SOLID-STATE IMAGING DEVICE AND ELECTRONIC EQUIPMENT

A solid-state imaging device capable of improving image quality and functionality is provided. Provided is a solid-state imaging device including a pixel region in which a plurality of pixels are two-dimensionally disposed, in which each of the pixels includes a photoelectric conversion unit and a concavo-convex portion, the photoelectric conversion unit photoelectrically converting incident light formed on a semiconductor substrate, and the concavo-convex portion being positioned above the photoelectric conversion unit and formed on a light receiving surface side of the semiconductor substrate, and the number of irregularities of a concavo-convex portion included in a pixel disposed in a central portion of the pixel region and the number of irregularities of a concavo-convex portion included in a pixel disposed in a peripheral portion of the pixel region are different from each other.

TECHNICAL FIELD

The present technology relates to a solid-state imaging device and electronic equipment.

BACKGROUND ART

In recent years, digital cameras have become increasingly popular, and the demand for solid-state imaging devices (image sensors), which are the core components of digital cameras, is increasing. Along with this, technological developments for achieving high image quality and high functionality in solid-state imaging devices are being actively performed. For example, technology related to photoelectric conversion devices in which a concavo-convex shape is formed in the thickness direction of a substrate to improve sensitivity characteristics has been proposed (see PTL 1).

CITATION LIST

Patent Literature

JP 2005-72097 A

SUMMARY

Technical Problem

However, in the technology proposed in PTL 1, there is a concern that it is not possible to achieve higher image quality and higher functionality.

Consequently, the present technology is contrived in view of such circumstances, and an object thereof is to provide a solid-state imaging device that can further improve image quality and functionality, and electronic equipment on which the solid-state imaging device is mounted.

Solution to Problem

As a result of ardent research to solve the above-mentioned object, the inventor has succeeded in further improving image quality and functionality of a solid-state imaging device, and has completed the present technology.

That is, in the present technology, as a first aspect, provided is a solid-state imaging device including a pixel region in which a plurality of pixels are two-dimensionally disposed, in which each of the pixels includes a photoelectric conversion unit and a concavo-convex portion, the photoelectric conversion unit photoelectrically converting incident light formed on a semiconductor substrate, and the concavo-convex portion being positioned above the photoelectric conversion unit and formed on a light receiving surface side of the semiconductor substrate, and the number of irregularities of a concavo-convex portion included in a pixel disposed in a central portion of the pixel region and the number of irregularities of a concavo-convex portion included in a pixel disposed in a peripheral portion of the pixel region are different from each other.

In the solid-state imaging device according to the first aspect of the present technology, the number of irregularities of the concavo-convex portion included in the pixel disposed in the central portion of the pixel region may be smaller than the number of irregularities of the concavo-convex portion included in the pixel disposed in the peripheral portion of the pixel region.

In the solid-state imaging device according to the first aspect of the present technology, the number of irregularities of the concavo-convex portion included in each pixel constituting the plurality of pixels may change from the pixel disposed in the central portion of the pixel region to the pixel disposed in the peripheral portion of the pixel region.

In the solid-state imaging device according to the first aspect of the present technology, the number of irregularities of the concavo-convex portion included in each pixel constituting the plurality of pixels may gradually increase from the pixel disposed in the central portion of the pixel region to the pixel disposed in the peripheral portion of the pixel region.

In the solid-state imaging device according to the first aspect of the present technology, a pitch of a convex portion constituting the concavo-convex portion included in the pixel disposed in the central portion of the pixel region and a pitch of a convex portion constituting the concavo-convex portion included in the pixel disposed in the peripheral portion of the pixel region may be different from each other.

In the solid-state imaging device according to the first aspect of the present technology, a pitch of a convex portion constituting the concavo-convex portion included in the pixel disposed in the central portion of the pixel region may be larger than a pitch of a convex portion constituting the concavo-convex portion included in the pixel disposed in the peripheral portion of the pixel region.

In the solid-state imaging device according to the first aspect of the present technology, a pitch of a convex portion constituting the concavo-convex portion included in the pixel disposed in the central portion of the pixel region may be larger than a pitch of a convex portion constituting the concavo-convex portion included in the pixel disposed in the peripheral portion of the pixel region, the concavo-convex portion included in the pixel disposed in the central portion of the pixel region may be provided in an entire inner surface of the pixel when the pixel is seen in plan view, and the concavo-convex portion included in the pixel disposed in the peripheral portion of the pixel region may be provided in an entire inner surface of the pixel when the pixel is seen in plan view.

In the solid-state imaging device according to the first aspect of the present technology, the concavo-convex portion included in the pixel disposed in the central portion of the pixel region may have a point-symmetrical shape with a center of the concavo-convex portion as a point of symmetry when seen in plan view and have a rectangular shape, and the concavo-convex portion included in the pixel disposed in the peripheral portion of the pixel region may have a point-symmetrical shape with a center of the concavo-convex portion as a point of symmetry when seen in plan view and have a rectangular shape.

In the solid-state imaging device according to the first aspect of the present technology, the concavo-convex portion included in the pixel disposed in the central portion of the pixel region may have a point-symmetrical shape with a center of the concavo-convex portion as a point of symmetry when seen in plan view and have a rectangular shape, and the concavo-convex portion included in the pixel disposed in the peripheral portion of the pixel region may have a point-symmetrical shape with a center of the concavo-convex portion as a point of symmetry when seen in plan view and have a polygonal shape.

In the solid-state imaging device according to the first aspect of the present technology, a concavo-convex portion included in each pixel constituting the plurality of pixels may be provided to cover a light converging region in which the incident light formed in the photoelectric conversion unit converges.

In the solid-state imaging device according to the first aspect of the present technology, a position at which the concavo-convex portion included in the pixel disposed in the central portion of the pixel region is provided in the pixel when the pixel is seen in plan view may be different from a position at which the concavo-convex portion included in the pixel disposed in the peripheral portion of the pixel region is provided in the pixel when the pixel is seen in plan view.

In the solid-state imaging device according to the first aspect of the present technology, the concavo-convex portion included in the pixel disposed in the central portion of the pixel region may be provided at least in a center portion in the pixel when the pixel is seen in plan view, and the concavo-convex portion included in the pixel disposed in the peripheral portion of the pixel region may be provided to extend at least from the center portion in the pixel toward a peripheral portion without reaching a boundary portion between the pixel and an adjacent pixel when the pixel is seen in plan view.

In the solid-state imaging device according to the first aspect of the present technology, the concavo-convex portion included in the pixel disposed in the central portion of the pixel region may be provided at least in a center portion in the pixel when the pixel is seen in plan view, and a concavo-convex portion included in a pixel disposed in a right peripheral portion in the pixel region when the pixel region is seen in plan view may be provided to extend at least from the center portion in the pixel toward a left peripheral portion without reaching a boundary portion between the pixel and an adjacent pixel when the pixel is seen in plan view.

In the solid-state imaging device according to the first aspect of the present technology, the concavo-convex portion included in the pixel disposed in the central portion of the pixel region may be provided at least in a center portion in the pixel when the pixel is seen in plan view, and a concavo-convex portion included in a pixel disposed in a left peripheral portion in the pixel region when the pixel region is seen in plan view may be provided to extend at least from the center portion in the pixel toward a right peripheral portion without reaching a boundary portion between the pixel and an adjacent pixel when the pixel is seen in plan view.

Further, in the present technology, as a second aspect, provided is a solid-state imaging device including a pixel region in which a plurality of pixels are two-dimensionally disposed, in which each of the pixels includes a photoelectric conversion unit and a concavo-convex portion, the photoelectric conversion unit photoelectrically converting incident light formed on a semiconductor substrate, and the concavo-convex portion being positioned above the photoelectric conversion unit and formed on a light receiving surface side of the semiconductor substrate, and a position at which the concavo-convex portion included in the pixel disposed in the central portion of the pixel region is provided in the pixel when the pixel is seen in plan view is different from a position at which the concavo-convex portion included in the pixel disposed in the peripheral portion of the pixel region is provided in the pixel when the pixel is seen in plan view.

In the solid-state imaging device according to the second aspect of the present technology, the concavo-convex portion included in the pixel disposed in the central portion of the pixel region may be provided at least in a center portion in the pixel when the pixel is seen in plan view, and the concavo-convex portion included in the pixel disposed in the peripheral portion of the pixel region may be provided to extend at least from the center portion in the pixel toward a peripheral portion without reaching a boundary portion between the pixel and an adjacent pixel when the pixel is seen in plan view.

In the solid-state imaging device according to the second aspect of the present technology, the concavo-convex portion included in the pixel disposed in the central portion of the pixel region may be provided at least in a center portion in the pixel when the pixel is seen in plan view, and a concavo-convex portion included in a pixel disposed in a right peripheral portion in the pixel region when the pixel region is seen in plan view may be provided to extend at least from the center portion in the pixel toward a left peripheral portion without reaching a boundary portion between the pixel and an adjacent pixel when the pixel is seen in plan view.

In the solid-state imaging device according to the second aspect of the present technology, the concavo-convex portion included in the pixel disposed in the central portion of the pixel region may be provided at least in a center portion in the pixel when the pixel is seen in plan view, and a concavo-convex portion included in a pixel disposed in a left peripheral portion in the pixel region when the pixel region is seen in plan view may be provided to extend at least from the center portion in the pixel toward a right peripheral portion without reaching a boundary portion between the pixel and an adjacent pixel when the pixel is seen in plan view.

Further, in the present technology, provided is electronic equipment on which the solid-state imaging device according to the first aspect of the present technology or the solid-state imaging device according to the second aspect of the present technology is mounted.

According to the present technology, it is possible to further improve image quality and functionality of a solid-state imaging device. Meanwhile, the effects described herein are not necessarily limiting, and any of the effects described in the present disclosure may be obtained.

DESCRIPTION OF EMBODIMENTS

Hereinafter, preferred embodiments for implementing the present technology will be described. The embodiments to be described below show an example of a representative embodiment of the present technology, and the scope of the present technology should not be narrowly construed based on this. Note that, in the drawings, unless otherwise specified, “up” means the upper direction or the upper side in the drawing, “down” means the lower direction or the lower side in the drawing, “left” means the left direction or the left side in the drawing, and “right” means the right direction or the right side in the drawing. Further, in the drawings, the same or equivalent elements or members are denoted by the same reference numerals and signs, and repeated description will be omitted.

The description will be made in the following order.

1. Outline of the present technology

10. Example of use of solid-state imaging device to which the present technology is applied

11. Example of application to endoscopic surgery system

12. Example of application to moving body

1. Outline of the Present Technology

First, an outline of the present technology will be described.

For example, in order to increase sensitivity characteristics of a single pixel (for example, one pixel), a convex-concave shape can be provided at an interface between a semiconductor substrate having a photoelectric conversion unit formed thereon and an insulating film. However, in an actual product, illuminance in a photoelectric conversion unit may differ in the plane of a chip (substrate) due to the influence of oblique incident light characteristics generated by an optical system such as a combination of lenses, and contrast unevenness may occur.

The present technology is contrived in view of the above-described circumstances. As a first aspect, the present technology can provide a solid-state imaging device including a pixel region in which a plurality of pixels are two-dimensionally disposed, in which each of the pixels includes a photoelectric conversion unit and a concavo-convex portion, the photoelectric conversion unit photoelectrically converting incident light formed on a semiconductor substrate, and the concavo-convex portion being positioned above the photoelectric conversion unit and formed on a light receiving surface side of the semiconductor substrate, and the number of irregularities of a concavo-convex portion included in a pixel disposed in a central portion of the pixel region and the number of irregularities of a concavo-convex portion included in a pixel disposed in a peripheral portion of the pixel region are different from each other. In addition, as a second aspect, the present technology can provide a solid-state imaging device including a pixel region in which a plurality of pixels are two-dimensionally disposed, in which each of the pixels includes a photoelectric conversion unit and a concavo-convex portion, the photoelectric conversion unit photoelectrically converting incident light formed on a semiconductor substrate, and the concavo-convex portion being positioned above the photoelectric conversion unit and formed on a light receiving surface side of the semiconductor substrate, and a position at which the concavo-convex portion included in the pixel disposed in the central portion of the pixel region is provided in the pixel when the pixel is seen in plan view is different from a position at which the concavo-convex portion included in the pixel disposed in the peripheral portion of the pixel region is provided in the pixel when the pixel is seen in plan view. According to the present technology, it is possible to manufacture a solid-state imaging device in which the uniformity of sensitivity in a chip surface or a substrate surface is increased. In addition, it is possible to reduce contrast unevenness reduction processing through gain adjustment of an analog circuit in a subsequent stage and signal processing by increasing the uniformity of sensitivity in the chip surface or the substrate surface.

Hereinafter, preferred embodiments for implementing the present technology will be described in detail with reference to the drawings. The embodiments to be described below show an example of a representative embodiment of the present technology, and the scope of the present technology should not be narrowly construed based on this.

A solid-state imaging device according to a first embodiment (Example 1 of a solid-state imaging device) of the present technology will be described usingFIGS.1and13.

First, description will be made usingFIG.1.FIG.1is a diagram illustrating a configuration example of the solid-state imaging device according to the first embodiment of the present technology. In more detail,FIG.1(a)is a plan view of a region1001acorresponding to four pixels included in a solid-state imaging device1001,FIG.1(b)is a plan view of a region1001bcorresponding to four pixels included in the solid-state imaging device1001,FIG.1(c)is a plan view of a region1001ccorresponding to four pixels included in the solid-state imaging device1001, andFIG.1(d)is a diagram illustrating contrast unevenness in a pixel region1001-G when seen in plan view from a light incident side.

As illustrated inFIG.1(a), in the region1001acorresponding to four pixels included in the solid-state imaging device1001, four pixels1001a-1to1001a-4are formed in a clockwise order, and a light shielding film5is formed between the pixels (pixel boundary).

The region1001acorresponding to four pixels is equivalent to a P1region which is a central portion in the pixel region1001-G illustrated inFIG.1(d).

The pixel1001a-1includes a concavo-convex portion11a-1, and the concavo-convex portion11a-1has a point-symmetrical shape with a pixel center t of the pixel1001a-1(seeFIG.1(a-1) to be described later; the same applies hereinafter) as a point of symmetry and has a rectangular shape. The pixel1001a-2includes a concavo-convex portion11a-2, and the concavo-convex portion11a-2has a point-symmetrical shape with a pixel center t of the pixel1001a-2as a point of symmetry and has a rectangular shape. The pixel1001a-3includes a concavo-convex portion11a-3, and the concavo-convex portion11a-3has a point-symmetrical shape with a pixel center t of the pixel1001a-3as a point of symmetry and has a rectangular shape. The pixel1001a-4includes a concavo-convex portion11a-4, and the concavo-convex portion11a-4has a point-symmetrical shape with a pixel center t of the pixel1001a-4as a point of symmetry and has a rectangular shape. Note that the pixel center t corresponds to the center of each of the concavo-convex portions11a-1to11a-4.

