Image forming apparatus

Abstract

[Problem] To improve optical characteristics and suppress dark current. [Solution] In the present invention, an imaging device is provided with: a plurality of pixels; and a pixel boundary region disposed between two pixels adjacent to each other. Each pixel includes: a photoelectric conversion layer containing a compound semiconductor material; a first electrode provided on the light incident surface side of the photoelectric conversion layer and containing a compound semiconductor material; and a second electrode disposed on an opposite surface side with respect to the light incident surface side of the photoelectric conversion layer and transferring the charge photoelectrically converted in the photoelectric conversion layer. Each of the pixel boundary regions includes: a high-concentration impurity region extending from the light incident surface side to the opposite surface side; a third electrode electrically insulated from the high-concentration impurity region and provided along the high-concentration impurity region; and the fourth electrode is electrically conducted with the first electrode.

Description

Technical Field

[0001] The present disclosure relates to an imaging device. Background Art

[0002] In an infrared sensor having sensitivity in an infrared region, for example, a photoelectric conversion layer containing a compound semiconductor material such as indium gallium arsenide (InGaAs) or indium phosphide (InP) is used.

[0003] In this infrared sensor, no impurity concentration gradient is applied to the photoelectric conversion layer, so it is necessary to provide electrodes not only on the pixel circuit side of the photoelectric conversion layer but also on the light incident surface side. In addition, it is necessary to suppress dark current caused by crystal defects in the photoelectric conversion layer. Therefore, a technology has been proposed to configure a transparent electrode on the light incident surface side of the photoelectric conversion layer and to provide an impurity diffusion region in the boundary region between two adjacent pixels to suppress the generation of dark current (for example, refer to Patent Document 1).

[0004] Reference List

[0005] Patent Literature

[0006] Patent Document 1: WO 2018 / 212175 A1 Summary of the invention

[0007] Problems to be solved by the present invention

[0008] However, when the transparent electrode is arranged on the light incident surface side of the photoelectric conversion layer, the optical properties of infrared light may be degraded to a certain extent. In addition, when the impurity diffusion region is arranged in the boundary region between two adjacent pixels, the effect of suppressing dark current cannot be fully obtained unless the voltage applied to the impurity diffusion region is optimized.

[0009] Therefore, the present disclosure provides an imaging device having excellent optical characteristics and capable of suppressing dark current.

[0010] Solution to the problem

[0011] In order to solve the above problems, according to the present disclosure, an imaging device is provided, comprising:

[0012] A plurality of pixels; and

[0013] A pixel boundary region is set between two adjacent pixels, where

[0014] Each of the plurality of pixels includes:

[0015] A photoelectric conversion layer comprising a compound semiconductor material;

[0016] a first electrode provided on the light incident surface side of the photoelectric conversion layer and containing a compound semiconductor material; and

[0017] a second electrode which is provided on the opposite surface side with respect to the light incident surface side of the photoelectric conversion layer and transfers the charges photoelectrically converted in the photoelectric conversion layer, and

[0018] The pixel boundary area includes:

[0019] A high-concentration impurity region extending from the light incident surface side to the opposite surface side;

[0020] A third electrode electrically insulated from the high-concentration impurity region and disposed along the high-concentration impurity region; and

[0021] A fourth electrode is electrically connected to the first electrode.

[0022] The high-concentration impurity region may have a higher impurity content per unit volume than the photoelectric conversion layer.

[0023] The third electrode may be set to a voltage that induces specific charges in the high-concentration impurity region.

[0024] The specific charges may be charges having a polarity different from the polarity of charges photoelectrically converted in the photoelectric conversion layer and transferred to the second electrode.

[0025] The first electrode may be a semiconductor layer containing a compound semiconductor material different from that of the photoelectric conversion layer.

[0026] The fourth electrode may be provided from the opposite surface side with respect to the light incident surface side of the photoelectric conversion layer to a height reacting with the first electrode.

[0027] The third electrode may be provided between the fourth electrode and the high-concentration impurity region.

[0028] The third electrode may be provided from the opposite surface side to the light incident surface side of the photoelectric conversion layer to a height that does not reach the first electrode.

[0029] A high-concentration impurity region may be provided to surround a pixel, and

[0030] The third electrode may be provided to surround the high-concentration impurity region for each of the plurality of pixels.

[0031] The plurality of pixels may be arranged in a first direction and a second direction,

[0032] Two third electrodes included in two pixels disposed adjacent to each other in the first direction may be connected at a pixel boundary region between the two pixels disposed adjacent to each other in the first direction, and

[0033] Two third electrodes included in two pixels disposed adjacent to each other in the second direction may be connected at a pixel boundary region between the two pixels disposed adjacent to each other in the second direction.

[0034] The fourth electrode may be disposed in a pixel boundary region between two pixels disposed adjacent to each other in a diagonal direction.

[0035] The imaging device may further include a wiring layer provided on an opposite surface side with respect to the light incident surface side of the photoelectric conversion layer, and

[0036] For each of the plurality of pixels, the wiring layer may include:

[0037] A first wiring region electrically connected to the second electrode; and

[0038] A second wiring region electrically connected to the fourth electrode.

[0039] For each of the plurality of pixels, the wiring layer may include a third wiring region electrically connected to the third electrode.

[0040] An end portion of the high-concentration impurity region on the light incident surface side may be connected to the first electrode, and

[0041] An end portion of the high-concentration impurity region on the opposite surface side with respect to the light incident surface side may be connected to the fourth electrode.

[0042] A high-concentration impurity region may be provided to surround a pixel, and

[0043] The fourth electrode may be provided to surround the high-concentration impurity region for each of the plurality of pixels.

[0044] The third electrode may be disposed in a lattice pattern in a plurality of pixel boundary regions between the plurality of pixels.

[0045] The imaging device may further include a wiring layer provided on an opposite surface side with respect to the light incident surface side of the photoelectric conversion layer, and

[0046] For each of the plurality of pixels, the wiring layer may include a first wiring region electrically connected to the second electrode.

[0047] For each of the plurality of pixels, the wiring layer may include a second wiring region electrically connected to the fourth electrode.

[0048] The plurality of third electrodes disposed in the plurality of pixel boundary regions between the plurality of pixels may be electrically connected to each other, and

[0049] The plurality of fourth electrodes disposed in the plurality of pixel boundary regions may be electrically connected to each other. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] Figure 1 is a block diagram showing the outline of an imaging device according to the present disclosure.

[0051] Figure 2 Schematic diagram showing a laminated structure of an imaging device according to the present disclosure.

[0052] Figure 3 is a plan view of a pixel region in the first embodiment of the present disclosure.

[0053] Figure 4A is along Figure 3 A cross-sectional view taken along line AA of the pixel area in FIG.

[0054] Figure 4B is along Figure 3 A cross-sectional view taken along line BB of the pixel region in FIG.

[0055] Figure 5 is a schematic diagram illustrating a state in which charges move in a pixel according to the first embodiment of the present disclosure.

[0056] Fig. 6A is a cross-sectional view of an imaging device according to a first comparative example.

[0057] Figure 6B is a cross-sectional view of an imaging device according to a second comparative example.

[0058] Fig. 7A 2 is a view showing a step of forming a laminate.

[0059] Figure 7B is a diagram illustrating a step of forming a groove in a laminate.

[0060] Figure 7C is a diagram illustrating a step of forming an impurity diffusion region in a laminate.

[0061] Fig.7D is shown along the Figure 3 A diagram of a step of forming a pinned electrode in a laminate in a cross-sectional view taken along line AA of a pixel area in FIG.

[0062] Fig. 7E is shown along the Figure 3 FIG. 1 is a diagram of a step of forming a pinned electrode in a laminate in a cross-sectional view taken along line BB of a pixel area in FIG.

[0063] Figure 7F is shown along the Figure 3 A diagram of the step of digging the groove area of ​​the laminate in a cross-sectional view taken along line AA of the pixel area in FIG.

[0064] Figure 7G is shown along the Figure 3A diagram of a step of covering the pinning electrode and the transfer electrode of the laminate with an insulating material in a cross-sectional view taken along line AA of a pixel area in FIG.

[0065] Figure 7H is shown along the Figure 3 A diagram of a step of covering the pinning electrode and the transfer electrode of the laminate with an insulating material in a cross-sectional view taken along line BB of a pixel region in FIG.

[0066] Fig.7I It shows that along Figure 3 A diagram of a step of forming a groove for a through electrode of a laminate in a cross-sectional view taken along line AA of a pixel region in FIG.

[0067] Figure 7J is shown along the Figure 3 A diagram of a step of forming a through electrode of a laminate in a cross-sectional view taken along line AA of a pixel region in FIG.

[0068] Fig. 8A : is a cross-sectional view showing an example of wiring connection between a transfer electrode, a penetration electrode, and a pinning electrode of a pixel and a pixel circuit according to the first embodiment of the present disclosure.

[0069] Figure 8B : is a cross-sectional view showing an example of wiring connection between a transfer electrode and a through-electrode of a pixel and a pixel circuit according to the first embodiment of the present disclosure.

