Patent Publication Number: US-2016233268-A1

Title: Manufacturing method of photoelectric conversion apparatus

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This is a continuation application of U.S. patent application Ser. No. 14/629,071, filed on Feb. 23, 2015, which claims a priority to Japanese Patent Application No. 2014-038188 filed on Feb. 28, 2014 which is hereby expressly incorporated by reference in its entirety. 
    
    
     BACKGROUND 
     1. Technical Field 
     Several aspects of the present invention relate to a photoelectric conversion apparatus, a manufacturing method of the photoelectric conversion apparatus, and an electronic device. 
     2. Related Art 
     Heretofore, photoelectric conversion apparatuses that are provided with a switching element realized by a thin film transistor that is formed on a substrate and a photoelectric conversion part consisting of a semiconductor film having a chalcopyrite structure that is connected to the switching element are known. 
     A compound semiconductor thin film that is constituted to include group 11 elements, group 13 elements and group 16 elements is used for the semiconductor film having a chalcopyrite structure. The photoelectric conversion part is constituted by forming this compound semiconductor thin film into a p-type semiconductor film, and forming a p-n junction with an n-type semiconductor film. 
     In the above 11-13-16 group compound semiconductor, a CuInSe 2  film (so-called CIS film) including copper (Cu), indium (In) and selenium (Se), or a Cu(In,Ga)Se 2  film (so-called CIGS film) including Cu, In, gallium (Ga) and Se is used. The CIS film is formed by annealing a metal film including Cu and In in a Se atmosphere at about 500° C. The CIGS film is similarly formed by annealing a metal film including Cu, In and Ga in a Se atmosphere. 
     For example, JP-A-2012-169517 (FIG. 3) discloses an image sensor serving as a photoelectric conversion apparatus in which thin film transistors and the like are formed on a substrate as a circuit part, and photoelectric conversion parts using the abovementioned CIGS film are laminated on the circuit part. 
     However, there is a problem with the photoelectric conversion apparatus disclosed in JP-A-2012-169517 in that a desired image cannot be obtained due to stray light. 
     More specifically, with the photoelectric conversion apparatus disclosed in JP-A-2012-169517, when light is incident on the photoelectric conversion apparatus, leakage current flows in the thin film transistors of the circuit part upon light (stray light) being incident on the thin film transistors, causing the circuit to malfunction, and thus a desired image cannot be obtained. In view of this, a shading film is formed by covering the thin film transistors with a metal film, in order to prevent stray light from being incident on the thin film transistors. However, there is a problem in using a metal film as the shading film for preventing stray light from being incident on the thin film transistors. When a metal film is used as the shading film, much of the light incident on the shading film is reflected. The light reflected by the shading film becomes stray light, and is incident on the photoelectric conversion parts directly or after being multiply reflected. When light is incident on photoelectric conversion parts that are at different locations from the photoelectric conversion part on which the light was originally supposed to be incident, the circuit malfunctions, and a desired image cannot be obtained. In view of this, a photoelectric conversion apparatus that is able to obtain desired images is desired. 
     SUMMARY 
     Advantages of some aspects of the invention can be realized as the following illustrative embodiments or aspects. 
     A method of manufacturing a photoelectric conversion apparatus according to one aspect includes forming a switching element on one surface of a substrate, forming an interlayer insulation film so as to cover the switching element, forming a shading film on the interlayer insulation film in an area overlapping the switching element when seen from a film thickness direction of the substrate, forming a lower electrode on the interlayer insulation film, and forming a semiconductor film having a chalcopyrite structure on the lower electrode. A group 16 element is included in the semiconductor film, and in forming the semiconductor film, the shading film and the lower electrode are caused to react to the group 16 element to form a shading film including the group 16 element and a lower electrode including the group 16 element. 
     According to this aspect, the group 16 element that is included in the semiconductor film having a chalcopyrite structure is also included in the shading film and the lower electrode. Including the group 16 element in the lower electrode facilitates ohmic contact between the lower electrode and the semiconductor film, and improves the electrical characteristics of the photoelectric conversion apparatus. The shading film prevents light from being incident on the switching element, while including the group 16 element in the shading film lowers the reflectance of the shading film compared with a metal film. Therefore, because light that is reflected by the shading film is reduced, light that is incident on photoelectric conversion parts that are at different locations from the photoelectric conversion part on which light was originally supposed to be incident is reduced. As a result, a photoelectric conversion apparatus that is able to obtain desired images can be provided. 
