Light detection device and electronic apparatus

Abstract

A light detection device according to one embodiment of the present disclosure includes: a semiconductor layer having a plurality of photoelectric conversion parts that perform photoelectric conversion on light; a pad provided on a first surface side of the semiconductor layer; a through hole penetrating the semiconductor layer and electrically connected to the pad; and a first trench penetrating the semiconductor layer at an outer periphery of the through hole and disposed to surround the through hole. In a plan view, the first trench is disposed in a grid pattern on an outer periphery of the through hole.

Description

Technical Field

[0001] The present disclosure relates to a light detection device and an electronic device. Background Art

[0002] There has been proposed a back-side illumination type image pickup device including an electrode pad for external electrical connection and a through portion that penetrates a silicon layer and connects the electrode pad to a wiring. Citation list Patent Literature

[0003] Japanese Unexamined Patent Application Publication No. 2016-115757 Summary of the invention

[0004] It is desirable for a device that detects light to reduce unnecessary parasitic capacitance.

[0005] It is desirable to provide a light detection device that enables reduction of such parasitic capacitance.

[0006] A light detection device according to an embodiment of the present disclosure includes: a semiconductor layer including a plurality of photoelectric conversion units that perform photoelectric conversion on light; a pad disposed on a first surface side of the semiconductor layer; a through hole that penetrates the semiconductor layer and is electrically connected to the pad; and a first groove that is disposed in such a manner that the first groove penetrates the semiconductor layer around the through hole to surround the through hole. The first groove is disposed in such a manner that the first groove forms a grid shape around the through hole in a plan view. An electronic device according to an embodiment of the present disclosure includes: an optical system and a light detection device that receives light passing through the optical system. The light detection device includes: a semiconductor layer including a plurality of photoelectric conversion units that perform photoelectric conversion on light; a pad disposed on a first surface side of the semiconductor layer; a through hole that penetrates the semiconductor layer and is electrically connected to the pad; and a first groove that is disposed in such a manner that the first groove penetrates the semiconductor layer around the through hole to surround the through hole. The first groove is disposed in such a manner that the first groove forms a grid shape around the through hole in a plan view. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] [ Figure 1 ] Figure 1 : is a block diagram showing an example of a schematic configuration of an image pickup device as an example of a light detection device according to an embodiment of the present disclosure. [ Figure 2 ] Figure 2 is a diagram showing an example of a pixel portion of an image pickup device according to an embodiment of the present disclosure. [ Figure 3 ] Figure 3: is a diagram showing a configuration example of a pixel of an image pickup device according to an embodiment of the present disclosure. [ Figure 4 ] Figure 4 is a diagram illustrating an example of a cross-sectional configuration of an image pickup device according to an embodiment of the present disclosure. [ Figure 5 ] Figure 5 is a diagram illustrating an example of a planar configuration of a portion of an image pickup device according to an embodiment of the present disclosure. [ Fig. 6A ] Fig. 6A is a diagram illustrating an example of a method of manufacturing an image pickup device according to an embodiment of the present disclosure. [ Figure 6B ] Figure 6B is a diagram illustrating an example of a method of manufacturing an image pickup device according to an embodiment of the present disclosure. [ Figure 6C ] Figure 6C is a diagram illustrating an example of a method of manufacturing an image pickup device according to an embodiment of the present disclosure. [ Fig.6D ] Fig.6D is a diagram illustrating an example of a method of manufacturing an image pickup device according to an embodiment of the present disclosure. [ Figure 7 ] Figure 7 : is a diagram showing an example of a cross-sectional configuration of an image pickup device according to a first modification example of the present disclosure. [ Figure 8 ] Figure 8 : is a diagram showing an example of a cross-sectional configuration of an image pickup device according to a second modification example of the present disclosure. [ Fig. 9 ] Fig. 9 is a diagram showing another example of the cross-sectional configuration of the image pickup device according to the second modification example of the present disclosure. [ Fig.10 ] Fig.10 is a diagram showing another example of the cross-sectional configuration of the image pickup device according to the second modification example of the present disclosure. [ Fig.11 ] Fig.11 is a diagram showing another example of the cross-sectional configuration of the image pickup device according to the second modification example of the present disclosure. [ Fig.12 ] Fig.12 is a block diagram showing a configuration example of an electronic device including an imaging device. [ Fig.13 ] Fig.13 is a block diagram showing an example of a schematic configuration of a vehicle control system. [ Fig.14 ] Fig.14It is a diagram for assisting in explaining an example of the installation positions of the vehicle exterior information detection unit and the imaging unit. [ Fig.15 ] Fig.15 is a diagram showing an example of a schematic configuration of an endoscopic surgery system. [ Fig.16 ] Fig.16 is a block diagram showing an example of the functional configuration of a camera head and a camera control unit (CCU). DETAILED DESCRIPTION

[0008] Next, details of the embodiments of the present disclosure will be described with reference to the drawings. It should be noted that the description will be given in the following order. 1. Implementation Plan 2. Modifications 3. Application Examples 4. Other application examples

[0009] <1. Implementation Plan> Figure 1 : is a block diagram showing an example of a schematic configuration of an image pickup device as an example of a light detection device according to an embodiment of the present disclosure. Figure 2 is a diagram showing an example of a pixel unit of an image pickup device according to the embodiment. A light detection device is a device capable of detecting incident light. The light detection device can receive light passing through an optical system and generate a signal. An image pickup device 1 used as a light detection device includes a plurality of pixels P having a photoelectric conversion unit, and is configured to perform photoelectric conversion on incident light and generate a signal. The image pickup device 1 can be applied to an image sensor, a distance measuring sensor, etc.

[0010] The light detection device according to the present disclosure can be applied to a distance measuring sensor that enables distance measurement by using a time-of-flight (TOF) method. The light detection device (camera 1) can be applied to a sensor that enables it to detect events, such as an event-driven sensor (also called an event-based vision sensor (EVS), a dynamic vision sensor (DVS), etc.).

[0011] The image pickup device 1 includes pixels P, each of which includes a photoelectric conversion section that is a photodiode and enables photoelectric conversion of light. Figure 2 As shown, the image pickup device 1 includes an image pickup area which is an area (pixel portion 100 ) where a plurality of pixels P are two-dimensionally arranged in a matrix form.

[0012] The imaging device 1 receives incident light (image light) from a subject via an optical system (not shown) including an optical lens. The imaging device 1 captures an image of the subject formed by the optical lens. The imaging device 1 performs photoelectric conversion on the received light and generates a pixel signal. For example, the imaging device 1 is a complementary metal oxide semiconductor (CMOS) image sensor. The imaging device 1 is applicable to electronic devices such as a digital camera, a video camera, or a mobile phone.

[0013] like Figure 2 As shown, it should be noted that the Z-axis direction is the incident direction of light from the subject, the X-axis direction is the left-right direction on the paper orthogonal to the Z-axis direction, and the Y-axis direction is the up-down direction on the paper orthogonal to the Z-axis and the X-axis. Figure 2 The direction of the arrows shown is to illustrate the direction.

[0014] [Schematic Configuration of Image Pickup Device] like Figure 1 As shown in the example of, for example, the image pickup device 1 includes a vertical drive section 111, a signal processing section 112, a horizontal drive section 113, an output section 114, a control section 116, and a terminal section 116 in an area around the pixel section 100. The image pickup device 1 is also provided with a plurality of pixel drive lines Lread and a plurality of vertical signal lines VSL.

[0015] exist Figure 1 In the example shown, the pixel section 100 is connected to a plurality of pixel drive lines Lread provided for respective pixel rows including a plurality of pixels P arranged in a horizontal direction (row direction). Each pixel drive line Lread is a signal line that enables it to transmit a signal to drive the pixel P. The pixel drive line Lsead is configured to transmit a drive signal for reading out a signal from the pixel P. It can also be said that the pixel drive line Lcead is a control line that transmits a signal for controlling the pixel P.

[0016] In addition, the pixel portion 100 is connected to a vertical signal line VSL provided for each pixel column including a plurality of pixels P arranged in a vertical direction (column direction). The vertical signal line VSL is a signal line that enables it to transmit a signal from the pixel P. The vertical signal line VSL is configured to transmit a signal output from the pixel P.

[0017] The vertical driving section 111 includes a shift register, an address decoder, etc. The vertical driving section 111 is configured to drive each pixel P of the pixel section 100. The vertical driving section 111 generates a signal to drive the pixel P, and outputs the signal to each pixel P of the pixel section 100 via a pixel driving line Lread.