[0070] Fig. 9 1 is a diagram showing a cross-sectional structure of an imaging device in a first modification example of the first embodiment of the present invention.

[0071] Fig.10 It is a plan view of a pixel region in a second modified example of the first embodiment of the present invention.

[0072] Fig.11 It is along Fig.10 A cross-sectional view taken along line BB of the pixel region in FIG.

[0073] Fig.12 It is a plan view of a pixel region in a third modified example of the first embodiment of the present invention.

[0074] Fig.13 It is a plan view of a pixel region in a fourth modified example of the first embodiment of the present invention.

[0075] Fig.14 1 is a cross-sectional structure of an imaging device in a fifth modification example of the first embodiment of the present invention.

[0076] Fig.15 is a plan view of a pixel region in the second embodiment of the present disclosure.

[0077] Fig.16 It is along Fig.15 A cross-sectional view of the pixel area taken along line CC.

[0078] Fig.17A is a diagram showing a step of forming a pinning electrode and a transfer electrode in a laminate.

[0079] Fig. 17B is a diagram showing a step of forming an insulating layer in a laminate.

[0080] Fig. 17C is a diagram showing a step of forming a groove portion in an insulating layer of a laminate.

[0081] Fig.17D is a diagram showing a step of forming a groove in an insulating layer of a laminate.

[0082] Fig.17E is a diagram showing a step of forming an electrode in an insulating layer of a laminate.

[0083] Fig.18A : is a cross-sectional view showing an example of wiring connection between a transfer electrode and an electrode of a pixel and a pixel circuit according to a second embodiment of the present disclosure.

[0084] Fig.18B is a cross-sectional view illustrating an example of wiring connection between an electrode of a pixel and a pixel circuit according to a second embodiment of the present invention.

[0085] Fig.19 is a cross-sectional view of an imaging device in a first modified example of the second embodiment of the present invention.

[0086] Fig. 20 is a cross-sectional view of an imaging device in a second modification example of the second embodiment of the present disclosure.

[0087] Fig.21 is a block diagram showing an embodiment of a schematic configuration of a vehicle control system.

[0088] Fig. 22 It is an explanatory diagram showing an embodiment of the installation positions of the vehicle exterior information detection unit and the imaging unit. DETAILED DESCRIPTION

[0089] Hereinafter, embodiments of the imaging device will be described with reference to the accompanying drawings. Although the main components of the imaging device will be mainly described below, the imaging device may have components and functions not shown or described. The following description does not exclude components and functions not shown or described.

[0090] (Overview of Imaging Device)

[0091] Figure 1 1 is a block diagram showing an overview of an imaging device 1 according to the present disclosure. For example, the imaging device 1 according to the present disclosure images light in the infrared band. The imaging device 1 according to the present disclosure includes a pixel area 2 and a circuit unit 3. The circuit unit 3 includes a row scanning unit 31, a horizontal selection unit 32, a column scanning unit 33, and a system control unit 34.

[0092] The pixel area 2 has a configuration in which a plurality of pixels 20 are arranged two-dimensionally in a matrix form. Here, the column direction is a direction in which a plurality of pixel drive lines 35 are arranged, and is a direction in which each signal line 36 extends. The row direction is a direction in which a plurality of signal lines 36 are arranged, and is a direction in which each pixel drive line 35 extends. In this specification, a row of pixels 20 arranged along the row direction is referred to as a pixel row, and a column of pixels 20 arranged along the column direction is referred to as a pixel column. In the pixel area 2, a pixel drive line 35 is provided for each pixel row. One end of the pixel drive line 35 is connected to an output terminal corresponding to each row of the row scanning unit 31. In addition, a signal line 36 is provided for each pixel column. Each signal line 36 transmits a pixel signal output from each pixel 20 in the corresponding pixel column.

[0093] Although not shown, the row scanning unit 31 and the column scanning unit 33 include a shift register, an address decoder, etc. In addition, the horizontal selection unit 32 includes an amplifier, a horizontal selection switch, etc. As described above, a plurality of pixel drive lines 35 are connected to the row scanning unit 31. The row scanning unit 31 sequentially drives the plurality of pixel drive lines 35 to sequentially select corresponding pixel rows in the pixel area 2. Each pixel 20 in the selected pixel row supplies a pixel signal to the horizontal selection unit 32 via a corresponding signal line 36. The column scanning unit 33 controls the selection of the signal line by the horizontal selection unit 32. Under the control of the column scanning unit 33, the horizontal selection unit 32 sequentially selects the pixel signals on the plurality of signal lines and supplies the selected pixel signals to a signal processing unit (not shown) or the like via a signal line 37 extending in the horizontal direction.

[0094] The system control unit 34 receives a clock supplied from the outside and synchronously controls the row scanning unit 31 , the horizontal selection unit 32 , the column scanning unit 33 , etc. Furthermore, the system control unit 34 receives data for indicating an operation mode and outputs data such as internal information of the imaging device 1 .

[0095] Figure 2 is a schematic diagram showing a laminated structure of the imaging device 1 according to the present disclosure. For example, the imaging device 1 according to the present disclosure may be configured with a laminated structure of semiconductor chips. Figure 2The imaging device 1 in the embodiment is configured by laminating a pixel chip 11 in which a pixel region 2 is arranged and a circuit chip 12 in which a pixel circuit, a circuit unit 3, etc. are arranged. These chips are connected by Cu-Cu bonding or the like and transmit various signals. Note that in addition to Cu-Cu bonding, the pixel chip 11 and the circuit chip 12 may be connected by vias, bumps, etc. However, the imaging device 1 is not limited to having Figure 2 For example, the imaging device 1 may have a flat chip structure in which the pixel region 2 and the circuit unit 3 are arranged on the same chip.

[0096] (First embodiment of the present invention)

[0097] Figure 3 , Figure 4A and Figure 4B 1 are a plan view and a cross-sectional view showing the structure of the pixel region 2 according to the first embodiment of the present disclosure. Figure 3 is a plan view of the pixel region 2. Figure 3 As shown, the pixel region 2 includes a plurality of pixels 20 arranged two-dimensionally. A pixel boundary region 21 is provided between two pixels 20 arranged adjacent to each other in the first direction X and between two pixels 20 arranged adjacent to each other in the second direction Y.

[0098] like Figure 3 As shown, in the pixel boundary region 21, a high-concentration impurity region 211, a pinning electrode 212 (third electrode) and a through electrode 213 (fourth electrode) are provided. The high-concentration impurity region 211 is provided for each pixel 20 and is arranged to surround the pixel 20. The details of the high-concentration impurity region 211 will be described later. The pinning electrode 212 is provided for each pixel 20, and is arranged to surround the pixel 20 and the high-concentration impurity region 211. The pinning electrode 212 is connected to the pinning electrode 212 adjacent thereto in the first direction X and the second direction Y. The through electrode 213 is provided between every two pixels in the pixels 20 adjacent to each other in the diagonal direction.

[0099] Figure 4A It is along Figure 3 A cross-sectional view taken along line AA in FIG. Figure 4B It is along Figure 3 A cross-sectional view taken along line BB in FIG. Figure 4A 2 shows a cross-sectional structure of two pixels 20 adjacent to each other in the diagonal direction. Figure 4B FIG. 2 shows a cross-sectional structure of two pixels 20 adjacent to each other in the first direction X. Figure 4A and Figure 4B , the light incident surface is shown on the lower side.

[0100] like Figure 4AAs shown, the pixel 20 is provided with a contact layer 201 (first electrode), a photoelectric conversion layer 202, an impurity diffusion region 203, a contact layer 204 and a transfer electrode 205 (second electrode) in order from the light incident surface side along the stacking direction. In the pixel boundary region 21, a high concentration impurity region 211, a pinning electrode 212 (third electrode) and a through electrode 213 (fourth electrode) are provided respectively. The contact layer 201 and the contact layer 204 are provided opposite to each other.

[0101] The contact layers 201 and 204 are semiconductor layers containing a compound semiconductor material (e.g., InP). The impurity diffusion region 203 is a region where impurities are injected into a portion of the contact layer 204 and diffused. Charges generated by photoelectric conversion in the photoelectric conversion layer 202 are transferred to the transfer electrode 205 by a bias voltage applied between the transfer electrode 205 connected to the contact layer 204 and the impurity diffusion region 203 and the contact layer 201.

[0102] The photoelectric conversion layer 202 is a semiconductor layer containing, for example, a compound semiconductor material (for example, InGaAs) different from the compound semiconductor material of the contact layers 201 and 204. The photoelectric conversion layer 202 is provided between the contact layers 201 and 204. The photoelectric conversion layer 202 is a light absorption layer. The photoelectric conversion layer 202 absorbs light transmitted through the contact layer 201 and generates signal charges.

