Solid-state imaging device and electronic apparatus

Abstract

[Problem] To suppress crosstalk between pixels. [Solution] A solid-state imaging device according to the present invention comprises pixels. The pixels have a photoelectric conversion layer and a first diffusion region. The photoelectric conversion layer receives incident light and converts the received light into carriers based on the intensity of the light. The first diffusion region acquires the carriers produced from the light at the photoelectric conversion layer. The pixels also have second diffusion regions that acquire the carriers produced at the photoelectric conversion layer. The second diffusion regions are next to adjacent pixels at positions that are closer to the first diffusion region of the relevant pixel than the first diffusion regions of the adjacent pixels. The first diffusion region is formed deeper into the photoelectric conversion layer than the second diffusion regions.

Description

Solid-state imaging device and electronic device

[0001] The present disclosure relates to a solid-state imaging device and an electronic device.

[0002] Centering on receiving light in the infrared band, InGaAs sensors have been widely used. Generally, an InGaAs sensor has a stacked structure of n+InP / n-InGaAs / n-InP. Zn, which is a p-type impurity, is diffused for each pixel on the n-InP side to form a p+ region, and a pn junction region on a one-dimensional array pattern is formed. In this formation, a separation structure is often not arranged between adjacent pixels.

[0003] In a configuration without this separation structure between pixels, there is an inherent problem that electrical crosstalk to adjacent pixels easily occurs and the resolution decreases. In addition, due to variations in the depth of the p-type diffusion layer, the carrier recovery efficiency varies pixel by pixel, and variations in output occur between adjacent pixels when light is incident, raising the concern of defective pixels.

[0004] Japanese Unexamined Patent Application Publication No. 2009-99907

[0005] Therefore, one of the non-limiting problems to be solved by the embodiments of the present disclosure is to suppress crosstalk between pixels. The problems to be solved by the embodiments of the present disclosure can also be, as some further non-limiting examples, problems corresponding to the effects described in the embodiments. That is, the problems corresponding to any at least one of the effects described in the description of the embodiments of the present disclosure can be the problems to be solved in the present disclosure.

[0006] According to one embodiment, the solid-state imaging device includes a pixel. The pixel includes a photoelectric conversion layer and a first diffusion region. The photoelectric conversion layer receives incident light and converts it into carriers based on the received light intensity. The first diffusion region acquires the carriers converted in light by the photoelectric conversion layer. This pixel further has a second diffusion region between it and an adjacent pixel, located closer to the first diffusion region of that pixel than to the first diffusion region of the adjacent pixel, which acquires the carriers converted in the photoelectric conversion layer. The first diffusion region is formed to a deeper position in the photoelectric conversion layer than the second diffusion region. Furthermore, the electronic device according to one embodiment includes the above configuration and further includes a signal processing circuit for processing the signal output from the pixel.

[0007] The photoelectric conversion layer may be a layer formed containing n-type InGaAs.

[0008] The first diffusion region and the second diffusion region may be layers in which p-type impurities are diffused into the photoelectric conversion layer and the n-type InP layer.

[0009] The first electrode, which propagates carriers from the first diffusion region, may be formed in contact with the photoelectric conversion layer.

[0010] The second diffusion region may further be formed in a layer of another compound formed on the side of the InP layer opposite to the photoelectric conversion layer, and the second electrode that propagates carriers from the second diffusion region may be formed in contact with the layer of the other material.

[0011] Multiple second diffusion regions may be arranged separately for each pixel.

[0012] The second diffusion region may be arranged so as to surround the first diffusion region for each pixel.

[0013] The pixels may be transferred to a floating diffusion layer that shares carriers output from the first diffusion region and the second diffusion region, and a signal value based on the received light intensity may be acquired in a subsequent circuit.

[0014] A transfer gate may be shared for transferring carriers output from the first diffusion region and the second diffusion region to the floating diffusion layer.

[0015] The transfer gate that transfers carriers output from the first diffusion region to the floating diffusion layer and the transfer gate that transfers carriers output from the second diffusion region to the floating diffusion layer may be different.

[0016] The pixel may transfer the carriers output from the first diffusion region and the second diffusion region to separate floating diffusion layers, and a signal value based on the received light intensity may be obtained by adding the signal values ​​acquired from each diffusion layer in a subsequent circuit.

[0017] The photoelectric conversion layer may be a layer formed by including at least one of n-type InGaAsP, InAlAs, GaAsSb, or InGaAsSb.

[0018] A schematic block diagram showing a partial, non-limiting example of a solid-state imaging device according to one embodiment. A schematic block diagram showing a partial, non-limiting example of a solid-state imaging device according to one embodiment. A schematic cross-sectional (perspective) view showing a partial, non-limiting example of a pixel of a solid-state imaging device according to one embodiment. A schematic cross-sectional (perspective) view showing a partial, non-limiting example of a pixel of a solid-state imaging device according to one embodiment. A schematic cross-sectional (perspective) view showing a partial, non-limiting example of a pixel of a solid-state imaging device according to one embodiment. A schematic top view showing a partial, non-limiting example of a pixel of a solid-state imaging device according to one embodiment. A schematic top view showing a partial, non-limiting example of a pixel of a solid-state imaging device according to one embodiment. A schematic top view showing a partial, non-limiting example of a pixel of a solid-state imaging device according to one embodiment. A schematic top view showing a partial, non-limiting example of a pixel of a solid-state imaging device according to one embodiment. A schematic circuit diagram showing an example of a pixel circuit according to one embodiment. A schematic circuit diagram showing an example of a pixel circuit according to one embodiment. A schematic cross-sectional view showing an example of a pixel manufacturing process according to one embodiment. A schematic cross-sectional view illustrating an example of the pixel manufacturing process according to one embodiment. A schematic cross-sectional view illustrating an example of the pixel manufacturing process according to one embodiment. A schematic cross-sectional view illustrating an example of the pixel manufacturing process according to one embodiment. A schematic cross-sectional view illustrating an example of the pixel manufacturing process according to one embodiment. A schematic cross-sectional view illustrating an example of the pixel manufacturing process according to one embodiment. A schematic cross-sectional view illustrating an example of the pixel manufacturing process according to one embodiment. A schematic cross-sectional view illustrating an example of the pixel manufacturing process according to one embodiment. A schematic cross-sectional view illustrating an example of the pixel manufacturing process according to one embodiment. A schematic cross-sectional view illustrating an example of the pixel manufacturing process according to one embodiment. A schematic cross-sectional view illustrating an example of the pixel manufacturing process according to one embodiment. A schematic cross-sectional view illustrating an example of the pixel manufacturing process according to one embodiment. A schematic cross-sectional view illustrating an example of the pixel manufacturing process according to one embodiment. A schematic cross-sectional view illustrating an example of the pixel manufacturing process according to one embodiment. A schematic cross-sectional view illustrating an example of the pixel manufacturing process according to one embodiment. A schematic cross-sectional view illustrating an example of the pixel manufacturing process according to one embodiment.A schematic cross-sectional view showing an example of a pixel manufacturing process according to one embodiment. A block diagram showing an example of a general configuration of a vehicle control system. An explanatory diagram showing an example of the installation positions of the external information detection unit and the imaging unit.

[0019] The embodiments of this disclosure will now be described with reference to the drawings. The drawings are for illustrative purposes only, and the shape, size, or size ratio of each component in the actual device does not need to be exactly as shown in the drawings. Furthermore, the drawings are simplified, so any other components necessary for implementation should be appropriately provided in addition to those shown in the drawings.