[0018] For example, the vertical driving section 111 generates a signal for controlling a transfer transistor, a signal for controlling a reset transistor, and the like, and supplies these signals to each pixel P via a pixel driving line Lread. The vertical driving section 111 is a pixel control section configured to control each pixel P, and can perform control in a manner of reading out a pixel signal from each pixel P. It should be noted that the set of the vertical driving section 110 and the control section 115 may be referred to as a pixel control section.

[0019] The signal processing section 112 is configured to perform signal processing of a pixel signal to be input. For example, the signal processing section 112 includes a load circuit section, an analog-to-digital (AD) conversion section, a horizontal selection switch, etc. The signal output from each pixel P selected and scanned by the vertical driving section 111 is input to the signal processing section 112 through the vertical signal line VSL. The signal processing section 112 performs signal processing such as AD conversion or correlated double sampling (CDS) of the signal of the pixel P.

[0020] The horizontal driving section 113 includes a shift register, an address decoder, etc. The horizontal driving section 113 is configured to drive the horizontal selection switches of the signal processing section 112. The horizontal driving section 113 sequentially drives the horizontal selection switches while scanning the horizontal selection switches of the signal processing section 112. The signals of the respective pixels P transmitted via the respective vertical signal lines VSL are signal-processed by the signal processing section 112, and are sequentially output to the horizontal signal lines 121 through selective scanning of the horizontal driving section 113.

[0021] The output section 114 is configured to perform signal processing on the input signal and output the processed signal. The output circuit 114 performs signal processing on the pixel signals sequentially input from the signal processing section 112 via the horizontal signal line 121, and outputs the processed pixel signals. The output section 114 can perform, for example, buffering, black level adjustment, column variation correction, various types of digital signal processing, etc.

[0022] The control section 115 is configured to control various parts of the image pickup device 1. The control section 115 can receive a clock or data indicating an operation mode provided from the outside, and can also output data such as internal information of the image pickup device 1. The control section 115 includes a timing generator configured to generate various timing signals. The control section 115 controls the driving of peripheral circuits such as the vertical driving section 111, the signal processing section 112, or the horizontal driving section 113 based on the various timing signals (pulse signals, clock signals, etc.) generated by the timing generator.

[0023] The terminal portion 116 is used to exchange signals with the outside. The terminal portion 116 includes pads (terminals) for transmitting signals to the outside, such as pads 51 (described later). For example, the terminal portion 116 includes input / output pads, input pads, output pads, etc. The input / output pads receive and output signals. The input pads receive input signals from the outside of the camera device 1. The output pads output signals to the outside of the camera device 1. In addition, the terminal portion 116 may include power pads and GND pads to supply GND voltage (ground voltage) or power supply voltage input from the outside to various circuits of the camera device 1.

[0024] It should be noted that the vertical drive section 111, the signal processing section 112, the horizontal drive section 113, the horizontal signal line 121, the output section 114, the control section 115, etc. can be mounted on a single semiconductor substrate or on different semiconductor substrates. The imaging device 1 has a structure in which a plurality of substrates are stacked (stacked structure).

[0025] [Pixel structure] Figure 3 : is a diagram showing a configuration example of a pixel of the image pickup device according to the embodiment. The pixel P includes a photoelectric conversion portion 12, a transistor TR, a floating diffusion (FD), a transistor AMP, a transistor SEL, and a transistor RST.

[0026] Each of the transistor TR, the transistor AMP, the transistor SEL, and the transistor RST is a MOS transistor (MOSFET) having a gate, a source, and a drain terminal. Figure 3 In the example shown, the transistors TR, AMP, SEL and RST are implemented by respective NMOS transistors. It should be noted that the transistors of the pixel P may be implemented by PMOS transistors.

[0027] The photoelectric conversion unit 12 is configured to generate electric charges by photoelectric conversion. Figure 3 In the example shown, the photoelectric conversion section 12 is a photodiode (PD), and converts incident light into electric charge. The photoelectric conversion section 12 performs photoelectric conversion, and generates electric charge according to the amount of received light.

[0028] The transistor TR is configured to transfer the charge photoelectrically converted by the photoelectric conversion section 12. Figure 3 As shown, the transistor TR electrically connects or disconnects the photoelectric converter 12 and the FD under the control of the signal STR. The transistor TR is a transfer transistor that can transfer the accumulated charge photoelectrically converted by the photoelectric converter 12 to the FD.

[0029] FD is an accumulation unit configured to accumulate the transferred charge. FD can accumulate the charge that has been photoelectrically converted by the photoelectric conversion unit 12. FD can also be said to be a holding unit that enables the transferred charge to be held. FD accumulates the transferred charge according to the capacitance of FD and converts the charge into a voltage.

[0030] The transistor AMP is configured to generate and output a signal based on the charge accumulated in the FD. Figure 3 As shown, the gate of transistor AMP is electrically connected to FD, and receives input of a voltage converted by FD. The drain of transistor AMP is connected to a power line supplying power supply voltage VDD, and the source is connected to vertical signal line VSL via transistor SEL. Transistor AMP is an amplifying transistor that can generate a signal based on the charge accumulated in FD (i.e., a signal based on the voltage of FD), and can output the generated signal to vertical signal line VSL.

[0031] The transistor SEL is configured to control the output of the signal from the pixel. The transistor SEL is configured to output the signal from the transistor AMP to the vertical signal line VSL under the control of the signal SSEL. The transistor SEL is a selection transistor that can control the output timing of the signal of the pixel. It should be noted that the transistor SEL can be installed between the transistor AMP and the power supply line that supplies the power supply voltage VDD. Alternatively, the transistor SEL can be omitted if necessary.

[0032] The transistor RST is configured to reset the voltage of FD. Figure 3 In the example shown, the transistor RST is configured to be electrically connected to a power line supplying a power supply voltage VDD, and resets the charge of the pixel P. The transistor RST can reset the charge accumulated in the FD and reset the voltage of the FD under the control of the signal SRST. It should be noted that the transistor RST can release the charge accumulated in the photoelectric conversion unit 12 via the transistor TR. The transistor RST is a reset transistor.

[0033] Vertical drive unit 111 (see Figure 1 ) provides control signals to the gates of transistors TR, transistors SEL, transistors RST, etc. of each pixel P via pixel drive lines Lread, and places the transistors in an ON state (conductive state) or an OFF state (non-conductive state). The plurality of pixel drive lines Lread of the imaging device 1 include wiring for transmitting a signal STR to control the transistor TR, wiring for transmitting a signal SSEL to control the transistor SEL, wiring for transmitting a signal SRST to control the transistor RST, etc.

[0034] The vertical driving section 111 performs control to turn on / off the transistor TR, the transistor SEL, the transistor RST, etc. The vertical driving section 111 controls the signal STR, the signal SSEL, the signal SRST, etc. input to each pixel P so that the transistor AMP of each pixel P outputs a signal to the vertical signal line VSL.

[0035] Figure 4 is a diagram showing an example of a cross-sectional configuration of an image pickup device according to the embodiment. Figure 4 An example of a schematic cross-sectional configuration of the imaging device 1 is shown. Figure 5 1 is a diagram showing an example of a planar configuration of a portion of an image pickup device according to an embodiment. Figure 4 As shown in the example of FIG. 1 , the imaging device 1 includes a light receiving section 10 and a light guiding section 20. The light receiving section 10 includes a semiconductor layer 11 having a first surface 11S1 and a second surface 11S2 facing each other. The semiconductor layer 11 includes, for example, a semiconductor substrate (eg, a silicon substrate).

[0036] The light guide 20 is provided on the first surface 11S1 side of the semiconductor layer 11. The wiring layer 90 is provided on the second surface 11S2 side of the semiconductor layer 11. The first surface 11S1 of the semiconductor layer 11 is a light incident surface (light receiving surface). The second surface 11S2 of the semiconductor layer 11 is an element formation surface on which elements such as transistors are formed. The second surface 11S2 of the semiconductor layer 11 is provided with a gate electrode, a gate oxide film, etc.

[0037] The imaging device 1 has a structure in which a light receiving unit 10, a light guiding unit 20, and a wiring layer 90 are stacked in the Z-axis direction. The light guiding unit 20 is provided on the side where light from the optical system enters, and the wiring layer 90 is provided on the side opposite to the light incident side. The imaging device 1 is a so-called back-illuminated imaging device.

