Light detection apparatus and electronic device

Abstract

A light detection apparatus according to an embodiment of the present disclosure comprises a semiconductor layer, a first pixel that has second photoelectric conversion region and a first photoelectric conversion region provided to the semiconductor layer, and an optical layer that is provided above the semiconductor layer and that has a plurality of first structures. The optical layer includes a first region that corresponds to the first photoelectric conversion region and a second region that corresponds to the second photoelectric conversion region. The optical layer condenses, to the first photoelectric conversion region, light of a first wavelength band that enters the first region and condenses, to the second photoelectric conversion region, light of a the first wavelength band that enters the second region.

Description

Photodetector and electronic equipment

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

[0002] An image sensor has been proposed that includes a color separation lens array having a green light focusing region that focuses green light, and a spacer layer having a thickness that is half the focal length of the green light focusing region, and that focuses green light in the green light focusing region (Patent Document 1).

[0003] Japanese Patent Application Laid-Open No. 2022-74120

[0004] In a light-sensing device, it is desirable to suppress a decrease in resolution.

[0005] It is desirable to provide a photodetector that can suppress a decrease in resolution.

[0006] A photodetector according to an embodiment of the present disclosure includes a semiconductor layer, a first pixel having a first photoelectric conversion region and a second photoelectric conversion region provided in the semiconductor layer, and an optical layer provided above the semiconductor layer and having a plurality of first structures. The optical layer includes a first region corresponding to the first photoelectric conversion region and a second region corresponding to the second photoelectric conversion region. The optical layer focuses light of a first wavelength band incident on the first region to the first photoelectric conversion region, and focuses light of the first wavelength band incident on the second region to the second photoelectric conversion region. An electronic device according to an embodiment of the present disclosure includes an optical system and a photodetector that receives light transmitted through the optical system. The photodetector includes a semiconductor layer, a first pixel having a first photoelectric conversion region and a second photoelectric conversion region provided in the semiconductor layer, and an optical layer provided above the semiconductor layer and having a plurality of first structures. The optical layer includes a first region corresponding to the first photoelectric conversion region and a second region corresponding to the second photoelectric conversion region. The optical layer focuses light of a first wavelength band incident on the first region onto the first photoelectric conversion region, and focuses light of the first wavelength band incident on the second region onto the second photoelectric conversion region.

[0007] FIG. 1 is a block diagram illustrating 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 illustrating an example of a pixel unit of an imaging device according to an embodiment of the present disclosure. FIG. 3A is a diagram illustrating an example of a planar configuration of an imaging device according to an embodiment of the present disclosure. FIG. 3B is a diagram illustrating an example of a planar configuration of an imaging device according to an embodiment of the present disclosure. FIG. 4 is a diagram illustrating an example of a circuit configuration of a pixel of an imaging device according to an embodiment of the present disclosure. FIG. 5 is a diagram illustrating an example of a cross-sectional configuration of an imaging device according to an embodiment of the present disclosure. FIG. 6 is a diagram illustrating an example of a cross-sectional configuration of an imaging device according to an embodiment of the present disclosure. FIG. 7 is a diagram illustrating an example of a cross-sectional configuration of an imaging device according to an embodiment of the present disclosure. FIG. 8A is a diagram illustrating an example of a configuration of an imaging device according to an embodiment of the present disclosure. FIG. 8B is a diagram illustrating an example of a configuration of an imaging device according to an embodiment of the present disclosure. FIG. 9A is a diagram illustrating an example of a configuration of an imaging device according to an embodiment of the present disclosure. FIG. 9B is a diagram illustrating an example of a configuration of an imaging device according to an embodiment of the present disclosure. FIG. 10A is a diagram illustrating an example of a configuration of an imaging device according to an embodiment of the present disclosure. FIG. 10B is a diagram illustrating an example configuration of an imaging device according to an embodiment of the present disclosure. FIG. 11A is a diagram illustrating an example configuration of an imaging device according to an embodiment of the present disclosure. FIG. 11B is a diagram illustrating an example configuration of an imaging device according to an embodiment of the present disclosure. FIG. 12 is a diagram illustrating an example configuration of an optical layer of an imaging device according to an embodiment of the present disclosure. FIG. 13A is a diagram illustrating an example configuration of an imaging device according to an embodiment of the present disclosure. FIG. 13B is a diagram illustrating an example configuration of an imaging device according to an embodiment of the present disclosure. FIG. 13C is a diagram illustrating an example configuration of an imaging device according to an embodiment of the present disclosure. FIG. 13D is a diagram illustrating an example configuration of an imaging device according to an embodiment of the present disclosure. FIG. 13E is a diagram illustrating an example configuration of an imaging device according to an embodiment of the present disclosure. FIG. 14 is a diagram illustrating an example configuration of an imaging device according to Modification 1 of the present disclosure. FIG. 15 is a diagram illustrating an example configuration of an imaging device according to Modification 2 of the present disclosure. FIG. 16 is a diagram illustrating an example configuration of an imaging device according to Modification 2 of the present disclosure.FIG. 17 is a diagram for describing an example configuration of an imaging device according to Modification 3 of the present disclosure. FIG. 18A is a diagram for describing an example configuration of an imaging device according to Modification 3 of the present disclosure. FIG. 18B is a diagram for describing an example configuration of an imaging device according to Modification 3 of the present disclosure. FIG. 19 is a diagram for describing another example configuration of an imaging device according to Modification 3 of the present disclosure. FIG. 20A is a diagram for describing another example configuration of an imaging device according to Modification 3 of the present disclosure. FIG. 20B is a diagram for describing another example configuration of an imaging device according to Modification 3 of the present disclosure. FIG. 20C is a diagram for describing another example configuration of an imaging device according to Modification 3 of the present disclosure. FIG. 21 is a diagram for describing another example configuration of an imaging device according to Modification 3 of the present disclosure. FIG. 22 is a diagram for describing another example configuration of an imaging device according to Modification 3 of the present disclosure. FIG. 23A is a diagram for describing an example configuration of an imaging device according to Modification 4 of the present disclosure. FIG. 23B is a diagram for describing an example configuration of an imaging device according to Modification 4 of the present disclosure. FIG. 24 is a diagram for describing an example configuration of an imaging device according to Modification 5 of the present disclosure. FIG. 25A is a diagram illustrating an example configuration of an imaging device according to Modification 5 of the present disclosure. FIG. 25B is a diagram illustrating an example configuration of an imaging device according to Modification 5 of the present disclosure. FIG. 26A is a diagram illustrating an example configuration of an imaging device according to Modification 5 of the present disclosure. FIG. 26B is a diagram illustrating an example configuration of an imaging device according to Modification 5 of the present disclosure. FIG. 26C is a diagram illustrating an example configuration of an imaging device according to Modification 5 of the present disclosure. FIG. 27 is a diagram illustrating an example configuration of an imaging device according to Modification 6 of the present disclosure. FIG. 28 is a diagram illustrating another example configuration of an imaging device according to Modification 6 of the present disclosure. FIG. 29A is a diagram illustrating an example configuration of an imaging device according to Modification 7 of the present disclosure. FIG. 29B is a diagram illustrating an example configuration of an imaging device according to Modification 7 of the present disclosure. FIG. 30 is a diagram illustrating an example configuration of an imaging device according to Modification 8 of the present disclosure. FIG. 31A is a diagram illustrating an example configuration of an imaging device according to Modification 9 of the present disclosure. FIG. 31B is a diagram illustrating an example configuration of an imaging device according to Modification 9 of the present disclosure. Fig. 32 is a block diagram showing an example of the configuration of an electronic device having an imaging device, and Fig. 33 is a block diagram showing an example of the schematic configuration of a vehicle control system.Fig. 34 is an explanatory diagram showing an example of the installation positions of the vehicle outside information detection unit and the imaging unit. Fig. 35 is a diagram showing an example of the schematic configuration of an endoscopic surgery system. Fig. 36 is a block diagram showing an example of the functional configuration of a camera head and a CCU.

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

[0009] 1. Embodiments Fig. 1 is a block diagram showing an example of a schematic configuration of an imaging device which is an example of a photodetection device according to an embodiment of the present disclosure. Fig. 2 is a diagram showing an example of a pixel unit of the imaging device according to the embodiment. The photodetection device is a device capable of detecting incident light. The imaging device 1 which is an example of a photodetection device has a plurality of pixels P each having a photoelectric conversion unit (photoelectric conversion region), 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 photoelectric conversion unit of each pixel P is provided. The photoelectric conversion unit of each pixel P is, for example, a photodiode (PD) that is configured to be able to photoelectrically convert light. The photoelectric conversion unit of each pixel P can also be referred to as a photoelectric conversion element.

[0011] 1 or 2, the imaging device 1 has a region (pixel section 100) in which a plurality of pixels P are provided. The pixel section 100 is a pixel array in which a plurality of pixels P are arranged, and can also be called a light receiving region. The imaging device 1 has, for example, the pixel section 100 in which a plurality of pixels P are two-dimensionally arranged in a matrix as an imaging area.

[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 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] 2, the incident direction of light from the subject to be measured is the Z-axis direction, the left-right direction on the paper surface perpendicular to the Z-axis direction is the X-axis direction, and the up-down direction on the paper surface perpendicular to the Z-axis and X-axis directions is the Y-axis direction. In the following figures, directions may be indicated based on the direction of the arrow in FIG. 2.

[0015] 1, the imaging device 1 includes, for example, a pixel unit 100 (pixel array), 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.

[0016] The control lines L1 are signal lines capable of transmitting signals for controlling the pixels P, and are connected to the pixel control unit 111 and the pixels P of the pixel unit 100. In the example shown in FIG. 1 , the pixel unit 100 is provided with a plurality of control lines L1 for each pixel row made up of a plurality of pixels P aligned in the horizontal direction (row direction). The control lines L1 are configured to transmit control signals for reading out signals from the pixels P.

[0017] The plurality of control lines L1 for each pixel row of the imaging device 1 include, for example, wiring for transmitting signals for controlling transfer transistors, wiring for transmitting signals for controlling selection transistors, wiring for transmitting signals for controlling reset transistors, etc. The control lines L1 can also be referred to as drive lines (or pixel drive lines) for transmitting signals for driving the pixels P.

[0018] The signal line L2 is a signal line capable of transmitting a signal from the pixel P, and is connected to the pixel P of the pixel unit 100 and the signal processing unit 112. In the pixel unit 100, for example, one or more signal lines L2 are wired for each pixel column formed by a plurality of pixels P aligned in the vertical direction (column direction).

[0019] The signal line L2 is electrically connected to the pixel P and configured to be able to transmit a signal output from the pixel P. In the imaging device 1, multiple signal lines L2 may be provided for one pixel column. For example, the imaging device 1 may have multiple signal lines L2 for each pixel column including multiple pixels P.

[0020] The pixel control unit 111 is configured to be able to control each pixel P of the pixel unit 100. The pixel control unit 111 is a control circuit and is configured by a plurality of circuits including, for example, a buffer, a shift register, an address decoder, etc. The pixel control unit 111 generates a signal for controlling the pixel P and outputs it to each pixel P of the pixel unit 100 via a control line L1. The pixel control unit 111 is controlled by the control unit 113 and controls the pixels P of the pixel unit 100.