[0020] This disclosure describes embodiments in the following order: 1. Solid-state imaging device 2. Photoelectric conversion unit 3. Pixel circuit 4. Process 5. Application examples

[0021] <1. Solid-State Imaging Devices>

[0022] Figure 1 is a schematic block diagram showing at least a part of a solid-state imaging device according to one embodiment. The solid-state imaging device 1 comprises a pixel array 10, a control circuit 12, a first scanning circuit 14, a second scanning circuit 16, and a signal processing circuit 18. The solid-state imaging device 1 receives light including the infrared band, for example, to acquire information such as images and videos (hereinafter referred to as "images, etc."). In the embodiments of this disclosure, the reception of light including the infrared band is mainly performed, but it should be noted that the invention is not limited to this and can be applied to other forms having a similar structure.

[0023] Furthermore, while some examples show n-type / p-type semiconductors, the material is not limited to these, and any semiconductor that conducts appropriate carriers can be used. Similarly, while examples of materials are shown that are not limited, please note that it is possible to substitute them with materials that have similar properties, either individually or in combination. The concepts of "individual or combination" include both the selection of a single or combination of materials to form a single layer, electrode, etc., and the selection of materials that produce equivalent properties as a combination of adjacent regions, etc. Please note that the interpretation should be made depending on the context.

[0024] The pixel array 10 is a region that forms a light-receiving area, and a plurality of pixels 100 are arranged thereon. In the pixel array 10, the pixels 100 are arranged in a two-dimensional array along, for example, a first direction (line direction) and a second direction (column direction) intersecting the first direction. The pixel array 10 may, for example, acquire information such as an image using all the pixels 100 that are arranged thereon. As another example, pixels 100 located at the periphery of the pixel array 10 may be set up as dummy pixels that do not directly receive light, and a light-receiving area may be established, and information such as an image may be acquired using the pixels 100 belonging to that light-receiving area.

[0025] Each pixel 100 receives incident light in the pixel array 10 or the light-receiving area described above, generates a signal corresponding to the intensity of the received light, and outputs it to the signal processing circuit 18. Based on the output from each pixel 100, the signal processing circuit 18 generates information such as an image.

[0026] The control circuit 12 is a circuit that controls the output of pixels 100 in the pixel array 10. The control circuit 12 may also be a circuit that performs other controls of the solid-state imaging device 1. For example, the control circuit 12 controls pixels 100 via the first scanning circuit 14 and the second scanning circuit 16. The control circuit 12 can also perform control based on information obtained from the signal processing circuit 18, etc.

[0027] The first scanning circuit 14 is a circuit that controls the output of pixels 100 in the pixel array 10. The first scanning circuit 14 performs control for each pixel 100 belonging to the same first direction in the pixel array 10, for example, via a signal line 144 that is commonly connected to pixels 100 belonging to the same first direction in the pixel array 10. The first scanning circuit 14 outputs a signal that makes pixels 100 belonging to the same line drivable, for example, and sets the pixels 100 that are selected to be drivable in a line. The first scanning circuit 14 selects a line to be made drivable by a command from the control circuit 12, for example.

[0028] The second scanning circuit 16 is a circuit that controls the output of pixels 100 in the pixel array 10. The second scanning circuit 16 performs control for each pixel 100 belonging to the same second direction in the pixel array 10, for example, via a signal line 162 that is commonly connected to pixels 100 belonging to the same second direction in the pixel array 10. The second scanning circuit 16 performs control by outputting a drive signal for the pixel 100, for example, causing the pixel 100 belonging to the line selected by the first scanning circuit 14 to output a signal based on the intensity of the received light to the signal processing circuit 18.

[0029] The signal processing circuit 18 acquires and outputs image data based on the signals output from each pixel 100 via the signal line 180. The signal processing circuit 18 may also include, for example, an analog-to-digital converter (ADC) that converts the analog signals output from the pixels 100 into digital signals. In addition, the signal processing circuit 18 may perform image processing, recognition processing, etc., on the image data generated based on the acquired signals and output the result.

[0030] The solid-state imaging device 1 outputs image data based on the intensity of light received at the pixel 100 using this configuration. Note that the solid-state imaging device 1 does not necessarily need to be configured with pixels 100 arranged in a two-dimensional array as shown in Figure 1.

[0031] Figure 2 is a schematic block diagram showing a part of a solid-state imaging device 1 according to one embodiment. As shown in this figure, the solid-state imaging device 1 may have pixels 100 arranged in a line shape. That is, the solid-state imaging device 1 may be a line sensor that acquires a line-shaped signal by receiving light at pixels 100 arranged in a one-dimensional line segment shape, rather than acquiring data such as an image based on signals from pixels 100 arranged in a two-dimensional array in a region. In this case, the first scanning circuit 14, as shown in the figure, is not an essential component.

[0032] The solid-state imaging device 1 is not limited to the configuration shown in Figure 2, and may be a line sensor in which multiple pixels 100 are arranged in a line as a pixel array 10. Even when operating as a line sensor, it can operate as a more accurate line sensor by appropriately acquiring the output from the pixels 100 belonging to multiple lines. In this case, the pixel array 10 may have two or more lines in a configuration similar to that shown in Figure 2, or it may further include a first scanning circuit 14.

[0033] In the following, we will describe an example in which pixels 100 are arranged in a two-dimensional array as shown in Figure 1. However, please note that a similar configuration can be used for line sensors, for example, by using the same form or by omitting the transistor for line selection.

[0034] <2. Photoelectric Conversion Unit>

[0035] Next, the surrounding structure centered on the photoelectric conversion unit will be described as an embodiment of the present disclosure. First, the photoelectric conversion layer, the surrounding diffusion layer, electrodes, etc. will be described using the cross-sectional structure of pixel 100.

[0036] (First Embodiment)

[0037] Figure 3 is a schematic cross-sectional or perspective view showing an example of the configuration of a pixel 100 according to one embodiment. The pixel 100 comprises, for example, a transparent electrode 102, an n+InP layer 104, a photoelectric conversion layer 106, an n-InP layer 108, a wiring layer 110, and a substrate 112, in order from the light incident surface. In the following drawings, the illustration and description of oxide films and the like, which are not essential features in this disclosure, have been omitted. However, it should be noted that appropriate insulators such as oxide films are provided in necessary areas, such as around the electrodes, at the boundary between the electrodes and the semiconductor, and at the boundary between the wiring and the semiconductor.

[0038] The transparent electrode 102 may be an electrode made of a transparent thin film formed of, for example, indium tin oxide (ITO). The transparent electrode 102 acts as an electrode that guides carriers generated in the photoelectric conversion layer 106 in the appropriate direction by applying an appropriate voltage, for example.

[0039] The n+InP layer 104 is a layer used as a substrate for forming the photoelectric conversion layer 106. After the sensor is formed, the n+InP layer 104 is positioned so as to be in contact with the side opposite to the incident surface of the transparent electrode 102.

[0040] The photoelectric conversion layer 106 is a layer formed from a material that converts incident light into electricity, and is a layer that generates carriers based on the intensity of the incident light. The photoelectric conversion layer 106 is positioned in contact with the n+InP layer 104 on the side opposite to the incident surface. The photoelectric conversion layer 106 is formed from, for example, gallium indium arsenide (InGaAs), which efficiently converts light in the infrared band. The photoelectric conversion layer 106 may be formed as an n-type InGaAs layer. The photoelectric conversion layer 106 is not limited to this and can be formed from, for example, InGaAsP, InAlAs, GaAsSb, InGaAsSb, etc.

[0041] The n-InP layer 108 is a layer formed on the side opposite to the incident surface of the photoelectric conversion layer 106. The n-InP layer 108 is, for example, an epitaxial layer formed on the upper surface of the photoelectric conversion layer 106 during the production process. Through the n-InP layer 108, a diffusion region is formed in the photoelectric conversion layer 106, and by electrically connecting this diffusion region and the electrode, the carriers generated in the photoelectric conversion layer 106 are appropriately propagated to the readout circuit.

