Imaging element and imaging device

Abstract

A camera element according to an embodiment of the present disclosure includes: a semiconductor substrate having an effective pixel region in which a plurality of pixels are arranged and a peripheral region arranged around the effective pixel region; a first electrode including a plurality of electrodes and provided on a light-receiving surface side of the semiconductor substrate; a second electrode provided so as to face the first electrode; a photoelectric conversion section having a charge accumulation layer and a photoelectric conversion layer, the charge accumulation layer and the photoelectric conversion layer being stacked in this order between the first electrode and the second electrode and extending in the effective pixel region; a first hydrogen barrier layer covering a top and side surfaces of the photoelectric conversion layer and a side surface of the charge accumulation layer; an interlayer insulating layer provided between the semiconductor substrate and the photoelectric conversion section; and a separation groove separating the interlayer insulating layer in at least a portion of a region between the effective pixel region and the peripheral region, a side surface and a bottom surface of the separation groove being covered by the first hydrogen barrier layer.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to an imaging element and an imaging device each including a photoelectric conversion layer including an organic semiconductor material. BACKGROUND

[0002] In recent years, a so-called stacked imaging element is used in an imaging device such as a CCD (Charge Coupled Device) image sensor or a CMOS (Complementary Metal Oxide Semiconductor) image sensor. In the stacked imaging element, an organic photoelectric conversion layer including an organic semiconductor material is stacked on a semiconductor substrate including a photodiode embedded and formed therein. In the stacked imaging element, R / G / B signals can be extracted from one pixel without demosaicing processing. Therefore, it has an advantage that false colors are not generated.

[0003] However, the stacked imaging element has the following problem. For example, an inorganic photoelectric conversion section including a photodiode temporarily accumulates charges generated by photoelectric conversion, and then the inorganic photoelectric conversion section transfers the charges to a floating diffusion layer (floating diffusion section; FD). This can completely deplete the inorganic photoelectric conversion section. In contrast, an organic photoelectric conversion section including the organic photoelectric conversion layer directly accumulates charges generated by photoelectric conversion in the floating diffusion layer FD. Therefore, it is difficult to completely deplete the organic photoelectric conversion section. This increases kTC noise, increases random noise, and reduces the quality of a captured image.

[0004] To solve this problem, for example, Patent Literature 1 discloses an imaging element including a charge accumulation electrode in a photoelectric conversion section. The photoelectric conversion section is provided above a semiconductor substrate. In the photoelectric conversion section, a first electrode, a photoelectric conversion layer, and a second electrode are stacked. The charge accumulation electrode is provided separately from the first electrode and is disposed to face the photoelectric conversion layer with an insulating layer interposed therebetween. The imaging element can accumulate charges generated by photoelectric conversion on the charge accumulation electrode. This can completely deplete the charge accumulation section at the start of exposure and erase the charges. As a result, occurrence of phenomena such as an increase in kTC noise and an increase in random noise is suppressed. The reduction in the quality of a captured image is suppressed. In addition, Patent Literature 1 discloses an example in which the photoelectric conversion layer has a structure in which a lower semiconductor layer and an upper photoelectric conversion layer are stacked, and functions as a configuration for preventing recombination of charges accumulated in the photoelectric conversion layer and increasing the transfer efficiency to the first electrode.

[0005] LIST OF CITATIONS

[0006] PATENT LITERATURE

[0007] Patent Literature 1: Japanese Unexamined Patent Application Publication No. 2017-157816 SUMMARY

[0008] Incidentally, the lower semiconductor layer described above is formed, for example, by using an oxide semiconductor material such as IGZO, but the oxide semiconductor material is easily reduced by hydrogen to generate oxygen defects. Thus, the imaging device provided with the lower semiconductor layer can have reduced operation stability, and improvement in reliability is required.

[0009] It is desirable to provide an imaging device and an imaging device, each of which can improve reliability.

[0010] An imaging device according to an embodiment of the present disclosure includes a semiconductor substrate having an effective pixel region in which a plurality of pixels are arranged and a peripheral region arranged around the effective pixel region; a photoelectric conversion section; a first hydrogen barrier layer; an interlayer insulating layer; and a separation groove. The photoelectric conversion section includes a first electrode, a second electrode, and a charge accumulation layer and a photoelectric conversion layer. The first electrode is provided on a light-receiving surface side of the semiconductor substrate and includes a plurality of electrodes. The second electrode is provided so as to oppose the first electrode. The charge accumulation layer and the photoelectric conversion layer are sequentially stacked and provided between the first electrode and the second electrode and extend in the effective pixel region. The first hydrogen barrier layer covers a top and side surfaces of the photoelectric conversion layer and a side surface of the charge accumulation layer. The interlayer insulating layer is provided between the semiconductor substrate and the photoelectric conversion section. The separation groove separates the interlayer insulating layer in at least a portion of a region between the effective pixel region and the peripheral region. A side surface and a bottom surface of the separation groove are covered with the first hydrogen barrier layer.

[0011] An imaging device according to an embodiment of the present disclosure includes the above-described imaging device according to an embodiment of the present disclosure.

[0012] An imaging device and an imaging device according to an embodiment of the present disclosure, each of which is provided with a separation groove that separates an interlayer insulating layer between an effective pixel region and a peripheral region. The interlayer insulating layer is provided between a semiconductor substrate and a photoelectric conversion section. The first hydrogen barrier layer extends over a side surface and a bottom surface of the separation groove. The first hydrogen barrier layer covers a top of a charge accumulation layer and a photoelectric conversion layer that constitute the photoelectric conversion section and side surfaces of the photoelectric conversion layer and the charge accumulation layer. This suppresses entry of hydrogen into the photoelectric conversion layer and the charge accumulation layer via the interlayer insulating layer. BRIEF DESCRIPTION OF DRAWINGS

[0013] Figure 1 is a cross-sectional schematic view that shows a schematic configuration of an imaging device according to a first embodiment of the present disclosure.

[0014] Figure 2 is a cross-sectional schematic view that shows a schematic configuration of an imaging device according to a first embodiment of the present disclosure.Figure 1 A schematic diagram of another example of a planar configuration of the imaging element shown in FIG. 1.

[0015] Figure 3 is a plan view showing Figure 1 A schematic diagram of another example of a planar configuration of the imaging element shown in FIG. 1.

[0016] Figure 4 is a plan view showing Figure 1 A schematic diagram of another example of a planar configuration of the imaging element shown in FIG. 1.

[0017] Figure 5 is a plan view showing Figure 1 A schematic diagram of another example of a planar configuration of the imaging element shown in FIG. 1.

[0018] Figure 6 is Figure 1 An equivalent circuit diagram of the imaging element shown in FIG. 1.

[0019] Figure 7 is a plan view showing Figure 1 A schematic diagram of the arrangement of the lower electrode of the imaging element shown in FIG. 1 and the transistors constituting the controller.

[0020] Figure 8A is a plan view showing Figure 1 A plan schematic diagram of an example of the layout of the lower electrode of the organic photoelectric conversion section shown in FIG. 1.

[0021] Figure 8B is Figure 8A A perspective view of the layout of the lower electrode shown in FIG. 1.

[0022] Figure 9A is a plan view showing Figure 1 A plan schematic diagram of another example of the layout of the lower electrode of the organic photoelectric conversion section shown in FIG. 1.

[0023] Figure 9B is Figure 9A A perspective view of the layout of the lower electrode shown in FIG. 1.

[0024] Figure 10 is a plan view showing Figure 1 A plan schematic diagram of an example of the layout of one inorganic photoelectric conversion section and various transistors associated therewith shown in FIG. 1.

[0025] Figure 11 is a plan view showing Figure 1 A plan schematic diagram of an example of the layout of another inorganic photoelectric conversion section and various transistors associated therewith shown in FIG. 1.

[0026] Figure 12 is a layout diagram of the signal line for driving Figure 1 The accumulation electrode shown in FIG. 1.

[0027] Figure 13 This is a diagram showing a portion of the wiring connected to adjacent photoelectric conversion units and the various transistors associated with them.

[0028] Figure 14 This is a diagram showing a portion of the wiring connected to adjacent photoelectric conversion units and the various transistors associated with them.

[0029] Figure 15 This is a diagram showing a portion of the wiring connected to adjacent photoelectric conversion units and the various transistors associated with them.

[0030] Figure 16A It is used for explanation Figure 1 A cross-sectional view of the manufacturing method of the camera element shown.

[0031] Figure 16B It shows Figure 16A A cross-sectional diagram of the subsequent steps.

[0032] Figure 16C It shows Figure 16B A cross-sectional diagram of the subsequent steps.

[0033] Figure 16D It shows Figure 16C A cross-sectional diagram of the subsequent steps.

[0034] Figure 17 It is shown Figure 1 The timing diagram shows an example of the operation of the camera element.

[0035] Figure 18 This is a schematic cross-sectional view showing the exemplary construction of the imaging element according to a variation of the present disclosure, Example 1.

[0036] Figure 19 It is shown Figure 18 A schematic diagram illustrating an example of a planar structure of a camera element.

[0037] Figure 20 This is a schematic cross-sectional view showing the exemplary construction of the imaging element according to Modification 2 of this disclosure.

[0038] Figure 21 It is shown Figure 20 A schematic diagram illustrating an example of a planar structure of a camera element.

[0039] Figure 22 It is shown Figure 20 A schematic diagram of another example of the planar construction of the imaging element shown.

[0040] Figure 23 This is a schematic cross-sectional view showing the exemplary construction of the imaging element according to Modification 3 of this disclosure.

[0041] Figure 24 is a schematic diagram showing an example of a planar configuration of the imaging element. Figure 23

[0042] Figure 25 is a cross-sectional schematic diagram showing an example of a schematic configuration of the imaging element according to Modification Example 4 of the present disclosure.

[0043] Figure 26 is a cross-sectional schematic diagram showing another example of a schematic configuration of the imaging element according to Modification Example 4 of the present disclosure.

[0044] Figure 27 is a cross-sectional schematic diagram showing a schematic configuration of the imaging element according to Modification Example 5 of the present disclosure.

[0045] Figure 28 is a cross-sectional schematic diagram showing a schematic configuration of the imaging element according to Modification Example 6 of the present disclosure.

[0046] Figure 29 is a cross-sectional schematic diagram showing an example of a schematic configuration of the imaging element according to the second embodiment of the present disclosure.

[0047] Figure 30 is a cross-sectional schematic diagram showing another example of a schematic configuration of the imaging element according to the second embodiment of the present disclosure.

[0048] Figure 31 is a planar schematic diagram showing another example of a layout of the lower electrode constituting the organic photoelectric conversion section according to Modification Example 7 of the present disclosure.

[0049] Figure 32 is a planar schematic diagram showing another example of a layout of one inorganic photoelectric conversion section and various transistors related thereto according to Modification Example 7 of the present disclosure.

[0050] Figure 33 is a planar schematic diagram showing another example of a layout of another inorganic photoelectric conversion section and various transistors related thereto according to Modification Example 7 of the present disclosure.

[0051] Figure 34 is a diagram showing another example of a wiring connected to the photoelectric conversion section and various transistors related thereto according to Modification Example 7 of the present disclosure.

[0052] Figure 35 is a diagram showing another example of a wiring connected to the photoelectric conversion section and various transistors related thereto according to Modification Example 7 of the present disclosure.

[0053] Figure 36 ​is a view showing another example of the wiring connected to the photoelectric conversion section and various transistors related thereto according to Embodiment 7 of the present disclosure.

[0054] Figure 37 is a view showing another example of the wiring connected to the photoelectric conversion section and various transistors related thereto according to Embodiment 7 of the present disclosure.

[0055] Figure 38 is a block diagram showing a configuration of an imaging device including Figure 1 the imaging device shown in FIG. 1.

[0056] Figure 39 is a block diagram showing a configuration of an imaging device including Figure 38 the electronic device (camera) shown in FIG. 1.

[0057] Figure 40 is a block diagram showing an example of a schematic configuration of an in-vivo information acquisition system.

[0058] Figure 41 is a view showing an example of a schematic configuration of an endoscopic surgery system.

[0059] Figure 42 is a block diagram showing an example of a functional configuration of a camera head and a camera control unit (CCU: camera control unit).

[0060] Figure 43 is a block diagram showing an example of a schematic configuration of a vehicle control system.

[0061] Figure 44 is a view for assisting in explaining the mounting positions of the outside-vehicle information detecting section and the imaging section. DETAILED DESCRIPTION

[0062] Hereinafter, embodiments of the present disclosure will be explained in detail with reference to the attached drawings. The following explanation is a specific example of the present disclosure, but the present disclosure is not limited to the following modes. In addition, the present disclosure is not limited to the arrangement, size, and size ratio of each component shown in the drawings, and the like. Note that the explanation is given in the following order.

[0063] 1. First Embodiment (Example of Imaging Element Having Separation Groove Separating Interlayer Insulating Layer Between Effective Pixel Area and Peripheral Area)

[0064] 1-1. Configuration of Imaging Element

[0065] 1-2. Manufacturing Method of Imaging Element

[0066] 1-3. Operation and Effects

[0067] 2. Modification 1 (Example in which double separation grooves are provided around the effective pixel region)

[0068] 3. Modification 2 (Example in which a separation groove is provided around the pad electrode)

[0069] 4. Modification 3 (Example in which separation grooves are respectively provided around the effective pixel region and around the pad electrode)

[0070] 5. Modification 4 (Example of depth of separation groove)

[0071] 6. Modification 5 (Example in which a second hydrogen barrier layer is provided in the lower layer of the photoelectric conversion section 20)

[0072] 7. Modification 6 (Example in which the insulating layer on the lower electrode is formed as a second hydrogen barrier layer)

[0073] 8. Second Embodiment (Example of imaging element further including a guard ring between the effective pixel region and the peripheral region)

[0074] 9. Modification 7 (Another example of pixel layout)

[0075] 10. Application Example

[0076] 11. Application Example

[0077] <1. First Embodiment>

[0078] Figure 1 A cross-sectional configuration of an imaging element (imaging element 10A) according to a first embodiment of the present disclosure is schematically shown. Figure 2 A planar configuration of the imaging element 10A shown is schematically shown. Figure 1 A planar configuration of the imaging element 10A shown is schematically shown. Figure 3 to 5 A planar configuration of the imaging element 10A shown is schematically shown. Figure 1 A planar configuration of the imaging element 10A shown is schematically shown. Note that, Figure 1 A cross section taken along Figure 2 the I-I line shown is shown. Figure 6 is Figure 1 An equivalent circuit diagram of the imaging element 10A shown is shown. Figure 7 An arrangement of the lower electrode 21 of the imaging element 10A shown and the transistors constituting the controller is schematically shown. Figure 1 An arrangement of the lower electrode 21 of the imaging element 10A shown and the transistors constituting the controller is schematically shown. The imaging element 10A is included in, for example, an imaging device (imaging device 1; see Figure 38one pixel (unit pixel P) in the image pickup device 1. The image pickup device 1 has an effective pixel region 110A and a peripheral region 110B. A plurality of pixels are arranged in the effective pixel region 110A. The peripheral region 110B is provided around the effective pixel region 110A. For example, a peripheral circuit such as a row scanning section 131 is formed in the peripheral region 110B. The image pickup element 10A is formed in each of the plurality of pixels.