[0021] The pixel control unit 111 generates signals for controlling the pixels P, 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 P, and supplies these signals to each pixel P via a control line L1. The pixel control unit 111 can control reading of pixel signals from each pixel P. The pixel control unit 111 can also be said to be a pixel driving unit configured to be able to drive each pixel P.

[0022] The signal processing unit 112 is configured to be able to perform signal processing of input pixel signals. The signal processing unit 112 is a signal processing circuit and includes, for example, a load circuit, an AD (Analog-Digital) conversion circuit, a horizontal selection switch, etc. The load circuit is, for example, configured by a current source capable of supplying current to the amplification transistor of the pixel P. The load circuit, together with the amplification transistor of the pixel P, forms, for example, a source follower circuit.

[0023] The signal processing unit 112 may have an amplifier circuit configured to be able to amplify signals read out from the pixels P 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, for example. A load circuit, an amplifier circuit, an AD conversion circuit, etc. may be provided for each pixel column of the pixel unit 100.

[0024] The signals output from each pixel P selected and scanned by the pixel control unit 111 are input to the signal processing unit 112 via a signal line L2. The signal processing unit 112 can perform signal processing such as AD conversion of the signal from the pixel P and CDS (Correlated Double Sampling). The signals from each pixel P transmitted via each signal line L2 are subjected to signal processing by the signal processing unit 112 and output to the processing unit 114.

[0025] 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.

[0026] 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.

[0027] 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.

[0028] The pixel unit 100, pixel control unit 111, signal processing unit 112, control unit 113, processing unit 114, etc. may be provided on a single substrate or may be provided separately on multiple substrates. The imaging device 1 may have a stacked structure formed by stacking multiple substrates, for example.

[0029] The pixel control unit 111, the signal processing unit 112, the control unit 113, the processing unit 114, etc. of the imaging device 1 may be provided as, for example, peripheral circuits in a peripheral region of the pixel unit 100. Note that some or all of the signal processing unit 112, the control unit 113, and the processing unit 114 may be configured integrally.

[0030] 3A and 3B are diagrams illustrating an example of a planar configuration of an imaging device according to an embodiment. Fig. 3B illustrates an example of a planar configuration of a semiconductor layer 10 in which a photoelectric conversion unit 12 is provided, and Fig. 3A illustrates an example of a planar configuration of an optical layer 70 provided above the semiconductor layer 10.

[0031] As shown in the example of Fig. 3A , the pixel P of the imaging device 1 has a region (element region 60) in which the structure 51 is provided. For example, a minute structure 51 is disposed in the element region 60 of each pixel P of the pixel unit 100. The element region 60 has the structure 51 and a member 55 disposed around the structure 51. In the example shown in Fig. 3A , a plurality of structures 51 are disposed in the element region 60.

[0032] The element region 60 corresponds to one region when the optical layer 70 is divided into regions for each pixel P. Note that the structures 51 may also be provided at the boundary between adjacent element regions 60. In the example shown in FIG. 3A , some of the structures 51 are arranged across two adjacent element regions 60. The structures 51 may also be provided at an intersection that forms the boundary between four pixels P (or element regions 60), a side that forms the boundary between two pixels P adjacent in the X-axis direction (or Y-axis direction), etc.

[0033] The imaging device 1 has structures 51 as nanostructures, and is configured to guide incident light toward the photoelectric conversion unit 12. The structures 51 are, for example, structures having a columnar (pillar-like) shape. As an example, the structures 51 are pillars (columnar members) having a cylindrical shape. The shape of each structure 51 in the element region 60 can be changed as appropriate. For example, the structures 51 may have a polygonal shape in a planar view.

[0034] The member 55 is, for example, a member arranged so as to fill the spaces between adjacent structures 51, and can also be called a filling member. The structure 51 can also be said to be provided within the member 55 and arranged so as to replace part of the member 55. The structure 51 is made of, for example, a dielectric material having a refractive index different from that of the member 55. Note that the number and arrangement of the structures 51 are not limited to the example shown in the figure and can be changed as appropriate.

[0035] A plurality of pixels P are provided in the pixel section 100 of the imaging device 1, arranged, for example, in the horizontal direction (X-axis direction) and vertical direction (Y-axis direction). The plurality of pixels P of the pixel section 100 include, for example, a pixel Pr (R pixel) that receives and photoelectrically converts light in the red (R) wavelength range, pixels Pg1 and Pg2 (G pixels) that receive and photoelectrically convert light in the green (G) wavelength range, and a pixel Pb (B pixel) that receives and photoelectrically converts light in the blue (B) wavelength range.

[0036] In the pixel unit 100, a plurality of R pixels, a plurality of G pixels, and a plurality of B pixels are arranged in a repeated manner. As an example, the R pixels, G pixels, and B pixels are arranged according to a Bayer array. In the pixel unit 100, 2×2 pixels each consisting of a pixel Pr, a pixel Pg1, a pixel Pg2, and a pixel Pb are arranged in a repeated manner. The pixel unit 100 has, for example, a pixel row in which the pixel Pr and the pixel Pg1 are arranged alternately, and a pixel row in which the pixel Pg2 and the pixel Pb are arranged alternately.

[0037] The R pixels, G pixels, and B pixels of the pixel unit 100 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 P in the pixel unit 100 can be set arbitrarily.

[0038] A pixel P of the imaging device 1 has a plurality of cells C (cells C1, C2, C3, and C4 in the example shown in FIG. 3B ). In each pixel P of the imaging device 1, for example, a plurality of cells C each including a photoelectric conversion unit 12 are arranged adjacent to one another. As an example, the plurality of cells C are arranged aligned in the X-axis direction and the Y-axis direction as shown in FIG. 3B .

[0039] In the example shown in Figure 3B, pixel Pr, pixels Pg1, Pg2, and pixel Pb each have cells C1 to C4. In pixel P, cell C2 is located next to cell C1. Cell C4 is located next to cell C3. Note that the number and arrangement of cells C in each pixel P are not limited to the example shown and can be changed as appropriate.

[0040] 4 is a diagram showing an example of the circuit configuration of a pixel of the imaging device 1 according to the embodiment. Each pixel P of the imaging device 1 includes a plurality of photoelectric conversion units 12 (in FIG. 4, the photoelectric conversion units 12 of cells C1 to C4), a plurality of transistors TR (in FIG. 4, the transistors TR1 of cells C1 to TR4 of cells C4), a floating diffusion FD, and a readout circuit 20.

[0041] The photoelectric conversion unit 12 (i.e., photoelectric conversion region) is configured to receive light and generate a signal. The photoelectric conversion unit 12 is configured to be able to generate electric charges through photoelectric conversion. The photoelectric conversion unit 12 can also be called a light receiving unit (light receiving element). In the example shown in FIG. 4, the photoelectric conversion unit 12 of each of cells C1 to C4 is a photodiode (PD). Each photoelectric conversion unit 12 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.

[0042] The transistors TR (transistors TR1, TR2, TR3, and TR4 in FIG. 4) are transfer transistors, and are configured to be able to transfer charges photoelectrically converted by the photoelectric conversion unit 12 to the floating diffusion FD. The transistors TR electrically connect or disconnect the photoelectric conversion unit 12 and the floating diffusion FD. In the example shown in FIG. 4, the transistors TR1 to TR4 are controlled by different signals.

[0043] The transistor TR1 is controlled by a signal STR1 to electrically connect or disconnect the photoelectric conversion unit 12 of the cell C1 to the floating diffusion FD. The transistor TR1 can transfer the charge that is photoelectrically converted and accumulated in the photoelectric conversion unit 12 of the cell C1 to the floating diffusion FD.

[0044] The transistor TR2 is controlled by a signal STR2 to electrically connect or disconnect the photoelectric conversion unit 12 of the cell C2 to the floating diffusion FD. The transistor TR2 can transfer the charge that is photoelectrically converted and stored in the photoelectric conversion unit 12 of the cell C2 to the floating diffusion FD.

[0045] The transistor TR3 is controlled by a signal STR3 to electrically connect or disconnect the photoelectric conversion unit 12 of the cell C3 to the floating diffusion FD. The transistor TR3 can transfer the charge that is photoelectrically converted and accumulated in the photoelectric conversion unit 12 of the cell C3 to the floating diffusion FD.

[0046] Furthermore, the transistor TR4 is controlled by a signal STR4 to electrically connect or disconnect the photoelectric conversion unit 12 of the cell C4 to the floating diffusion FD. The transistor TR4 can transfer the charge that is photoelectrically converted and accumulated in the photoelectric conversion unit 12 of the cell C4 to the floating diffusion FD.

[0047] 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.

[0048] The readout circuit 20 is configured to be able to output signals based on the photoelectrically converted charges, including a first pixel signal based on the charges generated by the photoelectric conversion unit 12 of cell C1, a second pixel signal based on the charges generated by the photoelectric conversion unit 12 of cell C2, a third pixel signal based on the charges generated by the photoelectric conversion unit 12 of cell C3, and a fourth pixel signal based on the charges generated by the photoelectric conversion unit 12 of cell C4.

[0049] The readout circuit 20 includes, for example, a transistor AMP, a transistor SEL, and a transistor RST. 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.

[0050] 4, 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, for example, a power supply line to which a power supply voltage (power supply voltage VDD in the example shown in FIG. 4) is supplied.

[0051] 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.

[0052] 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. 4. 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.

[0053] 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 pixel signals (first to fourth pixel signals) of the pixel P to the 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. 4) is applied. The transistor SEL may also be omitted as necessary.

[0054] The transistor RST is configured to be able to reset the voltage of the floating diffusion FD. In the example shown in Fig. 4, 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 P. The transistor RST is a reset transistor.

[0055] The transistor RST is controlled by a signal SRST and can reset the charge accumulated in the floating diffusion FD and reset the potential 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 TR.

[0056] 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.

[0057] When the switching transistor is turned on, the capacitance added to the floating diffusion FD of the pixel P increases, and the conversion efficiency (i.e., conversion 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.

[0058] The above-mentioned transistor TR (transfer transistor), transistor AMP (amplification transistor), transistor SEL (selection transistor), transistor RST (reset transistor), and switching transistor are each, for example, a MOS transistor (MOSFET) having gate, source, and drain terminals.

[0059] 4, the transistors TR1 to TR4, the transistor AMP, the transistor SEL, and the transistor RST are each configured as an NMOS transistor. Note that the transistor of the pixel P may also be configured as a PMOS transistor.

[0060] The pixel control unit 111 (see FIG. 1) of the imaging device 1 supplies control signals to the gates of the transistors TR1 to TR4, the transistor SEL, the transistor RST, the switching transistor, etc. of each pixel P via the control line L1 described above, thereby turning the transistors on (conducting state) or off (non-conducting state).

