Light detection device, method for producing light detection device, and electronic apparatus

Abstract

A light detection device according to an embodiment of the present disclosure comprises: an optical layer having a plurality of structures provided so as to be lined up in a first direction; a first region that has a plurality of pixels each including a photoelectric conversion element that photoelectrically converts light incident through the optical layer; and a second region that has a first reflection member provided above the optical layer, the second region being provided around the first region.

Description

Photodetector, method for manufacturing photodetector, and electronic device

[0001] The present disclosure relates to a photodetector, a method for manufacturing a photodetector, and an electronic device.

[0002] An image sensor has been proposed that has a first lens layer including a plurality of nanoposts and a second lens layer including a plurality of nanoposts (Patent Document 1).

[0003] Japanese Patent Application Laid-Open No. 2022-74062

[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 an optical layer having a plurality of structures arranged in a first direction, a first region having a plurality of pixels each including a photoelectric conversion element that photoelectrically converts light incident through the optical layer, and a second region having a first reflecting member arranged above the optical layer and surrounding the first region. A method for manufacturing the photodetector according to an embodiment of the present disclosure includes preparing a semiconductor layer having a plurality of photoelectric conversion elements, forming a first member above the semiconductor layer, forming the first reflecting member above the first member in the second region surrounding the first region including the plurality of photoelectric conversion elements, forming a mask pattern on the first reflecting member, and forming a plurality of structures in the first region by removing a portion of the first member via the mask pattern. 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 device has an optical layer having a plurality of structures arranged in a first direction, a first region having a plurality of pixels each including a photoelectric conversion element that photoelectrically converts light incident through the optical layer, and a second region having a first reflective member arranged above the optical layer and arranged around the first region.

[0007] FIG. 1 is a block diagram showing an example of a schematic configuration of an imaging device, which is an example of a light detection device according to an embodiment of the present disclosure. FIG. 2 is a diagram showing an example of a planar configuration of an imaging device according to an embodiment of the present disclosure. FIG. 3 is a diagram showing an example of a circuit configuration of a pixel of an imaging device according to an embodiment of the present disclosure. FIG. 4 is a diagram for explaining an example of a planar configuration of an imaging device according to an embodiment of the present disclosure. FIG. 5 is a diagram showing an example of a cross-sectional configuration of an imaging device according to an embodiment of the present disclosure. FIG. 6 is a diagram for explaining an example of a configuration of an imaging device according to an embodiment of the present disclosure. FIG. 7 is a diagram for explaining an example of an arrangement of a pattern region of an imaging device according to an embodiment of the present disclosure. FIG. 8A is a diagram showing an example of a configuration of a pattern region of an imaging device according to an embodiment of the present disclosure. FIG. 8B is a diagram showing an example of a configuration of a pattern region of an imaging device according to an embodiment of the present disclosure. FIG. 9 is a diagram showing an example of a planar configuration of an imaging device according to an embodiment of the present disclosure. FIG. 10 is a diagram showing an example of a planar configuration of an imaging device according to an embodiment of the present disclosure. FIG. 11 is a diagram showing an example of a cross-sectional configuration of an imaging device according to an embodiment of the present disclosure. FIG. 12 is a diagram for explaining an example of a configuration of an imaging device according to an embodiment of the present disclosure. FIG. 13 is a diagram for explaining another example configuration of an imaging device according to an embodiment of the present disclosure. FIG. 14A is a diagram for explaining an example of a manufacturing method of an imaging device according to an embodiment of the present disclosure. FIG. 14B is a diagram for explaining an example of a manufacturing method of an imaging device according to an embodiment of the present disclosure. FIG. 14C is a diagram for explaining an example of a manufacturing method of an imaging device according to an embodiment of the present disclosure. FIG. 14D is a diagram for explaining an example of a manufacturing method of an imaging device according to an embodiment of the present disclosure. FIG. 14E is a diagram for explaining an example of a manufacturing method of an imaging device according to an embodiment of the present disclosure. FIG. 14F is a diagram for explaining an example of a configuration of an imaging device according to a first modification of the present disclosure. FIG. 16 is a block diagram showing an example of a configuration of an electronic device having an imaging device. FIG. 17 is a block diagram showing an example of a schematic configuration of a vehicle control system. FIG. 18 is an explanatory diagram showing an example of installation positions of an outside vehicle information detection unit and an imaging unit. FIG. 19 is a diagram for explaining an example of a schematic configuration of an endoscopic surgery system. FIG. 20 is a block diagram showing an example of a 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 image pickup device which is an example of a photodetection device according to an embodiment of the present disclosure. The photodetection device is a device capable of detecting incident light. The image pickup device 1 which is a photodetection device has a plurality of pixels P1 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 P1 are provided. The photoelectric conversion unit of each pixel P1 of the imaging device 1 is, for example, a photodiode (PD) that is configured to be able to photoelectrically convert light.

[0011] As an example, the imaging device 1 has an imaging area (pixel section 100) in which a plurality of pixels P1 are arranged two-dimensionally in a matrix, as shown in Fig. 1. The pixel section 100 of the imaging device 1 is a pixel array in which a plurality of pixels P1 are arranged, and can also be referred to as a light-receiving region. The photoelectric conversion section of each pixel P1 can also be referred to as a photoelectric conversion region. The pixel section 100 can include effective pixels, light-shielding pixels, etc.

[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, for example, 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 L1 and a plurality of signal lines L2.

[0015] The control line L1 is a signal line capable of transmitting a signal for controlling the pixel P1, and is connected to the pixel control unit 111 and the pixel P1 of the pixel unit 100. In the example shown in Fig. 1 , in the pixel unit 100, a plurality of control lines L1 are wired for each pixel row made up of a plurality of pixels P1 arranged in the horizontal direction (row direction). The control line L1 is configured to transmit a control signal for reading out a signal from the pixel P1.

[0016] The plurality of control lines L1 for each pixel row of the imaging device 1 include, for example, wiring for transmitting signals that control transfer transistors, wiring for transmitting signals that control selection transistors, wiring for transmitting signals that control reset transistors, etc. The control lines L1 can also be referred to as drive lines (pixel drive lines) that transmit signals that drive the pixels P1.

[0017] The signal line L2 is a signal line capable of transmitting a signal from the pixel P1, and is connected to the pixel P1 of the pixel unit 100 and the signal processing unit 112. In the pixel unit 100, for example, one or more signal lines L2 are wired for each pixel column made up of multiple pixels P1 lined up in the vertical direction (column direction). The signal line L2 is configured to be able to transmit a signal output from the pixel P1. In the imaging device 1, multiple signal lines L2 may be provided for one pixel column. The imaging device 1 may have multiple signal lines L2 for each pixel column.

[0018] The pixel control unit 111 is configured to be able to control each pixel P1 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 P1 and outputs it to each pixel P1 of the pixel unit 100 via a control line L1. The pixel control unit 111 is controlled by the control unit 113 and controls the pixel P1 of the pixel unit 100.

[0019] The pixel control unit 111 generates signals for controlling the pixel P1, such as a signal for controlling the transfer transistor, a signal for controlling the selection transistor, and a signal for controlling the reset transistor of the pixel P1, and supplies these signals to each pixel P1 via a control line L1. The pixel control unit 111 can also control the reading of pixel signals from each pixel P1. The pixel control unit 111 can also be referred to as a pixel driving unit configured to be able to drive each pixel P1. The pixel control unit 111 and the control unit 113 can also be referred to collectively as a pixel control unit.