[0079] The photoelectric conversion section 20 is provided on a light-receiving surface (first surface; surface 30S1) of the semiconductor substrate 30. The photoelectric conversion section 20 has a configuration in which a lower electrode 21 (first electrode) including a plurality of electrodes, an insulating layer 22, a charge accumulation layer 23, a photoelectric conversion layer 24, and an upper electrode 25 (second electrode) are sequentially stacked from the semiconductor substrate 30 side. The charge accumulation layer 23 and the photoelectric conversion layer 24 are formed so as to extend, for example, over the entire effective pixel region 110A, as a common layer of the plurality of pixels provided in the effective pixel region 110A. Further, a hydrogen barrier layer 26 (first hydrogen barrier layer) is formed so as to cover the top and side surfaces of the photoelectric conversion layer 24 and the side surfaces of the charge accumulation layer 23. The image pickup element 10A according to the present embodiment is provided with an interlayer insulating layer 29 between the semiconductor substrate 30 and the photoelectric conversion section 20. The interlayer insulating layer 29 has a separation groove 29H that separates the effective pixel region 110A side and the peripheral region 110B side. The side surfaces and the bottom surface of the separation groove 29H are covered with the hydrogen barrier layer 26. This separation groove 29H corresponds to a specific example of the "separation groove" of the present disclosure. Note that the image pickup element 10A has a pixel sharing structure in which four pixels adjacent to each other share one floating diffusion section FD1, one floating diffusion section FD2, and one floating diffusion section FD3 corresponding thereto.

[0080] (1-1. Configuration of Image Pickup Element)

[0081] The image pickup element 10A is a so-called vertical spectral type image pickup element in which one photoelectric conversion section 20 and two inorganic photoelectric conversion sections 32B and 32R are stacked in the vertical direction. The photoelectric conversion section 20 is formed, for example, by using an organic material. As described above, the photoelectric conversion section 20 is provided on the first surface (back surface; surface 30S1) side of the semiconductor substrate 30. The inorganic photoelectric conversion sections 32B and 32R are embedded and formed in the semiconductor substrate 30 and stacked in the thickness direction of the semiconductor substrate 30.

[0082] Although described in detail below, the photoelectric conversion section 20 includes a charge accumulation layer 23 and a photoelectric conversion layer 24 between a lower electrode 21 and an upper electrode 25. The lower electrode 21 and the upper electrode 25 are disposed in opposition to each other. The photoelectric conversion section 20 is provided with an insulating layer 22 between the lower electrode 21 and the charge accumulation layer 23. The lower electrode 21 of the photoelectric conversion section 20 includes a plurality of electrodes (a readout electrode 21A, an accumulation electrode 21B, and a shield electrode 21C). The readout electrode 21A is electrically connected to the charge accumulation layer 23 via an opening 22H formed in the insulating layer 22. The photoelectric conversion layer 24 includes a p-type semiconductor and an n-type semiconductor, and has a bulk heterojunction structure in the layer. The bulk heterojunction structure is a p / n junction surface formed by mixing the p-type semiconductor and the n-type semiconductor.

[0083] The photoelectric conversion section 20, as well as the inorganic photoelectric conversion sections 32B and 32R, selectively detects light in mutually different wavelength ranges, and performs photoelectric conversion. Specifically, for example, the photoelectric conversion section 20 acquires a color signal of green (G). The inorganic photoelectric conversion sections 32B and 32R acquire a color signal of blue (B) and a color signal of red (R), respectively, by using different absorption coefficients. This enables the image pickup element 10A to acquire multiple types of color signals in one pixel without using a color filter.

[0084] Note that, in the present embodiment, a case in which an electron in a pair of an electron and a hole (electron-hole pair) generated by photoelectric conversion is read out as a signal charge is described (a case in which an n-type semiconductor region is used as a photoelectric conversion layer). In addition, in the drawings, "+" (plus) attached to "p" and "n" indicates a high p-type or n-type impurity concentration.

[0085] The second face (front surface; face 30S2) of the semiconductor substrate 30 is provided with, for example, floating diffusion sections (floating diffusion layers) FD1 (region 35 in the semiconductor substrate 30), FD2, and FD3; transfer transistors TR2trs and TR3trs; amplification transistors (modulation elements) TR1amp and TR2amp; reset transistors TR1rst and TR2rst; and a selection transistor TR1sel. Note that, in the drawings, the first face (face 30S1) side of the semiconductor substrate 30 is referred to as a light incident side S1, and the second face (face 30S2) side is referred to as a wiring layer side S2. The multilayer wiring layer 40, the logic substrate 60, and the support substrate 70 are sequentially stacked on the second face (face 30S2) side of the semiconductor substrate 30.

[0086] The multilayer wiring layer 40 has, for example, a configuration in which the wiring layers 41, 42, and 43 are stacked in the insulating layer 44. The logic substrate 60 is provided with a logic circuit (not shown) and a pad electrode 61 (transfer electrode) for external output. A plurality of (six in this example) pad electrodes 61 are provided in a peripheral region 110B on a surface of the logic substrate 60 on the semiconductor substrate 30 side. As shown, the plurality of pad electrodes 61 are arranged on one side in one direction (for example, the Z-axis direction) of the logic substrate 60. The logic substrate 60 has, for example, a rectangular shape. However, this is not limiting. For example, as shown, the plurality of pad electrodes 61 can be arranged on two opposite sides of the logic substrate 60. For example, as shown, the plurality of pad electrodes 61 can be arranged on two intersecting sides. Alternatively, for example, as shown, the plurality of pad electrodes 61 can be arranged on each of the four sides. In addition, although examples in which a plurality of pad electrodes 61 are arranged are shown respectively, one pad electrode 61 can also be arranged. An opening H is provided on the pad electrode 61. The opening H extends through the semiconductor substrate 30 and the multilayer wiring layer 40. The pad electrode 61 is electrically connected to the outside via this opening H. This connection is established, for example, in a method such as wire bonding or bumping. Figure 2 Figure 2 Figure 3 Figure 4 Figure 5 Figure 2 to 5

[0087] In the photoelectric conversion section 20, as described above, the lower electrode 21, the insulating layer 22, the charge accumulation layer 23, the photoelectric conversion layer 24, and the upper electrode 25 are stacked in this order from the first surface (surface 30S1) side of the semiconductor substrate 30. The lower electrode 21 of each of the image pickup elements 10A is formed separately, for example. Each lower electrode 21 includes a readout electrode 21A, an accumulation electrode 21B, and a shield electrode 21C. The readout electrode 21A and the accumulation electrode 21B are separated from each other with the insulating layer 22 interposed therebetween. The shield electrode 21C surrounds four pixels adjacent to each other. As shown, the readout electrode 21A of the lower electrode 21 is shared by two pixels or four pixels adjacent to each other, and is electrically connected to the charge accumulation layer 23 via, for example, an opening 22H provided in the insulating layer 22. Figure 8A Figure 9A Figure 1 In this example, the charge accumulation layer 23, the photoelectric conversion layer 24, and the upper electrode 25 are provided as a continuous layer common to the plurality of image pickup elements 10A, and extend over the entire effective pixel region 110A. A hydrogen barrier layer 26 is also provided on the upper electrode 25. The hydrogen barrier layer 26 is provided in such a manner as to cover the side surfaces of the upper electrode 25, the photoelectric conversion layer 24, the charge accumulation layer 23, and the insulating layer 22 from the upper portion of the upper electrode 25, for example, in the peripheral region 110B.

[0088] ​​​​​​​​From the semiconductor substrate 30 side, a fixed charge layer 27, an insulating layer 28, and an interlayer insulating layer 29 are provided in this order between the first surface (surface 30S1) of the semiconductor substrate 30 and the lower electrode 21, for example. As described above, the interlayer insulating layer 29 is provided with a separation groove 29H in the peripheral region 110B. The separation groove 29H separates the effective pixel region 110A side and the peripheral region 110B side. The above-described hydrogen barrier layer 26 also covers the side surfaces and the bottom surface of the separation groove 29H extending on the interlayer insulating layer 29 and provided on the interlayer insulating layer 29. A first protective layer 51 and an on-chip lens layer 52 are provided in this order on the hydrogen barrier layer 26.

[0089] A through electrode 34A, 34B, and 34C is provided between the first surface (surface 30S1) and the second surface (surface 30S2) of the semiconductor substrate 30. The through electrode 34A is electrically connected to the readout electrode 21A of the photoelectric conversion section 20. The photoelectric conversion section 20 is connected to, for example, the gate electrode Gamp of the amplification transistor TR1amp and one source / drain region of the reset transistor (reset transistor TR1rst) also serving as the floating diffusion section FD1 via the through electrode 34. This enables the imaging device 10A to advantageously transfer the charge (here, electrons) generated by the photoelectric conversion section 20 on the first surface (surface 30S1) side of the semiconductor substrate 30 to the second surface (surface 30S2) side of the semiconductor substrate 30, thereby improving the characteristics. The through electrode 34B is electrically connected to the accumulation electrode 21B of the photoelectric conversion section 20. This enables voltage to be applied to the accumulation electrode 21B independently of the readout electrode 21A. The through electrode 34C is electrically connected to the shield electrode 21C. This suppresses the leakage of charge to adjacent pixels.

[0090] The lower ends of the through electrodes 34A, 34B, and 34C are connected to the wiring layer 41, respectively. In particular, the through electrode 34A is connected to a connection portion 41A in the wiring layer 41. The connection portion 41A and the floating diffusion section FD1 (region 35) are connected via, for example, a lower first contact 45. The upper end of the through electrode 34A is connected to the readout electrode 21A via, for example, a pad portion 35A, a via V2, a pad portion 36A, and a via V1.

[0091] One through electrode 34A is provided for four pixels adjacent to each other. The through electrode 34A has the function of the connection portion of the gate electrode Gamp of the amplification transistor TR1amp and the floating diffusion section FD1 for each pixel as well as the photoelectric conversion section 20. The through electrode 34A serves as a transfer path for the charge (here, electrons) generated by the photoelectric conversion section 20.

[0092] The reset gate electrode Grst of the reset transistor TR1rst is disposed in the vicinity of the floating diffusion section FD1 (one source / drain region of the reset transistor TR1rst). This enables the reset transistor TR1rst to reset the charge accumulated in the floating diffusion section FD1.

[0093] In the imaging element 10A according to the present embodiment, light incident to the photoelectric conversion section 20 from the upper electrode 25 side is absorbed by the photoelectric conversion layer 24. Excitons generated thereby move to the interface between the electron donor and the electron acceptor constituting the photoelectric conversion layer 24, and undergo exciton dissociation. In other words, the excitons are dissociated into electrons and holes. The charges (electrons and holes) generated here are transported to different electrodes by diffusion caused by a concentration difference of the carriers and an internal electric field caused by a difference in work function between the anode (here, the upper electrode 25) and the cathode (here, the lower electrode 21). The transported charges are detected as a photoelectric current. In addition, by applying a potential between the lower electrode 21 and the upper electrode 25, the transport direction of the electrons and holes can be controlled.

[0094] The configuration and materials of each section and the like are described below.

[0095] The photoelectric conversion section 20 is a photoelectric conversion element that absorbs green light corresponding to part or all of a selected wavelength range (for example, 450 nm or more and 650 nm or less) and generates electron-hole pairs.

[0096] As described above, the lower electrode 21 includes the readout electrode 21A, the accumulation electrode 21B, and the shield electrode 21C formed separately. The readout electrode 21A is used to transport the charges (here, electrons) generated in the photoelectric conversion layer 24 to the floating diffusion section FD1. For example, the readout electrode 21A is connected to the floating diffusion section FD1 via the via hole V1, the pad section 36A, the via hole V2, the pad section 35A, the through electrode 34A, the connection section 41A, and the lower first contact 45. The accumulation electrode 21B is used to accumulate the electrons of the charges generated in the photoelectric conversion layer 24 as signal charges in the charge accumulation layer 23. The accumulation electrode 21B is provided in a region opposing the light receiving surfaces of the inorganic photoelectric conversion sections 32B and 32R formed in the semiconductor substrate 30 and covering these light receiving surfaces. It is desirable that the accumulation electrode 21B be larger than the readout electrode 21A. Thus, a large amount of charges can be accumulated. As described above, the shield electrode 21C is used to suppress leakage of charges to adjacent pixels.

[0097] The lower electrode 21 includes a conductive film having light-transmitting property. The lower electrode 21 includes, for example, ITO (indium tin oxide). However, as a material constituting the lower electrode 21, a tin oxide (SnO2)-based material to which a dopant is added or a zinc oxide (ZnO)-based material obtained by adding a dopant to zinc oxide can be used in addition to the ITO. Examples of the zinc oxide-based material include aluminum zinc oxide (AZO) to which aluminum (Al) is added as a dopant, gallium zinc oxide (GZO) to which gallium (Ga) is added, and indium zinc oxide (IZO) to which indium (In) is added. In addition to these, CuI, InSbO4, ZnMgO, CuInO2, MgIN2O4, CdO, ZnSnO3, and the like can be used. Preferably, the thickness of the lower electrode 21 is, for example, 20 nm to 200 nm. More preferably, the thickness of the lower electrode 21 is 30 nm or more and 100 nm or less.

[0098] The insulating layer 22 serves to electrically insulate the accumulation electrode 21B and the charge accumulation layer 23. The insulating layer 22 is provided, for example, on the interlayer insulating layer 29 and the lower electrode 21 and covers the lower electrode 21. In addition, the insulating layer 22 is provided with an opening 22H above the readout electrode 21A of the lower electrode 21, and the readout electrode 21A and the charge accumulation layer 23 are electrically connected via the opening 22H. The insulating layer 22 includes, for example, a single-layer film including one of, for example, silicon oxide (SiO2), silicon nitride (Si3N4), and silicon oxynitride (SiON), or a laminated film including two or more of them. Note that the above chemical formula is an example. It is assumed that the same type of compound that does not conform to the stoichiometry is included in addition to the above chemical formula. The following chemical formula is also applicable. The thickness of the insulating layer 22 is, for example, 20 nm to 500 nm.

[0099] The charge accumulation layer 23 is provided below the photoelectric conversion layer 24. Specifically, the charge accumulation layer 23 is provided between the insulating layer 22 and the photoelectric conversion layer 24. The charge accumulation layer 23 serves to accumulate signal charges (here, electrons) generated by the photoelectric conversion layer 24. Preferably, the charge accumulation layer 23 is formed by using a material having a higher charge mobility than the photoelectric conversion layer 24 and a larger band gap than the band gap of the photoelectric conversion layer 24. For example, preferably, the band gap of the material constituting the charge accumulation layer 23 is 3.0 eV or more. Examples of such a material include oxide semiconductor materials such as IGZO and organic semiconductor materials. Examples of the organic semiconductor material include transition metal disulfide, silicon carbide, diamond, graphene, carbon nanotube, condensed polycyclic hydrocarbon compound, and condensed heterocyclic compound. The thickness of the charge accumulation layer 23 is, for example, 10 nm or more and 300 nm or less. By providing the charge accumulation layer 23 including the above-described material below the photoelectric conversion layer 24, recombination of charges during charge accumulation can be prevented and the transfer efficiency can be improved.

[0100] The photoelectric conversion layer 24 converts light energy into electric energy. The photoelectric conversion layer 24 includes, for example, two or more types of organic semiconductor materials (p-type semiconductor material or n-type semiconductor material) that function as a p-type semiconductor or an n-type semiconductor, respectively. The photoelectric conversion layer 24 includes a junction surface (p / n junction surface) between these p-type semiconductor material and n-type semiconductor material in the layer. The p-type semiconductor functions as an electron donor (donor) in contrast, and the n-type semiconductor functions as an electron acceptor (acceptor) in contrast. The photoelectric conversion layer 24 provides a field in which an exciton generated upon absorption of light is split into an electron and a hole. Specifically, the exciton is split into the electron and the hole at the interface between the electron donor and the electron acceptor (p / n junction surface).

