   21 
                   ) 
                 
               
             
           
         
       
     
     (Determining Method C-2) 
     For each of the R pixel, G pixel, and B pixel, it is optimized for the peak value λp of the spectral sensitivity W(λ), and a value obtained by following equation (22) is set to the height H of the projected portion  37   b  of the medium  2  (intermediate first layer  37 ). 
     
       
         
           
             
               
                 
                   [ 
                   
                     Equation 
                     ⁢ 
                     
                         
                     
                     ⁢ 
                     22 
                   
                   ] 
                 
               
               
                 
                     
                 
               
             
             
               
                 
                   H 
                   = 
                   
                     
                       λ 
                       p 
                     
                     
                       4 
                       ⁢ 
                       
                         
                           n 
                           eff 
                         
                         ⁡ 
                         
                           ( 
                           
                             λ 
                             p 
                           
                           ) 
                         
                       
                     
                   
                 
               
               
                 
                   ( 
                   22 
                   ) 
                 
               
             
           
         
       
     
     (Determining Method C-3) 
     For each of the R pixel, G pixel, and B pixel, a threshold of the spectral sensitivity W(λ) is specified, and a value obtained by following equation (23) is set to the height H of the projected portion  37   b  of the medium  2  (intermediate first layer  37 ). 
     
       
         
           
             
               
                 
                   [ 
                   
                     Equation 
                     ⁢ 
                     
                         
                     
                     ⁢ 
                     23 
                   
                   ] 
                 
               
               
                 
                     
                 
               
             
             
               
                 
                   H 
                   = 
                   
                     
                       
                         λ 
                         L 
                       
                       
                         4 
                         ⁢ 
                         
                           
                             n 
                             eff 
                           
                           ⁡ 
                           
                             ( 
                             
                               λ 
                               L 
                             
                             ) 
                           
                         
                       
                     
                     ≤ 
                     H 
                     ≤ 
                     
                       
                         λ 
                         U 
                       
                       
                         4 
                         ⁢ 
                         
                           
                             n 
                             eff 
                           
                           ⁡ 
                           
                             ( 
                             
                               λ 
                               U 
                             
                             ) 
                           
                         
                       
                     
                   
                 
               
               
                 
                   ( 
                   23 
                   ) 
                 
               
             
           
         
       
     