[0020] 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 pixel P1. The load circuit, together with the amplification transistor of pixel P1, forms, for example, a source follower circuit.

[0021] The signal processing unit 112 may have an amplifier circuit configured to be able to amplify signals read from the pixels P1 via the signal lines L2. A load circuit, an amplifier circuit, an AD conversion circuit, etc. may be provided for each of the multiple signal lines L2. A load circuit, an amplifier circuit, an AD conversion circuit, etc. may be provided for each pixel column of the pixel unit 100.

[0022] The signals output from each pixel P1 selected and scanned by the pixel control unit 111 are input to the signal processing unit 112 via signal lines L2. The signal processing unit 112 can perform signal processing such as AD conversion of the signal from the pixel P1 and CDS (Correlated Double Sampling). The signals from each pixel P1 transmitted through each signal line L2 are subjected to signal processing by the signal processing unit 112 and output to the processing unit 114.

[0023] 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.

[0024] The control unit 113 is configured to be able to control each unit of the imaging device 1. The control unit 113 receives an externally provided clock, data instructing an 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.

[0025] The control unit 113 controls the driving of the pixel control unit 111, the signal processing unit 112, etc. based on various timing signals (pulse signals, clock signals, etc.) generated by the timing generator. The control unit 113 and the processing unit 114 may be configured integrally.

[0026] 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.

[0027] 2 is a diagram showing an example of the planar configuration of an imaging device according to an embodiment. The imaging device 1 has an area (referred to as an effective pixel area 101) in which a plurality of pixels P1 are provided, and an area (OPB (Optical Black) area 102) provided around the effective pixel area 101. The OPB area 102 can also be referred to as a light-shielding pixel area in which a plurality of light-shielding pixels are provided.

[0028] As shown in Fig. 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 in the figure, the pixel control unit 111, signal processing unit 112, control unit 113, processing unit 114, etc. described above may be provided in a peripheral region of the pixel unit 100, for example, as peripheral circuits.

[0029] Pixels P1 serving as effective pixels are two-dimensionally arranged in the effective pixel region 101. For example, a plurality of pixels P1 are provided in the effective pixel region 101 so as to be aligned in the horizontal direction (X-axis direction) and the vertical direction (Y-axis direction). The plurality of pixels P1 in the effective pixel region 101 include, for example, pixels (R pixels) having photoelectric conversion units that receive light in the red (R) wavelength region, pixels (G pixels) having photoelectric conversion units that receive light in the green (G) wavelength region, and pixels (B pixels) having photoelectric conversion units that receive light in the blue (B) wavelength region.

[0030] In the effective pixel region 101, for example, a plurality of R pixels, a plurality of G pixels, and a plurality of B pixels are repeatedly arranged. The R pixels, G pixels, and B pixels can generate R component pixel signals, G component pixel signals, and B component pixel signals, respectively. The imaging device 1 can obtain RGB pixel signals. The number and arrangement of pixels P1 in the effective pixel region 101 can be set arbitrarily.

[0031] 2, the OPB region 102 is provided so as to surround the effective pixel region 101. In the OPB region 102, cells P2 serving as light-shielding pixels are arranged two-dimensionally. In the OPB region 102, as an example, a plurality of cells P2 are arranged so as to surround the effective pixel region 101. The cells P2 have, for example, a light-shielding member (light-shielding film) above the photoelectric conversion unit, and are in a light-shielding state.

[0032] As will be described later, the OPB region 102 has a region (referred to as a pattern region 90) provided around the effective pixel region 101 (see FIGS. 5 and 7, etc.). The pattern region 90 can be provided adjacent to the effective pixel region 101 as a region available for measurement (e.g., OCD (Optical Critical Dimension)).

[0033] Light from a subject to be measured is incident on each pixel P1 in the effective pixel area 101. The pixel P1 receives the incident light and performs photoelectric conversion to generate a pixel signal. The imaging device 1 can generate image data representing the subject image using the pixel signal obtained by photoelectric conversion in each pixel P1.

[0034] 3 is a diagram showing an example of a circuit configuration of a pixel of an imaging device according to an embodiment. Pixel P1 has a photoelectric conversion unit 12 and a readout circuit 20. The photoelectric conversion unit 12 (photoelectric conversion element) is configured to receive light and generate a signal. The readout circuit 20 is configured to be able to output a signal based on the charge generated by photoelectric conversion.

[0035] 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. 3, 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.

[0036] The readout circuit 20 includes, for example, a transistor TRG, a floating diffusion FD, a transistor AMP, a transistor SEL, and a transistor RST. The readout circuit 20 can read out pixel signals based on charges photoelectrically converted by the photoelectric conversion unit 12.

[0037] The transistor TRG 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 TRG is controlled by a signal STRG to electrically connect or disconnect the photoelectric conversion unit 12 and the floating diffusion FD. The transistor TRG can transfer charges photoelectrically converted and accumulated in the photoelectric conversion unit 12 to the floating diffusion FD.

[0038] 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.

[0039] The transistor AMP is configured to generate and output a signal based on the charge accumulated in the floating diffusion FD. The transistor AMP is an amplifying transistor and can generate and output a signal based on the charge converted by the photoelectric conversion unit 12.

[0040] 3, the gate of the transistor AMP 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 AMP. The drain of the transistor AMP is connected to a power supply line that supplies a power supply voltage (power supply voltage VDD in the example shown in FIG. 3).

[0041] The source of the transistor AMP is connected to a signal line L2 via a transistor SEL. The transistor AMP is configured to generate a signal based on the charge accumulated 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 L2.

[0042] The transistor SEL is configured to be able to control the output of a pixel signal. The transistor SEL is electrically connected in series to the transistor AMP, for example, as in the example shown in FIG. 3. The transistor SEL is controlled by a signal SSEL and is configured to be able to output a signal from the transistor AMP to a signal line L2. The transistor SEL is a selection transistor and can control the output timing of the pixel signal.

[0043] The transistor SEL is configured to be able to output a signal based on the charge converted by the photoelectric conversion unit 12. The transistor SEL can output a pixel signal of the pixel P1 to a signal line L2. The transistor SEL may be electrically connected in series between the transistor AMP and a power supply line to which a power supply voltage (power supply voltage VDD in FIG. 3) is applied. The transistor SEL may also be omitted as necessary.

[0044] The transistor RST is configured to be able to reset the voltage of the floating diffusion FD. In the example shown in Fig. 3, the transistor RST 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 pixel P1. The transistor RST is a reset transistor.

[0045] The transistor RST is controlled by a signal SRST and can reset the charge accumulated in the floating diffusion FD and reset the voltage of the floating diffusion FD. The transistor RST electrically connects the power supply line and the floating diffusion FD and can discharge the charge accumulated in the floating diffusion FD. The transistor RST can also discharge the charge accumulated in the photoelectric conversion unit 12 via the transistor TRG.

[0046] The readout circuit 20 may be configured to change the conversion efficiency (gain) when converting electric charge into voltage. For example, the readout circuit 20 may include a transistor (switching transistor) used to set the conversion efficiency. As an example, the switching transistor is electrically connected between the floating diffusion FD and the transistor RST.