[0101] In addition to the p-type semiconductor material and the n-type semiconductor material, the photoelectric conversion layer 24 can include an organic material or a so-called dye material. The organic material or the dye material photoelectrically converts light in a predetermined wavelength range and transmits light in other wavelength ranges. In the case where the photoelectric conversion layer 24 is formed by using three types of organic materials including the p-type semiconductor material, the n-type semiconductor material, and the dye material, preferably, the p-type semiconductor material and the n-type semiconductor material are materials that have light transmittance in the visible region (for example, 450 nm to 800 nm), respectively. The thickness of the photoelectric conversion layer 24 is, for example, 50 nm to 500 nm.

[0102] The organic material that constitutes the photoelectric conversion layer 24 includes the following materials. Examples of the dye material include rhodamine-based dyes, merocyanine-based dyes, quinacridone derivatives, subphthalocyanine-based dyes, and derivatives thereof. In addition, the organic material other than the dye material includes pentacene, benzothiophenebenzothiophene, fullerene, and derivatives thereof. The photoelectric conversion layer 24 includes a combination of two or more of the above-described organic materials. Depending on the combination, the above-described organic material functions as a p-type semiconductor or an n-type semiconductor.

[0103] Note that, in the present embodiment, the photoelectric conversion section 20 is an element that photoelectrically converts green light, but can be configured as an element that photoelectrically converts blue light or red light. In this case, the dye material that constitutes the photoelectric conversion layer 24 includes the following materials. In the case of photoelectrically converting blue light, for example, the dye material that constitutes the photoelectric conversion layer 24 includes coumalin dyes, 3-8-hydroxyquinoline aluminum (Alq3), merocyanine-based dyes, and derivatives thereof. In the case of photoelectrically converting red light, for example, the dye material that constitutes the photoelectric conversion layer 24 includes phthalocyanine-based dyes, subphthalocyanine-based dyes, and derivatives thereof.

[0104] Further, the photoelectric conversion layer 24 can use the following organic material. In addition to the above-described organic material, for example, any one of naphthalene, anthracene, phenanthrene, naphthacene, pyrene, perylene, and fluoranthene or a derivative thereof is preferably used as the organic material. Alternatively, a polymer such as phenylenevinylene, fluorene, carbazole, indole, pyrene, pyrrole, methylpyridine, thiophene, acetylene, and diacetylene or a derivative thereof can be used. Further, a metal complex dye, a cyanine-based dye, a merocyanine-based dye, a phenylxanthene-based dye, a triphenylmethane-based dye, a rhodacyanine-based dye, a xanthene-based dye, a macrocyclic azaannulene-based dye, a azulene-based dye, a naphthoquinone, an anthraquinone-based dye, a chain compound in which a condensed polycyclic aromatic group such as anthracene and pyrene and an aromatic ring or a heterocyclic compound are condensed, a cyanine-based dye bonded by two nitrogen-containing heterocycles (for example, quinoline, benzothiazole, or benzoxazole) having a squarylium group and a croconic methine group as a bonding chain or a cyanine-based dye bonded by a squarylium group or a croconic methine group, or the like can be preferably used. Note that, as the above-described metal complex dye, a dithiol metal complex-based dye, a metal phthalocyanine dye, a metal porphyrin dye, or a ruthenium complex dye is preferable, but is not limited thereto.

[0105] Further, in the present embodiment, an example in which an organic material is included in the photoelectric conversion layer 24 has been described, but this is not limiting. For example, the photoelectric conversion layer 24 can include an inorganic material such as crystalline silicon, amorphous silicon, microcrystalline silicon, crystalline selenium, amorphous selenium, a chalcopyrite compound, and a compound semiconductor. Examples of the chalcopyrite compound include CIGS (CuInGaSe), CIS (CuInSe2), CuInS2, CuAlS2, CuAlSe2, CuGaS2, CuGaSe2, AgAlS2, AgAlSe2, AgInS2, and AgInSe2, and the like. Examples of the compound semiconductor include CdSe, CdS, In2Se3, In2S3, Bi2Se3, Bi2S3, ZnSe, ZnS, PbSe, and PbS, and the like, in addition to a III-V compound semiconductor such as GaAs, InP, AlGaAs, InGaP, AlGaInP, and InGaAsP. The above-described inorganic material is used, for example, in a quantum dot shape.

[0106] Other layers can be provided between the photoelectric conversion layer 24 and the lower electrode 21 (for example, between the charge accumulation layer 23 and the photoelectric conversion layer 24) and between the photoelectric conversion layer 24 and the upper electrode 25. Specifically, for example, the charge accumulation layer 23, an electron-blocking film, the photoelectric conversion layer 24, a hole-blocking film, and a work function adjustment layer, and the like can be sequentially stacked from the lower electrode 21 side. Further, a bottom layer and a hole transport layer can be provided between the lower electrode 21 and the photoelectric conversion layer 24, and a buffer layer and an electron transport layer can be provided between the photoelectric conversion layer 24 and the upper electrode 25.

[0107] Like the lower electrode 21, the upper electrode 25 includes a conductive film having light-transmitting properties. In the imaging device 1 including the imaging element 10A as one pixel, the upper electrode 25 of each pixel can be separate, or the upper electrode 25 can be formed as an electrode common to each pixel. The thickness of the upper electrode 25 is, for example, 10 nm to 200 nm. Although not shown, a wiring is electrically connected to the upper electrode 25. A voltage is applied to the upper electrode 25.

[0108] The hydrogen-blocking layer 26 functions to suppress entry of hydrogen (H2) into the charge accumulation layer 23 and the photoelectric conversion layer 24. As described above, the hydrogen-blocking layer 26 is provided on the upper electrode 25 in the effective pixel region 110A. In the peripheral region 110B, the hydrogen-blocking layer 26 is stacked on the interlayer insulating layer 29 from the upper face of the upper electrode 25 via the side faces of the upper electrode 25, the photoelectric conversion layer 24, and the charge accumulation layer 23, and the upper face and the side faces of the insulating layer 22. The hydrogen-blocking layer 26 is formed so as to extend to the end portion of the peripheral region 110B, for example. Further, as described above, the interlayer insulating layer 29 is provided with the separation groove 29H. The separation groove 29H separates the effective pixel region 110A side and the peripheral region 110B side. The hydrogen-blocking layer 26 also covers the side face and the bottom face of this separation groove 29H.

[0109] Examples of the material constituting the hydrogen barrier layer 26 include insulating materials. Specifically, it is preferable to use a material having high light-transmitting property and sealing property. Examples of such a material include metal oxides such as aluminum oxide (AI2O3), silicon nitride, and silicon oxide containing carbon (SiOC). Alternatively, the hydrogen barrier layer 26 can use an oxide semiconductor such as ITO (indium tin oxide). In addition, it is preferable that the hydrogen barrier layer 26 contain, for example, less hydrogen than the insulating layer 22, or that the film itself contain no hydrogen at all. Furthermore, it is preferable that the hydrogen barrier layer 26 have less stress and also have ultraviolet light absorbing ability. Still further, it is preferable to form a film containing a small amount of moisture therein and to inhibit the entry of moisture (H2O). As described above, it is preferable to use aluminum oxide among the above-described materials as the material of the hydrogen barrier layer 26. The hydrogen barrier layer 26 includes a single-layer film formed by using the above-described material or a laminated film including two or more of the materials. The thickness of the hydrogen barrier layer 26 is, for example, 10 nm or more and 1000 nm or less.

[0110] The fixed charge layer 27 can be a film having a positive fixed charge or a film having a negative fixed charge. Materials for the film having a negative fixed charge include aluminum oxide, hafnium oxide (Hf02), zirconium oxide (ZrO), tantalum oxide (Ta205), titanium oxide (Ti02), lanthanum oxide (La203), praseodymium oxide (Pr203), cerium oxide (Ce02), neodymium oxide (Nd203), promethium oxide (Pm203), samarium oxide (Sm203), europium oxide (Eu203), gadolinium oxide (Gd203), terbium oxide (Tb203), dysprosium oxide (Dy203), holmium oxide (Ho203), thulium oxide (Tm203), ytterbium oxide (Yb203), lutetium oxide (Lu203), yttrium oxide (Y203), hafnium nitride (HfN), aluminum nitride (AIN), hafnium oxynitride (HfON), and aluminum oxynitride (AION), and the like.

[0111] The fixed charge layer 27 can have a configuration in which two or more types of films are laminated. Thus, for example, in the case where the film has a negative fixed charge, the function of the hole accumulation layer can be further enhanced.

[0112] The insulating layer 28 is provided on the fixed charge layer 27 formed on the first face (face 30S1) of the semiconductor substrate 30. In the through-holes 30H1, 30H2, and 30H3 in which the through electrodes 34A, 34B, and 34C are formed, the insulating layer 28 is provided between the fixed charge layer 27 and the through electrodes 34A, 34B, and 34C. The insulating layer 28 serves to electrically insulate the through electrodes 34 and the semiconductor substrate 30. Although the material of the insulating layer 28 is not particularly limited, the insulating layer 28 is formed, for example, by using silicon oxide, TEOS, silicon nitride, silicon oxynitride, and the like.

[0113] The interlayer insulating layer 29 is provided between the semiconductor substrate 30 (specifically, the insulating layer 28) and the photoelectric conversion section 20. The interlayer insulating layer 29 is provided with, for example, wirings such as pad sections 35A and 36A, pad sections 35B and 36B, pad sections 35C and 36C, and vias V1 and V2 in the layer. The pad sections 35A and 36A electrically connect the readout electrode 21A and the through electrode 34A. The pad sections 35B and 36B electrically connect the accumulation electrode 21B and the through electrode 34B. The pad sections 35C and 36C electrically connect the shield electrode 21C and the through electrode 34C. The vias V1 and V2 electrically connect the respective electrodes and the pad sections. As with the insulating layer 28, the interlayer insulating layer 29 includes, for example, a single layer film including one of silicon oxide, TEOS, silicon nitride, and silicon oxynitride, or a laminated film including two or more of the above.

[0114] The interlayer insulating layer 29 is further provided with a separation groove 29H that separates the effective pixel region 110A side and the peripheral region 110B side in the peripheral region 110B. Specifically, in a plan view, the separation groove 29H is provided between the opening H and the effective pixel region 110A. The opening H is provided on the pad electrode 61 arranged at the periphery of the peripheral region 110B. The side surface and the bottom surface of the separation groove 29H are covered with the hydrogen barrier layer 26 as described above. This, for example, suppresses the entry of hydrogen from the opening H into the charge accumulation layer 23 and the photoelectric conversion layer 24 via the interlayer insulating layer 29. In the present embodiment, the separation groove 29H is continuously provided in the peripheral region 110B and surrounds the effective pixel region 110A. Note that the separation groove 29H preferably extends to the first face (face 30S1) of the semiconductor substrate 30 via the interlayer insulating layer 29 and the insulating layer 28, but this is not limiting.

[0115] The first protective layer 51 is provided, for example, on the entire surface of the semiconductor substrate 30 including the effective pixel region 110A and the peripheral region 110B. Preferably, the first protective layer 51 is formed, for example, using a material that has light transmissivity and high sealing properties. Examples of such a material include insulating materials such as aluminum oxide, silicon nitride, and carbon-containing silicon oxide. In addition, preferably, as with the hydrogen barrier layer 26, the first protective layer 51 contains, for example, less hydrogen than the insulating layer 22, or the film itself does not contain any hydrogen. Furthermore, preferably, the first protective layer 51 has less stress, and also has ultraviolet light absorbing ability. Still further, preferably, the first protective layer 51 contains a small amount of moisture. Entry of moisture (H2O) is preferably suppressed. As described above, it is preferable to use aluminum oxide among the above-described materials as the material of the first protective layer 51. By forming the first protective layer 51 using aluminum oxide, the first protective layer 51 has a hydrogen blocking function, and the hydrogen barrier layer 26 and the first protective layer 51 can be formed in common.

[0116] Note that the first protective layer 51 can be formed using the same material as the insulating layer 28 and the interlayer insulating layer 29 described above. For example, the first protective layer 51 can be a single-layer film including one of silicon oxide, silicon nitride, and silicon oxynitride. Alternatively, the first protective layer 51 can be a laminated film including two or more of aluminum oxide, silicon nitride, a carbon-containing silicon oxide film, silicon oxide, and silicon oxynitride. The thickness of the first protective layer 51 is, for example, 100 nm to 1000 nm.

[0117] A chip-on-lens layer 52 is provided in the effective pixel region 110A on the first protective layer 51. In the chip-on-lens layer 52, a chip-on-lens 52L (a microlens) is formed, for example, for each unit pixel P. The chip-on-lens 52L condenses light from above on the respective light-receiving surfaces of the photoelectric conversion section 20, the inorganic photoelectric conversion section 32B, and the inorganic photoelectric conversion section 32R. Note that an optical member such as a color filter for controlling the spectrum can be provided below the chip-on-lens 52L. The material for the chip-on-lens layer 52 includes, in addition to silicon oxide, silicon nitride, and silicon oxynitride, aluminum oxide as an inorganic film for the hydrogen barrier layer 26. By forming the chip-on-lens layer 52 using aluminum oxide, the chip-on-lens layer 52 has a hydrogen blocking function in addition to a lens function. In addition, by forming the first protective layer 51 and the chip-on-lens layer 52 using aluminum oxide, the hydrogen barrier layer 26, the first protective layer 51, and the chip-on-lens layer 52 can be formed in common. In addition, the chip-on-lens layer 52 can be formed using, for example, a metal oxide-containing resin having metal nanoparticles dispersed in an organic film.

[0118] The semiconductor substrate 30 includes, for example, an n-type silicon (Si) substrate, and includes a p-well 31 in a predetermined region (for example, the pixel portion 1a). The second surface (surface 30S2) of the p-well 31 is provided with the transfer transistors TR1 trs , TR2 trs , and TR3 trs ; the amplification transistors TR1 amp and TR2 amp ; the reset transistors TR1 rst and TR2 rst ; and the selection transistors TR1 sel and TR2 sel , and the like. The peripheral region 110B of the semiconductor substrate 30 can be provided with, for example, a pixel readout circuit and a pixel drive circuit that constitute a logic circuit, and the like.

[0119] As described above, the imaging element 10A has a layout in which four pixels adjacent to each other share one floating diffusion FD1, one floating diffusion FD2, and one floating diffusion FD3. Figure 8A An example of a layout of the lower electrode 21 that constitutes the photoelectric conversion section 20 is shown.Figure 8B A perspective view of the layout of the lower electrode 21 is shown. Figure 8A A perspective view of the layout of the lower electrode 21 is shown. Figure 9A An example of the layout of the lower electrode 21 constituting the photoelectric conversion section 20 is shown. Figure 9B A perspective view of the layout of the lower electrode 21 is shown. Figure 9A A perspective view of the layout of the lower electrode 21 is shown. Figure 10 An example of the layout of the inorganic photoelectric conversion section 32B and various transistors associated therewith is shown. Figure 11 An example of the layout of the inorganic photoelectric conversion section R and various transistors associated therewith is shown. Figure 12 An example of a signal wiring for driving the accumulation electrode 21B in the photoelectric conversion section 20 is shown. Figure 13 to 15 Examples of wirings connected to the respective photoelectric conversion sections 20, 32B, and 32R and various transistors associated therewith are shown.

[0120] With regard to the photoelectric conversion section 20, four photoelectric conversion sections 20 adjacent to each other are connected to one floating diffusion section FD1. One reset transistor TR1 rst and a power supply line V dd are connected in series to the floating diffusion section FD1. Further, in addition thereto, one amplification transistor TR1 amp , one selection transistor TR1 sel , and a signal line (data output line) VSL1 are connected in series to the floating diffusion section FD1. In the photoelectric conversion section 20 according to the present embodiment, four accumulation electrodes 21B, reset transistors TR1 rst , amplification transistors TR1 amp , and selection transistors TR1 sel adjacent to each other are included in one set of control sections (first control section), which performs a readout operation and a reset operation of the four photoelectric conversion sections 20 adjacent to each other. One reset transistor TR1 rst , one amplification transistor TR1 amp , and one selection transistor TR1 sel are provided per pixel. In the case of reading out signal charges from the four photoelectric conversion sections 20 adjacent to each other, the first control section is used to perform the readout processing sequentially, for example, in a time-division manner.

