Imaging device and electronic device

Abstract

Provided is an image-capturing device and an electronic apparatus that can suppress performance degradation caused by charge accumulation. The image-capturing device comprises: a photoelectric conversion layer having a first surface and a second surface disposed on the opposite side from the first surface; a first electrode disposed near the first surface; and a second electrode disposed near the second surface. Assuming that a region superimposed on the first electrode is a first region and a region placed out of the first electrode is a second region in the thickness direction of the photoelectric conversion layer, the first thickness of the photoelectric conversion layer in at least a part of the first region is smaller than the second thickness of the photoelectric conversion layer in the second region.

Description

Technical Field

[0001] The present disclosure relates to an imaging device and an electronic device.

Background Art

[0002] A structure is known in which a light shielding layer is provided on a photoelectric conversion layer on a floating diffusion (hereinafter, FD) electrode so as not to generate charges on the FD electrode (see, for example, FIGS. 41 to 44 of Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] When light is obliquely incident on the surface of the photoelectric conversion layer, light may also be obliquely incident on the photoelectric conversion layer on the FD electrode covered with the light shielding layer, and charges may be generated and accumulated. When the absorption coefficient of the material constituting the photoelectric conversion layer is small, the photoelectric conversion layer may be thickened to increase the absorption rate. However, when the photoelectric conversion layer is thickened, the generation of charges due to obliquely incident light becomes more prominent. When charges are accumulated in the photoelectric conversion layer on the FD electrode, GS (Global Shutter) driving may be inhibited.

[0005] The present disclosure has been made in view of such circumstances, and an object thereof is to provide an imaging device and an electronic device capable of suppressing a performance degradation due to charge accumulation.

Means for Solving the Problems

[0006] An imaging device according to an aspect of the present disclosure includes a photoelectric conversion layer having a first surface and a second surface located on the opposite side of the first surface, a first electrode located on the first surface side, and a second electrode located on the second surface side. In the thickness direction of the photoelectric conversion layer, when a region overlapping with the first electrode is defined as a first region and a region deviating from the first electrode is defined as a second region, a first film thickness of the photoelectric conversion layer in at least a part of the first region is thinner than a second film thickness of the photoelectric conversion layer in the second region. According to this, the imaging device can suppress photoelectric conversion and charge accumulation above the first electrode. The imaging device can suppress a performance degradation caused by charge accumulation above the first electrode.

Brief Description of the Drawings

[0007]

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[0008] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. In the description of the drawings referred to below, the same or similar parts are denoted by the same or similar reference numerals. However, it should be noted that the drawings are schematic, and the relationship between the thickness and the planar dimensions, the ratio of the thicknesses of the respective layers, etc. are different from the actual ones. Therefore, specific thicknesses and dimensions should be determined in consideration of the following description. Of course, there are also portions where the dimensional relationships and ratios are different between the drawings.

[0009] In the following description, the definitions of directions such as up and down are merely for convenience of explanation and do not limit the technical idea of the present disclosure. For example, if the object is rotated by 90° and observed, up and down are read as left and right, and if it is rotated by 180° and observed, up and down are read in reverse.

[0010] In the following description, the directions may be described using the terms in the X-axis direction, the Y-axis direction, and the Z-axis direction. For example, the Z-axis direction is the thickness direction of the photoelectric conversion layer 15 described later. The X-axis direction and the Y-axis direction are directions orthogonal to the Z-axis direction. The X-axis direction, the Y-axis direction, and the Z-axis direction are orthogonal to each other. In the following description, a direction parallel to the X-axis direction and the Y-axis direction is also referred to as a horizontal direction.

[0011] <Embodiment 1> (Overall Structure) FIG. 1 is a cross-sectional view schematically showing a configuration example of an imaging device 100 according to Embodiment 1 of the present disclosure. FIG. 2 is a circuit diagram schematically showing a configuration example of the imaging device 100 according to Embodiment 1 of the present disclosure. The imaging device 100 according to Embodiment 1 is, for example, a back-illuminated stacked solid-state imaging device. The imaging device 100 includes, for example, a green pixel device sensitive to green light, a blue pixel device sensitive to blue light, and a red pixel device sensitive to red light.

[0012] For example, the red pixel device and the blue pixel device are provided in a semiconductor substrate 70. The blue pixel device is located closer to the light incident side than the red pixel device. Further, the green pixel device is provided above the blue pixel device. One pixel is constituted by the green pixel device, the blue pixel device, and the red pixel device. A color filter is not provided.

[0013] The green pixel device includes a photoelectric conversion unit PD1 in which a first electrode 11, a photoelectric conversion layer 15, and a second electrode 16 are stacked. The photoelectric conversion unit PD1 further includes a third electrode 12 that is disposed apart from the first electrode 11 and that is disposed to face the photoelectric conversion layer 15 via an insulating layer 82. The third electrode 12 is an electrode for charge storage. The photoelectric conversion unit PD1 is disposed above the semiconductor substrate 70.

[0014] The first electrode 11 and the third electrode 12 are formed separately from each other on an interlayer insulating film 81. The interlayer insulating film 81 and the third electrode 12 are covered with an insulating layer 82. The insulating layer 82 is an example of the "second insulating layer" of the present disclosure. A photoelectric conversion layer 15 is formed on the insulating layer 82, and a second electrode 16 is formed on the photoelectric conversion layer 15. In the thickness direction (for example, the Z-axis direction) of the photoelectric conversion layer 15, the third electrode 12 overlaps the photoelectric conversion layer 15. An insulating layer 83 is formed on the entire surface including the second electrode 16. An on-chip micro lens 90 is provided on the insulating layer 83.

[0015] The first electrode 11, the second electrode 16, and the third electrode 12 are each composed of a light-transmissive conductive film. As the light-transmissive conductive film, ITO (indium tin oxide) is exemplified.

[0016] The photoelectric conversion layer 15 is composed of a layer containing at least an organic photoelectric conversion material having sensitivity to green light. Examples of the organic photoelectric conversion material having sensitivity to green light include rhodamine-based dyes, merocyanine-based dyes, quinacridone derivatives, subphthalocyanine-based dyes (subphthalocyanine derivatives), and the like.

[0017] Alternatively, the photoelectric conversion layer 15 may be composed of an inorganic material. Examples of the inorganic material (hereinafter referred to as inorganic photoelectric conversion material) constituting the photoelectric conversion layer 15 include crystalline silicon, amorphous silicon, microcrystalline silicon, crystalline selenium, amorphous selenium, and chalcopyrite-based compounds such as CIGS (CuInGaSe), CIS (CuInSe2), CuInS2, CuAlS2, CuAlSe2, CuGaS2, CuGaSe2, AgAlS2, AgAlSe2, AgInS2, AgInSe2, or III-V group compounds such as GaAs, InP, AlGaAs, InGaP, AlGaInP, InGaAsP, and further, compound semiconductors such as CdSe, CdS, In2Se3, In2S3, Bi2Se3, Bi2S3, ZnSe, ZnS, PbSe, PbS. In addition, it is also possible to use quantum dots made of these materials in the photoelectric conversion layer.

[0018] The interlayer insulating film 81, the insulating layers 82, and 83 are composed of well-known insulating materials (for example, SiO2 and SiN).

[0019] The imaging device 100 is provided on the semiconductor substrate 70 and further includes a control unit having a drive circuit to which the first electrode 11 is connected. The light incident surface of the semiconductor substrate 70 is upward, and the opposite side of the semiconductor substrate 70 is downward. A wiring layer 62 composed of a plurality of wirings is provided below the semiconductor substrate 70.

[0020] The third electrode 12 is connected to the drive circuit. For example, the third electrode 12 is connected to the drive circuit via a connection hole 66, a pad portion 64, and a wiring VOA provided in the interlayer insulating film 81. The size of the third electrode 12 is larger than that of the first electrode 11.

[0021] An element isolation region 71 and an oxide film 72 are formed on the surface (front surface) 70A side of the semiconductor substrate 70. Further, on the surface 70A side of the semiconductor substrate 70, a reset transistor TR1rst, an amplification transistor TR1amp, a selection transistor TR1sel, and a first floating diffusion layer FD1 that constitute a control unit of the green pixel device are provided. The reset transistor TR1rst, the amplification transistor TR1amp, and the selection transistor TR1sel constitute a drive circuit.