[0038] The imaging device 1 is provided with a plurality of pixels P, each of which includes a photoelectric conversion unit 12. Figure 4 As schematically shown, the semiconductor layer 11 includes a plurality of photoelectric conversion sections 12. In the semiconductor layer 11, the plurality of photoelectric conversion sections 12 are two-dimensionally arranged. The light receiving section 10 includes a plurality of photoelectric conversion sections 12 arranged along the first surface 11S1 and the second surface 11S2 of the semiconductor layer 11. For example, the plurality of photoelectric conversion sections 12 are buried in the semiconductor layer 11.

[0039] For example, the wiring layer 90 disposed on the second surface 11S2 side of the semiconductor layer 11 includes a conductive film and an insulating film, and is provided with a plurality of wirings, through holes, etc. For example, the wiring layer 90 includes two or more layers of wirings. The wiring layer 90 has a structure in which a plurality of wirings are stacked with an insulating film interposed therebetween.

[0040] The wiring layer 90 is formed by using aluminum (Al), copper (Cu), tungsten (W), polysilicon (poly-Si), etc. The insulating film is formed by using, for example, silicon oxide (SiO), silicon nitride (SiN), silicon oxynitride (SiON), etc. The insulating film can also be said to be an interlayer insulating film (interlayer insulating layer).

[0041] In the semiconductor layer 11 and the wiring layer 90, for example, the above-mentioned transistors (transistor TR, transistor SEL, transistor RST, transistor AMP, etc.) of each pixel P are formed. In addition, for example, the above-mentioned vertical drive unit 111, signal processing unit 112, horizontal drive unit 113, output unit 114, etc. can also be formed in the semiconductor layer 11 and the wiring layer 90.

[0042] The light guide section 20 is stacked on the light receiving section 10 in the thickness direction orthogonal to the first surface 11S1 of the semiconductor layer 11. The light guide section 20 includes a lens section 21 and a filter 22, and guides light incident from above toward the light receiving section 10. The lens section 21 is an optical member also called an on-chip lens.

[0043] For example, a lens section 21 is provided on the filter 22 for each pixel P or for a plurality of pixels P. The lens section 21 receives light entering from a subject via an optical system (not shown) such as an imaging lens. The photoelectric conversion section 12 performs photoelectric conversion on light incident via the lens section 21 and the filter 22.

[0044] The filter 22 is configured to selectively transmit light of a specific wavelength band in the incident light. The filter 22 is a color filter (R, G, or B), a filter that transmits infrared light, or other filters. For example, a plurality of pixels P provided in the pixel unit 100 of the image pickup device 1 include a plurality of pixels (R pixels) provided with a filter 22 that transmits red light (R), a plurality of pixels (G pixels) provided with a filter 22 that transmits green light (G), and a plurality of pixels (B pixels) provided with a filter 22 that transmits blue light (B).

[0045] In the pixel section 100, a plurality of R pixels, a plurality of G pixels, and a plurality of B pixels are repeatedly arranged. The R pixels generate pixel signals of R components, the G pixels generate pixel signals of G components, and the B pixels generate pixel information of B components. The imaging device 1 enables obtaining pixel signals of R, G, and B.

[0046] It should be noted that the filter provided in the pixel P of the pixel section 100 is not limited to the primary color filter (RGB), but may be a complementary color filter such as cyan (Cy), magenta (Mg), and yellow (Ye). In addition, a filter corresponding to white (W), that is, a filter that transmits light of all wavelengths in the incident light, may also be provided. The filter 22 may be a filter that transmits infrared light.

[0047] In addition, if Figure 4 As shown, the camera device 1 also includes an insulating layer 25, a light shielding portion 26, and a partition 28 using a groove 31. The insulating layer 25 is provided between the layer provided with the filter 22 and the layer provided with the photoelectric conversion portion 12. The insulating layer 25 includes a single-layer film including one selected from the group consisting of, for example, an oxide film (for example, a silicon dioxide film), a nitride film (for example, a silicon nitride film), an oxynitride film, etc., or the insulating layer 25 includes a stacked film including at least two selected therefrom. The insulating layer 25 can also be said to be a planarization layer (planarization film). Note that the light guide portion 20 can also include the insulating layer 25 and the light shielding portion 26.

[0048] The light shielding portion 26 (light shielding film) is implemented by a light shielding member and is provided at the boundary between a plurality of adjacent pixels P. For example, the light shielding portion 26 is formed in the insulating layer 25 and is located above the partition 28. For example, the light shielding portion 26 includes a metal material (aluminum (Al), tungsten (W), copper (Cu), etc.) that blocks light. Figure 4 In the example shown, the light shielding portion 26 is located at the boundary between adjacent lens portions 21 to suppress light leakage to surrounding pixels P. It should be noted that the light shielding portion 26 may include a light absorbing material.

[0049] The partitions 28 are provided between adjacent photoelectric converters 12 to partition the photoelectric converters 12 from each other. The partitions 28 are provided to surround the photoelectric converters 12 in the semiconductor layer 11. The partitions 28 each have a groove 31 (groove portion) formed at a boundary between adjacent pixels P (or photoelectric converters 12).

[0050] exist Figure 4 In the example shown, the partition 28 has a full trench isolation (FTI) structure and is arranged to penetrate the semiconductor layer 11. The groove 31 of the partition 28 can also be said to be a through groove. The groove 31 of the partition 28 is formed in such a way that the groove 31 reaches the second surface 11S2 of the semiconductor layer 11 between a plurality of adjacent photoelectric conversion units 12 to penetrate the semiconductor layer 11. The partition 28 can also be said to be an inter-pixel partition wall or an inter-pixel partition.

[0051] The grooves 31 of the partition 28 are arranged to form a grid shape in a plan view so that the grooves 31 surround each of the plurality of photoelectric conversion units 12. The grooves 31 are arranged in a grid shape on the XY plane. The partition 28 is formed to surround the photoelectric conversion unit 12 on all four sides, and the partition 28 is continuously formed to surround each photoelectric conversion unit 12. For example, an insulating film (insulator) such as an oxide film (e.g., a silicon dioxide film) or a nitride film (e.g., a silicon nitride film) is provided inside the grooves 31 of the partition 28.

[0052] like Figure 4As shown, a semiconductor region 61 is provided on the side wall of the trench 31. The semiconductor region 61 is a predetermined conductive semiconductor region as a semiconductor layer formed by using impurities. For example, the semiconductor region 61 is a p-type semiconductor region as a doped layer doped with p-type impurities. The semiconductor region 61 makes it possible to suppress the generation of dark current.

[0053] In addition, the image pickup device 1 according to the present embodiment is provided with a pad 51, a connection electrode 52, a through hole 53, a groove 32, and a groove 33. Figure 4 As shown, in the image pickup device 1 , the pad 51 , the connection electrode 52 , the through hole 53 , the groove 32 , the groove 33 , and the like are formed in a region around the pixel portion 100 .

[0054] The pad 51 is, for example, an electrode formed by using aluminum (Al). The pad 51 is provided on the first surface 11S1 side, that is, the light incident surface side (light receiving surface side) of the semiconductor layer 11. The pad 51 is a pad electrode, and can also be said to be a terminal (connection terminal) of the image pickup device 1. The image pickup device 1 includes a plurality of pads 51 arranged in the image pickup device 1 and electrically connected to circuit elements of the image pickup device 1. It should be noted that the pad 51 may be formed of a metal material other than aluminum (Al).

[0055] For example, the image pickup device 1 may include a plurality of pads 51 on the first surface 11S1 side of the semiconductor layer 11 in a region outside the pixel portion 100. For example, the plurality of pads 51 of the image pickup device 1 may include pads for transmitting signals to the outside. As described above, the plurality of pads 51 include input / output pads for receiving and outputting signals, input pads for receiving input signals from the outside of the image pickup device 1, output pads for outputting signals to the outside of the image pickup device 1, and other pads.

[0056] exist Figure 4 In the example shown, the pad 51 is formed on the insulating layer 25 and connected to the connection electrode 52. It should be noted that a portion of the pad 51 may be located in the insulating layer 25. The pad 51 may also be formed in the insulating layer 25 in such a manner that the surface (end face) of the pad 51 is exposed from the insulating layer 25.

[0057] The connection electrode 52 is, for example, an electrode formed using tungsten (W). The connection electrode 52 is disposed between the pad 51 and the through hole 53 to electrically connect the pad 51 to the through hole 53. For example, the connection electrode 52 is disposed in the insulating layer 25 and electrically connects the pad 51 to the through hole 53. It should be noted that the connection electrode 52 may include other metal materials. The pad 51 and the connection electrode 52 may also be integrated together.