[0042] The wiring layer 110 is a layer in which a carrier propagation circuit and a readout circuit are arranged. The wiring layer 110 is formed by including, for example, an insulating film, and by arranging electrodes, wirings, etc. in this insulating film, the carriers generated in the photoelectric conversion layer 106 are appropriately propagated.

[0043] The wiring layer 110 can have a configuration in which the wirings in the carrier propagation circuit and the readout circuit formed by different manufacturing processes are joined and laminated by appropriate joining, for example, microbumps, joining of metal wirings, joining by via holes, etc. The wiring layer 110 can have a laminated structure, for example, at the location indicated by the broken line in the figure. It is not limited to this, and the wiring layer 110 may not have a laminated structure, or may have a structure of three or more layers.

[0044] The substrate 112 is a layer for forming other circuit configurations. Regarding the features in the present disclosure, the configuration of this substrate 112 does not particularly affect it, so details regarding this layer are omitted. The substrate 112 is where the wirings and elements of the circuit after the general readout circuit are formed.

[0045] In this configuration, as shown by the dotted line, the unit pixels are arranged without forming a pixel isolation film. Therefore, a configuration is required to appropriately propagate the carriers generated in the photoelectric conversion layer 106 to the readout circuit. This main configuration is the first diffusion region 120.

[0046] The first diffusion region 120 is a diffusion region formed in the photoelectric conversion layer 106 through the n-InP layer 108. The first diffusion region 120 is, for example, a p+-type diffusion region, and is formed by doping Zn in a selective region of the photoelectric conversion layer 106 and the n-InP layer 108. Without being limited thereto, the first diffusion region 120 can be formed by doping an appropriate p-type impurity into the photoelectric conversion layer 106 and the n-InP layer 108.

[0047] The first diffusion region 120 is a region that forms a light-receiving pixel provided for each pixel 100. That is, for example, the pixel 100 is formed centering on the first diffusion region 120.

[0048] The first electrode 140 is an electrode for propagating the carriers generated in the photoelectric conversion layer 106 collected by an electrical force in the first diffusion region 120 through a wiring. The first electrode 140 is formed, for example, so as to contact the n-InP layer 108 in which the first diffusion region 120 is formed.

[0049] The second diffusion region 122 is a diffusion region formed in the photoelectric conversion layer 106 through the n-InP layer 108. The second diffusion region 122 is, for example, a p+-type diffusion region, and is formed by doping Zn in a selective region of the photoelectric conversion layer 106 and the n-InP layer 108. Without being limited thereto, the second diffusion region 122 can be formed by doping an appropriate p-type impurity into the photoelectric conversion layer 106 and the n-InP layer 108.

[0050] In the pixel 100, the first diffusion region 120 mainly collects carriers, and the second diffusion region 122 subsidiarily collects carriers. For this reason, it is desirable that the first diffusion region 120 exists deeper (in FIG. 3, more upward) in the photoelectric conversion layer 106 than the second diffusion region 12 . Due to this depth difference, the first diffusion region 120 becomes the main diffusion region for collecting carriers in the pixel 100.

[0051] In this figure and other drawings, the size of the second diffusion region 122 is exaggerated for illustrative purposes. However, as a diffusion region for collecting carriers that cross the boundaries between pixels, it can be a region that is sufficiently shallower and formed over a narrower area than the first diffusion region 120.

[0052] The second diffusion region 122 is formed in a pixel 100 (for example, the pixel 100 in the center of the drawing) at a position closer to the first diffusion region 120 of the pixel 100 (the pixel 100 in the center of the drawing) than to the first diffusion region 120 of the adjacent pixel 100 (for example, the pixel 100 on the right side of the drawing). More preferably, the second diffusion region 122 is formed in the region of the pixel 100 at a position close to the boundary of the pixel 100 indicated by the dotted line.

[0053] The second diffusion region 122 is formed in pixel 100 as an auxiliary diffusion region for collecting carriers that the first diffusion region 120 could not collect in the region of pixel 100. That is, the second diffusion region 122 can function to prevent carriers that the first diffusion region 120 could not collect in pixel 100 from being collected in the first diffusion region 120 of adjacent pixels (which may include diagonally adjacent pixels), and to collect carriers generated in pixel 100 with higher precision in the same pixel 100.

[0054] Furthermore, it is desirable that the second diffusion region 122 be formed as a smaller region than the first diffusion region 120, in other words, as a region with a lower carrier collection capacity. Specifically, the second diffusion region 122 is formed as a smaller region (or a region with a lower p-type density) than the first diffusion region 120 of the adjacent pixel, preferably near the boundary between the adjacent pixel and the pixel 100.

[0055] The second electrode 142 is an electrode for propagating carriers generated in the photoelectric conversion layer 106, which are collected by electrical force in the second diffusion region 122, through the wiring. The second electrode 142 is formed, for example, so as to be in contact with the n-InP layer 108 on which the second diffusion region 122 is formed.

[0056] At least one of the first electrode 140 or the second electrode 142 transfers carriers generated in the photoelectric conversion layer 106 to a readout circuit in the wiring layer 110 via the connecting wiring 150. This transfer is propagated to the wiring 160, similar to a typical image sensor, and from this wiring 160, the carrier signal is appropriately transferred via a transfer gate to a floating diffusion layer or the like that converts it into a voltage signal. This is then converted into a digital signal corresponding to the intensity of light received by each pixel 100, generating image data and the like.

[0057] By forming the region as described above, it becomes possible to appropriately collect the carriers generated in the photoelectric conversion layer 106 at each pixel 100. The output from the second diffusion region 122 may be added together with the output from the first diffusion region 120 at the same pixel 100. By adding them together, it becomes possible to collect carriers generated by the intensity of light received in each region of the pixel 100 with higher precision, and as a result, it becomes possible to generate data with high-precision brightness values ​​such as images.

[0058] In Figure 3, the first diffusion region 120 and the second diffusion region 122 are formed in the photoelectric conversion layer 106 via the same diffusion layer, the n-InP layer 108, but are not limited to this.

[0059] (Second Embodiment)

[0060] Figure 4 is a schematic cross-sectional or perspective view showing an example of the configuration of a pixel 100 according to one embodiment. The basic configuration is the same as that of the pixel 100 shown in Figure 3. In this embodiment, the surface in contact with the first electrode 140 is the surface where the first diffusion region 120 of the photoelectric conversion layer 106 is formed, rather than the n-InP layer 108.

[0061] This configuration allows the depth of the main diffusion region for carrier collection to be greater than that of the diffusion region for suppressing crosstalk. As a result, it is possible to improve the carrier collection efficiency in the first diffusion region 120, while simultaneously suppressing the diffusion of carriers to adjacent pixels by the second diffusion region 122.

[0062] (Third embodiment)

[0063] Figure 5 is a schematic cross-sectional or perspective view showing an example of the configuration of a pixel 100 according to one embodiment. The basic configuration is the same as that of the pixel 100 shown in Figure 3. In this embodiment, an epicapital layer (for example, an n-InAlAs layer 114) made of a different material is selectively formed on the side opposite to the photoelectric conversion layer 106 in the n-InP layer 108 of the previously described embodiment, thereby controlling the depth of the first diffusion region 120 and the second diffusion region 122.

[0064] The n-InAlAs layer 114 is formed in a region of the n-InP layer 108 opposite to the incident surface side, excluding the region where the first diffusion region 120 is formed. The second diffusion region 122 is formed via this n-InAlAs layer 114. That is, the second diffusion region 122 is formed so as to reach into the photoelectric conversion layer 106 via the n-InAlAs layer 114 and the n-InP layer 108.

[0065] This embodiment, as with the second embodiment described above, makes it possible to more easily control the depth of the first diffusion region 120 and the second diffusion region 122.