[0022] The reset transistor TR1rst is composed of a gate portion 51, a channel formation region 51A, a drain region 51B, and a source region 51C. The gate portion 51 of the reset transistor TR1rst is connected to a reset line. The source region 51C of the reset transistor TR1rst also serves as the first floating diffusion layer FD1. The drain region 51B is connected to the power supply VDD.

[0023] The first electrode 11 is connected to the source region 51C (first floating diffusion layer FD1) of the reset transistor TR1rst via a connection hole 65, a pad portion 63, the semiconductor substrate 70, a contact hole portion 61 formed in the interlayer insulating film 76, and a wiring layer 62 formed in the interlayer insulating film 76 provided in the interlayer insulating film 81.

[0024] The amplification transistor TR1amp is composed of a gate portion 52, a channel formation region 52A, a drain region 52B, and a source region 52C. The gate portion 52 is connected to the first electrode 11 and the source region 51C (first floating diffusion layer FD1) of the reset transistor TR1rst via the wiring layer 62. Also, the drain region 52B shares a region with the drain region 51B of the reset transistor TR1rst and is connected to the power supply VDD.

[0025] The selection transistor TR1sel is composed of a gate portion 53, a channel formation region 53A, a drain region 53B, and a source region 53C. The gate portion 53 is connected to a selection line. Also, the drain region 53B shares a region with the source region 52C of the amplification transistor TR1amp. The source region 53C is connected to a signal line (data output line) VSL1.

[0026] The blue pixel device includes an n-type semiconductor region 41 provided on a semiconductor substrate 70 as a photoelectric conversion layer of a photoelectric conversion unit PD2. A gate portion 45 of a transfer transistor TR2trs composed of a vertical transistor extends to the n-type semiconductor region 41 and is connected to a transfer gate line TG2. Also, a second floating diffusion layer FD2 is provided in a region 45C of the semiconductor substrate 70 near the gate portion 45 of the transfer transistor TR2trs. The charge accumulated in the n-type semiconductor region 41 is read out to the second floating diffusion layer FD2 through a transfer channel formed along the gate portion 45.

[0027] In the blue pixel device, further, a reset transistor TR2rst, an amplification transistor TR2amp, and a selection transistor TR2sel that constitute a control unit of the blue pixel device are provided on the surface 70A side of the semiconductor substrate 70.

[0028] The reset transistor TR2rst is composed of a gate portion, a channel formation region, a drain region, and a source region. The gate portion of the reset transistor TR2rst is connected to a reset line. The drain region of the reset transistor TR2rst is connected to a power supply VDD. The source region of the reset transistor TR2rst also serves as the second floating diffusion layer FD2.

[0029] The amplification transistor TR2amp is composed of a gate portion, a channel formation region, a drain region, and a source region. The gate portion of the amplification transistor TR2amp is connected to the source region (the second floating diffusion layer FD2) of the reset transistor TR2rst. Also, the drain region of the amplification transistor TR2amp shares a region with the drain region of the reset transistor TR2rst and is connected to the power supply VDD.

[0030] The selection transistor TR2sel is composed of a gate portion, a channel formation region, a drain region, and a source region. The gate portion of the selection transistor TR2sel is connected to the selection line. Also, the drain region of the selection transistor TR2sel shares a region with the source region of the amplification transistor TR2amp. The source region of the selection transistor TR2sel is connected to the signal line (data output line) VSL2.

[0031] The red pixel device includes an n-type semiconductor region 43 provided in the semiconductor substrate 70 as a photoelectric conversion layer of the photoelectric conversion unit PD3. The gate portion 46 of the transfer transistor TR3trs is connected to the transfer gate line TG3. Also, a third floating diffusion layer FD3 is provided in a region 46C of the semiconductor substrate 70 near the gate portion 46 of the transfer transistor TR3trs. The charges accumulated in the n-type semiconductor region 43 are read out to the third floating diffusion layer FD3 through a transfer channel 46A formed along the gate portion 46.

[0032] In the red pixel device, further, a reset transistor TR3rst, an amplification transistor TR3amp, and a selection transistor TR3sel that constitute a control unit of the red pixel device are provided on the surface 70A side of the semiconductor substrate 70.

[0033] The reset transistor TR3rst is composed of a gate portion, a channel formation region, a drain region, and a source region. The gate portion of the reset transistor TR3rst is connected to the reset line. The drain region of the reset transistor TR3rst is connected to the power supply VDD. The source region of the reset transistor TR3rst also serves as the third floating diffusion layer FD3.

[0034] The amplification transistor TR3amp is composed of a gate portion, a channel formation region, a drain region, and a source region. The gate portion of the amplification transistor TR3amp is connected to the source region (the third floating diffusion layer FD3) of the reset transistor TR3rst. Also, the drain region of the amplification transistor TR3amp shares a region with the drain region of the reset transistor TR3rst and is connected to the power supply VDD.

[0035] The selection transistor TR3sel is composed of a gate portion, a channel formation region, a drain region, and a source region. The gate portion of the selection transistor TR3sel is connected to the selection line. Also, the drain region of the selection transistor TR3sel shares a region with the source region of the amplification transistor TR3amp. The source region of the selection transistor TR3sel is connected to the signal line (data output line) VSL3.

[0036] A p + layer 44 is provided between the surface 70A of the n-type semiconductor region 43 and the semiconductor substrate 70, suppressing the generation of dark current. A p + layer 42 is formed between the n-type semiconductor region 41 and the n-type semiconductor region 43. A part of the side surface of the n-type semiconductor region 43 is surrounded by the p + layer 42. On the back surface 70B side of the semiconductor substrate 70, a p + layer 73 is formed. From the p + layer 73 to inside the contact hole portion 61, an HfO2 film 74 and an insulating film 75 are formed. In the interlayer insulating film 76, wirings (not shown) are formed across a plurality of layers.

[0037] (Structure of the photoelectric conversion unit and its peripheral part) FIG. 3 is a cross-sectional view schematically showing a configuration example of a photoelectric conversion unit PD1 of an imaging device 100 according to Embodiment 1 of the present disclosure and its peripheral part. In FIG. 3, a first electrode 11, a third electrode 12, and an insulating layer 82 are provided on an interlayer insulating film 81 (see FIG. 1). The first electrode 11 is an electrode connected to a floating diffusion (for example, the first floating diffusion layer FD1 shown in FIG. 1) provided on a semiconductor substrate 70 (see FIG. 1). The third electrode 12 is covered with the insulating layer 82. Further, a through hole 82H is provided in the insulating layer 82. The through hole 82H is located on the first electrode 11.

[0038] As shown in FIG. 3, a conductive layer 14 is provided on the insulating layer 82. The conductive layer 14 has, for example, a semiconductor layer 141 and a buffer layer 142 laminated on the semiconductor layer 141. The semiconductor layer 141 is a layer having a function of charge accumulation and transfer. The semiconductor layer 141 is in contact with the first electrode 11. The buffer layer 142 is in contact with the photoelectric conversion layer 15. A photoelectric conversion layer 15 and an insulating layer 83 are provided on the buffer layer 142.

[0039] The semiconductor layer 141 is made of a semiconductor material having a large bandgap value (for example, a bandgap value of 3.0 eV or more) and a higher mobility than the material constituting the photoelectric conversion layer 15. Examples of such semiconductor materials include oxide semiconductor materials such as IGZO; transition metal dichalcogenides; silicon carbide; diamond; graphene; carbon nanotubes; and organic semiconductor materials such as condensed polycyclic hydrocarbon compounds and condensed heterocyclic compounds.

[0040] When the charge to be accumulated is an electron, the semiconductor layer 141 may be made of a material having an ionization potential larger than the ionization potential of the material constituting the photoelectric conversion layer 15. Further, when the charge to be accumulated is a hole, the semiconductor layer 141 may be made of a material having an electron affinity smaller than the electron affinity of the material constituting the photoelectric conversion layer 15.

[0041] The impurity concentration in the semiconductor layer 141 is preferably 1×10 18 cm -3 or less. The semiconductor layer 141 may have a single-layer structure or a multilayer structure.

[0042] The buffer layer 142 has at least one of a function of smoothly transferring electrons from the photoelectric conversion layer 15 to the semiconductor layer 141 and a function of blocking holes from the semiconductor layer 141.