[0103] The transfer electrode 205 is an electrode to which a voltage is applied for reading the charge accumulated as a signal charge in the photoelectric conversion layer 202. The transfer electrode 205 is provided for each pixel 20 and is electrically connected to a pixel circuit (not shown). Between the transfer electrode 205 and the photoelectric conversion layer 202, two or more semiconductor layers having a capping energy greater than that of the photoelectric conversion layer 202 and having a conductivity type different therefrom may be provided, and a depletion region may be formed near these semiconductor layers to suppress dark current.

[0104] The high-concentration impurity region 211 arranged to surround the pixel 20 in the pixel boundary region 21 is a region having a higher impurity content per unit volume than the photoelectric conversion layer 202. The high-concentration impurity region 211 is provided mainly to suppress dark current. The high-concentration impurity region 211 may be, for example, a region in which impurities are injected and diffused, or may be a region in which a compound semiconductor layer containing impurities is epitaxially grown from the side wall of a groove formed in the pixel boundary region 21 toward the inside of the pixel 20.

[0105] The pinning electrode 212 is used to induce specific charges (e.g., holes) in the high-concentration impurity region 211. The pinning electrode 212 extends from the side of the pixel 20 opposite to the light incident side to a height at which the pinning electrode 212 does not contact the contact layer 201. The pinning electrode 212 is provided between the high-concentration impurity region 211 and the through electrode 213. Although an insulating material is provided between the pinning electrode 212 and the high-concentration impurity region 211, the charges induced in the high-concentration impurity region 211 can be controlled by controlling the voltage applied to the pinning electrode 212. More specifically, the pinning electrode 212 can induce charges having a polarity opposite to the polarity of the charges transferred to the transfer electrode 205 in the high-concentration impurity region 211.

[0106] The through electrode 213 is an electrode for applying a bias voltage to the contact layer 201. The through electrode 213 is arranged from the side opposite to the light incident side of the pixel 20 to the height of the contact layer 201. In addition, an insulating material is provided between the through electrode 213 and the high concentration impurity region 211.

[0107] like Figure 4B As shown, in Figure 3 The two pinned electrodes 212 arranged in the layer direction in the pixel boundary region 21 of two pixels 20 adjacent in the first direction X in FIG. Figure 3 In the second direction Y, two pinning electrodes 212 are formed in the pixel boundary region 21 of two pixels 20 adjacent to each other.

[0108] Figure 5 2 is a schematic diagram showing a state in which electric charges move in the pixel 20 according to the first embodiment of the present disclosure. Figure 5 The configuration of the pixel 20 and the pixel boundary region 21 shown in FIG. Figure 4A The configuration in FIG. 20 is the same. A reverse bias voltage is applied to the pixel 20 through the contact layers 201 and 204. In addition, the high-concentration impurity region 211 eliminates the charge caused by crystal defects or the like caused by the charge induced in the high-concentration impurity region 211 by the voltage applied to the pinning electrode 212, thereby preventing dark current from being read at the transfer electrode 205. For example, in the case where the transfer electrode 205 transfers electrons, the voltage applied to the pinning electrode 212 is controlled to induce holes in the high-concentration impurity region 211.

[0109] As described above, when a predetermined voltage for reading specific charges (e.g., electrons) is applied to the transfer electrode 205, a potential gradient is generated, and electrons generated by photoelectric conversion are attracted to the transfer electrode 205. The electrons transferred to the transfer electrode 205 undergo charge-voltage conversion in the pixel circuit to generate a pixel signal.

[0110] Fig. 6Ais a cross-sectional view of an imaging device 100 according to a first comparative example, Figure 6B is a cross-sectional view of an imaging device 100 a according to a second comparative example. Fig. 6A and Figure 6B The imaging devices 100 and 100a in the embodiment include pixels 20 in each of which a first semiconductor layer 221, a second semiconductor layer 222, and a photoelectric conversion layer 202 are laminated. Furthermore, in a pixel boundary region 21 between two pixels 20 adjacent to each other, a diffusion layer 223, a coating film, and a protective film are laminated in the pixel boundary region 21 between two pixels 20 adjacent to each other. On the light incident surface side of the photoelectric conversion layer 202, a contact layer 201 is arranged.

[0111] exist Fig. 6A In the imaging device 100, a transparent electrode 224 is provided laminated on the contact layer 201, replacing Figure 4A The through electrode 213 in the Fig. 6A In the embodiment of the present invention, a bias voltage is applied to the contact layer 201 through the transparent electrode 224. In the first comparative example, the pinned electrode 212 is provided in the pixel boundary region 21, and the voltage applied to the pinned electrode 212 is controlled to induce charges of a desired polarity in the diffusion layer 223, so that dark current can be suppressed. However, since the transparent electrode 224 is provided on the light incident surface side of the photoelectric conversion layer 202, the optical characteristics of the imaging device 100 may be deteriorated.

[0112] exist Figure 6B In the imaging device 100a in , the pinning electrode 212 is set to a height at which the pinning electrode 212 reaches the contact layer 201. As a result, the potential of the contact layer 201 can be set by the voltage applied to the pinning electrode 212, and the transparent electrode 224 becomes unnecessary. Therefore, there is no possibility that the optical characteristics of infrared rays are deteriorated due to the transparent electrode 224. However, since the pinning electrode 212 is electrically connected to the contact layer 201, and the contact layer 201 is in contact with the diffusion layer 223, there is a possibility that charges of a desired polarity cannot be induced in the diffusion layer 223. Therefore, the effect of suppressing dark current may not be sufficiently obtained.

[0113] As described above, compared with the first comparative example and the second comparative example, Figure 4A The imaging device 1 according to the first embodiment of the present disclosure shown in FIG. 1 applies a bias voltage to the contact layer 201 not through the transparent electrode 224 but through the through electrode 213 in the pixel boundary region 21. In addition, the high-concentration impurity region 211 is set to an optimal voltage for suppressing dark current by the pinning electrode 212. Therefore, the imaging device 1 according to the first embodiment of the present disclosure can suppress dark current and improve optical characteristics.

[0114] (Step of Manufacturing Imaging Device According to First Embodiment of the Present Disclosure)

[0115] Next, an outline of steps of manufacturing the imaging device 1 according to the first embodiment of the present disclosure will be described. 7A to 7J 1 is a diagram showing steps of manufacturing the imaging device 1 according to the first embodiment of the present disclosure. Fig. 7A As shown in FIG. 4 , a stacked body 4 is formed in which a contact layer 201, a photoelectric conversion layer 202, a contact layer 204 and an insulating layer 41 are stacked in sequence. Figure 7B As shown, a portion of the laminate 4 is removed by etching or the like to form a groove 42. The groove 42 is formed so that the bottom reaches the contact layer 201, and is provided in the pixel boundary region 21. In addition, a groove 43 having a height reaching the contact layer 204 is formed at a position where the transfer electrode 205 is formed. Next, as shown in FIG. Figure 7C As shown, a high-concentration impurity diffusion region (high-concentration impurity region 211) is formed along the sidewall of the trench 42, and impurities are injected into the bottom of the trench 43 to form the impurity diffusion region 203. The polarity of the impurities contained in the high-concentration impurity region 211 and the polarity of the impurities contained in the impurity diffusion region 203 are different from each other. For example, the high-concentration impurity region 211 contains p-type impurities (for example, zinc, magnesium, etc.), and the impurity diffusion region 203 contains n-type impurities (for example, sulfur, germanium, etc.). The amount of impurities per unit volume contained in the high-concentration impurity region 211 is made greater than the amount of impurities per unit volume contained in the photoelectric conversion layer 202. The high-concentration impurity region 211 may be a diffusion region in which impurities are injected from the trench 42 into the sidewall and diffused, or a semiconductor layer containing impurities formed by epitaxial growth from the sidewall of the trench 42. The impurity diffusion region 203 is a diffusion region in which impurities are injected into the bottom of the trench 43 and diffused.

[0116] Next, if Fig.7D and Fig. 7E As shown, the inner walls of the grooves 42 and 43 are covered with an insulating material and then further covered with a metal material. The metal material is used for the pinning electrode 212 and the transmission electrode 205, and is a highly conductive material such as copper or aluminum. Fig.7D It is along Figure 3 A cross-sectional view taken along line AA in FIG. Fig. 7E It is along Figure 3 A cross-sectional view taken along line BB in FIG. Fig.7D and Fig. 7E The transfer electrode 205 is formed in the groove 43. Figure 3 The width of the groove 42 in the AA direction is greater than that of the groove 42 in the Figure 3 The width in the BB direction of the groove 42 is Figure 3 In the AA direction, such as Fig.7D As shown, a groove region 42a not filled with metal material is formed, and as shown in FIG. Fig. 7E As shown, the groove 42 is Figure 3 The inner wall portion along the BB line in the embodiment is filled with metal material. Figure 3 The AA line direction in Fig.7D After the step of, the bottom of the recessed area 42a is dug down by etching or the like to reach the contact layer 201, as shown in FIG. Figure 7F shown.

