Imaging device and electronic apparatus

Abstract

The present technology relates to an imaging device and an electronic apparatus that enable simplification of a configuration for applying a negative bias to a pixel. The imaging device comprises: a semiconductor substrate in which a photoelectric conversion unit is provided for each pixel; a first electrode provided in a trench separating the pixels from each other in the semiconductor substrate; a second electrode provided on a light incident surface side of the semiconductor substrate; and a pad to which a terminal for applying a voltage is connected. The second electrode is connected to the first electrode and provided to extend to the pad. The present technology can be applied to, for example, an imaging device that enhances pinning and improves dark characteristics by applying a negative bias to a pixel.

Description

Imaging Device, Electronic Device

[0001] The present technology relates to an imaging device and an electronic device, and more particularly, to an imaging device and an electronic device that can improve imaging characteristics.

[0002] Conventionally, in an imaging device such as a CMOS (Complementary Metal Oxide Semiconductor) image sensor, for example, a configuration in which an electrode is embedded in a trench for separating pixels and a negative bias is applied has been proposed (see, for example, Patent Document 1).

[0003] Japanese Patent Application Laid-Open No. 2023-027760

[0004] There is a demand for providing an imaging device with a simplified configuration for applying a negative bias to an electrode in a trench and high reliability.

[0005] The present technology has been made in view of such a situation, and simplifies the configuration for applying a negative bias to an electrode in a trench and improves the reliability.

[0006] An imaging device according to one aspect of the present technology includes a semiconductor substrate provided with a photoelectric conversion unit for each pixel, a first electrode provided in a trench for separating the pixels in the semiconductor substrate, a second electrode provided on the light incident surface side of the semiconductor substrate, and a pad to which a terminal for applying a voltage is connected. The second electrode is connected to the first electrode and extends to the pad.

[0007] An electronic device according to one aspect of the present technology includes a semiconductor substrate provided with a photoelectric conversion unit for each pixel, a first electrode provided in a trench for separating the pixels in the semiconductor substrate, a second electrode provided on the light incident surface side of the semiconductor substrate, and a pad to which a terminal for applying a voltage is connected. The second electrode is connected to the first electrode and extends to the pad, and an electronic device including a processing unit that processes a signal from the imaging device.

[0008] In one aspect of this technology, the imaging device includes a semiconductor substrate on which a photoelectric conversion unit is provided for each pixel, a first electrode provided in a trench separating the pixels in the semiconductor substrate, a second electrode provided on the light incident surface side of the semiconductor substrate, and a pad to which a terminal for applying voltage is connected, wherein the second electrode is connected to the first electrode and extends to the pad.

[0009] One aspect of this technology involves an electronic device that includes the aforementioned imaging device.

[0010] Furthermore, the imaging device and electronic equipment may be independent devices or internal blocks that constitute a single device.

[0011] This is a diagram showing an example of the configuration of an imaging device. This is a diagram showing an example of the configuration of the pixel array section. This is a diagram showing the configuration of one embodiment of an imaging device to which this technology is applied. This is a diagram for explaining image height. This is a diagram for explaining pupil correction. This is a diagram for explaining the stacked structure of the part related to electrodes. This is a diagram showing an example of the planar configuration of an imaging device. This is a diagram showing an example of the planar configuration of an imaging device. This is a diagram showing another example of the configuration of an imaging device. This is a diagram for explaining the manufacturing of an imaging device. This is a diagram for explaining the manufacturing of an imaging device. This is a diagram showing an example of the configuration of a pad. This is a diagram showing an example of the configuration of a pad. This is a diagram showing an example of the configuration of a pad. This is a diagram showing an example of the configuration of a pad. This is a diagram showing an example of the configuration of a pad. This is a diagram showing an example of the configuration of a pad. This is a diagram showing an example of the configuration of a pad. This is a diagram showing an example of the configuration of an electronic device. This is a diagram showing an example of the schematic configuration of an endoscopic surgical system. This is a block diagram showing an example of the functional configuration of a camera head and a CCU. This is a block diagram showing an example of the schematic configuration of a vehicle control system. This is an explanatory diagram showing an example of the installation position of the external information detection unit and the imaging unit.

[0012] The following describes the embodiments for implementing this technology.

[0013] <Example of schematic configuration of imaging device> Figure 1 shows a schematic configuration of an imaging device including an image sensor according to this disclosure.

[0014] The imaging device 1 shown in Figure 1 is configured to have a pixel array section 3 in which pixels 2 are arranged in a two-dimensional array on a semiconductor substrate 12 using silicon (Si) as the semiconductor, and a peripheral circuit section around it. The peripheral circuit section includes a vertical drive circuit 4, a column signal processing circuit 5, a horizontal drive circuit 6, an output circuit 7, a control circuit 8, and the like.

[0015] Pixel 2 is configured to have a photodiode as a photoelectric conversion element and multiple pixel transistors. The multiple pixel transistors consist of four MOS transistors, for example, a transfer transistor, a selection transistor, a reset transistor, and an amplification transistor.

[0016] Pixel 2 can also be a shared pixel structure. This shared pixel structure consists of multiple photodiodes, multiple transfer transistors, one shared floating diffusion region, and one shared other pixel transistor. In other words, in a shared pixel, the photodiodes and transfer transistors that make up multiple unit pixels share one other pixel transistor.

[0017] The control circuit 8 receives the input clock and data that commands the operating mode, and outputs data such as internal information of the imaging device 1. Specifically, the control circuit 8 generates clock signals and control signals that serve as the reference for the operation of the vertical drive circuit 4, column signal processing circuit 5, and horizontal drive circuit 6, etc., based on the vertical synchronization signal, horizontal synchronization signal, and master clock. The control circuit 8 then outputs the generated clock signals and control signals to the vertical drive circuit 4, column signal processing circuit 5, and horizontal drive circuit 6, etc.

[0018] The vertical drive circuit 4 is composed of, for example, a shift register, and selects a pixel drive wiring 10, supplies pulses to the selected pixel drive wiring 10 to drive the pixel 2, and drives the pixel 2 row by row. That is, the vertical drive circuit 4 sequentially selects and scans each pixel 2 of the pixel array 3 row by row in the vertical direction, and supplies a pixel signal based on the signal charge generated in the photoelectric conversion unit of each pixel 2 according to the amount of light received to the column signal processing circuit 5 through the vertical signal line 9.

[0019] The column signal processing circuit 5 is located for each column of pixels 2 and performs signal processing, such as noise reduction, on the signals output from each row of pixels 2 for each pixel column. For example, the column signal processing circuit 5 performs signal processing such as CDS (Correlated Double Sampling) and AD conversion to remove pixel-specific fixed pattern noise.

[0020] The horizontal drive circuit 6 is composed of, for example, a shift register, and sequentially outputs horizontal scanning pulses to select each of the column signal processing circuits 5 in order, causing each of the column signal processing circuits 5 to output a pixel signal to the horizontal signal line 11.

[0021] The output circuit 7 processes the signals sequentially supplied from each of the column signal processing circuits 5 through the horizontal signal line 11 and outputs them. The output circuit 7 may, for example, only perform buffering, or it may perform black level adjustment, column variation correction, various digital signal processing, etc. The input / output terminal 13 exchanges signals with the outside.

[0022] The imaging device 1 configured as described above is a CMOS image sensor called a column AD type, in which a column signal processing circuit 5 that performs CDS processing and AD conversion processing is arranged for each pixel row.

[0023] Furthermore, the imaging device 1 is a back-illuminated MOS type imaging device in which light is incident from the back side opposite to the front side of the semiconductor substrate 12 on which the pixel transistors are formed.

[0024] <Example of the configuration of the pixel array section 3> Figure 2 is a diagram showing an example of the configuration of the pixel array section 3 of the imaging device 1.

[0025] The pixel array section 3 shown in Figure 2 includes an effective pixel area 31 where effective pixels are arranged and a light-shielding pixel area 32 where OPB (optical black) pixels are arranged. The light-shielding pixel area 32, located at the top of the pixel array section 3 in the figure, is a light-shielding area that is shielded from incoming light. The effective pixel area 31 is an open area that is not shielded from light.

[0026] The effective pixel region 31, located within the aperture region, contains effective pixels (hereinafter referred to as effective pixels 31 as appropriate) from which pixel signals are read out when generating an image.

[0027] The light-shielding pixel area 32, located within the upper light-shielding area, contains light-shielding pixels (hereinafter referred to as light-shielding pixels 32 as appropriate) used for reading out the black level signal, which is a pixel signal indicating the black level of the image.

[0028] Although not shown in the diagram, the configuration can also include an effective-non-effective pixel region where effective-non-effective pixels are located, situated between the effective pixel region 31 and the light-shielding pixel region 32. The effective-non-effective pixel region is an area where effective-non-effective pixels are located, whose readout pixel signals are not used in image generation. These effective-non-effective pixels primarily serve to ensure uniformity of the characteristics of the pixel signals of the effective pixels 31.

[0029] A pad region 33 is provided on the upper side of the light-shielding pixel region 32 in the figure. Figure 2 shows an example in which five pad regions 33 are formed. Each pad region 33 has an opening formed to expose the bonding pad.