[0121] In the inorganic photoelectric conversion section 32B, four photodiodes PD2 adjacent to each other are connected via four transfer transistors TR2 trs to one floating diffusion section FD2. Four transfer transistors TR2 trs are provided per pixel.

[0122] In the inorganic photoelectric conversion section 32R, as in the inorganic photoelectric conversion section 32B, four photodiodes PD3 adjacent to each other are connected via four transfer transistors TR3trs connected to a floating diffusion FD3. Four transfer transistors TR3 trs .

[0123] a reset transistor TR2 rst and a power supply line V dd is connected in series to a floating diffusion FD2. In addition to this, an amplification transistor TR2 amp , a selection transistor TR2 sel and a signal line (data output line) VSL2 are connected in series to the floating diffusion FD2. In the imaging device 10A having the pixel sharing structure as in the present embodiment, the inorganic photoelectric conversion section 32B and the inorganic photoelectric conversion section 32R use the transfer transistor TR2 trs and the transfer transistor TR3 trs , the reset transistor TR2 rst , the amplification transistor TR2 amp and the selection transistor TR2 sel to set a group of control sections (second control sections) that perform the readout operation and the reset operation of four inorganic photoelectric conversion sections 32B and 32R adjacent to each other. Each transfer transistor TR2 trs and each transfer transistor TR3 trs is provided for each pixel. The reset transistor TR2 rst is provided for each pixel. The amplification transistor TR2 amp is provided for each pixel. The selection transistor TR2 sel is provided for each pixel. In other words, the four inorganic photoelectric conversion sections 32B and 32R that constitute the stacked imaging device 10A of four pixels have a configuration in which a group of control sections (second control sections) is shared in addition to the shared transfer transistors TR2 trs and TR3 trs . In the case where the signal charge is read out from the floating diffusion FD2 corresponding to the four inorganic photoelectric conversion sections 32B adjacent to each other and the floating diffusion FD3 corresponding to the four inorganic photoelectric conversion sections 32R, the second control sections are used to sequentially perform the readout processing, for example, in a time-division manner.

[0124] Note that, in the present embodiment, the floating diffusions FD2 and FD3 shared by the four inorganic photoelectric conversion sections 32B and 32R adjacent to each other are provided at positions separated by one pixel from each other. Thus, the highly integrated imaging device 10A can be realized.

[0125] (1-2. Manufacturing method of imaging device)

[0126] The imaging element 10A according to the present embodiment can be manufactured, for example, as follows.

[0127] First, for example, the p-well 31 is formed as a well of the first conductivity type in the semiconductor substrate 30. The inorganic photoelectric conversion sections 32B and 32R, which are each of the second conductivity type (for example, n-type), are formed in the p-well 31. The p+ region is formed near the first surface (surface 30S1) of the semiconductor substrate 30.

[0128] For example, the n+ regions serving as the floating diffusion sections FD1 to FD3 are formed on the second surface (surface 30S2) of the semiconductor substrate 30, and then the gate insulating film 33 and the gate wiring layer 47 are formed. The gate wiring layer 47 includes the respective gates of the various transfer transistors TR1 trs , TR2 trs , and TR3 trs , the selection transistors TR1 sel and TR2 sel , the amplification transistors TR1 amp and TR2 amp , and the reset transistors TR1 rst and TR2 rst . Thus, the various transfer transistors TR1 trs , TR2 trs , and TR3 trs , the selection transistors TR1 sel and TR2 sel , the amplification transistors TR1 amp and TR2 amp , and the reset transistors TR1 rst and TR2 rst are formed. Further, the multilayer wiring layer 40 is formed on the second surface (surface 30S2) of the semiconductor substrate 30. The multilayer wiring layer 40 includes the wiring layers 41 to 43 and the insulating layer 44. The wiring layers 41 to 43 include the lower first contact 45 and the connection portion 41A.

[0129] As a base of the semiconductor substrate 30, for example, an SOI (Silicon on Insulator) substrate in which the semiconductor substrate 30, an embedded oxide film (not shown), and a holding substrate (not shown) are laminated is used. The embedded oxide film and the holding substrate are bonded to the first surface (surface 30S1) of the semiconductor substrate 30. After ion implantation, annealing processing is performed.

[0130] Next, the support substrate 70 on which the logic substrate 60 is formed is bonded to the second face (face 30S2) side (the multilayer wiring layer 40 side) of the semiconductor substrate 30 and is inverted. Subsequently, the semiconductor substrate 30 is separated from the embedded oxide film of the SOI substrate and the holding substrate to expose the first face (face 30S1) of the semiconductor substrate 30. The above steps can be performed using techniques used in conventional CMOS processes such as ion implantation and CVD (Chemical Vapor Deposition).

[0131] Next, the semiconductor substrate 30 is processed from the first face (face 30S1) side, for example, by dry etching, to form, for example, the ring-shaped through-holes 30H1, 30H2, 30H3, and 30H4. The depth of each of the through-holes 30H1 to 30H3 extends from the first face (face 30S1) to the second face (face 30S2) of the semiconductor substrate 30.

[0132] Next, a fixed charge layer 27 is formed on the first face (face 30S1) of the semiconductor substrate 30 and the side faces of the through-holes 30H by using, for example, an Atomic Layer Deposition (ALD) method. This forms the fixed charge layer 27 continuously on the first face (face 30S1) of the semiconductor substrate 30 and the side faces and bottom faces of the through-holes 30H1, 30H2, 30H3, and 30H4. Next, an insulating layer 28 is formed in the first face (face 30S1) of the semiconductor substrate 30 and the through-holes 30H1, 30H2, 30H3, and 30H4 of the fixed charge layer 27. Thereafter, an insulating film included in the interlayer insulating layer 29 is further formed on the insulating layer 28.

[0133] Next, a through-hole is formed in the insulating layer 28 formed in the through-holes 30H1, 30H2, and 30H3, for example, by dry etching. The through-hole reaches the connection portion 41A through the insulating film included in the interlayer insulating layer 29, the insulating layer 28, the fixed charge layer 27, and the insulating layer 44. Note that, in this case, the thickness of the insulating film included in the interlayer insulating layer 29 on the first face (face 30S1) is also reduced. Next, a conductive film is formed on the insulating film included in the interlayer insulating layer 29 and in the through-hole 27H, and a photoresist PR is formed at a predetermined position on the conductive film. Thereafter, the through-electrodes 34A, 34B, and 34C including the pad portions 35A, 35B, and 35C, respectively, on the first face (face 30S1) of the semiconductor substrate 30 are formed by etching and removing the photoresist PR.

[0134] Next, vias V2, pads 36, 36B, and 36C, and via V1 are formed on the insulating film constituting the interlayer insulating layer 29 and on the through electrodes 34A, 34B, and 34C, respectively. The surface of the interlayer insulating layer 29 is then planarized using CMP (Chemical Mechanical Polishing). Subsequently, a conductive film is formed on the interlayer insulating layer 29, and a photoresist PR is formed at predetermined locations on the conductive film. Then, the photoresist PR is etched and removed to form a readout electrode 21A, an accumulation electrode 21B, and a shielding electrode 21C. Next, an insulating layer 22 is formed on the interlayer insulating layer 29, the readout electrode 21A, the accumulation electrode 21B, and the shielding electrode 21C, and an opening 22H is provided on the readout electrode 21A. Subsequently, a charge accumulation layer 23, a photoelectric conversion layer 24, and an upper electrode 25 are formed on the insulating layer 22.

[0135] It should be noted that when using organic materials to form the charge accumulation layer 23 and other organic layers, it is preferable to form the charge accumulation layer 23 and other organic layers continuously in a vacuum step (in an in-situ vacuum process). Furthermore, the method for forming the photoelectric conversion layer 24 is not necessarily limited to vacuum evaporation. Other methods, such as spin coating or printing, can also be used.

[0136] Next, as Figure 16A As shown, for example, an alumina film 26B is formed in the effective pixel region 110A on the upper electrode 25 as a hard mask using a method such as physical vapor deposition (PVD), and the thickness of the alumina film 26B is, for example, 10 nm to 50 nm. It should be noted that the film formation method is not limited to this. For example, CVD or ALD methods can also be used. Examples of methods for forming films using PVD include EB (electron beam) evaporation and various sputtering methods (magnetron sputtering, RF-DC coupled bias sputtering, ECR sputtering, target-side sputtering, high-frequency sputtering), etc. Specifically, when the upper electrode 25 has a large surface roughness, it is preferable to use the CVD / ALD method, which has excellent coverage, to form the film. However, the film formation rate of the CVD / ALD method is significantly lower than that of the PVD method. Therefore, the PVD method is preferred, provided that it can adequately cover the upper electrode 25 in the PVD process. Next, the alumina film 26B is patterned and a hard mask is formed using, for example, photolithography. Note that the following... Figure 16B An example of removing the photoresist PR is shown, but the photoresist can be retained after patterning the alumina film 26B, and the next step can be performed.

[0137] Next, as Figure 16B As shown, the charge accumulation layer 23, photoelectric conversion layer 24, and upper electrode 25 formed in the peripheral region 110B are etched using an alumina film 26B as a hard mask. Subsequently, the insulating layer 22 is etched. Next, a photoresist PR is patterned on the insulating layer 22, the alumina film 26B, and the interlayer insulating layer 29. Then, for example, as... Figure 16C As shown, a separation groove 29H is formed in the peripheral region 110B. The separation groove 29H surrounds the effective pixel region 110A and extends through the interlayer insulating layer 29 and the insulating layer 28.

[0138] Next, as Figure 16D As shown, an aluminum oxide film 26A is formed on the entire top of the aluminum oxide film 26B and on the interlayer insulating layer 29 using, for example, a PVD method, with the thickness of the aluminum oxide film 26A being, for example, 50 nm to 1000 nm. The interlayer insulating layer 29 includes the sides of the upper electrode 25, the photoelectric conversion layer 24, the charge accumulation layer 23, and the insulating layer 22, as well as the sides and bottom of the separation trench 29H. Thus, a hydrogen barrier layer 26 comprising aluminum oxide films 26A and 26B is formed. It should be noted that, like the aluminum oxide film 26B, the aluminum oxide film 26A can be formed using either a CVD method or an ALD method. For example, when there is a large height difference between the charge accumulation layer 23, the photoelectric conversion layer 24, and the upper electrode 25, the CVD / ALD method, which has excellent coverage properties, is preferred. When a high film formation rate and warpage (stress) adjustment of the semiconductor substrate 30 are preferred, the PVD method is preferred. Furthermore, the PVD method and the CVD / ALD method can be combined to form a hydrogen barrier layer 26 comprising a stacked film. Next, a first protective layer 51 is formed on the hydrogen barrier layer 26, and the separation trench 29H is filled. Finally, an on-chip lens layer 52 is formed on the first protective layer 51. As described above, the process is complete. Figure 1 The image sensor 10A shown is shown.

[0139] When light enters the photoelectric conversion unit 20 via the on-chip lens 52L in the imaging element 10A, the light sequentially passes through the photoelectric conversion unit 20 and the inorganic photoelectric conversion units 32B and 32R. As the light passes through the photoelectric conversion unit 20 and the inorganic photoelectric conversion units 32B and 32R, photoelectric conversion is performed on the green, blue, and red colored light, respectively. The operation of acquiring signals of various colors is described below.

[0140] (Green signal is acquired through photoelectric conversion unit 20)

[0141] First, the green light in the light that has been incident on the imaging element 10A is selectively detected (absorbed) by the photoelectric conversion unit 20 and converted into photoelectric light.

[0142] The photoelectric conversion section 20 is connected to the gate Gamp of the amplification transistor AMP and the floating diffusion section FD1 via the through electrode 34A. Therefore, the electrons in the electron-hole pair generated by the photoelectric conversion section 20 are extracted from the lower electrode 21 side, transmitted to the second face (face 30S2) side of the semiconductor substrate 30 via the through electrode 34, and accumulated in the floating diffusion section FD1. Meanwhile, the amplification transistor AMP modulates the amount of charge generated by the photoelectric conversion section 20 into a voltage.

[0143] In addition, the reset gate Grst of the reset transistor TR1rst is arranged next to the floating diffusion section FD1. Therefore, the reset transistor TR1rst resets the charge accumulated in the floating diffusion section FD1.

[0144] Here, the photoelectric conversion section 20 is connected not only to the amplification transistor TR1amp but also to the floating diffusion section FD1 via the through electrode 34A, thereby enabling the reset transistor TR1rst to easily reset the charge accumulated in the floating diffusion section FD1.

[0145] On the contrary, in the case where the through electrode 34A and the floating diffusion section FD1 are not connected, it is difficult to reset the charge accumulated in the floating diffusion section FD1. The charge is pulled out to the upper electrode 25 side by applying a high voltage. The photoelectric conversion layer 24 can thus be damaged. In addition, a structure that enables resetting in a short time causes an increase in dark-time noise and leads to a trade-off. Therefore, such a structure is difficult.

[0146] Figure 17 An operation example of the image pickup element 10A is shown. (A) shows the potential at the accumulation electrode 21B, (B) shows the potential at the floating diffusion section FD1 (readout electrode 21A), and (C) shows the potential at the gate (Gsel) of the reset transistor TR1rst. In the image pickup element 10A, a voltage is applied to the readout electrode 21A and the accumulation electrode 21B, respectively.

[0147] In the image pickup element 10A, in the accumulation period, the driving circuit applies the potential V1 to the readout electrode 21A and the potential V2 to the accumulation electrode 21B. Here, it is assumed that the potentials V1 and V2 satisfy V2 > V1. This causes the charge (here, electrons) generated by photoelectric conversion to be attracted to the accumulation electrode 21B and accumulated in the region of the charge accumulation layer 23 opposite to the accumulation electrode 21B (accumulation period). In addition, as photoelectric conversion proceeds, the potential value in the region of the charge accumulation layer 23 opposite to the accumulation electrode 21B becomes more negative. Note that holes are transmitted to the driving circuit from the upper electrode 25.

[0148] In the imaging element 10A, a reset operation is performed in the second part of the accumulation period. Specifically, at time t1, the scanning section changes the voltage of the reset signal RST from the low level to the high level. Thus, in the unit pixel P, the reset transistor TR1rst is turned on. As a result, the voltage of the floating diffusion section FD1 is set to the power supply voltage VDD, and the voltage of the floating diffusion section FD1 is reset (reset period).

[0149] After the reset operation is completed, the charge is read out. Specifically, at time t2, the drive circuit applies the potential V3 to the readout electrode 21A, and applies the potential V4 to the accumulation electrode 21B. Here, it is assumed that the potentials V3 and V4 satisfy V3 < V4. This causes the charge (here, an electron) accumulated in the region corresponding to the accumulation electrode 21B to be read out from the readout electrode 21A to the floating diffusion section FD1. In other words, the charge accumulated in the charge accumulation layer 23 is read out by the control section (transfer period).

[0150] After the readout operation is completed, the drive circuit again applies the potential V1 to the readout electrode 21A, and applies the potential V2 to the accumulation electrode 21B. This causes the charge (here, an electron) generated by the photoelectric conversion to be attracted to the accumulation electrode 21B and accumulated in the region of the photoelectric conversion layer 24 opposite to the accumulation electrode 21B (accumulation period).