[0061] The multiple control lines L1 for each pixel row of the imaging device 1 include, for example, a wiring for transmitting a signal STR1 that controls transistor TR1, a wiring for transmitting a signal STR2 that controls transistor TR2, a wiring for transmitting a signal STR3 that controls transistor TR3, and a wiring for transmitting a signal STR4 that controls transistor TR4.

[0062] The control lines L1 include a line for transmitting a signal SSEL for controlling the transistor SEL, a line for transmitting a signal SRST for controlling the transistor RST, a line for transmitting a signal for controlling the switching transistor, and the like.

[0063] The transistors TR1 to TR4, the transistor SEL, the transistor RST, the switching transistors, etc. 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 P to output a pixel signal from each pixel P to a signal line L2. The pixel control unit 111 can control the reading out of the pixel signal of each pixel P to the signal line L2.

[0064] The imaging device 1 may have a configuration in which a plurality of pixels P share one readout circuit 20. For example, in the imaging device 1, the readout circuit 20 may be provided for a plurality of pixels P. A readout circuit 20 is arranged for each of a plurality of pixels P, and the plurality of pixels P share one readout circuit 20. As an example, a 2×2 pixel array consisting of four adjacent pixels P may share one readout circuit 20.

[0065] 5 is a diagram showing an example of a cross-sectional configuration of an imaging device according to an embodiment. The imaging device 1 has an optical layer 70, a spacer layer 90, a semiconductor layer 10, and a wiring layer 95. The imaging device 1 has a configuration in which the optical layer 70, the spacer layer 90, the semiconductor layer 10, and the wiring layer 95 are stacked in the Z-axis direction. The optical layer 70, the spacer layer 90, the semiconductor layer 10, and the wiring layer 95 are provided from the light incident side.

[0066] 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 so as to be aligned in the X-axis direction (or the Y-axis direction). 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 referred to as a metasurface element. The optical layer 70 can also be referred to as a metasurface layer or a metamaterial layer.

[0067] 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 also be called nanopillars. The structures 51 and the members 55 are made of materials having refractive indices different from each other. The optical layer 70 including the structures 51 is provided by being stacked on the spacer layer 90.

[0068] The semiconductor layer 10 is composed of a semiconductor substrate (e.g., 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.

[0069] 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. For example, the surface 11S1 of the semiconductor layer 10 is a light-receiving surface (light incident surface). The surface 11S2 of the semiconductor layer 10 is an element formation surface on which elements such as transistors are formed. A gate electrode, a gate insulating film (e.g., a gate oxide film), etc. may be provided on the surface 11S2 of the semiconductor layer 10.

[0070] 5 , a spacer layer 90 is provided on the surface 11S1 side of the semiconductor layer 10. The optical layer 70 and the spacer layer 90 are stacked on the semiconductor layer 10 in a thickness direction perpendicular to the surface 11S1 of the semiconductor layer 10. A wiring layer 95 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 95 is provided on the side opposite to the side where the light is incident.

[0071] In the semiconductor layer 10, a plurality of photoelectric conversion units 12 (photoelectric conversion regions) 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 are photoelectric conversion regions and can also be referred to as photoelectric conversion layers. The photoelectric conversion units 12 perform photoelectric conversion on light incident via the optical layer 70 and the spacer layer 90.

[0072] The wiring layer 95 is provided by being laminated on the semiconductor layer 10. The wiring layer 95 includes, for example, a conductor film and an insulating film, and has a plurality of wirings and vias. The wiring layer 95 has a configuration in which a plurality of wirings are laminated via an insulating film serving as an interlayer insulating film (interlayer insulating layer). The wiring layer 95 is a multi-layer wiring layer, and includes, for example, two or more layers of wirings, or three or more layers of wirings.

[0073] The wiring of the wiring layer 95 is formed using a metal material such as aluminum (Al), tungsten (W), or copper (Cu). The wiring of the wiring layer 95 may be formed using polysilicon (Poly-Si) or other conductive materials. The interlayer insulating film is formed using, for example, silicon oxide (SiO), silicon nitride (SiN), silicon oxynitride (SiON), or the like.

[0074] The semiconductor layer 10 and the wiring layer 95 are provided with, for example, the above-described readout circuit 20 (see FIG. 4 ) for each pixel P or for each set of pixels P. The above-described pixel control unit 111, signal processing unit 112, control unit 113, processing unit 114 (see FIG. 1 ), etc. may be provided on the semiconductor layer 10 and the wiring layer 95, or on a substrate separate from the semiconductor layer 10.

[0075] The spacer layer 90 is provided between the semiconductor layer 10 and the optical layer 70. The spacer layer 90 is made of an insulating film such as an oxide film, a nitride film, or an oxynitride film, and can also be called an insulating layer. The spacer layer 90 may be made of an insulating material such as silicon oxide, silicon nitride, or aluminum oxide (AlO), or may be made of other materials.

[0076] The spacer layer 90 (insulating layer) may be made of a material with a low refractive index, such as silicon oxide. The spacer layer 90 may also be made of another material that transmits light in the wavelength range to be measured. The spacer layer 90 can also be called a transparent layer that transmits light.

[0077] As shown in Fig. 5 and Fig. 3B , the imaging device 1 is provided with an inter-pixel isolation portion 30. The inter-pixel isolation portion 30 is an isolation region (isolation portion) provided around the cell C (or the photoelectric conversion portion 12). The inter-pixel isolation portion 30 (isolation region) is provided between a plurality of adjacent photoelectric conversion portions 12 in the semiconductor layer 10. The inter-pixel isolation portion 30 is configured using, for example, a trench (groove portion).

[0078] As shown in FIG. 3B , for example, the inter-pixel isolation portion 30 is provided so as to surround the photoelectric conversion portion 12 on all four sides in a plan view. The inter-pixel isolation portion 30 may be formed in a lattice shape in the semiconductor layer 10 so as to surround the photoelectric conversion portion 12 of each cell C. A portion of the inter-pixel isolation portion 30 is provided at the boundary between adjacent pixels P. The inter-pixel isolation portion 30 can also be referred to as an inter-pixel isolation wall.

[0079] 5 , the inter-pixel isolation portion 30 may be provided so as to penetrate the semiconductor layer 10. The inter-pixel isolation portion 30 has, for example, a full trench isolation (FTI) structure and is formed so as to reach the surface 11S2 of the semiconductor layer 10. The inter-pixel isolation portion 30 may be provided from the surface 11S1 of the semiconductor layer 10 to between the surfaces 11S1 and 11S2 of the semiconductor layer 10.

[0080] 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 inter-pixel isolation portion 30. Polysilicon, a metal material, another insulating material, or the like may be filled in the trench of the inter-pixel isolation portion 30. The inter-pixel isolation portion 30 may be formed using another insulating material having a low refractive index. A void (cavity) may be provided in the inter-pixel isolation portion 30. The inter-pixel isolation portion 30 may be configured of a semiconductor region (a p-type semiconductor region or an n-type semiconductor region) formed by ion implantation.

[0081] A light-shielding member (light-shielding portion) may be provided as the inter-pixel isolation portion 30. For example, a light-absorbing material may be provided inside the trench of the inter-pixel isolation portion 30. As one example, tungsten (W) may be embedded in the trench of the inter-pixel isolation portion 30. For example, the inter-pixel isolation portion 30 may be made of polysilicon. The inter-pixel isolation portion 30 may also be formed using other materials that block light. The inter-pixel isolation portion 30 is made of a light-shielding member and may also be called a light-shielding wall or an inter-cell light-shielding wall.

[0082] In the imaging device 1, the provision of the inter-pixel separator 30 can prevent light from leaking into the surrounding cells C. This can prevent unnecessary light from leaking into the surrounding photoelectric conversion units 12, thereby preventing color mixing, for example. It can also prevent noise from being mixed into pixel signals.

[0083] The imaging device 1 may have at least one of a fixed charge film and an anti-reflection film on the surface 11S1 side of the semiconductor layer 10. The fixed charge film and the anti-reflection film may be made of, for example, a metal compound (metal oxide, metal nitride, etc.) and may also be referred to as a metal compound layer. The fixed charge film is a film having a fixed charge and may be formed using a high-dielectric material.

[0084] The fixed charge film is, for example, 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. A portion of each of the fixed charge film and the antireflection film may be provided in the semiconductor layer 10 so as to extend along the sidewall (side surface) of the inter-pixel isolation portion 30.

[0085] 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.

[0086] 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, silicon oxide, or aluminum oxide, or may be made of other materials.

[0087] As shown in the example of FIG. 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 optical layer 70. For example, light transmitted through an optical system such as an imaging lens is incident on the structures 51 of the optical layer 70. For example, the structures 51 have a size equal to or smaller than a predetermined wavelength of the incident light when viewed in a plan view (i.e., when viewed on the XY plane). Note that the size of the structures 51 when viewed on the XZ plane or the YZ plane (for example, the height of the cylindrical structures 51) may be equal to or smaller than the predetermined wavelength of the incident light, or may be larger than the wavelength of the incident light.

[0088] The optical layer 70 has nanostructures 51, and is configured to guide light incident from above in Fig. 5 toward the photoelectric conversion unit 12. When viewed in the XY plane, 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.

[0089] The multiple structures 51 in each element region 60 are arranged side by side in the X-axis direction or the Y-axis direction, with part of the member 55 sandwiched between them. As an example, the structures 51 have a cylindrical shape. Note that the shape of the structures 51 can be changed as appropriate, and may be a circle or a square in a plan view. The shape of the structures 51 may be an ellipse, a polygon, a cross, or any other shape.

[0090] 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.

[0091] The optical layer 70 utilizes the structures 51, which are nanostructures, to propagate light toward the photoelectric conversion unit 12. The structures 51 are also called, for example, nanopillars, metaatoms, nanoatoms, nanoposts, metasurface structures, microstructures, etc. The optical layer 70 is an optical element (optical member) that guides (propagates) light.

[0092] The optical layer 70 is configured to, for example, impart a phase delay to incident light and guide the light. As an example, the optical layer 70 is provided with a plurality of structures 51 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 a predetermined photoelectric conversion unit 12.

[0093] 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 at intervals equal to or less than the wavelength range of visible light in the X-axis direction and the Y-axis direction. Note that the plurality of structures 51 may also be arranged at intervals equal to or less than the wavelength range of infrared light in the XY plane.

[0094] 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.

[0095] 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.

[0096] 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.

[0097] 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.

[0098] 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.

[0099] 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.

[0100] 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.

[0101] 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).

[0102] The optical layer 70 can control the wavefront of the light by, for example, causing a phase delay in the incident light due to the difference in refractive index between the structure 51 and the surrounding medium. The optical layer 70 can adjust the propagation direction of the light by, for example, imparting a phase delay to the incident light using the structure 51 and the member 55 surrounding the structure 51. The light to which the phase is imparted by the optical layer 70 propagates through the spacer layer 90 and reaches the photoelectric conversion unit 12 of the cell C.

[0103] In each pixel P of the imaging device 1, for example, the effective refractive index of 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.

[0104] 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.