     The height H (the thickness of the intermediate first layer  37 ) of the projected portion  37   b  is set by any one of the determining methods C-1 to C-3. 
     As described above, the determining method of the space occupancy f may be determined by seven determining methods A-1 to A-4 and B-1 to B-3, and the determining method of the height H of the intermediate layer may be determined by three determining methods of C-1 to C-3. Therefore, in a case of combining the determining methods of the space occupancy f and the determining methods of the height H of the intermediate layer, there are 21 combinations. 
     From the 21 combinations, the space occupancy f and the height H may be determined by the optimum combination. For example, they may also be determined by calculating and simulating the combination of the space occupancy f and the height H with which the maximum reflection ratio or average reflection ratio in the wavelength region is the minimum value. 
     &lt;Effect by Forming Uneven Pattern&gt; 
     In this manner, for example, as illustrated in  FIG. 2 , in the solid-state imaging device  11  to which the present technology is applied, the Si substrate  38  with the refractive index n 0 , the intermediate second layer  36  with the refractive index n 1 , and the oxide film  35  with the refractive index n 0  are stacked, and the intermediate first layer  37  and the intermediate second layer  36  include the layer serving as the reflection ratio adjusting layer because they are formed to have the fine uneven structure. 
     With reference to  FIG. 18 , it is described that the solid-state imaging device  11  having the uneven structure may reduce the reflection ratio as compared with a solid-state imaging device not having the uneven structure. In a graph illustrated in  FIG. 18 , the wavelength is plotted along the abscissa and the light intensity reflection ratio is plotted along the ordinate. Furthermore, in  FIG. 18 , a line connecting lozenges (a graph without unevenness) represents the light intensity reflection ratio in the solid-state imaging device not having the uneven structure, and a line connecting squares (a graph with unevenness) represents the light intensity reflection ratio in the solid-state imaging device  11  having the uneven structure. 
     Furthermore, the graph with unevenness illustrated in  FIG. 18  illustrates a result of measurement with the solid-state imaging device  11  in which the uneven structure is optimized for the vacuum wavelength of 550 nm. Specifically, the light intensity reflection ratio measured by the solid-state imaging device  11  having the space occupancy f of 0.385 and the height H of 54 nm is illustrated. Furthermore, the light intensity reflection ratio in a case where the medium  1  is ALSO  3 , the medium  2  is Si, and it is measured at the time of normal incidence is illustrated. 
     In the graph illustrated in  FIG. 18 , the lower the light intensity reflection ratio is, the more the reflection is reduced. From the graph in  FIG. 18 , it may be understood that the light intensity reflection ratio is lower and the reflection is suppressed in the graph with the unevenness than in the graph without the unevenness in all the wavelength regions. In other words, it may also be understood from the graph in  FIG. 18  that the solid-state imaging device  11  having the uneven structure may suppress the reflection more than the solid-state imaging device having no uneven structure in the entire wavelength region. 
     Furthermore, referring to the graph with the unevenness of the solid-state imaging device  11  having the uneven structure, it may be understood that the light intensity reflection ratio is the lowest at the wavelength of 550 nm in the graph with the unevenness. It is understood that the reflection may be suppressed the most at the optimized wavelength according to the solid-state imaging device  11  in which the uneven structure is optimized for the vacuum wavelength of 550 nm as described above. 
     In this manner, by forming the uneven structure, that is, by forming the reflection ratio adjusting layer in the solid-state imaging device  11 , the reflection may be reduced. Furthermore, by optimizing the uneven structure, the reflection at the optimized wavelength may be surely reduced. 
     A fact that the reflection may be further reduced by having the uneven structure and optimizing the height H and the space occupancy f thereof is described. 
     A graph illustrated in  FIG. 19  is a graph illustrating the reflection ratio when optimizing the space occupancy f for the vacuum wavelength of 550 nm and optimizing the height H for each of the R pixel, the G pixel, and the B pixel. 
     The graph illustrated in  FIG. 19  is a graph in a case where it is set that 
     the optimum height H=41.5 nm for λ 0 =450 nm in the B pixel, 
     the optimum height H=53.8 nm for λ 0 =550 nm in the G pixel, and 
     the optimum height H=66.0 nm for λ 0 =650 nm in the R pixel. 
     In  FIG. 19 , a line connecting lozenges (referred to as a graph B) represents the light intensity reflection ratio in the B pixel, a line connecting squares (referred to as a graph G) represents the light intensity reflection ratio in the G pixel, and a line connecting triangles (referred to as a graph R) represents the light intensity reflection ratio in the R pixel. 
     With reference to the graph with the unevenness illustrated in  FIG. 18  and the graph B illustrated in FIG.  19 , it may be understood that, in a range of the effective wavelength region of the B pixel of 400 to 500 nm, the maximum reflection ratio decreases from 19% ( FIG. 18 ) to 3.7% ( FIG. 19 ). 
     Similarly, with reference to the graph with the unevenness illustrated in  FIG. 18  and the graph G illustrated in  FIG. 19 , it may be understood that, in a range of the effective wavelength region of the G pixel of 500 to 600 nm, the maximum reflection ratio is substantially the same and is 1.0%. Since the graph with unevenness illustrated in  FIG. 18  is a result of measurement with pixels having a structure optimized for the vacuum wavelength of 550 nm in the effective wavelength region of the G pixel of 500 to 600 nm, the reflection ratio is substantially the same. 
     Similarly, with reference to the graph with the unevenness illustrated in  FIG. 18  and the graph R illustrated in  FIG. 19 , it may be understood that, in a range of the effective wavelength region of the R pixel of 600 to 700 nm, the maximum reflection ratio decreases from 3.4% ( FIG. 18 ) to 0.6% ( FIG. 19 ). 
     In this manner, it is confirmed that the reflection may be suppressed by optimizing the height H for each of the R pixel, the G pixel, and the B pixel. 
     The graph illustrated in  FIG. 20  is a graph illustrating the reflection ratio when the space occupancy f and the height H are optimized for each of the R pixel, the G pixel, and the B pixel. The space occupancy f may be optimized by changing the hole size (the diameter D of the projected portion  37   b ). 
     The graph illustrated in  FIG. 20  is a graph in a case where it is set that 
     the optimum space occupancy f=0.360 and the optimum height H=40.5 nm for λ 0 =450 nm in the B pixel, 
     the optimum space occupancy f=0.384 and the optimum height H=53.8 nm for λ 0 =550 nm in the G pixel, and 
     the optimum space occupancy f=0.394 and the optimum height H=66.6 nm for λ 0 =650 nm in the R pixel. 
     In  FIG. 20 , a line connecting lozenges (referred to as a graph B′) represents the light intensity reflection ratio in the B pixel, a line connecting squares (referred to as a graph G′) represents the light intensity reflection ratio in the G pixel, and a line connecting triangles (referred to as a graph R′) represents the light intensity reflection ratio in the R pixel. 
     With reference to the graph with the unevenness illustrated in  FIG. 18  and the graph B′ illustrated in  FIG. 20 , it may be understood that, in a range of the effective wavelength region of the B pixel of 400 to 500 nm, the maximum reflection ratio decreases from 19% ( FIG. 18 ) to 3.6% ( FIG. 20 ). 
     Similarly, with reference to the graph with the unevenness illustrated in  FIG. 18  and the graph G′ illustrated in  FIG. 20 , it may be understood that, in a range of the effective wavelength region of the G pixel of 500 to 600 nm, the maximum reflection ratio is substantially the same and is 1.0%. Since the graph with unevenness illustrated in  FIG. 18  is a result of measurement with pixels having a structure optimized for the vacuum wavelength of 550 nm in the effective wavelength region of the G pixel of 500 to 600 nm, the reflection ratio is substantially the same. 
     Similarly, with reference to the graph with the unevenness illustrated in  FIG. 18  and the graph R′ illustrated in  FIG. 20 , it may be understood that, in a range of the effective wavelength region of the R pixel of 600 to 700 nm, the maximum reflection ratio decreases from 3.4% ( FIG. 18 ) to 0.6% ( FIG. 20 ). 
     The graph in  FIG. 19  is the result of optimizing the height H for each pixel, and the graph in  FIG. 20  is the result of optimizing the height H and the space occupancy f for each pixel. The graph illustrated in  FIG. 19  and the graph illustrated in  FIG. 20  are substantially the same. 
     With this arrangement, it may be understood that the space occupancy f is not required to be optimized in each pixel because substantially the same result may be obtained in a case where the height H is optimized for each pixel and a case where the height H and the space occupancy f are optimized for each pixel. 
     That is, by optimizing the height H for each pixel, an effect on reflection prevention is obtained. Then, by optimizing the space occupancy f for each pixel also, it is possible to more certainly obtain the effect on reflection prevention. This is further described with reference to  FIG. 21 . 
     A following condition under which the lights cancel each other out by the interference is important for the height H at which the reflection is minimized on the upper surface of the intermediate layer. Therefore, it is considered to optimize the space occupancy f of each pixel so that the height H is common for each pixel and is close to equation (20) above. 
     Equation (20) expresses the height H at which the reflection is minimum on the upper surface of the intermediate layer as described above, and is an equation expressing the condition under which the lights cancel each other out due to the interference. 
     A graph illustrated in  FIG. 21  is a graph representing a result (reflection ratio) of the optimization of the space occupancy f so as to satisfy equation (20) while fixing the height H of the R pixel, the G pixel, and the B pixel at the height H optimized at λ 0 =550 nm. Note that the effective refractive index neff included in equation (20) satisfies, for example, equation (4), and equation (4) includes the space occupancy f, so that it is required to set the space occupancy f so as to satisfy equation (4) in a case of setting the space occupancy f so as to satisfy equation (20). 
     The graph illustrated in  FIG. 21  is a graph in a case where it is set that 
     the optimum space occupancy f=0.680 for λ 0 =450 nm in the B pixel, 
     the optimum space occupancy f=0.380 for λ 0 =550 nm in the G pixel, and 
     the optimum space occupancy f=0.181 for λ 0 =650 nm in the R pixel. 
     In  FIG. 21 , a line connecting lozenges (referred to as a graph B″) represents the light intensity reflection ratio in the B pixel, a line connecting squares (referred to as a graph G″) represents the light intensity reflection ratio in the G pixel, and a line connecting triangles (referred to as a graph R″) represents the light intensity reflection ratio in the R pixel. 
     With reference to the graph with the unevenness illustrated in  FIG. 18  and the graph B″ illustrated in  FIG. 21 , it may be understood that, in a range of the effective wavelength region of the B pixel of 400 to 500 nm, the maximum reflection ratio is not sufficiently decreased. 
     Similarly, with reference to the graph with the unevenness illustrated in  FIG. 18  and the graph G″ illustrated in  FIG. 21 , it may be understood that, in a range of the effective wavelength region of the G pixel of 500 to 600 nm, the maximum reflection ratio is substantially the same and is 1.0%. Since the graph with unevenness illustrated in  FIG. 18  is a result of measurement with pixels having a structure optimized for the vacuum wavelength of 550 nm in the effective wavelength region of the G pixel of 500 to 600 nm, the reflection ratio is substantially the same. 
     Similarly, with reference to the graph with the unevenness illustrated in  FIG. 18  and the graph R″ illustrated in  FIG. 21 , it may be understood that, in a range of the effective wavelength region of the R pixel of 600 to 700 nm, the maximum reflection ratio is not sufficiently decreased. 
     In other words, from the graph illustrated in  FIG. 21 , it may be understood that the antireflective effect is insufficient except for the G pixel despite the fact that the space occupancy f must be significantly changed for each of the R pixel, the G pixel, and the B pixel. 
     From above, it is understood that optimizing the height H of the uneven structure for each of the R pixel, G pixel, and B pixel is more effective from the viewpoint of reflection prevention. In the following description, optimization of the height H for each of the R pixel, G pixel, and B pixel is mainly described. 
     &lt;Regarding First Manufacturing Method of Solid-State Imaging Device Having Uneven Structure&gt; 
     Next, the manufacturing method of the solid-state imaging device  11  in which the Si substrate  38  with the refractive index n 0 , the intermediate second layer  36  with the refractive index n 1 , and the oxide film  35  with the refractive index n 0  are stacked and the intermediate first layer  37  and the intermediate second layer  36  include the layer serving as the reflection ratio adjusting layer formed to have the fine uneven structure as illustrated in  FIG. 2  is described. 
     In the following description of the manufacture of the solid-state imaging device  11 , a case of forming the pixel array unit of a Bayer array as illustrated in  FIG. 22  is described as an example. In other words, a case of forming the pixel array unit in which the G pixels are arranged in upper left and lower right, the B pixel is arranged in upper right, and the R pixels is arranged in lower left when four pixels of two by two are set as one unit is described as an example. 
     Furthermore, a case where one pixel has a size of 1.4 μm by 1.4 μm is described as an example. Furthermore, a case where the pattern of the uneven structure has the pitch P of 40 nm and the diameter D of the hole size of 26 nm as illustrated in a right view in  FIG. 22  is described as an example. 
     Note that the numerical values herein listed are only examples and are not limitative. In other words, the present technology may also be applied to pixels having a size other than the above-mentioned size. Furthermore, in the following description, similarly, the numerical values are only examples and are not limitative. Therefore, it is also possible to manufacture the solid-state imaging device  11  by applying the present technology and appropriately changing the numerical value. 
     With reference to  FIGS. 23 to 25 , a first manufacturing method of the solid-state imaging device  11  having the uneven structure is described. In the drawing, a left view illustrates the R pixel, a center view illustrates the G pixel, and a right view illustrates the B pixel. 
     At step S 11  ( FIG. 23 ), a substrate including a hole (recess portion) of a predetermined size is prepared. The substrate is a substrate which is already subjected to treatment described below. 
     First, when manufacturing a backside irradiation type imaging device, after a photodiode, a wiring layer and the like are formed, the substrate (Si substrate  38 ) reversed and joined to a support substrate. A surface of the substrate after the support substrate is joined is flat with Si. On the flat Si substrate  38 , an SiO2 film is deposited to a thickness of 30 nm by chemical vapor deposition (CVD) or atomic layer deposition (ALD) technology. 
     Moreover, PS-r-PMMA (a ratio of the number of Monomers between PS and PMMA is 7:3, for example) being random copolymer is spin-coated thereon and baked to form a thickness of 8 nm. This adjusts to the surface energy suitable for the self assembly. 
     Moreover, PS-b-PMMA (a ratio of the number of monomers between PS and PMMA is 7:3, for example, and length of molecule is about 40 nm) being block copolymer is spin-coated thereon and baked to form a thickness of 25 nm. Thereafter, the substrate is baked in an N2 atmosphere at 250° C. for five minutes. As a result, not only solvent remaining on the PS-b-PMMA coated film is dried but also microphase separation may be promoted. As a result of the self assembly, a PMMA area becomes a periodic hole array. 
     Moreover, ultraviolet light (UV light) is applied to an upper portion of the PS-b-PMMA film in an N2 atmosphere. As a result, binding of PMMA is cut while PS is crosslinked. When the PS-b-PMMA film is developed with isopropyl alcohol (IPA), only PMMA dissolves, and the hexagonal lattice hole array at a pitch of 40 nm and with a diameter of 26 nm is formed on the entire surface of the substrate. Although the grain boundary is generated as described above, this is not problematic due to an averaging effect within the pixel. 
     Next, PS-r-PMMA and the SiO2 film are etched by a dry etching technology. Moreover, Si is etched by a dry etching technology. The SiO2 film is removed by wet etching or dry etching technology. As a result, the cylindrical hole serving as a source of the uneven structure is formed on the Si substrate  38 . 
     By adjusting a condition of dry etching the SiO2 film and Si, it is possible to make the hole diameter (diameter) of the cylindrical hole in Si 26 nm. By forming in this manner, it is possible to form such that the space occupancy f of the cylindrical hole corresponds to 0.384. Also, the height (depth) of the cylindrical hole at this stage is 66 nm. 
     The Si substrate  38  subjected to the processes heretofore is prepared at step S 11 . As illustrated at step S 11  in  FIG. 23 , in a cross section, a portion which becomes the recess portion  37   a  (which is not yet formed at a desired height H at this point of time) is formed on the Si substrate  38 . Furthermore, the height H of the portion (cylinder) which becomes the recess portion  37   a  is 66 nm, and the diameter D of the hole is 26 nm. 
     At this stage at step S 11 , the sizes of the respective cylinders of the R pixel, G pixel, and B pixel are still the same. At a subsequent step, this is formed to have the height H optimized for each pixel. 
     Note that there may be a cylinder at a boundary of the R pixel, G pixel, or B pixel. 
     At step S 12 , positive type resist for i-line  201  is applied to an entire surface. The resist  201  is applied so that the hole being the cylinder is filled with the resist  201  and the height from the Si surface becomes 300 nm. 
     At step S 13  ( FIG. 24 ), an i-line exposure device is used to expose a gray tone mask  211  on the resist  201 . The gray tone mask  211  is spread with a pattern of a fine pitch not larger than a diffraction limit. Furthermore, mask transmittance of the gray tone mask  211  is determined according to the aperture ratio. 
     An aperture ratio of a gray tone mask  211 R on the R pixel area is set to be low so that the resist  201  on the upper portion of the Si substrate  38  thickly remains. 
     An aperture ratio of a gray tone mask  211 G on the G pixel area is set to be medium so that the resist  201  on the upper portion of the Si substrate  38  thinly remains. 
     An aperture ratio of a gray tone mask  211 B on the B pixel area is set to be high so that the resist  201  on the upper portion of the Si substrate  38  is removed and only the resist  201  on a bottom of the hole formed on the Si substrate  38  remains. 
     By changing the aperture ratio of the aperture of the gray tone mask  211  for each pixel in this manner, it is possible to adjust an amount (thickness) of the resist  201  remaining on the Si substrate  38 . 
     When the resist  201  is developed after the exposure, as illustrated at step S 14  ( FIG. 24 ), the thickness of the resist  201  varies among the R pixel, the G pixel, and the B pixel. 
     At step S 15 , the entire surface of the Si substrate  38  is etched under a condition that both the Si substrate  38  and the resist  201  are etched. Since the thickness of the resist  201  varies among the R pixel, the G pixel, and the B pixel, when the etching is executed, etching on the Si substrate  38  starts from the B pixel. 
     As the etching of the upper portion of the Si substrate  38  of the B pixel progresses, the etching of the upper portion of the Si substrate  38  of the G pixel is also started. In other words, when the resist  201  on the upper portion of the Si substrate  38  of the G pixel is etched, Si on the upper portion of the Si substrate  38  of the G pixel is subsequently etched. 
     Moreover, while the B pixel and the G pixel are being etched in this manner, the R pixel is also etched. Since the R pixel is etched in a state where the resist  201  is thickly formed, the resist  201  is etched, but a portion of Si of the Si substrate  38  of the R pixel is not etched. 
     Furthermore, the bottom portion of the hole of each of the R pixel, the G pixel, and the B pixel is maintained in a state of being covered with the resist  201  even during etching, so that the bottom portion of the hole is remained without being etched until the end of etching. 
     By changing the thickness of the resist  201 , it is possible to change an amount by which the Si substrate  38  of each of the R pixel, the G pixel, and the B pixel is etched. In this case, it is possible that the etching amount of the Si substrate  38  of the B pixel is large, the etching amount of the Si substrate  38  of the G pixel is medium, and the etching amount of the Si substrate  38  of the R pixel is small. 
     After such etching is performed, the remaining resist  201  is removed at step S 15 . The Si substrate  38  after the resist  201  is removed is as illustrated at step S 15  in  FIG. 24 . 
     The height H (depth) of the hole formed in the Si substrate  38  corresponding to the R pixel is 66 nm. Furthermore, the height H (depth) of the hole formed in the Si substrate  38  corresponding to the G pixel is 54 nm. Furthermore, the height H (depth) of the hole formed in the Si substrate  38  corresponding to the B pixel is 42 nm. 
     The height H of the hole is a value set as described above. For example, this is the value set under any one of the conditions C-1 to C-3. 
     In this manner, a process condition is herein adjusted so that the height H of the R pixel is 66 nm, the height H of the G pixel is 54 nm, and the height H of the B pixel is 42 nm. At such step, the height of the hole of each pixel may be changed, and the condition at each step described above, for example, the size of the aperture of the gray tone mask  211 , etching strength, time, and the like are adjusted such that the desired hole height is realized. 
     As step S 16  ( FIG. 25 ), Al2O3 is deposited on the Si substrate  38  by the ALD technology. Since the diameter D of the cylindrical hole is 26 nm, this is deposited until the hole is filled and the thickness on the Si substrate  38  becomes 15 nm. A state in which this is deposited in this manner is illustrated at step S 16  in  FIG. 25 . The deposited Al2O3 forms the intermediate second layer  36  ( FIG. 2 ). 
     Furthermore, at the steps so far, the fine uneven structure is formed on the Si substrate  38 , and the intermediate first layer  37  and the intermediate second layer  36  are formed. Therefore, at the steps so far, since the intermediate first layer  37  and the intermediate second layer  36  are formed with the fine uneven structure, the layer serving as the reflection ratio adjusting layer is formed. 
     At step S 17  ( FIG. 25 ), the SiO2 film is deposited on the intermediate second layer  36  by the CVD technology, and the surface is planarized by the CMP technology. Then, the color filter  32  of the corresponding color is formed in each of the R pixel, the G pixel, and the B pixel. The SiO2 film deposited on the intermediate second layer  36  forms the oxide film  35 . 
     As illustrated in  FIG. 25 , the height of the Si substrate  38  of the R pixel, the height of the Si substrate  38  of the G pixel, and the height of the Si substrate  38  of the B pixel are different from one another, so that the height of the intermediate second layer  36  deposited thereon so as to have the thickness of 15 nm is also different. 
     The oxide film  35  is deposited so as to absorb this height and planarize, and the color filter  32  is formed on the planarized oxide film  35 . 
     Note that, as illustrated in  FIG. 1 , in a case of manufacturing the solid-state imaging device  11  having the light-shielding film  34 , as a step between step S 16  and step S 17 , the light-shielding film  34  is formed on the intermediate second layer  36 . After the light-shielding film  34  is formed, the planarizing film  33  is formed in order to planarize, and thereafter the color filter  32  is formed. 
     In this manner, by manufacturing the solid-state imaging device  11  so that the height H of the hole of each of the R pixel, G pixel, and B pixel becomes the optimized height H, the manufactured solid-state imaging device  11  may be, for example, the solid-state imaging device  11  having the characteristic as illustrated in  FIG. 19 . 
     In other words, this may be made the solid-state imaging device  11  capable of significantly reducing the reflection light from the Si substrate  38  in all of the R pixel, the G pixel, and the B pixel. According to such solid-state imaging device  11 , it is possible to prevent the stray light (ghost flare) from being reflected in the image taken by the solid-state imaging device  11  and to make the solid-state imaging device  11  capable of improving the image quality. 
     &lt;Regarding Second Manufacturing Method of Solid-State Imaging Device Having Uneven Structure&gt; 
       FIG. 26  illustrates the solid-state imaging device  11  manufactured by the first manufacturing method of the solid-state imaging device having the uneven structure described above.  FIG. 26  illustrates the solid-state imaging device  11  of two adjacent pixels. Furthermore, in  FIG. 26 , the R pixel and G pixel are illustrated as the adjacent pixels. 
     The height of the hole of the R pixel (the height H of the projected portion  37   b ) is 66 nm, and the height of the hole of the G pixel (the height H of the projected portion  37   b ) is 54 nm. Here, in a case where a boundary between the R pixel and G pixel is focused on, the height of the Si substrate  38  drastically changes at the boundary (here, this changes from 66 nm to 54 nm). 
     That is, there is a step on the Si substrate  38  at the boundary between the R pixel and the G pixel. Furthermore, since there is the step on the Si substrate  38  also has the step, there also is a step on the intermediate second layer  36  deposited on the Si substrate  38 . 
     Such step might cause irregular reflection of light at a corner of the step to cause stray light. Manufacture (referred to as a second manufacturing method) of the solid-state imaging device  11  in which the step on the Si substrate  38  at the boundary is reduced is described. 
     First, a structure of the solid-state imaging device  11  in which the step on the Si substrate  38  at the boundary is reduced is described with reference to  FIG. 27 . As in  FIG. 26 ,  FIG. 27  also illustrates the adjacent R pixel and G pixel (however, the color filter  32  and the like are not illustrated). 
     In  FIG. 26 , the pixel on the left side is the R pixel and the pixel on the right side is the G pixel. The height H of the projected portion  37   b  at the boundary between the R pixel and the G pixel is set to a height H 3 . The height of the projected portion  37   b  in a direction approaching from the boundary to the vicinity of the center of the R pixel (leftward direction in the drawing) changes to a height H 2  and a height H 1 . Furthermore, the height of the projected portion  37   b  in a direction approaching from the boundary to the vicinity of the center of the G pixel (rightward direction in the drawing) changes to a height H 4  and a height H 5 . 
     The heights E 1  to H 5  satisfy a following relationship.
 