[0043] By providing the semiconductor layer 141 and the buffer layer 142 between the first electrode 11 and the photoelectric conversion layer 15, recombination during charge accumulation can be prevented, and the transfer efficiency of the charges accumulated in the photoelectric conversion layer 15 to the first electrode 11 can be increased. Also, the generation of dark current can be suppressed.

[0044] The photoelectric conversion layer 15 has a first surface 15A and a second surface 15B located on the side opposite to the first surface 15A. The first surface 15A is in contact with the buffer layer 142, and the second surface is in contact with the second electrode 16. As shown in FIG. 3, in the thickness direction (for example, the Z-axis direction) of the photoelectric conversion layer 15, the region overlapping the first electrode 11 is defined as a first region R1, and the region deviated from the first electrode 11 (that is, the non-overlapping region) is defined as R2. The film thickness T1 (an example of the "first film thickness" in the present disclosure) of the photoelectric conversion layer 15 in at least a part of the first region R1 is thinner than the film thickness T2 (an example of the "second film thickness" in the present disclosure) of the photoelectric conversion layer 15 in the second region R2. For example, the film thickness T1 is zero.

[0045] In this example, in at least a part of the region overlapping the first electrode 11 in the Z-axis direction (above the first electrode 11 in FIG. 3), the photoelectric conversion layer 15 is not provided. As shown in FIG. 3, above the first electrode 11, through holes 15H provided in the photoelectric conversion layer 15 are arranged.

[0046] The insulating layer 83 has a first insulating film 831 and a second insulating film 832 laminated on the first insulating film 831. The first insulating film 831 is an example of the "first insulating layer" of the present disclosure. The first insulating film 831 is disposed in the first region R1. For example, the first insulating film 831 is disposed in a through hole 15H provided in the photoelectric conversion layer 15. The first insulating film 831 is in contact with the photoelectric conversion layer 15 in the horizontal direction.

[0047] The second electrode 16 is provided in the first region R1. The second insulating film 832 covers the first insulating film 831 and the second electrode 16. Further, a through hole 83H is provided in the second insulating film 832. A wiring 17 is provided on the second insulating film 832. The wiring 17 is connected to the second electrode 16 through the through hole 83H.

[0048] (Manufacturing method) The imaging device 100 is manufactured using various devices such as a film forming device (including a CVD (Chemical Vapor Deposition) device and a sputtering device), an exposure device, an etching device, an ion implantation device, a heat treatment device, a CMP (Chemical Mechanical Polishing) device, and a bonding device. Hereinafter, these devices are collectively referred to as manufacturing devices. The photoelectric conversion unit PD1 shown in FIG. 3 and its peripheral portion can be manufactured by the manufacturing method 1 or the manufacturing method 2 described below.

[0049] (Manufacturing method 1) FIGS. 4A to 4I are cross-sectional views showing the manufacturing method 1 of the imaging device 100 according to Embodiment 1 of the present disclosure in the order of steps. In FIG. 4A, the manufacturing device forms a first electrode 11 and a third electrode 12 on an interlayer insulating film 81 (see FIG. 1). Next, the manufacturing device forms an insulating layer 82 on the interlayer insulating film 81 on which the first electrode 11 and the third electrode 12 are formed. Next, the manufacturing device locally etches the insulating layer 82 to form a through hole 82H.

[0050] Next, the manufacturing apparatus forms a conductive layer (semiconductor layer before patterning) on the insulating layer 82 in which the through hole 82H is formed. Next, the manufacturing apparatus patterns the conductive layer into a predetermined shape using photolithography technology and etching technology. Thereby, the semiconductor layer 141 is formed from the conductive layer.

[0051] Next, the manufacturing apparatus forms a conductive layer (buffer layer before patterning) on the semiconductor layer 141. Next, the manufacturing apparatus patterns the conductive layer into a predetermined shape using photolithography technology and etching technology. Thereby, as shown in FIG. 4B, the buffer layer 142 is formed from the conductive layer. Next, as shown in FIG. 4C, the manufacturing apparatus forms the first insulating film 831 on the buffer layer 142.

[0052] Next, as shown in FIG. 4D, the manufacturing apparatus patterns the first insulating film 831 into a predetermined shape using photolithography technology and etching technology. In this step, the manufacturing apparatus leaves the first insulating film 831 above the first electrode 11 and removes the first insulating film 831 from other regions. In this step, the buffer layer 142 under the first insulating film 831 functions as an etching stopper for the first insulating film 831.

[0053] Next, as shown in FIG. 4E, the manufacturing apparatus forms the photoelectric conversion layer 15 on the buffer layer 142. In this step, the manufacturing apparatus forms the photoelectric conversion layer 15 thicker than the first insulating film 831. Thereby, the upper surface and the side surface of the first insulating film 831 are covered with the photoelectric conversion layer 15.

[0054] Next, as shown in FIG. 4F, the manufacturing apparatus forms the second electrode 16 on the photoelectric conversion layer 15. Next, as shown in FIG. 4G, the manufacturing apparatus patterns the second electrode 16 and the photoelectric conversion layer 15 using photolithography technology and etching technology.

[0055] Next, as shown in FIG. 4H, the manufacturing apparatus forms a second insulating film 832 so as to cover the second electrode 16 and the first insulating film 831 exposed from below the second electrode 16. The second insulating film 832 is laminated on the first insulating film 831 to obtain an insulating layer 83.

[0056] Next, as shown in FIG. 4I, the manufacturing apparatus forms a through-hole 83H in the second insulating film 832 using photolithography technology and etching technology. Next, the manufacturing apparatus forms a conductive layer on the second insulating film 832 in which the through-hole 83H is formed. Next, the manufacturing apparatus patterns the conductive layer using photolithography technology and etching technology. Thereby, a wiring 17 connected to the second electrode 16 through the through-hole 83H is formed. Through the above steps, the imaging device 100 shown in FIG. 3 is completed.

[0057] In the above manufacturing method 1, since the photoelectric conversion layer 15 is self-alignedly formed by the first insulating film 831, the etching damage to the photoelectric conversion layer 15 is small.

[0058] (Manufacturing Method 2) FIGS. 5A to 5F are cross-sectional views showing the manufacturing method 2 of the imaging device 100 according to Embodiment 1 of the present disclosure in the order of steps. In FIG. 5A, up to the step of forming the buffer layer 142, it is the same as the manufacturing method 1 described with reference to FIGS. 4A to 4I.

[0059] After the buffer layer 142 is formed, as shown in FIG. 5B, the manufacturing apparatus forms a photoelectric conversion layer 15 on the buffer layer 142. Next, as shown in FIG. 5C, the manufacturing apparatus forms a light-transmissive second electrode 16 on the photoelectric conversion layer 15. Next, as shown in FIG. 5D, the manufacturing apparatus patterns the second electrode 16 and the photoelectric conversion layer 15 using photolithography technology and etching technology.

[0060] Next, as shown in FIG. 5E, the manufacturing apparatus forms an insulating layer 83 on the buffer layer 142 on which the photoelectric conversion layer 15 and the second electrode 16 are formed. The through-hole 15H is filled by the insulating layer 83.

[0061] The subsequent steps are the same as those in Manufacturing Method 1. As shown in FIG. 5F, the manufacturing apparatus forms a through hole 83H in the insulating layer 83 using photolithography technology and etching technology. Next, the manufacturing apparatus forms a conductive layer on the insulating layer 83 in which the through hole 83H is formed, and patterns the conductive layer to form the wiring 17. Through the above steps, the imaging device 100 shown in FIG. 3 is completed.

[0062] In the above Manufacturing Method 2, the photoelectric conversion layer 15 is formed before the insulating layer 83 is formed. The film formation surface (substrate) of the photoelectric conversion layer 15 is flatter than that in Manufacturing Method 1 by the amount of the absence of the first insulating film 831 (see FIG. 4D). Therefore, in the above Manufacturing Method 2, the film formation of the photoelectric conversion layer 15 is easier than in the above Manufacturing Method 1.

