Light detection device and electronic equipment

Abstract

A light detection device according to an embodiment of the present disclosure comprises: a first region having a plurality of first pixels, each including a first photoelectric conversion element provided in a semiconductor layer, and a first trench provided between the plurality of first pixels adjacent to each other in the semiconductor layer; and a second region having a second trench provided in a first direction and a second direction intersecting the first direction in the semiconductor layer, and provided around the first region. A pattern density of the second trench is larger than a pattern density of the first trench.

Description

Photodetector and electronic equipment

[0001] The present disclosure relates to photodetection devices and electronic equipment.

[0002] A device has been proposed that has an effective pixel area and a dummy pixel area that is provided so as to surround the effective pixel area on all four sides, and that has an FTI (Full Trench Isolation) structure (Patent Document 1).

[0003] Japanese Patent Application Laid-Open No. 2022-106021

[0004] Light-detecting devices are required to minimize degradation of quality.

[0005] It is desirable to provide a photodetector that can suppress deterioration in quality.

[0006] A photodetector according to an embodiment of the present disclosure includes a first region having a plurality of first pixels, each including a first photoelectric conversion element provided in a semiconductor layer, and a first trench provided between adjacent first pixels in the semiconductor layer; and a second region surrounding the first region, having second trenches provided in the semiconductor layer in a first direction and a second direction intersecting the first direction. The pattern density of the second trenches is greater than the pattern density of the first trenches. An electronic device according to an embodiment of the present disclosure includes an optical system and a photodetector that receives light transmitted through the optical system. The photodetector includes a first region having a plurality of first pixels, each including a first photoelectric conversion element provided in the semiconductor layer, and a first trench provided between adjacent first pixels in the semiconductor layer; and a second region surrounding the first region, having second trenches provided in the semiconductor layer in the first direction and a second direction intersecting the first direction. The pattern density of the second trenches is greater than the pattern density of the first trenches.

[0007] FIG. 1 is a block diagram illustrating an example of a schematic configuration of an imaging device that is an example of a photodetector according to an embodiment of the present disclosure. FIG. 2 is a diagram illustrating an example of a planar configuration of an imaging device according to an embodiment of the present disclosure. FIG. 3 is a diagram illustrating an example of a planar configuration of an imaging device according to an embodiment of the present disclosure. FIG. 4 is a diagram illustrating an example of a circuit configuration of an effective pixel of an imaging device according to an embodiment of the present disclosure. FIG. 5A is a diagram illustrating an example of a circuit configuration of a cell of an imaging device according to an embodiment of the present disclosure. FIG. 5B is a diagram illustrating an example of a circuit configuration of a cell of an imaging device according to an embodiment of the present disclosure. FIG. 6 is a diagram illustrating an example of a cross-sectional configuration of an imaging device according to an embodiment of the present disclosure. FIG. 7 is a diagram illustrating an example of a planar configuration of an imaging device according to an embodiment of the present disclosure. FIG. 8 is a diagram illustrating an example of a configuration of a pixel unit of an imaging device according to a first modification of the present disclosure. FIG. 9 is a diagram illustrating an example of a configuration of a pixel unit of an imaging device according to a second modification of the present disclosure. FIG. 10 is a diagram illustrating another example of a configuration of a pixel unit of an imaging device according to the second modification of the present disclosure. FIG. 11 is a diagram illustrating another example of a configuration of a pixel unit of an imaging device according to the second modification of the present disclosure. Fig. 12 is a diagram for explaining an example configuration of a pixel unit of an imaging device according to Modification 3 of the present disclosure. Fig. 13 is a diagram for explaining an example configuration of a pixel unit of an imaging device according to Modification 4 of the present disclosure. Fig. 14 is a diagram for explaining an example configuration of an imaging device according to Modification 5 of the present disclosure. Fig. 15 is a block diagram showing an example configuration of an electronic device having an imaging device. Fig. 16 is a block diagram showing an example of a schematic configuration of a vehicle control system. Fig. 17 is an explanatory diagram showing an example of installation positions of an outside-vehicle information detection unit and an imaging unit. Fig. 18 is a diagram showing an example of a schematic configuration of an endoscopic surgery system. Fig. 19 is a block diagram showing an example of the functional configuration of a camera head and a CCU.

[0008] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings. The description will be made in the following order: 1. Embodiment 2. Modification 3. Application Example 4. Application Example

[0009] 1 is a block diagram showing an example of a schematic configuration of an imaging device that is an example of a photodetection device according to an embodiment of the present disclosure. The photodetection device is a device that can detect incident light. The imaging device 1 that is a photodetection device has a plurality of pixels P each having a photoelectric conversion unit (photoelectric conversion element), and is configured to photoelectrically convert incident light to generate a signal.

[0010] The imaging device 1 can generate a signal by receiving light that has passed through an optical system (not shown) including an optical lens. The imaging device 1 is configured, for example, using a semiconductor substrate (e.g., a silicon substrate) on which a plurality of pixels P are provided. The photoelectric conversion unit of each pixel P of the imaging device 1 is, for example, a photodiode (PD) that is configured to be able to photoelectrically convert light.

[0011] 1, the imaging device 1 has an area (pixel section 100) in which a plurality of pixels P are two-dimensionally arranged in a matrix. The pixel section 100 of the imaging device 1 can also be referred to as a pixel array in which a plurality of pixels P are arranged. The photoelectric conversion section of each pixel P can also be referred to as a photoelectric conversion area. As will be described later, effective pixels, light-shielded pixels, etc. are arranged in the pixel section 100.

[0012] The imaging device 1 captures incident light (image light) from a subject to be measured via an optical system including an optical lens. The imaging device 1 captures an image of the subject formed by the optical lens. The imaging device 1 can generate pixel signals by photoelectrically converting the received light (e.g., visible light, infrared light, etc.). The imaging device 1, which is a photodetector, is a device that can receive incident light and generate a signal, and can also be called a light-receiving device.

[0013] The imaging device 1 (photodetector) may be configured as an image sensor, for example. The imaging device 1 may be, for example, a complementary metal oxide semiconductor (CMOS) image sensor. The imaging device 1 may have a structure (a stacked structure) formed by stacking multiple semiconductor layers. The imaging device 1 may be used in various electronic devices, such as digital still cameras, video cameras, and mobile phones.

[0014] 1 , the imaging device 1 includes a pixel unit 100, a pixel control unit 111, a signal processing unit 112, a control unit 113, and a processing unit 114. The imaging device 1 is also provided with, for example, a plurality of control lines Lread and a plurality of signal lines VSL. The control lines Lread are signal lines capable of transmitting signals for controlling the pixels P, and are connected to the pixel control unit 111 and the pixels P of the pixel unit 100.

[0015] 1 , a plurality of control lines Lread are wired in the pixel unit 100 for each pixel row made up of a plurality of pixels P arranged in the horizontal direction (row direction). The control lines Lread are configured to transmit control signals for reading out signals from the pixels P. The control lines Lread can also be considered drive lines (pixel drive lines) that transmit signals for driving the pixels P.

[0016] The signal line VSL is a signal line capable of transmitting a signal from a pixel P, and is connected to the pixel P of the pixel unit 100 and the signal processing unit 112. In the pixel unit 100, for example, one or more signal lines VSL are wired for each pixel column made up of multiple pixels P lined up in the vertical direction (column direction). The signal line VSL is configured to be able to transmit a signal output from the pixel P. In the imaging device 1, multiple signal lines VSL may be provided for one pixel column. The imaging device 1 may have multiple signal lines VSL for each pixel column.

[0017] The pixel control unit 111 is configured to be able to control each pixel P of the pixel unit 100. The pixel control unit 111 is a control circuit and is configured by a plurality of circuits including, for example, a buffer, a shift register, an address decoder, etc. The pixel control unit 111 generates a signal for controlling the pixel P and outputs it to each pixel P of the pixel unit 100 via a control line Lread. The pixel control unit 111 is controlled by the control unit 113 and controls the pixels P of the pixel unit 100.

[0018] The pixel control unit 111 generates signals for controlling the pixels P, such as signals for controlling the transfer transistors, selection transistors, and reset transistors of the pixels P, and supplies these signals to each pixel P via a control line Lread. The pixel control unit 111 can control the reading of pixel signals from each pixel P. The pixel control unit 111 can also be referred to as a pixel driving unit configured to be able to drive each pixel P. The pixel control unit 111 and the control unit 113 can also be referred to collectively as a pixel control unit.

[0019] The signal processing unit 112 is configured to be able to perform signal processing of input pixel signals. The signal processing unit 112 is a signal processing circuit and includes, for example, a load circuit, an AD (Analog-Digital) conversion circuit, a horizontal selection switch, etc. The load circuit is, for example, configured by a current source capable of supplying current to the amplification transistor of the pixel P. The load circuit, together with the amplification transistor of the pixel P, forms, for example, a source follower circuit.

[0020] The signal processing unit 112 may have an amplifier circuit configured to amplify signals read out from the pixels P via the signal lines VSL. A load circuit, an amplifier circuit, an AD conversion circuit, etc. are provided for each of the multiple signal lines VSL, for example. A load circuit, an amplifier circuit, an AD conversion circuit, etc. may be provided for each pixel column of the pixel unit 100.

[0021] The signals output from each pixel P selected and scanned by the pixel control unit 111 are input to the signal processing unit 112 via signal lines VSL. The signal processing unit 112 can perform signal processing such as AD conversion of the signals from the pixel P and CDS (Correlated Double Sampling). The signals from each pixel P transmitted through each of the signal lines VSL are subjected to signal processing by the signal processing unit 112 and output to the processing unit 114.

[0022] The processing unit 114 is configured to be able to perform signal processing on the input signal. The processing unit 114 is a processing circuit, and is configured, for example, by a circuit that performs various types of signal processing on pixel signals. The processing unit 114 may include a processor and a memory. The processing unit 114 performs signal processing on pixel signals input from the signal processing unit 112 and outputs the processed pixel signals. The processing unit 114 can perform various types of signal processing, for example, noise reduction processing, gradation correction processing, etc.