[0058] The through hole 53 is a through hole that penetrates the semiconductor layer 11. The through hole 53 is formed by using a conductive material, for example. For example, the through hole 53 includes a portion of the semiconductor layer 11 separated by the groove 32. The through hole 53 is provided in such a manner that the semiconductor layer 11 is separated by the groove 32 formed in a grid shape in a plan view (see also Figure 5 ). The grooves 32 are arranged in a grid shape on the XY plane.

[0059] As will be described later, the through hole 53 includes Figure 4 The semiconductor region 61 is formed on the side wall of the trench 32. The through hole 53 is provided between the pad 51 and the wiring layer 90 to electrically connect the pad 51 to the wiring 91 of the wiring layer 90. The through hole 53 is arranged to extend in the Z-axis direction between the pad 51 and the wiring layer 90 and penetrate the semiconductor layer 11. Figure 4 In the illustrated example, the through hole 53 is formed from the wiring 91 of the wiring layer 90 to the connection electrode 52 to connect the wiring 91 in the wiring layer 90 to the connection electrode 52 .

[0060] The trench 32 is a trench (through trench) that penetrates the semiconductor layer 11. For example, an insulating film such as an oxide film (for example, a silicon dioxide film) or a nitride film (for example, a silicon nitride film) is provided inside the trench 32. Figure 4 As shown, a semiconductor region 61 is arranged on the sidewalls of the trench 32 .

[0061] As described above, for example, the semiconductor region 61 is a p-type semiconductor region as a doped layer doped with p-type impurities. The through hole 53 includes the semiconductor region 61 as a conductive region (conductive portion). The pad 51 is electrically connected to the wiring 91 of the wiring layer 90 via the semiconductor region 61 as a conductive region of the through hole 53.

[0062] The groove 33 is provided around the through hole 53 in the semiconductor layer 11. The groove 33 is provided to penetrate the semiconductor layer 11 and surround the through hole 53. For example, an insulating film such as an oxide film or a nitride film is provided inside the groove 33. For example, a silicon dioxide film is embedded in the groove 31 of the partition 28 of the pixel portion 100 and the groove 32 and the groove 33 in the area around the pixel portion 100.

[0063] like Figure 5 As shown, the grooves 33 are arranged in a manner such that the grooves 33 form a grid shape around the through hole 53 in a plan view. The grooves 33 are arranged in a grid shape on the XY plane. In addition, the grooves 33 are arranged outside the pad 51 in a plan view. Figure 4 and Figure 5 As shown, the semiconductor layer 11 includes a plurality of semiconductor regions 41 surrounded by respective trenches 33. The semiconductor device 1 includes a plurality of semiconductor regions 41 surrounding the periphery of the through hole 53.

[0064] The semiconductor device 1 includes a plurality of semiconductor regions 41 arranged to surround a through hole 53 electrically connected to a pad 51. In a plan view, the plurality of semiconductor regions 41 are arranged at intervals along the periphery of the pad 51. Each semiconductor region 41 of the semiconductor layer 11 is a region partitioned by each trench 33, and is in an electrically floating state.

[0065] like Figure 4 and Figure 5 As shown, the semiconductor layer 11 includes a semiconductor region 42 between the through hole 53 and the trench 33. The semiconductor region 42 is a region of the semiconductor layer 11 surrounding the through hole 53. The semiconductor region 42 is divided by the trench 32 and the trench 33, and is in an electrically floating state.

[0066] In addition, if Figure 4 As shown, the semiconductor layer 11 includes a semiconductor region 43 outside the trench 33. The semiconductor region 43 of the semiconductor layer 11 is electrically connected to the wiring 92 of the wiring layer 90, and is supplied with a predetermined potential (voltage) through the wiring. For example, the semiconductor region 43 is supplied with a GND potential (ground potential) through the wiring.

[0067] As described above, in the present embodiment, the groove 33 is arranged in a manner such that the groove 33 forms a grid shape around the through hole 53 in a plan view. This makes it possible to reduce the capacitance applied to the through hole 53. The groove 33 formed in a grid shape around the through hole 53 makes it possible to effectively reduce the unnecessary parasitic capacitance applied to the through hole 53 and the pad 51. This makes it possible to prevent the reduction of the input / output (I / O) speed. Therefore, the transmission characteristics of the signal in the pad 51 and the through hole 53 can be improved.

[0068] In addition, as described above, the semiconductor regions 41 and 42 around the through hole 53 are in an electrically floating state. This makes it possible to suppress the formation of a large capacitance (electrostatic capacitance) of the through hole 53. Therefore, it is possible to suppress a decrease in signal level and a signal delay in the through hole 53, the pad 51, etc., and realize high-speed signal transmission.

[0069] Furthermore, in the present embodiment, the groove 31 of the pixel portion 100, the groove 32 in the region around the pixel portion 100, and the groove 33 form the same grid shape. This enables the groove 31, the groove 32, and the groove 33 to be formed simultaneously in the manufacturing steps, and the number of steps can be reduced. This enables an increase in the manufacturing cost of the image pickup device 1 to be suppressed.

[0070] In addition, in the present embodiment, the semiconductor region 61 of the partition 28 and the semiconductor region 61 as the conductive region of the through hole 53 are formed by using the same impurity material. This enables the partition 28 and the through hole 53 to be formed simultaneously, and the number of steps can be further reduced.

[0071] FIG. 6A to FIG. 6D 1 is a diagram showing an example of a method for manufacturing an image pickup device according to an embodiment of the present invention. Fig. 6A As shown, the semiconductor layer 11 formed with the photoelectric conversion unit 12 and the like is subjected to chemical mechanical polishing (CMP) and then the inside of the grooves 31 to 32 is wet-etched. Figure 6B As shown, an insulating member such as silicon dioxide (SiO 2 ) is embedded in the trenches 31 to 33 .

[0072] Next, if Figure 6C As shown in FIG. 1 , the connection electrode 52 is formed in the region around the pixel portion 100, and the light shielding portion 26 is formed in the pixel portion 100. The connection electrode 52 and the light shielding portion 26 are formed by using the same metal material (such as tungsten). Fig.6D As shown, an insulating film such as a silicon dioxide (SiO 2 ) film is formed around the connection electrode 52 and the light shielding portion 26 , and the pad 51 and the filter 22 are sequentially formed on the insulating layer 25 .

[0073] The pad 51 is formed on the connection electrode 52, and the filter 22 is formed on the insulating layer 25 including the light shielding portion 26. Next, the lens portion 21 is formed on the filter 22. By using the above-mentioned manufacturing method, it is possible to manufacture Figure 4 It should be noted that the above-described manufacturing method is merely an example, and other manufacturing methods may be employed.

[0074] [Function and Effect] The light detecting device according to the present embodiment includes: a semiconductor layer (semiconductor layer 11) including a plurality of photoelectric conversion units (photoelectric conversion units 12) that perform photoelectric conversion on light; a pad (pad 51) provided on the first surface side of the semiconductor layer; a through hole (through hole 53) that penetrates the semiconductor layer and is electrically connected to the pad; and a first groove (groove 33) provided in such a manner that the first groove penetrates the semiconductor layer around the through hole to surround the through hole. The first groove is provided in such a manner that the first groove forms a grid shape around the through hole in a plan view.

[0075] The light detecting device (imaging device 1) according to the present embodiment includes the grooves 33 arranged in such a manner that the grooves 33 form a lattice shape around the through hole 53 in a plan view. This makes it possible to reduce unnecessary parasitic capacitance applied to the through hole 53. A light detecting device that enables reduction of such parasitic capacitance can be provided.

[0076] Next, a modification of the present disclosure will be described. Hereinafter, structural elements similar to those of the above-described embodiment will be denoted by the same reference numerals as those of the above-described embodiment, and repeated descriptions will be appropriately omitted.

[0077] <2. Modifications> (2-1. First Modification) In the above-described embodiment, there has been described an example of the configuration of the light detection device 1. However, the configuration of the light detection device (imaging device 1) is not limited thereto. Figure 7 1 is a diagram showing an example of a cross-sectional configuration of an image pickup device according to a first modification. Figure 7 As shown, the image pickup device 1 may include a pinning film 62. For example, the pinning film 62 includes a metal compound (metal oxide, metal nitride, etc.), and may also be said to be a metal compound layer.

[0078] The pinning film 62 is a film having fixed charge and is formed by using a high dielectric. For example, the pinning film 62 is a film having negative fixed charge and suppresses generation of dark current on the interface of the semiconductor layer 11. The pinning film 62 can also be said to be a fixed charge film.