FIG.1(a-1) is an enlarged plan view of a concavo-convex portion11a-1illustrated inFIG.1(a), in which reference numerals11a-1A and11a-1C indicate a concave portion of a concavo-convex portion, and reference numeral11a-1B indicates a convex portion of the concavo-convex portion. One pitch is a length from the concave portion11a-1A to the concave portion11a-1C. In addition, a half pitch is a length from the concave portion11a-1A or the concave portion11a-1C to the concavo-convex portion11a-1B. Further, in the present specification, the range of an oblique line portion (the range indicated by reference numeral V1) in the concavo-convex portion11a-1is set as one unit of the concavo-convex portion, and represents the size of the concavo-convex portion when seen in plan view. Thus, the concavo-convex portion11a-1is constituted by four units. In addition, similarly, each of the concavo-convex portion11a-2, a concavo-convex portion11a-3, and a concavo-convex portion11a-4is four units. Each of a concavo-convex portion11b-1, a concavo-convex portion11b-2, a concavo-convex portion11b-3, and a concavo-convex portion11b-4to be described below is nine units inFIG.1(b), and each of a concavo-convex portion11c-1, a concavo-convex portion11c-2, a concavo-convex portion11c-3, and a concavo-convex portion11c-4is 16 units inFIG.1(c).

FIG.1(a-2) is a cross-sectional view taken along line A1-B1illustrated inFIG.1(a-1). As illustrated inFIG.1(a-2), a convex portion11a-1B of the concavo-convex portion11a-1has a triangular pyramid shape (triangle when seen in a cross-sectional view). Note that a concavo-convex portion17a-1can be manufactured by wet etching.

The concavo-convex portions11a-1to11a-4are formed in the center portion (a region surrounding the pixel center t) of each of the pixels1001a-1to1001a-4, and thus it is possible to prevent the reflection of vertically incident light and efficiently confine light to improve quantum efficiency. In addition, the concavo-convex portions11a-1to11a-4are not formed to the light shielding film5between the pixels, and a flat portion is formed on a peripheral edge of each of the four pixels1001a-1to1001a-4, and thus scattering may not occur due to the concavo-convex portion. In this case, there is no light leakage to the adjacent pixels, and thus color mixing can be prevented.

As illustrated inFIG.1(b), four pixels1001b-1to1001b-4are formed in a clockwise order in the region1001bcorresponding to four pixels included in the solid-state imaging device1001, and the light shielding film5is formed between the pixels (pixel boundary).

The region1001bcorresponding to four pixels is equivalent to a Q1region which is a right upper peripheral portion in the pixel region1001-G illustrated inFIG.1(d).

The pixel1001b-1includes a concavo-convex portion11b-1, and the concavo-convex portion11b-1has a point-symmetrical shape with the center of the concavo-convex portion11b-1as a point of symmetry and has a rectangular shape. The pixel1001b-2includes a concavo-convex portion11b-2, and the concavo-convex portion11b-2has a point-symmetrical shape with the center of the concavo-convex portion11b-2as a point of symmetry and has a rectangular shape. The pixel1001b-3includes a concavo-convex portion11b-3, and the concavo-convex portion11b-3has a point-symmetrical shape with the center of the concavo-convex portion11b-3as a point of symmetry and has a rectangular shape. The pixel1001b-4includes a concavo-convex portion11b-4, and the concavo-convex portion11b-4has a point-symmetrical shape with the center of the concavo-convex portion11b-4as a point of symmetry and has a rectangular shape. In addition, the number of irregularities of the concavo-convex portions11b-1to11b-4is larger than the number of irregularities of the concavo-convex portions11a-1to11a-4. By increasing the number of irregularities of the concavo-convex portions11b-1to11b-4, it is possible to increase sensitivity by more effectively preventing the reflection of right oblique light incident in the Q1region.

Each of the concavo-convex portions11b-1to11b-4is mainly formed in a left lower portion of the pixel (a left upper portion of the pixel may also be used) with respect to the pixel center t of each of the pixels1001b-1to1001b-4, and thus it is possible to prevent the reflection of right oblique incident light and efficiently confine light to improve the quantum efficiency. In a case where the concavo-convex portion is mainly formed in the right lower portion (or right upper portion) of the pixel, it is possible to prevent the reflection of left oblique incident light and efficiently confine light to improve quantum efficiency. In addition, the concavo-convex portions11b-1to11b-4are not formed to the light shielding film5between the pixels, and a flat portion is formed on a peripheral edge of each of the four pixels1001b-1to1001b-4, and thus scattering may not occur due to the concavo-convex portion. In this case, there is no light leakage to the adjacent pixels, and thus color mixing can be prevented.

As illustrated inFIG.1(c), four pixels1001c-1to1001c-4are formed in a clockwise order in the region1001ccorresponding to four pixels included in the solid-state imaging device1001, and the light shielding film5is formed between the pixels (pixel boundary).

The region1001ccorresponding to four pixels is equivalent to an R1region which is a right upper peripheral edge (the vicinity of a right upper vertex portion in the pixel region1001-G) of the right upper peripheral portion in the pixel region1001-G illustrated inFIG.1(d).

The pixel1001c-1includes a concavo-convex portion11c-1, and the concavo-convex portion11c-1has a point-symmetrical shape with the center of the concavo-convex portion11c-1as a point of symmetry and has a rectangular shape. The pixel1001c-2includes a concavo-convex portion11c-2, and the concavo-convex portion11c-2has a point-symmetrical shape with the center of the concavo-convex portion11c-2as a point of symmetry and has a rectangular shape. The pixel1001c-3includes a concavo-convex portion11c-3, and the concavo-convex portion11c-3has a point-symmetrical shape with the center of the concavo-convex portion11c-3as a point of symmetry and has a rectangular shape. The pixel1001c-4includes a concavo-convex portion11c-4, and the concavo-convex portion11c-4has a point-symmetrical shape with the center of the concavo-convex portion11c-4as a point of symmetry and has a rectangular shape. In addition, the number of irregularities of the concavo-convex portions11c-1to11c-4is larger than the number of irregularities of the concavo-convex portions11b-1to11b-4. By increasing the number of irregularities of the concavo-convex portions11c-1to11c-4, it is possible to increase sensitivity by more effectively preventing the reflection of right oblique light incident in the R1region.

Each of the concavo-convex portions11c-1to11c-4is mainly formed in a left lower portion of the pixel (a left upper portion of the pixel may also be used) with respect to the pixel center t of each of the pixels1001c-1to1001c-4, and thus it is possible to prevent the reflection of right oblique incident light and efficiently confine light to improve the quantum efficiency. In a case where the concavo-convex portion is mainly formed in the right lower portion (or right upper portion) of the pixel, it is possible to prevent the reflection of left oblique incident light and efficiently confine light to improve quantum efficiency. In addition, the concavo-convex portions11c-1to11c-4are not formed to the light shielding film5between the pixels, and a flat portion is formed on a peripheral edge of each of the four pixels1001c-1to1001c-4, and thus scattering may not occur due to the concavo-convex portion. In this case, there is no light leakage to the adjacent pixels, and thus color mixing can be prevented.

As described above, the number of irregularities of the concavo-convex portion increases from the P1region (the center portion of the pixel region) to the Q1region and the R1region, and it is possible to achieve the uniformity of sensitivity in the chip (in the substrate). That is, it is possible to improve contrast unevenness illustrated inFIG.1(d)by the solid-state imaging device according to the first embodiment (Example 1 of a solid-state imaging device) of the present technology.

Next, description will be made usingFIG.13.FIG.13is a diagram illustrating a configuration example of a solid-state imaging device according to the first embodiment of the present technology, and more specifically, is a cross-sectional view of a pixel2e(two pixels are illustrated in the drawing) of a solid-state imaging device1e.Note that a configuration example of the solid-state imaging device1ecan be applied to solid-state imaging devices of second to seventh embodiments according to the present technology to be described later, unless there is no particular technical contradiction.

The solid-state imaging device1eincludes a semiconductor substrate12e,a multilayer wiring layer21eformed on the surface side thereof (the lower side in the drawing), and a support substrate22e.

The semiconductor substrate12eis formed of, for example, silicon (Si), and is formed to have a thickness of, for example, 1 to 6 μm. In the semiconductor substrate12e,for example, an N-type (second conductive type) semiconductor region42eis formed for each pixel2ein a P-type (first conductive type) semiconductor region41e,and thus a photodiode PD is formed in pixel units. The P-type semiconductor region41efacing both the front and back surfaces of the semiconductor substrate12ealso serves as a hole charge storage region for suppressing a dark current.

Note that the P-type semiconductor region41eis deeply dug as illustrated inFIG.13at a pixel boundary of each pixel2ebetween the N-type semiconductor regions42ein order to form an inter-pixel light shielding portion47e.The inter-pixel light shielding portion47ehas an effect of reflecting incident light scattered by a concavo-convex portion48e(antireflection portion) and confining the incident light in the photoelectric conversion unit (photodiode (PD)).

An interface (an interface on a light receiving surface) of the P-type semiconductor region41eabove an N-type semiconductor region42eserving as a charge storage region constitutes an antireflection portion48ethat prevents the reflection of incident light by a so-called moth-eye structure in which minute concavo-convex portions (concavo-convex structures) are formed. That is, the antireflection portion (concavo-convex portion)48eincludes a convex portion48e-1and a concave portion48e-2. In the antireflection portion48e,a pitch of a convex portion of a triangular pyramid shape (triangle when seen in a cross-sectional view) which is equivalent to the cycle of irregularities is set to be, for example, in the range of 40 nm to 200 nm.

The multilayer wiring layer21eincludes a plurality of wiring layers43eand an interlayer insulating film44e.In addition, a plurality of pixel transistors Tr that perform read-out of charge accumulated in the photodiode PD, and the like are also formed in the multilayer wiring layer21e(at an interface between the multilayer wiring layer21eand the semiconductor substrate12e).

A pinning layer45eis formed on the back surface side of the semiconductor substrate12eso as to cover the upper surface of the P-type semiconductor region41e.The pinning layer45eis formed using a high dielectric having a negative fixed charge so that a positive charge (hole) storage region is formed at an interface with the semiconductor substrate12eand the generation of a dark current is suppressed. When the pinning layer45eis formed to have a negative fixed charge, an electric field is applied to the interface with the semiconductor substrate12eby the negative fixed charge, and thus a hole charge storage region is formed.

The pinning layer45eis formed using, for example, hafnium oxide (HfO2). In addition, the pinning layer45eis formed using zirconium dioxide (ZrO2), tantalum pentoxide (Ta2O5), or the like.

A transparent insulating film46eis embedded in a dug portion of the P-type semiconductor region41eand is formed on the entire back surface side of the upper portion of the pinning layer45eof the semiconductor substrate12e.The dug portion of the P-type semiconductor region41ehaving the transparent insulating film46eembedded therein constitutes the inter-pixel light shielding portion47ethat prevents leakage of incident light (for example, incident light scattered by the antireflection portion48) from the adjacent pixel2e.In addition, a flat portion48e-3constituted by the pinning layer45eis formed between the inter-pixel light shielding portion47eand the antireflection portion48e,light leakage to the adjacent pixels is less likely to occur by forming the flat portion48e-3, and thus color mixing can be further prevented.

The transparent insulating film46eis a material that transmits light, has an insulating property, and has a refractive index n1smaller than a refractive index n2of the semiconductor region41eand the semiconductor region42e(n1<n2). As a material of the transparent insulating film46e,silicon oxide (SiO2), silicon nitride (SiN), silicon oxynitride (SiON), hafnium oxide (HfO2), aluminum oxide (Al2O3), zirconium oxide (ZrO2), tantalum oxide (Ta2O5), titanium oxide (TiO2), lanthanum oxide (La2O3), placeodim oxide (Pr2O3), cerium oxide (CeO2), neoclim oxide (Nd2O3), promethium oxide (Pm2O3), samalium oxide (Sm2O3), europium oxide (Eu2O3), gadolinium oxide (Gd2O3), terbium oxide (Tb2O3), dysprosium oxide (Dy2O3), holmium oxide (Ho2O3), thulium oxide (Tm2O3), ytterbium oxide (Yb2O3), lutetium oxide (Lu2O3), yttrium oxide (Y2O3), a resin, and the like can be used alone or in combination.

Note that an antireflection film may be laminated on the upper side of the pinning layer45ebefore the transparent insulating film46eis formed. As a material of the antireflection film, silicon nitride (SiN), hafnium oxide (HfO2), aluminum oxide (Al2O3), zirconium oxide (ZrO2), tantalum oxide (Ta2Ta5), titanium oxide (TiO2), lanthanum oxide (La2O3), praseodymium oxide (Pr2O3), cerium oxide (CeO2), neodymium oxide (Nd2O3), promethium oxide (Pm2O3), samalium oxide (Sm2O3), europium oxide (Eu2O3), gadolinium oxide (Gd2O3), terbium oxide (Tb2O3), dysprosium oxide (Dy2O3), holmium oxide (Ho2O3), thulium oxide (Tm2O3), ytterbium oxide (Yb2O3), lutetium oxide (Lu2O3), yttrium oxide (Y2O3), and the like can be used.

The antireflection film may be formed on only the upper surface of the antireflection portion48eof the moth-eye structure, or may be formed on both the upper surface of the antireflection portion48eand the side surface of the inter-pixel light shielding portion47e,similar to the pinning layer45e.

A light shielding film49eis formed in a region of a pixel boundary on the transparent insulating film46e.As a material of the light shielding film49e,a material that shields light may be used, and for example, tungsten (W), aluminum (Al), copper (Cu), and the like can be used.

A flattened film50eis formed on the entire upper surface side of the transparent insulating film46eincluding the light shielding film49e.As a material of the flattened film50e,an organic material such as a resin can be used.

A color filter layers51eof red, green, or blue is formed for each pixel above the flattened film50e.The color filter layer51eis formed by rotationally applying a photosensitive resin containing a dye such as a pigment or a dye. Red, green, and blue colors are disposed by, for example, a Bayer arrangement, but may be disposed by other arrangement methods. In the example ofFIG.13, the color filter layer51eof Blue (B) is formed in the pixel2eon the right side, and the color filter layer51eof Green (G) is formed in the pixel2eon the left side. An on-chip lens52eis formed for each pixel2eabove the color filter layer51e.The on-chip lens52eis formed of a resin-based material such as a styrene-based resin, an acrylic-based resin, a styrene-acrylic copolymer resin, or a siloxane-based resin. Incident light converges on the on-chip lens52e,and the converged light is efficiently incident on the photocliode PD through the color filter layer51e.