[0117] Next, if Figure 7G and Figure 7H As shown, the inner wall of the recessed area 42a is covered with an insulating material. Figure 7G It is along Figure 3 A cross-sectional view taken along line AA in FIG. Figure 7H It is along Figure 3 A cross-sectional view taken along line BB in FIG. Figure 7G After the steps, Fig.7I As shown in FIG. 4 , the bottom of the recessed region 42 a is again dug downward by etching or the like to reach the contact layer 201. Next, as shown in FIG. Figure 7J As shown, the interior of the groove region 42 a is filled with a metal material to form a through electrode 213 .

[0118] Fig. 8A and Figure 8B : is a cross-sectional view showing an example of wiring connection between the pixel 20 and the pixel circuit. Fig. 8A and Figure 8B Including features similar to Figure 4A The pixel region 2 and the pixel boundary region 21 of the cross-sectional structure are shown in FIG. Fig. 8A and Figure 8B , the light incident surface is shown on the upper side. Fig. 8A Each pixel 20 includes a first wiring region 51 connected to the transfer electrode 205, a second wiring region 52 connected to the through electrode 213, and a third wiring region 53 connected to the pinning electrode 212. The other ends of the first to third wiring regions 51, 52, and 53 are all connected to the pixel circuit 23. Fig. 8A In the pixel boundary region 21, one second wiring region 52 and two third wiring regions 53 are provided. As described above, since Fig. 8A In the embodiment, the first to third wiring regions 51, 52, and 53 are respectively connected to the transfer electrode 205, the through electrode 213, and the pinning electrode 212 of each pixel 20, so the number of wiring regions increases. Figure 8B is through Fig. 8AThe third wiring region 53 is obtained by thinning the third wiring region 53 in the pixel region 2. The third wiring region 53 is not connected to the pinning electrode 212 except for the peripheral edge portion of the pixel region 2. The wiring region 61 extending outward is connected to the pinning electrode 212 located at the peripheral edge portion of the pixel region 2, and the pinning electrode 212 in each pixel boundary region 21 is set to the same voltage level via the wiring region 61.

[0119] (First Modification of the First Embodiment of the Present Invention)

[0120] Fig. 9 The cross-sectional structure of the imaging device 1 in the first modified example of the first embodiment of the present invention is shown, and is taken along Figure 3 A cross-sectional view taken along line BB in FIG. Fig. 9 In the embodiment, the pinning electrode 212 disposed in the pixel boundary region 21 has a shape similar to that of Figure 4B The shape of the pinning electrode 212 is different. Fig. 9 The pinning electrode 212 in the pixel boundary region 21 is a metal layer arranged along the inner wall of the groove formed in the pixel boundary region 21, and the inside of the metal layer is filled with an insulating material. The pinning electrodes 212 of two adjacent pixels 20 are electrically connected to each other through the metal layer at the bottom of the groove. Fig. 9 Shown in Figure 3 The cross-sectional structure of two of the pixels 20 adjacent in the first direction X is shown in FIG. 1 , but the cross-sectional structure of two of the pixels 20 adjacent in the second direction Y is similar.

[0121] (Second Modification of the First Embodiment of the Present Invention)

[0122] Fig.10 is a plan view of the pixel region 2 in the second variation of the first embodiment of the present invention. Figure 3 Unlike the configuration of the first embodiment of the present disclosure shown in , the pinning electrodes 212 of adjacent pixels 20 are not connected to each other.

[0123] Fig.11 It is along Fig.10 A cross-sectional view taken along line BB in FIG. Fig.11 In, with Figure 4B Differently, the pinned electrodes 212 disposed in the pixel boundary region 21 of two adjacent pixels 20 are separated from each other by an insulating material. Fig.10 The cross-sectional view taken along line AA in is similar to Figure 4A . At this time, the pinning electrode 212 may be individually connected to the pixel circuit of each pixel 20. In addition, a wiring layer may be provided between the pixel circuit and the pinning electrode 212 to connect the pinning electrodes 212 to each other through the wiring layer.

[0124] (Third Modification of the First Embodiment of the Present Invention)

[0125] The pinning electrode 212 needs to be provided for each pixel 20 , but the through-electrode 213 does not need to be provided for each pixel 20 . Fig.12 FIG. 2 is a plan view of the pixel region 2 in the third modified example of the first embodiment of the present invention. Fig.12 In, with Figure 3 Unlike the configuration of the first embodiment of the present disclosure shown in FIG, the through-electrode 213 is disposed at the center portion of four pixels 20 adjacent in the first direction X and the second direction Y, and no other through-electrode 213 exists. Fig.12 In the embodiment, the through-electrodes 213 are provided at a ratio of 1 to 4 adjacent pixels 20 .

[0126] By providing at least one through electrode 213 for four adjacent pixels 20, the voltage level of the contact layer 201 can be set. However, when only one through electrode 213 is provided for four adjacent pixels 20, the conduction of the contact layer 201 becomes incomplete when the through electrode 213 does not reach the contact layer 201 due to manufacturing deviations, etc. Therefore, it is preferable to provide two or more through electrodes 213 in four adjacent pixels 20.

[0127] (Fourth Modification of the First Embodiment of the Present Invention)

[0128] Fig.13 2 is a plan view of the pixel region 2 in the fourth variation of the first embodiment of the present invention. In the fourth variation of the first embodiment of the present disclosure, the through electrodes 213 are arranged in a grid pattern in the pixel boundary region 21. Thus, the through electrodes 213 are symmetrically connected to all the pixels 20, and even if a part of the through electrodes 213 is disconnected, the voltage level of the through electrodes 213 can be shared by all the pixels.

[0129] (Fifth Modification of the First Embodiment of the Present Invention)

[0130] Fig.14 The cross-sectional structure of the imaging device 1 in the fifth modified example of the first embodiment of the present invention is shown, and is taken along Figure 3 The cross-sectional view is taken along the line AA in FIG. Fig.14 As shown, in Fig.14 In the imaging device 1 of FIG. 1 , the through electrode 213 in the pixel boundary region 21 penetrates the contact layer 201. As a result, the light shielding effect is enhanced, so that suppression of color mixing can be expected.

[0131] Fig.14The through-electrode 213 shown can be formed by digging a groove from the opposite surface side relative to the light incident surface and filling the groove with a metal material, or can be formed by digging a groove from the light incident surface side and filling the groove with a metal material. Alternatively, grooves can be dug from both the light incident surface side and the opposite surface side, and the grooves are connected to finally form the through-electrode 213. The step of digging the groove from the light incident surface side can be performed after the pixel chip 11 and the circuit chip 12 are laminated, or can be performed before the pixel chip 11 and the circuit chip 12 are laminated. Fig.14 The through electrode 213 is formed in at least one of a pixel boundary region 21 between two pixels 20 adjacent in the first direction X and a pixel boundary region 21 between two pixels 20 adjacent in the second direction Y. In addition, the length of the through electrode 213 in the depth direction may be different between the pixel boundary region 21 between two pixels 20 adjacent in the first direction X and the pixel boundary region 21 between two pixels 20 adjacent in the second direction Y.

[0132] As described above, in the first embodiment, in the pixel boundary region 21 between two pixels 20 adjacent to each other in the first direction X and the second direction Y, the through electrode 213 electrically connected to the contact layer 201 on the light incident surface side in the pixel 20 is provided, and the pinning electrode 212 for inducing specific charges in the high concentration impurity region 211 provided in the peripheral edge portion of the pixel 20 is provided. By providing the through electrode 213 in the pixel boundary region 21, it is not necessary to provide the transparent electrode 224 on the light incident surface side in the pixel 20, and the optical characteristics of the imaging device 1 can be improved. In addition, by providing the pinning electrode 212 in the pixel boundary region 21, dark current can be suppressed.

[0133] (Second embodiment of the present disclosure)

[0134] Fig.15 and Fig.16 A pixel structure of an imaging device 1 according to a second embodiment of the present disclosure is shown. Fig.15 is a plan view of the pixel region 2. Fig.15The imaging device 1 in the embodiment includes a plurality of pixels 20 arranged two-dimensionally. In addition, a pixel boundary region 24 is provided between two pixels 20 arranged adjacent to each other in the first direction X and between two pixels 20 arranged adjacent to each other in the second direction Y. In the pixel boundary region 24, a high-concentration impurity region 241, a pinning electrode 242 (third electrode), and an electrode 243 (fourth electrode) are provided. The electrode 243 is provided to surround the high-concentration impurity region 241. As described later, the electrode 243 is connected to the high-concentration impurity region 241. The pinning electrode 242 is arranged in a lattice pattern to surround the pixel 20 and the high-concentration impurity region 241. The pinning electrodes 242 of the corresponding pixels 20 arranged in the pixel boundary region 24 in the first direction X and the second direction Y are connected to each other.

[0135] Fig.16 It is along Fig.15 Cross-sectional view taken along line CC in FIG. Fig.16 2 shows a cross-sectional structure of two of the pixels 20 adjacent to each other in the first direction X. Fig.16 , the light incident surface is illustrated on the underside. Fig.16 The configuration of the pixel 20 in Figure 4A The configuration of the pixel 20 of the first embodiment of the present disclosure shown in FIG. Fig.16 In the pixel boundary region 24 in FIG. 1 , a high-concentration impurity region 241 , a pinning electrode 242 (third electrode) and an electrode 243 (fourth electrode) are provided.