[0079] For example, the pinning film 62 includes at least one of oxides of chemical elements such as hafnium (Hf), zirconium (Zr), aluminum (Al), titanium (Ti), tantalum (Ta), magnesium (Mg), yttrium (Y), or lanthanide (La). The pinning film 62 may be provided on the respective sidewalls of the trenches 31 to 33.

[0080] exist Figure 7 In the example shown, the pinning film 62 is provided in the grooves 31 to 33 in such a manner that the pinning film 62 covers the side walls of the grooves 31 to 33. The pinning film 62 is arranged beside the semiconductor region 61. The through hole 53 includes the pinning film 62 as a part of the conductive region (conductive portion). The pad 51 makes it possible to electrically connect to the wiring 91 of the wiring layer 90 via the pinning film 62 as the conductive region of the through hole 53. Also, in this modification, effects similar to those of the above-described embodiment can be achieved.

[0081] It should be noted that in Figure 7 In the example shown, the through hole 53 includes a plurality of semiconductor regions 61 and a pinning film 62 as a conductive region. The pad 51 is electrically connected to the wiring 91 of the wiring layer 90 via the plurality of semiconductor regions 61 and the pinning film 62. For example, the pinning film 62 having a negative fixed charge makes it possible to increase the hole concentration in the region adjacent to the pinning film 62, which makes it possible to reduce the resistance of the through hole 53.

[0082] (2-2. Second Modification) Figure 8 1 is a diagram showing an example of a cross-sectional configuration of an image pickup device according to a second modification. Figure 8As shown, a metal film 63 may be embedded in the groove 31 of the partition 28. The metal film 63 includes a metal material such as tungsten (W), aluminum (Al), or cobalt (Co). The metal film 63 disposed inside the groove 31 enables light leakage to surrounding pixels P to be suppressed.

[0083] The metal material embedded in the groove 32 may be the same as the metal material embedded in the groove 31. Figure 8 In the example shown, the metal film 63 is also provided inside the groove 32 below the connection electrode 52 in a similar manner to the groove 31. In this case, the through hole 53 includes the metal film 63 as a part of the conductive region (conductive portion). The pad 51 makes it possible to electrically connect to the wiring 91 of the wiring layer 90 via the metal film 63 as the conductive region of the through hole 53. Also in this modification, an effect similar to that of the above-described embodiment can be achieved.

[0084] It should be noted that in Figure 8 In the example shown, the spacing between the grooves 32 or 33 (the spacing between the grooves 32 or 33) is substantially the same as the spacing between the grooves 31 (the spacing between the grooves 31). Fig. 9 As shown in the example of , the spacing between the grooves 32 or 33 may be different from the spacing between the grooves 31. For example, the spacing between the grooves 32 or 33 in the area around the pixel portion 100 may be wider than the spacing between the grooves 31 of the pixel portion 100. Fig. 9 In the example, the pitch of the grooves 32 or 33 in the X-axis direction and the Y-axis direction is wider than the pitch between the grooves 31 .

[0085] In addition, if Fig.10 As shown in the example of FIG. 5 , the metal film 63 can be disposed inside more trenches 32. This makes it possible to reduce the resistance of the through hole 53. Fig.10 As shown, the through hole 53 can be realized by a metal film 63 embedded in each groove under the pad 51. This makes it possible to reduce the resistance of the through hole 53. Fig.11 As shown, a metal film 63 may also be provided inside the trench 33 around the through hole 53 .

[0086] <3. Application Examples> The above-described imaging device 1 and the like are applicable to any type of electronic equipment having an imaging function, such as a camera system such as a digital camera or a video camera, or a mobile phone having an imaging function and the like. Fig.12 A schematic configuration of an electronic device 1000 is shown.

[0087] The electronic device 1000 includes, for example, a lens group 1001, an image pickup device 1, a digital signal processor (DSP) circuit 1002, a frame memory 1003, a display unit 1004, a storage unit 1005, an operation unit 1006, and a power supply unit 1007. They are connected to each other via a bus 1008.

[0088] The lens group 1001 receives incident light (image light) from a subject and forms an image on an imaging plane of the imaging device 1. The imaging device 1 converts the amount of incident light formed as an image on the imaging plane by the lens group 1001 into an electrical signal in units of pixels, and supplies the electrical signal to the DSP circuit 1002 as a pixel signal.

[0089] The DSP circuit 1002 is a signal processing circuit that processes a signal supplied from the imaging device 1. The DSP circuit 1002 outputs image data obtained by processing the signal from the imaging device 1. The frame memory 1003 temporarily stores the image data processed by the DSP circuit 1002 in units of frames.

[0090] The display unit 1004 includes, for example, a panel-type display device such as a liquid crystal panel or an organic electroluminescence (EL) panel, and records image data of a moving image or a still image captured by the camera 1 in a recording medium such as a semiconductor memory or a hard disk.

[0091] The operation unit 1006 outputs operation signals for various functions of the electronic device 1000 according to the user's operation. The power supply unit 1007 appropriately supplies various powers for the operation of these power supply targets to the DSP circuit 1002, frame memory 1003, display unit 1004, storage unit 1005, and operation unit 1006.

[0092] <4. Application Examples> (Application example of mobile object) The technology according to the present disclosure (the present technology) is applicable to various products. For example, the technology according to the present disclosure can be implemented as a device installed on any type of mobile body including automobiles, electric vehicles, hybrid vehicles, motorcycles, bicycles, personal mobile devices, airplanes, drones, ships, robots, etc.

[0093] Fig.13 : is a block diagram showing an example of a schematic configuration of a vehicle control system as an example of a moving body control system to which the technology according to the embodiment of the present invention can be applied.

[0094] The vehicle control system 12000 includes a plurality of electronic control units connected to each other via a communication network 12001. Fig.13In the example shown, the vehicle control system 12000 includes a drive system control unit 12010, a body system control unit 12020, an external information detection unit 12030, an internal information detection unit 12040, and an integrated control unit 12050. In addition, as a functional configuration of the integrated control unit 12050, a microcomputer 12051, a sound / image output unit 12052, and an in-vehicle network interface (I / F) 12053 are shown.

[0095] The drive system control unit 12010 controls the operation of devices related to the drive system of the vehicle according to various types of programs. For example, the drive system control unit 12010 serves as a control device for the following devices: a drive force generating device such as an internal combustion engine or a drive motor for generating a vehicle drive force, a drive force transmitting 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 vehicle braking force.

[0096] The body system control unit 12020 controls the operation of various types of devices provided on the vehicle body according to various types of programs. For example, the body system control unit 12020 is used as a control device for a keyless entry system, a smart key system, a power window device, or various lights such as a headlight, a reverse light, a brake light, a turn signal light, or a fog light. In this case, a radio wave transmitted from a mobile device that replaces the key or a signal of various types of switches may be input to the body system control unit 12020. The body system control unit 12020 receives input of these radio waves or signals, and controls a door lock device, a power window device, or a light, etc. of the vehicle.

[0097] The vehicle exterior information detection unit 12030 detects information outside the vehicle including the vehicle control system 12000. For example, the vehicle exterior information detection unit 12030 is connected to the camera unit 12031. The vehicle exterior information detection unit 12030 causes the camera unit 12031 to capture an image of the vehicle exterior and receives the captured image. Based on the received image, the vehicle exterior information detection unit 12030 can perform detection processing of objects such as people, vehicles, obstacles, signs, or characters on the road surface, or can perform detection processing of the distance to the above-mentioned objects.

[0098] 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 can output the electrical signal as distance measurement information. In addition, the light received by the imaging unit 12031 can be visible light, or can be invisible light such as infrared rays.

[0099] The in-vehicle information detection unit 12040 detects information about the interior of the vehicle. The in-vehicle information detection unit 12040 is connected to, for example, a driver state detection unit 12041 that detects the driver's state. The driver state detection unit 12041 includes, for example, a camera that takes a picture of the driver. Based on the detection information input from the driver state detection unit 12041, the in-vehicle information detection unit 12040 can calculate the driver's fatigue level or the driver's concentration level, or can determine whether the driver is dozing off.

[0100] The microcomputer 12051 can calculate the control target value of the driving force generating device, the steering mechanism or the braking device based on the information outside or inside the vehicle obtained by the vehicle outside information detection unit 12030 or the vehicle inside information detection unit 12040, and output the control command to the driving system control unit 12010. For example, the microcomputer 12051 can perform cooperative control aimed at realizing the functions of the advanced driver assistance system (ADAS), including collision avoidance or impact mitigation of the vehicle, following driving based on the vehicle-to-vehicle distance, speed maintenance driving, vehicle collision warning or vehicle lane departure warning, etc.