[0047] In the readout circuit 20, when the switching transistor is turned on, the capacitance added to the floating diffusion FD of the pixel P1 increases, and the conversion efficiency (gain) when converting charge to voltage is switched. The switching transistor can change the conversion efficiency by switching the capacitance connected to the gate of the transistor AMP.

[0048] The above-mentioned transistor TRG (transfer transistor), transistor AMP (amplification transistor), transistor SEL (selection transistor), transistor RST (reset transistor), and switching transistor are each a MOS transistor (MOSFET) having gate, source, and drain terminals.

[0049] 3, the transistors TRG, AMP, SEL, and RST are each configured as an NMOS transistor. The transistor of the pixel P1 may be configured as a PMOS transistor.

[0050] The pixel control unit 111 (see Figure 1) of the imaging device 1 supplies control signals to the gates of the transistor TRG, transistor SEL, transistor RST, switching transistor, etc. of each pixel P1 via the above-mentioned control line L1, turning the transistors on (conducting state) or off (non-conducting state).

[0051] The multiple control lines L1 for each pixel row of the imaging device 1 include, for example, a wiring for transmitting a signal STRG that controls the transistor TRG, a wiring for transmitting a signal SSEL that controls the transistor SEL, and a wiring for transmitting a signal SRST that controls the transistor RST.

[0052] The transistors TRG, SEL, RST, and switching transistors are controlled to be turned on and off by a pixel control unit 111. The pixel control unit 111 controls the readout circuit 20 of each pixel P1 to output a pixel signal from each pixel P1 to a signal line L2. The pixel control unit 111 can control the reading out of the pixel signal of each pixel P1 to the signal line L2.

[0053] The imaging device 1 may have a configuration in which a plurality of pixels P1 share one readout circuit 20. For example, in the imaging device 1, the readout circuit 20 may be provided for a plurality of pixels P1. A readout circuit 20 is arranged for each of the plurality of pixels P1, and the plurality of pixels P1 share one readout circuit 20.

[0054] As an example, a 2×2 pixel array consisting of four adjacent pixels P1 may share one readout circuit 20. Note that each cell P2 of the imaging device 1 has, for example, the same circuit elements (transistors TRG, AMP, etc.) as those of the pixel P1 described above. As an example, the cell P2 (light-shielded pixel) may have the same circuit configuration as the pixel P1 shown in FIG. 3.

[0055] [Configuration of Image Capturing Device] Fig. 4 is a diagram for explaining an example of the planar configuration of an image capturing device according to an embodiment. Fig. 4 shows an example of the arrangement of pixels P1 in a part of an effective pixel area 101 in the image capturing device 1. The pixel P1 of the image capturing device 1 has a light guiding section 60 configured using a structure 51.

[0056] The light guiding unit 60 has, for example, structures 51 and a member 55 provided around the structures 51. In the example shown in Fig. 4 , the light guiding unit 60 is configured to include a plurality of structures 51. The member 55 is, for example, a member arranged so as to fill the spaces between the plurality of adjacent structures 51, and can also be considered a filling member. The structure 51 can also be considered to be provided within the member 55 and to be arranged by replacing a part of the member 55.

[0057] The structures 51 are, for example, structures having a columnar (pillar-shaped) shape, and are pillars (columnar members). As an example, the structures 51 have a cylindrical shape. The structures 51 may also have a polygonal shape in a plan view. The shape of each structure 51 in the light-guiding section 60 can be changed as appropriate. Furthermore, the number and arrangement of the structures 51 are not limited to the example shown in the figure and can be changed as appropriate.

[0058] The light guide unit 60 has, for example, a plurality of structures 51 as nanostructures, and is configured to guide incident light toward the photoelectric conversion unit 12. The light guide unit 60 is a light guide element (light guide member) that uses metamaterial (metasurface) technology. In the imaging device 1, for example, as in the example shown in FIG. 4 , a light guide unit 60 is provided for each pixel P1 or for each set of multiple pixels P1.

[0059] The multiple pixels P1 in the effective pixel area 101 include, as an example, R pixels that receive and photoelectrically convert light mainly in the red wavelength range from the light from the subject to be measured, G pixels that receive and photoelectrically convert light mainly in the green wavelength range, and B pixels that receive and photoelectrically convert light mainly in the blue wavelength range.

[0060] As an example, the R, G, and B pixels are arranged according to a Bayer array. 2×2 pixels, each consisting of one R pixel, two G pixels, and one B pixel, are repeatedly arranged in the pixel unit 100. The pixel unit 100 has, for example, pixel rows in which G pixels and R pixels are alternately arranged, and pixel rows in which B pixels and G pixels are alternately arranged.

[0061] The R pixels, G pixels, and B pixels of the pixel unit 100 may each be arranged in 2×2 pixel units. For example, four adjacent R pixels, four adjacent G pixels, and four adjacent B pixels may be arranged repeatedly in the pixel unit 100. It can also be said that the R pixels, G pixels, and B pixels are each periodically arranged in 2 rows and 2 columns.

[0062] The pixel P1 of the pixel unit 100 may have a filter configured to selectively transmit light in a specific wavelength range from among incident light. The filter provided in the pixel P1 may be an RGB color filter, a complementary color filter, a filter that transmits infrared light, or the like. The filter is provided above the photoelectric conversion unit 12, for example, for each pixel P1 or for each set of multiple pixels P1.

[0063] 5 is a diagram showing an example of a cross-sectional configuration of an imaging device according to an embodiment. The imaging device 1 includes, for example, an optical layer 70, an insulating layer 80, a semiconductor layer 10, and a wiring layer 85. The imaging device 1 has a configuration in which the optical layer 70, the insulating layer 80, the semiconductor layer 10, and the wiring layer 85 are stacked in the Z-axis direction.

[0064] Arranged from the light incident side are an optical layer 70, an insulating layer 80, a semiconductor layer 10, and a wiring layer 85. The optical layer 70 has structures 51 and is configured to guide incident light toward the photoelectric conversion unit 12. The optical layer 70 has, for example, a plurality of structures 51 arranged side by side in the X-axis direction (or Y-axis direction).

[0065] The optical layer 70 is an optical element (optical member) that utilizes metamaterial (metasurface) technology. The structures 51 have, for example, a columnar shape and can be called a metasurface element. The optical layer 70 can also be called a metasurface layer (or metamaterial layer). In the example shown in FIG. 5 , the optical layer 70 including the structures 51 is stacked on an insulating layer 80.

[0066] The optical layer 70 includes structures 51 and members 55 provided around the structures 51. The structures 51 are, for example, pillars (columnar members) and can be referred to as nanopillars. The structures 51 and the members 55 are made of materials having different refractive indices. As in the example shown in FIG. 5 , the optical layer 70 can include a light guide section 60 including the structures 51 and the members 55 for each pixel P1 or for each of multiple pixels P1.

[0067] The semiconductor layer 10 is composed of a semiconductor substrate (for example, a Si (silicon) substrate, an SOI (silicon on insulator) substrate, etc.). The semiconductor layer 10 may be a SiGe (silicon germanium) substrate, a SiC (silicon carbide) substrate, etc., or may be formed using other semiconductor materials. The semiconductor layer 10 may also be composed of a III-V group compound semiconductor material, etc.