[0105] The optical layer 70 may be configured as a spectroscopic unit (spectroscopic element) capable of separating incident light. The optical layer 70 may be configured as a splitter (color splitter) and may also be referred to as a color splitter layer or a color separation layer. The optical layer 70 may also be referred to as an optical element configured to redirect light. The optical layer 70 allows light of a desired wavelength range to be efficiently guided to the photoelectric conversion unit 12.

[0106] The optical layer 70 can adjust the propagation direction of light by, for example, imparting different amounts of phase delay depending on the wavelength of the light, and can separate the incident light into light of each wavelength range. The propagation direction of light of each wavelength by the optical layer 70 can be adjusted by the material (refractive index), width, height, arrangement position (pitch), etc. of the structures 51.

[0107] In the imaging device 1, the material, size, arrangement number, etc. of the structures 51 are determined so that light in a specific wavelength band to be detected branches off and travels to the photoelectric conversion unit 12 of the desired cell C. For example, the size, arrangement interval, etc. of the structures 51 in the pixel P of each color are set to obtain a desired light collection range for each pixel P of each color. For example, the structures 51 in each element region 60 of pixel Pr, pixels Pg1, Pg2, and pixel Pb may be formed so that their sizes (e.g., width, height), arrangement positions, etc. are different from one another.

[0108] As described above, light from a subject to be measured is incident on the photoelectric conversion unit 12 of each cell C of the imaging device 1 via the optical layer 70. Each cell C can generate a pixel signal by photoelectrically converting the light incident via the optical layer 70. The imaging device 1 can generate image data representing an image of the subject using the pixel signal obtained by photoelectric conversion in each cell C.

[0109] 6 and 7 are diagrams showing examples of cross-sectional configurations of an imaging device according to an embodiment, in which Fig. 6 shows an example of the cross-sectional configuration of a pixel row including pixel Pr and pixel Pg1, and Fig. 7 shows an example of the cross-sectional configuration of a pixel row including pixel Pg2 and pixel Pb.

[0110] 6 and 7, the dashed arrow Lr schematically represents red light. The solid arrows Lg1 and Lg2 schematically represent green light. The dashed arrow Lb in Fig. 7 schematically represents blue light. Furthermore, the hollow arrows in Fig. 6 and 7 schematically represent light incident on the optical layer 70 including the structures 51.

[0111] The optical layer 70 of the imaging device 1 has a region (referred to as the first light collection region 71) that collects light in a first wavelength band (e.g., light in the red wavelength band) of the incident light, and a region (referred to as the second light collection region 72) that collects light in a second wavelength band (e.g., light in the green wavelength band).

[0112] Furthermore, the optical layer 70 has a region (referred to as a third light collection region 73) that collects light of a third wavelength band (e.g., light of a blue wavelength band) of the incident light. In the optical layer 70, the first to third light collection regions 71 to 73 adjust the traveling directions of the red light, green light, and blue light as the first to third wavelength light.

[0113] The first light collecting region 71 is provided for, for example, the pixel Pr, which is an R pixel. The first light collecting region 71 is positioned so as to overlap the photoelectric conversion unit 12 of each cell C of the pixel Pr when viewed from above the optical layer 70. The first light collecting region 71 has a number of divided regions 81 (e.g., divided region 81a, divided region 81b, divided region 81c, and divided region 81d) corresponding to the number of cells C of the pixel Pr (see also FIG. 8A described later).

[0114] The divided regions 81a to 81d are, for example, regions obtained by dividing the first light collection region 71 into approximately equal parts and are positioned adjacent to each other. In the example shown in Figure 6, the divided region 81a is positioned adjacent to the divided region 81b. The divided region 81c is positioned adjacent to the divided region 81d.

[0115] Each of the divided regions 81a to 81d can have a light receiving area that is approximately the same as the area of ​​one pixel P. For example, in a plan view (i.e., when viewed on the XY plane), the light receiving area of ​​the divided region 81a, the light receiving area of ​​the divided region 81b, the light receiving area of ​​the divided region 81c, and the light receiving area of ​​the divided region 81d are each approximately the same as the area of ​​the pixel Pr (see also FIG. 8A).

[0116] The divided region 81a of the first light collection region 71 is provided to correspond to the cell C1 of the pixel Pr, the divided region 81b is provided to correspond to the cell C2 of the pixel Pr, the divided region 81c is provided to correspond to the cell C3 of the pixel Pr, and the divided region 81d is provided to correspond to the cell C4 of the pixel Pr.

[0117] The second light collecting region 72 is provided for, for example, pixel Pg1, which is a G pixel. When viewed from above the optical layer 70, the second light collecting region 72 is positioned so as to overlap with the photoelectric conversion unit 12 of each cell C of pixel Pg1. The second light collecting region 72 has a number of divided regions 82 (e.g., divided region 82a, divided region 82b, divided region 82c, and divided region 82d) corresponding to the number of cells C of pixel Pg1 (see also Figures 9A and 10A described below).

[0118] The divided regions 82a to 82d are, for example, regions obtained by dividing the second light collection region 72 into approximately equal parts and are located adjacent to each other. In the example shown in Figure 6, the divided region 82a is located adjacent to the divided region 82b. The divided region 82c is located adjacent to the divided region 82d.

[0119] Each of the divided regions 82a to 82d can have a light receiving area that is approximately the same as the area of ​​one pixel P. For example, in a plan view, the light receiving area of ​​the divided region 82a, the light receiving area of ​​the divided region 82b, the light receiving area of ​​the divided region 82c, and the light receiving area of ​​the divided region 82d are each approximately the same as the area of ​​the pixel Pg1 (or pixel Pg2) (see also FIGS. 9A and 10A, which will be described later).

[0120] The divided region 82a of the second light collection region 72 is provided to correspond to the cell C1 of the pixel Pg1, the divided region 82b is provided to correspond to the cell C2 of the pixel Pg1, the divided region 82c is provided to correspond to the cell C3 of the pixel Pg1, and the divided region 82d is provided to correspond to the cell C4 of the pixel Pg1.

[0121] The second light collecting region 72 in the optical layer 70 can be configured as a region that overlaps with a portion of the first light collecting region 71. For example, the divided region 81b of the first light collecting region 71 overlaps with at least a portion of the divided region 82a of the second light collecting region 72 and includes at least a portion of the divided region 82a. It can also be said that the divided region 81b and the divided region 82a are provided so as to overlap each other.

[0122] 6 , for example, the divided regions 82 a of the second light collecting region 72 and the divided regions 81 b of the first light collecting region 71 overlap each other. In the example shown in FIG. 6 , the divided regions 82 a of the second light collecting region 72 in the optical layer 70 also correspond to the divided regions 81 b of the first light collecting region 71.

[0123] 7, the second light collecting region 72 is also provided for the pixel Pg2, which is a G pixel. When viewed from above the optical layer 70, the second light collecting region 72 is positioned so as to overlap with the photoelectric conversion unit 12 of each cell C of the pixel Pg2. The optical layer 70 has a second light collecting region 72 corresponding to the pixel Pg1 and a second light collecting region 72 corresponding to the pixel Pg2.

[0124] 7, the divided region 82a is provided corresponding to the cell C1 of the pixel Pg2, the divided region 82b is provided corresponding to the cell C2 of the pixel Pg2, the divided region 82c is provided corresponding to the cell C3 of the pixel Pg2, and the divided region 82d is provided corresponding to the cell C4 of the pixel Pg2.

[0125] The third light collecting region 73 is provided for, for example, pixel Pb, which is a B pixel. The third light collecting region 73 is positioned so as to overlap with the photoelectric conversion unit 12 of each cell C of the pixel Pb when viewed from above the optical layer 70. The third light collecting region 73 has a number of divided regions 83 (e.g., divided region 83a, divided region 83b, divided region 83c, and divided region 83d) corresponding to the number of cells C of the pixel Pb (see also FIG. 11A described later).

[0126] The divided regions 83a to 83d are, for example, regions obtained by dividing the third light collection region 73 into approximately equal parts and are located adjacent to each other. In the example shown in Figure 7, the divided region 83a is located adjacent to the divided region 83b. The divided region 83c is located adjacent to the divided region 83d.

[0127] Each of the divided regions 83a to 83d can have a light receiving area that is approximately the same as the area of ​​one pixel P. For example, in a plan view, the light receiving area of ​​the divided region 83a, the light receiving area of ​​the divided region 83b, the light receiving area of ​​the divided region 83c, and the light receiving area of ​​the divided region 83d are each approximately the same as the area of ​​the pixel Pb (see also FIG. 11A, which will be described later).

[0128] The divided region 83a of the third light collection region 73 is provided to correspond to the cell C1 of the pixel Pb, the divided region 83b is provided to correspond to the cell C2 of the pixel Pb, the divided region 83c is provided to correspond to the cell C3 of the pixel Pb, and the divided region 83d is provided to correspond to the cell C4 of the pixel Pb.

[0129] The first light collecting region 71 corresponding to the pixel Pr is configured to be able to propagate red (R) light of the incident light to the photoelectric conversion unit 12 of that pixel Pr. The first light collecting region 71 is also configured to propagate green (G) light of the incident light to the photoelectric conversion unit 12 of the pixel Pg1 or Pg2, and blue (B) light to the photoelectric conversion unit 12 of the pixel Pb. The first light collecting region 71 splits the incident light, and guides light in the green wavelength range of the incident light toward the pixel Pg1 or Pg2, and light in the blue wavelength range toward the pixel Pb.

[0130] The divided region 81a of the first light collection region 71 is configured to collect light in the red wavelength range of the incident light onto the photoelectric conversion unit 12 of the cell C1 of the pixel Pr. The divided region 81b of the first light collection region 71 is configured to collect light in the red wavelength range of the incident light onto the photoelectric conversion unit 12 of the cell C2 of the pixel Pr.

[0131] The divided region 81c of the first light collection region 71 is configured to collect light in the red wavelength range of the incident light onto the photoelectric conversion unit 12 of the cell C3 of the pixel Pr. The divided region 81d of the first light collection region 71 is configured to collect incident light in the red wavelength range onto the photoelectric conversion unit 12 of the cell C4 of the pixel Pr.

[0132] 6 , the optical layer 70 focuses light in the red wavelength range that is incident on the divided region 81a onto the photoelectric conversion unit 12 of the cell C1 of the pixel Pr, and focuses light in the red wavelength range that is incident on the divided region 81b onto the photoelectric conversion unit 12 of the cell C2 of the pixel Pr. In addition, the optical layer 70 focuses light in the red wavelength range that is incident on the divided region 81c onto the photoelectric conversion unit 12 of the cell C3 of the pixel Pr, and focuses light in the red wavelength range that is incident on the divided region 81d onto the photoelectric conversion unit 12 of the cell C4 of the pixel Pr.

[0133] The second light collecting region 72 corresponding to pixel Pg1 is configured to be able to propagate green (G) light of the incident light to the photoelectric conversion unit 12 of that pixel Pg1. The second light collecting region 72 is also configured to propagate red (R) light of the incident light to the photoelectric conversion unit 12 of pixel Pr and blue (B) light to the photoelectric conversion unit 12 of pixel Pb. The second light collecting region 72 splits the incident light, and guides light in the red wavelength range of the incident light toward pixel Pr and light in the blue wavelength range of the incident light toward pixel Pb.