[0066] (Fourth Embodiment)

[0067] Next, the two-dimensional arrangement of the first diffusion region 120 and the second diffusion region 122 will be described using a top view. Figure 6 is a schematic top view showing an example, not limited to, a part of the pixels of a solid-state imaging device according to one embodiment. Figures 3 to 5 may be shown as a front cross-sectional view of AA or a cross-sectional view of BB, for example.

[0068] As shown in this figure, it is desirable that the first diffusion region 120 be located, for example, near the center of the region of pixel 100. The second diffusion region 122 is located closer to the first diffusion region 120 belonging to the pixel 100 than to the first diffusion region 120 of the adjacent pixels of the pixel 100 to which the second diffusion region 122 belongs. The second diffusion region 122 can be located at the four corners of the region that forms each pixel 100.

[0069] The arrangement is not limited to this; for example, the arrangements shown in Figures 7 and 8 may also be used.

[0070] Thus, the configuration may involve multiple second diffusion regions 122 being separated and arranged within a single pixel 100.

[0071] (Fifth embodiment)

[0072] Figure 9 is a schematic top view showing a partial, not limited, example of pixels in a solid-state imaging device according to one embodiment. As shown in this figure, the second diffusion region 122 may be arranged to surround the first diffusion region 120 for each pixel 100.

[0073] In this figure, a rectangular second diffusion region 122 is shown, but it is not limited to this, and for example, a second diffusion region 122 of a circular shape may also be arranged.

[0074] <3. Pixel Circuit>

[0075] (Sixth Embodiment)

[0076] Next, a circuit diagram representing pixel 100 will be described. In this disclosure, the pixel circuit will mainly be described in terms of the arrangement of the first diffusion region 120 and the second diffusion region 122, but other than the first diffusion region 120 and the second diffusion region 122 being represented by separate light-receiving elements (e.g., photodiodes), it can take various forms. That is, the configuration of the floating diffusion region, reset transistor, amplification transistor, selection transistor, overflow gate, etc., can be any configuration as long as it does not contradict the spirit of this disclosure. Note that if the solid-state imaging device 1 is configured as a line sensor, the selection transistor may be omitted.

[0077] Figure 10 is a circuit diagram showing an example of a pixel circuit according to one embodiment. The pixel circuit comprises a first photodetector L1, a second photodetector L2, a capacitor C1, a transfer gate TRG, a capacitor Cfd, a reset transistor RST, an amplification transistor AMP, and a selection transistor SEL.

[0078] The first photodetector L1 represents the first diffusion region 120 in the circuit diagram and outputs a current corresponding to the carriers collected in the first diffusion region 120. The second photodetector L2 represents the second diffusion region 122 in the circuit diagram and outputs a current corresponding to the carriers collected in the second diffusion region 122. The amount of charge stored in the capacitor C1 changes in accordance with the outputs of the first photodetector L1 and the second photodetector L2, and a signal is accumulated in the capacitor C1 in accordance with the currents output from the first photodetector L1 and the second photodetector L2.

[0079] The transfer gate TRG is a gate that transfers signals corresponding to the outputs of the first photodetector L1 and the second photodetector L2 to the floating diffusion region FD at an appropriate timing. The gate of the transfer gate TRG is connected to the second scanning circuit 16 via, for example, one of the signal lines 162. The floating diffusion region FD converts the signal transferred from the transfer gate TRG into a voltage signal. This voltage signal is stored in the capacitor Cfd.

[0080] Depending on the configuration, capacitors C1 and Cfd may be omitted. Alternatively, a memory area may be provided between the transfer gate TRG and the floating diffusion region FD, and another transfer gate may be provided between this memory area and the floating diffusion region FD.

[0081] The reset transistor RST, the amplification transistor AMP, and the selection transistor SEL operate in a manner similar to that of a typical image sensor. For example, when the reset transistor RST is turned on at the appropriate time, the potential of the floating diffusion region FD is reset (discharging the capacitor Cfd), and when the selection transistor SEL is turned on at the appropriate time, a current corresponding to the voltage based on the light intensity applied to the amplification transistor AMP is output to the signal line VSL.

[0082] The gate of the reset transistor RST is connected to the second scanning circuit 16 via, for example, one of the signal lines 162 (a different path from the signal line connected to the gate of the transfer gate TRG). The gate of the selection transistor SEL is connected to the first scanning circuit 14 via, for example, signal line 144. The output from the selection transistor SEL is output to the signal processing circuit 18 in Figure 1 via signal line VSL, which is one of the signal lines 180.

[0083] In this way, the outputs from the first diffusion region 120 and the second diffusion region 122 are combined within the same pixel 100, and this combined signal can be transferred by the transfer gate TRG.

[0084] (Seventh Embodiment)

[0085] Figure 11 is a circuit diagram showing an example of a pixel circuit according to one embodiment. The pixel circuit basically has the same configuration as in Figure 10, but the output of the first photodetector L1 and the output of the second photodetector L2 are not directly connected.

[0086] The output from the first photodetector L1 is stored in capacitor C1 and transferred to the floating diffusion region FD via transfer gate TRG1. The output from the second photodetector L2 is stored in capacitor C2 and transferred to the floating diffusion region FD via transfer gate TRG2. By turning on transfer gates TRG1 and TRG2 at the same time, the signals from the outputs of the first photodetector L1 and the second photodetector L2 are transferred to the floating diffusion region FD and summed up.

[0087] In this way, the output from the first photodetector L1 and the output from the second photodetector L2 can be stored in separate regions. If multiple second photodetectors L2 are arranged in the same pixel 100, they may be configured to have a shared capacitor C2 and transfer gate TRG2, or each may have a separate capacitor and transfer gate.

[0088] (Eighth embodiment)

[0089] Figure 12 is a circuit diagram showing an example of a pixel circuit according to one embodiment. The pixel circuit basically has the same configuration as the embodiments described above, but each of the first photodetector L1 and the second photodetector L2 is provided with a pixel circuit without sharing the floating diffusion region FD. That is, the output from the first photodetector L1 is transferred to the floating diffusion region FD1 by the transfer gate TRG1 at an appropriate timing, and the output from the second photodetector L2 is transferred to a floating diffusion region FD2, which is different from the floating diffusion region FD1, by the transfer gate TRG2 at an appropriate timing.

[0090] In this configuration, the output from the first photodetector L1 and the output from the second photodetector L2 may be added together, for example, within the signal processing circuit 18 at an appropriate timing. As an example that is not limited, the signal processing circuit 18 may add them together as analog signals output from each and then perform AD conversion. As an example that is not limited, the signal processing circuit 18 may add the digital signals obtained by AD conversion of the analog signals output from each.

[0091] Furthermore, if multiple second photodetectors L2 are arranged in the same pixel 100, they may be configured to have a shared capacitor C2, a transfer gate TRG2, and a floating diffusion region FD2, or each may have a separate capacitor, a transfer gate, and a floating diffusion region.

[0092] (Ninth Embodiment)

[0093] Figure 13 is a circuit diagram showing an example of a pixel circuit according to one embodiment. In the sixth to eighth embodiments described above, the solid-state imaging device 1 can make the pixel signal more accurate depending on the carriers collected by the second diffusion region 122. However, in this embodiment, it is assumed that the collection by the first diffusion region 120 is sufficient, and the second diffusion region 122 is used only for crosstalk suppression.

[0094] As shown in this figure, the second photodetector L2 can also be configured to suppress crosstalk by directing the carriers collected by the second diffusion region 122 to, for example, the ground surface. For example, when the target of imaging is mainly bright objects, this configuration allows for the appropriate handling of carriers that may overflow.

[0095] Furthermore, if the first photodetector L1 of pixel 100 is equipped with an overflow gate, it is also possible to output the output from the second photodetector L2 via the overflow gate in conjunction with the overflow processing of the first photodetector L1.