[0101] In addition, by controlling the driving force generating device, steering mechanism or braking device, etc. based on the information outside or inside the vehicle obtained by the external information detection unit 12030 or the internal information detection unit 12040, the microcomputer 12051 can perform collaborative control aimed at achieving automatic driving, etc., wherein the automatic driving enables the vehicle to drive autonomously without relying on the driver's operation.

[0102] In addition, based on the information outside the vehicle obtained by the vehicle exterior information detection unit 12030, the microcomputer 12051 can output a control command to the body system control unit 12020. For example, the microcomputer 12051 can perform cooperative control aimed at preventing glare by controlling the headlights to change from high beam to low beam, for example, according to the position of the preceding vehicle or the oncoming vehicle detected by the vehicle exterior information detection unit 12030.

[0103] The sound / image output unit 12052 sends an output signal of at least one of sound and image to an output device capable of visually or auditorily notifying the vehicle's passengers or the outside of the vehicle of information. Fig.13 In the example of , as the output device, an audio speaker 12061, a display portion 12062, and an instrument panel 12063 are shown. For example, the display portion 12062 may include at least one of an in-vehicle display and a head-up display.

[0104] Fig.14 12031 is a diagram showing an example of the installation position of the camera unit 12031.

[0105] exist Fig.14 In the figure, the camera unit 12031 includes camera units 12101, 12102, 12103, 12104 and 12105.

[0106] The camera units 12101, 12102, 12103, 12104 and 12105 are, for example, arranged at the front nose, rearview mirror, rear bumper and rear door of the vehicle 12100 and at the upper part of the windshield in the vehicle compartment. The camera unit 12101 arranged at the front nose and the camera unit 12105 arranged at the upper part of the windshield in the vehicle compartment mainly obtain images in front of the vehicle 12100. The camera units 12102 and 12103 arranged at the rearview mirror mainly obtain images on both sides of the vehicle 12100. The camera unit 12104 arranged at the rear bumper or rear door mainly obtains images behind the vehicle 12100. The camera unit 12105 arranged at the upper part of the windshield in the vehicle compartment is mainly used to detect the vehicle in front, pedestrians, obstacles, traffic lights, traffic signs or lanes, etc.

[0107] By the way, Fig.14 An example of the imaging range of the imaging units 12101 to 12104 is shown. The imaging range 12111 indicates the imaging range of the imaging unit 12101 provided at the front nose. The imaging ranges 12112 and 12113 respectively indicate the imaging ranges of the imaging units 12102 and 12103 provided at the rearview mirror. The imaging range 12114 indicates the imaging range of the imaging unit 12104 provided at the rear bumper or the rear door. For example, by superimposing the image data captured by the imaging units 12101 to 12104, a bird's-eye view image of the vehicle 12100 observed from above is obtained.

[0108] At least one of the imaging units 12101 to 12104 may have a function of obtaining distance information. For example, at least one of the imaging units 12101 to 12104 may be a stereo camera composed of a plurality of imaging elements, or may be an imaging element having pixels for phase difference detection.

[0109] For example, based on the distance information obtained from the camera units 12101 to 12104, the microcomputer 12051 can determine the distance to each three-dimensional object within the camera ranges 12111 to 12114 and the time change of the distance (relative speed with respect to the vehicle 12100), thereby extracting the nearest three-dimensional object as the front vehicle, in particular, the three-dimensional object exists on the driving path of the vehicle 12100 and travels in the same direction as the vehicle 12100 at a predetermined speed (e.g., equal to or greater than 0 km / h). In addition, the microcomputer 12051 can pre-set the inter-vehicle distance to be maintained with the front vehicle, and perform automatic braking control (including follow-up stop control) or automatic acceleration control (including follow-up start control), etc. Therefore, cooperative control such as automatic driving, which is intended to make the vehicle travel autonomously without relying on the driver's operation, can be performed.

[0110] For example, based on the distance information obtained from the camera units 12101 to 12104, the microcomputer 12501 can classify the three-dimensional object data of the three-dimensional object into three-dimensional object data of two-wheeled vehicles, standard vehicles, large vehicles, pedestrians, utility poles, and other three-dimensional objects, extract the classified three-dimensional object data, and use the extracted three-dimensional object data to automatically avoid obstacles. For example, the microcomputer 12051 identifies obstacles around the vehicle 12100 as obstacles that the driver of the vehicle 12100 can visually identify and obstacles that the driver of the vehicle 12100 is difficult to visually identify. Then, the microcomputer 12051 determines a collision risk indicating the risk of collision with each obstacle. In the case where the collision risk is equal to or higher than the set value and therefore there is a possibility of collision, the microcomputer 12051 outputs a warning to the driver via the audio speaker 12061 or the display unit 12062, and performs forced deceleration or evasive steering via the drive system control unit 12010. Therefore, the microcomputer 12051 can assist driving to avoid collisions.

[0111] At least one of the camera units 12101 to 12104 may be an infrared camera that detects infrared rays. The microcomputer 12051 may identify a pedestrian, for example, by determining whether a pedestrian exists in the camera images of the camera units 12101 to 12104. For example, such identification of pedestrians is performed by the following steps: a step of extracting feature points in the camera images of the camera units 12101 to 12104 as infrared cameras; and a step of performing pattern matching processing on a series of feature points representing the contour of an object to determine whether it is a pedestrian. If the microcomputer 12051 determines that a pedestrian exists in the camera images of the camera units 12101 to 12104 and thus identifies the pedestrian, the sound / image output unit 12052 controls the display unit 12062 so that a square contour line for emphasis is displayed in a manner superimposed on the identified pedestrian. The sound / image output unit 12052 may also control the display unit 12062 so that an icon representing a pedestrian or the like is displayed at a desired position.

[0112] An example of a mobile body control system to which the technology of the present disclosure can be applied has been described above. The technology of the present disclosure can be applied to the camera unit 12031 among the above components. Specifically, for example, the camera device 1 and the like can be applied to the camera unit 12031. By applying the technology of the present disclosure to the camera unit 12031, a signal can be appropriately transmitted. Therefore, in the mobile body control system, high-precision control can be performed using the captured image.

[0113] (Application example of endoscopic surgery system) The technology according to the present disclosure (the present technology) is applicable to various products. For example, the technology according to the present disclosure is applicable to an endoscopic surgery system.

[0114] Fig.15 : is a view showing a schematic configuration example of an endoscopic surgery system to which the technology according to an embodiment of the present disclosure (the present technology) can be applied.

[0115] exist Fig.15 , a state is shown in which a surgeon (doctor) 11131 is using an endoscopic surgery system 11000 to perform surgery on a patient 11132 on a bed 11133. As shown in the figure, the endoscopic surgery system 11000 includes an endoscope 11100, other surgical tools 11110 (e.g., a pneumoperitoneum tube 11111 and an energy device 11112), a support arm device 11120 (supporting the endoscope 11100 thereon), and a cart 11200, on which various devices used for endoscopic surgery are loaded.

[0116] The endoscope 11100 includes a lens barrel 11101 and a camera 11102 connected to the proximal end of the lens barrel 11101, and the lens barrel 11101 has a region of a predetermined length from its distal end for insertion into a body cavity of a patient 11132. In the illustrated example, the endoscope 11100 is illustrated as a rigid endoscope including the lens barrel 11101 as having a hard type. However, the endoscope 11100 may also be a flexible endoscope including the lens barrel 11101 as having flexibility.

[0117] The lens barrel 11101 has an opening at its distal end for mounting an objective lens. The light source device 11203 is connected to the endoscope 11100 so that the light generated by the light source device 11203 is guided to the distal end of the lens barrel 11101 through a light guide extending inside the lens barrel 11101 and irradiated toward an observation target in the body cavity of the patient 11132 through the objective lens. It should be noted that the endoscope 11100 may be a forward-looking endoscope, or may be an oblique-looking endoscope or a side-looking endoscope.

[0118] An optical system and an imaging element are provided inside the camera head 11102, so that the reflected light (observation light) from the observation target is gathered on the imaging element by the optical system. The imaging element performs photoelectric conversion on the observation light to generate an electrical signal corresponding to the observation light, that is, an image signal corresponding to the observation image. The image signal is transmitted to the camera control unit (CCU) 11201 as raw data.