[0068] As shown in FIG. 5 , 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, for example, 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. may be provided on the surface 11S2 of the semiconductor layer 10.

[0069] 5 , an insulating layer 80 is provided on the surface 11S1 side of the semiconductor layer 10. The optical layer 70 and the insulating layer 80 are stacked on the semiconductor layer 10 in a thickness direction perpendicular to the surface 11S1 of the semiconductor layer 10. A wiring layer 85 is provided on the surface 11S2 side of the semiconductor layer 10. The optical layer 70 is provided on the side where light from the optical system is incident, and the wiring layer 85 is provided on the side opposite to the side where the light is incident.

[0070] In the semiconductor layer 10, a plurality of photoelectric conversion units 12 (photoelectric conversion elements) are provided along the surfaces 11S1 and 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 surfaces 11S1 and 11S2 of the semiconductor layer 10. The photoelectric conversion units 12 can also be referred to as a photoelectric conversion layer. The photoelectric conversion units 12 photoelectrically convert light incident via the optical layer 70 and the insulating layer 80.

[0071] The wiring layer 85 is provided by being stacked on the semiconductor layer 10. The wiring layer 85 includes, for example, a conductor film and an insulating film, and has a plurality of wires and vias (VIAs). The wiring layer 85 is a multi-layer wiring layer, and includes, for example, two or more layers of wires, or three or more layers of wires. The wiring layer 85 has a configuration in which a plurality of wires are stacked via an insulating film serving as an interlayer insulating film (interlayer insulating layer).

[0072] The wiring of the wiring layer 85 is formed using a metal material such as aluminum (Al), tungsten (W), copper (Cu), etc. The wiring of the wiring layer 85 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), etc.

[0073] For example, the above-described readout circuit 20 (see FIG. 3 ) is provided for each pixel P1 or for each set of multiple pixels P1 in the semiconductor layer 10 and the wiring layer 85. The above-described pixel control unit 111, signal processing unit 112, control unit 113, processing unit 114, etc. (see FIG. 1 ) may be provided on the semiconductor layer 10 and the wiring layer 85, or on a substrate separate from the semiconductor layer 10.

[0074] The insulating layer 80 is provided between the optical layer 70 having the light-guiding section 60 and the semiconductor layer 10. The insulating layer 80 is made of an insulating film such as an oxide film, a nitride film, or an oxynitride film. The insulating layer 80 may be made of an insulating material such as silicon oxide (SiO), silicon nitride (SiN), or aluminum oxide (AlO), or may be made of other materials.

[0075] The insulating layer 80 may be made of a material with a low refractive index, such as silicon oxide, or may be made of another material that transmits light in the wavelength range to be measured. The insulating layer 80 can also be called a transparent layer that transmits light, or a spacer layer. Note that the optical layer 70 may be configured to include the insulating layer 80.

[0076] As shown in FIG. 5 , the imaging device 1 has an isolation region 30, which is an isolation region (isolation section) provided around a pixel P1 (or a photoelectric conversion section 12). The isolation region 30 is provided between adjacent pixels P1 in the semiconductor layer 10, and separates the pixels P1 (or the photoelectric conversion sections 12). At least a portion of the isolation region 30 is provided at the boundary between adjacent pixels P1. The isolation region 30 is formed using, for example, a trench (groove section).

[0077] The isolation region 30 may be formed in a lattice pattern in the semiconductor layer 10 so as to surround the photoelectric conversion unit 12 of each pixel P1. The isolation region 30 may be provided so as to penetrate the semiconductor layer 10. That is, the isolation region 30 may be formed so as to reach the surface 11S2 of the semiconductor layer 10. The isolation region 30 may also be referred to as a pixel isolation portion or a pixel isolation wall.

[0078] An insulating film, such as a silicon oxide film, a silicon nitride film, a silicon oxynitride film, or an aluminum oxide film, is provided in the trench of the isolation region 30. Polysilicon, a metal material, or another insulating material may be buried in the trench of the isolation region 30. The isolation region 30 may be composed of a semiconductor region (a p-type semiconductor region or an n-type semiconductor region) formed by ion implantation.

[0079] The separation region 30 may be formed using other insulating materials having a low refractive index. A gap (cavity) may be provided within the separation region 30. The provision of the separation region 30 prevents the electric charge converted by the photoelectric conversion unit 12 of the pixel P1 from leaking to the surrounding pixels P1 (or the photoelectric conversion units 12). Furthermore, the separation region 30 prevents unnecessary light from leaking to the surrounding pixels P1, thereby preventing, for example, color mixing.

[0080] The imaging device 1 may have at least one of a fixed charge film and an antireflection film on the surface 11S1 side of the semiconductor layer 10. The fixed charge film and the antireflection film are, for example, made of a metal compound (metal oxide, metal nitride, etc.) and can also be called a metal compound layer.

[0081] A portion of each of the fixed charge film and the antireflection film may be provided in the semiconductor layer 10 along the sidewall (side surface) of the isolation region 30. The fixed charge film is a film having a fixed charge and may be formed using a high dielectric material. For example, the fixed charge film is made of a metal oxide such as aluminum oxide or hafnium oxide. The fixed charge film is, for example, a film having a negative fixed charge.

[0082] 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.

[0083] The antireflection film is made of, for example, a metal oxide such as hafnium oxide or tantalum oxide. The antireflection film (anti-reflection film) is provided on the surface 11S1 side of the semiconductor layer 10 to reduce (suppress) reflection. The antireflection film is provided, for example, so as to be stacked with the fixed charge film. The antireflection 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.

[0084] 5 , the optical layer 70 is provided above the photoelectric conversion unit 12. Light from a subject serving as a measurement target is incident on the light guiding unit 60. For example, light that has passed through an optical system such as an imaging lens is incident on the structures 51 of the light guiding unit 60. For example, the structures 51 are structures whose size is equal to or smaller than a predetermined wavelength of the incident light.

[0085] The light guide unit 60 (or the optical layer 70) has structures 51 which are nanostructures, and is configured to guide light incident from above in FIG. 5 toward the photoelectric conversion unit 12. The structures 51 have a size equal to or smaller than the wavelength range of light to be measured, for example, a size equal to or smaller than the wavelength range of visible light. The structures 51 may also have a size equal to or smaller than the wavelength range of infrared light.

[0086] The multiple structures 51 of the light-guiding unit 60 are arranged side by side in the X-axis direction (or Y-axis direction) with a part of the member 55 sandwiched between them. As described above, the structures 51 have, for example, a cylindrical shape. Note that the shape of the structures 51 can be changed as appropriate and may be a circle or a rectangle in a plan view. The shape of the structures 51 may be an ellipse, a polygon, a cross, or any other shape.

[0087] 5 , the member 55 is provided between adjacent structures 51. The member 55 may be formed so as to cover the structures 51. For example, a portion of the member 55 may be located on the structures 51. The member 55 is a member located around the structures 51, and may also be referred to as a support member or a material layer.

[0088] The light guide unit 60 uses the structure 51, which is a nanostructure, to propagate light toward the photoelectric conversion unit 12. The structure 51 is also called, for example, a nanopillar, a metaatom, a nanoatom, a nanopost, a metasurface structure, or a microstructure. The light guide unit 60 is an optical element (optical member) that guides (propagates) light.