[0151] (Obtaining blue and red signals by inorganic photoelectric conversion sections 32B and 32R)

[0152] Next, the inorganic photoelectric conversion section 32B and the inorganic photoelectric conversion section 32R sequentially absorb blue light and red light, respectively, from among the light that has passed through the photoelectric conversion section 20, and photoelectrically convert them. In the inorganic photoelectric conversion section 32B, the electron corresponding to the incident blue light is accumulated in the n region of the inorganic photoelectric conversion section 32B, and the accumulated electron is transferred to the floating diffusion section FD2 through the transfer transistor TR2 trs Similarly, in the inorganic photoelectric conversion section 32R, the electron corresponding to the incident red light is accumulated in the n region of the inorganic photoelectric conversion section 32R, and the accumulated electron is transferred to the floating diffusion section FD3 through the transfer transistor TR3 trs

[0153] (1-3. Action and effect)

[0154] ​As described above, in recent years, since a stacked image pickup element is capable of extracting R / G / B signals from one pixel and does not require demosaicing processing, a stacked image pickup element is used in an image pickup device such as a CCD image sensor or a CMOS image sensor, so that false colors do not occur. The stacked image pickup element has a configuration in which an organic photoelectric conversion portion including an organic photoelectric conversion layer is stacked on a semiconductor substrate in which a photodiode is embedded and formed. The organic photoelectric conversion layer includes a semiconductor material.

[0155] However, in the stacked image pickup element as described above, charges generated by the organic photoelectric conversion portion are directly accumulated in the floating diffusion layer FD. Therefore, it is difficult to completely deplete the organic photoelectric conversion portion, which increases kTC noise, increases random noise, and deteriorates the quality of a captured image. Therefore, an image pickup element having a charge accumulation electrode has been developed as a stacked image pickup element capable of completely depleting the organic photoelectric conversion portion. The charge accumulation electrode is disposed on the side of one electrode (for example, the first electrode) of a pair of electrodes (the first electrode and the second electrode) facing each other with the organic photoelectric conversion layer interposed therebetween in the organic photoelectric conversion portion provided above the semiconductor substrate. The charge accumulation electrode is provided separately from the first electrode. The charge accumulation electrode is disposed to face the organic photoelectric conversion layer with an insulating layer interposed therebetween.

[0156] In the image pickup element, the organic photoelectric conversion layer has a structure in which, for example, a lower semiconductor layer and an upper photoelectric conversion layer are stacked. The lower semiconductor layer is formed by using an oxide semiconductor material. The upper photoelectric conversion layer is formed by using an organic semiconductor material. Therefore, it is possible to prevent recombination of charges accumulated in the organic photoelectric conversion layer and improve the transfer efficiency to the first electrode. However, the oxide semiconductor material included in the lower semiconductor layer is easily reduced by hydrogen. This can cause oxygen defects and reduce the operation stability.

[0157] On the other hand, in the imaging device 10A according to the present embodiment, the separation groove 29H that separates the interlayer insulating layer 29 provided between the semiconductor substrate 30 and the photoelectric conversion section 20 is provided in the peripheral region 110B and surrounds the effective pixel region 110A. The side surface and the bottom surface of the separation groove 29H are covered with the hydrogen barrier layer 26. The hydrogen barrier layer 26 is formed using, for example, aluminum oxide. The hydrogen barrier layer 26 covers, for example, the upper surface of the upper electrode 25 that extends to the effective pixel region 110A, and the side surfaces of the upper electrode 25, the photoelectric conversion layer 24, the charge accumulation layer 23, and the insulating layer 22. The hydrogen barrier layer 26 is directly stacked on the interlayer insulating layer 29 in the peripheral region 110B. This suppresses entry of hydrogen (H2) into the charge accumulation layer 23 and the photoelectric conversion layer 24 from the upper electrode 25 side and an opening H provided on, for example, the pad electrode 61 via the interlayer insulating layer 29, and suppresses entry of hydrogen (H2) into the charge accumulation layer 23 and the photoelectric conversion layer 24 from the lower electrode 21 side.

[0158] As described above, in the present embodiment, the separation groove 29H is provided in the peripheral region 110B and surrounds the effective pixel region 110A. The separation groove 29H separates the interlayer insulating layer 29 provided between the semiconductor substrate 30 and the photoelectric conversion section 20. The side surface and the bottom surface of the separation groove 29H are covered with the hydrogen barrier layer 26. This suppresses entry of hydrogen (H2) into the charge accumulation layer 23 and the photoelectric conversion layer 24 via the interlayer insulating layer 29. For example, fewer oxygen defects occur in the charge accumulation layer 23, thereby improving the operation stability. In other words, the reliability of the imaging device 10A and the imaging device 1 including the imaging device 10A can be improved.

[0159] In addition, in the present embodiment, the hydrogen barrier layer 26 is formed by using a material that can form a film containing a small amount of moisture in addition to containing a small amount of hydrogen. This suppresses entry of moisture (H2O) into the photoelectric conversion layer 24, and can prevent the photoelectric conversion layer 24 from being deteriorated.

[0160] Next, a second embodiment and modification examples 1 to 7 will be described. Note that components corresponding to those in the imaging device 10A according to the first embodiment are denoted by the same reference numerals, and the description thereof will be omitted.

[0161] <2. Modification Example 1>

[0162] Figure 18 A cross-sectional configuration of an imaging device (imaging device 10B) according to a modification example (modification example 1) of the present disclosure is schematically shown. Figure 19 A cross-sectional configuration of an imaging device (imaging device 10B) according to a modification example (modification example 1) of the present disclosure is schematically shown. Figure 18 An example of a planar configuration of the imaging device 10B is shown. Note that Figure 18 An example of a planar configuration of the imaging device 10B is shown. Note that Figure 19The cross-section shown is taken by line II-II. Similar to the first embodiment described above, the imaging element 10B is included, for example, in a pixel (unit pixel P) of an imaging device 1, such as a CMOS image sensor, included in an electronic device such as a digital camera or camcorder. The imaging element 10B according to this variation differs from the imaging element 10A according to the first embodiment described above in that, as Figure 18 and Figure 19 As shown, the peripheral area 110B is provided with two separation grooves (separation groove 29H1 and separation groove 29H2), which separate the interlayer insulating layer 29 and surround the effective pixel area 110A.

[0163] In this way, multiple separation trenches 29H can be provided surrounding the effective pixel area 110A. Therefore, hydrogen (H2) can be further suppressed from entering the charge accumulation layer 23 from the lower electrode 21 side. This can further improve the reliability of the imaging element 10B and the imaging device 1 including the imaging element 10B.

[0164] <3. Variation Example 2>

[0165] Figure 20 The cross-sectional structure of the imaging element (imaging element 10C) according to a modified example (modification 2) of the present disclosure is schematically shown. Figure 21 schematically shown Figure 20 An example of the planar structure of the imaging element 10C is shown. It should be noted that... Figure 20 It shows along Figure 21 The cross-section shown is taken by line III-III. Similar to the first embodiment described above, the imaging element 10C is included, for example, in a pixel (unit pixel P) of an imaging device 1, such as a CMOS image sensor, included in an electronic device such as a digital camera or camcorder. The imaging element 10C according to this variation differs from the imaging element 10A according to the first embodiment described above in that, as Figure 20 and Figure 21 As shown, the separation groove 29H is configured to surround the opening H, which is formed on each of the plurality of pad electrodes 61 arranged in the peripheral region 110B.

[0166] In addition, although Figure 21 An example is shown in which a separation groove 29H is provided, individually surrounding a plurality of (here, six) openings H formed on a plurality of respective pad electrodes 61, but is not limited thereto. For example, as Figure 22 As shown, the separation groove 29H can collectively surround, for example, a plurality of openings H arranged along one side of the peripheral region 110B.

[0167] Hydrogen (H2) enters the charge accumulation layer 23 and photoelectric conversion layer 24 via the interlayer insulating layer 29, primarily from the side of the opening H that extends from the on-chip lens layer 52 to the pad electrode 61, which is disposed on the pad electrode 61. Therefore, the separation trench 29H is provided in a manner that surrounds the opening H. The separation trench 29H separates the interlayer insulating layer 29. Therefore, the entry of hydrogen (H2) into the charge accumulation layer 23 from the lower electrode 21 side can be largely suppressed. This improves the reliability of the imaging element 10C and the imaging device 1 including the imaging element 10C.

[0168] <4. Variation Example 3>

[0169] Figure 23 The cross-sectional structure of the imaging element (imaging element 10D) according to a modified example (modification 3) of the present disclosure is schematically shown. Figure 24 schematically shown Figure 23 An example of the planar construction of the imaging element 10D is shown. It should be noted that... Figure 23 It shows along Figure 24 The cross-section shown is taken by line IV-IV. Similar to the first embodiment described above, the imaging element 10D is, for example, included in a pixel (unit pixel P) of an imaging device 1, such as a CMOS image sensor, included in an electronic device such as a digital camera or camcorder. The imaging element 10D according to this modification is, for example, a combination of the first embodiment and modification 2. Figure 23 and Figure 24 As shown, the imaging element 10D has separation grooves (separation groove 29H3 and separation groove 29H4) around the effective pixel area 110A and around the opening H. Separation grooves 29H3 and separation groove 29H4 separate the interlayer insulating layer 29 in the peripheral area 110B. The opening H is formed on a plurality of corresponding pad electrodes 61.

[0170] In this way, separation trenches 29H3 and 29H4 respectively surround the effective pixel area 110A and the opening H on the pad electrode 61. Therefore, hydrogen (H2) can be further suppressed from entering the charge accumulation layer 23 from the lower electrode 21 side. This can further improve the reliability of the image sensor 10D and the imaging device 1 including the image sensor 10D.

[0171] <5. Variation Example 4>

[0172] Figure 25The cross-sectional structure of an imaging element (image element 10E) according to a variation (variation 4) of the present disclosure is schematically shown. Similar to the first embodiment described above, the image element 10E is included, for example, in a pixel (unit pixel P) of an imaging device 1, such as a CMOS image sensor, included in an electronic device such as a digital camera or camcorder. The difference between the image element 10E according to this variation and the image element of the first embodiment described above is that the separation groove 29H extends to the logic substrate 60. The separation groove 29H separates the interlayer insulating layer 29.

[0173] In the first embodiment and variations 1 to 3 described above, although an example in which the separation trench 29H extends to the first surface (surface 30S1) of the semiconductor substrate 30 is described, the depth (D1) of the separation trench 29H is not limited thereto. The depth (D1) of the separation trench 29H may be less than the depth (D2) of the opening H from the surface (surface 29S) of the interlayer insulating layer 29 to the pad electrode 61, or, as in this variation, greater than the depth (D2) of the opening H. In addition, in the first embodiment and variations 1 to 3 described above, although the bottom surface of the separation trench 29H is the first surface (surface 30S1) of the semiconductor substrate 30, it may also be formed, for example, inside the semiconductor substrate 30.

[0174] In this way, the separation trench 29H that separates the interlayer insulating layer 29 can be formed to extend to the logic substrate 60. Therefore, hydrogen (H2) can be suppressed from entering the charge accumulation layer 23, etc., from the opening H, for example via the insulating layer 44, through-holes 34H1, 34H2, and 34H3. Through-electrodes 34A, 34B, and 34C extend through through-holes 34H1, 34H2, and 34H3. This further improves the reliability of the imaging element 10E and the imaging device 1 including the imaging element 10E.

[0175] Additionally, for example, such as Figure 26 As shown in the image sensor 10F, a separate separation groove 40H can be provided, which separates the insulating layer 44 constituting the multilayer wiring layer 40 into an effective pixel area 110A side and a peripheral area 110B side. This allows the image sensor 10F to have the same effect as the image sensor 10E. It should be noted that, similar to the separation groove 29H, an insulating layer 48 is preferably formed on the side and bottom surfaces of the separation groove 40H. The insulating layer 48 includes, for example, aluminum oxide. Furthermore, it is preferable to fill the separation groove 40H with an insulating layer 49. Examples of materials used for the insulating layer 49 include the same material as the first protective layer 51.

[0176] <6. Variation Example 5>

[0177] Figure 27A part of the cross-sectional configuration of the image pickup element (image pickup element 10G) according to a modification (modification 5) of the present disclosure is schematically shown. As with the first embodiment described above, the image pickup element 10G is included in, for example, one pixel (unit pixel P) of an image pickup device 1 such as a CMOS image sensor included in an electronic device such as a digital camera or a video camera. The image pickup element 10G according to the present embodiment is further provided with a hydrogen barrier layer 81 (second hydrogen barrier layer) in a lower layer of the lower electrode 21 on the interlayer insulating layer 29, for example. In addition, the insulating layer 22, the charge accumulation layer 23, the photoelectric conversion layer 24, and the upper electrode 25 of the image pickup element 10G are formed to have the same end surface. The image pickup element 10G according to the present modification differs from the image pickup element 10A according to the first embodiment in the above two points.

[0178] As described above, the hydrogen barrier layer 81 is provided on the interlayer insulating layer 29, for example, in the entire effective pixel region 110A and the peripheral region 110B. The hydrogen barrier layer 81 functions to suppress entry of hydrogen (H2) from below the charge accumulation layer 23. Examples of the material constituting the hydrogen barrier layer 81 include insulating materials. Specifically, it is preferable to use a material having light transmissivity and high sealing properties. Examples of such a material include aluminum oxide, silicon nitride, and a carbon-containing silicon oxide film, and the like. In addition, it is preferable that, for example, the hydrogen content in the hydrogen barrier layer 81 is less than the hydrogen content in the insulating layer 22, or that the film itself does not contain any hydrogen. Furthermore, the stress of the hydrogen barrier layer 81 is small. As described above, it is preferable to use aluminum oxide among the above-described materials as the material of the hydrogen barrier layer 81. The thickness of the hydrogen barrier layer 81 is, for example, 10 nm or more and 1000 nm or less.

[0179] As described above, in the present modification, the hydrogen barrier layer 81 is further provided in the lower layer of the lower electrode 21. Therefore, entry of hydrogen (H2) from the lower electrode 21 side into the charge accumulation layer 23 can be further suppressed. Thus, the reliability of the image pickup element 10G and the image pickup device 1 including the same can be further improved.

[0180] Note that, in the present modification, although an example in which the hydrogen barrier layer 81 provided in the lower layer of the lower electrode 21 is provided directly below the lower electrode 21 is described, it is not limited thereto. The hydrogen barrier layer 81 can be provided as long as it is provided between the semiconductor substrate 30 and the lower electrode 21. For example, the hydrogen barrier layer 81 can be formed in the interlayer insulating layer 29.

[0181] <7. Modification 6>

[0182] Figure 28A part of the cross-sectional configuration of an imaging element (imaging element 10H) according to a modification (modification 6) of the present disclosure is schematically shown. As with the above-described first embodiment, the imaging element 10H is included in, for example, one pixel (unit pixel P) of an imaging device 1 such as a CMOS image sensor included in an electronic device such as a digital camera or a video camera. The imaging element 10H is provided with an insulating layer 92 that electrically insulates the lower electrode 21 and the charge accumulation layer 23, like the insulating layer in the above-described first embodiment, which includes a material similar to the hydrogen blocking layer 26 and the hydrogen blocking layer 81. In addition, in the imaging element 10H, the insulating layer 92 is formed on, for example, the effective pixel region 110A and the peripheral region 110B. The imaging element 10H according to the present modification differs from the imaging element 10A according to the first embodiment in the above two points.