[0136] The electrode 243 is provided to establish conduction with the contact layer 201, and the voltage level of the contact layer 201 can be set by applying a predetermined voltage to the electrode 243. The electrode 243 is provided on the opposite surface side relative to the light incident surface side of the pixel 20 and is connected to the high concentration impurity region 241. The high concentration impurity region 241 is connected to the contact layer 201. Therefore, the electrode 243 is electrically connected to the contact layer 201 through the high concentration impurity region 241. The details of the high concentration impurity region 241 are similar to Figure 4A Details of the high-concentration impurity region 211 in FIG. 24 are shown, and the high-concentration impurity region 241 contains impurities at a high concentration to such an extent that the impurity has conductivity.

[0137] The pinning electrode 242 is used to induce specific charges (for example, holes) in the high concentration impurity region 241. The pinning electrode 242 is arranged to surround the high concentration impurity region 241. In addition, between the pinning electrode 242 and each of the electrode 243 and the high concentration impurity region 241, an insulating material is provided.

[0138] As mentioned above, in Fig.16In the imaging device 1 according to the second embodiment of the present disclosure shown, conduction with the contact layer 201 is established by the electrode 243 provided in the pixel boundary region 24 and the high concentration impurity region 241. In addition, specific charges are induced in the high concentration impurity region 241 by the pinning electrode 242 provided in the pixel boundary region 24.

[0139] (Step of Manufacturing Imaging Device According to Second Embodiment of the Present Disclosure)

[0140] Next, an outline of the steps of manufacturing the imaging device 1 according to the second embodiment of the present disclosure will be described. The steps from the formation of the laminate 4 as a substrate, the formation of the grooves as the pixel boundary region 24, and the diffusion of impurities are similar to the manufacturing steps of the first embodiment of the present disclosure ( Figures 7A to 7C ).

[0141] When completed Figure 7C Step 1, then, Fig.17A As shown, covered with insulating material Figure 7C The inner walls of the grooves 42 and 43 formed in the embodiment are formed by coating the insulating material with a metal material. The metal material is used for the pinning electrode 242 and the transmission electrode 205, and is, for example, a highly conductive material such as copper or aluminum. Fig. 17B As shown in FIG. 2 , an insulating layer 41a is formed on the opposite side of the contact layer 201. Fig. 17C In the step of partially removing the Fig. 17B The insulating layer 41a is formed in the groove portion 40a and 40b. Fig.17D As shown in FIG. 2 , the groove portion 40a is further excavated to form a groove 44. Thus, the bottom of the groove 44 reaches the high-concentration impurity region 241. Similarly, the groove portion 40b is further excavated at the portion where the transfer electrode 205 is formed to form a groove 45. On the other hand, the insulating layer 41a remains on the side of the pinning electrode 242 opposite to the light incident surface. Next, Fig.17E In the step of filling with metal material Fig.17D The metal material in the groove 44 forms the electrode 243 , and the metal material in the groove 45 increases the thickness of the transfer electrode 205 .

[0142] Fig.18A and Fig.18B 2 is a cross-sectional view showing an example of wiring connection between the pixel 20 and the pixel circuit 23 according to the second embodiment of the present disclosure. Fig.18A and Fig.18B In FIG. 1 , the light incident rear surface side is shown on the upper side. Fig.18A In, with Figure 8BSimilar to the wiring example of the first embodiment of the present disclosure shown in FIG, a first wiring region 51 and a second wiring region 52 are provided for each pixel 20. The second wiring region 52 is connected to the electrode 243 of each pixel 20. Fig.18A In the wiring example shown in , the pinning electrodes 242 of the respective pixels 20 are electrically connected to each other, for example, in the pixel boundary region 24 or in a wiring layer (not shown). Fig.18A In the embodiment, the pinning electrode 242 in the pixel boundary region 24 on the peripheral edge side of the pixel region 2 is connected to the wiring region 61 extending to the peripheral side, and in the wiring region 61, the pinning electrodes 242 of each pixel 20 are set to the same voltage level.

[0143] Fig.18B Shown with Fig.18A Compared to the cross-sectional structure, the number of wiring areas is reduced. Fig.18B In the embodiment, the wiring region is not connected to the electrode 243 in the pixel boundary region 24 except the pixel boundary region 24 on the peripheral edge side of the pixel region 2. The wiring region 62 extending to the peripheral side is connected to the electrode 243 in the pixel boundary region 24 located on the edge side, and in the wiring region 62, the electrode 243 and the contact layer 201 of each pixel 20 are set to the same voltage level.

[0144] (First Modification of the Second Embodiment of the Present Disclosure)

[0145] Fig.19 2 is a cross-sectional view of an imaging device 1 according to a first variation of the second embodiment of the present invention. The first variation of the second embodiment of the present disclosure is characterized in that the pixel boundary region 24 is formed from the light incident surface side. Fig.19 In the imaging device 1 in , a groove is formed from the contact layer 201 side in the pixel boundary region 24. As a result, the pinned electrode 242 and the high-concentration impurity region 241 penetrate the contact layer 201.

[0146] (Second Modification of the Second Embodiment of the Present Disclosure)

[0147] Fig. 20 2 is a cross-sectional view of an imaging device 1 according to a second modified example of the second embodiment of the present invention. Fig. 20 The imaging device 1 illustrated in FIG. Fig.15 The polarity of the imaging device 1 illustrated in FIG. 1 is opposite to the polarity of each layer. Fig.15 The imaging device 1 in the embodiment transfers the electrons generated in the photoelectric conversion layer 202 to the transfer electrode 205, and Fig. 20 The imaging device 1 in FIG. 1 transfers holes generated in the photoelectric conversion layer 202 to the transfer electrode 205. Fig.15 and 20In the embodiment, the polarity of the charge induced in the high concentration impurity region 241 is also opposite. More specifically, Fig. 20 The high-concentration impurity region 241 in the embodiment contains a large amount of n-type impurities (eg, sulfur, germanium, etc.), and the impurity diffusion region 203 contains a large amount of p-type impurities (eg, zinc, magnesium, etc.).

[0148] As described above, in the second embodiment, the high-concentration impurity region 241 provided in the pixel boundary region 24 is connected to the contact layer 201 at the end on the light incident surface side, and the high-concentration impurity region 241 is connected to the electrode 243 at the end on the opposite surface side relative to the light incident surface. Therefore, the voltage level of the contact layer 201 can be set by the voltage applied to the electrode 243, and there is no need to provide the transparent electrode 224 on the light incident surface side of the pixel 20. In addition, since the pinning electrode 242 is arranged in the pixel boundary region 24 so as to be separated from the high-concentration impurity region 241, specific charges can be induced in the high-concentration impurity region 241 by controlling the voltage applied to the pinning electrode 242, and dark current can be suppressed.

[0149] (Application example)

[0150] The technology according to the present disclosure can be applied to various products. For example, the technology according to the present disclosure can also be implemented as a device installed on any kind of mobile body such as a car, an electric vehicle, a hybrid electric vehicle, a motorcycle, a bicycle, personal mobility, an airplane, a drone, a ship, a robot, a construction machine, an agricultural machine (tractor), etc.

[0151] Fig.21 7000 is a block diagram showing a schematic configuration example of a vehicle control system 7000 as an example of a mobile body control system to which the technology according to the present disclosure can be applied. The vehicle control system 7000 includes a plurality of electronic control units connected to each other via a communication network 7010. Fig.21 In the example shown, the vehicle control system 7000 includes a drive system control unit 7100, a body system control unit 7200, a battery control unit 7300, an external information detection unit 7400, an internal information detection unit 7500, and an integrated control unit 7600. For example, the communication network 7010 connecting the plurality of control units to each other may be an in-vehicle communication network conforming to any standard, such as a controller area network (CAN), a local interconnect network (LIN), a local area network (LAN), FlexRay (registered trademark), and the like.

[0152] Each control unit includes: a microcomputer that performs calculations according to various programs; a memory that stores programs executed by the microcomputer, parameters for various calculations, etc.; and a drive circuit that drives various control object devices. Each control unit includes a network I / F for communicating with other control units via the communication network 7010, and a communication I / F for communicating with devices, sensors, etc. inside and outside the vehicle through wired or wireless communication. Fig.21 76, as a functional configuration of an integrated control unit 7600, a microcomputer 7610, a general communication I / F 7620, a dedicated communication I / F 7630, a positioning unit 7640, a beacon receiving unit 7650, an in-vehicle device I / F 7660, a sound / image output unit 7670, an in-vehicle network I / F 7680, and a memory 7690 are shown. Other control units similarly include a microcomputer, a communication I / F, a memory, and the like.