[0134] The divided region 82a of the second light collection region 72 provided for the pixel Pg1 is configured to collect light in the green wavelength range of the incident light onto the photoelectric conversion unit 12 of the cell C1 of the pixel Pg1. The divided region 82b of the second light collection region 72 is configured to collect light in the green wavelength range of the incident light onto the photoelectric conversion unit 12 of the cell C2 of the pixel Pg1.

[0135] Furthermore, divided region 82c of second light collection region 72 is configured to collect light in the green wavelength range of the incident light onto photoelectric conversion unit 12 of cell C3 of pixel Pg1. Divided region 82d of second light collection region 72 is configured to collect incident light in the green wavelength range onto photoelectric conversion unit 12 of cell C4 of pixel Pg1.

[0136] 6, the optical layer 70 focuses light in the green wavelength range that is incident on the divided region 82a of the pixel Pg1 onto the photoelectric conversion unit 12 of the cell C1 of the pixel Pg1, and focuses light in the green wavelength range that is incident on the divided region 82b onto the photoelectric conversion unit 12 of the cell C2 of the pixel Pg1. In addition, the optical layer 70 focuses light in the green wavelength range that is incident on the divided region 82c onto the photoelectric conversion unit 12 of the cell C3 of the pixel Pg1, and focuses light in the green wavelength range that is incident on the divided region 82d onto the photoelectric conversion unit 12 of the cell C4 of the pixel Pg1.

[0137] In the second light-collecting region 72 corresponding to pixel Pg2, the divided region 82a is configured to collect light in the green wavelength range of incident light onto the photoelectric conversion unit 12 of cell C1 of pixel Pg2. In addition, the divided region 82b of the second light-collecting region 72 is configured to collect light in the green wavelength range of incident light onto the photoelectric conversion unit 12 of cell C2 of pixel Pg2.

[0138] The divided region 82c of the second light collection region 72 corresponding to the pixel Pg2 is configured to collect light in the green wavelength range of the incident light onto the photoelectric conversion unit 12 of the cell C3 of the pixel Pg2. The divided region 82d of the second light collection region 72 is configured to collect incident light in the green wavelength range onto the photoelectric conversion unit 12 of the cell C4 of the pixel Pg2.

[0139] 7, the optical layer 70 focuses light in the green wavelength range that is incident on the divided region 82a of the pixel Pg2 onto the photoelectric conversion unit 12 of the cell C1 of the pixel Pg2, and focuses light in the green wavelength range that is incident on the divided region 82b onto the photoelectric conversion unit 12 of the cell C2 of the pixel Pg2. In addition, the optical layer 70 focuses light in the green wavelength range that is incident on the divided region 82c onto the photoelectric conversion unit 12 of the cell C3 of the pixel Pg2, and focuses light in the green wavelength range that is incident on the divided region 82d onto the photoelectric conversion unit 12 of the cell C4 of the pixel Pg2.

[0140] The third light collecting region 73 corresponding to pixel Pb is configured to be able to propagate blue (B) light, of the incident light, to the photoelectric conversion unit 12 of that pixel Pb. The third light collecting region 73 is also configured to propagate green (G) light, of the incident light, to the photoelectric conversion unit 12 of pixel Pg1 or pixel Pg2, and red (R) light to the photoelectric conversion unit 12 of pixel Pr. The third light collecting region 73 splits the incident light, and guides light in the green wavelength range of the incident light toward pixel Pg1 or pixel Pg2, and light in the red wavelength range of the incident light toward pixel Pr.

[0141] The divided region 83a of the third light collecting region 73 is configured to collect light in the blue wavelength range of the incident light onto the photoelectric conversion unit 12 of the cell C1 of the pixel Pb. The divided region 83b of the third light collecting region 73 is configured to collect light in the blue wavelength range of the incident light onto the photoelectric conversion unit 12 of the cell C2 of the pixel Pb.

[0142] Segment 83c of third light collection region 73 is configured to collect light in the blue wavelength range of incident light onto photoelectric conversion unit 12 of cell C3 of pixel Pb. Segment 83d of third light collection region 73 is configured to collect incident light in the blue wavelength range onto photoelectric conversion unit 12 of cell C4 of pixel Pb.

[0143] 7, the optical layer 70 focuses light in the blue wavelength range that is incident on the divided region 83a onto the photoelectric conversion unit 12 of the cell C1 of the pixel Pb, and focuses light in the blue wavelength range that is incident on the divided region 83b onto the photoelectric conversion unit 12 of the cell C2 of the pixel Pb. In addition, the optical layer 70 focuses light in the blue wavelength range that is incident on the divided region 83c onto the photoelectric conversion unit 12 of the cell C3 of the pixel Pb, and focuses light in the blue wavelength range that is incident on the divided region 83d onto the photoelectric conversion unit 12 of the cell C4 of the pixel Pb.

[0144] 8A and 8B , the divided region 81 a of the first light collection region 71 collects red wavelength light from the incident light onto the cell C1 of the pixel Pr. Red light incident on the divided region 81 a, which includes a part of the element region 60 of the pixel Pr and a part of the element region 60 surrounding the pixel Pr, can be collected onto the photoelectric conversion unit 12 of the cell C1 of the pixel Pr.

[0145] Segment 81b of first light collection region 71 collects incident red wavelength light onto cell C2 of pixel Pr. Segment 81c of first light collection region 71 collects incident red wavelength light onto cell C3 of pixel Pr. Segment 81d of first light collection region 71 collects incident red wavelength light onto cell C4 of pixel Pr. Photoelectric conversion units 12 of cells C1 to C4 of pixel Pr each efficiently receive light in the red wavelength range, perform photoelectric conversion, and generate electric charges according to the amount of light received.

[0146] The optical layer 70 can guide red light incident on the pixel Pr and red light incident on each of the pixels surrounding the pixel Pr to cells C1 to C4 of the pixel Pr by using the first light collection region 71. For example, as shown in the example of FIG. 8B , light can be collected onto the pixel Pr from the first light collection region 71, which has an area four times the area of ​​one pixel, to improve the sensitivity of the pixel Pr. Compared to a case in which an on-chip lens is disposed instead of the optical layer 70 and light is collected onto the pixel Pr from a light collection region having an area one time the area of ​​one pixel by the on-chip lens, the present embodiment can achieve higher sensitivity.

[0147] Furthermore, the optical layer 70 uses divided regions 81a to 81d to focus light on each of the multiple cells C (cells C1 to C4) of the pixel Pr. For example, as shown in the example of FIG. 8B , light can be focused onto one cell C in the pixel Pr from an area that is one time the area of ​​one pixel, thereby improving the sensitivity of the cell C. Compared to a case in which an on-chip lens is disposed instead of the optical layer 70 and light is focused onto one cell C in the pixel Pr from a light-focusing area that is one time the area of ​​one cell C by the on-chip lens, the sensitivity can be increased in this embodiment.

[0148] 9A and 9B , the divided region 82a of the second light collection region 72 corresponding to the pixel Pg1 collects light of a green wavelength among incident light toward the cell C1 of the pixel Pg1. The green light incident on the divided region 82a, which includes a part of the element region 60 of the pixel Pg1 and a part of the element region 60 surrounding the pixel Pg1, can be collected toward the photoelectric conversion unit 12 of the cell C1 of the pixel Pg1.

[0149] Segment 82b of second light collection region 72 corresponding to pixel Pg1 collects incident green wavelength light onto cell C2 of pixel Pg1. Segment 82c of second light collection region 72 collects incident green wavelength light onto cell C3 of pixel Pg1. Segment 82d of second light collection region 72 collects incident green wavelength light onto cell C4 of pixel Pg1. Photoelectric conversion units 12 of cells C1 to C4 of pixel Pg1 each efficiently receive light in the green wavelength range, perform photoelectric conversion, and generate electric charges according to the amount of light received.

[0150] The optical layer 70 can guide the green light incident on the pixel Pg1 and the green light incident on each of the pixels surrounding the pixel Pg1 to the cells C1 to C4 of the pixel Pg1 by the second light collection region 72. For example, as shown in the example in FIG. 9B , the sensitivity of the pixel Pg1 can be improved by collecting light from the second light collection region 72, which has an area twice the area of ​​one pixel, to the pixel Pg1.

[0151] Furthermore, the optical layer 70 uses divided regions 82a to 82d to focus light onto each of the multiple cells C (cells C1 to C4) of pixel Pg1. For example, as shown in the example of FIG. 9B , light can be focused onto one cell C within pixel Pg1 from an area half the area of ​​one pixel, thereby improving the sensitivity of cell C.

[0152] 10A and 10B , the divided region 82a of the second light collection region 72 corresponding to the pixel Pg2 collects light of a green wavelength among the incident light toward the cell C1 of the pixel Pg2. The green light incident on the divided region 82a, which includes a part of the element region 60 of the pixel Pg2 and a part of the element region 60 surrounding the pixel Pg2, can be collected toward the photoelectric conversion unit 12 of the cell C1 of the pixel Pg2.

[0153] Segment 82b of second light collection region 72 corresponding to pixel Pg2 collects incident green wavelength light onto cell C2 of pixel Pg2. Segment 82c of second light collection region 72 collects incident green wavelength light onto cell C3 of pixel Pg2. Segment 82d of second light collection region 72 collects incident green wavelength light onto cell C4 of pixel Pg2. Photoelectric conversion units 12 of cells C1 to C4 of pixel Pg2 each efficiently receive light in the green wavelength range, perform photoelectric conversion, and generate electric charges according to the amount of light received.

[0154] The optical layer 70 can guide the green light incident on the pixel Pg2 and the green light incident on each of the pixels surrounding the pixel Pg2 to the cells C1 to C4 of the pixel Pg2 by the second light collecting region 72. For example, as shown in the example in FIG. 10B , the sensitivity of the pixel Pg2 can be improved by collecting light from the second light collecting region 72, which has an area twice the area of ​​one pixel, to the pixel Pg2.

[0155] Furthermore, the optical layer 70 focuses light onto each of the multiple cells C (cells C1 to C4) of the pixel Pg2 by the divided regions 82a to 82d. For example, as shown in the example of FIG. 10B , light can be focused onto one cell C in the pixel Pg2 from an area half the area of ​​one pixel, thereby improving the sensitivity of the cell C.

[0156] 11A and 11B , the divided region 83a of the third light collection region 73 collects blue wavelength light from the incident light onto the cell C1 of the pixel Pb. The blue light incident on the divided region 83a, which includes a part of the element region 60 of the pixel Pb and a part of the element region 60 around the pixel Pb, can be collected onto the photoelectric conversion unit 12 of the cell C1 of the pixel Pb.