[0096] <4. Process>

[0097] Next, the manufacturing process of the solid-state imaging device 1 according to this disclosure will be described. First, similar to a general InGaAs image sensor, n-InGaAs is formed by stacking n+InP on an n+InP substrate, and n-InP is formed on the upper surface thereon by epicapital growth. From this upper surface, diffusion regions relating to the first diffusion region 120 and the second diffusion region 122 are selectively generated.

[0098] In forming the pixel 100 according to the first embodiment, after the above process, as shown in Figure 14, an insulating film 116 and a resist 200 are sequentially formed on the upper surface of the n-InP layer 108 to form a resist 200 in a selective region. The insulating film 116 may be SiO2, for example, but is not limited to this example.

[0099] Next, as shown in Figure 15, trenches are formed in the insulating film 116 on the upper surface using the resist 200. These trenches are formed such that the area forming the second diffusion region 122 is narrower than the area forming the first diffusion region 120. The trenches may be formed by etching or other appropriate methods.

[0100] Next, as shown in Figure 16, by implanting impurity ions such as Zn+ (as an example, not limited to Zn+) from this top surface, a first diffusion region 120 and a second diffusion region 122 are formed. By selectively changing the width of the trenches formed, it is possible to create the first diffusion region 120 and the second diffusion region 122. Subsequently, by removing the resist, diffusion regions within InGaAs can be generated.

[0101] Next, a metal film 202 is formed as shown in Figure 17. The formation of the metal film 202 may be carried out, for example, by appropriate vapor deposition. The metal film 202 may be W, as an example, not limited to this.

[0102] Next, as shown in Figure 18, a resist 200 is selectively formed at the locations where the first electrode 140 and the second electrode 142 are formed.

[0103] Next, as shown in Figure 19, the first electrode 140 and the second electrode 142 are formed by selectively etching the metal film 202 using the resist 200 and then removing the resist. The width of the first electrode 140 and the second electrode 142 is determined using the insulating film 116 used when forming the first diffusion region 120 and the second diffusion region 122, respectively. Therefore, similar to how the first diffusion region 120 and the second diffusion region 122 were created, they are formed as electrodes of appropriate size so as to be in contact with the first diffusion region 120 and the second diffusion region 122, respectively.

[0104] Next, as shown in Figure 20, an insulating film 118 is formed on the upper surfaces of the first electrode 140, the second electrode 142, and the insulating film 116. On the upper surface of this insulating film 118, an insulating film that will become part of the wiring layer 110 is formed, as shown in Figure 21. The wiring layer 110 may be SiO2, for example, as an example, though not limited to this.

[0105] Then, as shown in Figure 22, trenches are formed in the insulating film formed by this wiring layer 110, and a metal such as Cu is formed within these trenches (not limited to this example), thereby forming wiring that enables electrical connection with a separately formed readout circuit.

[0106] Subsequently, wiring layers and the like, on which subsequent circuits including a separately formed readout circuit are arranged, are stacked using an appropriate method to form the layers from the photoelectric conversion layer to the readout circuit. After the readout circuit and the like are stacked, the n+InP layer 104 is placed with its top surface facing upwards, and a transparent electrode 102 made of ITO (as an example, not limited to ITO) is formed on the top surface of this n+InP layer 104, thereby mounting the pixel 100 shown in Figure 3.

[0107] In forming the pixel 100 according to the second embodiment, after the process shown in Figure 14, a resist 200 is selectively formed as shown in Figure 23 so that impurities are selectively diffused in the region where the second diffusion region 122 is formed, and a trench is formed in the insulating film 116 using this resist.

[0108] Subsequently, as shown in Figure 24, the resist 200 is selectively formed again on the upper surface, and as shown in Figure 25, a trench is selectively formed in the region of the first diffusion region 120. This trench is formed to penetrate to the n-InP layer 108.

[0109] Next, after removing the resist, impurities are injected to form the first diffusion region 120 and the second diffusion region 122. The subsequent process is the same as the process according to the first embodiment described above.

[0110] In forming the pixel 100 according to the third embodiment, as shown in Figure 27, after forming the n-InP layer 108, an n-InAlAs layer 114 is formed on the upper surface of the n-InP layer 108, and a resist 200 is selectively formed on the upper surface thereof. The n-InAlAs layer 114 may be formed of n-InAlAs as an example, though not limited to this.

[0111] The resist 200 is formed so as to selectively etch the upper surface of the region where the first diffusion region 120 is formed. Then, as shown in Figure 28, a trench is formed based on the resist 200. This trench is formed to penetrate to the n-InAlAs layer 114.

[0112] As shown in Figure 29, after removing the resist, an insulating film 116 is formed on the upper surface, and then a resist 200 is selectively formed. The resist 200 is formed to selectively create trenches in the regions where the first diffusion region 120 and the second diffusion region 122 are formed.

[0113] As shown in Figure 30, trenches are formed using the resist 200 so as to reach the semiconductor layer. Specifically, in the area where the first diffusion region 120 is formed, etching is performed to reach the n-InP layer 108, and in the area where the second diffusion region 122 is formed, etching is performed to reach the n-InAlAs layer 114.

[0114] Subsequently, by removing the resist and injecting impurities, the first diffusion region 120 and the second diffusion region 122 are formed, as shown in Figure 31. The subsequent process is substantially the same as in the first embodiment.

[0115] As described above, according to the embodiments of this disclosure, it is possible to form a structure that suppresses crosstalk to or from adjacent pixels without providing a film to isolate pixels in the photoelectric conversion region. Furthermore, according to some embodiments, it is possible to collect carriers to be collected at the pixels with greater precision while suppressing crosstalk.

[0116] According to the second and third embodiments, it is possible to suppress the difference in carrier recovery efficiency between pixels due to variations in the depth of the first diffusion region 120, which is the main photodiode, by using the second diffusion region 122, which is a sub-photodiode, thereby also suppressing variations in carrier recovery efficiency between pixels.

[0117] <5. Application Examples>

[0118] The technology disclosed herein can be applied to a variety of products. For example, the technology disclosed herein may be implemented as a device mounted on any type of mobile vehicle, such as automobiles, electric vehicles, hybrid electric vehicles, motorcycles, bicycles, personal mobility devices, airplanes, drones, ships, robots, construction machinery, or agricultural machinery (tractors).

[0119] Figure 32 is a block diagram showing a schematic configuration example of a vehicle control system 7000, which is an example of a mobile control system to which the technology described herein may be applied. The vehicle control system 7000 comprises a plurality of electronic control units connected via a communication network 7010. In the example shown in Figure 32, the vehicle control system 7000 comprises a drive system control unit 7100, a body system control unit 7200, a battery control unit 7300, an external information detection unit 7400, an internal information detection unit 7500, and an integrated control unit 7600. The communication network 7010 connecting these plurality of control units may be an in-vehicle communication network compliant with any standard such as CAN (Controller Area Network), LIN (Local Interconnect Network), LAN (Local Area Network), or FlexRay (registered trademark).

[0120] Each control unit comprises a microcomputer that performs calculations according to various programs, a storage unit that stores programs executed by the microcomputer or parameters used in various calculations, and a drive circuit that drives various controlled devices. Each control unit is equipped with a network interface for communication with other control units via the communication network 7010, and a communication interface for communication with devices or sensors inside or outside the vehicle via wired or wireless communication. Figure 32 illustrates the functional configuration of the integrated control unit 7600, which includes a microcomputer 7610, a general-purpose communication interface 7620, a dedicated communication interface 7630, a positioning unit 7640, a beacon receiver 7650, an in-vehicle equipment interface 7660, an audio / image output unit 7670, an in-vehicle network interface 7680, and a storage unit 7690. Other control units similarly include a microcomputer, a communication interface, and a storage unit.

