Image sensor

Abstract

This imaging element comprises: a semiconductor substrate having one surface that serves as a light-incident surface; and another surface facing the one surface; and an imaging unit provided on the semiconductor substrate and having a plurality of sensor pixels that perform photoelectric conversion; and a power generation unit provided around the imaging unit on the semiconductor substrate and performing photoelectric conversion.

Description

Technical Field

[0001] The present disclosure relates to an image sensor having an imaging unit and a power generation unit.

Background Art

[0002] As a technology for the Internet of Things (IoT), a battery - less battery - driven technology is required. For example, Patent Document 1 discloses a solid - state image sensor in which a solar cell that receives light captured from an imaging lens is provided between a plurality of arranged light - receiving cells.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

[0004] By the way, in the image sensor provided with a solar cell as described above, it is required to achieve both excellent pixel characteristics and a high power generation amount.

[0005]

[0006] An image sensor according to an embodiment of the present disclosure The first includes a semiconductor substrate having one surface and the other surface facing each other, an imaging unit provided on the semiconductor substrate and having a plurality of sensor pixels that perform photoelectric conversion, a power generation unit provided around the imaging unit of the semiconductor substrate and extending to the other surface side of the imaging unit to perform photoelectric conversion, and a separation unit formed from one surface of the semiconductor substrate toward the other surface and extending in the in - plane direction of the semiconductor substrate inside the semiconductor substrate to electrically separate the imaging unit and the power generation unit. is provided. The semiconductor substrate has a first conductivity type region forming a pn junction and a second conductivity type region provided within the first conductivity type region and having a conductivity type different from that of the first conductivity type region. In the imaging unit, the second conductivity type region is formed for each sensor pixel in the first conductivity type region extending over the entire surface. . The second image sensor according to an embodiment of the present disclosure includes a semiconductor substrate having one surface and the other surface facing each other, an imaging unit provided on the semiconductor substrate and having a plurality of sensor pixels that perform photoelectric conversion, and a power generation unit provided around the imaging unit of the semiconductor substrate and extending to the other surface side of the imaging unit to perform photoelectric conversion. A separation portion is formed from one surface of the semiconductor substrate toward the other surface and extends in the in-plane direction of the semiconductor substrate inside the semiconductor substrate to electrically separate the imaging unit and the power generation unit. The semiconductor substrate has a first conductivity type region forming a pn junction and a second conductivity type region provided in the first conductivity type region and having a conductivity type different from that of the first conductivity type region. In the power generation unit, the second conductivity type region is formed in a comb shape in the first conductivity type region extending over the entire surface, and the second conductivity type region has a planar shape. The third image sensor according to an embodiment of the present disclosure includes a semiconductor substrate having one surface and the other surface facing each other, an imaging unit provided on the semiconductor substrate and having a plurality of sensor pixels that perform photoelectric conversion, and a power generation unit provided around the imaging unit of the semiconductor substrate and extending to the other surface side of the imaging unit to perform photoelectric conversion. A separation portion is formed from one surface of the semiconductor substrate toward the other surface and extends in the in-plane direction of the semiconductor substrate inside the semiconductor substrate to electrically separate the imaging unit and the power generation unit. The semiconductor substrate has a first conductivity type region forming a pn junction and a second conductivity type region provided in the first conductivity type region and having a conductivity type different from that of the first conductivity type region. In the power generation unit, the second conductivity type region is formed in a dot shape in the first conductivity type region extending over the entire surface, and the second conductivity type region has a planar shape.The fourth image sensor according to an embodiment of the present disclosure includes a semiconductor substrate having one surface and the other surface facing each other, an imaging unit provided on the semiconductor substrate and having a plurality of sensor pixels that perform photoelectric conversion, and a power generation unit provided around the imaging unit of the semiconductor substrate and extending to the other surface side of the imaging unit to perform photoelectric conversion. A separation unit is formed from one surface of the semiconductor substrate toward the other surface and extends in the in-plane direction of the semiconductor substrate inside the semiconductor substrate to electrically separate the imaging unit and the power generation unit. The semiconductor substrate has a first conductivity type region that forms a pn junction and a second conductivity type region provided in the first conductivity type region and having a conductivity type different from that of the first conductivity type region. In the power generation unit, a plurality of second conductivity type regions extending in the in-plane direction of the semiconductor substrate are laminated with the first conductivity type region interposed therebetween. The fifth image sensor according to an embodiment of the present disclosure includes a semiconductor substrate having one surface and the other surface facing each other, an imaging unit provided on the semiconductor substrate and having a plurality of sensor pixels that perform photoelectric conversion, and a power generation unit provided around the imaging unit of the semiconductor substrate and extending to the other surface side of the imaging unit to perform photoelectric conversion. A separation unit is formed from one surface of the semiconductor substrate toward the other surface and extends in the in-plane direction of the semiconductor substrate inside the semiconductor substrate to electrically separate the imaging unit and the power generation unit. The semiconductor substrate has an uneven shape on one surface.