     In the method of manufacturing a photoelectric conversion apparatus according to the above aspect, preferably the group 16 element includes at least one of selenium and sulfur. 
     According to this aspect, a semiconductor film having a chalcopyrite structure that is able to realize high photoelectric conversion efficiency can be obtained. 
     In the method of manufacturing a photoelectric conversion apparatus according to the above aspect, preferably the shading film and the lower electrode include molybdenum. 
     According to this aspect, ohmic contact between the lower electrode and the semiconductor film is facilitated, and the electrical characteristics of the photoelectric conversion apparatus improve. Furthermore, a lower electrode having low electrical resistance can be obtained at low cost. Also, MoSe 2  or MoS 2  will be included in the shading film. MoSe 2  is a semiconductor having a band gap width of about 1.35 to 1.41 eV, and MoS 2  is a semiconductor having a band gap width of about 1.8 eV. Therefore, the shading film absorbs light having energy greater than or equal to the band gap width, and the reflectance of the shading film decreases. Thus, because light that is reflected by the shading film is reduced, light that is incident on photoelectric conversion parts that are at different locations from the photoelectric conversion part on which light was originally supposed to be incident is reduced. As a result, a photoelectric conversion apparatus that is able to obtain desired images can be provided. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The invention will be described with reference to the accompanying drawings, wherein like numbers reference like elements. 
         FIGS. 1A and 1B  relate to Embodiment 1, with  FIG. 1A  being a schematic connection diagram of an image sensor serving as a photoelectric conversion apparatus, and  FIG. 1B  being an equivalent circuit diagram of a photo sensor serving as a photoelectric conversion element. 
         FIG. 2  is a schematic partial plan view showing the arrangement of photo sensors in an image sensor according to Embodiment 1. 
         FIG. 3  is a schematic cross-sectional view of a photo sensor cut at an A-A′ line in  FIG. 2  according Embodiment 1. 
         FIGS. 4A to 4D  are schematic partial cross-sectional views showing a method of manufacturing a photoelectric conversion apparatus according to Embodiment 1. 
         FIG. 5  is a schematic cross-sectional view of a photo sensor cut at an A-A′ line in  FIG. 2  according to Embodiment 2. 
         FIGS. 6A to 6E  are schematic partial cross-sectional views showing a method of manufacturing a photoelectric conversion apparatus according to Embodiment 2. 
         FIG. 7A  is a schematic perspective view showing a biometric authentication apparatus serving as an electronic device, and  FIG. 7B  is a schematic cross-sectional view of the biometric authentication apparatus serving as an electronic device. 
     
    
    
     DESCRIPTION OF EXEMPLARY EMBODIMENTS 
     Hereinafter, embodiments of the invention will be described with reference to the drawings. Note that, in the following diagrams, the scale of the layers and members is differentiated from the actual scale, in order to facilitate recognition of the individual layers and members. Note also that, in the following illustrative embodiments, the phrase “on the substrate”, for example, is intended to represent cases where a constituent part or the like is disposed on the substrate in contact therewith, is disposed on the substrate via another constituent part, or is disposed on the substrate partially in contact therewith and partially via another constituent part. 
     Embodiment 1 
     Photoelectric Conversion Apparatus 
     First, an image sensor serving as a photoelectric conversion apparatus of Embodiment 1 will be described with reference to  FIGS. 1 to 3 . 
       FIG. 1A  is a schematic connection diagram showing an electrical configuration of an image sensor serving as a photoelectric conversion apparatus, and  FIG. 1B  is an equivalent circuit diagram of a photo sensor serving as a photoelectric conversion element.  FIG. 2  is a schematic partial plan view showing the arrangement of the photo sensors in the image sensor, and  FIG. 3  is a schematic cross-sectional view showing the structure of the photo sensor cut at an A-A′ line in  FIG. 2 . 