[0121] The drivetrain control unit 7100 controls the operation of devices related to the vehicle's drivetrain according to various programs. For example, the drivetrain control unit 7100 functions as a control device for generating driving force for the vehicle, such as an internal combustion engine or drive motor; a driving force transmission mechanism for transmitting driving force to the wheels; a steering mechanism for adjusting the steering angle of the vehicle; and a braking device for generating braking force for the vehicle. The drivetrain control unit 7100 may also function as a control device such as ABS (Antilock Brake System) or ESC (Electronic Stability Control).

[0122] A vehicle state detection unit 7110 is connected to the drivetrain control unit 7100. The vehicle state detection unit 7110 includes, for example, a gyro sensor for detecting the angular velocity of the vehicle's axial rotational motion, an acceleration sensor for detecting the vehicle's acceleration, or at least one of the sensors for detecting the amount of accelerator pedal operation, brake pedal operation, steering wheel steering angle, engine speed, or wheel rotation speed. The drivetrain control unit 7100 performs calculations using signals input from the vehicle state detection unit 7110 to control the internal combustion engine, drive motor, electric power steering system, brake system, etc.

[0123] The body system control unit 7200 controls the operation of various devices mounted on the vehicle body according to various programs. For example, the body system control unit 7200 functions as a control device for a keyless entry system, a smart key system, a power window system, or various lamps such as headlights, reverse lights, brake lights, turn signals, or fog lights. In this case, the body system control unit 7200 may receive radio waves transmitted from a portable device that replaces a key or signals from various switches. The body system control unit 7200 receives these radio waves or signals and controls the vehicle's door lock system, power window system, lamps, etc.

[0124] The battery control unit 7300 controls the secondary battery 7310, which is the power source for the drive motor, according to various programs. For example, the battery control unit 7300 receives information such as battery temperature, battery output voltage, or remaining battery capacity from the battery device equipped with the secondary battery 7310. The battery control unit 7300 uses these signals to perform calculations and controls the temperature of the secondary battery 7310 or the cooling device provided in the battery device.

[0125] The external information detection unit 7400 detects information from outside the vehicle equipped with the vehicle control system 7000. For example, the external information detection unit 7400 is connected to at least one of the imaging unit 7410 and the external information detection unit 7420. The imaging unit 7410 includes at least one of the following: a Time of Flight (ToF) camera, a stereo camera, a monocular camera, an infrared camera, and other cameras. The external information detection unit 7420 includes at least one of the following: an environmental sensor for detecting the current weather or climate, or an ambient information detection sensor for detecting other vehicles, obstacles, or pedestrians around the vehicle equipped with the vehicle control system 7000.

[0126] The environmental sensor may be at least one of the following: a raindrop sensor for detecting rain, a fog sensor for detecting fog, a sunshine sensor for detecting the degree of sunlight, and a snow sensor for detecting snowfall. The ambient information detection sensor may be at least one of the following: an ultrasonic sensor, a radar device, and a LIDAR (Light Detection and Ranging, Laser Imaging Detection and Ranging) device. These imaging unit 7410 and external information detection unit 7420 may be provided as independent sensors or devices, or as a device in which multiple sensors or devices are integrated.

[0127] Here, Figure 33 shows an example of the installation location of the imaging unit 7410 and the external information detection unit 7420. The imaging units 7910, 7912, 7914, 7916, and 7918 are installed, for example, at least one of the following locations on the vehicle 7900: the front nose, side mirrors, rear bumper, tailgate, and the upper part of the windshield inside the passenger compartment. The imaging unit 7910 installed on the front nose and the imaging unit 7918 installed on the upper part of the windshield inside the passenger compartment mainly acquire images of the front of the vehicle 7900. The imaging units 7912 and 7914 installed on the side mirrors mainly acquire images of the sides of the vehicle 7900. The imaging unit 7916 installed on the rear bumper or tailgate mainly acquires images of the rear of the vehicle 7900. The imaging unit 7918, located at the top of the windshield inside the vehicle, is primarily used for detecting preceding vehicles, pedestrians, obstacles, traffic lights, traffic signs, or lanes.

[0128] Figure 33 shows an example of the imaging range of each imaging unit 7910, 7912, 7914, and 7916. Imaging range a shows the imaging range of imaging unit 7910 located on the front nose, imaging ranges b and c show the imaging ranges of imaging units 7912 and 7914 located on the side mirrors, respectively, and imaging range d shows the imaging range of imaging unit 7916 located on the rear bumper or back door. For example, by superimposing the image data captured by imaging units 7910, 7912, 7914, and 7916, an overhead view image of vehicle 7900 can be obtained.

[0129] The external information detection units 7920, 7922, 7924, 7926, 7928, and 7930, which are installed on the front, rear, sides, corners, and the upper part of the windshield inside the vehicle 7900, may be, for example, ultrasonic sensors or radar devices. The external information detection units 7920, 7926, and 7930, which are installed on the front nose, rear bumper, back door, and the upper part of the windshield inside the vehicle 7900, may be, for example, LIDAR devices. These external information detection units 7920 to 7930 are mainly used for detecting preceding vehicles, pedestrians, or obstacles.

[0130] Returning to Figure 32, the explanation continues. The external information detection unit 7400 causes the imaging unit 7410 to capture images of the area outside the vehicle and receives the captured image data. The external information detection unit 7400 also receives detection information from the connected external information detection unit 7420. If the external information detection unit 7420 is an ultrasonic sensor, radar device, or LIDAR device, the external information detection unit 7400 emits ultrasonic waves or electromagnetic waves and receives information on the received reflected waves. Based on the received information, the external information detection unit 7400 may perform object detection processing such as detecting people, vehicles, obstacles, signs, or characters on the road surface, or distance detection processing. Based on the received information, the external information detection unit 7400 may perform environmental recognition processing to recognize rainfall, fog, or road surface conditions. Based on the received information, the external information detection unit 7400 may calculate the distance to an object outside the vehicle.

[0131] Furthermore, the external information detection unit 7400 may perform image recognition processing or distance detection processing to recognize people, vehicles, obstacles, signs, or characters on the road surface based on the received image data. The external information detection unit 7400 may perform distortion correction or alignment processing on the received image data, and may also synthesize image data captured by different imaging units 7410 to generate an overhead view image or a panoramic image. The external information detection unit 7400 may also perform viewpoint transformation processing using image data captured by different imaging units 7410.

[0132] The in-vehicle information detection unit 7500 detects information inside the vehicle. The in-vehicle information detection unit 7500 is connected to, for example, a driver status detection unit 7510 that detects the driver's state. The driver status detection unit 7510 may include a camera that images the driver, a biosensor that detects the driver's biometric information, or a microphone that collects sounds inside the vehicle. The biosensor is installed, for example, on the seat or steering wheel and detects the biometric information of a passenger sitting in the seat or a driver holding the steering wheel. Based on the detection information input from the driver status detection unit 7510, the in-vehicle information detection unit 7500 may calculate the driver's level of fatigue or concentration, or determine whether the driver is dozing off. The in-vehicle information detection unit 7500 may perform processing such as noise cancellation on the collected audio signals.

[0133] The integrated control unit 7600 controls the overall operation of the vehicle control system 7000 according to various programs. An input unit 7800 is connected to the integrated control unit 7600. The input unit 7800 is implemented by a device that can be operated by the occupant, such as a touch panel, buttons, a microphone, a switch, or a lever. The integrated control unit 7600 may also receive data obtained by voice recognition of audio input via the microphone. The input unit 7800 may be, for example, a remote control device using infrared or other radio waves, or an external device such as a mobile phone or PDA (Personal Digital Assistant) that supports the operation of the vehicle control system 7000. The input unit 7800 may also be, for example, a camera, in which case the occupant can input information through gestures. Alternatively, data obtained by detecting the movement of a wearable device worn by the occupant may be input. Furthermore, the input unit 7800 may include, for example, an input control circuit that generates an input signal based on information input by a passenger or the like using the input unit 7800 and outputs it to the integrated control unit 7600. By operating this input unit 7800, passengers or the like can input various data to the vehicle control system 7000 or instruct it to perform processing operations.