[0157] Segment 83b of third light collecting region 73 collects incident blue wavelength light onto cell C2 of pixel Pb. Segment 83c of third light collecting region 73 collects incident blue wavelength light onto cell C3 of pixel Pb. Segment 83d of third light collecting region 73 collects incident blue wavelength light onto cell C4 of pixel Pb. Photoelectric conversion units 12 of cells C1 to C4 of pixel Pb each efficiently receive light in the blue wavelength range, perform photoelectric conversion, and generate electric charges according to the amount of light received.

[0158] Optical layer 70 can guide blue light incident on pixel Pb and blue light incident on each of the pixels surrounding pixel Pb to cells C1 to C4 of pixel Pb by third light collection region 73. For example, as shown in the example in FIG. 11B , light can be collected from third light collection region 73, which has an area four times the area of ​​one pixel, to pixel Pb, thereby improving the sensitivity of pixel Pb.

[0159] Furthermore, the optical layer 70 focuses light onto each of the multiple cells C (cells C1 to C4) of the pixel Pb using the divided regions 84a to 84d. For example, as shown in the example of FIG. 11B , light can be focused onto one cell C within the pixel Pb from an area that is one time the area of ​​one pixel, thereby improving the sensitivity of the cell C.

[0160] As described above, in the imaging device 1, light that has passed through different divided regions is received by cells C1 to C4 of the pixel P, and photoelectric conversion is performed in each of cells C1 to C4. A pixel signal can be obtained for each cell C, and the resolution can be improved. For example, the resolution of each color can be improved, making it possible to obtain a high-resolution image.

[0161] 12 is a diagram illustrating an example of the configuration of an optical layer of an imaging device according to an embodiment. As shown in the example of FIG. 12, the optical layer 70 can be configured to collect light from a measurement target in a region away from the boundary between adjacent cells C. For example, the divided regions 81a and 81b of the first light collection region 71 each collect light in a region away from the boundary between cells C1 and C2.

[0162] Each divided region of the optical layer 70 is configured to, for example, focus incident light on the center of the cell C. For example, as shown in the example of FIG. 12 , divided region 81a of the first light focusing region 71 focuses light on the center (central region) of cell C1. Furthermore, divided region 81b of the first light focusing region 71 focuses light on the center of cell C2. By configuring the imaging device 1 in this manner, it is possible to improve the resolution.

[0163] The divided region 81a of the first light collecting region 71 is configured to collect light onto the photoelectric conversion unit 12 of cell C1 without collecting light onto the photoelectric conversion unit 12 (photoelectric conversion region) of cell C2. Furthermore, the divided region 81b of the first light collecting region 71 is configured to collect light onto the photoelectric conversion unit 12 of cell C2 without collecting light onto the photoelectric conversion unit 12 of cell C1. Therefore, in this embodiment, the resolution can be improved, and a high-resolution image can be obtained.

[0164] 13A and 13B are diagrams illustrating an example configuration of an imaging device according to an embodiment. In FIG. 13A, arrows represent light rays directed toward cells C1 to C4 of pixel Pr by the optical layer 70. In FIG. 13B, arrows represent light rays directed toward cells C1 to C4 of pixel Pg1 by the optical layer 70. In FIG. 13C, arrows represent light rays directed toward cells C1 to C4 of pixel Pg2 by the optical layer 70. In FIG. 13D, arrows represent light rays directed toward cells C1 to C4 of pixel Pb by the optical layer 70. Furthermore, FIG. 13E illustrates focused spots formed on cells C1 to C4.

[0165] 13A, light is collected individually onto cells C1 to C4 of pixel Pr by divided regions 81a to 81d of first light collection region 71 corresponding to pixel Pr. Also, in imaging device 1, light is collected individually onto cells C1 to C4 of pixel Pg1 by divided regions 82a to 82d of second light collection region 72 corresponding to pixel Pg1, as shown in FIG.

[0166] 13C, light is collected individually onto cells C1 to C4 of pixel Pg2 by divided regions 82a to 82d of second light collection region 72 corresponding to pixel Pg2. Furthermore, as shown in FIG. 13D, light is collected individually onto cells C1 to C4 of pixel Pb by divided regions 83a to 83d of third light collection region 73 corresponding to pixel Pb.

[0167] In this way, in the imaging device 1 according to this embodiment, the spot light in each of the cells C1 to C4 is separated, as shown in the example of Fig. 13E, and the resolution can be improved. In this embodiment, it is possible to prevent a decrease in resolution while improving the sensitivity to incident light.

[0168] [Actions and Effects] The photodetector according to this embodiment includes a semiconductor layer (semiconductor layer 10), a first pixel (e.g., pixel Pr) having a first photoelectric conversion region and a second photoelectric conversion region provided in the semiconductor layer, and an optical layer (optical layer 70) provided above the semiconductor layer and having a plurality of first structures (structures 51). The optical layer includes a first region (e.g., divided region 81a) corresponding to the first photoelectric conversion region and a second region (e.g., divided region 81b) corresponding to the second photoelectric conversion region. The optical layer focuses light in a first wavelength band (e.g., light in the red wavelength band) incident on the first region onto the first photoelectric conversion region (photoelectric conversion unit 12), and focuses light in the first wavelength band incident on the second region onto the second photoelectric conversion region.

[0169] The photodetector (imaging device 1) according to this embodiment includes an optical layer 70 having a plurality of structures 51. The optical layer 70 focuses light in the red wavelength band incident on the divided region 81a of the first light collection region 71 onto the photoelectric conversion unit 12 of cell C1, and focuses light in the red wavelength band incident on the divided region 81b onto the photoelectric conversion unit 12 of cell C2. This makes it possible to improve sensitivity to incident light while suppressing degradation in resolution. This makes it possible to realize a photodetector that can suppress degradation in resolution.

[0170] 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.

[0171] 2. Modifications (2-1. Modification 1) Fig. 14 is a diagram for explaining a configuration example of an imaging device according to Modification 1 of the present disclosure. As shown in Fig. 14, the imaging device 1 according to this modification has a filter 25. The filter 25 is configured to selectively transmit light in a specific wavelength range from among incident light.

[0172] The filter 25 is provided above the photoelectric conversion unit 12, for example, for each pixel P or for each set of pixels P (i.e., for each predetermined number of pixels P). In the example shown in Fig. 14, the filter 25 is provided in the spacer layer 90, between the optical layer 70 and the semiconductor layer 10. The filter 25 is, for example, an RGB color filter.

[0173] In the imaging device 1, for example, the pixel Pr has a filter 25 that transmits red (R) light, the pixels Pg1 and Pg2 have filters 25 that transmit green (G) light, and the pixel Pb has a filter 25 that transmits blue (B) light. The photoelectric conversion unit 12 of the pixel P photoelectrically converts light incident via the optical layer 70 and the filter 25.

[0174] In the imaging device 1 according to this modification, the filter 25 is provided, thereby reducing color mixing between pixels P. This makes it possible to prevent noise from being mixed into pixel signals, and to prevent degradation in the quality of images generated using pixel signals. The filter 25 may be a complementary color filter. The filter 25 may also be a filter that transmits infrared light.

[0175] (2-2. Modification 2) Fig. 15 and Fig. 16 are diagrams for explaining an example configuration of an imaging device according to Modification 2. Fig. 15 shows an example of the planar configuration of the imaging device, and Fig. 16 shows an example of the cross-sectional configuration of the imaging device. The inter-pixel isolation portions 30 may be configured so that the width (thickness) of the inter-pixel isolation portions 30 between pixels P is different from the width of the inter-pixel isolation portions 30 between cells C within a pixel P.

[0176] 15 or 16 , the width W1 (thickness) of the inter-pixel separation portion 30 between multiple pixels P adjacent in the X-axis direction may be larger than the width W2 of the inter-pixel separation portion 30 between multiple cells C adjacent in the X-axis direction. For example, the width W2 of the inter-pixel separation portion 30 between cells C1 and C2 in pixel Pr is smaller than the width W1 of the inter-pixel separation portion 30 between pixel Pr and pixel Pg1.

[0177] Furthermore, the width W3 of the inter-pixel separation portion 30 between the plurality of pixels P adjacent in the Y-axis direction may be larger than the width W4 of the inter-pixel separation portion 30 between the plurality of cells C adjacent in the Y-axis direction. By configuring the imaging device 1 in this manner, it is possible to reduce color mixing between the pixels P while improving the sensitivity of each cell C.

[0178] (2-3. Modification 3) FIGS. 17, 18A, and 18B are diagrams for explaining an example configuration of an imaging device according to Modification 3. FIG. 17 shows an example cross-sectional configuration of the imaging device. FIG. 18A shows an example planar configuration of the imaging device in the direction of line A-A' shown in FIG. 17. Also, FIG. 18B shows an example planar configuration of the imaging device in the direction of line B-B' shown in FIG. Each cell C of a pixel P may have multiple photoelectric conversion units 12. In the example shown in FIG. 17 or FIGS. 18A and 18B, cells C1 to C4 each have a photoelectric conversion unit 12a and a photoelectric conversion unit 12b.

[0179] In the imaging device 1, the photoelectric conversion units 12a and 12b receive light that has passed through different regions of the optical system, and perform pupil division. Phase difference data (phase difference information) can be obtained by using pixel signals based on charges photoelectrically converted by the photoelectric conversion unit 12a and pixel signals based on charges photoelectrically converted by the photoelectric conversion unit 12b. Phase difference data can be used to perform phase difference AF (autofocus).

[0180] Pixels P each having a cell C including the photoelectric conversion units 12 a and 12 b may be repeatedly provided over the entire imaging surface of the imaging device 1, i.e., the entire pixel unit 100. In this case, phase difference data can be obtained over the entire imaging surface of the imaging device 1, enabling highly accurate autofocusing.

[0181] Each of the cells C of the pixel Pr, pixels Pg1, Pg2, and pixel Pb may have two or more photoelectric conversion units 12. For example, each of the cells C1 to C4 may be configured to include four photoelectric conversion units 12. Note that in the pixel unit 100, pixels P having cells C including a plurality of photoelectric conversion units 12 may be provided discretely.

[0182] 19, 20A, 20B, and 20C are diagrams for explaining another example configuration of an imaging device according to Modification 3. Fig. 20A shows an example of a cross-sectional configuration of the imaging device taken along line A-A' shown in Fig. 19. Fig. 20B shows an example of a cross-sectional configuration of the imaging device taken along line B-B' shown in Fig. 19. Furthermore, Fig. 20C shows an example of a cross-sectional configuration of the imaging device taken along line CC' shown in Fig. 19.

[0183] The inter-pixel isolation portion 30 may have a portion 31 and a portion 32 provided between the photoelectric conversion portion 12a and the photoelectric conversion portion 12b, as in the example shown in FIG. 19 etc. The portion 31 and the portion 32 are isolation regions provided between the adjacent photoelectric conversion portion 12a and the photoelectric conversion portion 12b, respectively. As an example, the portion 31 and the portion 32 have a shape extending in the Y-axis direction in a plan view. For example, as in the example shown in FIG. 19 , the portion 32 is provided so as to be aligned with the portion 31 in the Y-axis direction.