Height  H 1&gt;height  H 2&gt;height  H 3&gt;height  H 4&gt;height  H 5
 
     In a case where the height H 1  on the R pixel side is set to 66 nm which is the optimum height in the R pixel and the height H 5  on the G pixel side is set to 54 nm which is the optimum height in the G pixel, and in a case where the above-described relationship is satisfied, the height of the projected portion  37   b  gradually changes from 66 nm to 54 nm at the boundary between the pixels. 
     By configuring so that the height of the projected portion  37   b  gradually changes at the boundary between the pixels in this manner, it is possible to configure such that drastic change in height is prevented, and it becomes possible to prevent generation of the stray light due to the step at the boundary between the pixels. 
     In a case of manufacturing the solid-state imaging device  11  in which the height of the projected portion  37   b  gradually changes at the boundary between the pixels in this manner, it is possible to form the projected portion  37   b  such that the height of the projected portion  37   b  gradually changes by adjusting the aperture of the gray tone mask  211 . 
     For example, the gray tone mask  211  as illustrated in  FIG. 28  is used. In an upper part in  FIG. 28 , a pixel group of one unit including four pixels of two by two is illustrated. An area straddling the boundary between the R pixel and the G pixel in this pixel group is set as an area  301 . Furthermore, a central area of the pixel group is set as an area  302 . 
     A gray tone mask  211 - 301  applied to the area  301  is illustrated in lower left in  FIG. 28  and a gray tone mask  211 - 302  applied to the area  302  is illustrated in lower right in  FIG. 28 . 
     The gray tone mask  211  is a mask the mask transmittance of which may be determined in accordance with the aperture ratio, for example, as illustrated at step S 13  in  FIG. 24 . For example, in a case where the aperture ratio is increased, the mask transmittance increases and the etching amount increases, and in a case where the aperture ratio is lowered, the mask transmittance decreases and the etching amount decreases. 
     Furthermore, as described with reference to steps S 13  to S 15  in  FIG. 24 , in a case where the aperture ratio of the gray tone mask  211  is increased, the height H of the projected portion  37   b  is lowered, and in a case where the aperture ratio of the gray tone mask  211  is decreased, the height H of the projected portion  37   b  is increased. 
     Therefore, for example, the aperture ratio of the gray tone mask  211  for forming the projected portion  37   b  of the height H 1  ( FIG. 27 ) (higher side projected portion  37   b ) may be made lower, and the aperture ratio of the gray tone mask  211  for forming the projected portion  37   b  of the height H 5  ( FIG. 27 ) (lower side projected portion  37   b ) may be made higher. 
     With reference to  FIG. 28 , the gray tone mask  211 - 301  is made the mask the aperture ratio of which gradually increases from a left side toward a right side (from the R pixel toward the G pixel). 
     The gray tone mask  211 - 302  is made the mask the aperture ratio of which gradually increases from the left side toward the right side (from the B pixel toward the G pixel) on an upper side. Similarly, the gray tone mask  211 - 302  is made the mask the aperture ratio of which gradually increases from the left side toward the right side (from the R pixel toward the G pixel) on a lower side. 
     The gray tone mask  211 - 302  is made the mask the aperture ratio of which gradually decreases from the upper side toward the lower side (from the G pixel toward the R pixel) on the left side. Similarly, the gray tone mask  211 - 302  is made the mask the aperture ratio of which gradually decreases from the upper side toward the lower side (from the B pixel toward the G pixel) on the right side. 
     In this manner, in a separation area between the pixels, as illustrated in  FIG. 28 , the aperture ratio (pattern sizes of the aperture and the light-shielding portion) of the gray tone mask  211  is continuously changed. At the time of the continuous change, for example, a motion average of a light-shielding ratio is set as a size of a new light-shielding pattern around a target pattern. 
     The solid-state imaging device  11  may be obtained in which the height H of the cylindrical hole formed in the Si substrate  38  also changes continuously in an area in which the aperture of the gray tone mask  211  is continuously changed and the height is changed as illustrated in  FIG. 27 . 
     In this manner, it is possible to suppress formation of the step on the Si substrate  38  at the boundary between the pixels. 
     &lt;Regarding Third Manufacturing Method of Solid-State Imaging Device Having Uneven Structure&gt; 
     As described with reference to  FIG. 26 , in a case of manufacturing the solid-state imaging device  11  by applying the first manufacturing method, the solid-state imaging device  11  has a portion (step) in which the height of the Si substrate  38  drastically changes at the boundary between the pixels. 
     Such step might cause irregular reflection of light at a corner of the step to cause stray light. Manufacture (referred to as a third manufacturing method) of the solid-state imaging device  11  in which the step on the Si substrate  38  at the boundary is reduced is described. 
     First, a structure of the solid-state imaging device  11  in which the step on the Si substrate  38  at the boundary is reduced is described with reference to  FIG. 29 . As in  FIG. 26 ,  FIG. 29  also illustrates the adjacent R pixel and G pixel (however, the color filter  32  and the like are not illustrated). 
     In  FIG. 29 , the pixel on the left side is the R pixel and the pixel on the right side is the G pixel. In an upper part in  FIG. 29 , a pixel group of one unit including four pixels of two by two is illustrated. In the pixel group, an area which straddles a boundary between the R pixel and G pixel is defined as an area  311 , and a structure of the pixels in this area  311  is illustrated in a lower view in  FIG. 29 . 
     As illustrated in the lower view in  FIG. 29 , a light-shielding wall  321  of, for example, SiO is formed at the boundary between the R pixel and the G pixel in the area  311 . By forming the light-shielding wall  321 , it is possible to prevent the height of the projected portion  37   b  from drastically changing at the boundary between the pixels. Therefore, it is possible to prevent the generation of the stray light caused by the step by eliminating the step. 
     Furthermore, by forming the light-shielding wall  321  between the pixels, it is possible to prevent color mixture due to oblique incident light. Therefore, the image quality may be improved. 
     Such light-shielding wall  321  is obtained such that, for example, after the circular hole (recess portion  37   a ) is formed in the Si substrate  38 , the Si substrate  38  in the area  311  including the boundary between the pixels is etched, and the etched portion is filled with SiO. 
     Thereafter, SiO other than that between the pixels is removed. At such step, the light-shielding wall  321  is formed between the pixels. Then, by depositing Al2O3 forming the intermediate second layer  36  on the Si substrate  38  and the light-shielding wall  321 , the solid-state imaging device  11  having the configuration illustrated in  FIG. 29  is manufactured. 
     Note that, although SiO is herein described as an example as a material of the light-shielding wall  321 , other material may also be used, and metal or the like may also be used, for example. 
     In this manner, it is possible to suppress formation of the step on the Si substrate  38  at the boundary between the pixels. Furthermore, since the formation of the step is suppressed, it is possible to reduce occurrence of adverse effects due to the step. 
     &lt;Regarding Fourth Manufacturing Method of Solid-State Imaging Device Having Uneven Structure&gt; 
     Another manufacturing method (fourth manufacturing method) of the solid-state imaging device  11  is described. In the following description of the fourth manufacturing method of the solid-state imaging device  11 , a case of forming the pixel array unit of the Bayer array as illustrated in  FIG. 22  is described as an example as in the first manufacturing method. 
     In other words, a case of forming the pixel array unit in which the G pixels are arranged in upper left and lower right, the B pixel is arranged in upper right, and the R pixels is arranged in lower left when four pixels of two by two are set as one unit is described as an example. Furthermore, a case where one pixel has a size of 1.4 μm by 1.4 μm is described as an example. Furthermore, a case where the pattern of the uneven structure has the pitch P of 40 nm and the diameter D of the hole size of 26 nm as illustrated in a right view in  FIG. 22  is described as an example. 
     Note that the numerical values herein listed are only examples and are not limitative. In other words, the present technology may also be applied to pixels having a size other than the above-mentioned size. Furthermore, in the following description, similarly, the numerical values are only examples and are not limitative. Therefore, it is also possible to manufacture by changing the numerical values as appropriate. 
     With reference to  FIGS. 30 to 32 , the fourth manufacturing method of the solid-state imaging device having the uneven structure is described. In the drawing, a left view illustrates the R pixel, a center view illustrates the G pixel, and a right view illustrates the B pixel. 
     At step S 41  ( FIG. 30 ), a substrate including holes (recess portions) of a predetermined size is prepared. This substrate may be substantially the same substrate as that prepared at step S 11  ( FIG. 23 ) of the first manufacturing method except that a part of the SiO2 film remains on the Si substrate  38 . Here, the manufacture of the substrate prepared at step S 41  is described again. 
     First, when manufacturing a backside irradiation type imaging device, after a photodiode, a wiring layer and the like are formed, the substrate (Si substrate  38 ) is reversed and joined to a support substrate. A surface of the substrate after the support substrate is joined is flat with Si. On the flat Si substrate  38 , an SiO2 film is deposited to a thickness of 30 nm by chemical vapor deposition (CVD) or atomic layer deposition (ALD) technology. 
     Moreover, PS-r-PMMA (a ratio of the number of monomers between PS and PMMA is 7:3, for example) being random copolymer is spin-coated thereon and baked to form a thickness of 8 nm. This adjusts to the surface energy suitable for the self assembly. 
     Moreover, PS-b-PMMA (a ratio of the number of monomers between PS and PMMA is 7:3, for example, and length of molecule is about 40 nm) being block copolymer is spin-coated thereon and baked to form a thickness of 25 nm. Thereafter, the substrate is baked in an N2 atmosphere at 250° C. for five minutes. As a result, not only solvent remaining on the PS-b-PMMA coated film is dried but also microphase separation may be promoted. As a result of the self assembly, a PMMA area becomes a periodic hole array. 
     Moreover, UV light is applied to an upper portion on the PS-b-PMMA film in an N2 atmosphere. As a result, binding of PMMA is cut while PS is crosslinked. When the PS-b-PMMA film is developed with isopropyl alcohol (IPA), only PMMA dissolves, and the hexagonal lattice hole array at a pitch of 40 nm and with a diameter of 26 nm is formed on the entire surface of the substrate. Although the grain boundary is generated as described above, this is not problematic due to an averaging effect within the pixel. 
     Next, PS-r-PMMA and the SiO2 film are etched by a dry etching technology. Moreover, Si is etched by a dry etching technology. At such a step, a cylindrical hole formed in the Si substrate  38 . At that time, the SiO2 film is left by about 10 nm. In other words, as illustrated at step S 41  in  FIG. 30 , a substrate on which an SiO2 film  411  with a thickness of 10 nm is formed in a portion of the projected portion  37   b  of the Si substrate  38  is manufactured. 
     By adjusting a condition of dry etching the SiO2 film and Si, it is possible to make the hole diameter (diameter) of the cylindrical hole in Si 26 nm. By forming in this manner, it is possible to form such that the space occupancy f of the cylindrical hole corresponds to 0.384. Also, the height (depth) of the cylindrical hole at this stage is set to 42 nm. 
     The Si substrate  38  subjected to the processes heretofore is prepared at step S 41 . As illustrated at step S 41  in  FIG. 30 , in a cross section, a portion which becomes the recess portion  37   a  (which is not yet formed at a desired height H at this point of time) is formed in the Si substrate  38 . Furthermore, the height H of the portion (cylinder) to be the recess portion  37   a  is 42 nm, and the diameter D of the hole is 26 nm. 
     At this stage at step S 41 , the sizes of the respective cylinders of the R pixel, G pixel, and B pixel are still the same. At a subsequent step, this is formed to have the height H optimized for each pixel. 
     Note that there may be a cylinder at a boundary of the R pixel, G pixel, or B pixel. 
     At step S 42 , positive type resist  421  for i-line is applied to the entire surface. The resist  421  is applied such that the cylinder hole is filled with the resist  421  and the height from the Si surface is 300 nm. 
     At step S 43  ( FIG. 31 ), the i-line exposure device is used to expose a gray tone mask  431  on the resist  421 . The gray tone mask  431  is spread with a pattern of a fine pitch not larger than a diffraction limit. Furthermore, mask transmittance of the gray tone mask  431  is determined according to the aperture ratio. 
     An aperture ratio of a gray tone mask  431 R on the R pixel area is set to be high so that the resist  421  is completely dissolved. 
     An aperture ratio of a gray tone mask  431 G on the G pixel area is set to be medium so that resist  431 G on the upper portion of the Si substrate  38  is removed and only the resist  431 G on a bottom of the hole formed in the Si substrate  38  remains. 
     An aperture ratio of a gray tone mask  431 B on the B pixel area is set to be low so that the resist  421  thickly remains also on the upper portion of the Si substrate  38 . 
     By changing the aperture ratio of the aperture of the gray tone mask  431  for each pixel in this manner, it is possible to adjust an amount of the resist  421  remaining on the Si substrate  38 . At this step, the Si substrate  38  is not etched, and only the resist  421  is etched. 
     When the resist  421  is developed after the exposure, as illustrated at step S 44  ( FIG. 31 ), the thickness of the resist  421  varies for each of the R pixel, the G pixel, and the B pixel. 
     At step S 45 , the entire surface of the substrate is etched under a condition that both the Si substrate  38  and the resist  421  are etched and the SiO2 film  411  is not etched. Since the thickness of the resist  421  varies among the R pixel, the G pixel, and the B pixel, when the etching is executed, the bottom portion of the cylindrical hole of the Si substrate  38  of the R pixel is first etched. 
     As the etching of the bottom portion of the cylindrical hole of the Si substrate  38  of the R pixel progresses, the etching of the cylindrical hole of the Si substrate  38  of the G pixel also progresses. In other words, while the Si substrate  38  of the bottom portion of the cylindrical hole of the Si substrate  38  of the R pixel is etched, the resist  421  of the bottom portion of the cylindrical hole of the Si substrate  38  of the G pixel is etched. Then, when the etching of the resist  421  in the bottom portion of the cylindrical hole of the Si substrate  38  of the G pixel is finished, the Si substrate  38  in the bottom portion of the cylindrical hole of the Si substrate  38  of the G pixel is also subsequently etched. 
     Moreover, while the R pixel and the G pixel are being etched in this manner, the B pixel is also etched. Since the etching of the B pixel is performed in a state where the resist  421  is thickly formed, the resist  421  etched and the resist  421  is removed, but the Si substrate  38  of the B pixel is not etched. 
     By changing the thickness of the resist  421 , it is possible to change an amount by which the Si substrate  38  of each of the R pixel, the G pixel, and the B pixel is etched. In this case, it is possible that the etching amount of the Si substrate  38  of the R pixel is large, the etching amount of the Si substrate  38  of the G pixel is medium, and the etching amount of the Si substrate  38  of the B pixel is small (to be zero). 
     After such etching is performed, the remaining resist  421  and the SiO2 film  411  are removed at step S 45 . The Si substrate  38  after the resist  421  and the SiO2 film  411  are removed is as illustrated at step S 45  in  FIG. 31 . 