[0030] The imaging device 1 has a structure in which a photoelectric conversion layer, a silicon substrate, and a wiring layer are stacked. On the silicon substrate, a through-electrode portion is formed that connects a photoelectric conversion element that receives incident light and converts it into a signal charge, and a signal charge holding portion that holds the signal charge. On the silicon substrate, a first guard ring 35 is arranged along the outer circumference of the imaging device 1 (outer circumference of the chip), and a second guard ring 34 is arranged along the periphery of each pad region 33, respectively, as a guard ring to prevent chipping.

[0031] Chipping refers to the process of processing silicon (Si) in steps such as dry etching and dicing, where silicon debris or other damage can cause scratches on the silicon (Si). To prevent the propagation of these scratches, guard rings such as the first guard ring 35 and the second guard ring 34 are placed.

[0032] The present invention can be applied to arrangements other than those shown in Figure 2 for the pixel array 3. For example, although the example shown illustrates the light-shielding pixel region 32 being formed on one side of the effective pixel 31, it can also be configured to be provided on two to four sides. Similarly, although the example shown illustrates the pad region 33 being formed on one side of the effective pixel 31, it can also be configured to be provided on two to four sides. Furthermore, the imaging device 1 can be composed of the effective pixel region 31 and the pad region 33 without providing the light-shielding pixel region 32.

[0033] <Example of Cross-Sectional Configuration of Imaging Device> Figure 3 is a diagram showing an example of the cross-sectional configuration of the imaging device 1. The left diagram of Figure 3 shows an example of the cross-sectional configuration of effective pixels 31 arranged in a matrix in the effective pixel region 31, the middle diagram shows an example of the cross-sectional configuration of light-shielding pixels 32 arranged in a matrix in the light-shielding pixel region 32, and the right diagram shows an example of the cross-sectional configuration of the pad 101 formed in the pad region 33.

[0034] The effective pixels 31 described below will be explained using the back-illuminated type as an example, but this technology can also be applied to front-illuminated types.

[0035] The effective pixels 31 shown in Figure 3 have photodiodes (PDs) 71, which are photoelectric conversion elements of each pixel, formed inside the Si substrate 70 (corresponding to the semiconductor substrate 12 in Figure 1). An oxide film 72 is formed on the light incident side of the PD 71 (the upper side in the figure, which is the back side). The oxide film 72 is formed of, for example, SiO2 (silicon dioxide). A transparent electrode 73 is formed on the oxide film 72. The transparent electrode 73 is made of a transparent material and functions as an electrode. For example, transparent electrode materials such as ITO (indium tin oxide), IZO (indium zinc oxide), and ZnO (zinc oxide) are used to construct the electrode.

[0036] A light-shielding wall 74 is formed on the transparent electrode 73. The light-shielding wall 74 is provided to prevent light leakage to adjacent pixels and is formed between adjacent PDs 71. The light-shielding wall 74 is formed using a metallic material such as W (tungsten). The effective pixels 31 shown in Figure 3 represent pixels located at the edge of the screen within the pixel array 3, and show the case where pupil correction is applied.

[0037] The light-shielding wall 74 is formed within the color filter 75. The color filter 75 is formed on the transparent electrode 73. An OCL (on-chip lens) 76 is formed on the upper side of the color filter 75, on the back side of the Si substrate 70, to focus the incident light onto the PD 71. Although not shown in Figure 3, a configuration in which a cover glass or a transparent plate such as resin is bonded to the OCL 76 is also possible.

[0038] Now, let's explain pupil correction with reference to Figures 4 and 5. Figure 4 is a plan view of a pixel array 3 having multiple pixels, viewed from a direction perpendicular to the light-receiving surface of the pixel array 3 (hereinafter also referred to as the optical axis direction).

[0039] In Figure 4, position P1 in the pixel array section 51 is the central position on the light-receiving surface of the pixel array section 51, i.e., the position of the image height center. Position P2, located to the left of position P1 in the figure, is a position on the image height edge side (high image height side) away from the image height center, i.e., a position on the edge side of the light-receiving surface of the pixel array section 3.

[0040] Figure 5 shows the structure of the effective pixels 31 considering pupil correction. The right side of Figure 5 shows the structure of the effective pixels 31 at the center of the field of view, and the left side of Figure 5 shows the structure of the effective pixels 31 at the edge of the field of view.

[0041] Since light enters the on-chip lens 76 at various angles relative to the imaging surface, if the effective pixels 31 at the center of the field of view and the effective pixels 31 at the edges of the field of view have the same structure, light cannot be collected efficiently, resulting in a difference in sensitivity between the effective pixels 31 at the center of the field of view and the effective pixels 31 at the edges of the field of view.

[0042] In order to avoid a sensitivity difference between the effective pixel 31 at the center of the angle of view and the effective pixel 31 at the edge of the angle of view and to achieve a constant sensitivity, for example, at the center of the imaging surface (center of the angle of view), the optical axis of the on-chip lens 76 is aligned with the aperture of the PD 71, and as the edge of the angle of view is approached, there is a technique called pupil correction in which the position of the PD 71 is shifted to align with the direction of the chief ray.

[0043] In the effective pixel 31 arranged at the center of the angle of view, as shown by the arrow in the left diagram of FIG. 5, incident light enters the PD 71 substantially perpendicularly. However, in the effective pixel 31 arranged at the edge of the angle of view, as shown by the arrow in the right diagram of FIG. 5, incident light enters the PD 71 obliquely.

[0044] Pupil correction is applied to the on-chip lens 76 and the color filter 75 so that they can efficiently collect light even for oblique light. The amount of pupil correction increases as the edge of the angle of view is approached from the center of the angle of view (e.g., the center of the pixel portion).

[0045] Referring to the left diagram of FIG. 5, in the effective pixel 31 at the center of the angle of view, for example, incident light enters from the direction of the central axis of the on-chip lens 76. Therefore, the incident light collected by the on-chip lens 76 passes through the color filter 75, is spectrally separated, and enters the PD 71.

[0046] That is, in the effective pixel 31 at the center of the angle of view, the incident light passing through the center of the on-chip lens 76 passes through the center of the color filter 75 and irradiates the center of the PD 71. Therefore, pupil correction is not performed in the effective pixel 31 at the center of the angle of view.

[0047] Referring to the right diagram of FIG. 5, in the effective pixel 31 at the edge of the angle of view, which is outside the center of the angle of view, pupil correction is applied to the on-chip lens 76 and the color filter 75 so that they can efficiently collect light even for oblique light. In the right diagram of FIG. 5, the color filter 75 is arranged at a position shifted by a predetermined amount to the right in the figure with respect to the aperture of the PD 71.

[0048] Furthermore, the on-chip lens 76 is disposed at a position shifted by a predetermined amount in the right direction from the color filter 75. Depending on the amount of shift of the color filter 75, the light-shielding wall 74 disposed between the color filters 75 is also disposed at a position shifted by a predetermined amount in the right direction in the figure. The amount of shift of the color filter 75 and the on-chip lens 76 increases from the center of the angle of view toward the edge of the angle of view.

[0049] Returning to the description with reference to FIG. 3, a wiring layer 77 is formed on the opposite side (the upper side in the figure, which is the surface side) of the light incident side of the PD 71. A plurality of transistors are formed in this wiring layer 77. Although not shown, pixel transistors such as transfer transistors, amplifier transistors, selection transistors, and reset transistors are formed.

[0050] A trench 81 is formed between the active pixels 31. This trench 81 is formed in a shape that penetrates the Si substrate 70 in the depth direction (the vertical direction in the figure, the direction from the surface to the back surface) between adjacent active pixels 31. Here, although the description continues assuming that the trench penetrates the Si substrate 70 and reaches the wiring layer 77 side, a trench that does not penetrate and reaches only halfway may be used.

[0051] A sidewall film 82 made of SiO2 is formed on the inner wall of the trench 81, and a transparent electrode 83 made of a transparent electrode material is embedded inside.

[0052] The trench 81 also functions as a light-shielding wall between pixels so that unnecessary light does not leak to adjacent active pixels 31. The periphery of the trench 81 is the Si substrate 70, and the inside of the trench 81 is composed of the sidewall film 82 and the transparent electrode 83. Since these materials have different refractive indices, by arranging materials with different refractive indices, light can be prevented from leaking into adjacent pixels, the light can be returned into the PD 71, and the amount of light remaining in the PD 71 can be increased.

[0053] The transparent electrodes, formed from a transparent electrode material, have a transparent electrode 73 on the light incident surface side of PD71, and a transparent electrode 83 is located within the trench 81, which is part of the side wall of PD71. The transparent electrodes 73 and 83 are connected and formed from the same material. The transparent electrode 73, which is provided in the lateral direction in the figure, is also provided in the light-shielding pixel region 32 and extends further to the pad region 33. By forming the electrodes from the same material and extending them from the effective pixel region 31 to the pad region 33, the number of manufacturing steps can be reduced, and manufacturing costs can be lowered.

[0054] The light-shielding pixel region 32 is a region located adjacent to the effective pixel region 31 and has a cross-sectional configuration as shown in Figure 3. The basic configuration of the light-shielding pixel 32 can be basically the same as that of the effective pixel 31, except that it is light-shielded. A light-shielding film 91 is formed in the light-shielding pixel region 32 and placed on the light-shielding pixel 32, so that incident light is blocked.