[0023] The control unit 113 is configured to be able to control each unit of the imaging device 1. The control unit 113 receives externally provided clocks, data instructing the operation mode, etc., and can also output data such as internal information of the imaging device 1. The control unit 113 is a control circuit and has, for example, a timing generator configured to be able to generate various timing signals. The control unit 113 performs drive control of the pixel control unit 111, the signal processing unit 112, etc., based on the various timing signals (pulse signals, clock signals, etc.) generated by the timing generator.

[0024] The pixel unit 100, the pixel control unit 111, the signal processing unit 112, etc. described above may be provided on a single substrate. The pixel control unit 111, the signal processing unit 112, the control unit 113, the processing unit 114, etc. may be provided on a single semiconductor substrate, or may be provided separately on multiple semiconductor substrates. The imaging device 1 may have a stacked structure formed by stacking multiple substrates. Note that some or all of the signal processing unit 112, the control unit 113, and the processing unit 114 may be configured integrally.

[0025] 2 and 3 are diagrams illustrating an example of a planar configuration of an imaging device according to an embodiment. Fig. 3 shows an area surrounded by a dashed line L1 in the pixel unit 100 of the imaging device 1 shown in Fig. 2. The imaging device 1 has the pixel unit 100 and a terminal unit 120. In the example shown in Fig. 2, a plurality of terminal units 120 are provided around the pixel unit 100.

[0026] 2, the incident direction of light from the subject is defined as the Z-axis direction, the left-right direction on the paper surface perpendicular to the Z-axis direction is defined as the X-axis direction, and the up-down direction on the paper surface perpendicular to the Z-axis direction and the X-axis direction is defined as the Y-axis direction. In the following figures, directions may be expressed based on the direction of the arrow in FIG. 2. Although not shown, the pixel control unit 111, signal processing unit 112, control unit 113, processing unit 114, etc. described above may be provided in the peripheral region of the pixel unit 100.

[0027] The plurality of pixels P provided in the pixel section 100 include effective pixels P1 and light-shielding pixels P2. The pixel section 100 also has a cell P3. The effective pixel P1 is a pixel that receives light from a measurement target (subject). The light-shielding pixels P2 and P3 have, for example, a light-shielding member (light-shielding film) and are in a light-shielding state. The cell P3 is provided as a dummy pattern and can also be called a dummy pixel.

[0028] The terminal section 120 exchanges signals with the outside. The terminal section 120 includes terminals (pads) used for transmitting signals with the outside. The terminal section 120 is provided, for example, in an area outside the pixel section 100. As an example, as schematically shown in FIG. 2 , the terminal section 120 includes a plurality of pads (PADs) and is arranged in a peripheral area of ​​the pixel section 100.

[0029] The terminal unit 120 includes, for example, input / output pads for inputting and outputting signals, input pads for inputting signals from outside the imaging device 1, and output pads for outputting signals to outside the imaging device 1. The terminal unit 120 also includes a power supply pad and a GND pad, and can supply a power supply voltage and a GND voltage (ground voltage) input from outside to each circuit of the imaging device 1.

[0030] The pixel section 100 of the imaging device 1 has an area where a plurality of effective pixels P1 are provided (referred to as an effective pixel area 101) and an area where a plurality of light-shielding pixels P2 are provided (referred to as a light-shielding pixel area 102). The pixel section 100 also has an area where a plurality of cells P3 are provided (referred to as a dummy pattern area 103).

[0031] A plurality of effective pixels P1 are two-dimensionally arranged in the effective pixel region 101. For example, the effective pixels P1 are arranged so as to be aligned in the horizontal direction (X-axis direction) and the vertical direction (Y-axis direction) as shown in Fig. 3. Each effective pixel P1 may have, for example, a filter configured to selectively transmit light of a specific wavelength range from among incident light.

[0032] The effective pixels P1 in the effective pixel region 101 include, for example, pixels (R pixels) provided with filters that transmit light in the red (R) wavelength range, pixels (G pixels) provided with filters that transmit light in the green (G) wavelength range, and pixels (B pixels) provided with filters that transmit light in the blue (B) wavelength range. In the pixel section 100, a plurality of R pixels, a plurality of G pixels, and a plurality of B pixels are repeatedly arranged.

[0033] The R, G, and B pixels are arranged, for example, according to a Bayer array. The R, G, and B pixels can generate R, G, and B component pixel signals, respectively. The imaging device 1 can obtain RGB pixel signals. The number and arrangement of effective pixels P1 in the effective pixel area 101 can be set arbitrarily.

[0034] The filters provided in the effective pixels P1 are not limited to primary color (RGB) filters, but may be complementary color filters. A filter corresponding to W (white), i.e., a filter that transmits light of the entire wavelength range of incident light, may be provided. The filter may also be a filter that transmits infrared light. Furthermore, if necessary, some or all of the effective pixels P1 may not be provided with filters.

[0035] Light from a subject to be measured is incident on each effective pixel P1 in the effective pixel area 101. The effective pixels P1 receive the incident light and perform photoelectric conversion to generate pixel signals. The imaging device 1 can generate image data representing the subject image using the pixel signals obtained by photoelectric conversion in each effective pixel P1.

[0036] As shown in the example of FIG. 3 , trenches 71 are provided in the effective pixel region 101. The trenches 71 are provided between adjacent effective pixels P1 to separate the effective pixels P1. The trenches 71 have, for example, a full trench isolation (FTI) structure. In the example of FIG. 3 , the trenches 71 are formed in a lattice shape in a plan view and are arranged at the boundaries between adjacent effective pixels P1. It can also be said that the effective pixels P1 have a structure partitioned by the trenches 71.

[0037] The light-shielded pixel region 102 is provided around the effective pixel region 101. For example, as shown in Figures 2 and 3, the light-shielded pixel region 102 is provided so as to surround the effective pixel region 101. In the light-shielded pixel region 102, as an example, a plurality of light-shielded pixels P2 are two-dimensionally arranged in the X-axis direction and the Y-axis direction so as to surround the effective pixel region 101.

[0038] The light-shielded pixels P2 are pixels shielded from light by a light-shielding member and can output a pixel signal indicating a reference level. The light-shielded pixels P2 generate and output, for example, a pixel signal indicating a reference level relative to the pixel signal of the effective pixel P1. The pixel signal generated by the light-shielded pixels P2 can be considered a signal indicating a black level (or offset level). The light-shielded pixels P2 are OPB (Optical Black) pixels, and the light-shielded pixel region 102 can also be considered an OPB pixel region.

[0039] The processing unit 114 (see FIG. 1 ) of the imaging device 1 is configured to be able to correct pixel signals. The processing unit 114 is configured to correct pixel signals generated by the effective pixels P1 using pixel signals generated by the light-shielded pixels P2. For example, the processing unit 114 can generate pixel signals in which noise components (e.g., dark current components) have been reduced by performing subtraction processing on the pixel signals of the effective pixels P1 and the light-shielded pixels P2. Note that this correction processing may be performed by the signal processing unit 112.

[0040] 3, trenches 72 are provided in the light-shielded pixel region 102. The trenches 72 are provided between adjacent light-shielded pixels P2 to separate the light-shielded pixels P2. The trenches 72 have, for example, an FTI structure similar to the trenches 71. In the example shown in FIG. 3, the trenches 72 and 71 are formed continuously and integrally.

[0041] 3, the trenches 72 are arranged in a grid pattern on the XY plane. The trenches 72 are arranged in a grid pattern around the effective pixel region 101 and are disposed at the boundaries between adjacent light-shielded pixels P2. The light-shielded pixels P2 can also be said to have a structure partitioned by the trenches 72. The number and arrangement of the light-shielded pixels P2 in the light-shielded pixel region 102 can be set as desired.

[0042] The dummy pattern region 103 is provided around the light-shielding pixel region 102. For example, as shown in Figures 2 and 3, the dummy pattern region 103 is provided so as to surround the light-shielding pixel region 102. As an example, a plurality of cells P3 are two-dimensionally arranged in the dummy pattern region 103 so as to surround the light-shielding pixel region 102.

[0043] The cells P3 are areas that are shielded from light by a light-shielding member, and can also be called dummy pixels or dummy patterns. As an example, the plurality of cells P3 are arranged so as to be aligned in the X-axis direction and the Y-axis direction, as shown in Figure 3. The number and arrangement of the cells P3 in the dummy pattern area 103 are not limited to the example shown in the figure, and can be changed as appropriate.

[0044] 3, a trench 73 is provided in the dummy pattern region 103. The trench 73 is provided between adjacent cells P3 to separate the cells P3. The trench 73 has an FTI structure, similar to the trenches 71 and 72. In the example shown in FIG. 3, the trench 73 and the trench 72 are formed continuously and integrally.

[0045] 3 , the trenches 73 are provided in a lattice pattern on the XY plane. The trenches 73 are provided in a lattice pattern around the light-shielded pixel region 102 and are arranged at the boundaries between adjacent cells P3. The cells P3 are regions defined by the trenches 73, and can also be said to have a structure partitioned by the trenches 73.

[0046] The imaging device 1 may be configured so that the pattern density of the trenches differs in each region. For example, the imaging device 1 is configured so that the pattern density of the trenches 73 in the dummy pattern region 103 differs from the pattern density of the trenches 71 in the effective pixel region 101. As an example, as shown in FIG. 3 , the pattern density of the trenches 73 in the dummy pattern region 103 is greater than the pattern density of the trenches 71 in the effective pixel region 101. The arrangement period (pitch) of the trenches 73 is shorter (narrower) than the arrangement period of the trenches 71.

[0047] Furthermore, the imaging device 1 may be configured so that the pattern density of the trenches 73 in the dummy pattern region 103 is different from the pattern density of the trenches 72 in the light-shielding pixel region 102. For example, as shown in the example in Fig. 3, the pattern density of the trenches 73 in the dummy pattern region 103 is greater than the pattern density of the trenches 72 in the light-shielding pixel region 102. Note that in the imaging device 1, the trenches 71 and 72 may be arranged so that the pattern density and pitch of the trenches 71 are the same as the pattern density and pitch of the trenches 72.