[0089] The light-guiding unit 60 is configured as, for example, a light-guiding element that can impart a phase delay to incident light and guide the light. As an example, a plurality of structures 51 are formed in the optical layer 70 so as to impart a desired phase profile to the incident light. For example, the size, number of structures 51, arrangement interval (pitch), etc. are determined so that light in a wavelength band to be detected is focused onto the photoelectric conversion unit 12.

[0090] In the optical layer 70, for example, the plurality of structures 51 are arranged at intervals equal to or less than a predetermined wavelength of incident light. As an example, the plurality of structures 51 are provided in the X-axis direction and the Y-axis direction at intervals equal to or less than the wavelength range of visible light. Note that in the pixel P1, the plurality of structures 51 may be arranged at intervals equal to or less than the wavelength range of infrared light.

[0091] The structure 51 is configured to have a refractive index different from that of the adjacent medium. The structure 51 has a refractive index different from that of the medium surrounding the structure 51, i.e., the member 55. For example, the structure 51 has a refractive index higher than that of the member 55. The structure 51 and the member 55 may be made of different materials.

[0092] The structure 51 is made of, for example, a material having a refractive index higher than that of the member 55. The structure 51 is made of a high refractive index material and can also be called a high refractive index portion. The member 55 is made of a low refractive index material and can also be called a low refractive index portion. The member 55 can also be called a material layer having a refractive index different from that of the structure 51.

[0093] The structure 51 is formed of, for example, an oxide film containing titanium (Ti). As an example, the structure 51 is formed using titanium oxide (TiO). As another example, the structure 51 may be formed using silicon, polysilicon (Poly-Si), amorphous silicon (a-Si), germanium (Ge), or the like.

[0094] The structure 51 may be made of titanium (Ti), hafnium (Hf), aluminum (Al), zirconium (Zr), tantalum (Ta), indium (In), niobium (Nb), or the like, or an oxide, nitride, oxynitride, or a composite thereof.

[0095] The structure 51 may be made of other metal compounds (metal oxides, metal nitrides, etc.). The structure 51 may be made of GaP, GaN, GaAs, etc. The structure 51 may also be formed of silicon carbide (SiC) or other silicon compounds.

[0096] The member 55 is made of, for example, an inorganic material such as an oxide, a nitride, or an oxynitride. The member 55 may be made of, for example, silicon oxide (SiO), silicon nitride (SiN), or silicon oxynitride (SiON). The member 55 may also be made of silicon oxynitride, silicon carbide, silicon oxycarbide, silicon carbonitride, or other silicon compounds.

[0097] The member 55 may be made of, for example, a siloxane-based resin, a styrene-based resin, an acrylic-based resin, or the like. The member 55 may be made of a material in which any of these resins contains fluorine. The member 55 may be made of a material in which any of these resins is filled with beads (filler) having a refractive index higher (or lower) than that of the resin.

[0098] The materials constituting the structure 51 and the member 55 can be selected depending on the refractive index difference with the surrounding medium, the wavelength range of incident light to be measured, etc. The structure 51 and the member 55 may be made of an inorganic material or an organic material. Furthermore, the structure 51 or the member 55 may be made of a void (cavity). For example, the member 55 may be made to include air (void).

[0099] The light-guiding section 60 of the optical layer 70 can control the wavefront of the light by causing a phase delay in the incident light due to, for example, a difference in refractive index between the structures 51 and the medium surrounding them. The light-guiding section 60 can adjust the propagation direction of the light by, for example, imparting a phase delay to the incident light using the structures 51 and the members 55 surrounding the structures 51.

[0100] In each pixel P1 of the imaging device 1, for example, the effective refractive index of the light guide section 60 formed by the structures 51 and the members 55 is adjusted according to the occupancy rate (filling rate) of the structures 51, and the amount of phase delay of light in each wavelength range can be set. By adjusting the size and number of the structures 51, the amount of phase delay can be controlled, and a desired phase distribution can be realized.

[0101] The materials of the structures 51 and the members 55 (optical constants of each material), the size of the structures 51 (width (diameter), height, etc.), the pitch (arrangement interval), etc. are determined so that light of a desired wavelength range among the incident light from the measurement target travels in a desired direction. For example, the material (refractive index), dimensions, pitch, etc. of the structures 51 can be set.

[0102] For example, structures 51 of different sizes (width, height, cross-sectional area, etc.) may be provided in the optical layer 70 of the imaging device 1. As an example, structures 51 of different widths (diameters) may be provided in the light guide section 60 of each pixel P1 in order to obtain desired optical characteristics (for example, light refraction characteristics).

[0103] As an example, in the imaging device 1, the material, size, arrangement number, etc. of the structures 51 of each pixel P1 are determined so that light in a specific wavelength band to be detected travels to the photoelectric conversion unit 12 of the desired pixel P1. For example, the structures 51 of the light guide units 60 of the R pixel, G pixel, and B pixel may be formed so as to have different sizes (e.g., width, height), arrangement positions, etc.

[0104] The optical layer 70 (or the light guide unit 60) may be configured as, for example, a spectroscopic unit (spectroscopic element) capable of separating incident light. The optical layer 70 (or the light guide unit 60) may be configured as a splitter (color splitter) and may also be referred to as a color splitter layer or a wavelength separation layer. The optical layer 70 (or the light guide unit 60) may also be referred to as an optical element configured to redirect light.

[0105] As described above, light from a subject to be measured is incident on each pixel P1 of the imaging device 1 via the optical layer 70. Each pixel P1 can receive the light incident thereon via the structures 51 of the light-guiding section 60 and generate a pixel signal. The imaging device 1 can generate image data representing the subject image using the pixel signal obtained by photoelectric conversion in each pixel P1.

[0106] Furthermore, the imaging device 1 can generate image data (distance image data) relating to the distance to an object, for example, using the pixel signal of each pixel. In this embodiment, the light guide unit 60 having the structure 51 can appropriately guide light to the photoelectric conversion unit 12. The metasurface element can efficiently guide light in any wavelength range to the photoelectric conversion unit 12.

[0107] 5 , the imaging device 1 is provided with a pattern region 90. The pattern region 90 is provided around the effective pixel region 101 and has a reflective member 40 provided above the optical layer 70. In the example shown in FIG. 5 , the reflective member 40 is formed on the optical layer 70 in the OPB region 102. The pattern region 90 is formed in the OPB region 102 and can be located near the pixel P1 in the effective pixel region 101.

[0108] The pattern region 90 has the reflective member 40 and is provided as a region that can be used for measurements to confirm the three-dimensional shape of the structure 51, the size of the structure 51, etc. The pattern region 90 can be formed as a region that can be used for process management. The pattern region 90 is configured as, for example, a region for OCD.

[0109] The pattern region 90 has a member 50 and a reflective member 40 provided above the member 50. The member 50 can be made of the same material as the structures 51 of the light-guiding section 60. The member 50 is, for example, a layer (film) formed in the effective pixel region 101 and the OPB region 102 as a constituent material of the structures 51 during the manufacturing process. The member 50 is, for example, made of the same high refractive index material as the structures 51, and can also be called a high refractive index section.

[0110] The reflective member 40 is a reflective portion (reflective film) made of a material that reflects light, and is provided on the member 50. The reflective member 40 is made of a material that reflects light, and reflects incident light. For example, the reflectance of the reflective member 40 for visible light may be 50% or more. Also, the reflectance of the reflective member 40 for infrared light may be 50% or more.