[0063] As described above, according to the imaging device 100 according to Embodiment 1 of the present disclosure, a photoelectric conversion layer 15 having a first surface 15A and a second surface 15B located on the opposite side of the first surface 15A, a first electrode 11 located on the first surface 15A side, and a second electrode 16 located on the second surface 15B side are provided. In the thickness direction (for example, the Z-axis direction) of the photoelectric conversion layer 15, a region overlapping the first electrode 11 is defined as a first region R1, and a region deviating from the first electrode 11 is defined as a second region R2. The film thickness T1 of the photoelectric conversion layer 15 in at least a part of the first region R1 is thinner than the film thickness T2 of the photoelectric conversion layer 15 in the second region R2. For example, T1 is zero.

[0064] According to this, even when oblique incident light is incident above the first electrode 11, the imaging device 100 can suppress photoelectric conversion and charge accumulation above the first electrode 11. The thinner the film thickness T1, the more effectively photoelectric conversion and charge accumulation above the first electrode 11 can be suppressed. Since the imaging device 100 can suppress charge accumulation above the first electrode 11, performance degradation such as inhibition of GS driving can be suppressed, and the oblique incident resistance of GS driving can be improved. Further, since the inflow of charge from above the first electrode 11 to the first electrode 11 is small in the imaging device 100, noise can be reduced.

[0065] Further, the film thickness T2 of the photoelectric conversion layer 15 in the second region R2 can be made thick regardless of the film thickness T1. Thereby, even when a material having a small absorption coefficient is used for the photoelectric conversion layer 15, the absorption rate can be increased by increasing the film thickness T2.

[0066] <Embodiment 2> In Embodiment 1, a case where the second electrode 16 is not disposed in at least a part of the first region R1 was shown. However, the embodiment of the present disclosure is not limited to this.

[0067] FIG. 6 is a cross-sectional view schematically showing a configuration example of the photoelectric conversion unit PD1 of the imaging device 100A according to Embodiment 2 of the present disclosure and its peripheral portion. As shown in FIG. 6, in the imaging device 100A, the second electrode 16 is provided over the entire first region R1. The second electrode 16 is continuously provided from the first region R1 to the second region R2.

[0068] Even with such a configuration, the imaging device 100A can suppress photoelectric conversion and charge accumulation above the first electrode 11. Since the imaging device 100A can suppress charge accumulation above the first electrode 11, it is possible to suppress performance degradation such as inhibition of GS driving, and it is possible to improve the oblique incidence resistance of GS driving.

[0069] <Embodiment 3> In Embodiment 1, a case where the film thickness T1 of the photoelectric conversion layer 15 in at least a part of the first region R1 is zero was described. However, the embodiment of the present disclosure is not limited to this. In the embodiment of the present disclosure, the film thickness T1 may be thinner than the film thickness T2.

[0070] FIG. 7 is a cross-sectional view schematically showing a configuration example of the photoelectric conversion unit PD1 of the imaging device 100B according to Embodiment 3 of the present disclosure and its peripheral portion. As shown in FIG. 7, in the imaging device 100B, a first insulating film 831 is disposed in at least a part of the first region R1. In the Z-axis direction, the first insulating film 831 is disposed between the buffer layer 142 and the photoelectric conversion layer 15.

[0071] In the second region R2, the first insulating film 831 is not disposed. The photoelectric conversion layer 15 is provided on the buffer layer 142 and covers the upper surface 831A and the side surface 831B of the first insulating film 831. As a result, the film thickness T1 of the photoelectric conversion layer 15 in at least a part of the first region R1 is thinner than the film thickness T2 of the photoelectric conversion layer 15 in the second region R2.

[0072] Even with such a configuration, the imaging device 100B can suppress photoelectric conversion and charge accumulation above the first electrode 11. Since the imaging device 100B can suppress charge accumulation above the first electrode 11, it is possible to suppress performance degradation such as inhibition of GS driving, and it is possible to improve the oblique incidence resistance of GS driving.

[0073] <Embodiment 4> FIG. 8 is a cross-sectional view schematically showing a configuration example of the photoelectric conversion unit PD1 of the imaging device 100C according to Embodiment 4 of the present disclosure and its peripheral portion. As shown in FIG. 8, in the imaging device 100C, the photoelectric conversion layer 15 is continuously provided on the buffer layer 142 from the first region R1 to the second region R2. Further, in at least a part of the first region R1, a concave portion 15RE is formed on the first surface 15A of the photoelectric conversion layer 15, and the first insulating film 831 is disposed in the concave portion 15RE. In the Z-axis direction, the first insulating film 831 is disposed between the photoelectric conversion layer 15 and the second electrode 16.

[0074] In the second region R2, the concave portion 15RE is not provided in the photoelectric conversion layer 15. There is no large step between the upper surface 831A of the first insulating film 831 and the first surface 15A of the photoelectric conversion layer 15, and they are flush or substantially flush. The second electrode 16 is continuously provided on the first insulating film 831 and on the photoelectric conversion layer 15. As a result, the film thickness T1 of the photoelectric conversion layer 15 in at least a part of the first region R1 is thinner than the film thickness T2 of the photoelectric conversion layer 15 in the second region R2.

[0075] Even with such a configuration, the imaging device 100C can suppress photoelectric conversion and charge accumulation above the first electrode 11. Since the imaging device 100C can suppress charge accumulation above the first electrode 11, it can suppress performance degradation such as inhibition of GS driving, and can improve the oblique incidence resistance of GS driving.

[0076] <Embodiment 5> In an embodiment of the present disclosure, a gate electrode of a transistor may be arranged on the interlayer insulating film 81 side by side with the first electrode 11 and the third electrode 12.

[0077] FIG. 9 is a cross-sectional view schematically showing a configuration example of a photoelectric conversion unit PD1 of an imaging device 100D according to Embodiment 5 of the present disclosure and its peripheral portion. As shown in FIG. 9, in the imaging device 100D, a gate electrode 13 of a transfer transistor is arranged on the interlayer insulating film 81 side by side with the first electrode 11 and the third electrode 12. For example, in the horizontal direction, the gate electrode 13 of the transfer transistor is arranged between the first electrode 11 and the third electrode 12. Above at least a part of the gate electrode 13 of the transfer transistor, a first insulating film 831 is arranged instead of the photoelectric conversion layer 15.

[0078] Even with such a configuration, the imaging device 100D can suppress photoelectric conversion and charge accumulation above the first electrode 11. Since the imaging device 100D can suppress charge accumulation above the first electrode 11, it can suppress performance degradation such as inhibition of GS driving, and can improve the oblique incidence resistance of GS driving.

[0079] <Embodiment 6> FIG. 10 is a block diagram showing a configuration example of an imaging device 200 according to Embodiment 6 of the present disclosure. The imaging device 200 shown in FIG. 10 includes an imaging region 111 in which stacked imaging elements 101 are arranged in a two-dimensional array, and a vertical drive circuit 112, a column signal processing circuit 113, a horizontal drive circuit 114, an output circuit 115, a drive control circuit 116, etc. as its drive circuit (peripheral circuit).

[0080] The stacked image sensor 101 has, for example, the same structure as any one or more of the imaging devices 100 to 100D described in Embodiments 1 to 5. The vertical drive circuit 112, the column signal processing circuit 113, the horizontal drive circuit 114, the output circuit 115, and the drive control circuit 116 (hereinafter collectively referred to as peripheral circuits) are composed of well-known circuits. Further, the peripheral circuits may be composed of various circuits used in conventional CCD image sensors and CMOS image sensors. In FIG. 10, the display of the reference numeral "101" in the stacked image sensor 101 is shown only in one line.

[0081] Based on the vertical synchronization signal, the horizontal synchronization signal, and the master clock, the drive control circuit 116 generates a clock signal and a control signal that serve as the basis for the operations of the vertical drive circuit 112, the column signal processing circuit 113, and the horizontal drive circuit 114. Then, the generated clock signal and control signal are input to the vertical drive circuit 112, the column signal processing circuit 113, and the horizontal drive circuit 114.

[0082] The vertical drive circuit 112 is composed of, for example, a shift register, and sequentially selects and scans each stacked image sensor 101 in the imaging region 111 in the vertical direction row by row. Then, the pixel signal (image signal) based on the current (signal) generated according to the light reception amount in each stacked image sensor 101 is sent to the column signal processing circuit 113 via the signal line (data output line) 117. One signal line (data output line) 117 includes, for example, one or more of the signal lines (data output lines) VSL1, VSL2, VSL3... shown in FIG. 2.