[0048] 4 is a diagram showing an example of the circuit configuration of an effective pixel of an imaging device according to an embodiment. The effective pixel P1 has a photoelectric conversion unit 12 (photoelectric conversion element) and a readout circuit 20. The photoelectric conversion unit 12 is configured to receive light and generate a signal. The readout circuit 20 is configured to be able to output a signal based on charges photoelectrically converted. The readout circuit 20 can read out a pixel signal based on the charges photoelectrically converted by the photoelectric conversion unit 12.

[0049] The photoelectric conversion unit 12 is a light receiving unit (light receiving element) configured to be able to generate electric charges by photoelectric conversion. In the example shown in Fig. 4, the photoelectric conversion unit 12 is a photodiode (PD) that converts incident light into electric charges. The photoelectric conversion unit 12 can perform photoelectric conversion to generate electric charges according to the amount of received light.

[0050] The read circuit 20 includes, for example, a transistor TRG1, a floating diffusion FD, a transistor AMP1, a transistor SEL1, and a transistor RST1. The transistors TRG1, AMP1, SEL1, and RST1 are each a MOS transistor (MOSFET) having a gate, a source, and a drain terminal.

[0051] 4, the transistors TRG1, AMP1, SEL1, and RST1 are each configured as an NMOS transistor, while the transistor of the effective pixel P1 may be configured as a PMOS transistor.

[0052] The transistor TRG1 is a transfer transistor and is configured to be able to transfer charges photoelectrically converted in the photoelectric conversion unit 12 to the floating diffusion FD. The transistor TRG1 is controlled by a signal VTRG to electrically connect or disconnect the photoelectric conversion unit 12 and the floating diffusion FD. The transistor TRG1 can transfer charges photoelectrically converted and accumulated in the photoelectric conversion unit 12 to the floating diffusion FD.

[0053] The floating diffusion FD is an accumulation unit configured to be able to accumulate transferred charges. The floating diffusion FD can accumulate charges photoelectrically converted by the photoelectric conversion unit 12. The floating diffusion FD can also be considered a holding unit capable of holding the transferred charges. The floating diffusion FD accumulates the transferred charges and converts them into a voltage according to the capacitance of the floating diffusion FD.

[0054] The transistor AMP1 is configured to generate and output a signal based on the charge accumulated in the floating diffusion FD. The transistor AMP1 is an amplifying transistor and can generate and output a signal based on the charge converted by the photoelectric conversion unit 12.

[0055] The gate of the transistor AMP1 is electrically connected to the floating diffusion FD, and the voltage converted by the floating diffusion FD is input to the gate of the transistor AMP1. In the example shown in Figure 4, the drain of the transistor AMP1 is connected to a power supply line to which a power supply voltage VDD is supplied.

[0056] The source of the transistor AMP1 is connected to a signal line VSL via a transistor SEL1. The transistor AMP1 is configured to generate a signal based on the charge stored in the floating diffusion FD, i.e., a signal based on the voltage of the floating diffusion FD, and output the signal to the signal line VSL.

[0057] The transistor SEL1 is configured to be able to control the output of a pixel signal. The transistor SEL1 is electrically connected in series with the transistor AMP1, for example, as shown in the example of FIG. 4. The transistor SEL1 is controlled by a signal VSEL and is configured to be able to output a signal from the transistor AMP1 to a signal line VSL. The transistor SEL1 is a selection transistor and can control the output timing of the pixel signal.

[0058] The transistor SEL1 is configured to be able to output a signal based on the charge converted by the photoelectric conversion unit 12. The transistor SEL1 can output a pixel signal of the effective pixel P1 to a signal line VSL. The transistor SEL1 may be electrically connected in series between the transistor AMP1 and a power supply line to which a power supply voltage VDD is applied.

[0059] The transistor RST1 is configured to be able to reset the voltage of the floating diffusion FD. In the example shown in Fig. 4, the transistor RST1 is electrically connected to a power supply line to which a power supply voltage VDD is applied, and is configured to reset the charge of the effective pixel P1. The transistor RST1 is a reset transistor.

[0060] The transistor RST1 is controlled by a signal VRST to reset the charge accumulated in the floating diffusion FD and reset the voltage of the floating diffusion FD. In the example shown in Figure 4, the transistor RST1 electrically connects the power supply line and the floating diffusion FD and can discharge the charge accumulated in the floating diffusion FD. The transistor RST1 can also discharge the charge accumulated in the photoelectric conversion unit 12 via the transistor TRG1.

[0061] The pixel control unit 111 (see Figure 1) of the imaging device 1 supplies control signals to the gates of transistors TRG1, SEL1, RST1, etc. of each pixel P via the control line Lread described above, turning the transistors on (conducting state) or off (non-conducting state).

[0062] The plurality of control lines Lread for each pixel row of the imaging device 1 include, for example, a line that transmits a signal VTRG that controls the transistor TRG1, a line that transmits a signal VSEL that controls the transistor SEL1, a line that transmits a signal VRST that controls the transistor RST1, etc. The transistors TRG1, SEL1, RST1, etc. are on / off controlled by the pixel control unit 111.

[0063] The light-shielded pixel P2 has, for example, the same circuit configuration as the above-mentioned effective pixel P1. The pixel control unit 111 controls the readout circuits 20 of each effective pixel P1 and each light-shielded pixel P2 to output pixel signals from each effective pixel P1 and each light-shielded pixel P2 to the signal line VSL. The pixel control unit 111 can control the reading out of the pixel signals of each effective pixel P1 and each light-shielded pixel P2 to the signal line VSL.

[0064] 5A is a diagram showing an example of a circuit configuration of a cell of an imaging device according to an embodiment. Cell P3 has, for example, circuit elements similar to those of the above-described effective pixel P1 (or light-shielded pixel P2). As shown in FIG. 5A , cell P3 has, for example, a photoelectric conversion unit 12, a transistor TRG2, a transistor AMP2, a transistor SEL2, and a transistor RST2.

[0065] The transistor TRG2 of the cell P3 is a transfer transistor and corresponds to the transistor TRG1 of the effective pixel P1. The gate of the transistor TRG2 is electrically connected to a wiring to which a reference voltage (e.g., a ground voltage) is applied or a wiring to which a power supply voltage is applied. In the example shown in FIG. 5A, the gate of the transistor TRG2 is electrically connected to a wiring to which a voltage VSS (e.g., 0 V) ​​is applied.

[0066] The transistor AMP2 of the cell P3 is an amplification transistor and corresponds to the transistor AMP1 of the effective pixel P1. The transistor SEL2 of the cell P3 is a selection transistor and corresponds to the transistor SEL1 of the effective pixel P1. The gate of the transistor SEL2 is electrically connected to a wiring to which a reference voltage is applied or a wiring to which a power supply voltage is applied.

[0067] 5A, the gate of the transistor SEL2 is electrically connected to a wiring to which a voltage VSS is applied. Note that, as shown in FIG. 5A, one of the source and drain of the transistor SEL2 may be in an open state without being connected to a signal line.

[0068] The transistor RST2 of the cell P3 is a reset transistor and corresponds to the transistor RST1 of the effective pixel P1. The gate of the transistor RST2 is electrically connected to a wiring to which a reference voltage or a power supply voltage is applied. In the example shown in FIG. 5A , the gate of the transistor RST2 is electrically connected to a wiring to which a voltage VSS is applied.

[0069] 5B is a diagram showing another example of the circuit configuration of a cell of the imaging device according to the embodiment. Cell P3 may have the circuit configuration shown in FIG. 5B. In the example shown in FIG. 5B, the gate of transistor AMP2 and the gate of transistor SEL2 are each electrically connected to a wiring to which a power supply voltage VDD is applied.

[0070] Fig. 6 is a diagram illustrating an example of a cross-sectional configuration of an imaging device according to an embodiment. Fig. 7 is a diagram illustrating an example of a planar configuration of an imaging device according to an embodiment. As shown in Fig. 6, the imaging device 1 has, for example, a lens 30, a semiconductor layer 10, and a multilayer wiring layer 60. The imaging device 1 has a configuration in which the lens 30, the semiconductor layer 10, and the multilayer wiring layer 60 are stacked in the Z-axis direction. From the light incident side, a layer on which the lens 30 is provided, the semiconductor layer 10, and the multilayer wiring layer 60 are provided.

[0071] As shown in FIG. 6 , the semiconductor layer 10 has opposing surfaces 11S1 and 11S2. The surface 11S2 is the surface opposite to the surface 11S1. The surface 11S1 of the semiconductor layer 10 is a light-receiving surface (light incident surface). The surface 11S2 of the semiconductor layer 10 is an element formation surface on which elements such as transistors are formed. A gate electrode, a gate insulating film (e.g., a gate oxide film), etc. are provided on the surface 11S2 of the semiconductor layer 10.

[0072] The semiconductor layer 10 is composed of a semiconductor substrate, for example, a Si (silicon) substrate. The semiconductor layer 10 may be an SOI (silicon on insulator) substrate, a SiGe (silicon germanium) substrate, a SiC (silicon carbide) substrate, or the like. The semiconductor layer 10 may be composed of a III-V group compound semiconductor material, or may be formed using other semiconductor materials.

[0073] 6, a layer including a lens 30 is provided on the surface 11S1 side of the semiconductor layer 10. A multilayer wiring layer 60 is provided on the surface 11S2 side of the semiconductor layer 10. The lens 30 is provided on the side where light from the optical system is incident, and the multilayer wiring layer 60 is provided on the side opposite to the side where the light is incident. The imaging device 1 is a so-called backside illuminated imaging device.

[0074] In the semiconductor layer 10, a plurality of photoelectric conversion units 12 (photoelectric conversion elements) are provided along a surface 11S1 and a surface 11S2 of the semiconductor layer 10. For example, the plurality of photoelectric conversion units 12 are embedded in the semiconductor layer 10. The photoelectric conversion units 12 are provided between the surface 11S1 and the surface 11S2 of the semiconductor layer 10.