     As shown in  FIG. 1A , an image sensor  100  serving as a photoelectric conversion apparatus of the present embodiment has a plurality of scan lines  3   a  and a plurality of data lines  6  that extend and intersect each other in an element region F. The image sensor  100  also has a scan line circuit  102  to which the plurality of scan lines  3   a  are electrically connected and a data line circuit  101  to which the plurality of data lines  6  are electrically connected. The image sensor  100  further has a plurality of photo sensors  50  serving as photoelectric conversion elements that are provided corresponding to the vicinity of the intersections of the scan lines  3   a  and the data lines  6 , and are disposed in a matrix in the element region F. 
     As shown in  FIG. 1B , the photo sensors  50  serving as photoelectric conversion elements are constituted to include a thin film transistor (TFT)  10  serving as a switching element, a photodiode  20  serving as a photoelectric conversion part, and a storage capacitor  30 . A gate electrode of the TFT  10  is connected to the scan line  3   a , and a source electrode of the TFT  10  is connected to the data line  6 . One end of the photodiode  20  serving as a photoelectric conversion part is connected to a drain electrode of the TFT  10 , and the other end is connected to a constant potential line  12  provided in parallel with the data line  6 . One electrode of the storage capacitor  30  is connected to the drain electrode of the TFT  10 , and the other electrode is connected to a constant potential line  3   b  provided in parallel with the scan line  3   a.    
     As shown in  FIG. 2 , the photo sensors  50  serving as photoelectric conversion elements are provided in areas planarly partitioned by the scan lines  3   a  and the data lines  6 , and are constituted to include the TFT  10  and the photodiode  20  serving as a photoelectric conversion part. The storage capacitor  30  is not illustrated in  FIG. 2 . 
     As shown in  FIG. 3 , the photo sensors  50  serving as photoelectric conversion elements are formed on a substrate  1  of transparent glass, opaque silicon or the like, for example. 
     On the substrate  1 , a base insulation film  1   a  of silicon oxide (SiO 2 ) is formed so as to cover the surface of the substrate  1 , and an island-like semiconductor film  2  of polycrystalline silicon having a film thickness of about 50 nm, for example, is formed on the base insulation film  1   a . Furthermore, a gate insulation film  3  is formed using an insulating material such as SiO 2  having a film thickness of about 100 nm, for example, to cover the semiconductor film  2 . Note that, the gate insulation film  3  also covers the base insulation film  1   a  as well as covering the semiconductor film  2 . 
     A gate electrode  3   g  is formed on the gate insulation film  3  in a position opposing a channel forming region  2   c  of the semiconductor film  2 . The gate electrode  3   g  is electrically connected to a scan line  3   a  shown in  FIG. 2 , and is formed using a metal material such as molybdenum (Mo) having a film thickness of about 500 nm, for example. 
     A first interlayer insulation film  4  is formed using SiO 2  having a film thickness of about 800 nm to cover the gate electrode  3   g  and the gate insulation film  3 . Contact holes  4   a  and  4   b  are formed in portions of the gate insulation film  3  and the first interlayer insulation film  4  that cover a drain region  2   d  and a source region  2   s  of the semiconductor film  2 . A conductive film made of a metal material such as Mo having a film thickness of about 500 nm, for example, is formed so as to cover the first interlayer insulation film  4  and fill contact holes  4   a  and  4   b , and a drain electrode  5   d , a source electrode  5   s  and a data line  6  are formed by patterning this conductive film. The source electrode  5   s  is connected to the source region  2   s  of the semiconductor film  2  through the contact hole  4   a , and is also connected to the data line  6 . The drain electrode  5   d  is connected to the drain region  2   d  of the semiconductor film  2  through the contact hole  4   b . The TFT  10  is formed with the drain region  2   d , the channel forming region  2   c , the source region  2   s , and the like. 
     A second interlayer insulation film  7  serving as an interlayer insulation film is formed to cover the drain electrode  5   d , the source electrode  5   s , the data line  6 , and the first interlayer insulation film  4 . The second interlayer insulation film  7  is formed using silicon nitride (Si 3 N 4 ) having a film thickness of about 800 nm. 
     On the second interlayer insulation film  7 , a lower electrode  8  of the photodiode  20  serving as a photoelectric conversion part is formed. The lower electrode  8  is formed with an island-like conductive film  8   a  made of Mo having a film thickness of about 500 nm, and a semiconductor film  8   b  made of MoSe 2  having a film thickness of about 100 nm that is formed on the conductive film  8   a  and includes the group 16 element selenium (Se). The lower electrode  8  is electrically connected to the drain electrode  5   d  through a contact hole  7   a  formed in the second interlayer insulation film. 