[0184] 21 and 22 are diagrams illustrating another example configuration of an imaging device according to Modification 3. Also, Fig. 22 shows an example cross-sectional configuration of the imaging device taken along line A-A' shown in Fig. 21. The imaging device 1 may have an overflow path 15 provided between adjacent photoelectric conversion units 12. The overflow path 15 may be provided adjacent to the photoelectric conversion units 12.

[0185] 21 and 22 , overflow path 15 is formed in semiconductor layer 10 between photoelectric conversion unit 12a and photoelectric conversion unit 12b. Overflow path 15 is a region formed using impurities, for example, an n-type semiconductor region. Overflow path 15 is formed, for example, between portion 31 and portion 32 so as to contact photoelectric conversion unit 12a and photoelectric conversion unit 12b. Note that overflow path 15 may also be formed of a p-type semiconductor region.

[0186] In the imaging device 1, the overflow path 15 is provided, so that overflowed charges can be transferred (moved) between the photoelectric conversion unit 12 a and the photoelectric conversion unit 12 b. For example, even if charges exceed the amount of charge (saturation charge amount) that can be stored in the photoelectric conversion unit 12 a, the charges that have overflowed from the photoelectric conversion unit 12 a can be stored in the photoelectric conversion unit 12 b.

[0187] 23A and 23B are diagrams for explaining a configuration example of an imaging device according to Modification 4. Structures 51 serving as nanostructures (microstructures) may be periodically arranged in the optical layer 70. For example, as in the example shown in FIG. 23A , the structures 51 may be arranged at the intersections of a grid of dashed lines arranged at equal intervals.

[0188] 23B , the structures 51 may be provided on the diagonal line D1 or D2 of the pixel P. The diagonal lines D1 and D2 can also be considered as axes of symmetry. By arranging the structures 51 in this manner, it is possible to ensure the symmetry of the point spread function (PSF).

[0189] (2-5. Modification 5) FIG. 24 is a diagram illustrating an example of the configuration of an imaging device according to Modification 5. The imaging device 1 may have a multi-layer (multi-stage) structure 51. The optical layer 70 of the imaging device 1 has, for example, a plurality of structures (structures 51a and 51b in the example shown in FIG. 24) stacked on top of each other. The element region 60 of each pixel P is provided with a first-stage structure 51a and a second-stage structure 51b.

[0190] The optical layer 70 includes a first optical layer 171 (first layer) including structures 51 a and members 55 a, and a second optical layer 172 (second layer) including structures 51 b and members 55 b. The second optical layer 172 is stacked on the first optical layer 171. The structures 51 a and 51 b each have a columnar (pillar) shape, for example.

[0191] The structures 51a and the members 55a may be made of materials having different refractive indices. The structures 51b and the members 55b may be made of materials having different refractive indices. The shapes and numbers of the structures 51a and 51b are not limited to the illustrated example and may be changed as appropriate.

[0192] In the imaging device 1 according to this modification, the optical layer 70 having multiple layer structures (e.g., structures 51a and 51b) can appropriately guide light to each cell C. The multiple-stage metasurface element can efficiently guide light in any wavelength range to the photoelectric conversion unit 12. It is possible to realize an imaging device 1 with good optical characteristics.

[0193] 25A, 25B, and 26A to 26C are diagrams for explaining a configuration example of an imaging device according to Modification 5. Fig. 25A shows a layout example of the second optical layer 172 of the optical layer 70, and Fig. 25B shows a layout example of the first optical layer 171 of the optical layer 70. Note that Fig. 24 corresponds to the configuration example in the direction of line A-A' shown in Figs. 25A and 25B.

[0194] 26A to 26C show examples of electric field intensity distributions on the surface 11S1 of the semiconductor layer 10. Fig. 26A shows an example of the electric field intensity of light in the red wavelength range among light incident via the optical layer 70. Fig. 26B shows an example of the electric field intensity of light in the green wavelength range, and Fig. 26C shows an example of the electric field intensity of light in the blue wavelength range.

[0195] In the imaging device 1 according to this modification, the optical layer 70 can appropriately guide light to each cell C (cells C1 to C4) of pixels Pr, Pg1, Pg2, and Pb, as in the example shown in Figures 26A to 26C. The electric field strength in each of cells C1 to C4 can be strengthened (raised), and light can be efficiently guided to the photoelectric conversion units 12 of cells C1 to C4. This makes it possible to effectively suppress a decrease in resolution.

[0196] (2-6. Modification 6) FIG. 27 is a diagram illustrating a configuration example of an imaging device according to Modification 6. As in the example shown in FIG. 27, the imaging device 1 may have anti-reflection films 45a and 45b. The anti-reflection film 45b (reflection suppression film) is provided on the side of the structure 51 on which light is incident. The anti-reflection film 45b is provided so as to cover, for example, the multiple structures 51, and reduces (suppresses) reflection.

[0197] The antireflection film 45a is provided on the side of the structure 51 opposite to the side on which light is incident. In the example shown in Fig. 27, the antireflection film 45a is provided between the spacer layer 90 and the structure 51. The antireflection films 45a and 45b are made of, for example, a material having a refractive index different from that of the structure 51. The antireflection films 45a and 45b can also be said to be part of the optical layer 70.

[0198] Fig. 28 is a diagram illustrating another example configuration of an imaging device according to Modification 6. As in the example shown in Fig. 28, the imaging device 1 may have antireflection films 45a to 45c. The antireflection film 45c is provided on the side of the structure 51b on which light is incident. The antireflection films 45a to 45c are made of an insulating material, such as silicon oxide or silicon nitride, for example.

[0199] The anti-reflection films 45a to 45c may be made of the same material or different materials. The anti-reflection films 45a, 45b, and 45c may have different refractive indices. The imaging device 1 may be configured to include only one or two of the anti-reflection films 45a to 45c.

[0200] (2-7. Modification 7) Figures 29A and 29B are diagrams for explaining an example of the configuration of an imaging device according to Modification 7. Figure 29B shows an example of the cross-sectional configuration in a region where the distance from the center of the pixel unit 100 (pixel array), i.e., the image height, is higher than in the case of Figure 29A. In the central region of the pixel unit 100, the pixel P is configured, for example, as shown in Figure 29A.

[0201] For example, light from an optical lens is incident almost perpendicularly on the central portion of the pixel unit 100 of the imaging device 1. Light is incident obliquely on the peripheral portion located outside the central portion, i.e., on the region farther from the center of the pixel unit 100, as shown by the example schematically indicated by the arrows in Fig. 29B. In the imaging device 1, the element region 60 having the structures 51 can be configured to differ depending on the distance from the center of the pixel unit 100, i.e., the image height.

[0202] The element region 60 having the plurality of structures 51 is disposed, for example, shifted toward the center of the pixel unit 100 with respect to the photoelectric conversion unit 12. In the example shown in Fig. 29B, the element region 60 is provided shifted to the right with respect to the photoelectric conversion unit 12 of the pixel P. The center of the element region 60 of the pixel P is located closer to the center of the pixel unit 100 than the center of the photoelectric conversion unit 12 of that pixel P.

[0203] In the pixel unit 100 of the imaging device 1, the positions of the structures 51, the positions of the element regions 60, etc. are adjusted according to the image height, allowing for appropriate pupil correction. This makes it possible to suppress a decrease in the amount of light incident on the photoelectric conversion unit 12 of each pixel P, and to suppress a decrease in sensitivity to incident light. It is possible to appropriately guide light to the photoelectric conversion unit 12, preventing a decrease in resolution.

[0204] (2-8. Modification 8) FIG. 30 is a diagram illustrating an example configuration of an imaging device according to Modification 8. The spacer layer 90 may be made up of a plurality of members, for example, a first member 91 and a second member 92. The first member 91 and the second member 92 are made using materials having different refractive indices. By configuring the spacer layer 90 with the first member 91 and the second member 92, it is possible to improve the light-collecting performance and realize a low-profile imaging device 1.

[0205] (2-9. Modification 9) In the above-described embodiment and modification, examples of pixel arrangements have been described, but the pixel arrangement is not limited to the above-described examples. For example, as shown in Fig. 31A or 31B , in the imaging device 1, pixel Pr, pixel Pg1, pixel Pg2, and pixel Pb may each be arranged in 2 × 2 pixel units.

[0206] For example, four adjacent pixels Pr, four adjacent pixels Pg1, four adjacent pixels Pg2, and four adjacent pixels Pb may be arranged repeatedly in the pixel section 100 (pixel array) of the imaging device 1. It can also be said that the pixels Pr, Pg1, Pg2, and Pb are each periodically arranged in 2 rows and 2 columns.

[0207] Each cell C (e.g., cells C1 to C4) of pixel P may have multiple photoelectric conversion units 12, for example, photoelectric conversion unit 12a and photoelectric conversion unit 12b as shown in FIG. 31B. Each of cells C1 to C4 of pixel Pr, pixels Pg1, Pg2, and pixel Pb may have two or more photoelectric conversion units 12, for example, four photoelectric conversion units 12.

[0208] 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 video camera, a mobile phone with an imaging function, etc. Fig. 32 shows a schematic configuration of an electronic device 1000.

[0209] 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.

[0210] 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.

[0211] 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.

[0212] 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.

[0213] 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.

[0214] 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.

[0215] FIG. 33 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.

[0216] The vehicle control system 12000 includes a plurality of electronic control units connected via a communication network 12001. In the example shown in Fig. 33, 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.

[0217] 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.

[0218] 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.

[0219] 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.

[0220] 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.

[0221] 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.

[0222] 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.

[0223] 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.

[0224] 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.

[0225] The audio / video output unit 12052 transmits at least one of audio and video output signals to an output device capable of visually or audibly notifying information to vehicle occupants or the outside of the vehicle. In the example of Fig. 33, 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.

[0226] FIG. 34 is a diagram showing an example of the installation position of the imaging unit 12031.

[0227] In FIG. 34, the imaging unit 12031 includes imaging units 12101, 12102, 12103, 12104, and 12105.

[0228] 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.

[0229] 34 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.

[0230] 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.

[0231] 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.

[0232] 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.

[0233] 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.

[0234] 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.

[0235] (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.

[0236] FIG. 35 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.

[0237] 35 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.

[0238] 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.

[0239] 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.

[0240] 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.

[0241] 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.

[0242] 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.

[0243] 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.

[0244] 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.

[0245] 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.

[0246] 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.

[0247] 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.

[0248] 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.

[0249] FIG. 36 is a block diagram showing an example of the functional configuration of the camera head 11102 and the CCU 11201 shown in FIG.

[0250] 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.

[0251] 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.

[0252] 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.

[0253] 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.

[0254] 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.

[0255] 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.

[0256] 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.

[0257] 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.

[0258] 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 .

[0259] 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.

[0260] 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.

[0261] The image processing unit 11412 performs various image processing operations on the image signal, which is RAW data transmitted from the camera head 11102 .

[0262] 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.

[0263] 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.

[0264] 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.

[0265] 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.

[0266] 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.

[0267] 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.

[0268] 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.

[0269] 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.).