[0007] An image sensor according to an embodiment of the present disclosure The first to fifth In the imaging device, a power generation unit that performs photoelectric conversion is provided on a semiconductor substrate around an imaging unit having a plurality of sensor pixels, so that the number and area of the sensor pixels constituting the imaging unit are not reduced, and the power generation unit is arranged without increasing the area of the semiconductor substrate.

Brief Description of the Drawings

[0008]

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Mode for Carrying Out the Invention

[0009] Hereinafter, an embodiment of the present disclosure will be described in detail with reference to the drawings. The following description is a specific example of the present disclosure, and the present disclosure is not limited to the following aspects. Also, the present disclosure is not limited to the arrangement, dimensions, dimensional ratios, etc. of each component shown in each figure. The order of description is as follows. 1. First Embodiment (Example of an imaging device having a power generation unit around the imaging unit) 1-1. Configuration of the imaging device 1-2. Operation of the imaging device 1-3. Action and effect 2. Second Embodiment (Example in which the sensor pixels of the imaging unit and the solar cells of the power generation unit have the same structure) 3. Third Embodiment (Example in which the power generation unit consists of a multi-stage solar cell) 4. Modifications 4-1. Modification 1 (Another example of the shape of the photoelectric conversion unit constituting the solar cell) 4-2. Modification 2 (Example of a surface-irradiation type imaging device) 4-3. Modification 3 (Example in which the light incident surface of the semiconductor substrate has an uneven structure) 4-4. Modification 4 (Example in which the photoelectric conversion unit constituting the sensor pixel is provided outside the semiconductor substrate) 5. Application Examples 6. Practical Applications 7. Examples

[0010] <1. First Embodiment> FIG. 1 is a plan view schematically showing the schematic configuration of an imaging device (imaging device 1) according to the first embodiment of the present disclosure. FIG. 2 shows the stacked configuration of the imaging device shown in FIG. 1. FIG. 3 schematically shows an example of the cross-sectional configuration of the imaging device 1 taken along line I-I shown in FIG. 1, and FIG. 4 schematically shows a specific example of the planar configuration of line I-I shown in FIG. 1 and its vicinity, for example, an example in which four pixels P arranged in two rows and two columns supply one pixel circuit. The imaging device 1 of the present embodiment is a CCD image sensor or a CMOS image sensor having a battery-less battery driving technique, and has a configuration in which one or a plurality of solar cells C are provided around an imaging unit 110 having a plurality of sensor pixels (hereinafter simply referred to as pixels P).

[0011] (1-1. Configuration of the Imaging Device) The imaging device 1 includes, for example, two substrates (a first substrate 100 and a second substrate 200). The imaging device 1 is an imaging device having a three-dimensional structure formed by bonding the first substrate 100 and the second substrate 200 together. On the first substrate 100, for example, an imaging unit 110 and a power generation unit 120 are provided on a semiconductor substrate 10. On the second substrate 200, for example, a peripheral circuit 210, a column ADC 220, a control unit 230, etc. are provided as a logic circuit. The imaging device 1 is, for example, a back-illuminated imaging device. An optical system 310 described later is disposed above the imaging device 1, specifically, on the back side of the first substrate 100, and light is incident from the back side of the first substrate 100 through this optical system 310.

[0012] The imaging unit 110 and the power generation unit 120 will be described below. In the present embodiment, the case where electrons among pairs of electrons and holes generated by the photoelectric conversion unit are read out as signal charges (when an n-type semiconductor region (N-) is used as the photoelectric conversion unit) will be described. Also, in the drawings, “+(plus)” attached to “P” and “N” indicates that the impurity concentration of the p-type or n-type is higher than that of the surrounding p-type semiconductor region or n-type semiconductor region, and “-(minus)” indicates that the impurity concentration of the p-type or n-type is lower than that of the surrounding p-type semiconductor region or n-type semiconductor region.