[0075] The lens 30 (lens unit) is a lens that focuses light and is an optical component also called an on-chip lens. The lens 30 is provided above the photoelectric conversion unit 12, for example, for each effective pixel P1 or for each set of multiple effective pixels P1. Light from a subject to be measured is incident on the lens 30 via an optical system such as an imaging lens. The lens 30 guides the incident light to the photoelectric conversion unit 12 side of the effective pixel P1.

[0076] The photoelectric conversion unit 12 of the effective pixel P1 photoelectrically converts light incident through the lens 30. The imaging device 1 may have a filter such as an RGB color filter. The filter is provided, for example, between the lens 30 and the photoelectric conversion unit 12. The photoelectric conversion unit 12 can also be referred to as a photoelectric conversion layer.

[0077] The multilayer wiring layer 60 is provided by being stacked on the semiconductor layer 10. The multilayer wiring layer 60 includes, for example, a conductor film and an insulating film, and has a plurality of wirings and vias (VIAs). The multilayer wiring layer 60 has a configuration in which a plurality of wirings are stacked via an insulating film serving as an interlayer insulating film (interlayer insulating layer). The multilayer wiring layer 60 includes, for example, two or more layers of wirings, or three or more layers of wirings.

[0078] The wiring of the multilayer wiring layer 60 is formed using a metal material such as aluminum (Al), copper (Cu), or tungsten (W). The wiring of the multilayer wiring layer 60 may be formed using polysilicon (Poly-Si) or other conductive materials. The interlayer insulating film is formed using, for example, silicon oxide (SiO), silicon nitride (SiN), silicon oxynitride (SiON), or the like.

[0079] For example, the above-mentioned transistors (transfer transistor, amplification transistor, selection transistor, reset transistor, etc.) are provided in the semiconductor layer 10 and the multilayer wiring layer 60. Furthermore, the above-mentioned pixel control unit 111, signal processing unit 112, control unit 113, processing unit 114, etc. (see FIG. 1 ) can be provided on a substrate separate from the semiconductor layer 10, or on the semiconductor layer 10 and the multilayer wiring layer 60.

[0080] 6 , the imaging device 1 has trenches 71, 72, and 73. The trenches 71, 72, and 73 are each an isolation portion (groove portion) and are made of, for example, an insulating material. The trench 71 is provided between adjacent photoelectric conversion portions 12 in the effective pixel region 101, and separates the photoelectric conversion portions 12. At least a portion of the trench 71 is provided at the boundary between adjacent effective pixels P1 (or photoelectric conversion portions 12).

[0081] The trenches 71 may be formed in the semiconductor layer 10 so as to surround the photoelectric conversion units 12 of each effective pixel P1. The trenches 71 may have, for example, an FTI structure and may be provided so as to penetrate the semiconductor layer 10. As in the example shown in FIG. 6 , the trenches 71 may be formed between adjacent photoelectric conversion units 12 so as to reach the surface 11S2 of the semiconductor layer 10.

[0082] The trenches 72 are provided between adjacent photoelectric conversion units 12 in the light-shielded pixel region 102, and separate the photoelectric conversion units 12. At least a portion of the trenches 72 is provided at the boundary between adjacent light-shielded pixels P2 (or photoelectric conversion units 12).

[0083] The trenches 72 may be formed in the semiconductor layer 10 so as to surround the photoelectric conversion units 12 of each light-shielded pixel P2. The trenches 72 may have, for example, an FTI structure and be provided so as to penetrate the semiconductor layer 10. The trenches 72 may be formed, for example, between adjacent photoelectric conversion units 12 so as to reach the surface 11S2 of the semiconductor layer 10.

[0084] The trenches 73 are provided in the dummy pattern region 103, for example, between adjacent photoelectric conversion units 12, and separate the photoelectric conversion units 12. At least a portion of the trenches 73 is provided at the boundary between adjacent cells P3 (or photoelectric conversion units 12).

[0085] The trenches 73 may be formed in the semiconductor layer 10 so as to surround the photoelectric conversion units 12 of each cell P3. The trenches 73 may have, for example, an FTI structure and be provided so as to penetrate the semiconductor layer 10. The trenches 73 may be formed, for example, between adjacent photoelectric conversion units 12 so as to reach the surface 11S2 of the semiconductor layer 10.

[0086] An insulating film, such as a silicon oxide film, a silicon nitride film, or an aluminum oxide film, is provided inside each of the trenches 71 to 73. Alternatively, the trenches 71 to 73 may be filled with polysilicon, a metal material, another insulating material, or the like. The trenches 71 to 73 may be configured with semiconductor regions (p-type semiconductor regions or n-type semiconductor regions) formed by ion implantation.

[0087] The trenches 71 to 73 may also be formed using other insulating materials with a low refractive index. The trenches 71 to 73 may also have voids (cavities). In the imaging device 1, the provision of the trenches 71 to 73 prevents the charge photoelectrically converted by the photoelectric conversion unit 12 from leaking to surrounding pixels. Furthermore, it is possible to prevent unnecessary light from leaking to surrounding pixels. For example, it is possible to prevent color mixing.

[0088] 6, the imaging device 1 is provided with a light-shielding member 40. The light-shielding member 40 is a light-shielding portion (light-shielding film) made of a material that blocks light, and is provided on the surface 11S1 side of the semiconductor layer 10. In the example shown in FIG. 6, the light-shielding member 40 is provided for the light-shielding pixel region 102 and the dummy pattern region 103, and is located on the surface 11S1 of the semiconductor layer 10.

[0089] The light-shielding member 40 is formed so as to cover the entire light-shielding pixel region 102 and the dummy pattern region 103. For example, the light-shielding member 40 is provided so as to cover all the light-shielding pixels P2 arranged in the light-shielding pixel region 102 and all the cells P3 arranged in the dummy pattern region 103.

[0090] The light-shielding member 40 is made of, for example, a metal material that blocks light (aluminum (Al), tungsten (W), copper (Cu), etc.). The light-shielding member 40 may be made of a material that absorbs light. The light-shielding member 40 may be made of a laminated film in which multiple films (for example, metal films such as copper and aluminum) are stacked.

[0091] The imaging device 1 may have at least one of a fixed charge film and an anti-reflection film on the surface 11S1 side of the semiconductor layer 10. The fixed charge film and the anti-reflection film are, for example, made of a metal compound (metal oxide, metal nitride, etc.) and can also be called a metal compound layer.

[0092] The fixed charge film is a film having a fixed charge and can be formed using a high dielectric material. For example, the fixed charge film is made of a metal oxide such as hafnium oxide or aluminum oxide. The fixed charge film is, for example, a film having a negative fixed charge.

[0093] In the imaging device 1, the fixed charge film is provided to suppress the generation of dark current at the interface of the semiconductor layer 10. The fixed charge film may be formed of another metal oxide film, or may be formed using a metal nitride film or a metal oxynitride film. A film having a positive fixed charge may be provided as the fixed charge film.

[0094] The anti-reflection film is made of, for example, a metal oxide such as hafnium oxide or tantalum oxide. The anti-reflection film is provided on the surface 11S1 side of the semiconductor layer 10 to reduce (suppress) reflection. The anti-reflection film is provided, for example, so as to be stacked with the fixed charge film. The anti-reflection film may be made of an insulating material such as silicon nitride (SiN), silicon oxide (SiO), or aluminum oxide (AlO), or may be made of other materials.

[0095] As described above, the imaging device 1 is configured so that the pattern density of the trenches 73 is different from the pattern density of the trenches 71. The pattern density of the trenches 73 in the dummy pattern region 103 is greater than the pattern density of the trenches 71 in the effective pixel region 101, as in the examples shown in Figures 3 and 7. This makes it possible to suppress manufacturing variations in the trenches in the imaging device 1.

[0096] If the trenches in the effective pixel region and the trenches in the dummy pattern region are provided with the same pattern density, there is a risk that the etching depth of the trenches in the effective pixel region and the dummy pattern region will differ significantly due to the influence of the position in the pixel section, the layout of the trenches, etc. In this case, trenches with the specified length (depth) will not be formed, and charge leakage may occur.

[0097] Generally, when etching a periodically (array-like) laid-out pattern into trenches, the etching depth tends to be shallower in trenches closer to the edges than in trenches closer to the center. This is because the local pattern density is lower near the edges than near the center, resulting in differences in the behavior of the plasma during the etching process. Therefore, the above-mentioned charge leakage is more likely to occur in the light-shielded pixel region than in the active pixel region.

[0098] In this embodiment, the pattern density of the trenches 73 in the dummy pattern region 103 is set to be greater than the pattern density of the trenches 71 in the effective pixel region 101. This makes it possible to suppress manufacturing variations in the trenches (for example, variations in the length of the trenches in the Z-axis direction). For example, it becomes possible to form trenches having an FTI structure with high precision by dry etching even near the end of the pixel section 100.

[0099] In the imaging device 1 according to the present embodiment, trenches having a predetermined length can be formed, making it possible to prevent charge leakage. This alleviates a local decrease in trench pattern density at the periphery of the effective pixel area 101, making it possible to prevent trench processing defects. This makes it possible to improve the yield of the imaging device 1.

[0100] In the imaging device 1, the arrangement period of the trenches 73 in the X-axis direction (or Y-axis direction) may be shorter (narrower) than the arrangement period of the trenches 71 in the X-axis direction (or Y-axis direction). Also, the arrangement period of the trenches 73 in the X-axis direction (or Y-axis direction) may be shorter than the arrangement period of the trenches 72 in the X-axis direction (or Y-axis direction).

[0101] 7 , for example, in the imaging device 1, the arrangement period d3 (pitch) of the trenches 73 is shorter than the arrangement period d1 of the trenches 71. The arrangement period d3 of the trenches 73 is also shorter than the arrangement period d2 of the trenches 72. This makes it possible to prevent the occurrence of defective trench processing in the light-shielded pixel region 102 and the dummy pattern region 103. This makes it possible to effectively prevent charge mixing between adjacent effective pixels P1 in the effective pixel region 101, between light-shielded pixels P2 in the light-shielded pixel region 102, or between the effective pixel P1 and the light-shielded pixel P2.