[0055] An oxide film 72 is formed on the upper surface of the PD 71 of the light-shielding pixel 32, and a transparent electrode 73 is formed on the oxide film 72. As described above, this transparent electrode 73 is an extension of the transparent electrode 73 formed in the effective pixel region 31 and is connected to the transparent electrode 73 formed in the effective pixel region 31.

[0056] A trench 81 is formed on the side surrounding the PD 71 located in the light-shielding pixel region 32, and a side wall film 82 and a transparent electrode 83 are formed inside the trench 81. In the light-shielding pixel 32 as well, the transparent electrode 83 in the trench 81 is connected to the transparent electrode 73 formed on the light incident surface side of the light-shielding pixel 32.

[0057] The light-shielding pixel region 32 may be configured without an on-chip lens 76. Figure 3 shows a configuration without an on-chip lens 76, in which an oxide film 92 is formed on the light-shielding film 91. The oxide film 92 may be made of the same material as the on-chip lens 76, or it may have the shape of the on-chip lens 76, that is, a configuration in which an on-chip lens 76 is provided in the light-shielding pixel region 32.

[0058] The transparent electrode 73 formed in the effective pixel region 31 extends to the light-shielding pixel region 32, and further extends to the pad region 33. In the pad region 33, a pad 101 is formed in the open area. The pad 101 is made of, for example, aluminum (AL). An insulating film 103 is provided between the pad 101 and the Si substrate 70.

[0059] The transparent electrode 73, which extends from the effective pixel region 31, and the pad 101 are connected via an electrode 102. The electrode 102 may be made of a transparent electrode material and provided as a transparent electrode, or it may be provided as an electrode made of a non-transparent conductive material.

[0060] The pad 101 is connected to a terminal (not shown), and power is supplied from an external source through that terminal. Alternatively, vias connected to a logic circuit (not shown) are connected to the pad 101, and power controlled by the logic circuit is supplied to the pad 101.

[0061] The power supplied to the pad 101 is supplied to the electrode 102, to the transparent electrode 73 connected to the electrode 102, and to the transparent electrodes 83 in each trench 81 connected to the transparent electrode 73. In this way, the voltage supplied to the pad 101 is supplied to the transparent electrodes 83 provided on the side walls of each effective pixel 31 via the transparent electrode 73 which extends to the effective pixel region 31.

[0062] In the imaging device 1 shown in Figure 3, a voltage of 0V or less (negative bias) can be applied from inside or outside the pixel array 3. By applying a negative bias, the vertical electric field can be strengthened, improving the efficiency of electron extraction from PD71. Furthermore, pinning at the side walls of PD71 can be strengthened, improving the dark characteristics.

[0063] By using the same material for the transparent electrode 83 placed at each pixel, the transparent electrode 73 connected to the transparent electrode 83, and the electrode 102 connected to the transparent electrode 73 and provided for connection to the pad 101, it is possible to reduce contact failures and the effects of differences in resistance values ​​that may occur when different materials are used. Furthermore, by configuring the transparent electrodes in this way, the imaging device 1 can be covered with the transparent electrode material, thereby improving moisture resistance. Thus, the reliability of the imaging device 1 can be improved.

[0064] An insulating film 93 is provided inside the Si substrate 70 between the light-shielding pixel region 32 and the pad region 33. The insulating film 93 is a region embedded only in the trench 81 with an insulator, and is provided to electrically separate the region where PD71 (effective pixels 31, light-shielding pixels 32) is provided from the region where PD71 (pixels) is not provided (pad region 33). The insulating film 93 can be made of the same material as the sidewall film 82, for example, and the insulating film 93 can be a region where only the sidewall film 82 is formed.

[0065] Here, we are using an imaging device 1 equipped with a light-shielding pixel region 32 as an example, but this technology can also be applied to an imaging device 1 that does not have a light-shielding pixel region 32. In an imaging device 1 that does not have a light-shielding pixel region 32, an effective pixel region 31 and a pad region 33 are provided adjacent to each other, and the transparent electrode 73 formed in the effective pixel region 31 extends to the pad 101 of the pad region 33.

[0066] Figure 6 shows an enlarged view of region a, which is the area enclosed by a dotted line within the light-shielding pixel region 32 shown in Figure 3, and is located between the transparent electrode 83 and the insulating film 93 at the edge of the light-shielding pixel region 32. Region a is an area where no light-shielding pixels 32 are located. Region a is located within the light-shielding pixel region 32 (or within the pad region 33), and its basic configuration is the same as that of the light-shielding pixel 32, but differs in that the PD 71 is not provided.

[0067] Here, we will enlarge and explain region a, but the stacked layers, their structure, and materials are the same in the light-shielding pixel region 32, and the structure in region a described below is also the structure of the light-shielding pixel region 32. Furthermore, in the effective pixel region 31, the structure is basically the same as in region a, except that the light-shielding film 91 becomes the light-shielding wall 74 and the color filter 75.

[0068] Region a is configured in which, from top to bottom in the figure, a light-shielding film 91, a barrier metal 111, a transparent electrode 73, an oxide film 72, and a Si substrate 70 are stacked.

[0069] The light-shielding film 91 can be made of, for example, W (tungsten). The barrier metal 111 can be made of, for example, TiN (titanium nitride). The transparent electrode 73 can be made of, for example, ITO, IZO, ZnO, etc. The oxide film 72 can be made of, for example, SiO2. Note that the materials listed here are just examples and not limitations.

[0070] The oxide film 72 is provided with a partially opened opening 121. The transparent electrode 73 and the Si substrate 70 are in contact at this opening 121. For example, during manufacturing, the transparent electrode 73 may become charged, and a discharge may occur between the Si substrate 70 and the transparent electrode 73, or between the barrier metal 111 and the light-shielding film 91, potentially damaging the imaging pixel 1. The opening 121 is provided within region a, which does not have any role in the electrical circuit. In order to connect the transparent electrode 73 and the Si substrate 70 in such a region and create a structure in which a discharge does not occur (or is not affected by a discharge), a region is provided in which the transparent electrode 73 and the Si substrate 70 are in contact.

[0071] Figure 6B shows another example of a configuration in region a. The example of a configuration shown in Figure 6B consists of a light-shielding film 91, a barrier metal 111, an oxide film 112, a transparent electrode 73, an oxide film 72, a dielectric film 113, and a Si substrate 70, stacked in order from top to bottom in the figure.

[0072] Compared to the configuration shown in Figure 6A, the configuration shown in Figure 6B differs in that an oxide film 112 is added between the barrier metal 111 and the transparent electrode 73, and a dielectric film 113 is added between the oxide film 72 and the Si substrate 70; other aspects are the same. By providing the dielectric film 113, the characteristics against pinning and dark current can be improved.

[0073] The configuration of the laminated film shown in Figure 6A or Figure 6B can be basically the same even within the effective pixel region 31.

[0074] <Example of Planar Configuration of Imaging Device> Figure 7 shows an example of the planar configuration of the imaging device 1. In Figure 7, the arrangement of transparent electrodes 73 and 83 will be explained as an example. The transparent electrodes 83, formed in the trench 81 which functions as an inter-pixel separation section that separates pixels, are provided so as to surround the PD 71 and are formed in a grid pattern so as to be interposed between multiple pixels 2. The grid-like transparent electrodes 83 are formed continuously in the effective pixel region 31 and the light-shielding pixel region 32.

[0075] The transparent electrode 73 is formed as a solid coating (formed over the entire surface) on the light incident side surface of the Si substrate 70, excluding the area open as a pad in the effective pixel area 31, the light-shielding pixel area 32, and the pad area 33. The transparent electrode 73 is connected to the transparent electrode 83 surrounding the effective pixels 31 in the effective pixel area 31, connected to the transparent electrode 83 surrounding the light-shielding pixels 32 in the light-shielding pixel area 32, and connected to the pad 101-1 in the pad area 33 via electrode 102. Pad 101-1 is provided as a pad connected to the transparent electrode 73, and pad 101-2 is provided as a pad connected to, for example, a logic circuit to send and receive signals.

[0076] When an external voltage is applied to pad 101-1, the voltage is applied to the transparent electrodes 83 located at each pixel via the transparent electrode 73 connected to pad 101-1.

[0077] Figure 8 shows another example of the planar configuration of the imaging device 1. In Figure 8, the explanation will mainly focus on the arrangement of the transparent electrodes 73 and 83. The transparent electrodes 83 formed in the trenches 81 formed between the pixels are provided to surround the PD 71, as in Figure 7, and are formed in a grid pattern so as to be interposed between multiple pixels 2. The grid-like transparent electrodes 83 are formed continuously in the effective pixel region 31 and the light-shielding pixel region 32.

[0078] The transparent electrodes 73 are formed in a grid pattern in the effective pixel region 31. In the example shown in Figure 8, the shape of the transparent electrodes 73 is shown in the region located at the edge of the screen of the pixel array 3 where pupil correction is applied. It also shows the case where the transparent electrodes 73 are formed in the same position as the light-shielding wall 74.