[0153] The drive system control unit 7100 controls the operation of devices related to the drive system of the vehicle according to various programs. For example, the drive system control unit 7100 functions as a control device for a drive force generating device (such as an internal combustion engine, a drive motor, etc.) for generating the drive force of the vehicle, a drive force transmission mechanism for transmitting the drive force to the wheels, a steering mechanism for adjusting the steering angle of the vehicle, a braking device for generating the braking force of the vehicle, etc. The drive system control unit 7100 may have a function as a control device for an anti-lock braking system (ABS), an electronic stability control (ESC), etc.

[0154] The drive system control unit 7100 is connected to the vehicle state detection unit 7110. The vehicle state detection unit 7110 includes, for example, a gyro sensor for detecting the angular velocity of the axial rotational motion of the vehicle body, an acceleration sensor for detecting the acceleration of the vehicle, and at least one of sensors for detecting the operation amount of the accelerator pedal, the operation amount of the brake pedal, the steering angle of the steering wheel, the engine speed, or the wheel speed. The drive system control unit 7100 performs calculation processing using the signal input from the vehicle state detection unit 7110 to control the internal combustion engine, the drive motor, the electric power steering device, the brake device, etc.

[0155] The body system control unit 7200 controls the operation of various devices provided in the body according to various programs. For example, the body system control unit 7200 is used as a control device for a keyless entry system, a smart key system, a power window device, or various lights such as a headlight, a backup light, a brake light, a turn signal, a fog light, etc. In this case, a radio wave emitted from a mobile device may be input to the body system control unit 7200 as a substitute for a signal of a key or various switches. The body system control unit 7200 receives these input radio waves or signals, and controls a door lock device, a power window device, lights, etc. of the vehicle.

[0156] The battery control unit 7300 controls the secondary battery 7310 as a power source for driving the motor according to various programs. For example, information about the battery temperature, the battery output voltage, the amount of charge remaining in the battery, etc. is supplied to the battery control unit 7300 from the battery device including the secondary battery 7310. The battery control unit 7300 performs arithmetic operation processing using these signals, and performs control for adjusting the temperature of the secondary battery 7310 or controls a cooling device provided to the battery device, etc.

[0157] The vehicle exterior information detection unit 7400 detects information outside the vehicle including the vehicle control system 7000. For example, the vehicle exterior information detection unit 7400 is connected to at least one of the imaging unit 7410 and the vehicle exterior information detection unit 7420. The imaging unit 7410 includes at least one of a time-of-flight (ToF) camera, a stereo camera, a monocular camera, an infrared camera, and other cameras. For example, the vehicle exterior information detection unit 7420 includes at least one of an environmental sensor for detecting current atmospheric conditions or weather conditions, and a peripheral information detection sensor for detecting another vehicle, an obstacle, a pedestrian, etc. around the vehicle including the vehicle control system 7000.

[0158] For example, the environmental sensor may be at least one of a raindrop sensor for detecting rain, a fog sensor for detecting fog, a sunlight sensor for detecting sunlight levels, or a snow sensor for detecting snowfall. The peripheral information detection sensor may be at least one of an ultrasonic sensor, a radar device, a light detection and ranging device, or a laser imaging detection and ranging device (LIDAR device). Each of the imaging unit 7410 and the vehicle exterior information detection unit 7420 may be provided as an independent sensor or device, or may be provided as a device in which a plurality of sensors or devices are integrated.

[0159] Here, Fig. 22An example of the installation position of the imaging unit 7410 and the vehicle exterior information detection unit 7420 is shown. The imaging units 7910, 7912, 7914, 7916, and 7918 are installed in at least one of the front nose, side mirrors, rear bumper, rear door, and upper portion of the windshield in the vehicle 7900. The imaging unit 7910 installed in the front nose of the vehicle and the imaging unit 7918 installed in the upper portion of the windshield mainly capture images in front of the vehicle 7900. The imaging units 7912 and 7914 installed in the side mirrors mainly capture images of the side of the vehicle 7900. The imaging unit 7916 installed in the rear bumper or rear door mainly captures images of the rear of the vehicle 7900. The imaging unit 7918 installed in the upper portion of the windshield in the vehicle is mainly used to detect vehicles in front, pedestrians, obstacles, traffic lights, traffic signs, lanes, etc.

[0160] Notice, Fig. 22 7910, 7912, 7914, and 7916. An example of the imaging range of each of the imaging units 7910, 7912, 7914, and 7916 is shown. The imaging range a represents the imaging range of the imaging unit 7910 provided on the front nose, the imaging ranges b and c represent the imaging ranges of the imaging units 7912 and 7914 provided on the side mirrors, respectively, and the imaging range d represents the imaging range of the imaging unit 7916 provided on the rear bumper or the rear door. The bird's-eye view image of the vehicle 7900 can be obtained, for example, by overlapping the image data captured by the imaging units 7910, 7912, 7914, and 7916.

[0161] The vehicle exterior information detection units 7920, 7922, 7924, 7926, 7928, 7930 provided at the front, rear, side, corner, and upper portion of the windshield in the vehicle 7900 may be, for example, ultrasonic sensors or radar devices. In addition, the vehicle exterior information detection units 7920, 7926, 7930 provided at the front nose, rear bumper, rear door, and upper portion of the windshield in the vehicle 7900 may be, for example, LIDAR devices. These vehicle exterior information detection units 7920 to 7930 are mainly used to detect preceding vehicles, pedestrians, obstacles, and the like.

[0162] Return to see Fig.21, will continue to describe. The vehicle exterior information detection unit 7400 enables the imaging unit 7410 to capture images outside the vehicle and receive captured image data. In addition, the vehicle exterior information detection unit 7400 receives detection information from the vehicle exterior information detection unit 7420 connected to the vehicle exterior information detection unit 7400. In the case where the vehicle exterior information detection unit 7420 is an ultrasonic sensor, a radar device, or a LIDAR device, ultrasonic waves, electromagnetic waves, etc. are transmitted, and information of received reflected waves is received. Based on the received information, the vehicle exterior information detection unit 7400 can perform processing for detecting objects such as people, vehicles, obstacles, signs, and text on the road surface, or processing for detecting the distance between objects. In addition, the vehicle exterior information detection unit 7400 can also perform environmental recognition processing for identifying rainfall, fog, road conditions, etc. based on the received information. The vehicle exterior information detection unit 7400 can calculate the distance to objects outside the vehicle based on the received information.

[0163] In addition, the vehicle exterior information detection unit 7400 can perform image recognition processing to identify humans, vehicles, obstacles, signs, text on the road surface, etc., or detect their distances based on the received image data. In addition, the vehicle exterior information detection unit 7400 can also perform distortion correction, alignment and other processing on the received image data, and combine the image data of images captured by different multiple imaging units 7410 to generate a bird's-eye view image or a panoramic image. In addition, the vehicle exterior information detection unit 7400 can also use the image data of images captured by different imaging units 7410 to perform viewpoint transformation processing.

[0164] The in-vehicle information detection unit 7500 detects information related to the interior of the vehicle. The in-vehicle information detection unit 7500 is connected, for example, to a driver state detection unit 7510 that detects the state of the driver. The driver state detection unit 7510 may include a camera that images the driver, a biosensor that detects the driver's biometric information, a microphone that collects sounds inside the vehicle, and the like. The biosensor is, for example, disposed in a seat surface, a steering wheel, and the like, and detects biometric information of a passenger sitting on the seat or a driver holding the steering wheel. Based on the detection information input from the driver state detection unit 7510, the in-vehicle information detection unit 7500 may calculate the driver's fatigue or the driver's concentration, or may determine whether the driver is dozing off. The in-vehicle information detection unit 7500 may perform processing such as noise elimination processing on the audio signal obtained by collecting the sound.

[0165] The integrated control unit 7600 controls the overall operation in the vehicle control system 7000 according to various programs. The integrated control unit 7600 is connected to the input unit 7800. The input unit 7800 is implemented by a device that can be operated by an occupant, such as a touch panel, a button, a microphone, a switch, a joystick, etc. The integrated control unit 7600 may be supplied with data obtained by voice recognition of a voice input through a microphone. The input unit 7800 may be, for example, a remote control device using infrared or other radio waves, or an external connection device that supports the operation of the vehicle control system 7000, such as a mobile phone, a personal digital assistant (PDA), etc. The input unit 7800 may be, for example, a camera. In this case, the occupant may input information by gestures. Alternatively, data obtained by detecting the movement of a wearable device worn by the occupant may be input. In addition, the input unit 7800 may include, for example, an input control circuit, etc., which generates an input signal based on information input by the occupant, etc. using the above-mentioned input unit 7800, and outputs the generated input signal to the integrated control unit 7600. An occupant or the like inputs various data to the vehicle control system 7000 or gives instructions for processing operations by operating the input unit 7800 .

[0166] The memory 7690 may include a read-only memory (ROM) storing various programs executed by the microcomputer and a random access memory (RAM) storing various parameters, operation results, sensor values, etc. In addition, the memory 7690 may be implemented by a magnetic storage device such as a hard disk drive (HDD), a semiconductor storage device, an optical storage device, a magneto-optical storage device, etc.