A method of manufacturing the concavo-convex portion48ewill be described.

A photoresist is applied to the upper surface of the semiconductor substrate12eon the back surface side, and the photoresist is patterned by lithography technology so that a concave portion of the moth-eye structure of the antireflection portion (concavo-convex portion)48eis opened.

By performing wet etching processing on the semiconductor substrate12eon the basis of the patterned photoresist, the concave portion of the moth-eye structure of the antireflection portion48eis formed, and then the photoresist is removed. Note that, in a case where a convex portion has a spindle shape, the moth-eye structure of the antireflection portion48ecan be formed by dry etching processing, and in a case where a convex portion has a triangular pyramid shape as illustrated inFIG.13, the moth-eye structure can be formed by wet etching processing as described above.

Next, the pinning layer (metal oxide film)45eis formed on the entire surface (back surface) of the semiconductor substrate12eby, for example, a chemical vapor deposition (CVD) method, the semiconductor substrate12ehaving the antireflection portion48eof the moth-eye structure and a trench structure47eformed therein.

In addition, the insulating film46eis formed on the upper surface of the pinning layer (metal oxide film)45eusing a film formation method having a high embedding property such as a CVD method.

The above-described contents of the solid-state imaging device according to the first embodiment (Example 1 of a solid-state imaging device) of the present technology can be applied to solid-state imaging devices according to second to seventh embodiments of the present technology to be described later, unless there is no particular technical contradiction.

A solid-state imaging device according to a second embodiment (Example 2 of a solid-state imaging device) of the present technology will be described usingFIG.2.FIG.2is a diagram illustrating a configuration example of the solid-state imaging device according to the second embodiment of the present technology. In more detail,FIG.2(a)is a plan view of a region1002acorresponding to four pixels included in a solid-state imaging device1002,FIG.2(b)is a plan view of a region1002bcorresponding to four pixels included in the solid-state imaging device1002,FIG.2(c)is a plan view of a region1002ccorresponding to four pixels included in the solid-state imaging device1002, andFIG.2(d)is a diagram illustrating contrast unevenness in a pixel region1002-G when seen in plan view from a light incident side.

As illustrated inFIG.2(a), four pixels1002a-1to1002a-4are formed in a clockwise order in the region1002acorresponding to four pixels included in the solid-state imaging device1002, and a light shielding film5is formed between the pixels (pixel boundary).

The region1002acorresponding to four pixels is equivalent to a P2region which is a central portion of the pixel region1002-G illustrated inFIG.2(d).

The pixel1002a-1includes a concavo-convex portion12a-1, and the concavo-convex portion12a-1has a point-symmetrical shape with a pixel center t of the pixel1002a-1as a point of symmetry and has a rectangular shape. The pixel1002a-2includes a concavo-convex portion12a-2, and the concavo-convex portion12a-2has a point-symmetrical shape with a pixel center t of the pixel1002a-2as a point of symmetry and has a rectangular shape. The pixel1002a-3includes a concavo-convex portion12a-3, and the concavo-convex portion12a-3has a point-symmetrical shape with a pixel center t of the pixel1002a-3as a point of symmetry and has a rectangular shape. The pixel1002a-4includes a concavo-convex portion12a-4, and the concavo-convex portion12a-4has a point-symmetrical shape with a pixel center t of the pixel1002a-4as a point of symmetry and has a rectangular shape. The concavo-convex portions12a-1to12a-4are formed in all pixels of each of the four pixels1002a-1to1002a-4. Note that the pixel center t corresponds to the center of each of the concavo-convex portions12a-1to12a-4.

As illustrated inFIG.2(b), four pixels1002b-1to1002b-4are formed in a clockwise order in the region1002bcorresponding to four pixels included in the solid-state imaging device1002, and the light shielding film5is formed between the pixels (pixel boundary).

The region1002bcorresponding to four pixels is equivalent to a Q2region which is a right upper peripheral portion in the pixel region1002-G illustrated inFIG.2(d).

The pixel1002b-1includes a concavo-convex portion12b-1, and the concavo-convex portion12b-1has a point-symmetrical shape with a pixel center t of the pixel1002b-1as a point of symmetry and has a rectangular shape. The pixel1002b-2includes a concavo-convex portion12b-2, and the concavo-convex portion12b-2has a point-symmetrical shape with a pixel center t of the pixel1002b-2as a point of symmetry and has a rectangular shape. The pixel1002b-3includes a concavo-convex portion12b-3, and the concavo-convex portion12b-3has a point-symmetrical shape with a pixel center t of the pixel1002b-3as a point of symmetry and has a rectangular shape. The pixel1002b-4includes a concavo-convex portion12b-4, and the concavo-convex portion12b-4has a point-symmetrical shape with a pixel center t of the pixel1002b-4as a point of symmetry and has a rectangular shape. The concavo-convex portions12b-1to12b-4are formed in all pixels of each of the four pixels1002b-1to1002b-4. Note that the pixel center t corresponds to the center of each of the concavo-convex portions12b-1to12b-4. As illustrated inFIGS.2(a) and2(b), a pitch (d2b) of each of the concavo-convex portions12b-1to12b-4is smaller than a pitch (d2a) of each of the concavo-convex portions12a-1to12a-4, and the number of pitches (d2b) is larger than the number of pitches (d2a). By shortening the pitch of each of the concavo-convex portions12b-1to12b-4and increasing the number of pitches, it is possible to increase sensitivity by more effectively preventing the reflection of right oblique light incident in the Q2region.

As illustrated inFIG.2(c), four pixels1002c-1to1002c-4are formed in a clockwise order in the region1002ccorresponding to four pixels included in the solid-state imaging device1002, and the light shielding film5is formed between the pixels (pixel boundary).

The region1002ccorresponding to four pixels is equivalent to an R2region which is a right upper peripheral edge (the vicinity of a right upper vertex portion in the pixel region1002-G) of the right upper peripheral portion in the pixel region1002-G illustrated inFIG.2(d).

The pixel1002c-1includes a concavo-convex portion12c-1, and the concavo-convex portion12c-1has a point-symmetrical shape with a pixel center t of the pixel1002c-1as a point of symmetry and has a rectangular shape. The pixel1002c-2includes a concavo-convex portion12c-2, and the concavo-convex portion12c-2has a point-symmetrical shape with a pixel center t of the pixel1002c-2as a point of symmetry and has a rectangular shape. The pixel1002c-3includes a concavo-convex portion12c-3, and the concavo-convex portion12c-3has a point-symmetrical shape with a pixel center t of the pixel1002c-3as a point of symmetry and has a rectangular shape. The pixel1002c-4includes a concavo-convex portion12c-4, and the concavo-convex portion12c-4has a point-symmetrical shape with a pixel center t of the pixel1002c-4as a point of symmetry and has a rectangular shape. The concavo-convex portions12c-1to12c-4are formed in all pixels of each of the four pixels1002c-1to1002c-4. Note that the pixel center t corresponds to the center of each of the concavo-convex portions12c-1to12c-4. As illustrated inFIGS.2(b) and2(c), a pitch (d2c) of each of the concavo-convex portions12c-1to12c-4is smaller than a pitch (d2b) of each of the concavo-convex portions12b-1to12b-4, and the number of pitches (d2c) is larger than the number of pitches (d2b). By shortening the pitch of each of the concavo-convex portions12c-1to12c-4and increasing the number of pitches, it is possible to increase sensitivity by more effectively preventing the reflection of right oblique light incident in the R2region.

As described above, the number of pitches of the concavo-convex portion increases from the P2region (the center portion of the pixel region) to the Q2region and the R2region (the right peripheral portion in the pixel region), and it is possible to achieve the uniformity of sensitivity in the chip (in the substrate). That is, it is possible to improve contrast unevenness illustrated inFIG.2(d)by the solid-state imaging device according to the second embodiment (Example 2 of a solid-state imaging device) of the present technology.

The above-described contents of the solid-state imaging device according to the second embodiment (Example 2 of a solid-state imaging device) of the present technology can be applied to the above-described solid-state imaging device according to the first embodiment of the present technology and solid-state imaging devices to be described later according to third to seventh embodiments of the present technology, unless there is no particular technical contradiction.

A solid-state imaging device according to a third embodiment (Example 3 of a solid-state imaging device) of the present technology will be described usingFIGS.3to5.FIG.3is a diagram illustrating a configuration example of a solid-state imaging device according to the third embodiment of the present technology. In more detail,FIG.3(a)is a plan view of a region1003acorresponding to four pixels included in a solid-state imaging device1003, andFIG.3(b)is a diagram illustrating contrast unevenness in a pixel region1003-G.FIG.4is a diagram illustrating a configuration example of the solid-state imaging device according to the third embodiment of the present technology. In more detail,FIG.4(a)is a plan view of a region1004acorresponding to four pixels included in the solid-state imaging device1003,FIG.4(b)is a plan view of a region1004bcorresponding to four pixels included in the solid-state imaging device1003,FIG.4(c)is a plan view of a region1004ccorresponding to four pixels included in the solid-state imaging device1003, andFIG.4(d)is a diagram illustrating contrast unevenness in a pixel region1003-G.FIG.5is a diagram illustrating a configuration example of the solid-state imaging device according to the third embodiment of the present technology. In more detail,FIG.5(a)is a plan view of a region1005acorresponding to four pixels included in the solid-state imaging device1003,FIG.5(b)is a plan view of a region1005bcorresponding to four pixels included in the solid-state imaging device1003,FIG.5(c)is a plan view of a region1005ccorresponding to four pixels included in the solid-state imaging device1003, andFIG.5(d)is a diagram illustrating contrast unevenness in the pixel region1003-G.

As illustrated inFIG.3(a), in the region1003acorresponding to four pixels included in the solid-state imaging device1003, four pixels1003a-1to1003a-4are formed in a clockwise order, and a light shielding film5is formed between the pixels (pixel boundary).

The region1003acorresponding to four pixels is equivalent to a P3region which is a central portion in the pixel region1003-G illustrated inFIG.3(b).

The pixel1003a-1includes a concavo-convex portion13a-1, and the concavo-convex portion13a-1has a point-symmetrical shape with a pixel center t of the pixel1003a-1as a point of symmetry and has a rectangular shape. The pixel1003a-2includes a concavo-convex portion13a-2, and the concavo-convex portion13a-2has a point-symmetrical shape with a pixel center t of the pixel1003a-2as a point of symmetry and has a rectangular shape. The pixel1003a-3includes a concavo-convex portion13a-3, and the concavo-convex portion13a-3has a point-symmetrical shape with a pixel center t of the pixel1003a-3as a point of symmetry and has a rectangular shape. The pixel1003a-4includes a concavo-convex portion13a-4, and the concavo-convex portion13a-4has a point-symmetrical shape with a pixel center t of the pixel1003a-4as a point of symmetry and has a rectangular shape. Note that the pixel center t corresponds to the centers of the concavo-convex portions13a-1to13a-4.

The concavo-convex portions13a-1to13a-4are formed in center portions (regions surrounding the pixel centers t) of the respective pixels1003a-1to1003a-4, and thus it is possible to prevent the reflection of vertically incident light and efficiently confine vertically incident light to improve quantum efficiency. In addition, the concavo-convex portions13a-1to13a-4are not formed to the light shielding film5between the pixels, and a flat portion is formed on a peripheral edge of each of the four pixels1003a-1to1003a-4, and thus scattering may not occur due to the concavo-convex portion. In this case, there is no light leakage to the adjacent pixels, and thus color mixing can be prevented.

As illustrated inFIG.4(a), four pixels1004a-1to1004a-4are formed in a clockwise order in the region1004acorresponding to four pixels included in the solid-state imaging device1003, and the light shielding film5is formed between the pixels (pixel boundary).

The region1004acorresponding to four pixels is equivalent to the Q4region which is a right upper peripheral portion in the pixel region1004-G illustrated inFIG.4(d).

The pixel1004a-1includes a concavo-convex portion14a-1, and the concavo-convex portion14a-1has a point-symmetrical shape with the center of the concavo-convex portion14a-1as a point of symmetry and has a rectangular shape. The pixel1004a-2includes a concavo-convex portion14a-2, and the concavo-convex portion14a-2has a point-symmetrical shape with the center of the concavo-convex portion14a-2as a point of symmetry and has a rectangular shape. The pixel1004a-3includes a concavo-convex portion14a-3, and the concavo-convex portion14a-3has a point-symmetrical shape with the center of the concavo-convex portion14a-3as a point of symmetry and has a rectangular shape. The pixel1004a-4includes a concavo-convex portion14a-4, and the concavo-convex portion14a-4has a point-symmetrical shape with the center of the concavo-convex portion14a-4as a point of symmetry and has a rectangular shape. In addition, the number of irregularities of the concavo-convex portions14a-1to14a-4is larger than the number of irregularities of the concavo-convex portions13a-1to13a-4.

Each of the concavo-convex portions14a-1to14a-4is mainly formed in a left lower portion of the pixel with respect to the pixel center t of each of the pixels1004a-1to1004a-4, and thus it is possible to prevent the reflection of right oblique incident light and efficiently confine light to improve the quantum efficiency. In addition, the concavo-convex portions14a-1to14a-4are not formed to the light shielding film5between the pixels, and a flat portion is formed on a peripheral edge of each of the four pixels1004a-1to1004a-4, and thus scattering may not occur due to the concavo-convex portion. In this case, there is no light leakage to the adjacent pixels, and thus color mixing can be prevented.

As illustrated inFIG.4(b), four pixels1004b-1to1004b-4are formed in a clockwise order in the region1004bcorresponding to four pixels included in the solid-state imaging device1003, and the light shielding film5is formed between the pixels (pixel boundary).

The region1004bcorresponding to four pixels is equivalent to a Q4region which is a right upper peripheral portion in the pixel region1004-G illustrated inFIG.4(d).

The pixel1004b-1includes a concavo-convex portion14b-1, and the concavo-convex portion14b-1has a point-symmetrical shape with the center of the concavo-convex portion14b-1as a point of symmetry and has a rectangular shape. The pixel1004b-2includes a concavo-convex portion14b-2, and the concavo-convex portion14b-2has a point-symmetrical shape with the center of the concavo-convex portion14b-2as a point of symmetry and has a rectangular shape. The pixel1004b-3includes a concavo-convex portion14b-3, and the concavo-convex portion14b-3has a point-symmetrical shape with the center of the concavo-convex portion14b-3as a point of symmetry and has a rectangular shape. The pixel1004b-4includes a concavo-convex portion14b-4, and the concavo-convex portion14b-4has a point-symmetrical shape with the center of the concavo-convex portion14b-4as a point of symmetry and has a rectangular shape. In addition, a pitch (d4b) of each of the concavo-convex portions14b-1to14b-4is smaller than a pitch (d3a) of each of the concavo-convex portions13a-1to13a-4, and the number of irregularities of each of the concavo-convex portions14b-1to14b-4is larger than the number of irregularities of each of the concavo-convex portions13a-1to13a-4.