[0102] The imaging device 1 according to the present embodiment can suppress the inclusion of noise in pixel signals due to imperfect trench processing, thereby improving the quality of pixel signals, i.e., suppressing blooming defects.

[0103] [Functions and Effects] The photodetector according to this embodiment includes a first region (effective pixel region 101) having a plurality of first pixels (effective pixels P1), each including a first photoelectric conversion element (photoelectric conversion unit 12) provided in a semiconductor layer (semiconductor layer 10), and first trenches (trench 71) provided between adjacent first pixels in the semiconductor layer, and a second region (dummy pattern region 103) provided around the first region and having second trenches (trench 73) provided in the semiconductor layer in a first direction and a second direction intersecting the first direction. The pattern density of the second trenches is greater than the pattern density of the first trenches.

[0104] The photodetector (image capture device 1) according to this embodiment has an effective pixel region 101 in which trenches 71 are provided, and a dummy pattern region 103 in which trenches 73 are provided. The pattern density of trenches 73 is greater than the pattern density of trenches 71. This makes it possible to suppress trench processing defects. It is possible to realize a photodetector that can suppress quality degradation.

[0105] The photodetector according to this embodiment further includes a third region (light-shielded pixel region 102) provided between the first region and the second region. The third region includes a plurality of second pixels (light-shielded pixels P2) each including a second photoelectric conversion element provided in the semiconductor layer, a fourth trench (trench 72) provided between adjacent second pixels in the semiconductor layer, and a light-shielding member (light-shielding member 40) provided on the semiconductor layer. The pattern density of the second trenches is greater than the pattern density of the fourth trenches.

[0106] The photodetector (imaging device 1) according to this embodiment has a light-shielding pixel region 102 in which trenches 72 are provided. The pattern density of trenches 73 is greater than the pattern density of trenches 72. This makes it possible to suppress trench processing defects. It is possible to realize a photodetector that can suppress quality degradation.

[0107] Next, a modified example of the present disclosure will be described. In the following, the same components as those in the above embodiment will be denoted by the same reference numerals, and the description thereof will be omitted as appropriate.

[0108] 2. Modifications (2-1. Modification 1) In the above-described embodiment, an example configuration of the imaging device 1 has been described, but this is merely an example, and the configuration of the imaging device 1 is not limited to the above-described example. Fig. 8 is a diagram for explaining an example configuration of a pixel section of an imaging device according to Modification 1 of the present disclosure. The imaging device 1 may be configured so that the pattern density of the trenches 73 in the dummy pattern region 103 varies depending on the distance from the center of the pixel section 100 (or the distance from the effective pixel region 101).

[0109] The pattern density of the trenches 73 may increase with increasing distance from the effective pixel region 101 (or the light-shielding pixel region 102) in the dummy pattern region 103. As in the example shown in Figure 8, the arrangement period of the trenches 73 in the X-axis direction may decrease (become narrower) with increasing distance from the effective pixel region 101 (or the light-shielding pixel region 102).

[0110] Furthermore, the arrangement period of the trenches 73 in the Y-axis direction may become shorter as the distance from the effective pixel region 101 increases. In this modification, the pattern density of the trenches in the dummy pattern region 103 can be gradually changed. This reduces the difference in pattern density of the trenches between the effective pixel region 101 (or the light-shielding pixel region 102) and the dummy pattern region 103, making it possible to suppress the occurrence of defective trench processing.

[0111] (2-2. Modification 2) FIG. 9 is a diagram for explaining a configuration example of a pixel section of an imaging device according to Modification 2. The imaging device 1 may have a trench 74 as in the example shown in FIG. 9. The trench 74 is formed in the semiconductor layer 10 in a dummy pattern region 103. The trench 74 is provided, for example, adjacent to the trench 73 in the semiconductor layer 10. As in the example shown in FIG. 9, a plurality of trenches 74 may be provided discretely in the dummy pattern region 103. For example, the trench 74 may be provided for each cell P3.

[0112] The trench 74 has, for example, an FTI structure similar to the trench 73, and is provided so as to penetrate the semiconductor layer 10. As an example, the trench 74 may have a cross shape in a plan view. The trench 74 may have a line shape (linear) in a plan view, or may have another shape. The trench 74 can be used to correct (adjust) the pattern density of the trench, and can also be called a correction pattern.

[0113] In the imaging device 1 according to this modification, the trenches 74 enable fine adjustment of the pattern density of the trenches in the dummy pattern region 103. This effectively prevents the occurrence of trench processing defects. Note that the shape and arrangement of the trenches 74 are not limited to the example shown in the drawing and can be changed as appropriate.

[0114] 10 and 11 are diagrams illustrating another example of the configuration of the pixel section of the imaging device according to Modification 2. The imaging device 1 may be configured so that the pattern density of the trenches 74 varies in the dummy pattern region 103 depending on the distance from the center of the pixel section 100 (or the distance from the effective pixel region 101). Also, a plurality of trenches 74 having different shapes (trench 74a, trench 74b in FIG. 10) may be provided.

[0115] In the dummy pattern region 103 of the imaging device 1, the trenches 73 and the trenches 74 may be provided so that the pattern density of the trenches increases with increasing distance from the effective pixel region 101. For example, as shown in the example of FIG. 10 , a linear trench 74a may be arranged in a cell P3 that is relatively close to the light-shielded pixel region 102, and a cross-shaped trench 74b may be arranged in a cell P3 that is relatively far from the light-shielded pixel region 102.

[0116] In the imaging device 1, the number of trenches 74 may vary depending on the distance from the center of the pixel section 100 (or the distance from the effective pixel region 101). For example, as in the example shown in Fig. 11 , the imaging device 1 may be configured so that the number of cells P3 in which trenches 74 are provided increases with increasing distance from the effective pixel region 101 (or the light-shielded pixel region 102).

[0117] 10 or 11 , it is also possible to reduce the difference in trench pattern density (i.e., the step in pattern density) between the effective pixel region 101 (or the light-shielded pixel region 102) and the dummy pattern region 103. This makes it possible to prevent trench processing defects from occurring.

[0118] (2-3. Modification 3) Fig. 12 is a diagram illustrating an example of the configuration of a pixel section of an imaging device according to Modification 3. As in the example shown in Fig. 12, the size of the light-shielded pixel region 102 may be different above, below, left, and right of the effective pixel region 101. In the imaging device 1, a different number of light-shielded pixels P2 may be provided on the upper, lower, left, and right sides of the effective pixel region 101.

[0119] The size of the dummy pattern region 103 may be different above, below, left, and right of the effective pixel region 101. In the imaging device 1, different numbers of cells P3 may be arranged on the upper side, lower side, left side, and right side of the light-shielded pixel region 102.

[0120] (2-4. Modification 4) Fig. 13 is a diagram illustrating an example of the configuration of a pixel section of an imaging device according to Modification 4. As in the example schematically shown in Fig. 13, the width of trench 73 may be larger (wider) than the width of trench 71 (or trench 72). For example, the width of trench 73 in the X-axis direction may be larger than the width of trench 71 (or trench 72) in the X-axis direction.

[0121] Furthermore, the width of trench 73 in the Y-axis direction may be larger than the width of trench 71 (or trench 72) in the Y-axis direction. In this modified example, the same effects as those of the above-described embodiment can be obtained.

[0122] (2-5. Modification 5) FIG. 14 is a diagram illustrating an example of the configuration of an imaging device according to Modification 5. The trenches (trench 71 to trench 73, etc.) of the imaging device 1 may be formed to a depth between the surfaces 11S1 and 11S2 of the semiconductor layer 10. For example, as shown in FIG. 14, the trenches 71 to 73 may be provided from the surface 11S1 side of the semiconductor layer 10 to a depth between the surfaces 11S1 and 11S2 of the semiconductor layer 10. In the case of this modification, it is also possible to suppress variations in the processing depth of the trenches (for example, insufficient processing depth at the chip periphery).

[0123] 3. Application Examples The imaging device 1 and the like can be applied to any type of electronic device with an imaging function, for example, a camera system such as a digital still camera or a video camera, a mobile phone with an imaging function, etc. Fig. 15 shows a schematic configuration of an electronic device 1000.

[0124] The electronic device 1000 includes, for example, a lens group 1001, an imaging device 1, a DSP (Digital Signal Processor) circuit 1002, a frame memory 1003, a display unit 1004, a recording unit 1005, an operation unit 1006, and a power supply unit 1007, which are interconnected via a bus line 1008.

[0125] The lens group 1001 captures incident light (image light) from a subject and forms an image on the imaging surface of the imaging device 1. The imaging device 1 converts the amount of incident light formed on the imaging surface by the lens group 1001 into an electrical signal on a pixel-by-pixel basis and supplies the signal as a pixel signal to the DSP circuit 1002.

[0126] The DSP circuit 1002 is a signal processing circuit that processes signals supplied from the imaging device 1. The DSP circuit 1002 outputs image data obtained by processing the signals from the imaging device 1. The frame memory 1003 temporarily stores the image data processed by the DSP circuit 1002 on a frame-by-frame basis.

[0127] The display unit 1004 is composed of a panel-type display device such as a liquid crystal panel or an organic EL (Electro Luminescence) panel, and records image data of moving images or still images captured by the imaging device 1 on a recording medium such as a semiconductor memory or a hard disk.

[0128] The operation unit 1006, in response to a user's operation, outputs operation signals for various functions of the electronic device 1000. The power supply unit 1007 supplies various types of power to the DSP circuit 1002, frame memory 1003, display unit 1004, recording unit 1005, and operation unit 1006 as needed.

[0129] 4. Application Examples (Application Examples to Mobile Bodies) The technology according to the present disclosure (the present technology) can be applied to various products. For example, the technology according to the present disclosure may be realized as a device mounted on any type of mobile body, such as an automobile, an electric vehicle, a hybrid electric vehicle, a motorcycle, a bicycle, personal mobility, an airplane, a drone, a ship, or a robot.