[0183] The insulating layer 92 functions to electrically insulate the accumulation electrode 21B and the shield electrode 21C from the charge accumulation layer 23, and to suppress entry of hydrogen (H2) from below the charge accumulation layer 23. Preferably, like the hydrogen blocking layer 26 and the hydrogen blocking layer 81, the material that constitutes the insulating layer 92 has light transmissivity and high sealing properties. Furthermore, a dense film having fewer defects is preferable. Examples of such a material include aluminum oxide.

[0184] As described above, in the present modification, the insulating layer 92 that electrically insulates the accumulation electrode 21B and the shield electrode 21C from the charge accumulation layer 23 is formed using, for example, aluminum oxide. This causes the insulating layer 92 to have the function of a hydrogen blocking layer. Entry of hydrogen (H2) from below the charge accumulation layer 23 can be suppressed. Thus, the reliability of the imaging element 10H and the imaging device 1 including the same can be further improved.

[0185] <8. Second Embodiment>

[0186] Figure 29 An example of the cross-sectional configuration of an imaging element (imaging element 10I) according to a second embodiment of the present disclosure is shown. As with the above-described first embodiment, the imaging element 10I is included in, for example, one pixel (unit pixel P) of an imaging device 1 such as a CMOS image sensor included in an electronic device such as a digital camera or a video camera. The imaging device 1 has an effective pixel region 110A and a peripheral region 110B. A plurality of pixels are provided in the effective pixel region 110A. The peripheral region 110B is provided around the effective pixel region 110A. For example, a peripheral circuit such as a row scanning section 131 is formed in the peripheral region 110B. The imaging element 10I is formed in each of the plurality of pixels.

[0187] In addition to the components of the imaging element 10A according to the first embodiment described above, the imaging element 10I according to this embodiment also includes a through electrode 34D, which is located in the peripheral region 110B, for example, closer to the effective pixel region 110A than the separation groove 29H. The separation groove 29H separates the interlayer insulating layer 29. The through electrode 34D penetrates the semiconductor substrate 30. The through electrode 34D is electrically connected to the pad portion 36D via the pad portion 35D and the through-hole V2. Figure 29 As shown, an opening 51H1 is provided on the pad portion 36D. The opening 51H1 extends through the first protective layer 51 and the hydrogen barrier layer 26, exposing the pad portion 36D. The sides and bottom of the opening 51H1 are covered by wiring 53. Wiring 53 connects to the pad portion 36D on the bottom surface of the opening 51H1 and forms a guard ring 55. Wiring 53 also extends on the first protective layer 51. Wiring 53 connects to the upper electrode 25 on the bottom surface of the opening 51H2 that extends through the first protective layer 51 on the upper electrode 25. Therefore, the upper electrode 25 is electrically connected to the through electrode 34D via wiring 53, pad portion 36D, via V2, and pad portion 35D. A voltage is applied to the upper electrode 25. In addition, these upper electrodes 25, wiring 53, pad portion 36D, through hole V2, pad portion 35D and through electrode 34D serve as the transmission path for the charge (hole) generated by the photoelectric conversion unit 20.

[0188] In this embodiment, a second protective layer 54 is also provided on the first protective layer 51 and the wiring 53. Openings 51H1 and 51H2 are filled by this second protective layer 54. The material used for the second protective layer 54 includes the same material as the first protective layer 51. A light-shielding film 56 is provided on the second protective layer 54 in the peripheral region 110B. Examples of materials used for the light-shielding film 56 include tungsten (W), titanium (Ti), titanium nitride (TiN), or aluminum (Al). The light-shielding film 56 is, for example, constructed as a W / TiN / Ti laminate or a single layer of W. The thickness of the light-shielding film 56 is, for example, 50 nm or more and 400 nm or less. As in the imaging element 10A, an on-chip lens layer 52 is provided on the second protective layer 54 and the light-shielding film 56.

[0189] As described above, in this embodiment, a protective ring 55 is formed in the peripheral region 110B. Therefore, the entry of hydrogen (H2) or moisture (H2O) from the outside can be further suppressed. This further improves the reliability of the imaging element 10I and the imaging device 1 including the imaging element 10I.

[0190] In addition, although Figure 29 An example is shown in which a separation groove 29H is provided on the outside of the protective ring 55; however, for example, as... Figure 30As shown, the separation groove 29H can also be provided on the inner side (effective pixel region 110A side) of the guard ring 55.

[0191] <9. Modification 7>

[0192] Figure 31 Another example of a layout of the lower electrode 21 configuring the photoelectric conversion section 20 of the imaging device 10A according to a modification (modification 7) of the present disclosure is shown. Figure 32 Another example of a layout of the inorganic photoelectric conversion section 32B of the imaging device 10A according to a modification of the present disclosure and various transistors related thereto is shown. Figure 33 Another example of a layout of the inorganic photoelectric conversion section R of the imaging device 10A according to a modification of the present disclosure and various transistors related thereto is shown. Figure 34 to 37 Another example of a layout of the inorganic photoelectric conversion section R of the imaging device 10A according to a modification of the present disclosure and various transistors related thereto is shown. Figure 31 to 37 As shown, the imaging device 10A according to the first embodiment described above can be formed as a stacked imaging device having no pixel sharing structure or a stacked imaging device having a so-called single-pixel structure.

[0193] <10. Application Example>

[0194] (Application Example 1)

[0195] Figure 38 The overall configuration of an imaging device (imaging device 1) including the imaging device 10A (or imaging devices 10B to 10D) explained in the above first manner (or second embodiment and modifications 1 to 7) for each pixel is shown. The imaging device 1 is a CMOS image sensor. The imaging device 1 includes a pixel section 1a as an imaging region and a peripheral circuit section 130 in a peripheral region of the pixel section 1a on a semiconductor substrate 30. The peripheral circuit section 130 includes, for example, a row scanning section 131, a horizontal selection section 133, a column scanning section 134, and a system control section 132. Note that the pixel section 1a corresponds to the effective pixel region 110A in the above first embodiment and the like.

[0196] The pixel section 1a includes, for example, a plurality of unit pixels P (each unit pixel P corresponds to the imaging device 10) arranged two-dimensionally in a matrix shape. These unit pixels P are provided with, for example, a pixel drive line Lread (specifically, a row selection line and a reset control line) in each pixel row, and a vertical signal line Lsig in each pixel column. The pixel drive line Lread transmits a drive signal for reading out a signal from a pixel, respectively. One end of each pixel drive line Lread is connected to an output terminal of the row scanning section 131 corresponding to each row.

[0197] The row scanning section 131 is a pixel drive section including a shift register and an address decoder, and the like, and drives each unit pixel P of the pixel section 1a, for example, on a row-by-row basis. The signals output from each unit pixel P in the pixel row selectively scanned from the row scanning section 131 are supplied to the horizontal selection section 133 through each vertical signal line Lsig. The horizontal selection section 133 includes an amplifier and a horizontal selection switch provided for each vertical signal line Lsig, and the like.

[0198] The column scanning section 134 includes a shift register and an address decoder, and the like, and the column scanning section 134 drives each horizontal selection switch of the horizontal selection section 133 while scanning the horizontal selection switch, in sequence. The selective scanning by this column scanning section 134 causes the signals of each pixel transmitted through each vertical signal line Lsig to be output to the horizontal signal line 135 in sequence, and transmitted to the outside of the semiconductor substrate 30 through the horizontal signal line 135.

[0199] The circuit section including the row scanning section 131, the horizontal selection section 133, the column scanning section 134, and the horizontal signal line 135 can be formed directly on the semiconductor substrate 30 or can be provided in an external control IC. In addition, these circuit sections can be formed on another substrate connected by a cable or the like.

[0200] The system control section 132 receives data such as a clock and an instruction on an operation mode provided from the outside of the semiconductor substrate 30, and outputs data such as internal information on the imaging device 1. The system control section 132 also includes a timing generator that generates various timing signals, and controls the drive of the peripheral circuit such as the row scanning section 131, the horizontal selection section 133, and the column scanning section 134, based on the various timing signals generated by the timing generator.

[0201] (Applicable Example 2)

[0202] The above-described imaging device 1 is applicable, for example, to any type of electronic equipment having an imaging function. The electronic equipment includes a camera system such as a digital camera or a video camera, a mobile phone having an imaging function, and the like. Figure 39A schematic configuration of an electronic device 2 (camera) is shown as an example. The electronic device 2 is, for example, a video camera capable of capturing still images or moving images. The electronic device 2 includes an imaging device 1, an optical system (optical lens) 210, a shutter device 211, a drive section 213 that drives the imaging device 1 and the shutter device 211, and a signal processing section 212.

[0203] The optical system 210 guides image light (incident light) from an object to a pixel section 1a of the imaging device 1. The optical system 210 can include a plurality of optical lenses. The shutter device 211 controls a light exposure period and a light blocking period of the imaging device 1. The drive section 213 controls a transfer operation of the imaging device 1 and a shutter operation of the shutter device 211. The signal processing section 212 performs various signal processing on a signal output from the imaging device 1. An image signal Dout that has undergone the signal processing is stored in a storage medium such as a memory or the like, or is output to a monitor or the like.

[0204] Further, the above-described imaging device 1 is also applicable to the following electronic devices (capsule endoscope 10100 and a mobile body such as a vehicle).

[0205] <11. Application Example>

[0206] <Application Example of In-Vivo Information Acquisition System>

[0207] Further, a technology according to the present disclosure (the present technology) is applicable to various products. For example, the technology according to the present disclosure can be applied to an in-vivo information acquisition system.

[0208] Figure 40 is a block diagram showing an example of a schematic configuration of an in-vivo information acquisition system of a patient using a capsule endoscope, to which a technology according to an embodiment of the present disclosure (the present technology) is applicable.

[0209] An in-vivo information acquisition system 10001 includes a capsule endoscope 10100 and an external control device 10200.

[0210] The patient swallows the capsule endoscope 10100 at the time of examination. The capsule endoscope 10100 has an imaging function and a wireless communication function, and the capsule endoscope 10100 successively captures images (hereinafter referred to as in-vivo images) in an organ such as a stomach or an intestine at predetermined intervals while moving within the organ by peristaltic motion for a certain period of time until the patient naturally excretes the capsule endoscope 10100. Then, the capsule endoscope 10100 successively transmits information of the in-vivo images to the external control device 10200 outside the body by wireless transmission.

[0211] The external control device 10200 integrally controls the operation of the in-vivo information acquisition system 10001. Further, the external control device 10200 receives information of an in-vivo image transmitted from the capsule endoscope 10100, and generates image data for displaying the in-vivo image on a display device (not shown) on the basis of the received information of the in-vivo image.

[0212] In the in-vivo information acquisition system 10001, in this way, it is possible to acquire an in-vivo image obtained by imaging a state in a patient's body at any time in a period from after the capsule endoscope 10100 is ingested to the time when it is excreted.

[0213] Hereinafter, the configuration and functions of the capsule endoscope 10100 and the external control device 10200 will be described in more detail.

[0214] The capsule endoscope 10100 includes a capsule-shaped casing 10101 in which a light source unit 10111, an imaging unit 10112, an image processing unit 10113, a wireless communication unit 10114, a power supply unit 10115, a power source unit 10116, and a control unit 10117 are accommodated.

[0215] The light source unit 10111 includes, for example, a light source such as a light emitting diode (LED), and the light source unit 10111 irradiates the imaging field of view of the imaging unit 10112 with light.

[0216] The imaging unit 10112 includes an imaging element and an optical system including a plurality of lenses disposed in front of the imaging element. Reflected light (hereinafter referred to as observation light) of light irradiated onto a body tissue as an observation target is condensed by the optical system and is incident on the imaging element. In the imaging unit 10112, the imaging element photoelectrically converts the incident observation light, thereby generating an image signal corresponding to the observation light. The image signal generated by the imaging unit 10112 is supplied to the image processing unit 10113.

[0217] The image processing unit 10113 includes a processor such as a central processing unit (CPU) or a graphics processing unit (GPU), and performs various signal processing on the image signal generated by the imaging unit 10112. The image processing unit 10113 supplies the image signal subjected to the signal processing to the wireless communication unit 10114 as raw data.

[0218] The wireless communication unit 10114 performs predetermined processing (e.g., modulation processing) on the image signal that has been subjected to signal processing by the image processing unit 10113, and transmits the resulting image signal to the external control device 10200 via the antenna 10114A. Further, the wireless communication unit 10114 receives a control signal related to the drive control of the capsule-type endoscope 10100 from the external control device 10200 via the antenna 10114A. The wireless communication unit 10114 supplies the control signal received from the external control device 10200 to the control unit 10117.

[0219] The power supply unit 10115 includes an antenna coil for receiving electric power, a power regeneration circuit for regenerating electric power from the electric current generated in the antenna coil, and a step-up circuit or the like. The power supply unit 10115 generates electric power using the principle of non-contact charging.

[0220] The power supply unit 10116 includes a secondary battery, and stores the electric power generated by the power supply unit 10115. In Figure 40 In the figure, an arrow mark for indicating the power receiving side of the power supply unit 10116 is omitted in order to avoid illustration complication. However, the electric power stored in the power supply unit 10116 is supplied to the light source unit 10111, the imaging unit 10112, the image processing unit 10113, the wireless communication unit 10114, and the control unit 10117, and can be used for driving these units.

[0221] The control unit 10117 includes a processor such as a CPU or the like, and appropriately controls the drive of the light source unit 10111, the imaging unit 10112, the image processing unit 10113, the wireless communication unit 10114, and the power supply unit 10115 in accordance with the control signal transmitted from the external control device 10200.

[0222] The external control device 10200 includes a processor such as a CPU or GPU, a microcomputer, or a control board in which a processor and a storage element (e.g., a memory) are combined in a hybrid manner, or the like. The external control device 10200 controls the operation of the capsule-type endoscope 10100 by transmitting a control signal to the control unit 10117 of the capsule-type endoscope 10100 via the antenna 10200A. In the capsule-type endoscope 10100, for example, the light illumination conditions of the observation target by the light source unit 10111 can be changed in accordance with the control signal from the external control device 10200. Further, the imaging conditions (e.g., the frame rate or the exposure value of the imaging unit 10112, or the like) can be changed in accordance with the control signal from the external control device 10200. Further, the processing content of the image processing unit 10113 or the conditions for transmitting the image signal from the wireless communication unit 10114 (e.g., the transmission interval or the number of images to be transmitted, or the like) can be changed in accordance with the control signal from the external control device 10200.

[0223] Further, the external control device 10200 performs various image processing on the image signal transmitted from the capsule endoscope 10100, and generates image data for displaying the captured in-vivo image on a display device. As the image processing, various signal processing such as development processing (demosaicing processing), image quality improvement processing (bandwidth increase processing, super resolution processing, noise reduction (NR) processing, and / or image stabilization processing), and / or enlargement processing (electronic zoom processing) can be performed, for example. The external control device 10200 controls the driving of the display device to cause the display device to display the captured in-vivo image on the basis of the generated image data. Alternatively, the external control device 10200 can also control a recording device (not shown) to record the generated image data, or control a printing device (not shown) and cause the printing device to output the generated image data by printing.

[0224] The above has explained an example of an in-vivo information acquisition system to which the technology according to the present disclosure can be applied. The technology according to the present disclosure can be applied to the imaging unit 10112 in the above-described configuration, for example. Thus, the detection accuracy is improved.

[0225] <Example of Application of Endoscopic Surgery System>

[0226] The technology according to the present disclosure (the present technology) is applicable to various products. For example, the technology according to the present disclosure can be applied to an endoscopic surgery system.

[0227] Figure 41 FIG. 1 is a diagram showing an example of a schematic configuration of an endoscopic surgery system to which the technology according to an embodiment of the present disclosure (the present technology) can be applied.