     An island-like shading film  9  is formed on the second interlayer insulation film  7  in an area overlapping the TFT  10  when seen from the thickness direction (film thickness direction) of the films that are formed on the substrate (hereinafter, also referred to as “in plan view”). More specifically, the shading film  9  is formed in an area overlapping the semiconductor film  2  when seen from the film thickness direction of the substrate (in plan view of the substrate). This shading film  9  prevents light from being incident on the TFT  10 , and, in particular, prevents light from being incident on the semiconductor film  2 . The shading film  9 , similarly to the lower electrode  8 , is formed with an island-like conductive film  9   a  made of Mo having a film thickness of about 500 nm, and a semiconductor film  9   b  made of MoSe 2  having a film thickness of about 100 nm that is formed on the conductive film  9   a  and includes the group 16 element selenium (Se). 
     On the lower electrode  8 , a semiconductor film  21  having a chalcopyrite structure consisting of a CIS film or a CIGS film having a film thickness of about 1 μm is formed. 
     A third interlayer insulation film  11  is formed so as to cover the second interlayer insulation film  7 , the lower electrode  8 , the shading film  9 , and the semiconductor film  21  having a chalcopyrite structure. The third interlayer insulation film  11  is formed using Si 3 N 4  having a film thickness of about 500 nm. 
     An island-like buffer layer  22  is formed so as to connect to the semiconductor film  21  having a chalcopyrite structure through a contact hole  11   a  formed in the third interlayer insulation film  11 . The buffer layer  22  is formed with a cadmium sulfide (CdS) film having a film thickness of about 50 nm. Zinc oxide (ZnO), zinc sulfide (ZnS) or the like may be used instead of CdS. 
     A transparent electrode  23  is formed on the third interlayer insulation film  11  and the buffer layer  22 . The transparent electrode  23  consists of a transparent conductive film of ITO (indium tin oxide), IZO (indium zinc oxide) or the like with a film thickness of about 100 nm, for example. The transparent electrode  23  doubles as the constant potential line  12  shown in  FIG. 1B . 
     The photodiode  20  serving as a photoelectric conversion part is constituted by the lower electrode  8 , the semiconductor film  21  having a chalcopyrite structure, the buffer layer  22 , and the transparent electrode  23 . 
     In the present embodiment, the circuit part provided on the substrate  1  includes the scan lines  3   a , the data lines  6 , the constant potential lines  3   b  and  12 , the TFTs  10  and the storage capacitors  30  connected to these interconnects, the data line circuit  101 , and the scan line circuit  102  shown in  FIGS. 1A and 1B . Note that, the data line circuit  101  to which the data lines  6  are connected and the scan line circuit  102  to which the scan lines  3   a  are connected can also be respectively attached separately to the substrate  1  as integrated circuits. 
     According to such an image sensor  100  serving as a photoelectric conversion apparatus, when light is incident on the photodiode  20  serving as a photoelectric conversion part in a state where a reverse bias is applied to the photodiode  20  using the constant potential lines  3   b  and  12 , photoelectric current flows in the photodiode  20 , and electric charge accumulates in the storage capacitor  30  according to the amount of photoelectric current. 
     Also, signals corresponding to the electric charge accumulated in the storage capacitors  30  that are provided in the respective photo sensors  50  are sequentially output to the data lines  6  by turning on (selecting) a plurality of TFTs  10  using each of the plurality of scan lines  3   a . Accordingly, the intensity of light received by each photo sensor  50  in the element region F can be respectively detected. 
     Manufacturing Method of Photoelectric Conversion Apparatus 
     A method of manufacturing an image sensor serving as a photoelectric conversion apparatus of Embodiment 1 will be described using  FIGS. 3 and 4 .  FIGS. 4A to 4D  are schematic partial cross-sectional views showing a manufacturing method of an image sensor serving as a photoelectric conversion apparatus, and are schematic cross-sectional views showing the manufacturing method on the second interlayer insulation film  7 . 