Each of the concavo-convex portions14b-1to14b-4is mainly formed in a left lower portion of the pixel with respect to the pixel center t of each of the pixels1004b-1to1004b-4, and thus it is possible to prevent the reflection of right oblique incident light and efficiently confine light to improve the quantum efficiency. In addition, the concavo-convex portions14b-1to14b-4are not formed to the light shielding film5between the pixels, and a flat portion is formed on a peripheral edge of each of the four pixels1004b-1to1004b-4, and thus scattering may not occur due to the concavo-convex portion. In this case, there is no light leakage to the adjacent pixels, and thus color mixing can be prevented.

As illustrated inFIG.4(c), four pixels1004c-1to1004c-4are formed in a clockwise order in the region1004ccorresponding to four pixels included in the solid-state imaging device1003, and the light shielding film5is formed between the pixels (pixel boundary).

The region1004ccorresponding to four pixels is equivalent to the Q4region which is a right upper peripheral portion in the pixel region1004-G illustrated inFIG.4(d).

The pixel1004c-1includes a concavo-convex portion14c-1, and the concavo-convex portion14c-1has a point-symmetrical shape with the center of the concavo-convex portion14c-1as a point of symmetry and has a polygonal shape. The pixel1004c-2includes a concavo-convex portion14c-2, and the concavo-convex portion14c-2has a point-symmetrical shape with the center of the concavo-convex portion14c-2as a point of symmetry and has a polygonal shape. The pixel1004c-3includes a concavo-convex portion14c-3, and the concavo-convex portion14c-3has a point-symmetrical shape with the center of the concavo-convex portion14c-3as a point of symmetry and has a polygonal shape. The pixel1004c-4includes a concavo-convex portion14c-4, and the concavo-convex portion14c-4has a point-symmetrical shape with the center of the concavo-convex portion14c-4as a point of symmetry and has a polygonal shape. Note that each of the concavo-convex portions14c-1to14c-4has a point-symmetrical shape with the center of each of the concavo-convex portions as a point of symmetry, but may have an asymmetrical shape.

Each of the concavo-convex portions14c-1to14c-4is mainly formed in a left lower portion of the pixel with respect to the pixel center t of each of the pixels1004c-1to1004c-4, and thus it is possible to prevent the reflection of right oblique incident light and efficiently confine light to improve the quantum efficiency. In addition, the concavo-convex portions14c-1to14c-4are not formed to the light shielding film5between the pixels, and a flat portion is formed on a peripheral edge of each of the four pixels1004c-1to1004c-4, and thus scattering may not occur due to the concavo-convex portion. In this case, there is no light leakage to the adjacent pixels, and thus color mixing can be prevented. Since each of the concavo-convex portions14c-1to14c-4has a polygonal shape, the concavo-convex portion more efficiently covers a light converging region of right oblique incident light and efficiently confines light to improve a quantum effect, thereby further contributing to the uniformity of sensitivity in the chip (in the substrate).

As illustrated inFIG.5(a), in the region1005acorresponding to four pixels included in the solid-state imaging device1003, four pixels1005a-1to1005a-4are formed in a clockwise order, and the light shielding film5is formed between the pixels (pixel boundary).

The region1005acorresponding to four pixels is equivalent to an R5region which is a right upper peripheral edge (the vicinity of a right upper vertex portion in the pixel region1005-G) of the right upper peripheral portion in the pixel region1005-G illustrated inFIG.5(d).

The pixel1005a-1includes a concavo-convex portion15a-1, and the concavo-convex portion15a-1has a point-symmetrical shape with the center of the concavo-convex portion15a-1as a point of symmetry and has a rectangular shape. The pixel1005a-2includes a concavo-convex portion15a-2, and the concavo-convex portion15a-2has a point-symmetrical shape with the center of the concavo-convex portion15a-2as a point of symmetry and has a rectangular shape. The pixel1005a-3includes a concavo-convex portion15a-3, and the concavo-convex portion15a-3has a point-symmetrical shape with the center of the concavo-convex portion15a-3as a point of symmetry and has a rectangular shape. The pixel1005a-4includes a concavo-convex portion15a-4, and the concavo-convex portion15a-4has a point-symmetrical shape with the center of the concavo-convex portion15a-4as a point of symmetry and has a rectangular shape. In addition, the number of irregularities of the concavo-convex portions15a-1to15a-4is larger than the number of irregularities of the concavo-convex portions14a-1to14a-4.

Each of the concavo-convex portions15a-1to15a-4is mainly formed in a left lower portion of the pixel with respect to the pixel center t of each of the pixels1005a-1to1005a-4, and thus it is possible to prevent the reflection of right oblique incident light and efficiently confine light to improve the quantum efficiency. In addition, the concavo-convex portions15a-1to15a-4are not formed to the light shielding film5between the pixels, and a flat portion is formed on a peripheral edge of each of the four pixels1005a-1to1005a-4, and thus scattering may not occur due to the concavo-convex portion. In this case, there is no light leakage to the adjacent pixels, and thus color mixing can be prevented.

As illustrated inFIG.5(b), four pixels1005b-1to1005b-4are formed in a clockwise order in the region1005bcorresponding to four pixels included in the solid-state imaging device1003, and the light shielding film5is formed between the pixels (pixel boundary).

The region1005bcorresponding to four pixels is equivalent to the R5region which is a right upper peripheral edge (the vicinity of a right upper vertex portion in the pixel region1005-G) of the right upper peripheral portion in the pixel region1005-G illustrated inFIG.5(d).

The pixel1005b-1includes a concavo-convex portion15b-1, and the concavo-convex portion15b-1has a point-symmetrical shape with the center of the concavo-convex portion15b-1as a point of symmetry and has a rectangular shape. The pixel1005b-2includes a concavo-convex portion15b-2, and the concavo-convex portion15b-2has a point-symmetrical shape with the center of the concavo-convex portion15b-2as a point of symmetry and has a rectangular shape. The pixel1005b-3includes a concavo-convex portion15b-3, and the concavo-convex portion15b-3has a point-symmetrical shape with the center of the concavo-convex portion15b-3as a point of symmetry and has a rectangular shape. The pixel1005b-4includes a concavo-convex portion15b-4, and the concavo-convex portion15b-4has a point-symmetrical shape with the center of the concavo-convex portion15b-4as a point of symmetry and has a rectangular shape. In addition, a pitch (d5b) of each of the concavo-convex portions15b-1to15b-4is smaller than a pitch (d4b) of each of the concavo-convex portions14b-1to14b-4, and the number of irregularities of each of the concavo-convex portions15b-1to15b-4is larger than the number of irregularities of each of the concavo-convex portions14b-1to14b-4.

Each of the concavo-convex portions15b-1to15b-4is mainly formed in a left lower portion of the pixel with respect to the pixel center t of each of the pixels1005b-1to1005b-4, and thus it is possible to prevent the reflection of right oblique incident light and efficiently confine light to improve the quantum efficiency. In addition, the concavo-convex portions15b-1to15b-4are not formed to the light shielding film5between the pixels, and a flat portion is formed on a peripheral edge of each of the four pixels1005b-1to1005b-4, and thus scattering may not occur due to the concavo-convex portion. In this case, there is no light leakage to the adjacent pixels, and thus color mixing can be prevented.

As illustrated inFIG.5(c), four pixels1005c-1to1005c-4are formed in a clockwise order in the region1005ccorresponding to four pixels included in the solid-state imaging device1003, and the light shielding film5is formed between the pixels (pixel boundary).

The region1005ccorresponding to four pixels is equivalent to the R5region which is a right upper peripheral edge (the vicinity of a right upper vertex portion in the pixel region1005-G) of the right upper peripheral portion in the pixel region1005-G illustrated inFIG.5(d).

The pixel1005c-1includes a concavo-convex portion15c-1, and the concavo-convex portion15c-1has a point-symmetrical shape with the center of the concavo-convex portion15c-1as a point of symmetry and has a polygonal shape. The pixel1005c-2includes a concavo-convex portion15c-2, and the concavo-convex portion15c-2has a point-symmetrical shape with the center of the concavo-convex portion15c-2as a point of symmetry and has a polygonal shape. The pixel1005c-3includes a concavo-convex portion15c-3, and the concavo-convex portion15c-3has a point-symmetrical shape with the center of the concavo-convex portion15c-3as a point of symmetry and has a polygonal shape. The pixel1005c-4includes a concavo-convex portion15c-4, and the concavo-convex portion15c-4has a point-symmetrical shape with the center of the concavo-convex portion15c-4as a point of symmetry and has a polygonal shape. Note that each of the concavo-convex portions15c-1to15c-4has a point-symmetrical shape with the center of each of the concavo-convex portions as a point of symmetry, but may have an asymmetrical shape.

Each of the concavo-convex portions15c-1to15c-4is mainly formed in a left lower portion of the pixel with respect to the pixel center t of each of the pixels1005c-1to1005c-4, and thus it is possible to prevent the reflection of right oblique incident light and efficiently confine light to improve the quantum efficiency. In addition, the concavo-convex portions15c-1to15c-4are not formed to the light shielding film5between the pixels, and a flat portion is formed on a peripheral edge of each of the four pixels1005c-1to1005c-4, and thus scattering may not occur due to the concavo-convex portion. In this case, there is no light leakage to the adjacent pixels, and thus color mixing can be prevented. Since each of the concavo-convex portions15c-1to15c-4has a polygonal shape, the concavo-convex portion more efficiently covers a light converging region of right oblique incident light and efficiently confines light to improve a quantum effect, thereby further contributing to the uniformity of sensitivity in the chip (in the substrate).

As described above, the number of irregularities of the concavo-convex portion increases from the P3region (the center portion of the pixel region) to the Q4region and the R5region, the number of pitches increases, and it is possible to achieve the uniformity of sensitivity in the chip (in the substrate) by changing a shape (changing a rectangular shape to a polygonal shape). That is, it is possible to improve contrast unevenness illustrated inFIG.3(b),FIG.4(d), andFIG.5(d)by the solid-state imaging device according to the third embodiment (Example 3 of a solid-state imaging device) of the present technology.

The above-described contents of the solid-state imaging device according to the third embodiment (Example 3 of a solid-state imaging device) of the present technology can be applied to the above-described solid-state imaging devices according to the first and second embodiments of the present technology and solid-state imaging devices according to fourth to seventh embodiments of the present technology to be described later, unless there is no particular technical contradiction.

A solid-state imaging device according to a fourth embodiment (Example 4 of a solid-state imaging device) of the present technology will be described usingFIGS.6and7.FIG.6is a diagram illustrating a configuration example of the solid-state imaging device according to the fourth embodiment to which the present technology is applied. In more detail,FIG.6(a)is a cross-sectional view of a solid-state imaging device1600(solid-state imaging device1600a), andFIG.6(b)is a planar layout diagram of the solid-state imaging device1600(solid-state imaging device1600b).FIG.7is a diagram illustrating a configuration example of the solid-state imaging device according to the fourth embodiment to which the present technology is applied. In more detail,FIG.7(a)is a plan view of a region1007acorresponding to four pixels included in a solid-state imaging device1007,FIG.7(b)is a plan view of a region1007bcorresponding to four pixels included in the solid-state imaging device1007,FIG.7(c)is a plan view of a region1007ccorresponding to four pixels included in the solid-state imaging device1007, andFIG.7(d)is a diagram illustrating contrast unevenness in a pixel region1007-G.

The solid-state imaging device1600(solid-state imaging devices1600aand1600b) includes on-chip lenses1-1and1-2, color filters2-1G and2-2R, an insulating film4, and photoelectric conversion units6-1and6-2formed in a semiconductor substrate7in order from a light incident side, and light converging regions M1and M2are formed by right oblique incident light L6-1and L6-2converged therein. Concavo-convex portions (a convex portion has a spindle shape)16a-1and16a-2are formed, and the reflection of light is prevented by the concavo-convex portions (a convex portion has a spindle shape)16a-1and16a2. As illustrated inFIG.6(b), concavo-convex portions (a convex portion has a spindle shape)16b-1and16b-2are formed to cover the light converging regions M1and M2. The concavo-convex portions (a convex portion has a spindle shape)16a-1and16a-2can be manufactured by dry etching.

Next, description will be made usingFIG.7. As illustrated inFIG.7(a), four pixels1007a-1to1007a-4are formed in a clockwise order in the region1007acorresponding to four pixels included in the solid-state imaging device1007, and the light shielding film5is formed between the pixels (pixel boundary).

The region1007acorresponding to four pixels is equivalent to a P3region which is a central portion in the pixel region1007-G illustrated inFIG.7(d).

The pixel1007a-1includes a concavo-convex portion17a-1, and the concavo-convex portion17a-1has a point-symmetrical shape with a pixel center t of the pixel1007a-1as a point of symmetry and has a rectangular shape. The pixel1007a-2includes a concavo-convex portion17a-2, and the concavo-convex portion17a-2has a point-symmetrical shape with a pixel center t of the pixel1007a-2as a point of symmetry and has a rectangular shape. The pixel1007a-3includes a concavo-convex portion17a-3, and the concavo-convex portion17a-3has a point-symmetrical shape with a pixel center t of the pixel1007a-3as a point of symmetry and has a rectangular shape. The pixel1007a-4includes a concavo-convex portion17a-4, and the concavo-convex portion17a-4has a point-symmetrical shape with a pixel center t of the pixel1007a-4as a point of symmetry and has a rectangular shape. Note that the pixel center t corresponds to the centers of each of the concavo-convex portions17a-1to17a-4.

FIG.7(a-1) is an enlarged plan view of the concavo-convex portion17a-1illustrated inFIG.7(a), reference numerals17a-1A and17a-1C indicate a concave portion of the concavo-convex portion, and reference numeral17a-1B indicates a convex portion of the concavo-convex portion. One pitch is a length from the center of the concave portion17a-1A (the center of a lower side17a-1E) to the center of the concave portion17a-1C (the center of a lower side17a-1F). In addition, a half pitch is a length from the center of the concave portion17a-1A (the center of the lower side17a-1E) or the center of the concave portion17a-1C (the center of the lower side17a-1F) to the center of the convex portion17a-1B (the center of an upper side17a-1D). Further, in the present specification, the range of an oblique line portion (a range indicated by reference numeral V2) in the concavo-convex portion17a-1is set to be one unit of the concavo-convex portion. Thus, the concavo-convex portion17a-1is constituted by four units. In addition, similarly, each of the concavo-convex portion17a-2, the concavo-convex portion17a-3, and the concavo-convex portion17a-4is four units. Each of a concavo-convex portion17b-1, a concavo-convex portion17b-2, a concavo-convex portion17b-3, and a concavo-convex portion17b-4to be described below is nine units inFIG.7(b), and each of a concavo-convex portion17c-1, a concavo-convex portion17c-2, a concavo-convex portion17c-3, and a concavo-convex portion17c-4is 16 units inFIG.7(c).