[0228] In Figure 41 In FIG. 1, a state in which a surgeon (doctor) 11131 performs surgery on a patient 11132 on a patient bed 11133 using an endoscopic surgery system 11000 is shown. As shown in the figure, the endoscopic surgery system 11000 includes an endoscope 11100, other surgical tools 11110 such as a pneumoperitoneum tube 11111 and an energy device 11112, a support arm device 11120 that supports the endoscope 11100, and a cart 11200 on which various devices for endoscopic surgery are installed.

[0229] The endoscope 11100 includes a lens barrel 11101, a region of a predetermined length from a distal end of the lens barrel 11101 being inserted into a body cavity of the patient 11132, and a camera head 11102 connected to a proximal end of the lens barrel 11101. In the example shown, the endoscope 11100 is shown as a rigid endoscope configured to have a rigid lens barrel 11101. However, the endoscope 11100 can also be configured as a flexible endoscope having a flexible lens barrel 11101.

[0230] An opening in which an objective lens is mounted is provided at the distal end of the lens barrel 11101. A light source device 11203 is connected to the endoscope 11100 so that light generated by the light source device 11203 is guided to the distal end of the lens barrel 11101 by a light guide extending within the lens barrel 11101, and the light is irradiated onto an observation target in the body cavity of the patient 11132 via the objective lens described above. Note that the endoscope 11100 can be a forward-viewing endoscope, or can be an oblique-viewing endoscope or a side-viewing endoscope.

[0231] An optical system and an image pickup element are provided within the camera head 11102 so that reflected light (observation light) from the observation target is converged onto the image pickup element by the optical system. The observation light is photoelectrically converted by the image pickup element, and an electric signal corresponding to the observation light, that is, an image signal corresponding to an observation image is generated. The image signal is sent to the CCU 11201 as raw data.

[0232] The CCU 11201 includes a central processing unit (CPU) or a graphics processing unit (GPU), and the like, and the CCU 11201 integrally controls the operation 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 processing such as development processing (demosaicing processing) and the like for displaying an image based on the image signal, for example, on the image signal.

[0233] Under the control of the CCU 11201, the display device 11202 displays an image based on the image signal (on which image processing has been performed by the CCU 11201) thereon.

[0234] For example, the light source device 11203 includes a light source such as a light emitting diode (LED) and supplies irradiation light at the time of imaging of the surgical region to the endoscope 11100.

[0235] The input device 11204 is an input interface of the endoscope surgery system 11000. The user can input various information or instructions to the endoscope surgery system 11000 through the input device 11204. For example, the user inputs an instruction for changing the imaging conditions (type of irradiation light, magnification, or focal distance, etc.) of the endoscope 11100 or the like.

[0236] The treatment tool control device 11205 controls the driving of the energy device 11112 for cauterization or incision of tissue or sealing of blood vessels or the like. The pneumoperitoneum device 11206 supplies gas into the body cavity of the patient 11132 through the pneumoperitoneum tube 11111 to inflate the body cavity, thereby securing the field of view of the endoscope 11100 and securing the working space of the surgeon. The recorder 11207 is a device capable of recording various information related to surgery. The printer 11208 is a device capable of printing various information related to surgery in various forms such as text, images, or charts.

[0237] Note that the light source device 11203 that supplies irradiation light at the time of imaging of the surgical region to the endoscope 11100 can include a white light source including, for example, an LED, a laser light source, or a combination of an LED and a laser light source. In the case where the white light source includes a combination of red, green, and blue (RGB) laser light sources, since the output intensity and the output timing of each color (each wavelength) can be controlled with high precision, the white balance of the captured image can be adjusted by the light source device 11203. Further, in this case, if the laser beams from each of the RGB laser light sources are irradiated to the observation object time-divisionally and the driving of the imaging element of the camera head 11102 is controlled in synchronization with the irradiation timing, images corresponding to the R, G, and B colors, respectively, can also be captured time-divisionally. According to this method, even if a color filter is not provided in the imaging element, a color image can be obtained.

[0238] Further, the light source device 11203 can be controlled so as to change the light intensity to be output per predetermined time. By controlling the driving of the imaging element of the camera head 11102 in synchronization with the timing of the change in light intensity and acquiring images time-divisionally, and then synthesizing the images, a high dynamic range image without underexposed blocked up shadow and overexposed highlight can be generated.

[0239] Further, the light source device 11203 can be configured to supply light of a predetermined wavelength band prepared for special light observation. In the special light observation, for example, by utilizing the wavelength dependency of light absorption in human tissue and irradiating light of a narrower band than the irradiation light (i.e., white light) at the time of ordinary observation, narrowband observation (narrowband imaging), i.e., imaging of a predetermined tissue such as a blood vessel in a mucosal surface layer at high contrast, is performed. Alternatively, in the special light observation, fluorescence observation in which an image is obtained by irradiation of excitation light to generate fluorescence can be performed. In the fluorescence observation, fluorescence from human tissue can be observed by irradiating the human tissue with excitation light (autofluorescence observation), or a fluorescence image can be obtained by locally injecting a reagent such as indocyanine green (ICG) into human tissue and irradiating the human tissue with excitation light corresponding to the fluorescence wavelength of the reagent. As described above, the light source device 11203 can be configured to supply such narrowband light and / or excitation light suitable for special light observation.

[0240] Figure 42 is a block diagram showing an example of the functional configuration of the camera head 11102 and the CCU 11201. Figure 41

[0241] The camera head 11102 includes a lens unit 11401, an imaging unit 11402, a driving 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 through a transmission cable 11400.

[0242] The lens unit 11401 is an optical system provided at the connection position with the barrel 11101. The observation light introduced from the distal end of the barrel 11101 is guided to the camera head 11102 and is incident to the lens unit 11401. The lens unit 11401 includes a combination of a plurality of lenses including a zoom lens and a focus lens.

[0243] ​The number of imaging elements included in the imaging unit 11402 can be one (single board type) or a plurality (multi board type). For example, in a case where the imaging unit 11402 is configured as a multi board type, image signals respectively corresponding to R, G, and B are generated by the respective imaging elements, and these image signals can be synthesized to obtain a color image. The imaging unit 11402 can also be configured to have a pair of imaging elements for respectively acquiring right eye image signals and left eye image signals ready for three-dimensional (3D) display. If 3D display is performed, the surgeon 11131 is able to more accurately grasp the depth of living tissue in a surgical site. Note that, in a case where the imaging unit 11402 is configured as a multi board type, a plurality of systems of the lens unit 11401 are provided corresponding to the respective imaging elements.

[0244] Further, the imaging unit 11402 is not necessarily provided on the camera head 11102. For example, the imaging unit 11402 can be provided inside the lens barrel 11101 and immediately behind the objective lens.

[0245] The drive unit 11403 includes an actuator, and under the control of the camera head control unit 11405, the drive unit 11403 moves the zoom lens and the focus lens of the lens unit 11401 along the optical axis by a predetermined distance. Thus, the magnification and the focus of the image captured by the imaging unit 11402 can be appropriately adjusted.

[0246] The communication unit 11404 includes a communication device for transmitting and receiving various information to and from the CCU 11201. The communication unit 11404 transmits an image signal obtained from the imaging unit 11402 to the CCU 11201 as raw data through the transmission cable 11400.

[0247] In addition, the communication unit 11404 receives a control signal for controlling the driving of the camera head 11102 from the CCU 11201 and supplies the control signal to the camera head control unit 11405. For example, the control signal includes information related to an imaging condition, such as information that specifies the frame rate of a captured image, information that specifies the exposure value at the time of imaging, and / or information that specifies the magnification and the focus of a captured image.

[0248] Note that the imaging condition such as the frame rate, the exposure value, the magnification, or the focus described above can be appropriately designated by a user, or can be automatically set by the control unit 11413 of the CCU 11201 based on an acquired image signal. In the latter case, the endoscope 11100 includes an auto exposure (AE) function, an auto focus (AF) function, and an auto white balance (AWB) function.

[0249] The camera control unit 11405 controls the driving of the camera head 11102 on the basis of a control signal from the CCU 11201 received through the communication unit 11404.

[0250] The communication unit 11411 includes 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 through the transmission cable 11400.

[0251] Further, the communication unit 11411 transmits a control signal for controlling the driving of the camera head 11102 to the camera head 11102. The above-described image signal and the above-described control signal can be transmitted through electric communication or optical communication, or the like.

[0252] The image processing unit 11412 performs various image processing on an image signal in the form of raw data transmitted from the camera head 11102.

[0253] The control unit 11413 performs various controls related to imaging of a surgical site or the like through the endoscope 11100 and display of a captured image obtained by imaging the surgical site or the like. For example, the control unit 11413 generates a control signal for controlling the driving of the camera head 11102.

[0254] Further, on the basis of an image signal that has been subjected to image processing by the image processing unit 11412, the control unit 11413 controls the display device 11202 to display a captured image of the surgical site or the like. Thus, the control unit 11413 can recognize various objects in the captured image using various image recognition techniques. For example, the control unit 11413 can recognize a surgical tool such as forceps, a specific living body site, bleeding, mist when the energy device 11112 is used, or the like by detecting the shape and color of the edge of an object included in the captured image. When the control unit 11413 controls the display device 11202 to display the captured image, the control unit 11413 can display various pieces of surgery assistance information in a superimposed manner on the image of the surgical site using the recognition result. In a case where the surgery assistance information is displayed in a superimposed manner and presented to the surgeon 11131, the burden on the surgeon 11131 can be reduced, and the surgeon 11131 can reliably perform surgery.

[0255] The transmission cable 11400 that connects the camera head 11102 and the CCU 11201 together is an electric signal cable prepared for electric signal communication, an optical fiber prepared for optical communication, or a composite cable prepared for electric communication and optical communication.

[0256] Here, in the example shown, although communication is performed in a wired manner using transmission cable 11400, communication between camera 11102 and CCU 11201 can also be performed wirelessly.

[0257] The above describes an example of an endoscopic surgical system to which the technology according to this disclosure can be applied. The technology according to this disclosure can be applied to the imaging unit 11402 in the above-described components. By applying the technology according to this disclosure to the imaging unit 11402, detection accuracy is improved.

[0258] It should be noted that although the endoscopic surgical system is used as an example here, the technology according to this disclosure can also be applied to, for example, microsurgical systems.

[0259] <Examples of applications of moving objects>

[0260] The technology disclosed herein is applicable to a variety of products. For example, the technology disclosed herein can be implemented as a device mounted on any type of mobile body, such as: automobiles, electric vehicles, hybrid vehicles, motorcycles, bicycles, personal mobile devices, airplanes, drones, ships, robots, construction machinery, or agricultural machinery (tractors).

[0261] Figure 43 This is a block diagram illustrating a schematic construction example of a vehicle control system that is an example of a mobile body control system capable of applying the technology according to embodiments of the present disclosure.

[0262] The vehicle control system 12000 includes multiple electronic control units interconnected via a communication network 12001. Figure 43 In the example shown, the vehicle control system 12000 includes: a drive system control unit 12010, a body system control unit 12020, an external information detection unit 12030, an internal information detection unit 12040, and an integrated control unit 12050. Furthermore, as part of the functional configuration of the integrated control unit 12050, a microcomputer 12051, an audio / image output unit 12052, and an in-vehicle network interface (I / F) 12053 are shown.

[0263] The drive system control unit 12010 controls the operation of equipment related to the vehicle's drive system according to various programs. For example, the drive system control unit 12010 serves as a control device for the following devices: drive force generating devices such as internal combustion engines or drive motors for generating drive force for the vehicle; drive force transmission mechanisms for transmitting drive force to the wheels; steering mechanisms for adjusting the vehicle's steering angle; and braking devices for generating braking force for the vehicle.

[0264] The body system control unit 12020 controls the operation of various devices mounted on the vehicle body in accordance with various programs. For example, the body system control unit 12020 functions as a control device for a keyless entry system, an intelligent key system, a power window device, or various lamps such as headlamps, tail lamps, brake lamps, turn signals, or fog lamps. In this case, radio waves transmitted from a mobile device that substitutes for a key or signals of various switches can be input to the body system control unit 12020. The body system control unit 12020 receives these input radio waves or signals and controls the door lock device, the power window device, or the lamps of the vehicle.

[0265] The outside -vehicle information detecting unit 12030 detects information outside the vehicle including the vehicle control system 12000. For example, the outside-vehicle information detecting unit 12030 is connected with an imaging section 12031. The outside-vehicle information detecting unit 12030 causes the imaging section 12031 to capture an image of the outside of the vehicle and receives the captured image. Based on the received image, the outside-vehicle information detecting unit 12030 can perform a detection process or a distance detection process on an object such as a pedestrian, a vehicle, an obstacle, a sign, or a letter on a road surface.

[0266] The imaging section 12031 is an optical sensor that receives light and outputs an electric signal corresponding to the amount of received light. The imaging section 12031 can output the electric signal as an image or can output the electric signal as measured distance information. Further, the light received by the imaging section 12031 can be visible light or can be non-visible light such as infrared rays.

[0267] The in-vehicle information detecting unit 12040 detects information inside the vehicle. The in-vehicle information detecting unit 12040 is connected with a driver state detecting section 12041 for detecting the state of a driver, for example. The driver state detecting section 12041 includes a camera for imaging the driver, for example. Based on detection information input from the driver state detecting section 12041, the in-vehicle information detecting unit 12040 can calculate the degree of fatigue or the degree of concentration of the driver or can determine whether the driver is dozing off.

[0268] Based on information about the outside or inside of the vehicle acquired by the outside-information detecting unit 12030 or the in-vehicle information detecting unit 12040, the microcomputer 12051 is able to calculate a control target value of a driving force generating device, a steering mechanism, or a braking device, and is able to output a control command to the drive system control unit 12010. For example, the microcomputer 12051 is able to perform cooperative control for realizing an advanced driver assistance system (ADAS: advanced driver assistance system) function including collision avoidance or impact mitigation of the vehicle, follow-up travel based on a following distance, vehicle speed maintenance travel, vehicle collision warning, or lane deviation warning of the vehicle, and the like.

[0269] Further, the microcomputer 12051 is able to control a driving force generating device, a steering mechanism, or a braking device, and the like, based on information about the outside or inside of the vehicle acquired by the outside-information detecting unit 12030 or the in-vehicle information detecting unit 12040, thereby performing cooperative control for realizing autonomous driving of the vehicle independently of the operation of the driver, or the like.

[0270] Further, based on information about the outside of the vehicle acquired by the outside-information detecting unit 12030, the microcomputer 12051 is able to output a control command to the body system control unit 12020. For example, the microcomputer 12051 is able to control a headlamp and switch a high beam to a low beam, for example, in accordance with the position of a preceding vehicle or an oncoming vehicle detected by the outside-information detecting unit 12030, thereby performing cooperative control for preventing glare.

[0271] The sound / image output section 12052 transmits an output signal of at least one of a sound and an image to an output device that is able to visually or aurally notify a passenger on the vehicle or outside of the vehicle of information. In Figure 43 Examples of the output device are shown as an audio speaker 12061, a display section 12062, and an instrument panel 12063. The display section 12062 can include at least one of an on-board display and a head-up display, for example.

[0272] Figure 44 is a view showing an example of a mounting position of the imaging section 12031.

[0273] In Figure 44 , the imaging section 12031 includes imaging sections 12101, 12102, 12103, 12104, and 12105.

[0274] The imaging sections 12101, 12102, 12103, 12104, and 12105 are provided, for example, at positions of a front nose, a rearview mirror, a rear bumper, and a rear door of the vehicle 12100 and a position of an upper portion of a windshield inside the vehicle. The imaging section 12101 provided at the front nose and the imaging section 12105 provided at the upper portion of the windshield inside the vehicle mainly acquire images of a front of the vehicle 12100. The imaging sections 12102 and 12103 provided at the rearview mirror mainly acquire images of sides of the vehicle 12100. The imaging section 12104 provided at the rear bumper or the rear door mainly acquires an image of a rear of the vehicle 12100. The imaging section 12105 provided at the upper portion of the windshield inside the vehicle is mainly used for detecting a preceding vehicle, a pedestrian, an obstacle, a traffic signal, a traffic sign, or a lane.