[0130] FIG. 16 is a block diagram showing a schematic configuration example of a vehicle control system, which is an example of a mobile object control system to which the technology according to the present disclosure can be applied.

[0131] The vehicle control system 12000 includes a plurality of electronic control units connected via a communication network 12001. In the example shown in Fig. 16, the vehicle control system 12000 includes a drive system control unit 12010, a body system control unit 12020, an outside-vehicle information detection unit 12030, an inside-vehicle information detection unit 12040, and an integrated control unit 12050. Also shown as functional components of the integrated control unit 12050 are a microcomputer 12051, an audio / video output unit 12052, and an in-vehicle network I / F (interface) 12053.

[0132] The drivetrain control unit 12010 controls the operation of devices related to the drivetrain of the vehicle in accordance with various programs. For example, the drivetrain control unit 12010 functions as a control device for a drive force generating device for generating a drive force of the vehicle, such as an internal combustion engine or a drive motor, a drive force transmission mechanism for transmitting the drive force to the wheels, a steering mechanism for adjusting the steering angle of the vehicle, and a braking device for generating a braking force of the vehicle.

[0133] The body system control unit 12020 controls the operation of various devices equipped in the vehicle body according to various programs. For example, the body system control unit 12020 functions as a control device for a keyless entry system, a smart key system, a power window device, or various lamps such as headlamps, backup lamps, brake lamps, turn signals, and fog lamps. In this case, radio waves transmitted from a portable device that serves as a key or signals from various switches can be input to the body system control unit 12020. The body system control unit 12020 receives these radio waves or signals and controls the vehicle's door lock device, power window device, lamps, etc.

[0134] The outside-vehicle information detection unit 12030 detects information outside the vehicle equipped with the vehicle control system 12000. For example, an imaging unit 12031 is connected to the outside-vehicle information detection unit 12030. The outside-vehicle information detection unit 12030 causes the imaging unit 12031 to capture images outside the vehicle and receives the captured images. The outside-vehicle information detection unit 12030 may perform object detection processing or distance detection processing for people, cars, obstacles, signs, characters on the road surface, etc. based on the received images.

[0135] The imaging unit 12031 is an optical sensor that receives light and outputs an electrical signal corresponding to the amount of light received. The imaging unit 12031 can output the electrical signal as an image or as distance measurement information. The light received by the imaging unit 12031 may be visible light or invisible light such as infrared light.

[0136] The in-vehicle information detection unit 12040 detects information inside the vehicle. For example, a driver state detection unit 12041 that detects the state of the driver is connected to the in-vehicle information detection unit 12040. The driver state detection unit 12041 includes, for example, a camera that captures an image of the driver, and the in-vehicle information detection unit 12040 may calculate the degree of fatigue or concentration of the driver based on the detection information input from the driver state detection unit 12041, or may determine whether the driver is dozing off.

[0137] The microcomputer 12051 can calculate control target values ​​for the driving force generating device, steering mechanism, or braking device based on the information inside and outside the vehicle acquired by the outside-vehicle information detection unit 12030 or the inside-vehicle information detection unit 12040, and output control commands to the drive system control unit 12010. For example, the microcomputer 12051 can perform cooperative control aimed at realizing the functions of an ADAS (Advanced Driver Assistance System), including vehicle collision avoidance or impact mitigation, following driving based on the inter-vehicle distance, vehicle speed maintenance driving, vehicle collision warning, vehicle lane departure warning, etc.

[0138] In addition, the microcomputer 12051 can perform cooperative control for the purpose of autonomous driving, which allows the vehicle to travel autonomously without relying on driver operation, by controlling the driving force generating device, steering mechanism, braking device, etc. based on information about the surroundings of the vehicle obtained by the outside vehicle information detection unit 12030 or the inside vehicle information detection unit 12040.

[0139] Furthermore, the microcomputer 12051 can output a control command to the body system control unit 12020 based on the information outside the vehicle acquired by the outside information detection unit 12030. For example, the microcomputer 12051 can control the headlamps according to the position of a preceding vehicle or an oncoming vehicle detected by the outside information detection unit 12030, and perform cooperative control aimed at preventing glare, such as switching from high beams to low beams.

[0140] The audio / video output unit 12052 transmits at least one of audio and video output signals to an output device capable of visually or audibly notifying information to vehicle occupants or the outside of the vehicle. In the example of Fig. 16, the output devices are exemplified by an audio speaker 12061, a display unit 12062, and an instrument panel 12063. The display unit 12062 may include, for example, at least one of an on-board display and a head-up display.

[0141] FIG. 17 is a diagram showing an example of the installation position of the imaging unit 12031.

[0142] In FIG. 17, a vehicle 12100 has imaging units 12101, 12102, 12103, 12104, and 12105 as the imaging unit 12031.

[0143] The imaging units 12101, 12102, 12103, 12104, and 12105 are provided, for example, at positions such as the front nose, side mirrors, rear bumper, back door, and the top of the windshield inside the vehicle cabin of the vehicle 12100. The imaging unit 12101 provided on the front nose and the imaging unit 12105 provided on the top of the windshield inside the vehicle cabin mainly acquire images of the front of the vehicle 12100. The imaging units 12102 and 12103 provided on the side mirrors mainly acquire images of the sides of the vehicle 12100. The imaging unit 12104 provided on the rear bumper or back door mainly acquires images of the rear of the vehicle 12100. The forward images acquired by the imaging units 12101 and 12105 are mainly used to detect preceding vehicles, pedestrians, obstacles, traffic lights, traffic signs, lanes, etc.

[0144] 17 shows an example of the imaging ranges of the imaging units 12101 to 12104. Imaging range 12111 indicates the imaging range of the imaging unit 12101 provided on the front nose, imaging ranges 12112 and 12113 indicate the imaging ranges of the imaging units 12102 and 12103 provided on the side mirrors, respectively, and imaging range 12114 indicates the imaging range of the imaging unit 12104 provided on the rear bumper or back door. For example, by overlaying the image data captured by the imaging units 12101 to 12104, an overhead image of the vehicle 12100 viewed from above can be obtained.

[0145] At least one of the image capturing units 12101 to 12104 may have a function of acquiring distance information. For example, at least one of the image capturing units 12101 to 12104 may be a stereo camera made up of multiple image capturing elements, or may be an image capturing element having pixels for phase difference detection.

[0146] For example, based on the distance information obtained from the imaging units 12101 to 12104, the microcomputer 12051 can calculate the distance to each three-dimensional object within the imaging ranges 12111 to 12114 and the change in this distance over time (relative speed with respect to the vehicle 12100), thereby extracting as a preceding vehicle, in particular, the three-dimensional object that is the closest three-dimensional object on the path of the vehicle 12100 and traveling in approximately the same direction as the vehicle 12100 at a predetermined speed (e.g., 0 km / h or higher). Furthermore, the microcomputer 12051 can set a vehicle-to-vehicle distance to be maintained in advance in front of the preceding vehicle, and perform automatic braking control (including follow-up stop control), automatic acceleration control (including follow-up start control), etc. In this way, cooperative control can be performed for the purpose of autonomous driving, which runs autonomously without relying on driver operation.

[0147] For example, the microcomputer 12051 classifies and extracts three-dimensional object data regarding three-dimensional objects into two-wheeled vehicles, ordinary vehicles, large vehicles, pedestrians, utility poles, and other three-dimensional objects based on distance information obtained from the imaging units 12101 to 12104, and can use the data for automatic obstacle avoidance. For example, the microcomputer 12051 distinguishes obstacles around the vehicle 12100 into obstacles that are visible to the driver of the vehicle 12100 and obstacles that are difficult to see. The microcomputer 12051 then determines a collision risk that indicates the risk of collision with each obstacle, and when the collision risk is equal to or greater than a set value and a collision is possible, the microcomputer 12051 can provide driving assistance for collision avoidance by outputting an alarm to the driver via the audio speaker 12061 or the display unit 12062, or by performing forced deceleration or avoidance steering via the drive system control unit 12010.

[0148] At least one of the image capturing units 12101 to 12104 may be an infrared camera that detects infrared rays. For example, the microcomputer 12051 can recognize a pedestrian by determining whether a pedestrian is present in the images captured by the image capturing units 12101 to 12104. Such pedestrian recognition is performed, for example, by extracting feature points from the images captured by the image capturing units 12101 to 12104 as infrared cameras and performing pattern matching on a series of feature points that indicate the outline of an object to determine whether the object is a pedestrian. When the microcomputer 12051 determines that a pedestrian is present in the images captured by the image capturing units 12101 to 12104 and recognizes the pedestrian, the audio / image output unit 12052 controls the display unit 12062 to superimpose a rectangular outline on the recognized pedestrian for emphasis. The audio / image output unit 12052 may also control the display unit 12062 to display an icon or the like indicating the pedestrian at a desired position.

[0149] An example of a mobile object control system to which the technology according to the present disclosure can be applied has been described above. The technology according to the present disclosure can be applied to, for example, the image capturing unit 12031 of the above-described configuration. Specifically, for example, the image capturing device 1 or the like can be applied to the image capturing unit 12031. By applying the technology according to the present disclosure to the image capturing unit 12031, it becomes possible to obtain high-resolution captured images. It becomes possible to perform high-precision control using captured images in the mobile object control system.

[0150] (Application Example to Endoscopic Surgery System) The technology according to the present disclosure (the present technology) can be applied to various products. For example, the technology according to the present disclosure may be applied to an endoscopic surgery system.

[0151] FIG. 18 is a diagram showing an example of a schematic configuration of an endoscopic surgery system to which the technology according to the present disclosure (the present technology) can be applied.

[0152] 18 shows an operator (doctor) 11131 performing surgery on a patient 11132 on a patient bed 11133 using an endoscopic surgery system 11000. As shown in the figure, the endoscopic surgery system 11000 is composed of an endoscope 11100, other surgical tools 11110 such as an insufflation tube 11111 and an energy treatment tool 11112, a support arm device 11120 that supports the endoscope 11100, and a cart 11200 on which various devices for endoscopic surgery are mounted.