     The height H (depth) of the hole formed in the Si substrate  38  corresponding to the R pixel is 66 nm. Furthermore, the height H (depth) of the hole formed in the Si substrate  38  corresponding to the G pixel is 54 nm. Furthermore, the height H (depth) of the hole formed in the Si substrate  38  corresponding to the B pixel is 42 nm. 
     The height H of the hole is a value set as described above. For example, this is the value set under any one of the conditions C-1 to C-3. 
     In this manner, a process condition is herein adjusted so that the height H of the R pixel is 66 nm, the height H of the G pixel is 54 nm, and the height H of the B pixel is 42 nm. At such step, the height of the hole of each pixel may be changed, and the condition at each step described above, for example, the size of the aperture of the gray tone mask  431 , etching strength, time, and the like are adjusted such that the desired hole height is realized. 
     In a case where the cylindrical hole (uneven structure) is formed in the Si substrate  38  in this manner, as illustrated at step S 45  in  FIG. 31 , the upper surface of the Si substrate  38  of the R pixel, the upper surface of the Si substrate  38  of the G pixel, and the upper surface of the Si substrate  38  of the B pixel are at the same height and there is no step between the pixels. 
     Unlike the solid-state imaging device  11  manufactured by the first manufacturing method, since there is no step at the boundary between the pixels, it is possible to suppress the generation of the stray light which might be generated due to the step. 
     As step S 46  ( FIG. 32 ), Al2O3 is deposited on the Si substrate  38  by the ALD technology. Since the diameter D of the cylindrical hole is 26 nm, Al2O3 is deposited until the hole is filled and the thickness on the Si substrate  38  becomes 15 nm. A state in which this is deposited in this manner is illustrated at step S 46  in  FIG. 32 . The deposited Al2O3 forms the intermediate second layer  36  ( FIG. 2 ). 
     At processes so far, the fine uneven structure is formed on the Si substrate  38 , and the intermediate first layer  37  and the intermediate second layer  36  are formed. Therefore, at such processes, since the intermediate first layer  37  and the intermediate second layer  36  are formed with the fine uneven structure, the layer serving as the reflection ratio adjusting layer may be formed. 
     At step S 47  ( FIG. 32 ), the SiO2 film is deposited on the intermediate second layer  36  by the CVD technology, and the surface is planarized by the CMP technology. Then, the color filter  32  of the corresponding color is formed in each of the R pixel, the G pixel, and the B pixel. The SiO2 film deposited on the intermediate second layer  36  forms the oxide film  35 . 
     Note that, as illustrated in  FIG. 1 , in a case of manufacturing the solid-state imaging device  11  including the light-shielding film  34 , as a step between step S 46  and step S 47 , the light-shielding film  34  is formed on the intermediate second layer  36 . After the light-shielding film  34  is formed, the planarizing film  33  is formed in order to planarize, and thereafter the color filter  32  is formed. 
     In this manner, by manufacturing the solid-state imaging device  11  so that the height H of the hole of each of the R pixel, G pixel, and B pixel becomes the optimized height H, the manufactured solid-state imaging device  11  may be, for example, the solid-state imaging device  11  having the characteristic as illustrated in  FIG. 19 . 
     In other words, this may be made the solid-state imaging device  11  capable of significantly reducing the reflection light from the Si substrate  38  in all of the R pixel, the G pixel, and the B pixel. According to such solid-state imaging device  11 , it is possible to prevent the stray light (ghost flare) from being reflected in the image taken by the solid-state imaging device  11  and to make the solid-state imaging device  11  capable of improving the image quality. 
     &lt;Regarding Fifth Manufacturing Method of Solid-State Imaging Device Having Uneven Structure&gt; 
     Another manufacturing method (fifth manufacturing method) of the solid-state imaging device  11  is described. In the following description of the fifth manufacturing method of the solid-state imaging device  11 , a case of forming the pixel array unit of the Bayer array as illustrated in  FIG. 22  is described as an example as in the first manufacturing method. 
     With reference to  FIGS. 33 to 34 , the fifth manufacturing method of the solid-state imaging device having the uneven structure is described. In the drawing, a left view illustrates the R pixel, a center view illustrates the G pixel, and a right view illustrates the B pixel. 
     At step S 51  ( FIG. 33 ), a substrate including holes (recess portions) of a predetermined size in the SiO2 film is prepared. The manufacture of the substrate prepared at step S 51  is described. 
     First, when manufacturing a backside irradiation type imaging device, after a photodiode, a wiring layer and the like are formed, the substrate (Si substrate  38 ) is reversed and joined to a support substrate. A surface of the substrate after the support substrate is joined is flat with Si. On the flat Si substrate  38 , an SiO2 film  511  is deposited to a thickness of 30 nm by chemical vapor deposition (CVD) or atomic layer deposition (ALD) technology. 
     Moreover, PS-r-PMMA (a ratio of the number of monomers between PS and PMMA is 7:3, for example) being random copolymer is spin-coated thereon and baked to form a thickness of 8 nm. This adjusts to the surface energy suitable for the self assembly. 
     Moreover, PS-b-PMMA (a ratio of the number of monomers between PS and PMMA is 7:3, for example, and length of molecule is about 40 nm) being block copolymer is spin-coated thereon and baked to form a thickness of 25 nm. Thereafter, the substrate is baked in an N2 atmosphere at 250° C. for five minutes. As a result, not only solvent remaining on the PS-b-PMMA coated film is dried but also microphase separation may be promoted. As a result of the self assembly, a PMMA area becomes a periodic hole array. 
     Moreover, UV light is applied to an upper portion on the PS-b-PMMA film in an N2 atmosphere. As a result, binding of PMMA is cut while PS is crosslinked. When the PS-b-PMMA film is developed with isopropyl alcohol (IPA), only PMMA dissolves, and the hexagonal lattice hole array at a pitch of 40 nm and with a diameter of 26 nm is formed on the entire surface of the substrate. Although the grain boundary is generated as described above, this is not problematic due to an averaging effect within the pixel. 
     Next, PS-r-PMMA and the SiO2 film  511  are etched by a dry etching technology. Moreover, Si is etched by a dry etching technology. At such a step, a cylindrical hole is formed in the SiO2 film  511 . Furthermore, the SiO2 film  511  is left by about 25 nm. 
     In other words, as illustrated at step S 51  in  FIG. 33 , the SiO2 film  511  having a thickness of 25 nm is deposited on the Si substrate  38 , and the cylindrical hole having a predetermined size is formed in the SiO2 film  511 . A predetermined size of the cylindrical hole may be made the same as the size of the cylindrical hole which is wanted to be formed in the Si substrate  38 , and may be, for example, 26 nm. 
     By adjusting a condition for dry etching the SiO2 film and Si, it is possible to make the hole diameter in the SiO2 film  511  26 nm. By forming in this manner, it is possible to form such that the space occupancy of the cylindrical hole corresponds to 0.384. Furthermore, the height (depth) of the cylinder is set to 25 nm (=thickness of the SiO2 film  511 ). 
     The Si substrate  38  subjected to the processes heretofore is prepared at step S 51 . As illustrated at step S 51  in  FIG. 33 , in a cross section, a portion which becomes the recess portion  37   a  (projected portion  37   b ) is not yet formed in the Si substrate  38  and the surface thereof is flat. The SiO2 film  511  is deposited on the Si substrate  38  having the flat upper surface and a cylindrical hole is formed in the SiO2 film  511 , the height of the cylindrical hole being 25 nm and the diameter of the hole being 26 nm. 
     Note that there may be a cylinder at a boundary of the R pixel, G pixel, or B pixel. 
     At step S 52 , positive type resist  521  for i-line is applied to the entire surface. The resist  521  is applied such that the cylinder hole is filled with the resist  521  and the height from the Si surface is 300 nm. 
     After the resist  521  is applied, exposure and development are performed so as to open only the area of the R pixel. Then, the etching is performed using the resist  521  and the SiO2 film  511  as a mask so that the depth of the recess portion  37   a  of the Si substrate  38  of the R pixel becomes 24 nm. A cross section at that time is illustrated at step S 52  in  FIG. 33 . 
     At step S 53  ( FIG. 34 ), the G pixel is etched. This is performed by the process similar to the etching performed on the R pixel at step S 52 . In other words, positive type resist for i line  531  is first applied to the entire surface. The resist  531  is applied such that the cylinder hole is filled with the resist  521  and the height from the Si surface is 300 nm. 
     After the resist  531  is applied, exposure and development are performed so as to open only the area of G pixel. Then, the etching is performed using the resist  531  and the SiO2 film  511  as a mask so that the depth of the recess portion  37   a  of the Si substrate  38  of the G pixel becomes 12 nm. A cross section at that time is illustrated at step S 53  in  FIG. 34 . 
     At steps heretofore, a cylindrical hole having a depth of 24 nm is formed in a portion corresponding to the R pixel of the Si substrate  38  and a cylindrical hole having a depth of 12 nm is formed in a portion corresponding to the G pixel of the Si substrate  38 . 
     At step S 54 , etching on the B pixel and further etching on the R pixel and the G pixel are performed. At this step, a cylindrical hole having a desired height is formed in each of the R pixel, the G pixel, and the B pixel. 
     That is, at step S 54 , using the SiO2 film  511  as a mask, etching to the depth of 42 nm is executed on the entire surface of the Si substrate  38 . After the etching, the SiO2 film  511  is removed. A cross section at that time is illustrated at step S 55  in  FIG. 34 . 
     Finally, the height H (depth) of the hole formed in the Si substrate  38  corresponding to the R pixel is 66 nm as illustrated at step S 55  in  FIG. 34 . Furthermore, the height H (depth) of the hole formed in the Si substrate  38  corresponding to the G pixel is 54 nm. Furthermore, the height H (depth) of the hole formed in the Si substrate  38  corresponding to the B pixel is 42 nm. 
     The height H of the hole is a value set as described above. For example, this is the value set under any one of the conditions C-1 to C-3. 
     In this manner, a process condition is herein adjusted so that the height H of the R pixel is 66 nm, the height H of the G pixel is 54 nm, and the height H of the B pixel is 42 nm. At such step, the height of the hole of each pixel may be changed, and the condition at each step described above, for example, the etching strength, time and the like are adjusted such that the desired hole height is realized. 
     In a case where the cylindrical hole (uneven structure) is formed in the Si substrate  38  in this manner, as illustrated at step S 55  in  FIG. 34 , the upper surface of the Si substrate  38  of the R pixel, the upper surface of the Si substrate  38  of the G pixel, and the upper surface of the Si substrate  38  of the B pixel are at the same height and there is no step between the pixels. 
     Unlike the solid-state imaging device  11  manufactured by the first manufacturing method, since there is no step at the boundary between the pixels, it is possible to suppress the generation of the stray light which might be generated due to the step. 
     Furthermore, in order to prevent double etching at the boundary between the pixels, in the exposure of the aperture of the pixel part, an area of the aperture is reduced from the pixel size by an expected overlay error. As a result, it is considered that there may be no significant effect even if the hole depth in the boundary area between the pixels becomes 42 nm. 
     In this manner, the process on the Si substrate  38  in which the cylindrical hole in which the height H of the R pixel is 66 nm, the height H of the G pixel is 54 nm, and the height H of the B pixel is 42 nm is formed may be performed as that in the fourth manufacturing method, in other words, as in the case described with reference to  FIG. 32 , so that the description thereof is herein omitted. 
     Note that, as illustrated in  FIG. 1 , in a case of manufacturing the solid-state imaging device  11  including the light-shielding film  34 , after the light-shielding film  34  is formed on the intermediate second layer  36 , the planarizing film  33  is formed so as to planarize, and thereafter the color filter  32  is formed. 
     Note that, here, a case where a process of first forming a cylindrical hole of 24 nm for the R pixel, then forming a cylindrical hole of 12 nm for the G pixel, and finally forming a cylindrical hole of 42 nm for the R pixel, the G pixel, and the B pixel is executed is described as an example. 
     That is, after the etching of 24 nm is performed on the R pixel, the etching of 42 nm is performed thereon, so that the etching of 64 nm is finally performed. Furthermore, after the etching of 12 nm is performed on the G pixel, the etching of 42 nm is performed thereon, so that the etching of 54 nm is finally performed. Furthermore, the etching of 42 nm is performed on the B pixel, and the etching of 42 nm is finally performed. 
     The order is not limited thereto, and the cylindrical hole having a desired height may be finally formed in another order. 
     For example, it is also possible that a process of first forming a cylindrical hole of 42 nm for the B pixel, then forming a cylindrical hole of 12 nm for the R pixel and G pixel, and finally forming a cylindrical hole of 12 nm for the R pixel is executed. 
     That is, after the etching of 42 nm is performed on the R pixel, the etching of 12 nm is performed thereon, and etching of 12 nm is further performed thereon, so that the etching of 64 nm is finally performed. Furthermore, after the etching of 42 nm is performed on the G pixel, the etching of 12 nm is performed thereon, so that the etching of 54 nm is finally performed. Furthermore, the etching of 42 nm is performed on the B pixel, and the etching of 42 nm is finally performed. The etching may also be performed in this order. 
     In this manner, by manufacturing the solid-state imaging device  11  so that the height H of the hole of each of the R pixel, G pixel, and B pixel becomes the optimized height H, the manufactured solid-state imaging device  11  may be, for example, the solid-state imaging device  11  having the characteristic as illustrated in FIG.  19 . 
     In other words, this may be made the solid-state imaging device  11  capable of significantly reducing the reflection light from the Si substrate  38  in all of the R pixel, the G pixel, and the B pixel. According to such solid-state imaging device  11 , it is possible to prevent the stray light (ghost flare) from being reflected in the image taken by the solid-state imaging device  11  and to make the solid-state imaging device  11  capable of improving the image quality. 
     &lt;Regarding Sixth Manufacturing Method of Solid-State Imaging Device Having Uneven Structure&gt; 
     Another manufacturing method (referred to as sixth manufacturing method) of the solid-state imaging device  11  is described. The sixth manufacturing method is basically the same as the fifth manufacturing method except that the number of steps is reduced. The sixth manufacturing method is described with reference to  FIGS. 35 and 36 . 
     At step S 61  ( FIG. 35 ), a substrate subjected to a predetermined process is prepared. The prepared substrate is the same as the substrate prepared at step S 51  ( FIG. 33 ) of the fifth manufacturing method. In other words, the substrate obtained by depositing the SiO2 film  511  on the Si substrate  38  to a thickness of 25 nm, and forming a cylindrical hole having a diameter of 26 nm. 
     At step S 62 , positive type resist  611  for i-line is applied to the entire surface. The resist  611  is applied such that the cylinder hole is filled with the resist  611  and the height from the Si surface is 300 nm. 
     After the resist  611  is applied, exposure and development are performed so as to open only the area of the R pixel and G pixel. Then, the etching is performed using the resist  611  and the SiO2 film  511  as a mask so that the depth of the recess portion  37   a  of the Si substrate  38  of the R pixel and G pixel becomes 12 nm. A cross section at that time is illustrated at step S 62  in  FIG. 35 . 