[0013] The imaging unit 110 and the power generation unit 120 of the present embodiment are both provided, for example, within an image circle X as shown in FIG. 1, and the power generation unit 120 is provided around the imaging unit 110. Here, the “image circle” refers to a circular range in which light transmitted through the optical system 310 forms an image on the light incident surface of the imaging device 1 (specifically, the back surface (surface S2) of the semiconductor substrate 10). Note that the above “circular” includes a perfect circle and an ellipse. The imaging unit 110 and the power generation unit 120 are electrically separated by a separation unit 130.

[0014] (Imaging Unit) The imaging unit 110 detects light in a predetermined wavelength band and performs photoelectric conversion. A plurality of pixels P are two-dimensionally arranged. In the semiconductor substrate 10, a photodiode (PD) is embedded and formed as a photoelectric conversion unit 11 for each pixel P. On the surface (surface S1) of the semiconductor substrate 10, a floating diffusion FD is provided. In the vicinity of the surface S1 of the semiconductor substrate 10, various transistors constituting the pixel circuit are formed.

[0015] The semiconductor substrate 10 is, for example, a p-type silicon (Si) substrate with an impurity concentration of 1×10 14 / cm 2 or more and 1×10 20 / cm 2 or less, and has an n-type semiconductor region (N-) that constitutes a photodiode PD serving as the photoelectric conversion unit 11 in a predetermined region.

[0016] In the vicinity of the surface S1 of the semiconductor substrate 10, a transfer transistor TR that transfers the signal charges generated in the photoelectric conversion unit 11 as a pixel transistor to, for example, a vertical signal line Lsig (see FIG. 24) is provided. The signal charges may be either electrons or holes generated by photoelectric conversion. Here, the case where electrons are read out as the signal charges will be described as an example. In the vicinity of the surface S1 of the semiconductor substrate 10, together with the transfer transistor TR, for example, a reset transistor RST, an amplification transistor AMP, and a selection transistor SEL are provided. Such transistors are, for example, MOSEFTs (Metal Oxide Semiconductor Field Effect Transistors). For example, for each pixel P, or as shown in FIG. 4, for every four pixels P arranged in two rows and two columns, for example, the pixel circuit shown in FIG. 5 is configured. The pixel circuit may be a three-transistor configuration including, for example, a transfer transistor TR, a reset transistor RST, and an amplification transistor AMP, or a four-transistor configuration with a selection transistor SEL added thereto.

[0017] The photoelectric conversion unit 11 is a pn junction photodiode PD formed by embedding, for each pixel P, an n-type semiconductor region (N-), for example, in the semiconductor substrate 10. The photoelectric conversion unit 11 generates charges corresponding to the amount of incident light by photoelectric conversion based on the incident light, and accumulates the generated charges. In the photodiode PD, the cathode is electrically connected to the source of the transfer transistor TR, and the anode is electrically connected to the reference potential line (for example, ground GND).

[0018] The transfer transistor TR operates based on a transfer signal supplied from the control unit 230 at a predetermined timing via a transfer signal line, and is for transferring the signal charges accumulated in the photoelectric conversion unit 11 to the floating diffusion FD. In the transfer transistor TR, the drain is electrically connected to the floating diffusion FD, and the gate is electrically connected to the drive signal line.

[0019] The floating diffusion FD is an n-type diffusion layer region (N+) formed in the p-type semiconductor layer. The floating diffusion FD is a charge holding means for temporarily holding the charges transferred from the photodiode PD, and is a charge-voltage conversion means for generating a voltage corresponding to the amount of the charges.

[0020] The reset transistor RST operates based on a reset signal supplied from the control unit at a predetermined timing via a reset signal line, and discharges the charges accumulated in the floating diffusion FD. The gate of the reset transistor RST is connected to the reset signal line. The source / drain region of the reset transistor RST is composed of n-type semiconductor regions (N+) 12, 13 formed on the surface S1 of the semiconductor substrate 10. One of the source / drain regions (n-type semiconductor region (N+) 12) also serves as the floating diffusion FD, and the other (n-type semiconductor region (N+) 13) is connected to the power supply line VDD.