[0153] The endoscope 11100 is composed of a lens barrel 11101, a region of a predetermined length from the tip of which is inserted into a body cavity of a patient 11132, and a camera head 11102 connected to the base end of the lens barrel 11101. In the example shown, the endoscope 11100 is configured as a so-called rigid scope having a rigid lens barrel 11101, but the endoscope 11100 may also be configured as a so-called flexible scope having a flexible lens barrel.

[0154] An opening into which an objective lens is fitted is provided at the tip of the lens barrel 11101. A light source device 11203 is connected to the endoscope 11100, and light generated by the light source device 11203 is guided to the tip of the lens barrel by a light guide extending inside the lens barrel 11101, and is irradiated via the objective lens toward an object to be observed inside the body cavity of the patient 11132. The endoscope 11100 may be a direct-viewing endoscope, an oblique-viewing endoscope, or a side-viewing endoscope.

[0155] An optical system and an image sensor are provided inside the camera head 11102, and light reflected from the object of observation (observation light) is collected by the optical system onto the image sensor. The observation light is photoelectrically converted by the image sensor to generate an electrical signal corresponding to the observation light, i.e., an image signal corresponding to the observed image. The image signal is sent to a camera control unit (CCU) 11201 as RAW data.

[0156] The CCU 11201 is configured with a CPU (Central Processing Unit), a GPU (Graphics Processing Unit), etc., and comprehensively controls the operations of the endoscope 11100 and the display device 11202. Furthermore, the CCU 11201 receives an image signal from the camera head 11102 and performs various types of image processing on the image signal, such as development processing (demosaic processing), to display an image based on the image signal.

[0157] Under the control of the CCU 11201, the display device 11202 displays an image based on an image signal that has been subjected to image processing by the CCU 11201.

[0158] The light source device 11203 is composed of a light source such as an LED (Light Emitting Diode), and supplies the endoscope 11100 with irradiation light when photographing the surgical site, etc.

[0159] The input device 11204 is an input interface for the endoscopic surgery system 11000. A user can input various information and instructions to the endoscopic surgery system 11000 via the input device 11204. For example, the user inputs an instruction to change the imaging conditions (type of irradiation light, magnification, focal length, etc.) of the endoscope 11100.

[0160] The treatment tool control device 11205 controls the driving of the energy treatment tool 11112 for cauterizing tissue, incising, sealing blood vessels, etc. The insufflation device 11206 inflates the body cavity of the patient 11132 through the insufflation tube 11111 in order to ensure a clear field of view for the endoscope 11100 and a working space for the surgeon. The recorder 11207 is a device capable of recording various types of information related to the surgery. The printer 11208 is a device capable of printing various types of information related to the surgery in various formats such as text, images, or graphs.

[0161] The light source device 11203, which supplies illumination light to the endoscope 11100 when photographing the surgical site, can be configured from a white light source, such as an LED, a laser light source, or a combination of these. When the white light source is configured from a combination of RGB laser light sources, the output intensity and output timing of each color (each wavelength) can be controlled with high precision, allowing the light source device 11203 to adjust the white balance of the captured image. In this case, it is also possible to time-share images corresponding to each RGB by irradiating the object of observation with laser light from each RGB laser light source and controlling the drive of the image sensor of the camera head 11102 in synchronization with the irradiation timing. According to this method, color images can be obtained without providing a color filter to the image sensor.

[0162] Furthermore, the light source device 11203 may be controlled to change the intensity of light it outputs at predetermined time intervals. By controlling the driving of the image sensor of the camera head 11102 in synchronization with the timing of the change in light intensity to acquire images in a time-division manner and combining the images, it is possible to generate an image with a high dynamic range that is free from so-called blocked-up shadows and blown-out highlights.

[0163] The light source device 11203 may also be configured to supply light in a predetermined wavelength band corresponding to special light observation. Special light observation, for example, utilizes the wavelength dependence of light absorption in body tissues to irradiate light in a narrower band than the light irradiated during normal observation (i.e., white light) to capture high-contrast images of specific tissues, such as blood vessels on the surface of mucous membranes, in what is known as narrow band imaging. Alternatively, special light observation may involve fluorescence observation, in which images are obtained using fluorescence generated by irradiating excitation light. Fluorescence observation may involve irradiating excitation light onto body tissues and observing the fluorescence from the tissues (autofluorescence observation), or may involve locally injecting a reagent such as indocyanine green (ICG) into the body tissue and irradiating the tissues with excitation light corresponding to the fluorescent wavelength of the reagent to obtain a fluorescent image. The light source device 11203 may be configured to supply narrow band light and / or excitation light corresponding to such special light observation.

[0164] FIG. 19 is a block diagram showing an example of the functional configuration of the camera head 11102 and the CCU 11201 shown in FIG.

[0165] The camera head 11102 has a lens unit 11401, an imaging unit 11402, a drive unit 11403, a communication unit 11404, and a camera head control unit 11405. The CCU 11201 has a communication unit 11411, an image processing unit 11412, and a control unit 11413. The camera head 11102 and the CCU 11201 are connected to each other via a transmission cable 11400 so that they can communicate with each other.

[0166] The lens unit 11401 is an optical system provided at the connection portion with the lens barrel 11101. Observation light taken in from the tip of the lens barrel 11101 is guided to the camera head 11102 and enters the lens unit 11401. The lens unit 11401 is composed of a combination of multiple lenses including a zoom lens and a focus lens.

[0167] The imaging unit 11402 is composed of an imaging element. The imaging element constituting the imaging unit 11402 may be a single (so-called single-chip type) or multiple (so-called multi-chip type). When the imaging unit 11402 is composed of a multi-chip type, for example, each imaging element may generate an image signal corresponding to each of RGB, and a color image may be obtained by combining these signals. Alternatively, the imaging unit 11402 may be configured to have a pair of imaging elements for acquiring image signals for the right eye and the left eye corresponding to 3D (dimensional) display. The 3D display allows the surgeon 11131 to more accurately grasp the depth of the biological tissue at the surgical site. Note that when the imaging unit 11402 is composed of a multi-chip type, multiple lens units 11401 may be provided corresponding to each imaging element.

[0168] Furthermore, the imaging unit 11402 does not necessarily have to be provided in the camera head 11102. For example, the imaging unit 11402 may be provided inside the lens barrel 11101, immediately after the objective lens.

[0169] The driving unit 11403 is configured by an actuator, and moves the zoom lens and focus lens of the lens unit 11401 by a predetermined distance along the optical axis under the control of the camera head control unit 11405. This allows the magnification and focus of the image captured by the imaging unit 11402 to be adjusted appropriately.

[0170] The communication unit 11404 is configured by a communication device for transmitting and receiving various types of information to and from the CCU 11201. The communication unit 11404 transmits the image signal obtained from the imaging unit 11402 to the CCU 11201 via the transmission cable 11400 as RAW data.

[0171] Furthermore, 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. The control signal includes information on the imaging conditions, such as information specifying the frame rate of the captured image, information specifying the exposure value at the time of imaging, and / or information specifying the magnification and focus of the captured image.

[0172] The image capturing conditions such as the frame rate, exposure value, magnification, and focus may be appropriately specified by the user, or may be automatically set by the control unit 11413 of the CCU 11201 based on the acquired image signal. In the latter case, the endoscope 11100 is equipped with a so-called AE (Auto Exposure) function, AF (Auto Focus) function, and AWB (Auto White Balance) function.

[0173] The camera head control unit 11405 controls the driving of the camera head 11102 based on a control signal received from the CCU 11201 via the communication unit 11404 .

[0174] The communication unit 11411 is configured by a communication device for transmitting and receiving various information to and from the camera head 11102. The communication unit 11411 receives an image signal transmitted from the camera head 11102 via the transmission cable 11400.

[0175] Furthermore, the communication unit 11411 transmits to the camera head 11102 a control signal for controlling the driving of the camera head 11102. The image signal and the control signal can be transmitted by electrical communication, optical communication, or the like.

[0176] The image processing unit 11412 performs various image processing operations on the image signal, which is RAW data transmitted from the camera head 11102 .

[0177] The control unit 11413 performs various controls related to the imaging of the surgical site, etc. by the endoscope 11100 and the display of the captured image obtained by imaging the surgical site, etc. For example, the control unit 11413 generates a control signal for controlling the driving of the camera head 11102.

[0178] Furthermore, the control unit 11413 displays the captured image showing the surgical site, etc., on the display device 11202 based on the image signal subjected to image processing by the image processing unit 11412. At this time, the control unit 11413 may recognize various objects in the captured image using various image recognition technologies. For example, the control unit 11413 can recognize surgical tools such as forceps, specific biological parts, bleeding, mist generated when using the energy treatment tool 11112, etc., by detecting the shape and color of the edges of objects included in the captured image. When displaying the captured image on the display device 11202, the control unit 11413 may use the recognition results to superimpose various surgical support information on the image of the surgical site. By superimposing the surgical support information and presenting it to the surgeon 11131, the burden on the surgeon 11131 can be reduced and the surgeon 11131 can proceed with the surgery reliably.

[0179] The transmission cable 11400 connecting the camera head 11102 and the CCU 11201 is an electrical signal cable for electrical signal communication, an optical fiber for optical communication, or a composite cable of these.

[0180] In the illustrated example, communication is performed wired using a transmission cable 11400, but communication between the camera head 11102 and the CCU 11201 may also be performed wirelessly.

[0181] The above describes an example of an endoscopic surgery system to which the technology according to the present disclosure can be applied. Of the above-described configurations, the technology according to the present disclosure can be suitably applied to, for example, the imaging unit 11402 provided in the camera head 11102 of the endoscope 11100. By applying the technology according to the present disclosure to the imaging unit 11402, it is possible to provide a high-definition endoscope 11100.