[0270] A photodetector according to one embodiment of the present disclosure includes a semiconductor layer, a first pixel having a first photoelectric conversion region and a second photoelectric conversion region provided in the semiconductor layer, and an optical layer provided above the semiconductor layer and having a plurality of first structures. The optical layer includes a first region corresponding to the first photoelectric conversion region and a second region corresponding to the second photoelectric conversion region. The optical layer focuses light of a first wavelength band incident on the first region onto the first photoelectric conversion region, and focuses light of the first wavelength band incident on the second region onto the second photoelectric conversion region. This makes it possible to realize a photodetector that can suppress a decrease in resolution.

[0271] Note that the effects described in this specification are merely examples and are not limited thereto, and other effects may be present. The present disclosure may also have the following configurations. (1) A photodetector comprising: a semiconductor layer; a first pixel having a first photoelectric conversion region and a second photoelectric conversion region provided in the semiconductor layer; and an optical layer provided above the semiconductor layer and having a plurality of first structures, wherein the optical layer includes a first region corresponding to the first photoelectric conversion region and a second region corresponding to the second photoelectric conversion region, and the optical layer focuses light of a first wavelength band incident on the first region onto the first photoelectric conversion region and focuses light of the first wavelength band incident on the second region onto the second photoelectric conversion region. (2) The photodetector described in (1), wherein, in a plan view, the area of ​​the first pixel and the light-receiving area of ​​the first region are substantially the same. (3) The photodetector described in (1) or (2), wherein light of the first wavelength band incident on the first region is not focused on the second photoelectric conversion region. (4) The photodetector according to any one of (1) to (3), wherein the first pixel has a first cell including the first photoelectric conversion region and a second cell including the second photoelectric conversion region, wherein the first photoelectric conversion region performs photoelectric conversion on light incident through the first region, and the second photoelectric conversion region performs photoelectric conversion on light incident through the second region. (5) The photodetector according to (4), wherein the first cell and the second cell are positioned adjacent to each other in a first direction, and the first region and the second region are positioned adjacent to each other in the first direction. (6) The photodetector according to (4) or (5), wherein the first region and the second region of the optical layer each focus light to a region away from a boundary between the first cell and the second cell. (7) The photodetector according to any one of (4) to (6), wherein the optical layer focuses light of the first wavelength band incident on the first region to a center of the first cell, and focuses light of the first wavelength band incident on the second region to a center of the second cell.(8) The pixel further includes a second pixel adjacent to the first pixel, wherein the first pixel and the second pixel have the first photoelectric conversion region and the second photoelectric conversion region, respectively; and the optical layer includes: the first region corresponding to the first photoelectric conversion region of the first pixel; the second region corresponding to the second photoelectric conversion region of the first pixel; a third region corresponding to the first photoelectric conversion region of the second pixel; and a fourth region corresponding to the second photoelectric conversion region of the second pixel; and the optical layer collects light of the first wavelength band incident on the first region to the first photoelectric conversion region of the first pixel, collects light of the first wavelength band incident on the second region to the second photoelectric conversion region of the first pixel, collects light of the second wavelength band incident on the third region to the first photoelectric conversion region of the second pixel, and collects light of the second wavelength band incident on the fourth region to the second photoelectric conversion region of the second pixel. The photodetector according to any one of (1) to (7). (9) The photodetector according to (8), wherein the second region includes at least a part of the third region. (10) The photodetector according to (8) or (9), further comprising a third pixel adjacent to the second pixel, wherein the third pixel has the first photoelectric conversion region and the second photoelectric conversion region, and the optical layer includes a fifth region corresponding to the first photoelectric conversion region of the third pixel and a sixth region corresponding to the second photoelectric conversion region of the third pixel, and the optical layer collects light of a third wavelength incident on the fifth region onto the first photoelectric conversion region of the third pixel, and collects light of the third wavelength incident on the sixth region onto the second photoelectric conversion region of the third pixel. (11) The photodetector according to (10), wherein the fourth region includes at least a part of the fifth region. (12) The photodetector according to any one of (1) to (11), further comprising a filter provided above the first photoelectric conversion region and the second photoelectric conversion region between the optical layer and the semiconductor layer, the filter transmitting light of the first wavelength band. (13) The photodetector according to any one of (1) to (12), further comprising a light-shielding member provided in the semiconductor layer between the first photoelectric conversion region and the second photoelectric conversion region.(14) The photodetector according to any one of (1) to (13), further comprising a spacer layer provided between the optical layer and the semiconductor layer. (15) The photodetector according to any one of (1) to (14), further comprising an anti-reflection film provided above the first structures or below the first structures. (16) The photodetector according to any one of (1) to (15), wherein a plurality of the first structures are arranged in the optical layer so as to be aligned in a first direction. (17) The photodetector according to any one of (1) to (16), wherein the first structures have a columnar shape. (18) The photodetector according to any one of (1) to (17), wherein the optical layer has a first member provided around the first structures, and wherein the first member has a refractive index different from that of the first structures. (19) The photodetector according to any one of (1) to (18), wherein the optical layer includes a first layer including the plurality of first structures and a second layer including a plurality of second structures and stacked on the first layer. (20) The photodetector according to any one of (1) to (19), wherein the first pixel includes a plurality of the first photoelectric conversion regions and a plurality of the second photoelectric conversion regions. (21) An electronic device comprising: an optical system; and a photodetector that receives light transmitted through the optical system, wherein the photodetector has: a semiconductor layer; a first pixel having a first photoelectric conversion region and a second photoelectric conversion region provided in the semiconductor layer; and an optical layer that is provided above the semiconductor layer and has a plurality of first structures, wherein the optical layer includes a first region corresponding to the first photoelectric conversion region and a second region corresponding to the second photoelectric conversion region, and the optical layer focuses light of a first wavelength band that is incident on the first region onto the first photoelectric conversion region, and focuses light of the first wavelength band that is incident on the second region onto the second photoelectric conversion region.

[0272] This application claims priority based on Japanese Patent Application No. 2024-093347, filed on June 7, 2024, in the Japan Patent Office, the entire contents of which are incorporated herein by reference.

[0273] Those skilled in the art will recognize that various modifications, combinations, subcombinations, and variations may occur depending on design requirements and other factors, and are intended to be within the scope of the appended claims and their equivalents.

Claims

1. A photodetector comprising: a semiconductor layer; a first pixel having a first photoelectric conversion region and a second photoelectric conversion region provided in the semiconductor layer; and an optical layer provided above the semiconductor layer and having a plurality of first structures, wherein the optical layer includes a first region corresponding to the first photoelectric conversion region and a second region corresponding to the second photoelectric conversion region, and the optical layer focuses light of a first wavelength band incident on the first region onto the first photoelectric conversion region, and focuses light of the first wavelength band incident on the second region onto the second photoelectric conversion region.

2. The photodetector according to claim 1, wherein the area of ​​the first pixel and the light receiving area of ​​the first region are substantially the same in plan view.

3. The photodetector according to claim 1, wherein light in the first wavelength band incident on the first region is not focused on the second photoelectric conversion region.

4. The photodetector according to claim 1, wherein the first pixel has a first cell including the first photoelectric conversion region and a second cell including the second photoelectric conversion region, the first photoelectric conversion region photoelectrically converts light incident through the first region, and the second photoelectric conversion region photoelectrically converts light incident through the second region.

5. The photodetector device according to claim 4, wherein the first cell and the second cell are positioned adjacent to each other in a first direction, and the first region and the second region are positioned adjacent to each other in the first direction.

6. The photodetector according to claim 4, wherein the first region and the second region of the optical layer each focus light in a region away from the boundary between the first cell and the second cell.

7. The photodetector according to claim 4, wherein the optical layer focuses light of the first wavelength band incident on the first region at the center of the first cell, and focuses light of the first wavelength band incident on the second region at the center of the second cell.

8. The photodetector according to claim 1, further comprising a second pixel adjacent to the first pixel, wherein the first pixel and the second pixel have the first photoelectric conversion region and the second photoelectric conversion region, respectively; the optical layer includes: the first region corresponding to the first photoelectric conversion region of the first pixel; the second region corresponding to the second photoelectric conversion region of the first pixel; a third region corresponding to the first photoelectric conversion region of the second pixel; and a fourth region corresponding to the second photoelectric conversion region of the second pixel; and the optical layer focuses light of the first wavelength band incident on the first region onto the first photoelectric conversion region of the first pixel, focuses light of the first wavelength band incident on the second region onto the second photoelectric conversion region of the first pixel, focuses light of the second wavelength band incident on the third region onto the first photoelectric conversion region of the second pixel, and focuses light of the second wavelength band incident on the fourth region onto the second photoelectric conversion region of the second pixel.

9. The photodetector device according to claim 8, wherein the second region includes at least a portion of the third region.

10. The photodetector according to claim 8, further comprising a third pixel adjacent to the second pixel, the third pixel having the first photoelectric conversion region and the second photoelectric conversion region, the optical layer including a fifth region corresponding to the first photoelectric conversion region of the third pixel and a sixth region corresponding to the second photoelectric conversion region of the third pixel, and the optical layer focusing light of a third wavelength incident on the fifth region onto the first photoelectric conversion region of the third pixel, and focusing light of the third wavelength incident on the sixth region onto the second photoelectric conversion region of the third pixel.

11. The photodetector device according to claim 10, wherein the fourth region includes at least a part of the fifth region.

12. The photodetector according to claim 1, further comprising a filter that transmits light in the first wavelength band and is provided above the first photoelectric conversion region and the second photoelectric conversion region between the optical layer and the semiconductor layer.

13. The photodetector according to claim 1, further comprising an inter-pixel separator provided in the semiconductor layer between the first photoelectric conversion region and the second photoelectric conversion region.

14. The photodetector device according to claim 1, further comprising a spacer layer provided between the optical layer and the semiconductor layer.

15. The photodetector according to claim 1, further comprising an anti-reflection film provided on or under the first structure.

16. The photodetector according to claim 1, wherein the plurality of first structures are arranged in the optical layer in a first direction.

17. The photodetector according to claim 1, wherein the first structure has a columnar shape.

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

19. The photodetector device according to claim 1, wherein the optical layer comprises a first layer including the plurality of first structures, and a second layer including a plurality of second structures and stacked on the first layer.

20. The photodetector according to claim 1, wherein the first pixel includes a plurality of the first photoelectric conversion regions and a plurality of the second photoelectric conversion regions.

21. An electronic device comprising: an optical system; and a photodetector that receives light that has passed through the optical system, wherein the photodetector has: a semiconductor layer; a first pixel having a first photoelectric conversion region and a second photoelectric conversion region provided in the semiconductor layer; and an optical layer that is provided above the semiconductor layer and has a plurality of first structures, wherein the optical layer includes a first region corresponding to the first photoelectric conversion region and a second region corresponding to the second photoelectric conversion region, and the optical layer focuses light of a first wavelength band that is incident on the first region onto the first photoelectric conversion region, and focuses light of the first wavelength band that is incident on the second region onto the second photoelectric conversion region.

Images