[0083] The column signal processing circuit 113 is arranged, for example, for each column of the stacked image sensor 101. The column signal processing circuit 113 performs signal processing such as noise removal and signal amplification on the image signal output from the stacked image sensors 101 for one row, using the signal from the black reference pixel (not shown, formed around the effective pixel region) for each imaging device. The output stage of the column signal processing circuit 113 is connected to the horizontal signal line 118 via a horizontal selection switch (not shown).

[0084] The horizontal drive circuit 114 is constituted by, for example, a shift register. The horizontal drive circuit 114 sequentially selects each of the column signal processing circuits 113 by sequentially outputting horizontal scanning pulses to the above-described horizontal selection switches. The selected column signal processing circuit 113 outputs a signal to the horizontal signal line 118.

[0085] The output circuit 115 performs signal processing on the signals sequentially supplied from each of the column signal processing circuits 113 via the horizontal signal line 118 and outputs the processed signals.

[0086] <Other Embodiments> As described above, although the present disclosure has been described by way of embodiments and modifications, it should not be understood that the discussions and drawings forming a part of this disclosure limit the present disclosure. Various alternative embodiments, examples, and operation techniques will become apparent to those skilled in the art from this disclosure. For example, in the above-described Embodiment 1, the second electrode 16 may be continuously provided from the first surface 15A of the photoelectric conversion layer 15 through the side surface of the photoelectric conversion layer 15 to the buffer layer 142 in the first region R1.

[0087] Alternatively, in the above-described Embodiments 1, 2, and 5, a light-shielding layer may be provided above the conductive layer 14 in the first region R1. In the above-described Embodiments 3 to 5, a light-shielding layer may be provided on the photoelectric conversion layer 15 in the first region R1. With such a configuration, photoelectric conversion in the conductive layer 14 and the photoelectric conversion layer 15 in the first region R1 can be further suppressed.

[0088] Thus, it goes without saying that the technology according to the present disclosure (this technology) includes various embodiments and the like not described herein. At least one of various omissions, substitutions, and changes of components can be made without departing from the gist of the above-described embodiments and modifications. Also, the effects described in this specification are merely examples and are not limiting, and there may be other effects.

[0089] <Application Example to Electronic Devices> The technology according to the present disclosure (this technology) can be applied to various electronic devices such as imaging systems such as digital still cameras and digital video cameras (hereinafter collectively referred to as cameras), mobile devices such as mobile phones equipped with an imaging function, or other devices equipped with an imaging function.

[0090] FIG. 11 is a conceptual diagram showing an example in which the technology according to the present disclosure (this technology) is applied to an electronic device 300. As shown in FIG. 11, the electronic device 300 is, for example, a camera, and includes a solid-state imaging device 201, an optical lens 210, a shutter device 211, a drive circuit 212, and a signal processing circuit 213. The optical lens 210 is an example of the "optical component" of the present disclosure.

[0091] The light transmitted through the optical lens 210 is incident on the solid-state imaging device 201. For example, the optical lens 210 forms an image of object light (incident light) on the imaging surface of the solid-state imaging device 201. As a result, signal charges are accumulated in the solid-state imaging device 201 for a certain period. The shutter device 211 controls the light irradiation period and the light shielding period to the solid-state imaging device 201. The drive circuit 212 supplies a drive signal for controlling the transfer operation and the like of the solid-state imaging device 201 and the shutter operation of the shutter device 211. Signal transfer of the solid-state imaging device 201 is performed by the drive signal (timing signal) supplied from the drive circuit 212. The signal processing circuit 213 performs various signal processes. For example, the signal processing circuit 213 processes the signal output from the solid-state imaging device 201. The video signal subjected to signal processing is stored in a storage medium such as a memory or output to a monitor.

[0092] In the electronic device 300, any one or more of the above-described imaging devices 100 to 100D and 200 are applied to the solid-state imaging device 201. Thereby, an electronic device 300 with improved performance can be obtained. Note that the electronic device 300 is not limited to a camera. The electronic device 300 may be a mobile device such as a mobile phone equipped with an imaging function, or other device equipped with an imaging function.

[0093] <Application Example to Endoscopic Surgery System> The technology according to the present disclosure (this technology) can be applied to various products. For example, the technology according to the present disclosure may be applied to an endoscopic surgery system.

[0094] FIG. 12 is a diagram showing an example of a schematic configuration of an endoscopic surgery system to which the technology according to the present disclosure (this technology) can be applied.

[0095] In FIG. 12, a state where an operator (doctor) 11131 is performing surgery on a patient 11132 on a patient bed 11133 using an endoscopic surgery system 11000 is illustrated. As shown in the figure, the endoscopic surgery system 11000 includes an endoscope 11100, other surgical instruments 11110 such as a pneumoperitoneum tube 11111 and an energy treatment instrument 11112, a support arm device 11120 that supports the endoscope 11100, and a cart 11200 on which various devices for endoscopic surgery are mounted.

[0096] The endoscope 11100 includes a lens barrel 11101 whose tip region of a predetermined length is inserted into the body cavity of the patient 11132, and a camera head 11102 connected to the base end of the lens barrel 11101. In the illustrated example, an endoscope 11100 configured as a so-called rigid endoscope having a rigid lens barrel 11101 is shown, but the endoscope 11100 may be configured as a so-called flexible endoscope having a flexible lens barrel.

[0097] An opening into which an objective lens is fitted is provided at the tip of the lens barrel 11101. A light source device 11203 is connected to the endoscope 11100, and the light generated by the light source device 11203 is guided to the tip of the lens barrel through a light guide extending inside the lens barrel 11101 and irradiated toward an observation target in the body cavity of the patient 11132 through the objective lens. Note that the endoscope 11100 may be a direct vision endoscope, a forward oblique endoscope, or a side vision endoscope.

[0098] Inside the camera head 11102, an optical system and an imaging element are provided, and the reflected light (observation light) from the observation target is condensed onto 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 the observation image, is generated. The image signal is transmitted as RAW data to a camera control unit (CCU) 11201.

[0099] The CCU 11201 is composed of a CPU (Central Processing Unit), a GPU (Graphics Processing Unit), etc., and comprehensively controls the operations of the endoscope 11100 and the display device 11202. Further, the CCU 11201 receives the image signal from the camera head 11102, and performs various image processes for displaying an image based on the image signal, such as development processing (demosaicing processing), on the image signal.

[0100] The display device 11202 displays an image based on the image signal on which image processing has been performed by the CCU 11201 under the control of the CCU 11201.

[0101] The light source device 11203 is composed of a light source such as an LED (Light Emitting Diode), and supplies irradiation light for photographing the surgical site, etc. to the endoscope 11100.

[0102] The input device 11204 is an input interface for the endoscope surgical system 11000. The user can input various information and instruction inputs to the endoscope surgical system 11000 via the input device 11204. For example, the user inputs an instruction to change imaging conditions (type of irradiation light, magnification, focal length, etc.) by the endoscope 11100.

[0103] The treatment device control device 11205 controls the drive of the energy treatment device 11112 for tissue cauterization, incision, or blood vessel sealing. The pneumoperitoneum device 11206 injects gas into the body cavity of the patient 11132 via the pneumoperitoneum tube 11111 in order to expand the body cavity of the patient for the purpose of securing the visual field by the endoscope 11100 and securing the working space for the surgeon. The recorder 11207 is a device capable of recording various information related to the surgery. The printer 11208 is a device capable of printing various information related to the surgery in various formats such as text, images, or graphs.

[0104] Note that the light source device 11203 that supplies the irradiation light when photographing the surgical site with the endoscope 11100 can be configured from a white light source composed of, for example, an LED, a laser light source, or a combination thereof. When the white light source is configured by a combination of RGB laser light sources, since the output intensity and output timing of each color (each wavelength) can be controlled with high precision, the white balance of the captured image can be adjusted in the light source device 11203. Further, in this case, the laser light from each of the RGB laser light sources is irradiated to the observation target in a time-division manner, and by controlling the drive of the imaging element of the camera head 11102 in synchronization with the irradiation timing, it is also possible to capture images corresponding to each of RGB in a time-division manner. According to this method, a color image can be obtained without providing a color filter on the imaging element.