[0021] The amplifying transistor AMP amplifies the voltage between the source and drain using, as the gate signal, the voltage corresponding to the charge accumulated in the floating diffusion FD, and supplies it as a pixel signal (light reception signal) to the selection transistor SEL. The gate of the amplifying transistor AMP is connected to one of the source / drain regions (n-type semiconductor region (N+) 12; floating diffusion FD) of the reset transistor RST. Although not shown, the source / drain regions of the amplifying transistor AMP are constituted by n-type semiconductor regions (N+) formed on the surface S1 of the semiconductor substrate 10, similar to the source / drain regions of the reset transistor RST. One of the source / drain regions shares a region with the other source / drain region (n-type semiconductor region (N+) 13) of the reset transistor RST and is connected to the power supply line VDD.

[0022] The selection transistor SEL operates based on a selection signal supplied from the control unit at a predetermined timing via the selection signal line, and outputs the pixel signal supplied from the amplifying transistor AMP to the vertical signal line Lsig. The gate of the selection transistor SEL is connected to the selection signal line. Although not shown, the source / drain regions of the selection transistor SEL are constituted by n-type semiconductor regions (N+) formed on the surface S1 of the semiconductor substrate 10, similar to the source / drain regions of the reset transistor RST. One of the source / drain regions shares a region with the other source / drain region of the amplifying transistor AMP, and the other is connected to the data output line.

[0023] On the surface S1 of the semiconductor substrate 10, a p-type semiconductor region (P+) 14 is further provided as the anode of the photodiode PD, and this p-type semiconductor region (P+) 14 is connected to a fixed potential (for example, ground GND as a reference potential). On the semiconductor substrate 10, an element isolation part 15 is further provided between adjacent pixels P.

[0024] The element isolation part 15 is for electrically isolating between adjacent pixels P. The element isolation part 15 is, for example, a so-called STI (Shallow Trench Isolation) provided on the surface S1 of the semiconductor substrate 10, and is provided so as to surround the pixel P as shown in FIG. 4, for example. The element isolation part 15 can be formed using an oxide film such as silicon oxide (SiO 2 ), hafnium oxide (HfO 2 ), zirconium oxide (ZrO 2 ), aluminum oxide (Al 2 O 3 ), titanium oxide (TiO 2 ) and tantalum oxide (Ta 2 O 5 ).

[0025] Note that the element isolation part 15 may be formed by embedding a metal film such as tungsten (W) in the opening for forming the element isolation part 15 and forming the oxide film around it (that is, the side surface and the bottom surface of the metal film). Thereby, while electrically isolating between adjacent pixels P, obliquely incident light that may be incident from adjacent pixels P can be blocked by the metal film and optically isolated. Further, the element isolation part 15 may be a so-called DTI (Deep Trench Isolation) that penetrates between the surface S1 and the surface S2 of the semiconductor substrate 10, such as the separation part 130 described later.

[0026] (Power generation part) The power generation unit 120 is composed of one or more solar cells C provided around the imaging unit 110. The solar cell C is a pn junction type photodiode PD and has a photoelectric conversion unit 21 formed on the surface S1 of the semiconductor substrate 10 and composed of, for example, an n-type semiconductor region (N-). The power generation unit 120 further has an n-type semiconductor region (N+) 22 having a higher n-type impurity concentration than the n-type semiconductor region (N-) serving as the photoelectric conversion unit 21 and a p-type semiconductor region (P+) 23 on the surface S1 of the semiconductor substrate 10. The n-type semiconductor region (N+) 22 is formed within the n-type semiconductor region (N-) serving as the photoelectric conversion unit 21 and is connected to a reference potential (for example, ground GND). The p-type semiconductor region (P+) 23 is connected to the cathode (positive).

[0027] The solar cell C extracts a current in which the charge generated by the incident light flows in the forward direction. The output voltage of the solar cell C is determined from the relationship between the current and voltage flowing through the photodiode PD. The voltage generated in the pn junction varies depending on the flowing current. For example, in the case of a silicon substrate, the voltage (electromotive force) at which the photodiode PD turns on is around 0.5V. When charging a battery, for example, the n-type semiconductor region (N+) 22 is connected to the ground GND, the voltage of the p-type semiconductor region (P+) 23 is connected to a DC-DC conversion circuit, or the solar cells C are stacked vertically to increase the voltage. Therefore, a high voltage is generated in the p-type semiconductor region (P+) 23 and a low voltage is generated in the n-type semiconductor region (N+) 22.