     As shown in  FIG. 3 , the manufacturing method of the image sensor  100  serving as a photoelectric conversion apparatus involves firstly forming the SiO 2  base insulation film  1   a  using chemical vapor deposition (CVD) or the like on the substrate  1  of transparent glass, opaque silicon or the like. Next, an amorphous silicon film having a film thickness of about 50 nm is formed by CVD or the like on the base insulation film  1   a . The amorphous silicon film is crystallized by laser crystallization or the like to form a polycrystalline silicon film. Thereafter, the island-like semiconductor film  2 , which is a polycrystalline silicon film, is formed by photolithography or the like. 
     Next, SiO 2  having a film thickness of about 100 nm is formed by CVD or the like so as to cover the semiconductor film  2  and the base insulation film  1   a , thus forming the gate insulation film  3 . A Mo film having a film thickness of about 500 nm is formed on the gate insulation film  3  by sputtering or the like, and the island-like gate electrode  3   g  is formed by photolithography. Impurity ions are implanted into the semiconductor film  2  by ion implantation to form the source region  2   s , the drain region  2   d , and the channel forming region  2   c . An SiO 2  film having a film thickness of about 800 nm is formed so as to cover the gate insulation film  3  and the gate electrode  3   g , thus forming the first interlayer insulation film  4 . 
     Next, the contact holes  4   a  and  4   b  that reach the source region  2   s  and the drain region  2   d  are formed in the first interlayer insulation film  4 . Thereafter, a Mo film having a film thickness of about 500 nm is formed by sputtering or the like on the first interlayer insulation film  4  and in the contact holes  4   a  and  4   b  and patterned by photolithography to form the source electrode  5   s , the drain electrode  5   d , and the data line  6 . The TFT  10  is formed by the above processes. 
     An Si 3 N 4  film having a film thickness of about 800 nm is formed so as to cover the first interlayer insulation film  4 , the source electrode  5   s , the drain electrode  5   d , and the data line  6 , thus forming the second interlayer insulation film  7 . 
     The contact hole  7   a  that reaches the drain electrode  5   d  is formed in the second interlayer insulation film  7 . Thereafter, as shown in  FIG. 4A , a Mo film  89   a  having a film thickness of about 500 nm is formed as a conductive film by sputtering or the like on the second interlayer insulation film  7  and in the contact hole  7   a . Thereafter, a Cu—Ga alloy film  21   a  and an In film  21   b  are formed by sputtering or the like on the Mo film  89   a . The Cu—Ga alloy film  21   a  and the In film  21   b  are precursor films that will form the semiconductor film  21  having a chalcopyrite structure by subsequent selenization annealing. The total film thickness of the precursor films is about 500 nm. 
     The selenization annealing process will be described with reference to  FIG. 4B . After the processes of  FIG. 4A  are completed, this substrate is subject to selenization annealing such that the Cu—Ga alloy film  21   a  and the In film  21   b , which are precursor films, form the semiconductor film (CIGS film)  21  having a chalcopyrite structure. Selenization annealing is annealing performed at a temperature of about 500° C. in an atmosphere including hydrogen selenide (H 2 Se) gas. When selenization annealing is performed, the surface of the Mo film  89   a  is selenized and a MoSe 2  film  89   b  is formed. The film thickness of the MoSe 2  film  89   b  is about 100 nm. Accordingly, the semiconductor film  21  and the MoSe 2  film  89   b  are films including the group 16 element Se. 
     As shown in  FIG. 4C , the semiconductor film  21  having a chalcopyrite structure is patterned by photolithography. 
     As shown in  FIG. 4D , the MoSe 2  film  89   b  and the Mo film  89   a  are patterned by photolithography to form the lower electrode  8  and the shading film  9 . 
     Next, as shown in  FIG. 3 , an Si 3 N 4  film having a film thickness of about 500 nm is formed so as to cover the semiconductor film  21 , the lower electrode  8 , the shading film  9  and the second interlayer insulation film  7 , thus forming the third interlayer insulation film  11 . The contact hole  11   a  that reaches the semiconductor film  21  is formed in the third interlayer insulation film  11 . Thereafter, a CdS film having a film thickness of about 50 nm is formed by CBD (chemical bath deposition) or the like on the third interlayer insulation film  11  and in the contact hole  11   a  and patterned by photolithography to form the buffer layer  22 . An ITO film having a film thickness of about 100 nm is formed by sputtering or the like on the third interlayer insulation film  11  and the buffer layer  22 , and is patterned by photolithography to form the transparent electrode  23 . 