[0105] Further, the drive of the light source device 11203 may be controlled so as to change the intensity of the output light at predetermined time intervals. By controlling the drive of the imaging element of the camera head 11102 in synchronization with the timing of the change in the intensity of the light and acquiring images in a time-division manner and synthesizing the images, it is possible to generate a so-called high-dynamic range image without black crush and white clip.

[0106] In addition, the light source device 11203 may be configured to supply light in a predetermined wavelength band corresponding to special light observation. In special light observation, for example, by utilizing the wavelength dependence of light absorption in body tissues, a narrow-band light is irradiated as compared with the irradiation light (i.e., white light) during normal observation, so as to capture a predetermined tissue such as blood vessels in the mucosal surface layer with high contrast, so-called narrow-band imaging is performed. Alternatively, in special light observation, fluorescence observation may be performed to obtain an image by fluorescence generated by irradiating excitation light. In fluorescence observation, excitation light is irradiated onto the body tissue and fluorescence from the body tissue is observed (autofluorescence observation), or a reagent such as indocyanine green (ICG) is locally injected into the body tissue and excitation light corresponding to the fluorescence wavelength of the reagent is irradiated onto the body tissue to obtain a fluorescence image. The light source device 11203 can be configured to supply such narrow-band light and / or excitation light corresponding to special light observation.

[0107] FIG. 13 is a block diagram showing an example of the functional configuration of the camera head 11102 and the CCU 11201 shown in FIG. 12.

[0108] The camera head 11102 includes a lens unit 11401, an imaging unit 11402, a drive unit 11403, a communication unit 11404, and a camera head control unit 11405. The CCU 11201 includes a communication unit 11411, an image processing unit 11412, and a control unit 11413. The camera head 11102 and the CCU 11201 are communicably connected to each other by a transmission cable 11400.

[0109] The lens unit 11401 is an optical system provided at a connection portion with the lens barrel 11101. Observation light taken in from the tip of the lens barrel 11101 is guided to the camera head 11102 and enters the lens unit 11401. The lens unit 11401 is configured by combining a plurality of lenses including a zoom lens and a focus lens.

[0110] The imaging unit 11402 is composed of an image sensor. The image sensor constituting the imaging unit 11402 may be one (so-called single-plate type) or a plurality (so-called multi-plate type). When the imaging unit 11402 is configured as a multi-plate type, for example, image signals corresponding to RGB respectively may be generated by each image sensor, and a color image may be obtained by synthesizing them. Alternatively, the imaging unit 11402 may be configured to have a pair of image sensors for respectively acquiring right-eye and left-eye image signals corresponding to 3D (Dimensional) display. By performing 3D display, the surgeon 11131 can more accurately grasp the depth of the biological tissue in the surgical site. When the imaging unit 11402 is configured as a multi-plate type, a plurality of lens units 11401 may be provided corresponding to each image sensor.

[0111] Also, the imaging unit 11402 does not necessarily have to be provided on the camera head 11102. For example, the imaging unit 11402 may be provided immediately behind the objective lens inside the lens barrel 11101.

[0112] The drive unit 11403 is composed of an actuator and moves the zoom lens and the focus lens of the lens unit 11401 along the optical axis by a predetermined distance under the control from the camera head control unit 11405. Thereby, the magnification and focus of the captured image by the imaging unit 11402 can be appropriately adjusted.

[0113] The communication unit 11404 is composed of a communication device for transmitting and receiving various information to and from the CCU 11201. The communication unit 11404 transmits the image signal obtained from the imaging unit 11402 as RAW data to the CCU 11201 via the transmission cable 11400.

[0114] In addition, the communication unit 11404 receives a control signal for controlling the drive of the camera head 11102 from the CCU 11201 and supplies it to the camera head control unit 11405. The control signal includes information related to imaging conditions, such as information specifying the frame rate of the captured image, information specifying the exposure value at the time of imaging, and / or information specifying the magnification and focus of the captured image.

[0115] Note that the imaging conditions such as the above frame rate, exposure value, magnification, and focus may be appropriately specified by the user, or may be automatically set by the control unit 11413 of the CCU 11201 based on the acquired image signal. In the latter case, so-called AE (Auto Exposure) function, AF (Auto Focus) function, and AWB (Auto White Balance) function are installed in the endoscope 11100.

[0116] The camera head control unit 11405 controls the drive of the camera head 11102 based on the control signal from the CCU 11201 received via the communication unit 11404.

[0117] The communication unit 11411 is composed of a communication device for transmitting and receiving various information to and from the camera head 11102. The communication unit 11411 receives an image signal transmitted from the camera head 11102 via the transmission cable 11400.

[0118] In addition, the communication unit 11411 transmits a control signal for controlling the drive of the camera head 11102 to the camera head 11102. The image signal and the control signal can be transmitted by telecommunication, optical communication, etc.

[0119] The image processing unit 11412 performs various image processes on the image signal, which is RAW data transmitted from the camera head 11102.

[0120] The control unit 11413 performs various controls related to imaging of the surgical site and other areas by the endoscope 11100, and display of the captured images obtained by imaging the surgical site and other areas. For example, the control unit 11413 generates a control signal for controlling the drive of the camera head 11102.

[0121] Also, the control unit 11413 causes the display device 11202 to display a captured image showing the surgical site and other areas based on the image signal that has been subjected to image processing by the image processing unit 11412. At this time, the control unit 11413 may recognize various objects in the captured image using various image recognition techniques. For example, the control unit 11413 can recognize surgical instruments such as forceps, specific biological sites, bleeding, mist during use of the energy treatment device 11112, etc. by detecting the shape, color, etc. of the edges of the objects included in the captured image. When causing the display device 11202 to display the captured image, the control unit 11413 may use the recognition result to superimpose and display various surgical support information on the image of the surgical site. By superimposing and presenting the surgical support information to the surgeon 11131, the burden on the surgeon 11131 can be reduced and the surgeon 11131 can surely proceed with the surgery.

[0122] The transmission cable 11400 connecting the camera head 11102 and the CCU 11201 is an electrical signal cable corresponding to electrical signal communication, an optical fiber corresponding to optical communication, or a composite cable of these.

[0123] Here, in the illustrated example, communication is performed wired using the transmission cable 11400, but communication between the camera head 11102 and the CCU 11201 may be performed wirelessly.

[0124] The above has described an example of an endoscopic surgery system to which the technology according to the present disclosure can be applied. The technology according to the present disclosure can be applied to, among the configurations described above, the endoscope 11100, the imaging unit 11402 of the camera head 11102, the image processing unit 11412 of the CCU 11201, and the like. Specifically, any one or more of the imaging devices 100 to 100D and 200 described above can be applied to the imaging unit 10402. By applying the technology according to the present disclosure to the endoscope 11100, the imaging unit 11402 of the camera head 11102, the image processing unit 11412 of the CCU 11201, and the like, a clearer surgical site image can be obtained, so that the surgeon can surely confirm the surgical site. Further, by applying the technology according to the present disclosure to the endoscope 11100, the imaging unit 11402 of the camera head 11102, the image processing unit 11412 of the CCU 11201, and the like, a surgical site image can be obtained with lower latency, so that it becomes possible to perform a treatment with the same feeling as when the surgeon is observing the surgical site by touching.

[0125] Here, although an endoscopic surgery system has been described as an example, the technology according to the present disclosure may be applied to, for example, a microscope surgery system or the like.

[0126] <Application Example to Mobile Objects> The technology (this technology) according to the present disclosure can be applied to various products. For example, the technology according to the present disclosure may be realized as a device mounted on any type of mobile object such as an automobile, an electric vehicle, a hybrid electric vehicle, a motorcycle, a bicycle, a personal mobility device, an airplane, a drone, a ship, a robot, or the like.

[0127] FIG. 14 is a block diagram showing a schematic configuration example of a vehicle control system which is an example of a mobile object control system to which the technology according to the present disclosure can be applied.

[0128] The vehicle control system 12000 includes a plurality of electronic control units connected via a communication network 12001. In the example shown in FIG. 14, the vehicle control system 12000 includes a drive system control unit 12010, a body system control unit 12020, an outside vehicle information detection unit 12030, an inside vehicle information detection unit 12040, and an integrated control unit 12050. Further, as a functional configuration of the integrated control unit 12050, a microcomputer 12051, an audio-visual output unit 12052, and an in-vehicle network I / F (interface) 12053 are illustrated.