[0028] Incidentally, the unused area of the semiconductor substrate 10 that forms the power generation unit 120 around the imaging unit 110 is limited by optical factors such as the misalignment of the image circle X and the circuit scale such as the peripheral circuit 210 formed on the second substrate 200. Generally, it is determined by optical factors. For example, in the image sensor 1 having a rectangular imaging unit 110, the four corners of the imaging unit 110 become critical regions in terms of the distance from the image circle X. For example, in the image sensor 1 shown in FIG. 1, since the distance from the outer edge of the imaging unit 110 to the image circle X is the smallest at the four corners of the imaging unit 110, the solar cells C near the four corners of the imaging unit 110 deviate from the image circle X and no longer contribute to power generation.

[0029] Therefore, in FIG. 1, an example is shown in which the power generation unit 120 is continuously provided around the imaging unit 110. However, the present invention is not limited to this. For example, as shown in FIGS. 6A and 6C, it may be formed only inside the image circle X irradiated with light. Further, in FIGS. 6A and 6B, the shape of the power generation unit 120 combined with rectangles is shown, but the shape of the power generation unit 120 is not limited to this. For example, as shown in FIG. 6C, trapezoidal power generation units 120 may be provided on each side of the imaging unit 110 having a rectangular shape, for example.

[0030] (Separation unit) As described above, the separation unit 130 is for electrically separating the imaging unit 110 and the power generation unit 120. For example, as shown in FIG. 1, it is formed so as to surround the imaging unit 110. The separation unit 130 can be formed, for example, by an n-type semiconductor region (N-) 31 that penetrates between the surface S1 and the surface S2 of the semiconductor substrate 10. An n-type semiconductor region (N+) 32 having an n-type impurity concentration higher than that of the n-type semiconductor region (N-) 31 is provided on the surface S1 of the n-type semiconductor region (N-) 31. This n-type semiconductor region (N+) 32 is connected to the power supply line VDD as a fixed potential.

[0031] When light is incident on the imaging device 1, the voltage of the p-region (semiconductor substrate 10) of the power generation unit 120 increases. In order to electrically isolate the p-region of the power generation unit 120 from the p-region of the imaging unit 110, it is desirable that the p-region of the power generation unit 120 and the n-region (n-type semiconductor region (N-) 31 constituting the separation unit 130) for separation have a sufficient reverse bias. In the present embodiment, since the power supply line VDD is connected to the n-type semiconductor region (N-) 31 via the n-type semiconductor region (N+) 32 as described above, the potential difference between the p-region of the power generation unit 120 and the n-region (n-type semiconductor region (N-) 31) for separation is such that the potential of the p-region of the power generation unit 120 << the potential of the n-type semiconductor region (N-) 31. Thereby, the p-region of the power generation unit 120 and the p-region of the imaging unit 110 are electrically separated.

[0032] In the present embodiment, an example in which the power supply line VDD is connected to the n-type semiconductor region (N+) 32 is shown, similar to the n-type semiconductor region (N+) 13 of the imaging unit 110. However, it is not limited to this as long as the voltage of the n-type semiconductor region (N-) 31 becomes equal to or higher than the electromotive force of the solar cell C. For example, in the case of a one-stage solar cell C as shown in FIG. 3, its electromotive force is about 0.5V. Therefore, a voltage higher than 0.5V may be applied to the n-type semiconductor region (N+) 32. For example, by applying a voltage of about 1V, the p-region of the power generation unit 120 and the p-region of the imaging unit 110 can be electrically separated.

[0033] Also, in FIG. 3, an example in which the separation unit 130 is formed by the n-type semiconductor region (N-) 31 penetrating between the surface S1 and the surface S2 of the semiconductor substrate 10 is shown, but it is not limited to this. For example, as shown in FIG. 7, the imaging unit 110 and the power generation unit 120 may be electrically separated by the n-type semiconductor region (N-) 31 that is formed from the surface S1 to the surface S2 of the semiconductor substrate 10 and extends in the in-plane direction inside the semiconductor substrate 10 toward the power generation unit 120 at a deep position (e.g., near the surface S2) of the semiconductor substrate 10.