[0182] The present disclosure has been described above by way of embodiments, modifications, application examples, and applied examples, but the present technology is not limited to the above embodiments, etc., and various modifications are possible. For example, although the above-mentioned modifications have been described as modifications of the above embodiments, the configurations of the modifications can be combined as appropriate. For example, the present disclosure is not limited to back-illuminated image sensors, but can also be applied to front-illuminated image sensors.

[0183] In the above embodiments, an imaging device has been described as an example, but the photodetector of the present disclosure may be, for example, a device that receives incident light and converts the light into an electric charge. The output signal may be a signal of image information or a signal of ranging information. The photodetector (imaging device) may be applied to an image sensor, a ranging sensor, etc.

[0184] According to one embodiment of the present disclosure, a photodetector device includes a first region having a plurality of first pixels each including a first photoelectric conversion element provided in a semiconductor layer and a first trench provided between adjacent first pixels in the semiconductor layer; and a second region having second trenches provided in the semiconductor layer in a first direction and a second direction intersecting the first direction and provided around the first region. The pattern density of the second trenches is greater than the pattern density of the first trenches. This makes it possible to suppress trench processing defects. This makes it possible to realize a photodetector device that can suppress quality degradation.

[0185] A photodetector according to one embodiment of the present disclosure includes a first region having a plurality of first pixels each including a first photoelectric conversion element provided in a semiconductor layer and a first trench provided between adjacent first pixels in the semiconductor layer, and a second region having second trenches provided in the semiconductor layer in a first direction and a second direction intersecting the first direction and provided around the first region. The second trenches are provided at a higher density than the first trenches in a plan view. This makes it possible to suppress trench processing defects. This makes it possible to realize a photodetector capable of suppressing quality degradation.

[0186] Note that the effects described in this specification are merely examples and are not limited to those described above, and other effects may be present. The present disclosure may also have the following configurations: (1) A photodetector including: a first region having a plurality of first pixels, each including a first photoelectric conversion element provided in a semiconductor layer, and a first trench provided between adjacent first pixels in the semiconductor layer; and a second region having second trenches provided in the semiconductor layer in a first direction and a second direction intersecting the first direction, the second region being provided around the first region, wherein the pattern density of the second trenches is greater than the pattern density of the first trenches. (2) The photodetector described in (1) above further includes a light-shielding member provided on the semiconductor layer in the second region. (3) The photodetector described in (1) or (2) above, wherein the first trench and the second trench are provided so as to be continuous in a plan view. (4) The photodetector according to any one of (1) to (3), wherein the arrangement period of the second trenches in the first direction is shorter than the arrangement period of the first trenches in the first direction. (5) The photodetector according to any one of (1) to (4), wherein the pattern density of the second trenches increases in the second region with increasing distance from the first region. (6) The photodetector according to any one of (1) to (5), wherein the arrangement period of the second trenches in the first direction decreases with increasing distance from the first region. (7) The photodetector according to any one of (1) to (6), wherein the second region includes third trenches provided adjacent to the second trenches in the semiconductor layer. (8) The photodetector according to (7), wherein a plurality of the third trenches are provided discretely in the second region in a plan view. (9) The photodetector according to (7) or (8), wherein the pattern density of the third trenches increases in the second region with increasing distance from the first region.(10) The photodetector according to any one of (7) to (8), wherein the second region has cells surrounded by the second trenches and in which the third trenches are provided, and the number of the cells in which the third trenches are provided increases with increasing distance from the first region. (11) The photodetector according to any one of (1) to (10), wherein the width of the second trench in the first direction is greater than the width of the first trench in the first direction. (12) The photodetector according to any one of (1) to (11), wherein the second region is provided so as to surround the first region. (13) The photodetector according to any one of (1) to (12), wherein the first pixel has the first photoelectric conversion element and a first transistor, the second region has a cell surrounded by the second trench and provided with a second transistor, a gate of the first transistor is connected to a wiring to which a first signal is input, and a gate of the second transistor is connected to a wiring to which a power supply voltage is applied or a wiring to which a reference voltage is applied. (14) The photodetector according to (13), wherein the first signal is a signal for controlling the first transistor, and the first transistor is a transistor capable of transferring charge photoelectrically converted by the first photoelectric conversion element. (15) The photodetector according to any one of (1) to (14), wherein the first trench is provided so as to penetrate the semiconductor layer. (16) The photodetector according to any one of (1) to (15), further comprising a third region provided between the first region and the second region, the third region having: a plurality of second pixels each including a second photoelectric conversion element provided in the semiconductor layer, a fourth trench provided between the plurality of second pixels adjacent to each other in the semiconductor layer, and a light-shielding member provided on the semiconductor layer. (17) The photodetector according to (16), wherein a pattern density of the second trench is higher than a pattern density of the fourth trench. (18) The photodetector according to (16) or (17), wherein the first trench and the fourth trench are provided so as to be continuous in a plan view.(19) The photodetector according to any one of (16) to (19), wherein an arrangement period of the second trenches in the first direction is shorter than an arrangement period of the fourth trenches in the first direction. (20) An electronic device comprising: an optical system; and a photodetector that receives light that has passed through the optical system, wherein the photodetector has: a first region having a plurality of first pixels each including a first photoelectric conversion element provided in a semiconductor layer and a first trench provided between the plurality of first pixels adjacent to each other in the semiconductor layer; and a second region having second trenches provided in the semiconductor layer in the first direction and a second direction intersecting the first direction, the second trenches being provided around the first region, wherein a pattern density of the second trenches is greater than a pattern density of the first trenches. (21) A photodetector comprising: a first region having a plurality of first pixels, each including a first photoelectric conversion element provided in a semiconductor layer, and first trenches provided between adjacent plurality of first pixels in the semiconductor layer; and a second region having second trenches provided in the semiconductor layer in a first direction and a second direction intersecting the first direction, the second region being provided around the first region, wherein a pattern density of the second trenches is greater than a pattern density of the first trenches in a planar view. (22) A photodetector comprising: a first region having a plurality of first pixels, each including a first photoelectric conversion element provided in a semiconductor layer, and first trenches provided between adjacent plurality of first pixels in the semiconductor layer, and a second region having second trenches provided in the semiconductor layer in the first direction and a second direction intersecting the first direction, the second trenches being provided around the first region, wherein the second trenches are provided at a higher density than the first trenches in a planar view.

[0187] This application claims priority based on Japanese Patent Application No. 2023-151094, filed on September 19, 2023, in the Japan Patent Office, the entire contents of which are incorporated herein by reference.

[0188] Those skilled in the art will recognize that various modifications, combinations, subcombinations, and variations may occur depending on design requirements and other factors, and are intended to be within the scope of the appended claims and their equivalents.

Claims

1. A photodetector comprising: a first region having a plurality of first pixels, each including a first photoelectric conversion element provided in a semiconductor layer, and a first trench provided between adjacent first pixels in the semiconductor layer; and a second region having second trenches provided in the semiconductor layer in a first direction and a second direction intersecting the first direction, the second region being provided around the first region, wherein a pattern density of the second trenches is greater than a pattern density of the first trenches.

2. The photodetector according to claim 1, further comprising a light-shielding member provided on said semiconductor layer in said second region.

3. The photodetector according to claim 1, wherein the first trench and the second trench are provided so as to be continuous in a plan view.

4. The photodetector according to claim 1, wherein the arrangement period of the second trenches in the first direction is shorter than the arrangement period of the first trenches in the first direction.

5. The photodetector according to claim 1, wherein the pattern density of the second trenches increases in the second region with increasing distance from the first region.

6. The photodetector according to claim 1, wherein the arrangement period of the second trenches in the first direction becomes shorter with increasing distance from the first region.

7. The photodetector according to claim 1, wherein the second region has a third trench provided adjacent to the second trench in the semiconductor layer.

8. The photodetector according to claim 7, wherein a plurality of the third trenches are provided discretely in the second region in a plan view.

9. The photodetector according to claim 7, wherein the pattern density of the third trenches increases in the second region with increasing distance from the first region.

10. The photodetector device according to claim 7, wherein the second region has cells surrounded by the second trench and in which the third trench is provided, and the number of cells in which the third trench is provided increases with increasing distance from the first region.

11. The photodetection device of claim 1, wherein the width of the second trench in the first direction is greater than the width of the first trench in the first direction.

12. The light detection device according to claim 1, wherein the second region is provided so as to surround the first region.

13. The photodetection device of claim 1, wherein the first pixel has the first photoelectric conversion element and a first transistor, the second region has a cell surrounded by the second trench and in which a second transistor is provided, the gate of the first transistor is connected to a wiring to which a first signal is input, and the gate of the second transistor is connected to a wiring to which a power supply voltage is applied or to a wiring to which a reference voltage is applied.

14. The photodetection device according to claim 13, wherein the first signal is a signal for controlling the first transistor, and the first transistor is a transistor capable of transferring charges photoelectrically converted by the first photoelectric conversion element.

15. The photodetector device according to claim 1, wherein the first trench is provided so as to penetrate through the semiconductor layer.

16. The photodetection device of claim 1, further comprising a third region provided between the first region and the second region, the third region having: a plurality of second pixels each including a second photoelectric conversion element provided in the semiconductor layer; a fourth trench provided between adjacent plurality of the second pixels in the semiconductor layer; and a light-shielding member provided on the semiconductor layer.

17. The photodetection device according to claim 16, wherein the pattern density of the second trench is greater than the pattern density of the fourth trench.

18. The light detection device according to claim 16, wherein the first trench and the fourth trench are provided so as to be continuous in a plan view.

19. The photodetector according to claim 16, wherein the arrangement period of the second trenches in the first direction is shorter than the arrangement period of the fourth trenches in the first direction.

20. An electronic device comprising: an optical system; and a photodetector that receives light transmitted through the optical system, wherein the photodetector has a first region having a plurality of first pixels, each including a first photoelectric conversion element provided in a semiconductor layer, and a first trench provided between adjacent plurality of the first pixels in the semiconductor layer; and a second region having a second trench provided in the semiconductor layer in a first direction and a second direction intersecting the first direction, the second region being provided around the first region, wherein a pattern density of the second trench is greater than a pattern density of the first trench.

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