     The photoelectric conversion apparatus of Embodiment 1 is formed in this manner. 
     According to abovementioned Embodiment 1, the following effects can be obtained. 
     In the image sensor serving as such a photoelectric conversion apparatus, the shading film  9  is formed for preventing light from being incident on the TFT  10 , and is constituted by the conductive film  9   a  made of Mo and the semiconductor film  9   b  made of MoSe 2 . Because the semiconductor film  9   b  is a semiconductor having a band gap width of about 1.35 to 1.41 eV, the semiconductor film  9   b  absorbs light having energy greater than or equal to the band gap width, and the reflectance of the shading film decreases. Thus, because light that is reflected by the shading film is reduced by also forming the semiconductor film including group 16 elements rather than forming the shading film with only a metal material, light that is incident on photoelectric conversion parts that are at different locations from the photodiode  20  on which light was originally supposed to be incident is reduced. As a result, an image sensor serving as a photoelectric conversion apparatus that is able to obtain desired images can be provided. 
     Selenium is included in the semiconductor film  21 . The semiconductor film  21  can thereby be configured to have a chalcopyrite structure that is able to realize high photoelectric conversion efficiency. 
     Molybdenum (Mo) is included in the lower electrode  8  and the shading film  9 . The ohmic contact between the lower electrode  8  and the semiconductor film  21  is thereby facilitated, and the electrical characteristics of the photo sensors  50  installed in the image sensor  100  improve. Furthermore, a lower electrode  8  having low electrical resistance can be obtained at low cost. Also, molybdenum selenide (MoSe 2 ) will be included in the shading film  9 . Accordingly, light that is reflected by the shading film  9  can be reduced. 
     Embodiment 2 
     Photoelectric Conversion Apparatus 
     An image sensor serving as a photoelectric conversion apparatus of Embodiment 2 will be described with reference to  FIGS. 1, 2 and 5 .  FIG. 5  is a schematic cross-sectional view showing the structure of a photo sensor cut at an A-A′ line in  FIG. 2  according to Embodiment 2. Note that the same numerals are used for constituent parts that are the same as Embodiment 1, and redundant description will be omitted. 
     Embodiment 2 differs from Embodiment 1 in the structure of the lower electrode  8  and the shading film  9 , with these constituent parts being referred to as a lower electrode  80  and a shading film  90  in the description of Embodiment 2. As shown in  FIG. 5 , in an image sensor  51  of Embodiment 2, the lower electrode  80  of the photodiode  20  is formed on the second interlayer insulation film  7 . The lower electrode  80  is formed with the island-like conductive film  8   a  made of Mo having a film thickness of about 500 nm, and a semiconductor film  80   b  made of MoSe 2  having a film thickness of about 100 nm that is formed on the upper surface and lateral surfaces of the conductive film  8   a  and includes the group 16 element Se. 
     The island-like shading film  90  is formed on the second interlayer insulation film  7  in an area overlapping the TFT  10  when seen from the film thickness direction of the substrate (in plan view of the substrate). More specifically, the shading film  90  is formed in an area overlapping the semiconductor film  2  when seen from the film thickness direction of the substrate. This shading film  90  prevents light from being incident on the TFT  10 , and, in particular, prevents light from being incident on the semiconductor film  2 . The shading film  90 , similarly to the lower electrode  80 , is formed with the island-like conductive film  9   a  made of Mo having a film thickness of about 500 nm, and a semiconductor film  90   b  made of Mo Se 2  having a film thickness of about 100 nm that is formed on the upper surface and lateral surfaces of the conductive film  9   a  and includes the group 16 element Se. Apart from the structure of the lower electrode  80  and the shading film  90 , Embodiment 2 is the same as Embodiment 1. 
     Manufacturing Method of Photoelectric Conversion Apparatus 
     The manufacturing method of an image sensor serving as a photoelectric conversion apparatus of Embodiment 2 will be described using  FIGS. 5 and 6 . 
       FIGS. 6A to 6E  are schematic partial cross-sectional views showing a manufacturing method of an image sensor serving as a photoelectric conversion apparatus, and are schematic cross-sectional views showing the manufacturing method on the second interlayer insulation film  7 . Embodiment 2 differs from Embodiment 1 in the structure of the lower electrode  80  and the shading film  90 . Since the processes up to forming the second interlayer insulation film  7  are the same as Embodiment 1, description thereof will be omitted. 