FIG.7(a-2) is a cross-sectional view taken along line A2-B2illustrated inFIG.7(a-1). As illustrated inFIG.7(a-2), a convex portion of the concavo-convex portion17a-1has a spindle shape and has an upper side when seen in a cross-sectional view. Note that the concavo-convex portion17a-1can be manufactured by dry etching.

The concavo-convex portions17a-1to17a-4are formed in the center portion (a region surrounding the pixel center t) of each of the pixels1007a-1to1007a-4, and thus it is possible to efficiently confine vertically incident light to improve quantum efficiency. In addition, the concavo-convex portions17a-1to17a-4are not formed to the light shielding film5between the pixels, and a flat portion is formed on a peripheral edge of each of the four pixels1007a-1to1007a-4. Thus, there is no light leakage to the adjacent pixels, and color mixing can be prevented.

As illustrated inFIG.7(b), four pixels1007b-1to1007b-4are formed in a clockwise order in the region1007bcorresponding to four pixels included in the solid-state imaging device1007, and the light shielding film5is formed between the pixels (pixel boundary).

The region1007bcorresponding to four pixels is equivalent to a Q7region which is a right upper peripheral portion in the pixel region1007-G illustrated inFIG.7(d).

The pixel1007b-1includes a concavo-convex portion17b-1, and the concavo-convex portion17b-1has a point-symmetrical shape with the center of the concavo-convex portion17b-1as a point of symmetry and has a rectangular shape. The pixel1007b-2includes a concavo-convex portion17b-2, and the concavo-convex portion17b-2has a point-symmetrical shape with the center of the concavo-convex portion17b-2as a point of symmetry and has a rectangular shape. The pixel1007b-3includes a concavo-convex portion17b-3, and the concavo-convex portion17b-3has a point-symmetrical shape with the center of the concavo-convex portion17b-3as a point of symmetry and has a rectangular shape. The pixel1007b-4includes a concavo-convex portion17b-4, and the concavo-convex portion17b-4has a point-symmetrical shape with the center of the concavo-convex portion17b-4as a point of symmetry and has a rectangular shape. In addition, the number of irregularities of the concavo-convex portions17b-1to17b-4is larger than the number of irregularities of the concavo-convex portions17a-1to17a-4. By increasing the number of irregularities of the concavo-convex portions17b-1to17b-4, it is possible to increase sensitivity by more effectively preventing the reflection of right oblique light incident in the Q7region.

Each of the concavo-convex portions17b-1to17b-4is mainly formed in a left lower portion of the pixel (a left upper portion of the pixel may also be used) with respect to the pixel center t of each of the pixels1007b-1to1007b-4, and thus it is possible to prevent the reflection of right oblique incident light and efficiently confine light to improve the quantum efficiency. In a case where the concavo-convex portion is mainly formed in the right lower portion (or right upper portion) of the pixel, it is possible to prevent the reflection of left oblique incident light and efficiently confine light to improve quantum efficiency. In addition, the concavo-convex portions17b-1to17b-4are not formed to the light shielding film5between the pixels, and a flat portion is formed on a peripheral edge of each of the four pixels1007b-1to1007b-4, and thus scattering may not occur due to the concavo-convex portion. In this case, there is no light leakage to the adjacent pixels, and thus color mixing can be prevented.

As illustrated inFIG.7(c), four pixels1007c-1to1007c-4are formed in a clockwise order in the region1007ccorresponding to four pixels included in the solid-state imaging device1007, and the light shielding film5is formed between the pixels (pixel boundary).

The region1007ccorresponding to four pixels is equivalent to an R7region which is a right upper peripheral edge (the vicinity of a right upper vertex portion in the pixel region1007-G) of the right upper peripheral portion in the pixel region1007-G illustrated inFIG.7(d).

The pixel1007c-1includes a concavo-convex portion17c-1, and the concavo-convex portion17c-1has a point-symmetrical shape with the center of the concavo-convex portion17c-1as a point of symmetry and has a rectangular shape. The pixel1007c-2includes a concavo-convex portion17c-2, and the concavo-convex portion17c-2has a point-symmetrical shape with the center of the concavo-convex portion17c-2as a point of symmetry and has a rectangular shape. The pixel1007c-3includes a concavo-convex portion17c-3, and the concavo-convex portion17c-3has a point-symmetrical shape with the center of the concavo-convex portion17c-3as a point of symmetry and has a rectangular shape. The pixel1007c-4includes a concavo-convex portion17c-4, and the concavo-convex portion17c-4has a point-symmetrical shape with the center of the concavo-convex portion17c-4as a point of symmetry and has a rectangular shape. In addition, the number of irregularities of the concavo-convex portions17c-1to17c-4is larger than the number of irregularities of the concavo-convex portions17b-1to17b-4. By increasing the number of irregularities of the concavo-convex portions17c-1to17c-4, it is possible to increase sensitivity by more effectively preventing the reflection of right oblique light incident in the R7region.

Each of the concavo-convex portions17c-1to17c-4is mainly formed in a left lower portion of the pixel (a left upper portion of the pixel may also be used) with respect to the pixel center t of each of the pixels1007c-1to1007c-4, and thus it is possible to prevent the reflection of right oblique incident light and efficiently confine light to improve the quantum efficiency. In a case where the concavo-convex portion is mainly formed in the right lower portion (or right upper portion) of the pixel, it is possible to prevent the reflection of left oblique incident light and efficiently confine light to improve quantum efficiency. In addition, the concavo-convex portions17c-1to17c-4are not formed to the light shielding film5between the pixels, and a flat portion is formed on a peripheral edge of each of the four pixels1007c-1to1007c-4, and thus scattering may not occur due to the concavo-convex portion. In this case, there is no light leakage to the adjacent pixels, and thus color mixing can be prevented.

As described above, the number of irregularities of the concavo-convex portion increases from the P7region (the center portion of the pixel region) to the Q7region and the R7region, and it is possible to achieve the uniformity of sensitivity in the chip (in the substrate). That is, it is possible to improve contrast unevenness illustrated inFIG.7(d)by the solid-state imaging device according to the fourth embodiment (Example 4 of a solid-state imaging device) of the present technology.

The above-described contents of the solid-state imaging device according to the fourth embodiment (Example 4 of a solid-state imaging device) of the present technology can be applied to the above-described solid-state imaging device according to the first to third embodiments of the present technology and solid-state imaging devices according to fifth to seventh embodiments of the present technology to be described later, unless there is no particular technical contradiction.

A solid-state imaging device according to a fifth embodiment (Example 5 of a solid-state imaging device) of the present technology will be described usingFIGS.8to10.FIG.8is a diagram illustrating a configuration example of the solid-state imaging device according to the fifth embodiment of the present technology. In more detail,FIG.8(a)is a plan view of a region1008acorresponding to four pixels included in a solid-state imaging device1008, andFIG.8(b)is a diagram illustrating contrast unevenness in a pixel region1008-G.FIG.9is a diagram illustrating a configuration example of the solid-state imaging device according to the fifth embodiment of the present technology. In more detail,FIG.9(a)is a plan view of a region1009acorresponding to four pixels included in the solid-state imaging device1008,FIG.9(b)is a plan view of a region1009bcorresponding to four pixels included in the solid-state imaging device1008,FIG.9(c)is a plan view of a region1009ccorresponding to four pixels included in the solid-state imaging device1008, andFIG.9(d)is a diagram illustrating contrast unevenness in a pixel region1008-G.FIG.10is a diagram illustrating a configuration example of the solid-state imaging device according to the fifth embodiment of the present technology. In more detail,FIG.10(a)is a plan view of a region1010acorresponding to four pixels included in the solid-state imaging device1008,FIG.10(b)is a plan view of a region1010bcorresponding to four pixels included in the solid-state imaging device1008,FIG.10(c)is a plan view of a region1010ccorresponding to four pixels included in the solid-state imaging device1008, andFIG.10(d)is a diagram illustrating contrast unevenness in the pixel region1008-G.

As illustrated inFIG.8, four pixels1008a-1to1008a-4are formed in a clockwise order in the region1008acorresponding to four pixels included in the solid-state imaging device1008, and a light shielding film5is formed between the pixels (pixel boundary).

The region1008acorresponding to four pixels is equivalent to a P8region which is a central portion in the pixel region1008-G illustrated inFIG.8(b).

The pixel1008a-1includes a concavo-convex portion18a-1, and the concavo-convex portion18a-1has a point-symmetrical shape with a pixel center t of the pixel1008a-1as a point of symmetry and has a rectangular shape. The pixel1008a-2includes a concavo-convex portion18a-2, and the concavo-convex portion18a-2has a point-symmetrical shape with a pixel center t of the pixel1008a-2as a point of symmetry and has a rectangular shape. The pixel1008a-3includes a concavo-convex portion18a-3, and the concavo-convex portion18a-3has a point-symmetrical shape with a pixel center t of the pixel1008a-3as a point of symmetry and has a rectangular shape. The pixel1008a-4includes a concavo-convex portion18a-4, and the concavo-convex portion18a-4has a point-symmetrical shape with a pixel center t of the pixel1008a-4as a point of symmetry and has a rectangular shape. Note that the pixel center t corresponds to the center of each of the concavo-convex portions18a-1to18a-4.

The concavo-convex portions18a-1to18a-4are formed in the center portion (a region surrounding the pixel center t) of each of the pixels1008a-1to1008a-4, and thus it is possible to efficiently confine vertically incident light to improve quantum efficiency. In addition, the concavo-convex portions18a-1to18a-4are not formed to the light shielding film5between the pixels, and a flat portion is formed on a peripheral edge of each of the four pixels1008a-1to1008a-4. Thus, there is no light leakage to the adjacent pixels, and color mixing can be prevented.

As illustrated inFIG.9(a), four pixels1009a-1to1009a-4are formed in a clockwise order in the region1009acorresponding to four pixels included in the solid-state imaging device1008, and the light shielding film5is formed between the pixels (pixel boundary).

The region1009acorresponding to four pixels is equivalent to a Q9region which is a right upper peripheral portion in the pixel region1008-G illustrated inFIG.9(d).

The pixel1009a-1includes a concavo-convex portion19a-1, and the concavo-convex portion19a-1has a point-symmetrical shape with the center of the concavo-convex portion19a-1as a point of symmetry and has a rectangular shape. The pixel1009a-2includes a concavo-convex portion19a-2, and the concavo-convex portion19a-2has a point-symmetrical shape with the center of the concavo-convex portion19a-2as a point of symmetry and has a rectangular shape. The pixel1009a-3includes a concavo-convex portion19a-3, and the concavo-convex portion19a-3has a point-symmetrical shape with the center of the concavo-convex portion19a-3as a point of symmetry and has a rectangular shape. The pixel1009a-4includes a concavo-convex portion19a-4, and the concavo-convex portion19a-4has a point-symmetrical shape with the center of the concavo-convex portion19a-4as a point of symmetry and has a rectangular shape. In addition, the number of irregularities of the concavo-convex portions19a-1to19a-4is larger than the number of irregularities of the concavo-convex portions18a-1to18a-4.

Each of the concavo-convex portions19a-1to19a-4is mainly formed in a left lower portion of the pixel with respect to the pixel center t of each of the pixels1009a-1to1009a-4, and thus it is possible to prevent the reflection of right oblique incident light and efficiently confine light to improve the quantum efficiency. In addition, the concavo-convex portions19a-1to19a-4are not formed to the light shielding film5between the pixels, and a flat portion is formed on a peripheral edge of each of the four pixels1009a-1to1009a-4, and thus scattering may not occur due to the concavo-convex portion. In this case, there is no light leakage to the adjacent pixels, and thus color mixing can be prevented.

As illustrated inFIG.9(b), four pixels1009b-1to1009b-4are formed in a clockwise order in the region1009bcorresponding to four pixels included in the solid-state imaging device1008, and the light shielding film5is formed between the pixels (pixel boundary).

The region1009bcorresponding to four pixels is equivalent to the Q9region which is a right upper peripheral portion in the pixel region1008-G illustrated inFIG.9(d).

The pixel1009b-1includes a concavo-convex portion19b-1, and the concavo-convex portion19b-1has a point-symmetrical shape with the center of the concavo-convex portion19b-1as a point of symmetry and has a rectangular shape. The pixel1009b-2includes a concavo-convex portion19b-2, and the concavo-convex portion19b-2has a point-symmetrical shape with the center of the concavo-convex portion19b-2as a point of symmetry and has a rectangular shape. The pixel1009b-3includes a concavo-convex portion19b-3, and the concavo-convex portion19b-3has a point-symmetrical shape with the center of the concavo-convex portion19b-3as a point of symmetry and has a rectangular shape. The pixel1009b-4includes a concavo-convex portion19b-4, and the concavo-convex portion19b-4has a point-symmetrical shape with the center of the concavo-convex portion19b-4as a point of symmetry and has a rectangular shape. In addition, a pitch (d9b) of each of the concavo-convex portions19b-1to19b-4is smaller than a pitch (d8a) of each of the concavo-convex portions18a-1to18a-4, and the number of irregularities of each of the concavo-convex portions19b-1to19b-4is larger than the number of irregularities of each of the concavo-convex portions18a-1to18a-4.

Each of the concavo-convex portions19b-1to19b-4is mainly formed in a left lower portion of the pixel with respect to the pixel center t of each of the pixels1009b-1to1009b-4, and thus it is possible to prevent the reflection of right oblique incident light and efficiently confine light to improve the quantum efficiency. In addition, the concavo-convex portions19b-1to19b-4are not formed to the light shielding film5between the pixels, and a flat portion is formed on a peripheral edge of each of the four pixels1009b-1to1009b-4, and thus scattering may not occur due to the concavo-convex portion. In this case, there is no light leakage to the adjacent pixels, and thus color mixing can be prevented.

As illustrated inFIG.9(c), four pixels1009c-1to1009c-4are formed in a clockwise order in the region1009ccorresponding to four pixels included in the solid-state imaging device1008, and the light shielding film5is formed between the pixels (pixel boundary).

The region1009ccorresponding to four pixels is equivalent to the Q9region which is a right upper peripheral portion in the pixel region1008-G G illustrated inFIG.9(d).