     At step S 63 , etching on the B pixel and further etching on the R pixel and the G pixel are performed. At this step, a cylindrical hole having a desired height is formed in each of the R pixel, the G pixel, and the B pixel. 
     In other words, at step  363 , using the SiO2 film  511  as a mask, etching to the depth of 42 nm is performed on the entire surface of the Si substrate  38 . After the etching, the SiO2 film  511  is removed. A cross section at that time is illustrated at step S 64  in  FIG. 36 . 
     Finally, the height H (depth) of the hole formed in the Si substrate  38  corresponding to the R pixel is made 54 nm as illustrated at step S 64  in  FIG. 36 . Furthermore, the height H (depth) of the hole formed in the Si substrate  38  corresponding to the G pixel is 54 nm. Furthermore, the height H (depth) of the hole formed in the Si substrate  38  corresponding to the B pixel is 42 nm. 
     In a case where the cylindrical hole (uneven structure) is formed in the Si substrate  38  in this manner, as illustrated at step S 64  in  FIG. 36 , the upper surface of the Si substrate  38  of the R pixel, the upper surface of the Si substrate  38  of the G pixel, and the tipper surface of the Si substrate  38  of the B pixel are at the same height and there is no step between the pixels. 
     Unlike the solid-state imaging device  11  manufactured by the first manufacturing method, since there is no step at the boundary between the pixels, it is possible to suppress the generation of the stray light which might be generated due to the step. 
     In this manner, the process on the Si substrate  38  in which the cylindrical hole in which the heights of the R pixel H is 54 nm, the height of the G pixel H is 54 nm, and the height of the B pixel H is 42 nm is formed may be performed as that in the fourth manufacturing method, in other words, as in the case described with reference to  FIG. 32 , so that the description thereof is herein omitted. 
     Note that, as illustrated in  FIG. 1 , in a case of manufacturing the solid-state imaging device  11  including the light-shielding film  34 , after the light-shielding film  34  is formed on the intermediate second layer  36 , the planarizing film  33  is formed so as to planarize, and thereafter the color filter  32  is formed. 
     According to the sixth manufacturing method, compared with the fifth manufacturing method, the number of steps, specifically, the number of times of etching and exposure may be reduced. Therefore, it is possible to obtain an effect that the steps at the time of manufacturing are simplified, and the cost required at the time of manufacturing is reduced. 
     However, as described above, the cylindrical hole which the height H of the R pixel is 54 nm, the height H of the G pixel is 54 nm, and the height H of the B pixel is 42 nm is formed. In other words, the height of the R pixel and the height of the G pixel are the same, and the height of the R pixel is not optimized. 
       FIG. 37  illustrates the reflection ratio on the upper surface of the uneven structure in the solid-state imaging device  11  having such a structure. The wavelength is plotted along the abscissa of the graph illustrated in  FIG. 37  and the light intensity reflection ratio is plotted along the ordinate. Furthermore, in  FIG. 37 , a line connecting lozenges (referred to as a graph BB) represents the light intensity reflection ratio in the B pixel, and a line connecting squares (referred to as a graph GR) represents the light intensity reflection ratio in the G pixel and R pixel. 
     With reference to the graph with the unevenness illustrated in  FIG. 18  and the graph BB illustrated in  FIG. 37 , it may be understood that, in a range of the effective wavelength region of the B pixel of 400 to 500 nm, the maximum reflection ratio decreases from 19% ( FIG. 18 ) to 3.7% ( FIG. 37 ). 
     Similarly, with reference to the graph with the unevenness illustrated in  FIG. 18  and the graph GR illustrated in  FIG. 37 , it may be understood that, in a range of the effective wavelength region of the G pixel of 500 to 600 nm, the maximum reflection ratio is substantially the same and is 1.0%. 
     Similarly, with reference to the graph with the unevenness illustrated in  FIG. 18  and the graph GR illustrated in  FIG. 19 , it may be understood that, in a range of the effective wavelength region of the R pixel of 600 to 700 nm, the maximum reflection ratio is substantially the same and is 3.4% ( FIG. 18 ). 
     For the R pixel, the hole height (depth) is not optimized, but the reflection ratio is as low as 3.4%, so that even in a case of manufacturing the solid-state imaging device  11  by the sixth manufacturing method, it is possible to obtain the solid-state imaging device  11  capable of reducing the reflection light from the Si substrate  38 . According to such solid-state imaging device  11 , it is possible to prevent the stray light (ghost flare) from being reflected in the image taken by the solid-state imaging device  11  and to make the solid-state imaging device  11  capable of improving the image quality. 
     Note that, although the example in which the height optimized for the G pixel is also applied to the R pixel is herein described, the height (depth) of the hole of the R pixel and the G pixel may be optimized to such a height that the maximum reflection ratios of the R pixel and the G pixel are low to the same degree. 
     Furthermore, although a case where the heights of the holes of the R pixel and the G pixel are the same is herein described as an example, it is also possible to manufacture the solid-state imaging device  11  so that the heights of the holes of the G pixel and the B pixel are the same. 
     Furthermore, a case where a process of first forming a cylindrical hole of 12 nm for the R pixel and G pixel, and then forming a cylindrical hole of 42 nm for the R pixel, G pixel, and B pixel as described with reference to  FIGS. 35 and 36  is executed is herein described as an example. 
     That is, the etching by 12 nm is performed and then the etching of 42 nm is performed on the R pixel and the G pixel, so that the etching by 54 nm is finally performed, and etching by 42 nm is performed on the B pixel, so that the etching by 42 nm is finally performed. 
     The order is not limited thereto, and the cylindrical hole having a desired height may be finally formed in another order. 
     For example, it is also possible that a process of first forming a cylindrical hole of 42 nm for the R pixel, G pixel, and B pixel, and then forming a cylindrical hole of 12 nm for the R pixel and G pixel is executed. 
     That is, the etching may be performed in order such that etching by 42 nm is performed and then the etching of 12 nm is performed on the R pixel and the G pixel, so that the etching by 54 nm is finally performed, and etching by 42 nm is performed on the B pixel, so that the etching by 42 nm is finally performed. 
     &lt;Regarding Seventh Manufacturing Method of Solid-State Imaging Device Having Uneven Structure&gt; 
     Another manufacturing method (referred to as seventh manufacturing method) of the solid-state imaging device  11  is described. In the following description of the seventh manufacturing method of the solid-state imaging device  11  also, a case of forming the pixel array unit of the Bayer array as illustrated in  FIG. 22  is described as an example as in the first manufacturing method. 
     With reference to  FIGS. 38 to 39 , the seventh manufacturing method of the solid-state imaging device having the uneven structure is described. In the drawing, a left view illustrates the R pixel, a center view illustrates the G pixel, and a right view illustrates the B pixel. 
     At step S 71  ( FIG. 38 ), a substrate as illustrated in  FIG. 38  is prepared. The manufacture of the substrate prepared at step S 51  is described. 
     First, when manufacturing a backside irradiation type imaging device, after a photodiode, a wiring layer and the like are formed, the substrate (Si substrate  38 ) reversed and joined to a support substrate. A surface of the substrate after the support substrate is joined is flat with Si. On the flat Si substrate  38 , an SiO2 film  711  is deposited to a thickness of 30 nm by chemical vapor deposition (CVD) or atomic layer deposition (ALD) technology. 
     A photosensitive resin  712  for nano imprinting is spin-coated on the deposited SiO2 film  711 . Alternatively, the photosensitive resin  712  for nano imprinting is intermittently dropped onto the deposited SiO2 film  711  by an ink jet method. 
     A template  713  having cylindrical projections obtained by reversing the hole array is pressed onto the deposited photosensitive resin  712  for nano imprinting. A size of the cylindrical projection of the template  713  is set as follows for each of the R pixel, the G pixel, and the B pixel. Space occupancy of the projection is also described below. 
     R pixel: diameter of 26.5 nm, height of 70 nm, and space occupancy of 0.394 
     G pixel: diameter of 26.0 nm, height of 64 nm, and space occupancy of 0.384 
     B pixel: diameter of 25.0 nm, height of 57 nm, and space occupancy of 0.360 
     The resin  712  spreads in a groove of the template  713  and between the template  713  and the SiO2 film  711  by capillary action. This situation is illustrated at step S 71  in  FIG. 38 . In such a state, ultraviolet (UV) light is transmitted from above the template  713  and is applied to the resin  712 . 
     By irradiation with the UV light, the resin  712  is cured. After the resin  712  is cured, the template  713  is peeled off. When the template  713  is peeled off, a shape illustrated at step S 72  in  FIG. 38  is formed in the resin  712 . 
     A thickness of the resin that enters between the template  713  and the Si substrate  38  (SiO2 film  711 ) is referred to as a residual layer thickness (RLT). The RLT is set to following values for the R pixel, G pixel, and B pixel. 
     R pixel: RLT of 10 nm 
     G pixel: RLT of 16 nm 
     B pixel: RLT of 23 nm 
     As illustrated at step S 72  in  FIG. 38 , the thickness (RLT) from the bottom of the cylindrical hole of the resin  712 R formed in the R pixel to the SiO2 film  711  is formed to be 10 nm. Furthermore, the thickness (RLT) from the bottom of the cylindrical hole of the resin  712 G formed in the G pixel to the SiO2 film  711  is formed to be 16 nm. Furthermore, the thickness (RLT) from the bottom of the cylindrical hole of the resin  712 B formed in the B pixel to the SiO2 film  711  is formed to be 23 nm. 
     As illustrated at step S 71  in  FIG. 38 , when the resin  712  is deposited by 80 nm and the template  713  is pressed against the resin  712  at a height of the projection of 70 nm, the RLT of 10 nm is finally formed. The RLT of 10 nm is the RLT in the R pixel as described above. 
     Similarly, as for the RLT of the G pixel, when the resin  712  is deposited by 80 nm and the template  713  is pressed against the resin  712  at a height of the projection of 64 nm, the RLT of 16 nm is finally formed. Moreover, similarly, when the resin  712  is deposited by 80 nm and the template  713  is pressed against the resin  712  at a height of the projection of 57 nm, the RLT of 23 nm is finally formed. 
     A process of etching the resin  712  and the SiO2 film  711  by a dry etching technology is performed on the substrate in a state in which such RLT is formed. By etching, the resin  712  is removed, and the cylindrical hole is formed in the SiO2 film  711 . 
     After the etching process, the bottom portion of the cylindrical hole formed in a SiO2 film  711 R of the R pixel has a thickness of 0 nm. Furthermore, the bottom portion of the cylindrical hole formed in a SiO2 film  711 G of the G pixel has a thickness of 6 nm. Furthermore, the bottom portion of the cylindrical hole formed in a SiO2 film  711 B of the B pixel has a thickness of 13 nm. The substrate on which the cylindrical hole is formed with such a thickness is illustrated at step S 73  in  FIG. 39 . 
     A process of etching the SiO2 film  711  and the Si substrate  38  is applied to the substrate in such a state. After the etching, the SiO2 film  711  remaining on the Si substrate  38  is removed. A cross section at that time is illustrated at step S 74  in  FIG. 39 . 
     As illustrated at step S 74  in  FIG. 39 , the etching condition is adjusted such that the height (depth) of the cylindrical hole is finally 67 nm for the R pixel, 54 nm for the G pixel, and 41 nm for the B pixel and the etching is performed. 
     The height H of the hole is a value set as described above. For example, this is the value set under any one of the conditions C-1 to C-3. 
     In this manner, the process condition is herein adjusted so that the height H of the R pixel is 67 nm, the height H of the G pixel is 54 nm, and the height H of the B pixel is 41 nm. At such step, the height of the hole of each pixel may be changed, and the condition at each step described above, for example, the etching strength, time and the like are adjusted such that the desired hole height is realized. 
     In a case where the cylindrical hole (uneven structure) is formed in the Si substrate  38  in this manner, as illustrated at step S 74  in  FIG. 39 , the upper surface of the Si substrate  38  of the R pixel, the upper surface of the Si substrate  38  of the G pixel, and the upper surface of the Si substrate  38  of the B pixel are at the same height and there is no step between the pixels. 
     Unlike the solid-state imaging device  11  manufactured by the first manufacturing method, since there is no step at the boundary between the pixels, it is possible to suppress the generation of the stray light which might be generated due to the step. 
     In this manner, the process on the Si substrate  38  in which the cylindrical hole is formed may be performed as that in the fourth manufacturing method, in other words, as in the case described with reference to  FIG. 32 , so that the description thereof is herein omitted. 
     Note that, as illustrated in  FIG. 1 , in a case of manufacturing the solid-state imaging device  11  including the light-shielding film  34 , after the light-shielding film  34  is formed on the intermediate second layer  36 , the planarizing film  33  is formed so as to planarize, and thereafter the color filter  32  is formed. 
     In this manner, by manufacturing the solid-state imaging device  11  so that the height H of the hole of each of the R pixel, G pixel, and B pixel becomes the optimized height H, the manufactured solid-state imaging device  11  may be, for example, the solid-state imaging device  11  having the characteristic as illustrated in  FIG. 20 . 
     According to the seventh manufacturing method, since the space occupancy may be adjusted by adjusting the projecting portion of the template  713 , the uneven structure may be formed with the space occupancy optimized for each pixel of the manufactured solid-state imaging device  11 . Therefore, it is possible to obtain the solid-state imaging device  11  having the characteristic (characteristic in a case where the space occupancy and the height are optimized) as illustrated in  FIG. 20 . 
     In other words, this may be made the solid-state imaging device  11  capable of significantly reducing the reflection light from the Si substrate  38  in all of the R pixel, the G pixel, and the B pixel. According to such solid-state imaging device  11 , it is possible to prevent the stray light (ghost flare) from being reflected in the image taken by the solid-state imaging device  11  and to make the solid-state imaging device  11  capable of improving the image quality. 
     &lt;Regarding Eighth Manufacturing Method of Solid-State Imaging Device Having Uneven Structure&gt; 
     Another manufacturing method (referred to as eighth manufacturing method) of the solid-state imaging device  11  is described. In the above-described manufacturing methods of the solid-state imaging device  11  (first to seventh manufacturing methods), a case of manufacturing such that the height of the cylindrical hole of each of the R pixel, the G pixel, and the B pixel (the height H of the projection  37   b ) is the optimal height is described as an example. 
     Moreover, the height may be adjusted according to the position of the pixel in the solid-state imaging device  11  (imaging device chip), for example, such that the height of the pixel located at the center of the pixel array unit and that of the pixel located in the periphery thereof are different. 
     There is a case where the light is obliquely incident on the photodiode in the pixels around the chip of the imaging device. Assuming that the incident angle is an angle i 1 , the height H is determined by converting the vacuum wavelength λ 0  as in following equation (24) and substituting a value into following equation (25). 
     