     As shown in  FIG. 6A , the Mo film  89   a  having a film thickness of about 500 nm is formed as a conductive film by sputtering or the like on the second interlayer insulation film  7  and in the contact hole  7   a.    
     As shown in  FIG. 6B , the Mo film  89   a  is patterned by photolithography to form the conductive film  8   a  made of Mo that will form part of the lower electrode  80  and the conductive film  9   a  made of Mo that will form part of the shading film  90 . 
     As shown in  FIG. 6C , the Cu—Ga alloy film  21   a  and the In film  21   b  are formed by sputtering or the like, so as to cover the second interlayer insulation film  7 , the conductive film  8   a  and the conductive film  9   a . The Cu—Ga alloy film  21   a  and the In film  21   b  are precursor films that will form the semiconductor film  21  having a chalcopyrite structure by subsequent selenization annealing. The total film thickness of the precursor films is about 500 nm. 
     The selenization annealing process will be described with reference to  FIG. 6D . After the processes of  FIG. 6C  are completed, this substrate is subject to selenization annealing such that the Cu—Ga alloy film  21   a  and the In film  21   b , which are precursor films, form the semiconductor film  21  having a chalcopyrite structure. Selenization annealing is annealing performed at a temperature of about 500° C. in an atmosphere including H 2 Se gas. When selenization annealing is performed, the upper surface and the lateral surfaces of the conductive film  8   a  and the conductive film  9   a  are selenized and the semiconductor films  80   b  and  90   b  made of MoSe 2  are formed. The film thickness of the semiconductor films  80   b  and  90   b  is about 100 nm. The lower electrode  80  and the shading film  90  in which the semiconductor films  80   b  and  90   b  made of MoSe 2  are provided on the upper surface and the lateral surfaces of the conductive films  8   a  and  9   a  made of Mo are formed in this manner. As shown in  FIG. 6E , the semiconductor film  21  having a chalcopyrite structure is patterned by photolithography. The subsequent processes are the same as Embodiment 1. The photoelectric conversion apparatus of Embodiment 2 is formed in this manner. 
     According to abovementioned Embodiment 2, the following effects can be obtained. 
     In such an image sensor serving as a photoelectric conversion apparatus, the shading film  90  is formed for preventing light from being incident on the TFT  10 , and is constituted by the conductive film  9   a  and the semiconductor film  90   b . In Embodiment 2, the semiconductor film  90   b  is not only formed on the upper surface of the conductive film  9   a  but also on the lateral surfaces. Because the semiconductor film  90   b  is a semiconductor having a band gap width of about 1.35 to 1.41 eV, the semiconductor film  90   b  absorbs light having energy greater than or equal to the band gap width, and the reflectance of the upper surface and the lateral surfaces of the shading film  90  decreases. Thus, because light that is reflected by the shading film  90  is reduced by also forming the semiconductor film  90   b  including group 16 elements rather than forming the shading film  90  with only a metal material, light that is incident on photoelectric conversion parts that are at different locations from the photoelectric conversion part on which light was originally supposed to be incident is reduced. In Embodiment 2, because the upper surface and lateral surfaces of the shading film  90  are constituted by the semiconductor film  90   b  including group 16 elements, reflection of light by the shading film  90  is reduced compared with Embodiment 1. As a result, an image sensor serving as a photoelectric conversion apparatus that is able to obtain desired images can be provided. 
     Embodiment 3 
     Biometric Authentication Apparatus 
     Next, a biometric authentication apparatus serving as an electronic device of the present embodiment will be described with reference to  FIGS. 7A and 7B . FIG.  7 A is a schematic perspective view showing the biometric authentication apparatus, and  FIG. 7B  is a schematic cross-sectional view. 
     As shown in  FIGS. 7A and 7B , a biometric authentication apparatus  500  serving as an electronic device of the present embodiment is an apparatus that identifies and authenticates a person whose finger is held up to the biometric authentication apparatus  500 , by optically detecting (imaging) the vein pattern of the finger, and comparing the detected vein pattern with the vein pattern of each person who has been registered. Specifically, the biometric authentication apparatus  500  is provided with a subject receiving part  502  having a groove for placing a finger that is held up to the biometric authentication apparatus  500  in a predetermined location, an imaging part  504  to which the image sensor  100  serving as a photoelectric conversion apparatus of the above embodiment is attached, and a micro lens array  503  disposed between the subject receiving part  502  and the imaging part  504 . 