[0079] As explained with reference to Figures 4 and 5, at the edges of the screen, the light-shielding wall 74, color filter 75, and on-chip lens 76 are positioned so as to be offset toward the center of the screen relative to the PD 71. Therefore, in a plan view, as shown in Figure 8, the transparent electrodes 83 formed in a grid pattern and the transparent electrodes 73 formed in a grid pattern along the light-shielding wall 74 are in a misaligned positional relationship. Although not shown in the figures, at the center of the screen, the transparent electrodes 83 formed in a grid pattern and the transparent electrodes 73 formed in a grid pattern are in a coincident positional relationship.

[0080] It is also possible to provide the transparent electrode 73 in a position independent of the position of the light-shielding wall 74. In such a case, it is formed in the same position as the transparent electrode 83 and is formed in the same grid pattern as the transparent electrode 83.

[0081] The transparent electrode 73 is the area excluding the light-shielding pixel region 32 and the area of ​​the pad region 33 that is opened as a pad, and is formed as a solid coating on the light incident surface side of the Si substrate 70, as shown in Figure 7. The transparent electrode 73 formed in a grid pattern in the effective pixel region 31 is connected to the transparent electrode 73 formed as a solid coating in the light-shielding pixel region 32.

[0082] When the transparent electrode 73 in the light-shielding pixel region 32 is configured in the same position, size, and shape as the light-shielding film 91, it will look like Figure 8. It is also possible to configure the transparent electrode 73 in the light-shielding pixel region 32 with a different shape from the light-shielding film 91. In such a case, it will be formed with the same shape as the grid-like transparent electrode 73 formed in the effective pixel region 31.

[0083] The transparent electrode 73 is connected to the transparent electrode 83 surrounding the effective pixels 31 of the effective pixel region 31 at the point where they intersect in a plan view, connected to the transparent electrode 83 surrounding the light-shielding pixels 32 of the light-shielding pixel region 32, and connected to the pads 101-1 of the pad region 33 via the electrode 102.

[0084] When an external voltage is applied to pad 101-1, the voltage is applied to the transparent electrodes 83 located at each pixel via the transparent electrode 73 connected to pad 101-1.

[0085] The configuration shown in Figure 8 can be applied to transparent electrodes 73 made of transparent material, and can also be applied to electrodes made of non-transparent material. When a non-transparent material is used for the transparent electrodes 73, the transparent electrodes 73 located in the effective pixel region 31 can be provided as light-shielding walls 74, the transparent electrodes 73 located in the light-shielding pixel region 32 can be provided as light-shielding films 91, and the transparent electrodes 73 located in the pad region 33 can be provided as electrodes formed by extending the light-shielding films 91.

[0086] In this case, the transparent electrode 73 is omitted, and the light-shielding wall 74 and light-shielding film 91 are formed from a conductive material and used as electrodes. An example of the cross-sectional configuration of the imaging device 1 in this configuration is shown in Figure 9. In the example of the cross-sectional configuration of the imaging device 1 shown in Figure 9, the same reference numerals are used for parts that are the same as those in the example of the cross-sectional configuration of the imaging device 1 shown in Figure 3, and their explanations are omitted as appropriate.

[0087] The imaging device 1 shown in Figure 9 differs from the imaging device 1 shown in Figure 3 in that the transparent electrode 73 has been removed; otherwise, it is basically the same.

[0088] The effective pixels 31 located in the effective pixel region 31 are configured to include a PD 71 and a trench 81 that surrounds the PD 71 and functions as an inter-pixel separation region that separates the pixels. A sidewall film 82 made of SiO2 is formed inside the trench 81, and an electrode 201 is embedded inside the sidewall film 82. The electrode 201 may be formed using a transparent conductive material or a non-transparent conductive material.

[0089] A light-shielding wall 74 and a color filter 75 are provided on the light-incident surface side of the Si substrate 70, and an on-chip lens 76 is provided on the color filter 75. The effective pixel area 31 shown in Figure 9 is located at the edge of the screen and represents the part where pupil correction is applied, so the electrode 201 and the light-shielding wall 74 are positioned in offset positions. However, if the part of the cross-section is changed, there are overlapping parts between the electrode 201 and the light-shielding wall 74, and a voltage is applied to the electrode 201 via the light-shielding wall 74.

[0090] In the effective pixel region 31, the electrode 201 and the light-shielding wall 74 are each formed in a grid pattern in a plan view, as shown in Figure 8, and are configured to overlap (contact) in some areas. The electrode 201 and the light-shielding wall 74 can be formed from the same material, for example, tungsten (W).

[0091] A light-shielding film 91 is deposited in the light-shielding pixel region 32. The light-shielding film 91 is deposited on the light-incident surface side of the Si substrate 70. As shown in Figure 8, the light-shielding film 91 is deposited as a solid coating on the Si substrate 70 in a plan view. As shown in Figure 8, the light-shielding film 91 is configured to connect to a light-shielding wall 74 formed in a grid pattern at the boundary between the effective pixel region 31 and the light-shielding pixel region 32. In a cross-sectional view, as shown in Figure 9, the light-shielding film 91 is connected to an electrode 201 formed in a trench 81 that surrounds the light-shielding pixel 32.

[0092] The light-shielding wall 74 formed in the effective pixel region 31 and the light-shielding film 91 formed in the light-shielding pixel region 32 can be made of the same material, for example, tungsten (W). The light-shielding film 91 extends to the pad region 33 and is connected to the pad 101 formed in the pad region 33 via the electrode 102.

[0093] Thus, in the configuration of the imaging device 1 shown in Figures 8 and 9, the light-shielding wall 74 formed in the effective pixel region 31 extends to the pad region 33 via the light-shielding film 91 formed in the light-shielding pixel region 32, and is connected to the pads 101 in the pad region 33. By supplying power to the pads 101, it is supplied to the light-shielding film 91 via the electrodes 102, supplied to the light-shielding wall 74 via the light-shielding wall 74, and supplied to the electrodes 201 in each trench 81 via the light-shielding wall 74.

[0094] In this way, the voltage supplied to the pad 101 is supplied to the electrodes 201 provided on the side walls of each effective pixel 31 via the light-shielding wall 74 and light-shielding film 91 that extend to the effective pixel area 31.

[0095] <Regarding the manufacturing of the imaging device> The manufacturing of the imaging device 1 shown in Figure 3 will be explained with reference to Figures 10 and 11.

[0096] In step S11, a plurality of trenches 81 are formed in the Si substrate 70 in the regions that will become the effective pixel region 31 and the light-shielding pixel region 32.

[0097] In step S12, a sidewall film 82 is formed on the sidewall of the formed trench 81, and an oxide film 72 is formed on the light incident surface side of the Si substrate 71. The sidewall film 82 and the oxide film 72 can be formed using the same material, and if the same material is used, the sidewall film 82 and the oxide film 72 can be formed in the same process.

[0098] In step S12, a transparent material that will become the transparent electrode 83 is filled into the formed sidewall film 82 to form the transparent electrode 83. The transparent electrode 73 is formed on the oxide film 72 formed on the Si substrate 71. The transparent electrode 83 and the transparent electrode 73 can be formed using the same transparent material, and if the same material is used, the transparent electrode 83 and the transparent electrode 73 can be formed in the same process.

[0099] In step S13 (Figure 11), the pad region 33 is processed. The area of ​​the pad region 33 where the pad 101 will be formed is opened, and an insulating film 93 is deposited in the opened opening. The pad 101 is then formed using a material that will become the pad, such as aluminum (AL).

[0100] In step S14, an electrode 102 is formed to connect the pad 101 and the transparent electrode 73. In step S13, the transparent electrode 73 is removed in order to form the pad 101. Therefore, in step S13, the pad 101 and the transparent electrode 73 are not connected. Thus, in step S14, the pad 101 and the transparent electrode 73 are connected by the formation of the electrode 102. In step S14, in addition to the electrode 102, a light-shielding film 91 constituting the imaging device 1 is formed, and light-shielding walls 74, color filters 75, on-chip lenses 96, etc. are formed, thereby manufacturing the imaging device 1 shown in Figure 3.

[0101] When manufacturing the imaging device 1 having the configuration shown in Figure 9, it may be necessary to modify the process as appropriate, for example, in process S12 when the transparent electrode 83 and transparent electrode 73 are formed, by using tungsten to form the electrode 201, light-shielding wall 74, light-shielding film 91, etc., but it can be manufactured using basically the same process.

[0102] <Regarding the configuration of the pad> The configuration of the pad 101 will be explained below. Figure 12 shows an example of the cross-sectional configuration of the pad 101. In the following explanation, configurations other than those of the pad 101 shown in Figures 3 and 9 will be used as examples. In the following explanation, the configuration of the imaging device 1 shown in Figure 3, in other words, the configuration in which the transparent electrode 73 extends to the pad region 33 will be used as an example.

[0103] Figure 12 shows an example of a pad 101, sometimes referred to as a REOL PAD. A transparent electrode 73 is formed in the area opened in the pad region 33, extending from the effective pixel region 31. The pad 101 is formed so that it directly contacts the transparent electrode 73 formed on the Si substrate 70 at the opening 301. In this way, the pad 101 can be configured to be directly provided on the transparent electrode 73.

[0104] Figure 13 shows another example of a pad 101, also known as a REOL PAD. The pad 101 shown in Figure 13 is provided within a Si substrate 70. The pad 101 is formed within an insulating film 93 that is deposited in an area where the Si substrate 70 has been excavated. A transparent electrode 73, which extends from the effective pixel area 31, is deposited on a part of the surface of the pad 101 that is open. The pad 101 and the transparent electrode 73 are formed such that the transparent electrode 73 deposited on the Si substrate 70 is in direct contact with the pad 101 formed within the Si substrate 70. In this way, the pad 101 can be configured to be directly provided beneath the transparent electrode 73.