       
         
           
             
               
                 
                   [ 
                   
                     Equation 
                     ⁢ 
                     
                         
                     
                     ⁢ 
                     24 
                   
                   ] 
                 
               
               
                 
                     
                 
               
             
             
               
                 
                   
                     λ 
                     0 
                   
                   → 
                   
                     
                       λ 
                       0 
                     
                     ⁢ 
                     cos 
                     ⁢ 
                     
                         
                     
                     ⁢ 
                     
                       i 
                       1 
                     
                   
                 
               
               
                 
                   ( 
                   24 
                   ) 
                 
               
             
             
               
                 
                   [ 
                   
                     Equation 
                     ⁢ 
                     
                         
                     
                     ⁢ 
                     25 
                   
                   ] 
                 
               
               
                 
                     
                 
               
             
             
               
                 
                   H 
                   = 
                   
                     
                       λ 
                       ⁢ 
                       
                           
                       
                       ⁢ 
                       cos 
                       ⁢ 
                       
                           
                       
                       ⁢ 
                       
                         i 
                         1 
                       
                     
                     
                       4 
                       ⁢ 
                       
                         n 
                         eff 
                       
                     
                   
                 
               
               
                 
                   ( 
                   25 
                   ) 
                 
               
             
           
         
       
     
     Setting the height H in this manner makes it possible to further increase the antireflective effect over the entire imaging device, thereby realizing the solid-state imaging device  11  capable of preventing the stray light (ghost flare) from reflecting in the image taken by the solid-state imaging device  11  and improving the image quality. 
     &lt;Regarding Ninth Manufacturing Method of Solid-State Imaging Device Having Uneven Structure&gt; 
     Another manufacturing method (referred to as ninth manufacturing method) of the solid-state imaging device  11  is described. In the above-described manufacturing methods of the solid-state imaging device  11  (first to eighth manufacturing methods), the example in which the pitch P of the uneven structure is made small such that refraction of the light transmitted through the photo diode does not occur is described. 
     Although there is a possibility of diffraction on the transmission side (Si substrate  38  side), the pitch P of the uneven structure may be increased until diffraction does not occur on the reflection side (intermediate second layer  36  side). A condition that the pitch P should satisfy when manufacturing the solid-state imaging device  11  as described above is expressed by following equation (26). 
     