[0275] Incidentally, Figure 44 Examples of imaging ranges of the imaging sections 12101 to 12104 are shown. The imaging range 12111 indicates an imaging range of the imaging section 12101 provided at the front nose. The imaging ranges 12112 and 12113 indicate imaging ranges of the imaging sections 12102 and 12103 provided at the rearview mirror, respectively. The imaging range 12114 indicates an imaging range of the imaging section 12104 provided at the rear bumper or the rear door. For example, a bird's-eye view image of the vehicle 12100 viewed from above is obtained by superimposing image data imaged by the imaging sections 12101 to 12104.

[0276] At least one of the imaging sections 12101 to 12104 can have a function of acquiring distance information. For example, at least one of the imaging sections 12101 to 12104 can be a stereo camera composed of a plurality of imaging elements or can be an imaging element having pixels for phase difference detection.

[0277] For example, the microcomputer 12051 can determine distances to each three-dimensional object within the imaging ranges 12111 to 12114 and changes in the distances over time (relative speeds with respect to the vehicle 12100) on the basis of distance information obtained from the imaging sections 12101 to 12104, and thereby extract, as a preceding vehicle, a three-dimensional object that is closest to the vehicle 12100 on a travel road and travels at a predetermined speed (for example, greater than or equal to 0 km / h) in almost the same direction as the vehicle 12100. Further, the microcomputer 12051 can set a following distance to be maintained in front of the preceding vehicle in advance, and can perform automatic brake control (including follow-up stop control) or automatic acceleration control (including follow-up start control) or the like. Thus, cooperative control for realizing automatic driving or the like in which the vehicle autonomously travels without depending on an operation of a driver can be performed.

[0278] For example, based on distance information obtained from the imaging sections 12101 to 12104, the microcomputer 12051 can classify three-dimensional object data on a three-dimensional object into three-dimensional object data of a two-wheeled vehicle, a standard vehicle, a large vehicle, a pedestrian, a utility pole, and other three-dimensional objects, extract the classified three-dimensional object data, and use the extracted three-dimensional object data to automatically avoid obstacles. For example, the microcomputer 12051 identifies obstacles around the vehicle 12100 as obstacles that the driver of the vehicle 12100 can visually recognize and obstacles that the driver of the vehicle 12100 is difficult to visually recognize. Then, the microcomputer 12051 determines a collision risk that indicates a risk of collision with each obstacle. In a case where the collision risk is equal to or higher than a set value and thus there is a possibility of collision, the microcomputer 12051 outputs a warning to the driver through the audio speaker 12061 or the display section 12062 and performs forced deceleration or evasive steering through the drive system control unit 12010. Thus, the microcomputer 12051 can assist driving to avoid collision.

[0279] At least one of the imaging sections 12101 to 12104 can be an infrared camera for detecting infrared rays. For example, the microcomputer 12051 can recognize a pedestrian by determining whether a pedestrian is present in an image captured by the imaging sections 12101 to 12104. Such pedestrian recognition is performed, for example, by extracting feature points in an image captured by the imaging sections 12101 to 12104 as an infrared camera and determining whether an object is a pedestrian by performing pattern matching processing on a series of feature points that represent the outline of the object. When the microcomputer 12051 determines that a pedestrian is present in an image captured by the imaging sections 12101 to 12104 and recognizes the pedestrian, the sound / image output section 12052 controls the display section 12062 so that a rectangular outline line for emphasis is superimposed and displayed on the recognized pedestrian. The sound / image output section 12052 can also control the display section 12062 so that an icon or the like indicating a pedestrian is displayed at a desired position.

[0280] Although the disclosure has been described with reference to the first and second embodiments, modified examples 1 to 7, applicable examples, and application examples, the disclosure is not limited to the above-described embodiments and the like. Various modifications can be made. For example, as modified example 3 explained as a combined example of the first embodiment and modified example 2, the first and second embodiments and modified examples 1 to 7 can be combined with each other.

[0281] Further, for example, although the imaging element 10A in the above-described first embodiment has a configuration in which the photoelectric conversion section 20 that detects green light and the inorganic photoelectric conversion sections 32B and 32R that respectively detect blue light and red light are stacked, the content of the present disclosure is not limited to this structure. In other words, the photoelectric conversion section 20 can detect red light or blue light, or the inorganic photoelectric conversion sections can respectively detect green light.

[0282] Further, the number of photoelectric conversion sections (for example, the photoelectric conversion section 20) provided on the light-receiving surface (the first surface 30S1) side of the semiconductor substrate 30, the number of inorganic photoelectric conversion sections (for example, the inorganic photoelectric conversion sections 32B and 32R) embedded and formed in the semiconductor substrate 30, or the ratio between the photoelectric conversion sections and the inorganic photoelectric conversion sections is not limited. For example, a plurality of photoelectric conversion sections can be provided on the light-receiving surface (the first surface 30S1) side of the semiconductor substrate 30 to obtain color signals of a plurality of colors.

[0283] Further, in the above-described embodiments and the like, an example in which the plurality of electrodes that constitute the lower electrode 21 include the two electrodes of the readout electrode 21A and the accumulation electrode 21B has been described. However, three or four or more electrodes including a transfer electrode or a discharge electrode, or the like can also be provided.

[0284] Further, in the above-described first embodiment, although an example in which the charge accumulation layer 23, the photoelectric conversion layer 24, and the upper electrode 25 are formed as a continuous layer common to the plurality of imaging elements 10A has been described, the charge accumulation layer 23, the photoelectric conversion layer 24, and the upper electrode 25 can also be formed individually for each pixel P. However, in this case, the dark current characteristics can be degraded due to the influence of process damage on the charge accumulation layer 23 and the photoelectric conversion layer 24. Further, as in the above-described first embodiment, in a case where the continuous layer common to the plurality of imaging elements 10A is formed so as to extend in the effective pixel region 110A, the pixels are connected to each other through the photoelectric conversion layer. Thus, color mixing due to charge mixing between the pixels can occur. This case is suppressed by providing the shield electrode 21C as described above.

[0285] Note that the effects described herein are merely examples and are not limiting. Additionally, other effects can be present.

[0286] Note that the present disclosure can have the following configuration. The following configuration according to the present technology suppresses entry of hydrogen into the photoelectric conversion layer and the charge accumulation layer via the interlayer insulating layer, and thus can improve reliability. (1)

[0288] An imaging element including:

[0289] A semiconductor substrate having an effective pixel region in which a plurality of pixels are arranged and a peripheral region arranged around the effective pixel region;

[0290] a photoelectric conversion section including a first electrode, a second electrode, and a charge accumulation layer and a photoelectric conversion layer, the first electrode being provided on a light-receiving surface side of the semiconductor substrate and including a plurality of electrodes, the second electrode being provided so as to face the first electrode, the charge accumulation layer and the photoelectric conversion layer being sequentially stacked and provided between the first electrode and the second electrode and extending in the effective pixel region;

[0291] a first hydrogen barrier layer covering a top and side surfaces of the photoelectric conversion layer and a side surface of the charge accumulation layer;

[0292] an interlayer insulating layer provided between the semiconductor substrate and the photoelectric conversion section; and

[0293] a separation groove separating the interlayer insulating layer in at least a portion of a region between the effective pixel region and the peripheral region, a side surface and a bottom surface of the separation groove being covered by the first hydrogen barrier layer. (2)

[0295] The imaging element according to (1), wherein the separation groove is continuously provided around the effective pixel region. (3)

[0297] The imaging element according to (2), wherein one or a plurality of the separation grooves are provided. (4)

[0299] The imaging element according to any one of (1) to (3), further comprising one or a plurality of transfer electrodes for external output in the peripheral region, wherein

[0300] the separation groove is provided at a position closer to the effective pixel region than the one or a plurality of transfer electrodes. (5)

[0302] The imaging element according to (4), wherein

[0303] the semiconductor substrate further includes a logic substrate on a surface side opposite to the light-receiving surface, and

[0304] the transfer electrode is provided on the logic substrate, and the transfer electrode has an opening having a through-hole extending through the interlayer insulating layer and the semiconductor substrate. (6)

[0306] The imaging element according to (4) or (5), wherein the separation groove is continuously provided around the one or more transfer electrodes in a plan view. (7)

[0308] The imaging element according to (6), wherein the separation groove is provided for each of the transfer electrodes. (8)

[0310] The imaging element according to any one of (5) to (7), wherein a depth of the separation groove is greater than or equal to a thickness of the interlayer insulating layer and less than or equal to a depth of the opening. (9)

[0312] The imaging element according to any one of (5) to (8), wherein a depth of the separation groove is greater than a depth of the opening. (10)

[0314] The imaging element according to any one of (1) to (9), further comprising a lens on a light-receiving surface side of the photoelectric conversion section, wherein

[0315] The lens is formed using a material that is the same as a material of the first hydrogen barrier layer. (11)

[0317] The imaging element according to any one of (1) to (10), wherein the photoelectric conversion layer is formed using an organic material. (12)

[0319] The imaging element according to any one of (1) to (11), wherein the photoelectric conversion layer is formed using an inorganic material. (13)

[0321] The imaging element according to (11), wherein the organic material includes a rhodamine-based dye, a merocyanine-based dye, a quinacridone derivative, a subphthalocyanine-based dye, a coumalin dye, 3-8-hydroxyquinoline aluminum (Alq3), and a phthalocyanine-based dye or a derivative thereof. (14)

[0323] The imaging element according to (12), wherein the inorganic material includes crystalline silicon, amorphous silicon, microcrystalline silicon, crystalline selenium, amorphous selenium, a chalcopyrite compound, and a compound semiconductor. (15)

[0325] The imaging element according to (12), wherein the inorganic material is used in a quantum dot shape. (16)

[0327] The imaging element according to any one of (1) to (15), further comprising a second hydrogen barrier layer below the charge accumulation layer. (17)

[0329] The imaging element according to (16), wherein the second hydrogen barrier layer is provided between the semiconductor substrate and the charge accumulation layer. (18)

[0331] The imaging element according to (16) or (17), wherein

[0332] The photoelectric conversion section further includes an insulating layer between the first electrode and the charge accumulation layer, and

[0333] The insulating layer is formed as the second hydrogen barrier layer. (19)

[0335] The imaging element according to any one of (1) to (18), wherein the first hydrogen barrier layer is formed to include a metal oxide having light transmittance and an oxide semiconductor having light transmittance. (20)

[0337] An imaging device including:

[0338] An imaging element, wherein

[0339] The imaging element includes:

[0340] A semiconductor substrate having an effective pixel region in which a plurality of pixels are arranged and a peripheral region arranged around the effective pixel region;

[0341] A photoelectric conversion section including a first electrode provided on a light-receiving surface side of the semiconductor substrate and including a plurality of electrodes, a second electrode provided so as to face the first electrode, and a charge accumulation layer and a photoelectric conversion layer stacked in this order between the first electrode and the second electrode and extending in the effective pixel region;

[0342] A first hydrogen barrier layer covering a top and side surfaces of the photoelectric conversion layer and a side surface of the charge accumulation layer;

[0343] An interlayer insulating layer provided between the semiconductor substrate and the photoelectric conversion section; and

[0344] A separation groove separating the interlayer insulating layer in at least a part of a region between the effective pixel region and the peripheral region, a side surface and a bottom surface of the separation groove being covered by the first hydrogen barrier layer.

[0345] This application claims priority to Japanese Patent Application No. 2019-025595 filed on February 15, 2019 with the Japan Patent Office, the entire contents of which are incorporated herein by reference.

[0346] Those skilled in the art will understand that various modifications, combinations, sub-combinations, and alterations can occur depending on design requirements and other factors insofar as they are within the scope of the appended claims or the equivalents thereof.

Claims

1. An imaging element comprising: a semiconductor substrate having an effective pixel region in which a plurality of pixels are arranged and a peripheral region arranged around the effective pixel region; a photoelectric conversion section including a first electrode, a second electrode, and a charge accumulation layer and a photoelectric conversion layer, the first electrode being provided on a light-receiving surface side of the semiconductor substrate and including a plurality of electrodes, the second electrode being provided so as to oppose the first electrode, the charge accumulation layer and the photoelectric conversion layer being sequentially stacked and provided between the first electrode and the second electrode and extending in the effective pixel region; a first hydrogen barrier layer covering an upper side and a side surface of the photoelectric conversion layer and a side surface of the charge accumulation layer; an interlayer insulating layer provided between the semiconductor substrate and the photoelectric conversion section; and a separation groove separating the interlayer insulating layer in at least a portion between the effective pixel region and the peripheral region, a side surface and a bottom surface of the separation groove being covered by the first hydrogen barrier layer, wherein the first hydrogen barrier layer is formed to include a metal oxide having light transmittance and an oxide semiconductor having light transmittance. The separation groove is continuously provided around the effective pixel region.

2. The image pickup element according to claim 1, wherein One or more of the separation grooves are provided.

3. The image pickup element according to claim 2, wherein 4. The imaging element according to claim 1, further comprising one or more transfer electrodes for external output in the peripheral region, wherein the separation groove is provided closer to the effective pixel region than the one or more transfer electrodes.

5. The imaging element according to claim 4, wherein the semiconductor substrate further includes a logic substrate on a surface side opposite to the light-receiving surface, and the transfer electrode is provided on the logic substrate, and the transfer electrode has an opening therethrough the interlayer insulating layer and the semiconductor substrate. The separation groove is continuously provided around the one or more transfer electrodes in a plan view.

6. The image pickup element according to claim 4, wherein The separation groove is provided for each of the transfer electrodes.

7. The image pickup element according to claim 6, wherein A depth of the separation groove is greater than or equal to a thickness of the interlayer insulating layer and less than or equal to a depth of the opening. 8.The imaging device according to claim 5, wherein The depth of the separation groove is greater than the depth of the opening.

9. The image pickup element according to claim 5, wherein 10. The imaging element according to claim 1, further comprising a lens on a light-receiving surface side of the photoelectric conversion section, wherein the lens is formed using a same material as a material of the first hydrogen barrier layer. The photoelectric conversion layer is formed using an organic material.

11. The image pickup element according to claim 1, wherein The photoelectric conversion layer is formed using an inorganic material.

12. The imaging device according to claim 1, wherein The organic material includes a rhodamine-based dye, a merocyanine-based dye, a quinacridone derivative, a subphthalocyanine-based dye, a coumalin dye, 3-8-hydroxyquinoline aluminum, and a phthalocyanine-based dye or a derivative thereof.

13. The image pickup element according to claim 11, wherein The inorganic material includes crystalline silicon, amorphous silicon, microcrystalline silicon, crystalline selenium, amorphous selenium, a chalcopyrite compound, and a compound semiconductor.

14. The image pickup element according to claim 12, wherein The inorganic material is used in a quantum dot shape.

15. The image pickup element according to claim 12, wherein 16. The imaging element according to claim 1, further comprising a second hydrogen barrier layer below the charge accumulation layer. The second hydrogen barrier layer is provided between the semiconductor substrate and the charge accumulation layer.

17. The image pickup element according to claim 16, wherein ​ 18. The image pickup element according to claim 16, wherein the photoelectric conversion section further includes an insulating layer between the first electrode and the charge accumulation layer, and the insulating layer is formed as the second hydrogen barrier layer.

19. An image pickup apparatus including the image pickup element according to any one of claims 1-18.

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