The pixel1009c-1includes a concavo-convex portion19c-1, and the concavo-convex portion19c-1has a point-symmetrical shape with the center of the concavo-convex portion19c-1as a point of symmetry and has a polygonal shape. The pixel1009c-2includes a concavo-convex portion19c-2, and the concavo-convex portion19c-2has a point-symmetrical shape with the center of the concavo-convex portion19c-2as a point of symmetry and has a polygonal shape. The pixel1009c-3includes a concavo-convex portion19c-3, and the concavo-convex portion19c-3has a point-symmetrical shape with the center of the concavo-convex portion19c-3as a point of symmetry and has a polygonal shape. The pixel1009c-4includes a concavo-convex portion19c-4, and the concavo-convex portion19c-4has a point-symmetrical shape with the center of the concavo-convex portion19c-4as a point of symmetry and has a polygonal shape. Note that each of the concavo-convex portions19c-1to19c-4has a point-symmetrical shape with the center of each of the concavo-convex portions as a point of symmetry, but may have an asymmetrical shape.

Each of the concavo-convex portions19c-1to19c-4is mainly formed in a left lower portion of the pixel with respect to the pixel center t of each of the pixels1009c-1to1009c-4, and thus it is possible to prevent the reflection of right oblique incident light and efficiently confine light to improve the quantum efficiency. In addition, the concavo-convex portions19c-1to19c-4are not formed to the light shielding film5between the pixels, and a flat portion is formed on a peripheral edge of each of the four pixels1009c-1to1009c-4, and thus scattering may not occur due to the concavo-convex portion. In this case, there is no light leakage to the adjacent pixels, and thus color mixing can be prevented. Since each of the concavo-convex portions19c-1to19c-4has a polygonal shape, the concavo-convex portion more efficiently covers a light converging region of right oblique incident light and efficiently confines light to improve a quantum effect, thereby further contributing to the uniformity of sensitivity in the chip (in the substrate).

As illustrated inFIG.10(a), four pixels1010a-1to1010a-4are formed in a clockwise order in the region1010acorresponding to four pixels included in the solid-state imaging device1008, and the light shielding film5is formed between the pixels (pixel boundary).

The region1010acorresponding to four pixels is equivalent to an R10region which is a right upper peripheral edge (the vicinity of a right upper vertex portion in the pixel region1008-G) of the right upper peripheral portion in the pixel region1008-G illustrated inFIG.10(d).

The pixel1010a-1includes a concavo-convex portion20a-1, and the concavo-convex portion20a-1has a point-symmetrical shape with the center of the concavo-convex portion20a-1as a point of symmetry and has a rectangular shape. The pixel1010a-2includes a concavo-convex portion20a-2, and the concavo-convex portion20a-2has a point-symmetrical shape with the center of the concavo-convex portion20a-2as a point of symmetry and has a rectangular shape. The pixel1010a-3includes a concavo-convex portion20a-3, and the concavo-convex portion20a-3has a point-symmetrical shape with the center of the concavo-convex portion20a-3as a point of symmetry and has a rectangular shape. The pixel1010a-4includes a concavo-convex portion20a-4, and the concavo-convex portion20a-4has a point-symmetrical shape with the center of the concavo-convex portion20a-4as a point of symmetry and has a rectangular shape. In addition, the number of irregularities of the concavo-convex portions20a-1to20a-4is larger than the number of irregularities of the concavo-convex portions19a-1to19a-4.

Each of the concavo-convex portions20a-1to20a-4is mainly formed in a left lower portion of the pixel with respect to the pixel center t of each of the pixels1010a-1to1010a-4, and thus it is possible to prevent the reflection of right oblique incident light and efficiently confine light to improve the quantum efficiency. In addition, the concavo-convex portions20a-1to20a-4are not formed to the light shielding film5between the pixels, and a flat portion is formed on a peripheral edge of each of the four pixels1010a-1to1010a-4, and thus scattering may not occur due to the concavo-convex portion. In this case, there is no light leakage to the adjacent pixels, and thus color mixing can be prevented.

As illustrated inFIG.10(b), four pixels1010b-1to1010b-4are formed in a clockwise order in the region1010bcorresponding to four pixels included in the solid-state imaging device1008, and the light shielding film5is formed between the pixels (pixel boundary).

The region1010bcorresponding to four pixels is equivalent to the R10region which is a right upper peripheral edge (the vicinity of a right upper vertex portion in the pixel region1008-G) of the right upper peripheral portion in the pixel region1008-G illustrated inFIG.10(d).

The pixel1010b-1includes a concavo-convex portion20b-1, and the concavo-convex portion20b-1has a point-symmetrical shape with the center of the concavo-convex portion20b-1as a point of symmetry and has a rectangular shape. The pixel1010b-2includes a concavo-convex portion20b-2, and the concavo-convex portion20b-2has a point-symmetrical shape with the center of the concavo-convex portion20b-2as a point of symmetry and has a rectangular shape. The pixel1010b-3includes a concavo-convex portion20b-3, and the concavo-convex portion20b-3has a point-symmetrical shape with the center of the concavo-convex portion20b-3as a point of symmetry and has a rectangular shape. The pixel1010b-4includes a concavo-convex portion20b-4, and the concavo-convex portion20b-4has a point-symmetrical shape with the center of the concavo-convex portion20b-4as a point of symmetry and has a rectangular shape. In addition, a pitch (d10b) of each of the concavo-convex portions20b-1to20b-4is smaller than a pitch (d9b) of each of the concavo-convex portions19b-1to19b-4, and the number of irregularities of each of the concavo-convex portions20b-1to20b-4is larger than the number of irregularities of each of the concavo-convex portions19b-1to19b-4.

Each of the concavo-convex portions20b-1to20b-4is mainly formed in a left lower portion of the pixel with respect to the pixel center t of each of the pixels1010b-1to1010b-4, and thus it is possible to prevent the reflection of right oblique incident light and efficiently confine light to improve the quantum efficiency. In addition, the concavo-convex portions20b-1to20b-4are not formed to the light shielding film5between the pixels, and a flat portion is formed on a peripheral edge of each of the four pixels1010b-1to1010b-4, and thus scattering may not occur due to the concavo-convex portion. In this case, there is no light leakage to the adjacent pixels, and thus color mixing can be prevented.

As illustrated inFIG.10(c), four pixels1010c-1to1010c-4are formed in a clockwise order in the region1010ccorresponding to four pixels included in the solid-state imaging device1008, and the light shielding film5is formed between the pixels (pixel boundary).

The region1010ccorresponding to four pixels is equivalent to the R10region which is a right upper peripheral edge (the vicinity of a right upper vertex portion in the pixel region1008-G) of the right upper peripheral portion in the pixel region1008-G illustrated inFIG.10(d).

The pixel1010c-1includes a concavo-convex portion20c-1, and the concavo-convex portion20c-1has a point-symmetrical shape with the center of the concavo-convex portion20c-1as a point of symmetry and has a polygonal shape. The pixel1010c-2includes a concavo-convex portion20c-2, and the concavo-convex portion20c-2has a point-symmetrical shape with the center of the concavo-convex portion20c-2as a point of symmetry and has a polygonal shape. The pixel1010c-3includes a concavo-convex portion20c-3, and the concavo-convex portion20c-3has a point-symmetrical shape with the center of the concavo-convex portion20c-3as a point of symmetry and has a polygonal shape. The pixel1010c-4includes a concavo-convex portion20c-4, and the concavo-convex portion20c-4has a point-symmetrical shape with the center of the concavo-convex portion20c-4as a point of symmetry and has a polygonal shape. Note that each of the concavo-convex portions20c-1to20c-4has a point-symmetrical shape with the center of each of the concavo-convex portions as a point of symmetry, but may have an asymmetrical shape.

Each of the concavo-convex portions20c-1to20c-4is mainly formed in a left lower portion of the pixel with respect to the pixel center t of each of the pixels1010c-1to1010c-4, and thus it is possible to prevent the reflection of right oblique incident light and efficiently confine light to improve the quantum efficiency. In addition, the concavo-convex portions20c-1to20c-4are not formed to the light shielding film5between the pixels, and a flat portion is formed on a peripheral edge of each of the four pixels1010c-1to1010c-4, and thus scattering may not occur due to the concavo-convex portion. In this case, there is no light leakage to the adjacent pixels, and thus color mixing can be prevented. Since each of the concavo-convex portions20c-1to20c-4has a polygonal shape, the concavo-convex portion more efficiently covers a light converging region of right oblique incident light and efficiently confines light to improve a quantum effect, thereby further contributing to the uniformity of sensitivity in the chip (in the substrate).

As described above, the number of irregularities of the concavo-convex portion increases from the P8region (the center portion of the pixel region) to the Q9region and the R10region, the number of pitches increases, and it is possible to achieve the uniformity of sensitivity in the chip (in the substrate) by changing a shape (changing a rectangular shape to a polygonal shape). That is, it is possible to improve contrast unevenness illustrated inFIG.8(b),FIG.9(d), andFIG.10(d)by the solid-state imaging device according to the fifth embodiment (Example 5 of a solid-state imaging device) of the present technology.

The above-described contents of the solid-state imaging device according to the fifth embodiment (Example 5 of a solid-state imaging device) of the present technology can be applied to the above-described solid-state imaging devices according to the first to fourth embodiments of the present technology and solid-state imaging devices according to sixth and seventh embodiments of the present technology to be described later, unless there is no particular technical contradiction.

A solid-state imaging device according to a sixth embodiment (Example 6 of a solid-state imaging device) of the present technology will be described usingFIG.11.FIG.11is a diagram illustrating a configuration example of four pixels included in the solid-state imaging device according to the sixth embodiment to which the present technology is applied, and more specifically, is a plan view of a region1011acorresponding to four pixels included in the solid-state imaging device according to the sixth embodiment.

As illustrated inFIG.11, four pixels1011a-1to1011a-4are formed in a clockwise order in the region1011acorresponding to four pixels, and the light shielding film5is formed between the pixels (pixel boundary).

The pixel1011a-1includes a concavo-convex portion21a-1, the pixel1011a-2includes a concavo-convex portion21a-2, the pixel1011a-3includes a concavo-convex portion21a-3, and the pixel1011a-4includes a concavo-convex portion21a-4.

As illustrated inFIG.11, a pitch of the concavo-convex portion21a-2is deviated by a half pitch in a Y-axis direction (upward inFIG.11) with respect to the concavo-convex portion21a-1. Note that, in order to efficiently confine light and improve a quantum effect in accordance with the incidence direction of incident light (to appropriately deal with a focal region), a deviation width may be set arbitrarily, and examples of the deviation width includes one pitch, a quarter pitch, and the like. Here, a length from the center of a concave portion21a-1A to the center of a concave portion21a-C is set to be one pitch, and a length from the center of the concave portion21a-1A or the concave portion21a-1C to the center of a convex portion21a-1B is set to be a half pitch.

As illustrated inFIG.11, the pitch of the concavo-convex portion21a-3is deviated by a half pitch in the Y-axis direction (upward inFIG.11) with respect to the concavo-convex portion21a-4. Note that, in order to efficiently confine light and improve a quantum effect in accordance with the incidence direction of incident light (to appropriately deal with a focal region), a deviation width may be set arbitrarily, and examples of the deviation width includes one pitch, a quarter pitch, and the like. Here, one pitch and a half pitch are defined as described above.

The above-described contents of the solid-state imaging device according to the sixth embodiment (Example 6 of a solid-state imaging device) of the present technology can be applied to the above-described solid-state imaging devices according to the first to fifth embodiments of the present technology and a solid-state imaging device according to a seventh embodiment of the present technology to be described later, unless there is no particular technical contradiction.

A solid-state imaging device according to a seventh embodiment (Example 7 of a solid-state imaging device) of the present technology will be described usingFIG.12.FIG.12is a diagram illustrating a configuration example of four pixels included in the solid-state imaging device according to the seventh embodiment to which the present technology is applied, and more specifically, is a plan view of a region1012acorresponding to four pixels included in the solid-state imaging device according to the seventh embodiment.

As illustrated inFIG.12, four pixels1012a-1to1012a-4are formed in a clockwise order in the region1012acorresponding to four pixels, and the light shielding film5is formed between the pixels (pixel boundary).

The pixel1012a-1includes a concavo-convex portion22a-1, the pixel1012a-2includes a concavo-convex portion22a-2, the pixel1012a-3includes a concavo-convex portion22a-3, and the pixel1012a-4includes a concavo-convex portion22a-4.

As illustrated inFIG.12, a pitch of the concavo-convex portion22a-2is deviated by a half pitch in an X-axis direction (rightward inFIG.11) with respect to the concavo-convex portion22a-1. Note that, in order to efficiently confine light and improve a quantum effect in accordance with the incidence direction of incident light (to appropriately deal with a focal region), a deviation width may be set arbitrarily, and examples of the deviation width includes one pitch, a quarter pitch, and the like. Here, a length from the center of a concave portion22a-1A to the center of a concave portion22a-C is set to be one pitch, and a length from the center of the concave portion22a-1A or the concave portion22a-1C to the center of a convex portion22a-1B is set to be a half pitch.

As illustrated inFIG.12, a pitch of the concavo-convex portion22a-3is deviated by a half pitch in the X-axis direction (rightward inFIG.12) with respect to the concavo-convex portion22a-4. Note that, in order to efficiently confine light and improve a quantum effect in accordance with the incidence direction of incident light (to appropriately deal with a focal region), a deviation width may be set arbitrarily, and examples of the deviation width includes one pitch, a quarter pitch, and the like. Here, one pitch and a half pitch are defined as described above.

The above-described contents of the solid-state imaging device according to the seventh embodiment (Example 7 of a solid-state imaging device) of the present technology can be applied to the above-described solid-state imaging devices according to the first to sixth embodiments of the present technology, unless there is no particular technical contradiction.

Electronic equipment according to an eighth embodiment of the present technology is electronic equipment on which the solid-state imaging device among the solid-state imaging devices according to any one of the first to seventh embodiments of the present technology is mounted.

10. Example of Use of Solid-State Imaging Device to which the Present Technology is Applied

FIG.14is a diagram illustrating an example in which the solid-state imaging devices according to the first to seventh embodiments of the present technology are used as an image sensor (solid-state imaging device).

The above-described solid-state imaging devices according to the first to seventh embodiments can be used in various cases where light such as visible light, infrared light, ultraviolet light, and X rays is sensed as follows. That is, as illustrated inFIG.14, the solid-state imaging device according to any one of the first to seventh embodiments can be used in devices (for example, the electronic equipment according to the eighth embodiment described above) which are used in, for example, a field of appreciation in which an image provided for appreciation is captured, a field of traffic, a field of home appliances, a field of medical treatment and health care, a field of security, a field of beauty, a field of sports, and a field of agriculture.

Specifically, in a field of appreciation, the solid-state imaging device according to any one of the first to seventh embodiments can be used in devices for capturing an image provided for appreciation, such as a digital camera, a smartphone, and a mobile phone with a camera function.