[0111] The reflective member 40 is located above the member 50 in the direction of light incidence. The reflective member 40 is provided so as to be laminated on the member 50. The reflective member 40 may be formed so as to cover the entire surface of the member 50. As an example, the reflective member 40 is made of tungsten (W). However, the reflective member 40 may also be made of other materials having high reflectivity. The reflective member 40 may also be made of a laminated film in which multiple films are laminated.

[0112] The reflecting member 40 may be made of a metal material such as aluminum (Al), magnesium (Mg), or silver (Ag). The reflecting member 40 may also be made of an Al compound or an Ag compound. The reflecting member 40 may be made of a material in which Al is mixed with copper (Cu), AlO ２ , or may be formed using other materials.

[0113] 5 , the imaging device 1 is provided with a light-shielding member 45. The light-shielding member 45 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. The light-shielding member 45 can be provided over the entire OPB region 102, including the pattern region 90.

[0114] The light-shielding member 45 is formed so as to cover the entire OPB region 102. For example, the light-shielding member 45 is provided so as to cover the photoelectric conversion units 12 of all the cells P2 arranged in the OPB region 102. The light-shielding member 45 is made of, for example, a metal material (aluminum, tungsten, copper, etc.) that blocks light. The light-shielding member 45 may be made of a laminated film in which a plurality of films are stacked.

[0115] Cell P2 is a pixel shielded by the light-shielding member 45 and can output a pixel signal indicating a reference level. Cell P2 generates and outputs, for example, a pixel signal indicating a reference level relative to the pixel signal of pixel P1, which is an effective pixel. The pixel signal generated by cell P2 can be said to be a signal indicating a black level (or offset level).

[0116] 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 the pixel signal generated by pixel P1 using the pixel signal generated by cell P2. For example, the processing unit 114 can perform subtraction processing between the pixel signal of pixel P1 and the pixel signal of cell P2 to generate a pixel signal in which noise components (e.g., dark current components) have been reduced. Note that this correction processing may be performed by the signal processing unit 112 of the imaging device 1.

[0117] As described above, the imaging device 1 according to this embodiment has the pattern area 90 that can be used for measurement. The pattern area 90 has the reflective member 40 and is provided around the effective pixel area 101. For example, by performing OCD measurement using the pattern area 90 in the manufacturing process, it becomes possible to estimate whether the structures 51 of the light guiding section 60 are properly formed.

[0118] 6 is a diagram illustrating an example of the configuration of an imaging device according to an embodiment. Fig. 6 illustrates a member 50 as a constituent member of a structure 51 and a mask pattern 120 formed on the member 50. The mask pattern 120 is, for example, a resist film pattern, a hard mask pattern, or the like. Also, Fig. 6 uses arrows to schematically indicate incident light from a measurement device that performs OCD measurement and reflected light reflected from a pattern region 90.

[0119] By analyzing the light reflected from the mask pattern 120 formed by lithography and etching, it is possible to obtain information about the three-dimensional shape of the mask pattern 120. By checking the shape, size, etc. of the mask pattern 120, it is possible to estimate whether the structures 51 of the light guiding section 60 are properly processed, and to perform management during manufacturing.

[0120] For example, if the size, positional deviation, etc. of the mask pattern 120 are outside the range of allowable values, the process of forming the mask pattern 120, etc. can be performed again to form the structure 51 having the desired three-dimensional structure. It is therefore possible to realize the light guide section 60 (optical layer 70) having good optical properties.

[0121] In this embodiment, the pattern region 90 is disposed in a region (for example, the OPB region 102) close to the effective pixel region 101. A reflective member 40 is provided directly below the mask pattern 120, which is the pattern to be measured. This allows stable reflected light to be obtained from the pattern region 90, which is the measurement pattern, making it possible to perform OCD measurement with high precision. This allows the three-dimensional shape of the structure 51 to be measured with high precision.

[0122] By utilizing the pattern region 90 provided in the vicinity of the effective pixel region 101, it is possible to grasp the shape, size, position, etc. of the structures 51 formed in the effective pixel region 101, and it becomes possible to appropriately manage the process. It is possible to estimate the shape of the structures 51 with high accuracy and form a high-quality device.

[0123] 7 is a diagram illustrating an example of the arrangement of pattern areas in an imaging device according to an embodiment. In the imaging device 1, for example, a plurality of pattern areas 90 are provided in the OPB area 102. The plurality of pattern areas 90 may be discretely arranged along the periphery of the effective pixel area 101. In the imaging device 1, the plurality of pattern areas 90 may be arranged side by side in the X-axis direction or the Y-axis direction.

[0124] The pattern region 90 (or the reflective member 40) has a size of, for example, 10 μm or more. The pattern region 90 (or the reflective member 40) may have a width of 50 μm or more in the X-axis direction (or Y-axis direction). For example, as shown in FIG. 7 , the width W1 of the pattern region 90 in the X-axis direction may be 10 μm or more. Furthermore, the width W2 of the pattern region 90 in the Y-axis direction may be 10 μm or more.

[0125] 8A and 8B are diagrams showing configuration examples of a pattern area of ​​an imaging device according to an embodiment. The pattern area 90 has a mask pattern 120 including one or more structures 125, as in the examples shown in Fig. 8A or 8B. The mask pattern 120 may be a mark formed using a plurality of structures 125 arranged in the X-axis direction or the Y-axis direction.

[0126] 8A or 8B , the mask pattern 120 may be a pattern (mark) having a plurality of structures 125 aligned in the X-axis direction and a plurality of structures 125 aligned in the Y-axis direction. As an example, the mask pattern 120 is configured using a plurality of structures 125 each having a cylindrical shape. In the pattern region 90, structures 125 of different sizes (width, cross-sectional area, etc.) may be provided.

[0127] Although the above describes an example of the configuration of the pattern region 90, this is merely an example, and the configuration of the pattern region 90 is not limited to the above example. For example, the shape and number of the structures 125 are not limited to the illustrated example, and can be set arbitrarily. The structures 125 may have a polygonal or circular shape in a plan view.

[0128] 9 and 10 are diagrams showing an example of the planar configuration of an imaging device according to an embodiment. The pattern region 90 may be provided so as to surround the effective pixel region 101, for example, as in the example shown in FIG. 9 . In the example shown in FIG. 9 etc., the imaging device 1 has an area where a scribe line is formed (referred to as a scribe region 107). The pattern region 90 may be provided between the effective pixel region 101 and the scribe region 107, as in the example shown in FIG. 9 etc.

[0129] 10 , the imaging device 1 may have, within the OPB area 102, a pattern area 90 having a reflective member 40 and an area (referred to as a pattern area 95) not having the reflective member 40. Each of the pattern area 90 and the pattern area 95 is formed in the OPB area 102 and is located between the effective pixel area 101 and the scribe area 107.

[0130] 11 is a diagram showing an example of a cross-sectional configuration of an imaging device according to an embodiment. The pattern region 95 of the imaging device 1 may have a light-shielding member 45 made of a light-reflecting material as the reflective member 41. The reflectance of the reflective member 41 with respect to incident light (visible light, infrared light, etc.) may be, for example, 50% or more.