[0134] The memory unit 7690 may include a ROM (Read Only Memory) for storing various programs executed by a microcomputer, and a RAM (Random Access Memory) for storing various parameters, calculation results, or sensor values. The memory unit 7690 may also be implemented using magnetic storage devices such as an HDD (Hard Disk Drive), semiconductor storage devices, optical storage devices, or magneto-optical storage devices.

[0135] The general-purpose communication interface 7620 is a general-purpose communication interface that mediates communication between various devices present in the external environment 7750. The general-purpose communication interface 7620 may implement cellular communication protocols such as GSM (Global System of Mobile communications), WiMAX (registered trademark), LTE (Registered trademark) (Long Term Evolution), or LTE-A (LTE-Advanced), or other wireless communication protocols such as wireless LAN (also known as Wi-Fi (registered trademark)) or Bluetooth (registered trademark). The general-purpose communication interface 7620 may connect, for example, to devices (e.g., application servers or control servers) located on an external network (e.g., the Internet, a cloud network, or a carrier-specific network) via a base station or access point. Furthermore, the general-purpose communication interface 7620 may connect to terminals located near the vehicle (for example, terminals belonging to the driver, pedestrians, or shops, or MTC (Machine Type Communication) terminals) using, for example, P2P (Peer To Peer) technology.

[0136] The Dedicated Communication Interface 7630 is a communication interface that supports communication protocols developed for use in vehicles. The Dedicated Communication Interface 7630 may implement standard protocols such as WAVE (Wireless Access in Vehicle Environment), DSRC (Dedicated Short Range Communications), or cellular communication protocols, which are combinations of lower-layer IEEE 802.11p and upper-layer IEEE 1609. The Dedicated Communication Interface 7630 typically performs V2X communication, a concept that includes one or more of the following: vehicle-to-vehicle communication, vehicle-to-infrastructure communication, vehicle-to-home communication, and vehicle-to-pedestrian communication.

[0137] The positioning unit 7640 performs positioning by receiving GNSS signals from GNSS (Global Navigation Satellite System) satellites (for example, GPS signals from GPS (Global Positioning System) satellites) and generates location information including the vehicle's latitude, longitude, and altitude. The positioning unit 7640 may also determine its current location by exchanging signals with a wireless access point, or it may acquire location information from a terminal such as a mobile phone, PHS, or smartphone that has positioning capabilities.

[0138] The beacon receiver 7650 receives radio waves or electromagnetic waves transmitted from, for example, a radio station installed on a road, and obtains information such as the current location, traffic congestion, road closures, or travel time. The functions of the beacon receiver 7650 may also be included in the dedicated communication interface 7630 described above.

[0139] The in-vehicle equipment interface 7660 is a communication interface that mediates connections between the microcomputer 7610 and various in-vehicle equipment 7760 located inside the vehicle. The in-vehicle equipment interface 7660 may establish a wireless connection using wireless communication protocols such as Wi-Fi, Bluetooth (registered trademark), NFC (Near Field Communication), or WUSB (Wireless USB). Furthermore, the in-vehicle equipment interface 7660 may establish wired connections such as USB (Universal Serial Bus), HDMI (Registered Trademark) (High-Definition Multimedia Interface), or MHL (Mobile High-Definition Link) via connection terminals (and cables if necessary) not shown. The in-vehicle equipment 7760 may include, for example, at least one of the following: a mobile device or wearable device owned by a passenger, or an information device brought into or installed in the vehicle. The in-vehicle equipment 7760 may also include a navigation device that performs route searching to any destination. The in-vehicle equipment interface 7660 exchanges control signals or data signals with these in-vehicle equipment 7760s.

[0140] The in-vehicle network interface 7680 is an interface that mediates communication between the microcomputer 7610 and the communication network 7010. The in-vehicle network interface 7680 transmits and receives signals and other data in accordance with a predetermined protocol supported by the communication network 7010.

[0141] The microcomputer 7610 of the integrated control unit 7600 controls the vehicle control system 7000 according to various programs based on information acquired via at least one of the following: general-purpose communication I / F 7620, dedicated communication I / F 7630, positioning unit 7640, beacon receiver 7650, in-vehicle equipment I / F 7660, and in-vehicle network I / F 7680. For example, the microcomputer 7610 may calculate control target values ​​for the drive force generator, steering mechanism, or braking device based on acquired in-vehicle and external information, and output control commands to the drivetrain control unit 7100. For example, the microcomputer 7610 may perform coordinated control aimed at realizing ADAS (Advanced Driver Assistance System) functions, including collision avoidance or impact mitigation, following based on distance between vehicles, maintaining vehicle speed, collision warning, or lane departure warning. Furthermore, the microcomputer 7610 may perform cooperative control for purposes such as autonomous driving, where the vehicle drives autonomously without driver intervention, by controlling the drive force generating device, steering mechanism, or braking device, etc., based on the acquired information about the vehicle's surroundings.

[0142] The microcomputer 7610 may generate three-dimensional distance information between the vehicle and surrounding structures, people, and other objects based on information acquired via at least one of the general-purpose communication I / F 7620, dedicated communication I / F 7630, positioning unit 7640, beacon receiver 7650, in-vehicle equipment I / F 7660, and in-vehicle network I / F 7680, and create local map information including surrounding information of the vehicle's current location. Furthermore, the microcomputer 7610 may predict dangers such as vehicle collision, proximity of pedestrians, or entry into a closed road based on the acquired information, and generate warning signals. These warning signals may, for example, be signals to generate a warning sound or illuminate a warning lamp.

[0143] The audio-image output unit 7670 transmits at least one of audio and image output signals to an output device capable of visually or audibly notifying information to the vehicle's occupants or to those outside the vehicle. In the example in Figure 32, the output devices are exemplified as an audio speaker 7710, a display unit 7720, and an instrument panel 7730. The display unit 7720 may include, for example, at least one of an onboard display and a head-up display. The display unit 7720 may also have an AR (Augmented Reality) display function. The output devices may also be other devices other than these, such as headphones, wearable devices such as glasses-type displays worn by occupants, projectors, or lamps. If the output device is a display device, the display device visually displays the results obtained from various processes performed by the microcomputer 7610 or information received from other control units in various formats such as text, images, tables, graphs, etc. Furthermore, if the output device is an audio output device, the audio output device converts the audio signal, consisting of the reproduced audio data or sound data, into an analog signal and outputs it audibly.

[0144] In the example shown in Figure 32, at least two control units connected via the communication network 7010 may be integrated into a single control unit. Alternatively, individual control units may be composed of multiple control units. Furthermore, the vehicle control system 7000 may include other control units not shown. Also, in the above description, some or all of the functions performed by one control unit may be assigned to other control units. In other words, as long as information is transmitted and received via the communication network 7010, predetermined calculation processing may be performed by any of the control units. Similarly, a sensor or device connected to one control unit may be connected to another control unit, and multiple control units may transmit and receive detection information to and from each other via the communication network 7010.

[0145] Furthermore, the circuits for realizing each function of the solid-state imaging device 1 according to this embodiment, as described using Figures 1 to 31, can be implemented in any control unit or the like. In the vehicle control system 7000 described above, the solid-state imaging device 1 according to this embodiment, as described using Figures 1 to 31, can be applied to a part of the imaging unit 7410, the external information detection unit 7420, or the driver state detection unit 7510 of the application example shown in Figure 32.

[0146] The embodiments described above may also take the following forms.