In a field of traffic, the solid-state imaging device according to any one of the first to seventh embodiments can be used in devices provided for traffic, such as an in-vehicle sensor that images the front, rear, surroundings, inside, and the like of a vehicle, a monitoring camera that monitors traveling vehicles and roads, and a distance measuring sensor that measures a distance between vehicles, and the like for safe driving such as automatic stop, recognition of a driver's conditions, and the like.

In a field of home appliances, the solid-state imaging device according to any one of the first to seventh embodiments can be used in devices provided for home appliances, such as a television receiver, a refrigerator, and an air conditioner, for example, in order to image a user's gesture and operate equipment in response to the gesture.

In a field of medical treatment and health care, the solid-state imaging device according to any one of the first to seventh embodiments can be used in devices provided for medical treatment and health care, such as an endoscope and a device that performs angiography by receiving infrared light.

In a field of security, the solid-state imaging device according to any one of the first to seventh embodiments can be used in devices provided for security, such as a surveillance camera for crime prevention and a camera for person authentication.

In a field of beauty, the solid-state imaging device according to any one of the first to seventh embodiments can be used in devices provided for beauty such as a skin measuring instrument that images the skin and a microscope that images the scalp.

In a field of sports, the solid-state imaging device according to any one of the first to seventh embodiments can be used in devices provided for sports, such as an action camera and a wearable camera for sports applications.

In a field of agriculture, the solid-state imaging device according to any one of the first to seventh embodiments can be used in devices provided for agriculture, such as a camera that monitors the conditions of fields and crops.

Next, an example in which the solid-state imaging devices according to the first to seventh embodiments of the present technology are used will be specifically described. For example, the solid-state imaging device according to any one of the first to seventh embodiments described above is used. Specifically, a solid-state imaging device101can be applied to any type of electronic equipment equipped with an imaging function, for example, a camera system such as a digital still camera or a video camera, and a mobile phone having an imaging function. As an example, a schematic configuration of electronic equipment102(camera) is illustrated inFIG.15. The electronic equipment102is a video camera that can capture a still image or a moving image, and includes the solid-state imaging device101, an optical system (optical lens)310, a shutter device311, a driving portion313that drives the solid-state imaging device101and the shutter device311, and a signal processing unit312.

The optical system310guides image light (incident light) from a subject to a pixel portion101aof the solid-state imaging device101. The optical system310may be constituted by a plurality of optical lenses. The shutter device311controls a light irradiation period and a light shielding period for the solid-state imaging device101. The driving portion313controls a transfer operation of the solid-state imaging device101and a shutter operation of the shutter device311. The signal processing unit312performs various signal processing on signals output from the solid-state imaging device101. A video signal Dout after signal processing is stored in a storage medium such as a memory or is output to a monitor or the like.

11. Example of Application to Endoscopic Surgery System

The present technology can be applied to various products. For example, the technology according to the present disclosure (the present technology) may be applied to an endoscopic surgery system.

FIG.16is a diagram illustrating an example of a schematic configuration of an endoscopic surgery system to which the technology according to the present disclosure (the present technology) can be applied.

FIG.16shows a state where a surgeon (doctor)11131is performing a surgical operation on a patient11132on a patient bed11133by using the endoscopic surgery system11000. As illustrated in the drawing, the endoscopic surgery system11000is constituted by an endoscope11100, another surgical tool11110such as a pneumoperitoneum tube11111or an energy treatment tool11112, a support arm device11120that supports the endoscope11100, and a cart11200in which various devices for endoscopic surgery are mounted.

The endoscope11100includes a lens barrel11101of which a region having a predetermined length from a distal end is inserted into a body cavity of the patient11132, and a camera head11102connected to a base end of the lens barrel11101. In the example illustrated in the drawing, the endoscope11100configured as a so-called rigid endoscope having the rigid lens barrel11101is illustrated, but the endoscope11100may be configured as a so-called soft endoscope having a soft lens barrel.

An opening in which an objective lens is fitted is provided at a distal end of the lens barrel11101. A light source device11203is connected to the endoscope11100, and light generated by the light source device11203is guided to the tip of the lens barrel by the light guide extending into the lens barrel11101, and is emitted to an observation target in the body cavity of the patient11132via the objective lens. Here, the endoscope11100may be a direct endoscope or may be a perspective endoscope or a side endoscope.

An optical system and an imaging element are provided inside the camera head11102, and the reflected light (observation light) from the observation target converges on the imaging element by the optical system. The observation light is photoelectrically converted by the imaging element, and an electrical signal corresponding to the observation light, that is, an image signal corresponding to an observation image is generated. The image signal is transmitted to a camera control unit (CCU)11201as RAW data.

The CCU11201is constituted by a central processing unit (CPU), a graphics processing unit (GPU), or the like, and generally controls operations of the endoscope11100and the display device11202. In addition, the CCU11201receives an image signal from the camera head11102, and performs various types of image processing for displaying an image based on the image signal, for example, development processing (demosaic processing) on the image signal.

The display device11202displays an image based on the image signal subjected to the image processing by the CCU11201under the control of the CCU11201.

The light source device11203is constituted by a light source such as a light emitting diode (LED), and supplies the endoscope11100with irradiation light for imaging a surgical part or the like.

An input device11204is an input interface for the endoscopic surgery system11000. A user can input various types of information and input an instruction to the endoscopic surgery system11000via the input device11204. For example, the user inputs an instruction to change imaging conditions (the type of irradiation light, a magnification, a focal distance, and the like) and the like by the endoscope11100.

A treatment tool control device11205controls the driving of an energy treatment tool11112for cauterizing or incising tissue, sealing a blood vessel, or the like. In order to secure a field of view of the endoscope11100and secure an operation space of the surgeon, a pneumoperitoneum device11206sends gas into the body cavity of the patient11132via the pneumoperitoneum tube11111in order to inflate the body cavity. A recorder11207is a device that can record various types of information related to surgery. A printer11208is a device that can print various types of information related to surgery in various formats such as text, images and graphs.

Note that the light source device11203that supplies irradiation light for imaging a surgical part to the endoscope11100can be constituted by, for example, an LED, a laser light source, or a white light source constituted by a combination thereof. In a case where a white light source is constituted by a combination of RGB laser light sources, the output intensity of each color (each wavelength) and an output timing can be controlled with high accuracy, and thus white balance of a captured image can be adjusted in the light source device11203. Further, in this case, an observation target is irradiated with laser beams from the RGB laser light sources in a time-division manner, and the driving of the imaging element of the camera head11102is controlled in synchronization with the irradiation timing, whereby it is also possible to capture images corresponding to RGB in a time-division manner. According to the method, a color image can be obtained without providing a color filter in the imaging element.

Further, the driving of the light source device11203may be controlled to change the intensity of output light at predetermined time intervals. The driving of the imaging element of the camera head11102is controlled in synchronization with the timing of the change in the light intensity to acquire an image in a time-division manner, and the image is synthesized, whereby it is possible to generate a so-called image in a high dynamic range without underexposure or overexposure.

Further, the light source device11203may be configured to be able to supply light having a predetermined wavelength band corresponding to special light observation. In the special light observation, for example, by emitting light in a band narrower than that of irradiation light (that is, white light) during normal observation using wavelength dependence of light absorption in a body tissue, so-called narrow band light observation (narrow band imaging) in which a predetermined tissue such as a blood vessel in the mucous membrane surface layer is imaged with a high contrast is performed. Alternatively, in the special light observation, fluorescence observation in which an image is obtained by fluorescence generated by emitting excitation light may be performed. The fluorescence observation can be performed by emitting excitation light to a body tissue, and observing fluorescence from the body tissue (autofluorescence observation), or locally injecting a reagent such as indocyanine green (ICG) to a body tissue, and emitting excitation light corresponding to a fluorescence wavelength of the reagent to the body tissue to obtain a fluorescence image. The light source device11203can supply narrow band light and/or excitation light corresponding to such special light observation.

FIG.17is a block diagram illustrating an example of functional configurations of the camera head11102and the CCU11201illustrated inFIG.16.

The camera head11102includes a lens unit11401, an imaging unit11402, a driving unit11403, a communication unit11404, and a camera head control unit11405. The CCU11201includes a communication unit11411, an image processing unit11412, and a control unit11413. The camera head11102and the CCU11201are connected to each other via a transmission cable11400so that they can communicate with each other.

The lens unit11401is an optical system provided at a portion for connection to the lens barrel11101. Observation light taken from the tip of the lens barrel11101is guided to the camera head11102and is incident on the lens unit11401. The lens unit11401is constituted by a combination of a plurality of lenses including a zoom lens and a focus lens.

The imaging unit11402is constituted by an imaging element. The imaging element constituting the imaging unit11402may be one element (so-called single plate type) or a plurality of elements (so-called multi-plate type). When the imaging unit11402is configured as a multi-plate type, for example, image signals corresponding to RGB are generated by the imaging elements, and a color image may be obtained by synthesizing the image signals. Alternatively, the imaging unit11402may be configured to include a pair of imaging elements for acquiring image signals for the right eye and the left eye corresponding to three-dimensional (3D) display. When 3D display is performed, the surgeon11131can ascertain the depth of biological tissues in the surgical part more accurately. Here, when the imaging unit11402is configured as a multi-plate type, a plurality of lens units11401may be provided according to the imaging elements.

Further, the imaging unit11402may not be necessarily provided in the camera head11102. For example, the imaging unit11402may be provided inside the lens barrel11101, immediately after the objective lens.

The driving unit11403is constituted by an actuator, and moves the zoom lens and the focus lens of the lens unit11401by a predetermined distance along an optical axis under the control of the camera head control unit11405. Thereby, the magnification and the focus of the image captured by the imaging unit11402can be appropriately adjusted.

The communication unit11404is constituted by a communication device for transmitting or receiving various pieces of information to or from the CCU11201. The communication unit11404transmits the image signal obtained from the imaging unit11402as RAW data to the CCU11201via the transmission cable11400.

The communication unit11404also receives a control signal for controlling the driving of the camera head11102from the CCU11201and supplies the control signal to the camera head control unit11405. The control signal includes information related to imaging conditions, for example, information specifying a frame rate of a captured image, information specifying an exposure value during imaging, and/or information specifying a magnification and a focus of a captured image.

Note that the imaging conditions such as the frame rate, the exposure value, the magnification, and the focus may be appropriately designated by the user, or may be automatically set by the control unit11413of the CCU11201on the basis of the acquired image signal. In the latter case, a so-called auto exposure (AE) function, an auto focus (AF) function, and an auto white balance (AWB) function are provided in the endoscope11100.

The camera head control unit11405controls the driving of the camera head11102on the basis of the control signal from the CCU11201received via the communication unit11404.

The communication unit11411is constituted by a communication device for transmitting and receiving various pieces of information to and from the camera head11102. The communication unit11411receives the image signal transmitted from the camera head11102via the transmission cable11400.

In addition, the communication unit11411transmits a control signal for controlling the driving of the camera head11102to the camera head11102. The image signal and the control signal can be transmitted through telecommunication, optical communication or the like.

The image processing unit11412performs various image processing on the image signal which is the RAW data transmitted from the camera head11102.

The control unit11413performs various controls regarding imaging of the surgical part or the like using the endoscope11100and the display of a captured image obtained by imaging the surgical part or the like. For example, the control unit11413generates a control signal for controlling the driving of the camera head11102.

Further, the control unit11413causes the display device11202to display the captured image obtained by imaging the surgical part or the like on the basis of the image signal subjected to image processing by the image processing unit11412. In this case, the control unit11413may recognize various objects in the captured image using various image recognition technologies. For example, the control unit11413can recognize surgical tools such as forceps, specific biological parts, bleeding, mist when the energy treatment tool11112is used, and the like by detecting the edge shape, color, and the like of the object included in the captured image. When the control unit11413causes the display device11202to display the captured image, it may cause various types of surgical support information to be superimposed and displayed with the image of the surgical part using the recognition result. When the surgical support information is displayed in an overlapping manner and is presented to the surgeon11131, it is possible to reduce the burden on the surgeon11131, and the surgeon11131can reliably proceed with the surgery.

The transmission cable11400that connects the camera head11102to the CCU11201is an electrical signal cable compatible with communication of an electrical signal, an optical fiber compatible with optical communication, or a composite cable thereof.

Here, in the example illustrated in the drawing, wired communication is performed using the transmission cable11400, but the communication between the camera head11102and the CCU11201may be performed wirelessly.

The example of the endoscopic surgery system to which the technology according to the present disclosure can be applied has been described above. The technology according to the present disclosure can be applied to the endoscope11100, (the imaging unit11402of) the camera head11102, or the like among the configurations described above. Specifically, the solid-state imaging device according to the present technology can be applied to the imaging unit10402. By applying the technology according to the present disclosure to the endoscope11100, (the imaging unit11402of) the camera head11102, or the like, it is possible to improve the performance of the endoscope11100, (the imaging unit11402of) the camera head11102, or the like.

While the endoscopic surgery system has been described here as an example, the technology according to the present disclosure may be applied to other systems, for example, a microscopic surgery system.

12. Example of Application to Moving Body

The technology according to the present disclosure (the present technology) can be applied to various products. For example, the technology of the present disclosure may be implemented as a device mounted in any type of moving body such as an automobile, an electric automobile, a motorbike, a hybrid electric automobile, a bicycle, a personal mobility, an airplane, a drone, a ship, and a robot.

FIG.18is a block diagram showing a schematic configuration example of a vehicle control system that is an example of a moving body control system to which the technology according to the present disclosure can be applied.

A vehicle control system12000includes a plurality of electronic control units connected to each other through a communication network12001. In an example illustrated inFIG.18, the vehicle control system12000includes a drive system control unit12010, a body system control unit12020, a vehicle exterior information detection unit12030, a vehicle interior information detection unit12040, and an integrated control unit12050. In addition, as the functional configuration of the integrated control unit12050, a microcomputer12051, an audio/image output unit12052, and an in-vehicle network interface (I/F)12053are illustrated in the drawing.

The drive system control unit12010controls operations of devices related to a drive system of a vehicle according to various programs. For example, the drive system control unit12010functions as a control device for a driving force generating device for generating a driving force of a vehicle such as an internal combustion engine or a drive motor, a driving force transmission mechanism for transmitting a driving force to wheels, a steering mechanism for adjusting a steering angle of a vehicle, and a braking device for generating a braking force of a vehicle.

The body system control unit12020controls operations of various devices mounted in the vehicle body according to various programs. For example, the body system control unit12020functions as a control device such as a keyless entry system, a smart key system, a power window device, or various lamps such as a headlamp, a back lamp, a brake lamp, a turn signal and a fog lamp. In this case, radio waves transmitted from a portable device that substitutes for a key or signals of various switches may be input to the body system control unit12020. The body system control unit12020receives inputs of the radio waves or signals, and controls a door lock device, a power window device, and a lamp of the vehicle.