[0167] The general communication I / F 7620 is a general communication I / F that mediates communication with various devices present in the external environment 7750. The general communication I / F 7620 can implement a cellular communication protocol such as Global System for Mobile Communications (GSM) (registered trademark), Worldwide Interoperability for Microwave Access (WiMAX (registered trademark)), Long Term Evolution (LTE (registered trademark)), or LTE-Advanced (LTE-A), or another wireless communication protocol such as a wireless LAN (also known as Wireless Fidelity (Wi-Fi) (registered trademark)) or Bluetooth (registered trademark). For example, the general communication I / F 7620 can be connected to a device (e.g., an application server or a control server) present in an external network (e.g., the Internet, a cloud network, or a company-specific network) via a base station or an access point. In addition, for example, the general communication I / F 7620 can be connected to a terminal (e.g., a driver's terminal, a pedestrian or a store, or a machine type communication (MTC) terminal) present near the vehicle using a peer-to-peer (P2P) technology.

[0168] The dedicated communication I / F 7630 is a communication I / F that supports the development of a communication protocol for use in a vehicle. The dedicated communication I / F 7630 may implement a standard protocol such as Wireless Access in Vehicular Environments (WAVE) (which is a combination of Institute of Electrical and Electronics Engineers (IEEE) 802.11p as a lower layer and IEEE 1609 as a higher layer), Dedicated Short Range Communication (DSRC), or a cellular communication protocol. The dedicated communication I / F 7630 generally performs V2X communication as a concept including one or more of the following: communication between vehicles and vehicles (vehicle to vehicle), communication between roads and vehicles (vehicle to infrastructure), communication between vehicles and homes (vehicle to home), and communication between pedestrians and vehicles (vehicle to pedestrians).

[0169] The positioning unit 7640 performs positioning, for example, by receiving a global navigation satellite system (GNSS) signal (e.g., a GPS signal from a global positioning system (GPS) satellite) from a GNSS satellite, and generates position information including the latitude, longitude, and altitude of the vehicle. Incidentally, the positioning unit 7640 can identify the current position by exchanging signals with a wireless access point, or can obtain position information from a terminal such as a mobile phone, a personal handyphone system (PHS), or a smart phone with a positioning function.

[0170] For example, the beacon receiving unit 7650 receives radio waves or electromagnetic waves transmitted from a radio station installed on a road or the like, and thereby obtains information on the current position, congestion, closed roads, required time, etc. Incidentally, the function of the beacon receiving unit 7650 may be included in the above-mentioned dedicated communication I / F 7630.

[0171] The vehicle-mounted device I / F 7660 is a communication interface for mediating the connection between the microcomputer 7610 and the various vehicle-mounted devices 7760 present in the vehicle. The vehicle-mounted device I / F 7660 can establish a wireless connection using a wireless communication protocol such as wireless LAN, Bluetooth (registered trademark), near field communication (NFC) or wireless universal serial bus (WUSB). In addition, the vehicle-mounted device I / F 7660 can establish a wired connection via a universal serial bus (USB), a high-definition multimedia interface (HDMI (registered trademark)), a mobile high-definition link (MHL), etc. via a connection terminal (and a cable, if necessary) not shown in the figure. The vehicle-mounted device 7760 may, for example, include at least one of a mobile device or a wearable device owned by an occupant, or an information device carried or attached to the vehicle. In addition, the vehicle-mounted device 7760 may also include a navigation device for searching a path to an arbitrary destination. The vehicle-mounted device I / F 7660 exchanges control signals or data signals with these vehicle-mounted devices 7760.

[0172] The in-vehicle network I / F 7680 is an interface that mediates communication between the microcomputer 7610 and the communication network 7010. The in-vehicle network I / F 7680 transmits and receives signals and the like according to a predetermined protocol supported by the communication network 7010.

[0173] The microcomputer 7610 of the integrated control unit 7600 controls the vehicle control system 7000 according to various programs based on information obtained via at least one of the general communication I / F 7620, the dedicated communication I / F 7630, the positioning unit 7640, the beacon receiving unit 7650, the vehicle-mounted device I / F 7660, and the vehicle-mounted network I / F 7680. For example, the microcomputer 7610 may calculate a control target value of a driving force generating device, a steering mechanism, or a braking device based on the obtained information about the inside and outside of the vehicle, and output a control command to the drive system control unit 7100. For example, the microcomputer 7610 may perform cooperative control aimed at realizing functions of an advanced driver assistance system (ADAS), including collision prevention or shock absorption for a vehicle, follow-up driving based on a following distance, vehicle speed maintenance for driving, warning of a vehicle collision, warning of a vehicle deviation from a lane, and the like. In addition, the microcomputer 7610 can perform cooperative control for autonomous driving by controlling the drive force generating device, steering mechanism, braking device, etc. based on the information obtained about the surroundings of the vehicle, which enables the vehicle to drive autonomously without relying on the driver's operation, etc.

[0174] The microcomputer 7610 may generate three-dimensional distance information between the vehicle and objects such as surrounding structures, people, etc., and generate local map information including information about the surroundings of the current position of the vehicle based on information obtained via at least one of the general communication I / F 7620, the dedicated communication I / F 7630, the positioning unit 7640, the beacon receiving unit 7650, the vehicle-mounted device I / F 7660, and the vehicle-mounted network I / F 7680. In addition, the microcomputer 7610 may predict dangers such as collision of vehicles, approach of pedestrians, etc., entering a closed road, etc. based on the obtained information, and generate a warning signal. The warning signal may be, for example, a signal for generating a warning sound or lighting a warning light.

[0175] The sound / image output unit 7670 transmits an output signal of at least one of sound and image to an output device that can visually or auditorily notify the occupants of the vehicle or the outside of the vehicle of information. Fig.21In an embodiment of the invention, an audio speaker 7710, a display unit 7720, and an instrument panel 7730 are illustrated as output devices. The display unit 7720 may include, for example, at least one of an onboard display or a head-up display. The display unit 7720 may have an augmented reality (AR) display function. The output device may be different from these devices, and may be another device such as headphones, a wearable device such as a glasses-type display worn by a passenger, a projector, a lamp, etc. In the case where the output device is a display device, the display device visually displays the results obtained by various processes performed by the microcomputer 7610 or information received from another control unit in various forms such as text, images, tables, graphics, etc. In addition, in the case where the output device is an audio output device, the audio output device converts an audio signal consisting of reproduced audio data or sound data, etc. into an analog signal, and outputs the analog signal audibly.

[0176] Note that Fig.21 In the illustrated embodiment, at least two control units connected to each other via the communication network 7010 may be integrated into one control unit. Alternatively, each individual control unit may include a plurality of control units. In addition, the vehicle control system 7000 may include another control unit not shown in the figure. In addition, part or all of the functions performed by one of the control units described above may be assigned to another control unit. In other words, as long as information is sent and received via the communication network 7010, predetermined arithmetic processing may be performed by any control unit. Similarly, a sensor or device connected to one of the control units may be connected to another control unit, and a plurality of control units may send and receive detection information to each other via the communication network 7010.

[0177] It should be noted that the present technology can have the following configurations.

[0178] (1) An imaging device comprising:

[0179] A plurality of pixels; and

[0180] A pixel boundary region is set between two adjacent pixels, where

[0181] Each of the plurality of pixels includes:

[0182] A photoelectric conversion layer comprising a compound semiconductor material;

[0183] a first electrode provided on the light incident surface side of the photoelectric conversion layer and containing a compound semiconductor material; and

[0184] a second electrode which is provided on the opposite surface side with respect to the light incident surface side of the photoelectric conversion layer and transfers the charges photoelectrically converted in the photoelectric conversion layer, and

[0185] The pixel boundary area includes:

[0186] A high-concentration impurity region extending from the light incident surface side to the opposite surface side;

[0187] A third electrode electrically insulated from the high-concentration impurity region and disposed along the high-concentration impurity region; and

[0188] A fourth electrode is electrically connected to the first electrode.

[0189] (2) The imaging device according to (1), wherein the high-concentration impurity region has a higher impurity content per unit volume than the photoelectric conversion layer.

[0190] (3) The imaging device according to (1) or (2), wherein the third electrode is set to a voltage that induces specific charges in the high-concentration impurity region.

[0191] (4) The imaging device according to (3), wherein the specific charge is a charge having a polarity different from a polarity of a charge photoelectrically converted in the photoelectric conversion layer and transferred to the second electrode.

[0192] (5) The imaging device according to any one of (1) to (4), wherein

[0193] The first electrode is a semiconductor layer including a compound semiconductor material different from the compound semiconductor material of the photoelectric conversion layer.

[0194] (6) The imaging device according to any one of (1) to (5),

[0195] The fourth electrode is provided at a height from the opposite side to the light incident surface side of the photoelectric conversion layer to the height reaching the first electrode.