[0147] (1) A solid-state imaging device comprising: a pixel having a photoelectric conversion layer that receives incident light and converts it into carriers based on the received light intensity; and a first diffusion region that acquires the carriers converted in light by the photoelectric conversion layer, wherein the pixel further has a second diffusion region between it and an adjacent pixel, located closer to the first diffusion region of the adjacent pixel than to the first diffusion region of the adjacent pixel, and acquiring the carriers converted in the photoelectric conversion layer, and the first diffusion region is formed to a deeper position in the photoelectric conversion layer than the second diffusion region.

[0148] (2) The solid-state imaging apparatus according to (1), wherein the photoelectric conversion layer is a layer formed by including n-type InGaAs.

[0149] (3) The solid-state imaging apparatus according to (2), wherein the first diffusion region and the second diffusion region are layers in which p-type impurities are diffused into the photoelectric conversion layer and the n-type InP layer.

[0150] (4) The solid-state imaging apparatus according to (2) or (3), wherein the first electrode that propagates carriers from the first diffusion region is formed in contact with the photoelectric conversion layer.

[0151] (5) The solid-state imaging apparatus according to (4), wherein the second diffusion region is further formed in a layer of another compound formed on the opposite side of the InP layer from the photoelectric conversion layer, and a second electrode for propagating carriers from the second diffusion region is formed in contact with the layer of the other material.

[0152] (6) The solid-state imaging apparatus according to any one of (1) to (5), wherein the second diffusion region is arranged in separate groups for each pixel.

[0153] (7) The solid-state imaging apparatus according to any one of (1) to (6), wherein the second diffusion region is arranged to surround the first diffusion region for each pixel.

[0154] (8) The solid-state imaging apparatus according to any one of (1) to (7), wherein the pixels are transferred to a floating diffusion layer that shares carriers output from the first diffusion region and the second diffusion region, and a signal value based on the light reception intensity is acquired in a subsequent circuit.

[0155] (9) The solid-state imaging apparatus according to (8), which shares a transfer gate for transferring carriers output from the first diffusion region and the second diffusion region to the floating diffusion layer.

[0156] (10) The solid-state imaging apparatus according to (8), wherein the transfer gate for transferring carriers output from the first diffusion region to the floating diffusion layer and the transfer gate for transferring carriers output from the second diffusion region to the floating diffusion layer are separate.

[0157] (11) The solid-state imaging apparatus according to any one of (1) to (7), wherein the pixel transfers carriers output from the first diffusion region and the second diffusion region to separate floating diffusion layers, and a subsequent circuit adds the signal values ​​obtained from each diffusion layer to obtain a signal value based on the received light intensity.

[0158] (12) The solid-state imaging apparatus according to (1), wherein the photoelectric conversion layer is a layer formed by comprising at least one of n-type InGaAsP, InAlAs, GaAsSb, or InGaAsSb.

[0159] (13) Electronic device comprising: a pixel having a photoelectric conversion layer that receives incident light and converts it into carriers based on the received light intensity; a first diffusion region that acquires the carriers converted in light by the photoelectric conversion layer, wherein the pixel further has a second diffusion region between itself and an adjacent pixel, located closer to the first diffusion region of the pixel than to the first diffusion region of the adjacent pixel, for acquiring the carriers converted in the photoelectric conversion layer; and a signal processing circuit that processes a signal output from the pixel.

[0160] The aspects of this disclosure are not limited to the embodiments described above, but include various conceivable variations, and the effects of this disclosure are not limited to those described above. The components in each embodiment may be appropriately combined and applied. That is, various additions, modifications, and partial deletions are possible, as long as they do not deviate from the conceptual idea and spirit of this disclosure derived from the claims and their equivalents.

[0161] 1: Solid-state imaging device, 10: Pixel array, 100: Pixel, 102: Transparent electrode, 104: n+INP layer, 106: Photoelectric conversion layer, 108: n-INP layer, 110: Wiring layer, 112: Substrate, 114: n-InAlAs layer, 116: Insulating film, 118: Insulating film, 120: First diffusion region, 122: Second diffusion region, 140: First electrode, 142: Second electrode, 150: Connecting wiring, 160: Wiring, L1: First photodetector, L2: Second photodetector, C1: Capacitor, C2: Capacitor, Cfd: Capacitor, TRG: Transfer gate, TRG1: Transfer gate, TRG2: Transfer gate, RST: Reset transistor, FD: Floating diffusion region, FD1: Floating diffusion region, FD2: Floating diffusion region, AMP: Amplifier transistor, SEL: Selector transistor, VSL: Signal line, 200: Resist, 202: Metal film, 12: Control circuit, 14: First scanning circuit, 144: Signal line, 16: Second scanning circuit, 162: Signal line, 18: Signal processing circuit, 180: Signal line,

Claims

1. A solid-state imaging device comprising: a pixel having a photoelectric conversion layer that receives incident light and converts it into carriers based on the received light intensity; and a first diffusion region that acquires the carriers converted in light by the photoelectric conversion layer, wherein the pixel further has a second diffusion region between it and an adjacent pixel, located closer to the first diffusion region of the adjacent pixel than to the first diffusion region of the adjacent pixel, and acquiring the carriers converted in the photoelectric conversion layer, and the first diffusion region is formed to a deeper position in the photoelectric conversion layer than the second diffusion region.

2. The solid-state imaging apparatus according to claim 1, wherein the photoelectric conversion layer is a layer formed containing n-type InGaAs.

3. The solid-state imaging apparatus according to claim 2, wherein the first diffusion region and the second diffusion region are layers in which p-type impurities are diffused into the photoelectric conversion layer and the n-type InP layer.

4. The solid-state imaging apparatus according to claim 3, wherein the first electrode that propagates carriers from the first diffusion region is formed in contact with the photoelectric conversion layer.

5. The solid-state imaging apparatus according to claim 4, wherein the second diffusion region is further formed in a layer of another compound formed on the opposite side of the InP layer from the photoelectric conversion layer, and the second electrode for propagating carriers from the second diffusion region is formed in contact with the layer of the other material.

6. The solid-state imaging apparatus according to claim 1, wherein the second diffusion region is arranged in separate groups for each pixel.

7. The solid-state imaging apparatus according to claim 1, wherein the second diffusion region is arranged to surround the first diffusion region for each pixel.

8. The solid-state imaging apparatus according to claim 1, wherein the pixels are transferred to a floating diffusion layer that shares carriers output from the first diffusion region and the second diffusion region, and a signal value based on the light reception intensity is acquired in a subsequent circuit.

9. The solid-state imaging apparatus according to claim 8, which shares a transfer gate for transferring carriers output from the first diffusion region and the second diffusion region to the floating diffusion layer.

10. The solid-state imaging apparatus according to claim 8, wherein the transfer gate for transferring carriers output from the first diffusion region to the floating diffusion layer and the transfer gate for transferring carriers output from the second diffusion region to the floating diffusion layer are separate.

11. The solid-state imaging apparatus according to claim 1, wherein the pixel transfers carriers output from the first diffusion region and the second diffusion region to separate floating diffusion layers, and a subsequent circuit adds the signal values ​​obtained from each diffusion layer to obtain a signal value based on the received light intensity.

12. The solid-state imaging apparatus according to claim 1, wherein the photoelectric conversion layer is a layer formed comprising at least one of n-type InGaAsP, InAlAs, GaAsSb, or InGaAsSb.

13. An electronic device comprising: a pixel having a photoelectric conversion layer that receives incident light and converts it into carriers based on the received light intensity; a first diffusion region that acquires the carriers converted in light by the photoelectric conversion layer, wherein the pixel further has a second diffusion region between it and an adjacent pixel, located closer to the first diffusion region of the pixel than to the first diffusion region of the adjacent pixel, for acquiring the carriers converted in the photoelectric conversion layer; and a signal processing circuit that processes the signal output from the pixel.

Images