[0105] Figure 14 shows an example of a pad 101, also known as a FEOL PAD. The pad 101 shown in Figure 14 is provided within a Si substrate 70. The pad 101 is formed in a region that has been excavated in the Si substrate 70. The pad 101 shown in Figure 14 consists of a pad 101a provided on the bottom surface of the opening, a pad 101b provided on the side wall, and a pad 101c connecting the pad 101b to the transparent electrode 73.

[0106] When the pad 101 is formed in the open portion, the material that will become the pad 101, such as aluminum, is left on the side wall and the transparent electrode 73, thereby forming pads 101b and 101c. Figure 14 shows an example in which pads 101b and 101c are formed on the left and right side walls of pad 101a, but it is also possible to have a configuration in which they are formed on only one of the side walls.

[0107] Figure 15 shows another example of a pad 101, also known as a FEOL PAD. The pad 101 shown in Figure 15 is provided on the bottom surface of an opening 311 into which the Si substrate 70 is carved. The pad 101 is formed on the Si substrate 70, on the bottom surface of the carved area. The pad 101 shown in Figure 15 is the lower side of the pad 101 and is connected to an electrode 322 provided in the Si substrate 70. The electrode 322 is connected to an electrode 321 provided in the pad area 33.

[0108] When forming the pad 101 shown in Figure 15, the pad region 33 is also provided with an electrode 321 formed from the trench 81, sidewall film 82, and transparent electrode 73 provided in the effective pixel region 31 and light-shielding pixel region 32. Referring to the plan view shown in the lower part of Figure 15, the electrode 321 is provided so as to surround the opening 311 where the pad 101 is provided, and the electrode 322 is formed in a cross shape within the rectangular electrode 321. The electrodes 321 and 322 are formed in this shape and are connected to each other.

[0109] Since electrode 321 is connected to transparent electrode 73 which extends to the pad region 33, electrode 322 is also connected to transparent electrode 73. Pad 101 is connected to electrode 322 at its bottom surface, and is connected to transparent electrode 73 via electrode 322.

[0110] Figure 16 shows an example of a case where a pad 101 is formed in the wiring layer 77. The pad 101 shown in Figure 16 is formed embedded within the wiring layer 77 and is formed with a portion open. The pad 101 is formed within the wiring layer 77, and a portion of it is exposed when the opening 332 is formed.

[0111] The Si substrate 70 is also provided with electrodes 331 having a Y configuration similar to the electrodes formed by the trenches 81, sidewall films 82, and transparent electrodes 73 provided in the effective pixel region 31 and light-shielding pixel region 32, in the pad region 33, and these electrodes 331 extend up to the upper surface of the pads 101 provided in the wiring layer 77. Referring to the plan view shown in the lower part of Figure 16, the electrodes 331 are provided so as to surround the opening 332 in which the pads 101 are exposed.

[0112] Since the electrode 331 is connected to the transparent electrode 73 which extends to the pad region 33, the pad 101 connected to the electrode 331 is also connected to the transparent electrode 73 via the electrode 331.

[0113] Figure 17 shows another example of a case where a pad 101 is formed in the wiring layer 77. The pad 101 shown in Figure 17 is formed embedded in the wiring layer 77 and is formed with a part of it open. After the pad 101 is formed in the wiring layer 77, an opening 341 is formed, so that a part of it is exposed.

[0114] The pad 101 shown in Figure 17 consists of a pad 101a that is exposed on the bottom surface of the opening 341, a pad 101b that is provided on the side wall, and a pad 101c that connects the pad 101b to the transparent electrode 73.

[0115] After the opening 341 is formed, pad 101 is formed by forming pad 101b on the side wall using the same material as pad 101a, for example, aluminum, and then forming pad 101c to connect pad 101b to the transparent electrode 73. Figure 17 shows an example in which pad 101b and pad 101c are formed on the left side wall relative to pad 101a, but a configuration in which they are formed on both the left and right side walls is also possible.

[0116] Figure 18 shows another example of a case where a pad 101 is formed in the wiring layer 77, and is a diagram showing an example of the configuration of a pad referred to as a BEOL PAD or LOGIC PAD. The pad 101 shown in Figure 18 is formed embedded in the wiring layer 77 and is formed with a part of it open. After the pad 101 is formed in the wiring layer 77, an opening 353 is formed, so that a part of it is exposed.

[0117] The pad 101 and the transparent electrode 73 formed on the Si substrate 70 are connected by a via 351. The via 351 penetrates the Si substrate 70 and extends to the upper surface of the pad 101 within the wiring layer 77. The via 351 is covered with an insulating film 352.

[0118] Figure 19 shows another example of a case where a pad 101 is formed in the wiring layer 77, and is a diagram showing other configuration examples of pads, such as BEOL PAD and LOGIC PAD. The pad 101 shown in Figure 19 is formed embedded in the wiring layer 77 and is formed with a part of it open. After the pad 101 is formed in the wiring layer 77, an opening 363 is formed, so that a part of it is exposed.

[0119] The pad 101 and the transparent electrode 73 formed on the Si substrate 70 are connected by vias 361 formed in the wiring layer 77 and electrodes 371 formed in the Si substrate 70. The interior of the via 361 is filled with the same material as the pad 101, and its periphery is covered with an insulating film 362. The electrode 371 has a similar configuration to the electrodes composed of trenches 81, sidewall films 82, and transparent electrodes 73 provided in the effective pixel region 31 and the light-shielding pixel region 32.

[0120] The via 361 is formed to a position that extends from the upper surface of the pad 101 in the wiring layer 77 to the bottom surface of the Si substrate 70, or to the interior of the Si substrate 70. The electrode 371 is formed to a position that substantially penetrates the Si substrate 70 and is provided to a position that connects to the via 361. The electrode 371 is connected to the transparent electrode 73, the via 361 is connected to the electrode 371, and the via 361 is connected to the pad 101, so the pad 101 is also connected to the transparent electrode 73.

[0121] Figure 20 shows another example of a case where a pad 101 is formed in the wiring layer 77. The pad 101 shown in Figure 20 is formed embedded within the wiring layer 77, with a portion of it open. After the pad 101 is formed within the wiring layer 77, an opening 363 is formed, causing a portion of the pad 101 to be exposed.

[0122] The pad 101 is formed within the wiring layer 77 and connected to the wiring 381 formed within the wiring layer 77. The wiring 381 may be a via or a guard ring formed within the wiring layer 77. A second guard ring 34 is formed on the Si substrate 70.

[0123] The second guard ring 34 has a configuration similar to that of the electrodes formed by the trench 81, sidewall film 82, and transparent electrode 73 provided in the effective pixel area 31 and the light-shielding pixel area 32. In this embodiment, the second guard ring 34 has a configuration that functions both as a guard ring and as an electrode.

[0124] The second guard ring 34 is connected to the transparent electrode 73 and extends from the transparent electrode 73 to the point where the Si substrate 70 and the wiring layer 77 make contact. The wiring 381 extends from the upper surface of the pad 101 to the point where the Si substrate 70 and the wiring layer 77 make contact. The pad 101 is connected to the transparent electrode 73 via the wiring 381 and the second guard ring 34.

[0125] Figure 21 shows another example of a case where a pad 101 is formed in the wiring layer 77. The pad 101 shown in Figure 21 is formed embedded in the wiring layer 77 and is partially open. After the pad 101 is formed in the wiring layer 77, an opening 363 is formed, causing a portion of the pad 101 to be exposed.

[0126] The pad 101 is formed within the wiring layer 77 and connected to the wiring 391 formed within the wiring layer 77. The wiring 391 may be a via or a guard ring formed within the wiring layer 77. A second guard ring 34 is formed on the Si substrate 70. The second guard ring 34 has a configuration similar to that of the electrodes formed by the trench 81, sidewall film 82, and transparent electrode 73 provided in the effective pixel region 31 and the light-shielding pixel region 32.

[0127] The second guard ring 34 is connected to the transparent electrode 73 and extends from the transparent electrode 73 through the Si substrate 70 to the position where the wiring 391 in the wiring layer 77 is formed. The wiring 391 is formed from the upper surface of the pad 101 to the position reached by the second guard ring 34. The pad 101 is connected to the transparent electrode 73 via the wiring 391 and the second guard ring 34.

[0128] Thus, various configurations can be applied to the pad 101, and in any configuration, the pad 101 and the transparent electrode 83 placed on the effective pixel 31 can be connected by the transparent electrode 73 formed on the Si substrate 70.

[0129] <Examples of application to electronic devices> This technology can be applied to all electronic devices that use an image sensor in the image acquisition unit (photoelectric conversion unit), such as imaging devices like digital still cameras and video cameras, portable terminal devices with imaging functions, and photocopiers that use an image sensor in the image reading unit. The image sensor may be formed as a single chip, or it may be in the form of a module with imaging functions in which the imaging unit and the signal processing unit or optical system are packaged together.