[0131] The reflective member 41 (light-shielding member 45) is made of a metal material such as tungsten or aluminum. The reflective member 41 may be made of other materials. The pattern region 95 having the reflective member 41 can be provided around the effective pixel region 101 as an area available for measurement, as in the example shown in FIG. 10 .

[0132] 12 , OCD measurement can be performed using a pattern region 95 having a reflective member 41, making it possible to estimate whether or not the structures 51 of the light guiding unit 60 have been properly formed. By analyzing the light reflected from the pattern region 95, information regarding the three-dimensional shape of the structures 51 can be obtained. It is possible to determine whether or not the structures 51 of the light guiding unit 60 have been properly processed, and to perform process management.

[0133] For example, if the size, positional deviation, etc. of the structures 51 in the pattern region 95 are outside the range of allowable values, it is possible to perform the process of forming the optical layer 70 again to form the structures 51 having the desired three-dimensional structure. It is possible to realize the light guide section 60 (optical layer 70) having good optical properties.

[0134] In the imaging device 1 according to the present embodiment, the pattern area 95 is provided in the OPB area 102 and can be located in the vicinity of the effective pixel area 101. OCD measurement can be performed using light reflected from the pattern area 95 around the effective pixel area 101, making it possible to perform appropriate process management.

[0135] Fig. 13 is a diagram for explaining another example configuration of an imaging device according to an embodiment. As in the example shown in Fig. 13, the imaging device 1 may have a plurality of pattern areas 90 (pattern area 90a and pattern area 90b in Fig. 13). The imaging device 1 may also have a plurality of pattern areas 95 (pattern area 95a and pattern area 95b in Fig. 13). The number and arrangement of the pattern areas 90 and 95 are not limited to the example shown in the figure and can be changed as appropriate.

[0136] 14A to 14F are diagrams showing an example of a method for manufacturing an imaging device according to an embodiment. First, as shown in Fig. 14A, an insulating layer 80 including a light-shielding member 45 is formed on a semiconductor layer 10 in which a photoelectric conversion section 12, an isolation region 30, etc. are formed. Then, as shown in Fig. 14B, a member 50 serving as a high refractive index section made of a highly refractive material is formed on the insulating layer 80.

[0137] Next, as shown in Fig. 14C, a reflective member 40 is formed on the member 50 in the pattern region 90. Then, as shown in Fig. 14D, a mask pattern 120 (e.g., a resist film) is formed on the reflective member 40 by lithography and etching. After the mask pattern 120 is formed, OCD measurement is performed on the mask pattern 120 in the pattern region 90.

[0138] Then, based on the OCD measurement result, it is determined whether or not to form the mask pattern 120 again. As an example, if the size of the mask pattern 120 is not within the tolerance, the process of forming the mask pattern 120 is performed again. If the size of the mask pattern 120 is within the tolerance, the process proceeds to the next step.

[0139] Next, the member 50 is partially removed by etching (e.g., dry etching) through the mask pattern 120, thereby forming a plurality of structures 51 of the light guiding section 60 as shown in Fig. 14E. Then, as shown in Fig. 14F, a member 55 is formed around the structures 51. The imaging device 1 shown in Fig. 5 and the like can be manufactured by the manufacturing method described above. Note that the manufacturing method for the imaging device described above is merely an example, and other manufacturing methods may also be used.

[0140] [Actions and Effects] The photodetector according to this embodiment includes an optical layer (optical layer 70) having a plurality of structures (structures 51) arranged in a first direction (e.g., the X-axis direction), a first region (effective pixel region 101) having a plurality of pixels (pixels P1) each including a photoelectric conversion element (photoelectric conversion unit 12) that photoelectrically converts light incident through the optical layer, and a second region (pattern region 90) having a first reflective member (reflective member 40) arranged above the optical layer and arranged around the first region.

[0141] The photodetector (image capture device 1) according to this embodiment has a reflective member 40 provided above the optical layer 70, and a pattern region 90 provided around the effective pixel region 101. This makes it possible to perform process management using the pattern region 90. It is possible to realize a photodetector that can suppress deterioration in quality.

[0142] The photodetector (imaging device 1) according to this embodiment has a second reflecting member (reflecting member 41) provided below the optical layer, and further includes a third region (pattern region 95) provided around the first region. This makes it possible to perform process management using the pattern region 95. This makes it possible to realize a photodetector that can suppress quality degradation.

[0143] 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.

[0144] 2. Modifications (2-1. Modification 1) FIG. 15 is a diagram for explaining a configuration example of an imaging device according to Modification 1 of the present disclosure. As shown in FIG. 15 , the imaging device 1 may have an area (referred to as a pad area 106) in which pads 116 are provided. For example, a plurality of pad areas 106 are provided around the pixel unit 100. The pad area 106 includes a plurality of pads 116 and may be provided in the peripheral area of ​​the pixel unit 100.

[0145] The pad area 106 includes, for example, pads (terminals) used for transmitting signals to and from the outside. The pad area 106 includes input / output pads for inputting and outputting signals, input pads for inputting signals from outside the imaging device 1, output pads for outputting signals to the outside of the imaging device 1, etc. The pad area 106 also includes power supply pads, GND (ground) pads, etc.

[0146] 15 , the pattern region 90 may be provided in the pad region 106. The pattern region 90 may be provided, for example, between a plurality of adjacent pads 116. It can also be said that the pattern region 90 is formed by replacing a portion of the pad region 106.

[0147] (2-2. Modification 2) In the above-described embodiment and modification, configuration examples of the light detection device have been described, but the configuration of the light detection device (imaging device) is not limited to the above-described examples. For example, the imaging device 1 may have a layered structure in which two or three or more optical layers are stacked. The light guide section 60 of the optical layer 70 may be configured to include, for example, two or more stages of structures 51 or three or more stages.

[0148] 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. 16 shows a schematic configuration of an electronic device 1000.

[0149] 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.

[0150] 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.

[0151] 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.

[0152] 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.

[0153] 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.

[0154] 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.

[0155] FIG. 17 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.

[0156] The vehicle control system 12000 includes a plurality of electronic control units connected via a communication network 12001. In the example shown in Fig. 17, 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.

[0157] 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.

[0158] 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.

[0159] 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.

[0160] 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.

[0161] 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.

[0162] 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 distance between vehicles, maintaining vehicle speed, vehicle collision warning, vehicle lane departure warning, etc.

[0163] 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.

[0164] 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.

[0165] 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 the passengers of the vehicle or the outside of the vehicle of information. In the example of Fig. 17, 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.

[0166] FIG. 18 is a diagram showing an example of the installation position of the imaging unit 12031.

[0167] In FIG. 18, the imaging unit 12031 includes imaging units 12101, 12102, 12103, 12104, and 12105.

[0168] 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 imaging unit 12105 provided on the top of the windshield inside the vehicle cabin is mainly used to detect preceding vehicles, pedestrians, obstacles, traffic lights, traffic signs, lanes, etc.

[0169] 18 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.

[0170] 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.

[0171] 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 allows the vehicle to travel autonomously without relying on driver operation.

[0172] 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.

[0173] 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.

[0174] 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.

[0175] (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.

[0176] FIG. 19 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.

[0177] 19 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.

[0178] 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.

[0179] 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.

[0180] 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.

[0181] 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.

[0182] 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.

[0183] 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.

[0184] 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.