[0119] The CCU 11201 includes a central processing unit (CPU), a graphics processing unit (GPU), etc., and centrally controls the operations of the endoscope 11100 and the display device 11202. In addition, the CCU 11201 receives an image signal from the camera 11102, and performs various image processing for displaying an image based on the image signal, such as development processing (demosaic processing), on the image signal.

[0120] The display device 11202 displays an image based on an image signal that has been image-processed by the CCU 11201 under the control of the CCU 11201 .

[0121] The light source device 11203 includes a light source such as, for example, a light emitting diode (LED), and provides illumination light to the endoscope 11100 when imaging a surgical field.

[0122] The input device 11204 is an input interface for the endoscopic surgery system 11000. The user can input various types of information or instructions to the endoscopic surgery system 11000 through the input device 11204. For example, the user will input instructions to change the image capturing conditions (type of irradiation light, magnification or focal length, etc.) of the endoscope 11100.

[0123] The treatment tool control device 11205 controls the driving of the energy device 11112 for cauterizing or cutting tissue, sealing blood vessels, etc. The pneumoperitoneum device 11206 delivers gas into the body cavity of the patient 11132 through the pneumoperitoneum tube 11111 to inflate the body cavity to ensure the field of view of the endoscope 11100 and to ensure the working space of the surgeon. The recorder 11207 is a device capable of recording various types of information related to the operation. The printer 11208 is a device capable of printing various types of information related to the operation in various forms (such as text, images, or graphics).

[0124] It should be noted that the light source device 11203 that provides the irradiation light when the surgical area is to be imaged to the endoscope 11100 may include a white light source such as an LED, a laser light source, or a combination thereof. In the case where the white light source includes a combination of red, green, and blue (RGB) laser light sources, since the output intensity and output timing of each color (each wavelength) can be controlled with high precision, the white balance adjustment of the captured image can be performed by the light source device 11203. In addition, in this case, if the laser beams from each RGB laser light source are irradiated onto the observation target in a time-division manner, and the drive of the imaging element of the camera 11102 is controlled synchronously with the irradiation timing, it is also possible to capture images corresponding to each of the R, G, and B colors in a time-division manner. According to this method, a color image can be obtained even if a color filter is not provided for the imaging element.

[0125] In addition, the light source device 11203 can be controlled so that the intensity of the light to be output changes at predetermined intervals. By controlling the driving of the imaging element of the camera 11102 in synchronization with the timing of the change in light intensity, images are acquired in a time-division manner and synthesized, and a high dynamic range image without underexposed shadows and overexposed highlights can be generated.

[0126] In addition, the light source device 11203 can be constructed to provide light of a predetermined wavelength band that can be used for special light observation. In special light observation, for example, by utilizing the wavelength dependence of light absorption in human tissue to irradiate light having a narrower wavelength band than the irradiation light (i.e., white light) during ordinary observation, narrow-band light observation is performed to image predetermined tissues (e.g., blood vessels of the surface layer of the mucosa, etc.) with high contrast. Alternatively, in special light observation, fluorescence observation for obtaining images by fluorescence generated by irradiation with excitation light can be performed. In fluorescence observation, fluorescence from body tissue can be observed by irradiating excitation light onto body tissue (autofluorescence observation) or a fluorescent image can be obtained by locally injecting an agent (such as indocyanine green (ICG)) into human tissue and irradiating excitation light corresponding to the fluorescence wavelength of the agent onto human tissue. The light source device 11203 can be constructed to provide narrow-band domain light and / or excitation light suitable for the above-mentioned special light observation.

[0127] Fig.16 It shows Fig.15 A block diagram of an example of the functional configuration of the camera 11102 and the CCU 11201 shown.

[0128] The camera 11102 includes a lens unit 11401, an imaging unit 11402, a driving unit 11403, a communication unit 11404, and a camera control unit 11405. The CCU 11201 includes a communication unit 11411, an image processing unit 11412, and a control unit 11413. The camera 11102 and the CCU 11201 are connected to each other through a transmission cable 11400 for communication.

[0129] The lens unit 11401 is an optical system provided at a position connected to the lens barrel 11101. Observation light taken from the distal end of the lens barrel 11101 is guided to the camera head 11102 and introduced into the lens unit 11401. The lens unit 11401 includes a combination of a plurality of lenses including a zoom lens and a focus lens.

[0130] The number of imaging elements included in the imaging unit 11402 can be one (single-board type) or multiple (multi-board type). For example, in the case where the imaging unit 11402 is configured as a multi-board type imaging unit, image signals corresponding to each of R, G and B are generated by the imaging element, and the image signals can be synthesized to obtain a color image. The imaging unit 11402 can also be constructed to have a pair of imaging elements for respectively acquiring image signals for the right eye and for the left eye, thereby being used for three-dimensional (3D) display. If 3D display is performed, the surgeon 11131 can more accurately understand the depth of living tissue in the surgical area. It should be noted that in the case where the imaging unit 11402 is configured as a stereoscopic type imaging unit, multiple systems of lens units 11401 are provided corresponding to the respective imaging elements.

[0131] In addition, the imaging unit 11402 does not have to be provided on the camera head 11102. For example, the imaging unit 11402 may be provided inside the lens barrel 11101 just behind the objective lens.

[0132] The driving unit 11403 includes an actuator, and moves the zoom lens and the focus lens of the lens unit 11401 by a predetermined distance along the optical axis under the control of the camera control unit 11405. Therefore, the magnification and focus of the image captured by the imaging unit 11402 can be appropriately adjusted.

[0133] The communication unit 11404 includes a communication device for sending and receiving various types of information to and from the CCU 11201. The communication unit 11404 sends an image signal acquired from the imaging unit 11402 to the CCU 11201 through the transmission cable 11400 as RAW data.

[0134] In addition, the communication unit 11404 receives a control signal for controlling the driving of the camera 11102 from the CCU 11201, and provides the control signal to the camera control unit 11405. The control information includes information related to imaging conditions, such as, for example, information specifying a frame rate for capturing an image, information specifying an exposure value when capturing an image, and / or information specifying a magnification and a focus for capturing an image.

[0135] It should be noted that image capturing conditions such as frame rate, exposure value, magnification, or focus may be specified by a user or may be automatically set based on an acquired image signal by the control unit 11413 of the CCU 11201. In the latter case, an automatic exposure (AE) function, an automatic focus (AF) function, and an automatic white balance (AWB) function are incorporated in the endoscope 11100.

[0136] The camera control unit 11405 controls the driving of the camera 11102 based on the control signal received from the CCU 11201 through the communication unit 11404 .

[0137] The communication unit 11411 includes a communication device for sending various types of information to the camera 11102 and receiving various types of information from the camera 11102. Through the transmission cable 11400, the communication unit 11411 receives an image signal sent thereto from the camera 11102.

[0138] In addition, the communication unit 11411 sends a control signal for controlling the driving of the camera 11102 to the camera 11102. The image signal and the control signal can be transmitted through electrical communication, optical communication, etc.

[0139] The image processing unit 11412 performs various image processing on the image signal in the form of RAW data sent thereto from the camera 11102 .

[0140] The control unit 11413 performs various types of control related to imaging of the operation area, etc. by the endoscope 11100 and display of the captured image obtained by imaging the operation area, etc. For example, the control unit 11413 generates a control signal for controlling the driving of the camera head 11102 .

[0141] In addition, the control unit 11413 controls the display device 11202 to display a captured image of the surgical area, etc., based on the image signal that has been image-processed by the image processing unit 11412. Therefore, the control unit 11413 can use various image recognition technologies to recognize various objects in the captured image. For example, the control unit 11413 can recognize surgical tools such as forceps, specific living areas, bleeding, fog when the energy device 11112 is used, etc. by detecting the shape, color, etc. of the edge of the object contained in the captured image. When the control unit 11413 controls the display device 11202 to display the captured image, the control unit 11413 can use the recognition result to display various types of surgical support information in a manner overlapping with the image of the surgical area. When the surgical support information is displayed in an overlapping manner and presented to the surgeon 11131, the burden of the surgeon 11131 can be reduced, and the surgeon 11131 can reliably perform surgery.

[0142] The transmission cable 11400 connecting the camera head 11102 and the CCU 11201 to each other is an electric signal cable capable of being used for electric signal communication, an optical fiber capable of being used for optical communication, or a composite cable capable of being used for electric communication and optical communication.

[0143] Here, although in the illustrated example, communication is performed by wired communication using the transmission cable 11400, communication between the camera 11102 and the CCU 11201 may be performed by wireless communication.