[0196] (7) The imaging device according to (6), wherein the third electrode is provided between the fourth electrode and the high-concentration impurity region.

[0197] (8) The imaging device according to (6) or (7), wherein the third electrode is provided from the opposite surface side with respect to the light incident surface side of the photoelectric conversion layer to a height that does not reach the first electrode.

[0198] (9) The imaging device according to any one of (6) to (8), wherein the high-concentration impurity region is provided to surround the pixel, and

[0199] The third electrode is provided to surround the high-concentration impurity region for each of the plurality of pixels.

[0200] (10) The imaging device according to any one of (6) to (9), wherein

[0201] A plurality of pixels are arranged in a first direction and a second direction,

[0202] Two third electrodes included in two pixels disposed adjacent to each other in the first direction are connected at a pixel boundary region between the two pixels disposed adjacent to each other in the first direction, and

[0203] Two third electrodes included in two pixels disposed adjacent to each other in the second direction are connected at a pixel boundary region between the two pixels disposed adjacent to each other in the second direction.

[0204] (11) The imaging device according to any one of (6) to (10), wherein

[0205] The fourth electrode is disposed in a pixel boundary region between two pixels disposed adjacent to each other in a diagonal direction.

[0206] (12) The imaging device according to any one of (6) to (11), further comprising:

[0207] The wiring layer is provided on the opposite side of the light incident surface of the photoelectric conversion layer, wherein

[0208] For each of the plurality of pixels, the wiring layer includes:

[0209] A first wiring region electrically connected to the second electrode; and

[0210] A second wiring region electrically connected to the fourth electrode.

[0211] (13) The imaging device according to (12), wherein, for each of the plurality of pixels, the wiring layer includes a third wiring region electrically connected to the third electrode.

[0212] (14) The imaging device according to any one of (1) to (5), wherein

[0213] An end portion of the high-concentration impurity region on the light incident surface side is connected to the first electrode, and

[0214] An end portion of the high-concentration impurity region on the opposite surface side to the light incident surface side is connected to the fourth electrode.

[0215] (15) The imaging device according to (14), wherein

[0216] A high-concentration impurity region is provided to surround the pixel, and

[0217] The fourth electrode is provided to surround the high-concentration impurity region for each of the plurality of pixels.

[0218] (16) The imaging device according to (14) or (15), wherein

[0219] The third electrode is disposed in a lattice pattern in a plurality of pixel boundary regions between the plurality of pixels.

[0220] (17) The imaging device according to any one of (14) to (16), further comprising a wiring layer provided on the opposite side of the photoelectric conversion layer to the light incident side, wherein

[0221] For each of the plurality of pixels, the wiring layer includes a first wiring region that is electrically connected to the second electrode.

[0222] (18) The imaging device according to (17), wherein

[0223] For each of the plurality of pixels, the wiring layer includes a second wiring region that is electrically connected to the fourth electrode.

[0224] (19) The imaging device according to any one of (1) to (18), wherein

[0225] A plurality of third electrodes disposed in a plurality of pixel boundary regions between a plurality of pixels are electrically connected to each other, and

[0226] The plurality of fourth electrodes disposed in the plurality of pixel boundary regions are electrically connected to each other.

[0227] The various aspects of the present disclosure are not limited to the above-mentioned embodiments, but include various modifications that can be thought of by those skilled in the art, and the effects of the present disclosure are not limited to the above-mentioned contents. That is, various additions, modifications, and partial deletions may be made without departing from the concept and spirit of the present disclosure obtained from the contents defined in the claims and their equivalents.

[0228] Reference Symbols List

[0229] 1,100,100a Imaging device

[0230] 2 pixel area

[0231] 3 Circuit unit

[0232] 4 Laminate

[0233] 11 Pixel Chip

[0234] 12 Circuit Chip

[0235] 20 pixels

[0236] 21, 24 pixel border area

[0237] 23 Pixel Circuit

[0238] 31 line scanning unit

[0239] 32 Horizontal Selection Units

[0240] 33 column scanning unit

[0241] 34 System Control Unit

[0242] 35 pixel drive lines

[0243] 36, 37 signal lines

[0244] 40a, 40b groove portion

[0245] 41, 41a Insulation layer

[0246] Grooves 42, 43, 44, 45

[0247] 42a Groove area

[0248] 51 First wiring area

[0249] 52 Second wiring area

[0250] 53 Third wiring area

[0251] 61, 62 wiring area

[0252] 201, 204 contact layer

[0253] 202 Photoelectric conversion layer

[0254] 203 Impurity Diffusion Region

[0255] 205 Transfer Electrode

[0256] 211, 241 High concentration impurity area

[0257] 212, 242 Pinning Electrode

[0258] 213 Through electrode

[0259] 221 First semiconductor layer

[0260] 222 Second semiconductor layer

[0261] 223 Diffusion layer

[0262] 224 Transparent Electrode

[0263] 243 Electrode

Claims

1. An imaging device, include: Multiple pixels; as well as A pixel boundary region is set between two adjacent pixels, where Each of the plurality of pixels comprises: A photoelectric conversion layer comprising a compound semiconductor material; a first electrode provided on the light incident surface side of the photoelectric conversion layer and comprising a compound semiconductor material; and a second electrode which is provided on the opposite surface side with respect to the light incident surface side of the photoelectric conversion layer and transfers the charges photoelectrically converted in the photoelectric conversion layer, and The pixel boundary area includes: A high-concentration impurity region extending from the light incident surface side to the opposite surface side; a third electrode electrically insulated from the high-concentration impurity region and disposed along the high-concentration impurity region; and A fourth electrode is electrically connected to the first electrode.

2. The imaging device according to claim 1, in, The high-concentration impurity region has a higher impurity content per unit volume than the photoelectric conversion layer.

3. The imaging device according to claim 1, in, The third electrode is set to a voltage that induces specific charges in the high-concentration impurity region.

4. The imaging device according to claim 3, in, The specific charges are charges having a polarity different from a polarity of charges photoelectrically converted in the photoelectric conversion layer and transferred to the second electrode.

5. The imaging device according to claim 1, wherein The first electrode is a semiconductor layer including a compound semiconductor material different from a compound semiconductor material of the photoelectric conversion layer.

6. The imaging device according to claim 1, in, The fourth electrode is provided at a height from the opposite surface side to the light incident surface side of the photoelectric conversion layer to the first electrode.

7. The imaging device according to claim 6, in, The third electrode is provided between the fourth electrode and the high-concentration impurity region.

8. The imaging device according to claim 6, in, The third electrode is provided from the opposite surface side with respect to the light incident surface side of the photoelectric conversion layer to a height that does not reach the first electrode.

9. The imaging device according to claim 6, in, The high-concentration impurity region is provided to surround the pixel, and The third electrode is provided to surround the high-concentration impurity region for each of the plurality of pixels.

10. The imaging device according to claim 6, wherein The plurality of pixels are arranged in a first direction and a second direction, Two third electrodes included in two pixels disposed adjacent to each other in the first direction are connected at a pixel boundary region between the two pixels disposed adjacent to each other in the first direction, and Two third electrodes included in two pixels disposed adjacent to each other in the second direction are connected at a pixel boundary region between the two pixels disposed adjacent to each other in the second direction.

11. The imaging device according to claim 6, wherein The fourth electrode is disposed in a pixel boundary region between two pixels disposed adjacent to each other in a diagonal direction.

12. The imaging device according to claim 6, further comprising a wiring layer provided on the opposite surface side with respect to the light incident surface side of the photoelectric conversion layer, wherein For each of the plurality of pixels, a wiring layer include: a first wiring region electrically connected to the second electrode; as well as A second wiring region electrically connected to the fourth electrode.

13. The imaging device according to claim 12, in, For each of the plurality of pixels, the wiring layer includes a third wiring region that is electrically connected to the third electrode.

14. The imaging device according to claim 1, wherein an end portion of the high-concentration impurity region on the light incident surface side is connected to the first electrode, and An end portion of the high-concentration impurity region on the opposite side to the light incident surface is connected to the fourth electrode.

15. The imaging device according to claim 14, wherein The high-concentration impurity region is provided to surround the pixel, and The fourth electrode is provided to surround the high-concentration impurity region for each of the plurality of pixels.

16. The imaging device according to claim 14, wherein The third electrode is disposed in a lattice pattern in a plurality of pixel boundary regions between the plurality of pixels.

17. The imaging device according to claim 14, further comprising a wiring layer provided on the opposite surface side with respect to the light incident surface side of the photoelectric conversion layer, wherein For each of the plurality of pixels, the wiring layer includes a first wiring region that is electrically connected to the second electrode.

18. The imaging device according to claim 17, wherein For each of the plurality of pixels, the wiring layer includes a second wiring region that is electrically connected to the fourth electrode.

19. The imaging device according to claim 1, wherein A plurality of third electrodes disposed in a plurality of pixel boundary regions between the plurality of pixels are electrically connected to each other, and The plurality of fourth electrodes disposed in the plurality of pixel boundary regions are electrically connected to each other.

Images