       
         
           
             
               
                 
                   [ 
                   
                     Equation 
                     ⁢ 
                     
                         
                     
                     ⁢ 
                     26 
                   
                   ] 
                 
               
               
                 
                     
                 
               
             
             
               
                 
                   P 
                   &lt; 
                   
                     
                       λ 
                       0 
                     
                     
                       
                         n 
                         1 
                       
                       ⁡ 
                       
                         ( 
                         
                           1 
                           + 
                           
                             sin 
                             ⁢ 
                             
                                 
                             
                             ⁢ 
                             
                               i 
                               1 
                             
                           
                         
                         ) 
                       
                     
                   
                 
               
               
                 
                   ( 
                   26 
                   ) 
                 
               
             
           
         
       
     
     If the pitch P satisfies equation (26), it is possible to manufacture the solid-state imaging device  11  in which diffraction does not occur on the reflection side. 
     Note that, although the diffraction does not occur on the reflection side in the solid-state imaging device  11 , there is a possibility that the diffraction occurs on the transmission side, so that, as illustrated in  FIG. 29 , for example, the light-shielding wall  321  may be formed between the pixels to configure such that an effect of the diffraction does not reach the adjacent pixel even if the diffraction occurs on the transmission side. 
     By forming the embedded light-shielding wall  321  between the pixels, it becomes possible to prevent the diffraction light from mixing into the photodiodes of the adjacent pixels by the light-shielding wall  321  even if the diffraction light is generated. 
     According to the ninth manufacturing method also, it is possible to prevent the stray light (ghost flare) from being reflected in the image taken by the solid-state imaging device  11  and to manufacture the solid-state imaging device  11  capable of improving the image quality. 
     &lt;Regarding Another Structure of Solid-State Imaging Device Having Uneven Structure&gt; 
     Another structure of the solid-state imaging device  11  is described.  FIG. 40  is a view illustrating another structure of the solid-state imaging device  11 . In the solid-state imaging device  11  illustrated in  FIG. 40 , the material embedded in the uneven structure portion is SiN or HfO2. 
     SiN or HfO2 is a transparent material for a wavelength of 400 to 700 nm, and has a refractive index or higher, which is higher than that of Al2O3. It is also possible to use such a material as a material embedded in the uneven structure portion. Here, it is continuously described on the assumption that. HfO2 is used. 
     The recess portion  37   a  of the Si substrate  38  of the solid-state imaging device  11  illustrated in  FIG. 40  is filled with HfO2, and a HfO2 film  811  is formed on the Si substrate  38 . Moreover, an Al2O3 film  812  is stacked on the HfO2 film  811 . Then, on the Al2O3 film  812 , the oxide film  35  of SiO2 is deposited. 
     In this manner, a plurality of layers may be formed between the Si substrate  38  and the oxide film  35 . According to the solid-state imaging device  11  illustrated in  FIG. 40 , a structure is such that layers of SiO2, Al2O3, HfO2, and Si are stacked in this order from the top (order in which light is incident), the structure in which the refractive index more gradually changes from SiO2 to Si. Therefore, the antireflective effect is increased over the wavelength of 400 to 700 nm. 
     The height H (depth) of the projected portion  37   b  in the uneven structure of the Si substrate  38  and the HfO2 film  811 , the thickness of the HfO2 film  811  (the thickness of the SiN film  811  in a case of using SiN as a material), the thickness of the Al2O3 film  812 , and the like may be determined according to the above-mentioned method and the theory of a multilayer reflective film. 
     &lt;Effect&gt; 
     As described above, it is possible to reduce the effect of the reflection light or diffraction light by using the solid-state imaging device  11  having the uneven structure. Furthermore, by setting the height (depth) of the uneven structure to the optimum height for each pixel (for each color), it is possible to further reduce the effect of the reflection light or diffraction light. That is, by setting the thickness of the intermediate first layer  37  to the optimum thickness for each pixel (for each color), it is possible to further reduce the effect of the reflection light or diffraction light. 
     In other words, by applying the present technology, it is possible to reduce the reflection on the upper surface of the photodiode even for a pixel having a different wavelength region to be sensed, and to prevent the reflection light from being reflected in another pixel as the stray light (ghost flare). 
     Furthermore, even in the pixels having the different wavelength regions to be sensed, it is possible to increase the sensitivity of the solid-state imaging device by increasing the ratio of light passing through the photodiode. 
     Furthermore, according to the present technology, it is possible to manufacture the solid-state imaging device capable of obtaining such an effect by the manufacturing method that may be realized at a lower cost than using the optical lithography technology used in the fine pattern formation. 
     Note that, in the above-described embodiment, the R pixel receiving red light, the G pixel receiving green light, and the B pixel receiving blue light are described as examples, but the present technology may also be applied to a pixel that receives light of another color. For example, the present technology is also applicable to a pixel that receives visible light (pixel so-called white pixel, clear pixel and the like), a pixel that receives light other than the visible light such as infrared light and the like. 
     &lt;Application Example to Electronic Device&gt; 
     The above-described solid-state imaging device may be applied to various electronic devices such as an imaging apparatus such as a digital still camera and a digital video camera, a mobile phone having an imaging function, or another device having the imaging function, for example. 
       FIG. 40  is a block diagram illustrating a configuration example of the imaging apparatus as the electronic device to which the present technology is applied. 
     An imaging apparatus  1001  illustrated in  FIG. 40  provided with an optical system  1002 , a shutter device  1003 , a solid-state imaging device  1004 , a driving circuit  1005 , a signal processing circuit  1006 , a monitor  1007 , and a memory  1008  may image a still image and a moving image. 
     The optical system  1002  including one or a plurality of lenses guides light from a subject (incident light) to the solid-state imaging device  1004  to form an image on a light-receiving surface of the solid-state imaging device  1004 . 
     The shutter device  1003  arranged between the optical system  1002  and the solid-state imaging device  1004  controls a light emission period to the solid-state imaging device  1004  and a light-shielding period according to control of the driving circuit  1005 . 
     The solid-state imaging device  1004  includes a package including the above-described solid-state imaging device. The solid-state imaging device  1004  stores a signal charge for a certain period according to the light the image of which is formed on the light-receiving surface through the optical system  1002  and the shutter device  1003 . The signal charge stored in the solid-state imaging device  1004  is transferred according to a driving signal (timing signal) supplied from the driving circuit  1005 . 
     The driving circuit  1005  outputs the driving signal to control transfer operation of the solid-state imaging device  1004  and shutter operation of the shutter device  1003  to drive the solid-state imaging device  1004  and the shutter device  1003 . 
     The signal processing circuit  1006  performs various types of signal processing on the signal charge output from the solid-state imaging device  1004 . The image (image data) obtained by the signal processing applied by the signal processing circuit  1006  is supplied to the monitor  1007  to be displayed or supplied to the memory  1008  to be stored recorded). 
     Also in the imaging apparatus  1001  configured as described above, by using the solid-state imaging device  11  in place of the above-described solid-state imaging device  1004 , reflection on the Si substrate  38  may be suppressed, sensitivity may be improved, and flare and ghost may be reduced. 
     In this specification, the term “system” is intended to mean an entire device including a plurality of devices. 
     Note that, the effect described in this specification is illustrative only; the effect is not limited thereto and there may also be another effect. 
     Note that, the embodiments of the present technology are not limited to the above-described embodiments and various modifications may be made without departing from the scope of the present technology. 
     Note that, the present technology may also have following configurations. 
     (1) 
     A solid-state imaging device includes: 
     a substrate including a photoelectric converting unit in a pixel unit; and 
     a reflection ratio adjusting layer provided on the substrate in an incident direction of incident light with respect to the substrate for adjusting reflection of the incident light on the substrate, 
     in which the reflection ratio adjusting layer includes 
     a first layer formed on the substrate and a second layer formed on the first layer, 
     the first layer has an uneven structure provided on the substrate, and a recess portion on the uneven structure is filled with a material having a lower refractive index than a refractive index of the substrate forming the second layer, and 
     a thickness of the first layer is made a thickness optimized for a wavelength of light to be received. 
     (2) 
     The solid-state imaging device according to (1) described above, 
     in which space occupancy of the first layer is space occupancy optimized for the wavelength of the light to be received. 
     (3) 
     The solid-state imaging device according to (1) or (2) described above, 
     in which the thickness of the first layer is set for each pixel and is made a thickness satisfying 
     
       
         
           
             
               
                 
                   [ 
                   
                     Equation 
                     ⁢ 
                     
                         
                     
                     ⁢ 
                     27 
                   
                   ] 
                 
               
               
                 
                     
                 
               
             
             
               
                 
                   H 
                   = 
                   
                     
                       λ 
                       0 
                     
                     
                       4 
                       ⁢ 
                       
                         n 
                         eff 
                       
                     
                   
                 
               
               
                 
                     
                 
               
             
           
         
       
     
     when the thickness is H, a refractive index of the first layer is neff, and the wavelength of the light to be received is λ. 
     (4) 
     The solid-state imaging device according to (3) described above, 
     in which an effective refractive index neff of the first layer satisfies
 
 n   eff =√{square root over ( n   1   n   2 )}  [Equation 28]
 
     when a refractive index of the second layer is n 1  and a refractive index of the substrate is n 2 . 
     (5) 
     The solid-state imaging device according to (1) or (2) described above, 
     in which the thickness of the first layer is set for each pixel and is made a thickness satisfying 
     
       
         
           
             
               
                 
                   [ 
                   
                     Equation 
                     ⁢ 
                     
                         
                     
                     ⁢ 
                     29 
                   
                   ] 
                 
               
               
                 
                     
                 
               
             
             
               
                 
                   h 
                   = 
                   
                     
                       
                         ∫ 
                         
                           λ 
                           min 
                         
                         
                           λ 
                           max 
                         
                       
                       ⁢ 
                       
                         
                           
                             
                               w 
                               ⁡ 
                               
                                 ( 
                                 λ 
                                 ) 
                               
                             
                             ⁢ 
                             λ 
                           
                           
                             
                               n 
                               eff 
                             
                             ⁡ 
                             
                               ( 
                               λ 
                               ) 
                             
                           
                         
                         ⁢ 
                         d 
                         ⁢ 
                         
                             
                         
                         ⁢ 
                         λ 
                       
                     
                     
                       4 
                       ⁢ 
                       
                         
                           ∫ 
                           
                             λ 
                             min 
                           
                           
                             λ 
                             max 
                           
                         
                         ⁢ 
                         
                           
                             w 
                             ⁡ 
                             
                               ( 
                               λ 
                               ) 
                             
                           
                           ⁢ 
                           d 
                           ⁢ 
                           
                               
                           
                           ⁢ 
                           λ 
                         
                       
                     
                   
                 
               
               
                 
                     
                 
               
             
           
         
       
     
     when the thickness is H, the wavelength of the light to be received is λ, a refractive index of the first layer is neff(λ), spectral sensitivity is w(λ), a maximum value of the wavelength of the light to be received is λmax, and a minimum value of the wavelength of the light to be received is λmin. 
     (6) 
     The solid-state imaging device according to (1) or (2) described above, 
     in which the thickness of the first layer is set for each pixel and is made a thickness satisfying 
     
       
         
           
             
               
                 
                   [ 
                   
                     Equation 
                     ⁢ 
                     
                         
                     
                     ⁢ 
                     30 
                   
                   ] 
                 
               
               
                 
                     
                 
               
             
             
               
                 
                   H 
                   = 
                   
                     
                       λ 
                       p 
                     
                     
                       4 
                       ⁢ 
                       
                         
                           n 
                           eff 
                         
                         ⁡ 
                         
                           ( 
                           
                             λ 
                             p 
                           
                           ) 
                         
                       
                     
                   
                 
               
               
                 
                     
                 
               
             
           