[0144] An example of an endoscopic surgical 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 preferably be applied to the camera unit 11402 of the camera head 11102 provided in the endoscope 11100 among the above-mentioned components. Applying the technology according to the present disclosure to the camera unit 11402 enables the camera unit 11402 to be sensitive and provide a high-resolution endoscope 11100.

[0145] The present disclosure has been described above with reference to the embodiments, variations, application examples, and further application examples. However, the present technology is not limited thereto, and various variations may be made thereto. For example, the above variations have been described as variations of the embodiments. In addition, the structural elements according to the various variations may be appropriately combined for use.

[0146] According to an embodiment of the present disclosure, a light detecting device includes: a semiconductor layer including a plurality of photoelectric conversion units for photoelectrically converting light; a pad disposed on a first surface side of the semiconductor layer; a through hole penetrating the semiconductor layer and electrically connected to the pad; and a first groove, which is disposed in such a manner that the first groove penetrates the semiconductor layer around the through hole to surround the through hole. The first groove is disposed in such a manner that the first groove forms a grid shape around the through hole in a plan view. This makes it possible to reduce unnecessary parasitic capacitance to be applied to the through hole. A light detecting device that makes it possible to reduce such parasitic capacitance can be provided.

[0147] It should be noted that the effects described herein are for illustrative purposes only, and there may be other effects. In addition, the present technology may be configured as follows. (1) A light detection device, comprising: a semiconductor layer including a plurality of photoelectric conversion sections that perform photoelectric conversion on light; a pad disposed on the first surface side of the semiconductor layer; a through hole penetrating the semiconductor layer and electrically connected to the pad; and a first trench provided in such a manner that the first trench penetrates the semiconductor layer around the through hole to surround the through hole, The first grooves are arranged in such a way that the first grooves form a grid shape around the through hole in a plan view. (2) The light detection device according to (1), wherein The semiconductor layer includes a plurality of first semiconductor regions surrounded by respective first trenches disposed around the through holes, and The plurality of first semiconductor regions are arranged to surround the through hole. (3) The light detecting device according to (2), wherein the first semiconductor region is in an electrically floating state. (4) The light detection device according to any one of (1) to (3), wherein The semiconductor layer includes a second semiconductor region between the through hole and the first trench, and The second semiconductor region is in an electrically floating state. (5) The light detecting device according to any one of (1) to (4), wherein the first groove is provided outside the pad in a plan view. (6) The light detection device according to any one of (1) to (5), comprising a second trench adjacent to the through hole and penetrating the semiconductor layer, The through hole includes a semiconductor region doped with impurities on a sidewall of the second trench. (7) The light detection device according to any one of (1) to (6), comprising a second trench adjacent to the through hole and penetrating the semiconductor layer, Wherein, the through hole includes a pinning film disposed on a sidewall of the second trench. (8) The light detection device according to any one of (1) to (7), comprising a second trench provided with the through hole and penetrating the semiconductor layer, Wherein, the through hole comprises a metal material disposed in the second groove. (9) The light detection device according to any one of (1) to (8), comprising The third trench is provided to penetrate the semiconductor layer between the adjacent plurality of photoelectric conversion portions and surround each of the plurality of photoelectric conversion portions. (10) The light detecting device according to (9), wherein the first groove and the third groove are formed with the same lattice shape in a plan view. (11) The light detection device according to (9) or (10) comprises a second trench adjacent to the through hole and penetrating the semiconductor layer, The second groove and the third groove are formed in the same grid shape in a plan view. (12) The light detection device according to any one of (9) to (11), comprising: a second trench adjacent to the through hole and penetrating the semiconductor layer; and A semiconductor region is disposed on the sidewall of the second trench and the sidewall of the third trench and is doped with impurities. (13) The light detection device according to any one of (9) to (12), comprising: a second trench adjacent to the through hole and penetrating the semiconductor layer; and A pinning film is provided on a sidewall of the second trench and a sidewall of the third trench. (14) The light detection device according to any one of (9) to (13), comprising a second trench provided with the through hole and penetrating the semiconductor layer, Wherein, the second groove and the third groove are embedded with the same metal material. (15) The light detecting device according to any one of (9) to (14), wherein the light detecting device has a back side illumination structure. (16) The light detection device according to any one of (9) to (15), comprising: a lens disposed on the first surface side of the semiconductor layer; and A wiring layer is provided on a second surface side of the semiconductor layer opposite to the first surface. (17) An electronic device, comprising: Optical systems; and a light detection device that receives light that passes through the optical system, Wherein, the light detection device comprises: a semiconductor layer including a plurality of photoelectric conversion sections that perform photoelectric conversion on light; a pad disposed on the first surface side of the semiconductor layer; a through hole penetrating the semiconductor layer and electrically connected to the pad; and a first trench, which is provided in such a manner that the first trench penetrates the semiconductor layer around the through hole to surround the through hole, and The first grooves are arranged in such a manner that the first grooves form a lattice shape around the through hole in a plan view.

[0148] This application claims the benefit of Japanese Patent Application JP2022-144731 filed in the Japan Patent Office on September 12, 2022, the entire contents of which are incorporated herein by reference.

[0149] It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and substitutions may be made according to design requirements and other factors as long as they are within the scope of the appended claims or the equivalents thereof.

Claims

1. A light detection device, comprising: a semiconductor layer including a plurality of photoelectric conversion sections that perform photoelectric conversion on light; a pad disposed on the first surface side of the semiconductor layer; a through hole penetrating the semiconductor layer and electrically connected to the pad; and A first trench is arranged to penetrate the semiconductor layer around the through hole and surround the through hole. Wherein, in a plan view, the first grooves are arranged in a grid shape around the through hole.

2. The light detection device according to claim 1, wherein The semiconductor layer includes a plurality of first semiconductor regions surrounded by respective first trenches disposed around the through holes, and The plurality of first semiconductor regions are arranged to surround the through hole. The light detecting device according to claim 2 , wherein the first semiconductor region is in an electrically floating state.

4. The light detection device according to claim 1, wherein The semiconductor layer includes a second semiconductor region between the through hole and the first trench, and The second semiconductor region is in an electrically floating state.

5. The light detection device according to claim 1, wherein: The first groove is disposed outside the pad in a plan view.

6. The light detection device according to claim 1, comprising a second trench adjacent to the through hole and penetrating the semiconductor layer, in, The through hole includes a semiconductor region doped with impurities on a sidewall of the second trench.

7. The light detection device according to claim 1, comprising a second trench adjacent to the through hole and penetrating the semiconductor layer, in, The through hole includes a pinning film disposed on a sidewall of the second trench.

8. The light detection device according to claim 1, comprising a second trench provided with the through hole and penetrating the semiconductor layer, in, The via includes a metal material disposed in the second trench.

9. The light detection device according to claim 1, comprising The third trench is provided to penetrate the semiconductor layer between the adjacent plurality of photoelectric conversion portions and surround each of the plurality of photoelectric conversion portions.

10. The light detection device according to claim 9, wherein: The first grooves and the third grooves are formed with the same lattice shape in a plan view.

11. The light detection device according to claim 9, comprising a second trench adjacent to the through hole and penetrating the semiconductor layer, in, The second grooves and the third grooves are formed with the same lattice shape in a plan view.

12. The light detection device according to claim 9, comprising: a second trench adjacent to the through hole and penetrating the semiconductor layer; and Semiconductor regions are respectively disposed on the sidewalls of the second trench and the third trench and are doped with impurities.

13. The light detection device according to claim 9, comprising: a second trench adjacent to the through hole and penetrating the semiconductor layer; and A pinning film is disposed on a sidewall of the second trench and a sidewall of the third trench, respectively.

14. The light detection device according to claim 9, comprising a second trench provided with the through hole and penetrating the semiconductor layer, in, The second trench and the third trench are embedded with the same metal material.

15. The light detection device according to claim 1, wherein The light detection device has a back-side illumination structure.

16. The light detection device according to claim 1, comprising: A lens disposed on the first surface side of the semiconductor layer; and A wiring layer is provided on a second surface side of the semiconductor layer opposite to the first surface.

17. An electronic device comprising: Optical system; and a light detection device that receives light that passes through the optical system, Wherein, the light detection device comprises: a semiconductor layer including a plurality of photoelectric conversion sections that perform photoelectric conversion on light; a pad disposed on the first surface side of the semiconductor layer; a through hole penetrating the semiconductor layer and electrically connected to the pad; and A first trench is provided, which is arranged to penetrate the semiconductor layer around the through hole and surround the through hole, and In a plan view, the first grooves are arranged in a grid shape around the through hole.

Images