     A plurality of light sources  501  are built into the subject receiving part  502  so as to be disposed on both sides along the groove. In order to image the vein pattern without being affected by outside light, light emitting diodes (LED), EL elements or the like, for example, that emit near-infrared light other than visible light are used for the light sources  501 . The vein pattern in the finger is illuminated by the light sources  501 , and the image light thereof is focused towards the image sensor  100  by micro lenses  503   a  provided in the micro lens array  503 . The micro lens  503   a  may be provided in correspondence with each photo sensor  50  of the image sensor  100 , or may be provided so as to be paired with a plurality of photo sensors  50 . 
     Note that an optical compensation plate that compensates for luminance unevenness in the light illuminated by the plurality of light sources  501  may be provided between the subject receiving part  502  incorporating the light sources  501  and the micro lens array  503 . According to such a biometric authentication apparatus  500 , the image sensor  100  which receives near-infrared light and is capable of accurately outputting the illuminated vein pattern as an image pattern is provided, enabling a living body (human body) to be reliably authenticated. 
     The image sensor  100  of Embodiment 1 or the image sensor  51  of Embodiment 2 is used for the image sensor  100 . Accordingly, the biometric authentication apparatus  500  is an apparatus in which the image sensor  100  is able to obtain desired images. 
     Note that the invention is not limited to the abovementioned embodiments, and it is possible to apply various changes, improvements and the like to the abovementioned embodiments. Modifications are described below. 
     Modification 1 
     In the image sensor  100  and the image sensor  51  of the above embodiments, the electrical configuration of the photo sensor  50  and connection thereof are not limited thereto. For example, the electrical output from the photodiode  20  may be connected to the gate electrode  3   g  of the TFT  10 , and received light may be detected as the change in voltage or current between the source electrode  5   s  and the drain electrode  5   d.    
     Modification 2 
     In the image sensor  100  of the above embodiments, the group 16 element that is included in the semiconductor film  21  having a chalcopyrite structure, the shading films  9  and  90 , and the lower electrodes  8  and  80  is given as selenium (Se), but is not necessarily limited to Se. For example, the group 16 element may be sulfur (S), the semiconductor film having a chalcopyrite structure may be a CIS film, and the shading film may be constituted by a Mo film and a MoS 2  film. Also, the two group 16 elements Se and S may be included in the semiconductor film having a chalcopyrite structure, the shading film, and the lower electrode. Alternatively, tellurium may be used as the group 16 element. 
     A semiconductor film having a chalcopyrite structure that is able to realize high photoelectric conversion efficiency can also be obtained at this time. Molybdenum sulfide (MoS 2 ) is a semiconductor having a band gap width of about 1.8 eV. Therefore, the shading film absorbs light having energy greater than or equal to the band gap width, and the reflectance of the shading film decreases. Thus, because light that is reflected by the shading film is reduced, light that is incident on photoelectric conversion parts that are at different locations from the photoelectric conversion part on which light was originally supposed to be incident is reduced. As a result, a photoelectric conversion apparatus that is able to obtain desired images can be provided. 
     Modification 3 
     In the method of manufacturing the photoelectric conversion apparatus of the above embodiments, the precursor films are given as the Cu—Ga alloy film  21   a  and the In film  21   b , but are not limited thereto. For example, a Cu film may be formed instead of a Cu—Ga alloy film. In this case, the semiconductor film having a chalcopyrite structure will be a CIS film. Also, the order in which the films are formed may be changed, with the Cu—Ga alloy film or the Cu film being formed after forming the In film. Furthermore, the number of layers may be increased, and multiple layers of the Cu—Ga alloy film and the In film may be formed. Also, rather than laminating films, a Cu—In—Ga alloy film or a Cu—In alloy film may be formed. 
     Modification 4 
     The electronic device to which the image sensor  100  of the above embodiments is mounted is not limited to the biometric authentication apparatus  500 . For example, the image sensor  100  can also be applied to a solid-state imaging apparatus that images fingerprints or the iris of the eye.