         
       
     
     when the thickness is H, a peak value of spectral sensitivity of the wavelength of the light to be received is λp, and the refractive index of the first layer is neff(λ). 
     (7) 
     The solid-state imaging device according to (1) or (2) described above, 
     in which the thickness of the first layer is set for each pixel and is made a thickness in a range satisfying 
     
       
         
           
             
               
                 
                   
                     
                       λ 
                       L 
                     
                     
                       4 
                       ⁢ 
                       
                         
                           n 
                           eff 
                         
                         ⁡ 
                         
                           ( 
                           
                             λ 
                             L 
                           
                           ) 
                         
                       
                     
                   
                   ≤ 
                   H 
                   ≤ 
                   
                     
                       λ 
                       U 
                     
                     
                       4 
                       ⁢ 
                       
                         
                           n 
                           eff 
                         
                         ⁡ 
                         
                           ( 
                           
                             λ 
                             U 
                           
                           ) 
                         
                       
                     
                   
                 
               
               
                 
                   [ 
                   
                     Equation 
                     ⁢ 
                     
                         
                     
                     ⁢ 
                     31 
                   
                   ] 
                 
               
             
           
         
       
     
     when the thickness is H, and thresholds of spectral sensitivity of the wavelength of the light to be received are λL and λU. 
     (8) 
     The solid-state imaging device according to any one of (1) to (7), 
     in which space occupancy of the first layer satisfies 
     
       
         
           
             
               
                 
                   f 
                   = 
                   
                     
                       
                         ∫ 
                         
                           λ 
                           
                             m 
                             ⁢ 
                             
                                 
                             
                             ⁢ 
                             i 
                             ⁢ 
                             
                                 
                             
                             ⁢ 
                             n 
                           
                         
                         
                           λ 
                           
                             ma 
                             ⁢ 
                             
                                 
                             
                             ⁢ 
                             x 
                           
                         
                       
                       ⁢ 
                       
                         
                           F 
                           ⁡ 
                           
                             ( 
                             λ 
                             ) 
                           
                         
                         ⁢ 
                         d 
                         ⁢ 
                         
                             
                         
                         ⁢ 
                         λ 
                       
                     
                     
                       
                         λ 
                         
                           ma 
                           ⁢ 
                           
                               
                           
                           ⁢ 
                           x 
                         
                       
                       - 
                       
                         λ 
                         
                           m 
                           ⁢ 
                           
                               
                           
                           ⁢ 
                           i 
                           ⁢ 
                           
                               
                           
                           ⁢ 
                           n 
                         
                       
                     
                   
                 
               
               
                 
                   [ 
                   
                     Equation 
                     ⁢ 
                     
                         
                     
                     ⁢ 
                     32 
                   
                   ] 
                 
               
             
           
         
       
     
     when the space occupancy is f, the wavelength of the light to be received is λ, a maximum value of the wavelength of the light to be received is λmax, a minimum value of the wavelength of the light to be received is λmin, and space occupancy at a predetermined wavelength is F(λ). 
     (9) 
     The solid-state imaging device according to any one of (1) to (7), 
     in which space occupancy of the first layer satisfies 
     
       
         
           
             
               
                 
                   f 
                   = 
                   
                     
                       
                         ∫ 
                         
                           λ 
                           
                             m 
                             ⁢ 
                             
                                 
                             
                             ⁢ 
                             i 
                             ⁢ 
                             
                                 
                             
                             ⁢ 
                             n 
                           
                         
                         
                           λ 
                           
                             m 
                             ⁢ 
                             
                                 
                             
                             ⁢ 
                             ax 
                           
                         
                       
                       ⁢ 
                       
                         
                           w 
                           ⁡ 
                           
                             ( 
                             λ 
                             ) 
                           
                         
                         ⁢ 
                         
                           F 
                           ⁡ 
                           
                             ( 
                             λ 
                             ) 
                           
                         
                         ⁢ 
                         d 
                         ⁢ 
                         
                             
                         
                         ⁢ 
                         λ 
                       
                     
                     
                       
                         ∫ 
                         
                           λ 
                           
                             m 
                             ⁢ 
                             
                                 
                             
                             ⁢ 
                             i 
                             ⁢ 
                             
                                 
                             
                             ⁢ 
                             n 
                           
                         
                         
                           λ 
                           
                             m 
                             ⁢ 
                             
                                 
                             
                             ⁢ 
                             ax 
                           
                         
                       
                       ⁢ 
                       
                         
                           w 
                           ⁡ 
                           
                             ( 
                             λ 
                             ) 
                           
                         
                         ⁢ 
                         d 
                         ⁢ 
                         
                             
                         
                         ⁢ 
                         λ 
                       
                     
                   
                 
               
               
                 
                   [ 
                   
                     Equation 
                     ⁢ 
                     
                         
                     
                     ⁢ 
                     33 
                   
                   ] 
                 
               
             
           
         
       
     
     when the space occupancy is f, the wavelength of the light to be received is λ, spectral sensitivity is w(λ), a maximum value of the wavelength of the light to be received is λmax, a minimum value of the wavelength of the light to be received is λmin, and space occupancy at a predetermined wavelength is F(λ). 
     (10) 
     The solid-state imaging device according to any one of (1) to (7) described above, 
     in which space occupancy of the first layer satisfies
 
 f=F (λ c )  [Equation 34]
 
     when the space occupancy is f, the wavelength of the light to be received is λ, a critical wavelength in image quality is λc, and space occupancy at a predetermined wavelength is F(λ). 
     (11) 
     The solid-state imaging device according to any one of (1) to (7) described above, 
     in which space occupancy of the first layer satisfies
 
Min[ F (λ)]≤ f ≤Max[ F (λ)]  [Equation 35]
 
     where 
     λmin≤λ≤λmax 
     when the space occupancy is f, the wavelength of the light to be received is λ, a maximum value of the wavelength of the light to be received is λmax, a minimum value of the wavelength of the light to be received is λmin, and space occupancy at a predetermined wavelength is F(λ). 
     (12) 
     The solid-state imaging device according to any one of (1) to (7) described above, 
     in which space occupancy of the first layer satisfies 
     
       
         
           
             
               
                 
                   f 
                   = 
                   
                     
                       
                         ∫ 
                         
                           λ 
                           
                             m 
                             ⁢ 
                             
                                 
                             
                             ⁢ 
                             i 
                             ⁢ 
                             
                                 
                             
                             ⁢ 
                             n 
                           
                         
                         
                           λ 
                           
                             m 
                             ⁢ 
                             
                                 
                             
                             ⁢ 
                             ax 
                           
                         
                       
                       ⁢ 
                       
                         
                           w 
                           ⁡ 
                           
                             ( 
                             λ 
                             ) 
                           
                         
                         ⁢ 
                         
                           F 
                           ⁡ 
                           
                             ( 
                             λ 
                             ) 
                           
                         
                         ⁢ 
                         d 
                         ⁢ 
                         
                             
                         
                         ⁢ 
                         λ 
                       
                     
                     
                       
                         ∫ 
                         
                           λ 
                           
                             m 
                             ⁢ 
                             
                                 
                             
                             ⁢ 
                             i 
                             ⁢ 
                             
                                 
                             
                             ⁢ 
                             n 
                           
                         
                         
                           λ 
                           
                             m 
                             ⁢ 
                             
                                 
                             
                             ⁢ 
                             ax 
                           
                         
                       
                       ⁢ 
                       
                         
                           w 
                           ⁡ 
                           
                             ( 
                             λ 
                             ) 
                           
                         
                         ⁢ 
                         d 
                         ⁢ 
                         
                             
                         
                         ⁢ 
                         λ 
                       
                     
                   
                 
               
               
                 
                   [ 
                   
                     Equation 
                     ⁢ 
                     
                         
                     
                     ⁢ 
                     36 
                   
                   ] 
                 
               
             
           
         
       
     
     when the space occupancy is f, the wavelength of the light to be received is λ, spectral sensitivity is w(λ), a maximum value of the wavelength of the light to be received is λmax, a minimum value of the wavelength of the light to be received is λmin, and space occupancy at predetermined wavelength is F(λ) for each pixel. 
     (13) 
     The solid-state imaging device according to any one of (1) to (7) described above, 
     in which space occupancy of the first layer satisfies
 
 f=F (λ p )  [Equation 37]
 
     when the space occupancy is f, the wavelength of the light to be received is λ, a peak value of spectral sensitivity of the wavelength of the light to be received is λp, and space occupancy at a predetermined wavelength is F(λ). 
     (14) 
     The solid-state imaging device according to any one of (1) to (7) described above, 
     in which space occupancy of the first layer satisfies
 
 F (λ L )≤ f≤F (λ U )  [Equation 38]
 
     when the space occupancy is f, the wavelength of the light to be received is λ, thresholds of spectral sensitivity of the wavelength of the light to be received are ΔL and λU, and space occupancy at a predetermined wavelength is F(λ). 
     (15) 
     The solid-state imaging device according to (1) described above, 
     in which an interval between projected portions of the first layer is made an interval satisfying 
     
       
         
           
             
               
                 
                   P 
                   &lt; 
                   
                     
                       λ 
                       0 
                     
                     
                       
                         n 
                         1 
                       
                       ⁡ 
                       
                         ( 
                         
                           1 
                           + 
                           
                             sin 
                             ⁢ 
                             
                                 
                             
                             ⁢ 
                             
                               i 
                               1 
                             
                           
                         
                         ) 
                       
                     
                   
                   ≤ 
                   
                     
                       λ 
                       0 
                     
                     
                       2 
                       ⁢ 
                       
                         n 
                         1 
                       
                     
                   
                 
               
               
                 
                   [ 
                   
                     Equation 
                     ⁢ 
                     
                         
                     
                     ⁢ 
                     39 
                   
                   ] 
                 
               
             
           
         
       
     
     when the interval is P, the wavelength of the light to be received is λ 0 , an incident angle is i 1 , and a refractive index of the second layer is n 1 . 
     (16) 
     The solid-state imaging device according to any one of (1) to (15), 
     in which an interval between projected portions of the first layer is made an interval satisfying 
     
       
         
           
             
               
                 
                   P 
                   &lt; 
                   
                     
                       λ 
                       0 
                     
                     
                       
                         n 
                         2 
                       
                       + 
                       
                         
                           n 
                           1 
                         
                         ⁢ 
                         sin 
                         ⁢ 
                         
                             
                         
                         ⁢ 
                         
                           i 
                           1 
                         
                       
                     
                   
                   ≤ 
                   
                     
                       λ 
                       0 
                     
                     
                       
                         n 
                         1 
                       
                       + 
                       
                         n 
                         
                           2 
                           ⁢ 
                           
                               
                           
                         
                       
                     
                   
                 
               
               
                 
                   [ 
                   
                     Equation 
                     ⁢ 
                     
                         
                     
                     ⁢ 
                     40 
                   
                   ] 
                 
               
             
           
         
       
     
     when the interval is P, the wavelength of the light to be received is λ 0 , an incident angle is i 1 , a refractive index of the second layer is n 1 , and a refractive index of the substrate is n 2 . 
     (17) 
     The solid-state imaging device according to (1) described above, 
     in which an uneven structure provided on the substrate is formed by etching using a self assembly. 
     (18) 
     A manufacturing method of manufacturing a solid-state imaging device provided with 
     a substrate including a photoelectric converting unit in a pixel unit, and 
     a reflection ratio adjusting layer provided on the substrate in an incident direction of incident light with respect to the substrate for adjusting reflection of the incident light on the substrate, the method including: 
     forming the reflection ratio adjusting layer including 
     a first layer formed on the substrate and a second layer formed on the first layer; 
     filling a recess portion on an uneven structure provided on the substrate included in the first layer with a material having a lower refractive index than a refractive index of the substrate forming the second layer; and 
     making a thickness of the first layer a thickness optimized for a wavelength of light to be received. 
     (19) 
     The manufacturing method according to (18) described above, 
     in which the uneven structure provided on the substrate is formed by etching using a self assembly. 
     (20) 
     The manufacturing method according to (18) or (19) described above, 
     in which the uneven structure is formed by etching using a gray tone mask having an aperture ratio capable of processing to the thickness optimized for the wavelength of the light to be received. 
     REFERENCE SIGNS LIST 
     
         
           11  Solid-state imaging device 
           31  Lens 
           32  Color filter 
           33  Planarizing film 
           34  Light-shielding film 
           35  Oxide film 
           36  Intermediate second layer 
           37  Intermediate first layer 
           38  Si substrate