[0129] The drive system control unit 12010 controls the operation of devices related to the drive system of the vehicle according to various programs. For example, the drive system control unit 12010 functions as a control device for a driving force generation device for generating a driving force of the vehicle such as an internal combustion engine or a driving motor, a driving force transmission mechanism for transmitting the driving force to the wheels, a steering mechanism for adjusting the steering angle of the vehicle, and a braking device for generating a braking force of the vehicle.

[0130] The body system control unit 12020 controls the operation of various devices installed in the vehicle body according to various programs. For example, the body system control unit 12020 functions as a control device for a keyless entry system, a smart key system, a power window device, or various lamps such as a headlamp, a backlamp, a brake lamp, a turn signal, or a fog lamp. In this case, radio waves transmitted from a portable device that replaces the key or signals of various switches can be input to the body system control unit 12020. The body system control unit 12020 receives these inputs of radio waves or signals and controls the door lock device, the power window device, the lamps, etc. of the vehicle.

[0131] The vehicle external information detection unit 12030 detects information outside the vehicle equipped with the vehicle control system 12000. For example, an imaging unit 12031 is connected to the vehicle external information detection unit 12030. The vehicle external information detection unit 12030 causes the imaging unit 12031 to capture an image outside the vehicle and receives the captured image. The vehicle external information detection unit 12030 may perform object detection processing or distance detection processing on objects such as people, vehicles, obstacles, signs, or characters on the road surface based on the received image.

[0132] The imaging unit 12031 is an optical sensor that receives light and outputs an electrical signal corresponding to the amount of received light. The imaging unit 12031 can output the electrical signal as an image or as ranging information. Also, the light received by the imaging unit 12031 may be visible light or non-visible light such as infrared light.

[0133] The vehicle interior information detection unit 12040 detects information inside the vehicle. For example, a driver state detection unit 12041 that detects the state of the driver is connected to the vehicle interior information detection unit 12040. The driver state detection unit 12041 includes, for example, a camera that images the driver, and the vehicle interior information detection unit 12040 may calculate the degree of driver fatigue or concentration based on the detection information input from the driver state detection unit 12041, or may determine whether the driver is dozing off.

[0134] The microcomputer 12051 can calculate control target values for the driving force generation device, the steering mechanism, or the braking device based on the vehicle interior and exterior information acquired by the vehicle external information detection unit 12030 or the vehicle interior information detection unit 12040, and output a control command to the drive system control unit 12010. For example, the microcomputer 12051 can perform cooperative control for realizing functions of an ADAS (Advanced Driver Assistance System) including collision avoidance or shock mitigation of the vehicle, following driving based on the inter-vehicle distance, vehicle speed maintenance driving, collision warning of the vehicle, or lane departure warning of the vehicle.

[0135] Further, the microcomputer 12051 can perform cooperative control for the purpose of autonomous driving or the like that autonomously travels without relying on the driver's operation by controlling a driving force generator, a steering mechanism, a braking device, etc. based on information around the vehicle acquired by the vehicle exterior information detection unit 12030 or the vehicle interior information detection unit 12040.

[0136] Also, the microcomputer 12051 can output a control command to the body system control unit 12020 based on the vehicle exterior information acquired by the vehicle exterior information detection unit 12030. For example, the microcomputer 12051 can perform cooperative control for the purpose of anti-glare, such as controlling the headlamp according to the position of a preceding vehicle or an oncoming vehicle detected by the vehicle exterior information detection unit 12030 and switching the high beam to the low beam.

[0137] The audio-visual output unit 12052 transmits at least one of an audio output signal and a video output signal to an output device capable of notifying information visually or auditorily to the vehicle occupants or to the outside of the vehicle. In the example of FIG. 14, the audio speaker 12061, the display unit 12062, and the instrument panel 12063 are illustrated as the output devices. The display unit 12062 may include, for example, at least one of an on-board display and a head-up display.

[0138] FIG. 15 is a diagram showing an example of the installation position of the imaging unit 12031.

[0139] In FIG. 15, the vehicle 12100 has imaging units 12101, 12102, 12103, 12104, and 12105 as the imaging unit 12031.

[0140] The imaging units 12101, 12102, 12103, 12104, and 12105 are provided at positions such as the front nose, side mirrors, rear bumper, back door, and the upper part of the windshield inside the vehicle cabin of the vehicle 12100, for example. The imaging unit 12101 provided at the front nose and the imaging unit 12105 provided at the upper part of the windshield inside the vehicle cabin mainly acquire images in front of the vehicle 12100. The imaging units 12102 and 12103 provided at the side mirrors mainly acquire images on the sides of the vehicle 12100. The imaging unit 12104 provided at the rear bumper or the back door mainly acquires images behind the vehicle 12100. The front images acquired by the imaging units 12101 and 12105 are mainly used for detecting a preceding vehicle or detecting pedestrians, obstacles, traffic lights, traffic signs, or lanes, etc.

[0141] Note that FIG. 15 shows an example of the imaging ranges of the imaging units 12101 to 12104. The imaging range 12111 indicates the imaging range of the imaging unit 12101 provided at the front nose, the imaging ranges 12112 and 12113 indicate the imaging ranges of the imaging units 12102 and 12103 provided at the side mirrors respectively, and the imaging range 12114 indicates the imaging range of the imaging unit 12104 provided at the rear bumper or the back door. For example, by overlapping the image data captured by the imaging units 12101 to 12104, an overhead image of the vehicle 12100 as seen from above can be obtained.

[0142] At least one of the imaging units 12101 to 12104 may have a function of acquiring distance information. For example, at least one of the imaging units 12101 to 12104 may be a stereo camera composed of a plurality of imaging elements, or may be an imaging element having pixels for phase difference detection.

[0143] For example, based on the distance information obtained from the imaging units 12101 to 12104, the microcomputer 12051 determines the distance to each solid object within the imaging ranges 12111 to 12114 and the temporal change of this distance (relative speed with respect to the vehicle 12100). In particular, for the closest solid object on the traveling path of the vehicle 12100, a solid object traveling in substantially the same direction as the vehicle 12100 at a predetermined speed (e.g., 0 km / h or more) can be extracted as the preceding vehicle. Further, the microcomputer 12051 can set the inter-vehicle distance that should be secured in advance in front of the preceding vehicle and perform automatic braking control (including follow-up stop control), automatic acceleration control (including follow-up start control), and the like. Thus, cooperative control for the purpose of automatic driving that autonomously travels without relying on the driver's operation can be performed.

[0144] For example, based on the distance information obtained from the imaging units 12101 to 12104, the microcomputer 12051 classifies and extracts solid object data regarding solid objects into two-wheeled vehicles, ordinary vehicles, large vehicles, pedestrians, utility poles, and other solid objects, and can use it for automatic avoidance of obstacles. For example, the microcomputer 12051 discriminates obstacles around the vehicle 12100 into obstacles visible to the driver of the vehicle 12100 and obstacles difficult to visually recognize. Then, the microcomputer 12051 determines a collision risk indicating the degree of risk of collision with each obstacle. When the collision risk is equal to or higher than a set value and there is a possibility of collision, the microcomputer 12051 can output an alarm to the driver via the audio speaker 12061 or the display unit 12062, or perform forced deceleration or avoidance steering via the drive system control unit 12010 to provide driving assistance for collision avoidance.

[0145] At least one of the imaging units 12101 to 12104 may be an infrared camera that detects infrared rays. For example, the microcomputer 12051 can recognize a pedestrian by determining whether a pedestrian exists in the captured images of the imaging units 12101 to 12104. Such recognition of a pedestrian is performed, for example, by a procedure of extracting feature points in the captured images of the imaging units 12101 to 12104 as infrared cameras and a procedure of performing pattern matching processing on a series of feature points indicating the outline of an object to determine whether it is a pedestrian. When the microcomputer 12051 determines that a pedestrian exists in the captured images of the imaging units 12101 to 12104 and recognizes the pedestrian, the audio-visual output unit 12052 controls the display unit 12062 to superimpose and display a rectangular outline for emphasizing the recognized pedestrian. Further, the audio-visual output unit 12052 may control the display unit 12062 to display an icon or the like indicating a pedestrian at a desired position.