[0130] Figure 22 is a block diagram showing an example configuration of an imaging device as an electronic device to which this technology is applied. The imaging device 1000 in Figure 22 includes an optical unit 1001 consisting of a lens group and the like, an image sensor (imaging device) 1002, and a DSP (Digital Signal Processor) circuit 1003 which is a camera signal processing circuit. The imaging device 1000 also includes a frame memory 1004, a display unit 1005, a recording unit 1006, an operation unit 1007, and a power supply unit 1008. The DSP circuit 1003, frame memory 1004, display unit 1005, recording unit 1006, operation unit 1007, and power supply unit 1008 are interconnected via a bus line 1009.

[0131] The optical unit 1001 captures incident light (image light) from the subject and forms an image on the imaging surface of the image sensor 1002. The image sensor 1002 converts the amount of light from the incident light formed on the imaging surface by the optical unit 1001 into an electrical signal on a pixel-by-pixel basis and outputs it as a pixel signal.

[0132] The display unit 1005 is composed of a thin display such as an LCD (Liquid Crystal Display) or an organic EL (Electro Luminescence) display, and displays video or still images captured by the image sensor 1002. The recording unit 1006 records the video or still images captured by the image sensor 1002 onto a recording medium such as a hard disk or semiconductor memory.

[0133] The operation unit 1007 issues operation commands for various functions of the imaging device 1000 under the user's input. The power supply unit 1008 appropriately supplies various power sources to the DSP circuit 1003, frame memory 1004, display unit 1005, recording unit 1006, and operation unit 1007.

[0134] The imaging device 1 described above can be applied to a part of the imaging device shown in Figure 22.

[0135] <Examples of application to endoscopic surgical systems> The technology disclosed herein (this technology) can be applied to various products. For example, the technology disclosed herein may be applied to endoscopic surgical systems.

[0136] Figure 23 is a diagram showing an example of a schematic configuration of an endoscopic surgical system to which the technology described herein (the technology) may be applied.

[0137] Figure 23 illustrates a surgeon (physician) 11131 performing surgery on a patient 11132 on a patient bed 11133 using an endoscopic surgical system 11000. As shown in the figure, the endoscopic surgical system 11000 consists of an endoscope 11100, other surgical instruments 11110 such as an insufflation tube 11111 and an energy treatment device 11112, a support arm device 11120 for supporting the endoscope 11100, and a cart 11200 equipped with various devices for endoscopic surgery.

[0138] The endoscope 11100 consists of a barrel 11101, the tip of which is inserted into the body cavity of the patient 11132 for a predetermined length, and a camera head 11102 connected to the base end of the barrel 11101. In the illustrated example, the endoscope 11100 is shown as a so-called rigid endoscope having a rigid barrel 11101, but the endoscope 11100 may also be configured as a so-called flexible endoscope having a flexible barrel.

[0139] An opening into which an objective lens is fitted is provided at the tip of the microscope tube 11101. A light source device 11203 is connected to the endoscope 11100, and the light generated by the light source device 11203 is guided to the tip of the microscope tube by a light guide extending inside the microscope tube 11101, and is irradiated through the objective lens towards the object to be observed inside the body cavity of the patient 11132. The endoscope 11100 may be a straight-viewing endoscope, an oblique-viewing endoscope, or a side-viewing endoscope.

[0140] The camera head 11102 contains an optical system and an image sensor. Reflected light from the object being observed (observation light) is focused onto the image sensor by the optical system. The image sensor converts the observation light into electrical signals, generating an electrical signal corresponding to the observation light, i.e., an image signal corresponding to the observed image. This image signal is transmitted as RAW data to the camera control unit (CCU) 11201.

[0141] The CCU 11201 is composed of a CPU (Central Processing Unit), a GPU (Graphics Processing Unit), and other components, and comprehensively controls the operation 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 image processing operations on that image signal, such as development processing (demosaic processing), to display an image based on that image signal.

[0142] The display device 11202 displays an image based on an image signal that has been processed by the CCU 11201, under control from the CCU 11201.

[0143] The light source device 11203 is composed of a light source such as an LED (light-emitting diode) and supplies illumination light to the endoscope 11100 when photographing the surgical area, etc.

[0144] The input device 11204 is an input interface for the endoscopic surgical system 11000. The user can input various types of information and instructions to the endoscopic surgical system 11000 via the input device 11204. For example, the user can input instructions to change the imaging conditions (type of light, magnification, focal length, etc.) of the endoscope 11100.

[0145] The treatment instrument control device 11205 controls the drive of the energy treatment instrument 11112 for purposes such as tissue cauterization, incision, or blood vessel sealing. The insufflation device 11206 injects gas into the body cavity of the patient 11132 via the insufflation tube 11111 to inflate the body cavity for the purpose of securing a field of view by the endoscope 11100 and securing the operator's workspace. The recorder 11207 is a device capable of recording various information related to the surgery. The printer 11208 is a device capable of printing various information related to the surgery in various formats such as text, images, or graphs.

[0146] The light source device 11203 that supplies illumination light to the endoscope 11100 when photographing the surgical area can be configured as a white light source consisting of, for example, an LED, a laser light source, or a combination thereof. When the white light source is configured as a combination of RGB laser light sources, the output intensity and output timing of each color (each wavelength) can be controlled with high precision, so the white balance of the captured image can be adjusted in the light source device 11203. In this case, it is also possible to capture images corresponding to each of the RGB colors in time-division by irradiating the observation target with laser light from each of the RGB laser light sources in time-division and controlling the drive of the image sensor of the camera head 11102 in synchronization with the irradiation timing. According to this method, a color image can be obtained without providing a color filter on the image sensor.

[0147] Furthermore, the light source device 11203 may be controlled to change the intensity of the light it outputs at predetermined time intervals. By controlling the drive of the image sensor of the camera head 11102 in synchronization with the timing of the change in light intensity, images can be acquired in time-division order, and these images can be combined to generate high dynamic range images without so-called black crushing and white clipping.

[0148] Furthermore, the light source device 11203 may be configured to supply light in a predetermined wavelength band corresponding to special light observation. In special light observation, for example, by utilizing the wavelength dependence of light absorption in body tissue and irradiating with narrow-band light compared to the irradiation light used during normal observation (i.e., white light), so-called narrow-band imaging is performed to image predetermined tissues such as blood vessels on the surface of mucosa with high contrast. Alternatively, in special light observation, fluorescence observation may be performed to obtain an image from fluorescence generated by irradiation with excitation light. In fluorescence observation, excitation light is irradiated onto body tissue and fluorescence from the body tissue is observed (autofluorescence observation), or a reagent such as indocyanine green (ICG) is injected into body tissue and excitation light corresponding to the fluorescence wavelength of the reagent is irradiated onto the body tissue to obtain a fluorescence image. The light source device 11203 may be configured to supply narrow-band light and / or excitation light corresponding to such special light observation.

[0149] Figure 24 is a block diagram showing an example of the functional configuration of the camera head 11102 and CCU 11201 shown in Figure 23.

[0150] The camera head 11102 includes 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 includes 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.

[0151] The lens unit 11401 is an optical system provided at the connection point 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 then incident on the lens unit 11401. The lens unit 11401 is composed of a combination of multiple lenses, including a zoom lens and a focus lens.

[0152] The imaging unit 11402 may consist of one image sensor (a so-called single-chip type) or multiple image sensors (a so-called multi-chip type). If the imaging unit 11402 is configured as a multi-chip type, for example, each image sensor may generate image signals corresponding to RGB, and these may be combined to obtain a color image. Alternatively, the imaging unit 11402 may be configured to have a pair of image sensors for acquiring image signals for the right eye and left eye, respectively, corresponding to 3D (dimensional) display. By performing 3D display, the surgeon 11131 can more accurately grasp the depth of the biological tissue in the surgical area. In addition, if the imaging unit 11402 is configured as a multi-chip type, multiple lens units 11401 may be provided corresponding to each image sensor.

[0153] Furthermore, the imaging unit 11402 does not necessarily have to be located on the camera head 11102. For example, the imaging unit 11402 may be located inside the lens barrel 11101, directly behind the objective lens.

[0154] The drive unit 11403 is composed of actuators and, under control from the camera head control unit 11405, moves the zoom lens and focus lens of the lens unit 11401 along the optical axis by a predetermined distance. This allows the magnification and focus of the image captured by the imaging unit 11402 to be adjusted as appropriate.

[0155] The communication unit 11404 is composed of communication devices for sending and receiving various types of information with the CCU 11201. The communication unit 11404 transmits the image signal obtained from the imaging unit 11402 as RAW data to the CCU 11201 via the transmission cable 11400.

[0156] Furthermore, the communication unit 11404 receives a control signal from the CCU 11201 to control the drive of the camera head 11102 and supplies it to the camera head control unit 11405. The control signal includes information about imaging conditions, such as information to specify the frame rate of the captured image, information to specify the exposure value at the time of imaging, and / or information to specify the magnification and focus of the captured image.

[0157] The imaging conditions such as frame rate, exposure value, magnification, and focus may be specified by the user as appropriate, or they 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 so-called AE (Auto Exposure), AF (Auto Focus), and AWB (Auto White Balance) functions.

[0158] The camera head control unit 11405 controls the driving of the camera head 11102 based on the control signal received from the CCU 11201 via the communication unit 11404.