[0185] 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.

[0186] 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.

[0187] 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.

[0188] 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.

[0189] FIG. 20 is a block diagram showing an example of the functional configuration of the camera head 11102 and the CCU 11201 shown in FIG.

[0190] 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.

[0191] 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.

[0192] 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.

[0193] 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.

[0194] 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.

[0195] 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.

[0196] 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.

[0197] 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.

[0198] 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 .

[0199] 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.

[0200] 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.

[0201] The image processing unit 11412 performs various image processing operations on the image signal, which is RAW data transmitted from the camera head 11102 .

[0202] 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.

[0203] 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.

[0204] 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.

[0205] 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.

[0206] 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.

[0207] Although the present disclosure has been described above by way of embodiments, modifications, application examples, and applied examples, the present technology is not limited to the above-described embodiments, etc., and various modifications are possible. For example, although the modifications described above have been described as modifications of the above-described embodiments, the configurations of the modifications can be combined as appropriate.

[0208] In the above embodiments, an imaging device has been described as an example. However, 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. Note that the present disclosure is not limited to a back-illuminated image sensor, but may also be applied to a front-illuminated image sensor.

[0209] The photodetector according to the present disclosure may also be applied as a distance measuring sensor capable of measuring distances using a time-of-flight (TOF) method. The light receiving element (photoelectric conversion unit) of each pixel may be an avalanche photodiode (APD). The light receiving element may be configured, for example, by a single-photon avalanche diode (SPAD). The photodetector (image capture device) may also be applied as a sensor capable of detecting events, for example, an event-driven sensor (also known as an event vision sensor (EVS), event-driven sensor (EDS), dynamic vision sensor (DVS), etc.).

[0210] According to an embodiment of the present disclosure, a photodetector includes an optical layer having a plurality of structures aligned in a first direction, a first region having a plurality of pixels each including a photoelectric conversion element that photoelectrically converts light incident through the optical layer, and a second region having a first reflecting member provided above the optical layer and provided around the first region, thereby making it possible to realize a photodetector that can suppress deterioration in quality.

[0211] 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 comprising: an optical layer having a plurality of structures arranged in a first direction; a first region having a plurality of pixels, each including a photoelectric conversion element that photoelectrically converts light incident through the optical layer; and a second region having a first reflecting member arranged above the optical layer and arranged around the first region. (2) The photodetector described in (1) above further comprises a first member arranged in the optical layer in the second region and made of the same material as the structures. (3) The photodetector described in (1) or (2) above, in which the optical layer has a second member arranged around the structures in the first region, and the second member has a refractive index different from that of the structures. (4) The photodetector described in any one of (1) to (3), in which the second region is arranged to surround the first region. (5) The photodetector according to any one of (1) to (4), wherein a plurality of the second regions are provided around the first region in a planar view. (6) The photodetector according to any one of (1) to (5), wherein the second region is provided between the first region and a region where a scribe line is formed. (7) The photodetector according to any one of (1) to (6), wherein the reflectance of the first reflective member for visible light or infrared light is 50% or more. (8) The photodetector according to any one of (1) to (7), wherein the first reflective member is made of a metal material. (9) The photodetector according to any one of (1) to (8), wherein the second region has a width of 10 μm or more. (10) The photodetector according to any one of (1) to (9), wherein the photodetector further includes a second reflective member provided below the optical layer and a third region provided around the first region. (11) The light detection device according to (10), wherein the plurality of structures are provided in the optical layer in the first region and the third region.(12) The photodetector according to any one of (1) to (11), wherein the structures have a size equal to or smaller than the wavelength range of visible light or the wavelength range of infrared light. (13) A method for manufacturing a photodetector, comprising: preparing a semiconductor layer having a plurality of photoelectric conversion elements; forming a first member above the semiconductor layer; forming a first reflecting member above the first member in a second region surrounding the first region including the plurality of photoelectric conversion elements; forming a mask pattern on the first reflecting member; and forming a plurality of structures in the first region by removing a portion of the first member via the mask pattern. (14) The method for manufacturing a photodetector according to (13), wherein, after measuring the mask pattern in the second region, the plurality of structures are formed in the first region by removing a portion of the first member. (15) The method for manufacturing a photodetector according to (13) or (14), further comprising forming a second member having a refractive index different from that of the structures around the structures in the first region. (16) An electronic device comprising: an optical system; and a photodetector that receives light that has passed through the optical system, wherein the photodetector has: an optical layer having a plurality of structures arranged in a first direction; a first region having a plurality of pixels each including a photoelectric conversion element that photoelectrically converts light that is incident through the optical layer; and a second region having a first reflecting member arranged above the optical layer and arranged around the first region.

[0212] This application claims priority based on Japanese Patent Application No. 2024-051039, filed on March 27, 2024, in the Japan Patent Office, the entire contents of which are incorporated herein by reference.

[0213] 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: an optical layer having a plurality of structures arranged in a first direction; a first region having a plurality of pixels each including a photoelectric conversion element that photoelectrically converts light incident through the optical layer; and a second region having a first reflecting member arranged above the optical layer and arranged around the first region.

2. The photodetector according to claim 1, further comprising a first member provided on the optical layer in the second region and made of the same material as the structure.

3. The photodetector according to claim 1, wherein the optical layer has a second member provided around the structure in the first region, and the second member has a refractive index different from that of the structure.

4. The photodetector according to claim 1, wherein the second region is provided so as to surround the first region.

5. The photodetector according to claim 1, wherein, in a plan view, a plurality of the second regions are provided around the first region.

6. The photodetector according to claim 1, wherein the second region is provided between the first region and a region where a scribe line is formed.

7. The photodetector according to claim 1, wherein the reflectance of the first reflecting member for visible light or infrared light is 50% or more.

8. The photodetector according to claim 1, wherein the first reflecting member is made of a metal material.

9. The photodetector according to claim 1, wherein the second region has a width of 10 μm or more.

10. The photodetector according to claim 1, further comprising a second reflecting member provided below the optical layer and a third region provided around the first region.

11. The photodetector device according to claim 10, wherein a plurality of said structures are provided on said optical layer in said first region and said third region.

12. The photodetector according to claim 1, wherein the structure has a size equal to or smaller than the wavelength range of visible light or the wavelength range of infrared light.

13. A method for manufacturing a photodetector, comprising: preparing a semiconductor layer having a plurality of photoelectric conversion elements; forming a first member above the semiconductor layer; forming a first reflecting member above the first member in a second region surrounding the first region including the plurality of photoelectric conversion elements; forming a mask pattern on top of the first reflecting member; and forming a plurality of structures in the first region by removing portions of the first member via the mask pattern.

14. The method for manufacturing a photodetector according to claim 13, wherein after measurement of the mask pattern in the second region is performed, a plurality of structures are formed in the first region by removing a portion of the first member.

15. The method for manufacturing a photodetector according to claim 13, further comprising forming a second member having a refractive index different from that of the structure around the structure in the first region.

16. An electronic device comprising: an optical system; and a photodetector that receives light that has passed through the optical system, wherein the photodetector has: an optical layer having a plurality of structures arranged in a first direction; a first region having a plurality of pixels each including a photoelectric conversion element that photoelectrically converts light that has entered through the optical layer; and a second region having a first reflecting member arranged above the optical layer and arranged around the first region.

Images