[0146] As described above, an example of a vehicle control system to which the technology according to the present disclosure can be applied has been described. The technology according to the present disclosure can be applied to the imaging unit 12031 and the like among the configurations described above. Specifically, any one or more of the imaging devices 100 to 1XXD and 200 described above can be applied to the imaging unit 12031. By applying the technology according to the present disclosure to the imaging unit 12031, a more visible captured image can be obtained, so that it is possible to reduce the driver's fatigue.

[0147] Note that the present disclosure can also adopt the following configuration. (1) A photoelectric conversion layer having a first surface and a second surface located on the opposite side of the first surface, A first electrode located on the first surface side, A second electrode located on the second surface side, and comprising, In the thickness direction of the photoelectric conversion layer, when a region overlapping the first electrode is defined as a first region and a region deviating from the first electrode is defined as a second region, An imaging device in which a first film thickness of the photoelectric conversion layer in at least a part of the first region is thinner than a second film thickness of the photoelectric conversion layer in the second region. (2) The first film thickness is zero. The imaging device according to (1) above. (3) Further comprising a conductive layer in contact with the photoelectric conversion layer and the first electrode. The imaging device according to (1) or (2) above. (4) The conductive layer A semiconductor layer in contact with the first electrode, A buffer layer laminated on the semiconductor layer and in contact with the photoelectric conversion layer. The imaging device according to (3) above. (5) Further comprising a first insulating layer disposed in the first region and in contact with the photoelectric conversion layer. The imaging device according to (3) or (4) above. (6) The first insulating layer is disposed between the conductive layer and the photoelectric conversion layer. The imaging device according to (5) above. (7) The first insulating layer is disposed in front of the photoelectric conversion layer and the second electrode. The imaging device according to (5) above. (8) A third electrode disposed on the opposite side of the photoelectric conversion layer across the conductive layer, And a second insulating layer disposed between the third electrode and the conductive layer. The third electrode overlaps with the photoelectric conversion layer in the thickness direction. The imaging device according to any one of (3) to (7) above. (9) An optical component, An imaging device into which light transmitted through the optical component is incident, And a signal processing circuit that processes a signal output from the imaging device. The imaging device Has a photoelectric conversion layer having a first surface and a second surface located on the opposite side of the first surface, A first electrode located on the first surface side, And a second electrode located on the second surface side. In the thickness direction of the photoelectric conversion layer, when the region overlapping the first electrode is defined as the first region and the region deviated from the first electrode is defined as the second region, An electronic device in which a first film thickness of the photoelectric conversion layer in at least a part of the first region is thinner than a second film thickness of the photoelectric conversion layer in the second region.

Explanation of symbols

[0148] 11 First electrode 12 Third electrode 13 Gate electrode 14 Conductive layer 15 Photoelectric conversion layer 15A First surface 15B Second surface 15H Through hole 15RE Recessed portion 16 Second electrode 17 Wiring 41 n-type semiconductor region 42, 44, 73 p + layer 43 n-type semiconductor region 45, 46, 51, 52, 53 Gate portion 45C, 46C Region 46A Transfer channel 51A, 52A, 53A Channel formation region 51B, 52B, 53B Drain region 51C, 52C, 53C Source region 61 Contact hole portion 62 Wiring layer 63, 64 Pad portion 65, 66 Connection hole 70 Semiconductor substrate 70A Surface 70B Back surface 71 Element isolation region 72 Oxide film 74 HfO2 film 75 Insulating film 76, 81 Interlayer insulating film 81 Interlayer insulating film 82, 83 Insulating layer 82H, 83H Through hole 90 On-chip micro lens 100, 100A, 100B, 100C, 100D, 200 Imaging device 101 Stacked image sensor 111 Imaging area 112 Vertical drive circuit 113 Column signal processing circuit 114 Horizontal drive circuit 115 Output circuit 116 Drive control circuit 117 Signal line (data output line) 118 Horizontal signal line 141 Semiconductor layer 142 Buffer layer 201 Solid-state imaging device 210 Optical lens 211 Shutter device 212 Drive circuit 213 Signal processing circuit 300 Electronic equipment 831 First insulating film 831A Upper surface 831B Side surface 832 Second insulating film 10402 Imaging unit 11000 Endoscopic surgery system 11100 Endoscope 11101 Lens barrel 11102 Camera head 11110 Surgical instrument 11111 Pneumoperitoneum tube 11112 Energy treatment instrument 11120 Support arm device 11131 Operator (doctor) 11132 Patient 11133 Patient bed 11200 Cart 11201 Camera control unit (CCU) 11202 Display device 11203 Light source device 11204 Input device 11205 Treatment instrument control device 11206 Pneumoperitoneum device 11207 Recorder 11208 Printer 11400 Transmission Cable 11401 Lens Unit 11402 Imaging Unit 11403 Driving Unit 11404 Communication Unit 11405 Camera Head Control Unit 11411 Communication Unit 11412 Image Processing Unit 11413 Control Unit 12000 Vehicle Control System 12001 Communication Network 12010 Drive System Control Unit 12020 Body System Control Unit 12030 Vehicle External Information Detection Unit 12031 Imaging Unit 12040 Vehicle Internal Information Detection Unit 12041 Driver State Detection Unit 12050 Integrated Control Unit 12051 Microcomputer 12052 Audio and Image Output Unit 12061 Audio Speaker 12062 Display Unit 12063 Instrument Panel 12100 Vehicle 12101, 12102, 12103, 12104, 12105 Imaging Unit 12111, 12112, 12113, 12114 Imaging Range FD1 First Floating Diffusion Layer FD2 Second Floating Diffusion Layer FD3 Third Floating Diffusion Layer PD1, PD2, PD3 Photoelectric Conversion Unit R1 First Region R2 Second Region T1, T2 Film Thickness TG2, TG3 Transfer Gate Line TR1amp, TR2amp, TR3amp Amplification Transistor TR1rst, TR2rst, TR3rst Reset Transistor TR1sel, TR2sel, TR3sel selection transistors TR2trs, TR3trs transfer transistors VDD power supply VOA wiring VSL1, VSL2, VSL3 signal lines (data output lines)

Claims

1. A photoelectric conversion layer having a first surface and a second surface located on the opposite side of the first surface, a first electrode located on the first surface side, a second electrode located on the second surface side, and comprising: In the thickness direction of the photoelectric conversion layer, when a region overlapping with the first electrode is defined as a first region and a region deviating from the first electrode is defined as a second region, a first film thickness of the photoelectric conversion layer in a part of the first region is zero, An imaging device in which the width of the region of the first film thickness is shorter than the width of the first electrode.

2. A semiconductor substrate located on the first surface side of the photoelectric conversion layer, a floating diffusion provided on the semiconductor substrate, further comprising a contact hole penetrating between the front and back surfaces of the semiconductor substrate, In the thickness direction of the photoelectric conversion layer, the contact hole is provided at a position overlapping with the first electrode and the region of the first film thickness, The imaging device according to claim 1, wherein the first electrode is connected to the floating diffusion through the contact hole.

3. The imaging device according to claim 1, further comprising a conductive layer in contact with the photoelectric conversion layer and the first electrode.

4. The conductive layer is a semiconductor layer in contact with the first electrode, The imaging device according to claim 3, having a buffer layer laminated on the semiconductor layer and in contact with the photoelectric conversion layer.

5. The imaging device according to claim 3, further comprising a first insulating layer disposed in the first region and in contact with the photoelectric conversion layer.

6. a third electrode disposed on the opposite side of the photoelectric conversion layer with the conductive layer interposed therebetween, a second insulating layer disposed between the third electrode and the conductive layer, and further comprising: The imaging device according to claim 3, wherein the third electrode overlaps with the photoelectric conversion layer in the thickness direction.

7. An optical component, an imaging device into which light transmitted through the optical component is incident, a signal processing circuit that processes a signal output from the imaging device, and comprising: The imaging device is a photoelectric conversion layer having a first surface and a second surface located on the opposite side of the first surface, a first electrode located on the first surface side, a second electrode located on the second surface side, and comprising: In the thickness direction of the photoelectric conversion layer, when a region overlapping with the first electrode is defined as a first region and a region deviating from the first electrode is defined as a second region, a first film thickness of the photoelectric conversion layer in a part of the first region is zero, An electronic device in which the width of the region of the first film thickness is shorter than the width of the first electrode.

Images