[0159] The communication unit 11411 is comprised of a communication device for sending and receiving various types of information with the camera head 11102. The communication unit 11411 receives image signals transmitted from the camera head 11102 via the transmission cable 11400.

[0160] Furthermore, the communication unit 11411 transmits control signals to the camera head 11102 to control the driving of the camera head 11102. Image signals and control signals can be transmitted by telecommunications, optical communications, etc.

[0161] The image processing unit 11412 performs various image processing operations on the image signal, which is RAW data transmitted from the camera head 11102.

[0162] The control unit 11413 performs various controls related to imaging the surgical area, etc., by the endoscope 11100, and the display of the images obtained from imaging the surgical area, etc. For example, the control unit 11413 generates a control signal to control the driving of the camera head 11102.

[0163] Furthermore, the control unit 11413 displays the captured image showing the surgical area, etc., on the display device 11202 based on the image signal processed 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 instruments such as forceps, specific biological sites, bleeding, mist when using the energy treatment device 11112, etc., by detecting the shape and color of the edges of objects included in the captured image. When the control unit 11413 displays the captured image on the display device 11202, it may use the recognition results to superimpose various surgical support information onto the image of the surgical area. 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.

[0164] The transmission cable 11400 connecting the camera head 11102 and the CCU 11201 is an electrical signal cable compatible with electrical signal communication, an optical fiber compatible with optical communication, or a composite cable thereof.

[0165] In the illustrated example, communication was performed via a wired connection using a transmission cable 11400, but communication between the camera head 11102 and the CCU 11201 may be performed wirelessly.

[0166] <Examples of application to mobile devices> The technology disclosed herein (this technology) can be applied to various products. For example, the technology disclosed herein may be implemented as a device mounted on any type of mobile device such as automobiles, electric vehicles, hybrid electric vehicles, motorcycles, bicycles, personal mobility devices, airplanes, drones, ships, and robots.

[0167] Figure 25 is a block diagram showing a schematic configuration example of a vehicle control system, which is an example of a mobile control system to which the technology described herein may be applied.

[0168] The vehicle control system 12000 comprises a plurality of electronic control units connected via a communication network 12001. In the example shown in Figure 25, the vehicle control system 12000 includes a drive system control unit 12010, a body system control unit 12020, an external information detection unit 12030, an internal information detection unit 12040, and an integrated control unit 12050. The functional configuration of the integrated control unit 12050 is shown in the figure, which includes a microcomputer 12051, an audio / image output unit 12052, and an in-vehicle network interface 12053.

[0169] The drivetrain control unit 12010 controls the operation of devices related to the vehicle's drivetrain according to various programs. For example, the drivetrain control unit 12010 functions as a control device for a drivetrain generating device that generates driving force for the vehicle, such as an internal combustion engine or a drive motor; a drivetrain transmission mechanism that transmits driving force to the wheels; a steering mechanism that adjusts the steering angle of the vehicle; and a braking device that generates braking force for the vehicle.

[0170] The body system control unit 12020 controls the operation of various devices mounted on 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 system, or various lamps such as headlights, reverse lights, brake lights, turn signals, or fog lights. In this case, the body system control unit 12020 may receive radio waves transmitted from a portable device that replaces a key or signals from various switches. The body system control unit 12020 receives these radio waves or signals and controls the vehicle's door lock system, power window system, lamps, etc.

[0171] The external information detection unit 12030 detects information from outside the vehicle equipped with the vehicle control system 12000. For example, an imaging unit 12031 is connected to the external information detection unit 12030. The external information detection unit 12030 causes the imaging unit 12031 to capture images of the outside of the vehicle and receives the captured images. Based on the received images, the external information detection unit 12030 may perform object detection processing such as detecting people, cars, obstacles, signs, or characters on the road surface, or distance detection processing.

[0172] The imaging unit 12031 is a light 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.

[0173] The in-vehicle information detection unit 12040 detects information inside the vehicle. The in-vehicle information detection unit 12040 is connected to, for example, a driver status detection unit 12041 that detects the driver's state. The driver status detection unit 12041 includes, for example, a camera that captures images of the driver, and the in-vehicle information detection unit 12040 may calculate the driver's level of fatigue or concentration, or determine whether the driver is drowsy, based on the detection information input from the driver status detection unit 12041.

[0174] The microcomputer 12051 can calculate control target values ​​for the drive force generator, steering mechanism, or braking device based on information inside and outside the vehicle acquired by the external information detection unit 12030 or the internal 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 ADAS (Advanced Driver Assistance System) functions, including collision avoidance or impact mitigation, following driving based on distance between vehicles, maintaining vehicle speed, vehicle collision warning, or vehicle lane departure warning.

[0175] Furthermore, the microcomputer 12051 can 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 information about the vehicle's surroundings acquired by the external information detection unit 12030 or the internal information detection unit 12040.

[0176] Furthermore, the microcomputer 12051 can output control commands to the body system control unit 12020 based on external information acquired by the external information detection unit 12030. For example, the microcomputer 12051 can control the headlights according to the position of a preceding or oncoming vehicle detected by the external information detection unit 12030, and perform coordinated control aimed at reducing glare, such as switching from high beams to low beams.

[0177] The audio-image output unit 12052 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 shown in Figure 25, the output devices include 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 onboard display and a head-up display.

[0178] Figure 26 shows an example of the installation position of the imaging unit 12031.

[0179] In Figure 26, the imaging unit 12031 includes imaging units 12101, 12102, 12103, 12104, and 12105.

[0180] The imaging units 12101, 12102, 12103, 12104, and 12105 are installed, for example, on the front nose, side mirrors, rear bumper, back door, and the upper part of the windshield inside the vehicle 12100. The imaging unit 12101 installed on the front nose and the imaging unit 12105 installed on the upper part of the windshield inside the vehicle mainly acquire images of the front of the vehicle 12100. The imaging units 12102 and 12103 installed on the side mirrors mainly acquire images of the sides of the vehicle 12100. The imaging unit 12104 installed on the rear bumper or back door mainly acquires images of the rear of the vehicle 12100. The imaging unit 12105 installed on the upper part of the windshield inside the vehicle is mainly used for detecting preceding vehicles, pedestrians, obstacles, traffic lights, traffic signs, or lanes.

[0181] Figure 26 shows an example of the imaging range of imaging units 12101 to 12104. Imaging range 12111 indicates the imaging range of imaging unit 12101 located on the front nose, imaging ranges 12112 and 12113 indicate the imaging ranges of imaging units 12102 and 12103 located on the side mirrors, respectively, and imaging range 12114 indicates the imaging range of imaging unit 12104 located on the rear bumper or back door. For example, by superimposing the image data captured by imaging units 12101 to 12104, an overhead view image of the vehicle 12100 can be obtained.

[0182] At least one of the imaging units 12101 to 12104 may have a function for acquiring distance information. For example, at least one of the imaging units 12101 to 12104 may be a stereo camera consisting of multiple image sensors, or an image sensor having pixels for phase difference detection.

[0183] For example, the microcomputer 12051, based on distance information obtained from the imaging units 12101 to 12104, can determine the distance to each object within the imaging range 12111 to 12114 and the temporal change of this distance (relative speed to the vehicle 12100). In particular, it can extract the closest object on the vehicle 12100's path that is traveling in approximately the same direction as the vehicle 12100 at a predetermined speed (e.g., 0 km / h or more) as the preceding vehicle. Furthermore, the microcomputer 12051 can set a predetermined distance to be maintained before the preceding vehicle and perform automatic braking control (including follow-and-stop control) and automatic acceleration control (including follow-and-start control), etc. In this way, cooperative control aimed at autonomous driving, where the vehicle drives autonomously without driver intervention, can be performed.

[0184] For example, the microcomputer 12051 can use distance information obtained from imaging units 12101 to 12104 to classify and extract three-dimensional object data related to three-dimensional objects, such as motorcycles, passenger cars, large vehicles, pedestrians, utility poles, and other three-dimensional objects, and use this data for automatic obstacle avoidance. For example, the microcomputer 12051 identifies 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 the collision risk, which indicates the degree of risk of collision with each obstacle. If the collision risk is above a set value and there is a possibility of collision, the microcomputer 12051 can provide driving assistance to avoid collisions by outputting a warning to the driver via the audio speaker 12061 or the display unit 12062, or by performing forced deceleration or evasive steering via the drive system control unit 12010.

[0185] At least one of the imaging units 12101 to 12104 may be an infrared camera that detects infrared light. For example, the microcomputer 12051 can recognize pedestrians by determining whether or not pedestrians are present in the images captured by the imaging units 12101 to 12104. Such pedestrian recognition is performed, for example, by a procedure to extract feature points from the images captured by the imaging units 12101 to 12104 as infrared cameras, and a procedure to perform pattern matching on a series of feature points that indicate the contour of an object to determine whether or not it is a pedestrian. When the microcomputer 12051 determines that a pedestrian is present in the images captured by the imaging units 12101 to 12104 and recognizes a pedestrian, the audio-image output unit 12052 controls the display unit 12062 to superimpose a rectangular contour line for emphasis on the recognized pedestrian. The audio-image output unit 12052 may also control the display unit 12062 to display an icon indicating a pedestrian at a desired position.

[0186] In this specification, "system" refers to an entire apparatus composed of multiple devices.