The vehicle exterior information detection unit12030detects information outside the vehicle in which the vehicle control system12000is mounted. For example, an imaging unit12031is connected to the vehicle exterior information detection unit12030. The vehicle exterior information detection unit12030causes the imaging unit12031to capture an image of the outside of the vehicle and receives the captured image. The vehicle exterior information detection unit12030may perform object detection processing or distance detection processing for peoples, cars, obstacles, signs, and letters on the road based on the received image.

The imaging unit12031is an optical sensor that receives light and outputs an electrical signal according to the intensity of the light received. The imaging unit12031can output an electrical signal as an image or output it as a distance measurement information. The light received by the imaging unit12031may be visible light or invisible light such as infrared light.

The vehicle interior information detection unit12040detects information on the interior of the vehicle. In the vehicle interior information detection unit12040, for example, a driver status detection unit12041that detects the recognition of a driver's conditions is connected. The driver status detection unit12041includes, for example, a camera that images the driver, and the vehicle interior information detection unit12040may calculate the degree of fatigue or degree of concentration of the driver based on detection information input from the driver status detection unit12041, and may determine whether the driver is asleep.

The microcomputer12051can calculate a control target value of the driving force generation device, the steering mechanism, or the braking device on the basis of the information inside and outside the vehicle acquired by the vehicle exterior information detection unit12030or the vehicle interior information detection unit12040, and output a control command to the drive system control unit12010. For example, the microcomputer12051can perform coordinated control for realizing an advanced driver assistance system (ADAS) function including vehicle collision avoidance, shock alleviation, following travel based on an inter-vehicle distance, vehicle speed maintenance travel, a vehicle collision warning, or a vehicle lane deviation warning.

Further, the microcomputer12051can perform coordinated control for the purpose of automated driving or the like in which autonomous travel is performed without depending on an operation of a driver by controlling the driving force generator, the steering mechanism, the braking device, and the like on the basis of information regarding the vicinity of the vehicle acquired by the vehicle exterior information detection unit12030or the vehicle interior information detection unit12040.

In addition, the microcomputer12051can output a control command to the body system control unit12020based on the information outside the vehicle acquired by the vehicle exterior information detection unit12030. For example, the microcomputer12051can control a head lamp in accordance with a position of a front vehicle or an oncoming vehicle detected by the vehicle exterior information detection unit12030and can perform cooperated control in order to achieve antiglare such as switching of a high beam to a low beam.

The audio/image output unit12052transmits an output signal of at least one of audio and an image to an output device capable of visually or audibly notifying an occupant of a vehicle or the outside of the vehicle of information. In the example illustrated inFIG.18, as such an output device, an audio speaker12061, a display unit12062and an instrument panel12063are illustrated. The display unit12062may include, for example, at least one of an onboard display and a head-up display.

FIG.19is a diagram illustrating an example of positions at which the imaging unit12031is installed.

The imaging units12101,12102,12103,12104, and12105may be provided at positions such as a front nose, side-view mirrors, a rear bumper, a back door, and an upper part of a windshield in a vehicle interior of the vehicle12100, for example. The imaging unit12101provided on a front nose and the imaging unit12105provided in an upper portion of the vehicle interior front glass mainly acquire images of a side in front of the vehicle12100. The imaging units12102and12103provided on the side mirrors mainly acquire images of sides of the vehicle12100. The imaging unit12104provided on the rear bumper or the back door mainly acquires images of a side behind the vehicle12100. The images of a front side which are acquired by the imaging units12101and12105are mainly used for detection of preceding vehicles, pedestrians, obstacles, traffic signals, traffic signs, lanes, and the like.

FIG.19illustrates an example of imaging ranges of the imaging units12101to12104. An imaging range12111is an imaging range of the imaging unit12101provided on the front nose, imaging ranges12112and12113are imaging ranges of the imaging units12102and12103provided in the side mirrors, and an imaging range12114is an imaging range of the imaging unit12104provided in the rear bumper or the back door. For example, by superimposing image data captured by the imaging units12101to12104, it is possible to obtain a bird's-eye view image viewed from the upper side of the vehicle12100.

For example, the microcomputer12051can extract, particularly, a closest three-dimensional object on a path through which the vehicle12100is traveling, which is a three-dimensional object traveling at a predetermined speed (for example, 0 km/h or higher) in the substantially same direction as the vehicle12100, as a preceding vehicle by acquiring a distance to each of three-dimensional objects in the imaging ranges12111to12114and temporal change in the distance(a relative speed with respect to the vehicle12100) on the basis of distance information obtained from the imaging units12101to12104. Further, the microcomputer12051can set an inter-vehicle distance which should be guaranteed in advance in front of a preceding vehicle and can perform automated brake control(also including following stop control) or automated acceleration control(also including following start control). In this way, it is possible to perform cooperated control in order to perform automated driving or the like in which a vehicle autonomously travels irrespective of a manipulation of a driver.

For example, the microcomputer12051can classify and extract three-dimensional object data regarding three-dimensional objects into two-wheeled vehicles, ordinary vehicles, large vehicles, pedestrians, and other three-dimensional objects such as utility poles on the basis of distance information obtained from the imaging units12101to12104and use the three-dimensional object data for automatic avoidance of obstacles. For example, the microcomputer12051identifies surrounding obstacles of the vehicle12100as obstacles which can be viewed by the driver of the vehicle12100and obstacles which are difficult to view. Then, the microcomputer12051determines a collision risk indicating the degree of risk of collision with each obstacle, and when the collision risk is equal to or higher than the set value and there is a possibility of collision, an alarm is output to the driver through the audio speaker12061and the display unit12062, forced deceleration and avoidance steering are performed through the drive system control unit12010, and thus it is possible to perform driving support for collision avoidance.

At least one of the imaging units12101to12104may be an infrared camera that detects infrared light. For example, the microcomputer12051can recognize a pedestrian by determining whether there is a pedestrian in the captured image of the imaging units12101to12104. Such pedestrian recognition is performed by, for example, a procedure in which feature points in the captured images of the imaging units12101to12104as infrared cameras are extracted and a procedure in which pattern matching processing is performed on a series of feature points indicating the outline of the object and it is determined whether the object is a pedestrian.

When the microcomputer12051determines that there is a pedestrian in the captured images of the imaging units12101to12104, and the pedestrian is recognized, the audio/image output unit12052controls the display unit12062so that the recognized pedestrian is superimposed and displayed with a square contour line for emphasis. In addition, the audio/image output unit12052may control the display unit12062so that an icon or the like indicating a pedestrian is displayed at a desired position.

An example of the vehicle control system to which the technology according to the present disclosure (the present technology) can be applied has been described above. The technology according to the present disclosure may be applied, for example, to the imaging unit12031and the like among the configurations described above. Specifically, the solid-state imaging device according to the present technology can be applied to the imaging unit12031. By applying the technology according to the present disclosure to the imaging unit12031, it is possible to improve the performance of the imaging unit12031.

Note that the present technology are not limited to the above-described embodiments, usage examples, and application examples, and various changes can be made without departing from the gist of the present technology.

Furthermore, the effects described in the present specification are merely exemplary and not intended to be limiting, and other effects may be provided as well.

In addition, the present technology can also adopt the following configurations.

a pixel region in which a plurality of pixels are two-dimensionally disposed, wherein each of the pixels includes a photoelectric conversion unit and a concavo-convex portion, the photoelectric conversion unit photoelectrically converting incident light formed on a semiconductor substrate, and the concavo-convex portion being positioned above the photoelectric conversion unit and formed on a light receiving surface side of the semiconductor substrate, and

the number of irregularities of a concavo-convex portion included in a pixel disposed in a central portion of the pixel region and the number of irregularities of a concavo-convex portion included in a pixel disposed in a peripheral portion of the pixel region are different from each other.

[2] The solid-state imaging device according to [1],

wherein the number of irregularities of the concavo-convex portion included in the pixel disposed in the central portion of the pixel region is smaller than the number of irregularities of the concavo-convex portion included in the pixel disposed in the peripheral portion of the pixel region.

[3] The solid-state imaging device according to [1] or [2],

wherein the number of irregularities of the concavo-convex portion included in each pixel constituting the plurality of pixels changes from the pixel disposed in the central portion of the pixel region to the pixel disposed in the peripheral portion of the pixel region.

wherein the number of irregularities of the concavo-convex portion included in each pixel constituting the plurality of pixels gradually increases from the pixel disposed in the central portion of the pixel region to the pixel disposed in the peripheral portion of the pixel region.

wherein a pitch of a convex portion constituting the concavo-convex portion included in the pixel disposed in the central portion of the pixel region and a pitch of a convex portion constituting the concavo-convex portion included in the pixel disposed in the peripheral portion of the pixel region are different from each other.

wherein a pitch of a convex portion constituting the concavo-convex portion included in the pixel disposed in the central portion of the pixel region is larger than a pitch of a convex portion constituting the concavo-convex portion included in the pixel disposed in the peripheral portion of the pixel region.

wherein a pitch of a convex portion constituting the concavo-convex portion included in the pixel disposed in the central portion of the pixel region is larger than a pitch of a convex portion constituting the concavo-convex portion included in the pixel disposed in the peripheral portion of the pixel region,

the concavo-convex portion included in the pixel disposed in the central portion of the pixel region is provided in an entire inner surface of the pixel when the pixel is seen in plan view, and

the concavo-convex portion included in the pixel disposed in the peripheral portion of the pixel region is provided in an entire inner surface of the pixel when the pixel is seen in plan view.

wherein the concavo-convex portion included in the pixel disposed in the central portion of the pixel region has a point-symmetrical shape with a center of the concavo-convex portion as a point of symmetry when seen in plan view and has a rectangular shape, and

the concavo-convex portion included in the pixel disposed in the peripheral portion of the pixel region has a point-symmetrical shape with a center of the concavo-convex portion as a point of symmetry when seen in plan view and has a rectangular shape.

wherein the concavo-convex portion included in the pixel disposed in the central portion of the pixel region has a point-symmetrical shape with a center of the concavo-convex portion as a point of symmetry when seen in plan view and has a rectangular shape, and

the concavo-convex portion included in the pixel disposed in the peripheral portion of the pixel region has a point-symmetrical shape with a center of the concavo-convex portion as a point of symmetry when seen in plan view and has a polygonal shape.

wherein the concavo-convex portion included in each pixel constituting the plurality of pixels is provided to cover a light converging region in which the incident light formed in the photoelectric conversion unit converges.

wherein a position at which the concavo-convex portion included in the pixel disposed in the central portion of the pixel region is provided in the pixel when the pixel is seen in plan view is different from a position at which the concavo-convex portion included in the pixel disposed in the peripheral portion of the pixel region is provided in the pixel when the pixel is seen in plan view.

[12] The solid-state imaging device according to [11],

wherein the concavo-convex portion included in the pixel disposed in the central portion of the pixel region is provided at least in a center portion in the pixel when the pixel is seen in plan view, and

the concavo-convex portion included in the pixel disposed in the peripheral portion of the pixel region is provided to extend at least from the center portion in the pixel toward a peripheral portion without reaching a boundary portion between the pixel and an adjacent pixel when the pixel is seen in plan view.

[13] The solid-state imaging device according to [11] or [12],

wherein the concavo-convex portion included in the pixel disposed in the central portion of the pixel region is provided at least in a center portion in the pixel when the pixel is seen in plan view, and

a concavo-convex portion included in a pixel disposed in a right peripheral portion in the pixel region when the pixel region is seen in plan view is provided to extend at least from the center portion in the pixel toward a left peripheral portion without reaching a boundary portion between the pixel and an adjacent pixel when the pixel is seen in plan view.

[14] The solid-state imaging device according to any one of [11] to [13],

wherein the concavo-convex portion included in the pixel disposed in the central portion of the pixel region is provided at least in a center portion in the pixel when the pixel is seen in plan view, and

a concavo-convex portion included in a pixel disposed in a left peripheral portion in the pixel region when the pixel region is seen in plan view is provided to extend at least from the center portion in the pixel toward a right peripheral portion without reaching a boundary portion between the pixel and an adjacent pixel when the pixel is seen in plan view.

a pixel region in which a plurality of pixels are two-dimensionally disposed, wherein each of the pixels includes a photoelectric conversion unit and a concavo-convex portion, the photoelectric conversion unit photoelectrically converting incident light formed on a semiconductor substrate, and the concavo-convex portion being positioned above the photoelectric conversion unit and formed on a light receiving surface side of the semiconductor substrate, and

a position at which the concavo-convex portion included in the pixel disposed in the central portion of the pixel region is provided in the pixel when the pixel is seen in plan view is different from a position at which the concavo-convex portion included in the pixel disposed in the peripheral portion of the pixel region is provided in the pixel when the pixel is seen in plan view.

[16] The solid-state imaging device according to [15],

wherein the concavo-convex portion included in the pixel disposed in the central portion of the pixel region is provided at least in a center portion in the pixel when the pixel is seen in plan view, and

the concavo-convex portion included in the pixel disposed in the peripheral portion of the pixel region is provided to extend at least from the center portion in the pixel toward a peripheral portion without reaching a boundary portion between the pixel and an adjacent pixel when the pixel is seen in plan view.

[17] The solid-state imaging device according to [15] or [16],

wherein the concavo-convex portion included in the pixel disposed in the central portion of the pixel region is provided at least in a center portion in the pixel when the pixel is seen in plan view, and

a concavo-convex portion included in a pixel disposed in a right peripheral portion in the pixel region when the pixel region is seen in plan view is provided to extend at least from the center portion in the pixel toward a left peripheral portion without reaching a boundary portion between the pixel and an adjacent pixel when the pixel is seen in plan view.

[18] The solid-state imaging device according to any one of [15] to [17],

wherein the concavo-convex portion included in the pixel disposed in the central portion of the pixel region is provided at least in a center portion in the pixel when the pixel is seen in plan view, and

a concavo-convex portion included in a pixel disposed in a left peripheral portion in the pixel region when the pixel region is seen in plan view is provided to extend at least from the center portion in the pixel toward a right peripheral portion without reaching a boundary portion between the pixel and an adjacent pixel when the pixel is seen in plan view.

[19] Electronic equipment on which the solid-state imaging device according to any one of [1] to [18] is mounted.

REFERENCE NUMERALS LIST

2(2-1G,2-2R) Color filter

5(5-1,5-2,5-3) Light shielding film

1001a,1001b,1001c,1002a,1002b,1002c,1003a,1004a,1004b,1004c,1005a,1005b,1005c,1007a,1007b,1007c,1008a,1009a,1009b,1009c,1010a,1010b,1010c,1011a,1012aRegion of four pixels of solid-state imaging device