[0187] Furthermore, the effects described herein are merely illustrative and not limiting, and other effects may also occur.

[0188] It should be noted that the embodiments of this technology are not limited to those described above, and various modifications are possible without departing from the spirit of this technology.

[0189] Furthermore, this technology can also take the following configurations: (1) An imaging device comprising: a semiconductor substrate on which a photoelectric conversion unit is provided for each pixel; a first electrode provided in a trench separating the pixels in the semiconductor substrate; a second electrode provided on the light incident surface side of the semiconductor substrate; and a pad to which a terminal for applying a voltage is connected, wherein the second electrode is connected to the first electrode and extends to the pad. (2) The imaging device according to (1), wherein the first electrode and the second electrode are made of the same conductive material. (3) The imaging device according to (2), wherein the conductive material is a transparent electrode material. (4) The imaging device according to (3), wherein the second electrode is formed on the entire surface of the light incident surface. (5) The imaging apparatus according to any one of (1) to (4), wherein the semiconductor substrate comprises an effective pixel region where an effective pixel is arranged, a light-shielding pixel region where a light-shielding pixel is arranged, and a pad region where the pad is arranged, and the second electrode formed in the effective pixel region extends through the light-shielding pixel region to the pad region. (6) The imaging apparatus according to (5), wherein the second electrode is formed between a light-shielding film arranged on the light-shielding pixel and the photoelectric conversion unit. (7) The imaging apparatus according to any one of (2) to (6), further comprising a light-shielding wall on the light incident surface side of the semiconductor substrate, wherein the light-shielding wall is formed of the conductive material. (8) The imaging apparatus according to (7), wherein the light-shielding film arranged on the light-shielding pixel is formed of the same conductive material as the light-shielding wall. (9) The imaging apparatus according to any one of (1) to (8), wherein the first electrode and the second electrode are each formed in a grid pattern in a plan view. (10) The imaging device according to (9), wherein pupil correction is applied, and the first electrode formed in a grid pattern and the second electrode formed in a grid pattern are positioned at offset positions on the high image height side and connected at the portion where they intersect in a plan view. (11) The imaging device according to any one of (1) to (10), wherein the pad is provided above or below the second electrode and is directly connected to the second electrode.(12) The imaging apparatus according to any one of (1) to (10), wherein the pad is formed on the bottom surface of a region in which the semiconductor substrate is excavated, and an electrode connecting the pad and the second electrode is provided on the side surface of the excavated region. (13) The imaging apparatus according to any one of (1) to (10), further comprising a third electrode connected to the second electrode in the semiconductor substrate, and a fourth electrode connected to the third electrode, wherein the pad is formed on the bottom surface of a region in which the semiconductor substrate is excavated, and the fourth electrode is connected at the bottom surface of the pad. (14) The imaging apparatus according to any one of (1) to (10), further comprising a wiring layer on the surface opposite to the light incident surface, wherein the pad is provided in the wiring layer, and the pad and the second electrode are connected via a via. (15) The imaging apparatus according to (14), wherein the via is connected to an electrode having the same configuration as the first electrode formed in the semiconductor substrate. (16) The imaging apparatus according to any one of (1) to (10), further comprising a wiring layer on the surface opposite to the light incident surface, wherein the pad is provided within the wiring layer, and the pad and the second electrode are connected to an electrode having the same configuration as the first electrode formed in the semiconductor substrate and within the wiring layer. (17) The imaging apparatus according to any one of (1) to (10), further comprising a wiring layer on the surface opposite to the light incident surface, wherein the pad is provided within the wiring layer, the upper part of the pad is open, and an electrode connecting the pad and the second electrode is provided on the side of the open region. (18) The imaging apparatus according to any one of (1) to (10), wherein the electrode connecting the second electrode and the pad includes a guard ring. (19) An electronic device comprising: a semiconductor substrate on which a photoelectric conversion unit is provided for each pixel; a first electrode provided in a trench separating the pixels in the semiconductor substrate; a second electrode provided on the light incident surface side of the semiconductor substrate; a pad to which a terminal for applying a voltage is connected, wherein the second electrode is connected to the first electrode and extends to the pad; and a processing unit for processing signals from the imaging device.

[0190] 1 Imaging device, 2 Pixel, 3 Pixel array section, 4 Vertical drive circuit, 5 Column signal processing circuit, 6 Horizontal drive circuit, 7 Output circuit, 8 Control circuit, 9 Vertical signal line, 10 Pixel drive wiring, 11 Horizontal signal line, 12 Semiconductor substrate, 13 Input / output terminal, 31 Effective pixel, 32 Light-shielding pixel, 33 Pad area, 34 Second guard ring, 35 First guard ring, 51 Pixel array section, 70 Si substrate, 71 Si substrate, 72 Oxide film, 73 Transparent electrode, 74 Light-shielding wall, 75 Color filter, 76 On-chip lens, 77 Wiring layer, 81 Trench, 82 Sidewall film, 83 Transparent electrode, 91 Light-shielding film, 92 Oxide film, 93 Insulating film, 96 On-chip lens, 101 Pad, 102 Electrode, 111 Barrier metal, 112 Oxide film, 113 Dielectric film, 121 Aperture, 201 Electrode, 301 Aperture, 311 Aperture, 321 Electrode, 322 Electrode, 331 Electrode, 332 Aperture, 341 Aperture, 351 Via, 352 Insulating film, 353 Aperture, 361 Via, 362 Insulating film, 363 Aperture, 371 Electrode, 381 Wiring, 391 Wiring

Claims

1. An imaging device comprising: a semiconductor substrate on which a photoelectric conversion unit is provided for each pixel; a first electrode provided in a trench separating the pixels in the semiconductor substrate; a second electrode provided on the light incident surface side of the semiconductor substrate; and a pad to which a terminal for applying a voltage is connected, wherein the second electrode is connected to the first electrode and extends to the pad.

2. The imaging apparatus according to claim 1, wherein the first electrode and the second electrode are made of the same conductive material.

3. The imaging apparatus according to claim 2, wherein the conductive material is a transparent electrode material.

4. The imaging apparatus according to claim 3, wherein the second electrode has a film formed on the entire surface of the light incident surface.

5. The imaging apparatus according to claim 1, wherein the semiconductor substrate comprises an effective pixel region where effective pixels are arranged, a light-shielding pixel region where light-shielding pixels are arranged, and a pad region where the pad is arranged, and the second electrode formed in the effective pixel region extends through the light-shielding pixel region to the pad region.

6. The imaging apparatus according to claim 5, wherein the second electrode is formed between the light-shielding film disposed on the light-shielding pixel and the photoelectric conversion unit.

7. The imaging apparatus according to claim 2, further comprising a light-shielding wall on the light incident surface side of the semiconductor substrate, wherein the light-shielding wall is formed of the conductive material.

8. The imaging apparatus according to claim 7, wherein the light-shielding film disposed on the light-shielding pixel is formed of the same conductive material as the light-shielding wall.

9. The imaging apparatus according to claim 1, wherein each of the first electrode and the second electrode is formed in a grid pattern in a plan view.

10. The imaging apparatus according to claim 9, wherein pupil correction is applied, and the first electrode formed in a grid pattern and the second electrode formed in a grid pattern are positioned at offset locations on the high image height side and connected at the portion where they intersect in a plan view.

11. The imaging apparatus according to claim 1, wherein the pad is provided above or below the second electrode and is directly connected to the second electrode.

12. The imaging apparatus according to claim 1, wherein the pad is formed on the bottom surface of the region in which the semiconductor substrate is excavated, and the side surface of the excavated region has an electrode connecting the pad and the second electrode.

13. The imaging apparatus according to claim 1, further comprising a third electrode connected to the second electrode within the semiconductor substrate, and a fourth electrode connected to the third electrode, wherein the pad is formed on the bottom surface of a region in which the semiconductor substrate is excavated, and the fourth electrode is connected on the bottom surface of the pad.

14. The imaging apparatus according to claim 1, further comprising a wiring layer on the surface opposite to the light incident surface, wherein the pad is provided within the wiring layer, and the pad and the second electrode are connected via vias.

15. The imaging apparatus according to claim 14, wherein the via is connected to an electrode having the same configuration as the first electrode formed in the semiconductor substrate.

16. The imaging apparatus according to claim 1, further comprising a wiring layer on the surface opposite to the light incident surface, wherein the pad is provided within the wiring layer, and the pad and the second electrode are connected to an electrode having the same configuration as the first electrode formed within the semiconductor substrate and the wiring layer.

17. The imaging apparatus according to claim 1, further comprising a wiring layer on a surface opposite to the light incident surface, wherein the pad is provided within the wiring layer, the upper part of the pad is open, and an electrode connecting the pad and the second electrode is provided on the side of the open region.

18. The imaging apparatus according to claim 1, wherein the electrode connecting the second electrode and the pad includes a guard ring.

19. An electronic device comprising: a semiconductor substrate on which a photoelectric conversion unit is provided for each pixel; a first electrode provided in a trench separating the pixels in the semiconductor substrate; a second electrode provided on the light incident surface side of the semiconductor substrate; a pad to which a terminal for applying a voltage is connected, wherein the second electrode is connected to the first electrode and extends to the pad; and a processing unit for processing signals from the imaging device.

Images