[0034] In addition, since the separation unit 130 only needs to be able to electrically separate the imaging unit 110 and the power generation unit 120, for example, as shown in FIG. 8, it may be formed by an insulating film 33 that penetrates between the surface S1 and the surface S2 of the semiconductor substrate 10 as so-called DTI (Deep Trench Isolation). The insulating film 33 can be formed using, for example, the same material as the element isolation unit 15. Specifically, as the material of the insulating film 33, for example, silicon oxide (SiO 2 ), hafnium oxide (HfO 2 ), zirconium oxide (ZrO 2 ), aluminum oxide (Al 2 O 3 ), titanium oxide (TiO 2 ), and tantalum oxide (Ta 2 O 5 ) etc. can be mentioned.

[0035] In addition, when the separation unit 130 is formed in the n-type semiconductor region (N-) 31, there is a possibility that the parasitic bipolar transistor may operate, so it is preferable to provide the separation unit 130 and the photoelectric conversion unit 21 at positions that are sufficiently separated. When the separation unit 130 is formed of the insulating film 33, since a bipolar transistor cannot be formed, the photoelectric conversion unit 21 can be provided closer to the separation unit 130 compared to the case where the separation unit 130 is formed in the n-type semiconductor region (N-) 31.

[0036] In addition, in FIG. 4, an example is shown in which the element isolation unit 15 adjacent to the separation unit 130 of the imaging unit 110 is provided separately from the separation unit 130, but the separation unit 130 may also serve as the element isolation unit 15.

[0037] As described above, the basic configurations of the imaging unit 110, the power generation unit 120, and the separation unit 130 that constitute the image sensor 1 of the present embodiment have been described, but the image sensor 1 can also have the following configurations.

[0038] For example, as shown in FIG. 9A, the imaging device 1 may form an optical black (OPB) region 110A for outputting optical black serving as a reference for the black level on one side of an imaging unit 110 having a rectangular shape. Further, the imaging device 1 may, for example, provide a dummy pixel region 110B in which dummy pixels having the same configuration as each pixel P are formed over the entire periphery of the imaging unit 110. Furthermore, a contact region 110C may be provided around the imaging unit 110.

[0039] Note that the OPB region 110A may be formed, for example, over the entire periphery of the imaging unit 110 as shown in FIG. 9B, or may be formed on two adjacent sides as shown in FIG. 9C. Also, the dummy pixel region 110B does not necessarily have to be provided over the entire periphery of the imaging unit 110, and may be formed, for example, on only one side.

[0040] In FIG. 9A, an example is shown in which the contact region 110C is provided between the imaging unit 110 and the separation unit 130. However, for example, as shown in FIG. 10A, it may be provided between the separation unit 130 and the power generation unit 120. Alternatively, the contact region 110C may be provided in contact with the periphery of the power generation unit 120 as shown in FIG. 10B, or may be provided inside the power generation unit 120 as shown in FIG. 10C. Furthermore, in FIG. 9A, an example is shown in which the contact region 110C is formed on only two sides, but the contact region 110C may be formed on the four sides, i.e., the top, bottom, left, and right sides, of the imaging unit 110 having a rectangular shape.

[0041] Furthermore, the imaging device 1 may, for example, provide a color filter, a light-shielding film, and an on-chip lens on the back surface (surface S2) side of the semiconductor substrate 10.

[0042] The color filter can be formed over the entire surface of the semiconductor substrate 10. Note that, from the viewpoint of photoelectric conversion efficiency, white (W) is preferable for the color filter provided in the power generation unit 120. However, from the viewpoints of manufacturing cost and the like, similar to the imaging unit 110, any one of red (R), green (G), and blue (B) filters may be provided. In that case, it is preferable to use a green (G) filter with the highest sensitivity.

[0043] The light shielding film is formed, for example, between each pixel P of the imaging unit 110 in which a plurality of pixels P are two-dimensionally arranged and above the OPB region 110A and the dummy pixel region 110B formed at the periphery of the imaging unit 110.

[0044] The on-chip lens is for condensing the light incident from above onto the light receiving surfaces of the respective pixels P two-dimensionally arranged in the imaging unit 110. Therefore, the on-chip lens is not necessary for the power generation unit 120, the separation unit 130, etc. However, for example, for the purpose of maintaining the symmetry of the uppermost layer of the imaging device 1, it may be arranged over the entire front surface of the semiconductor substrate 10, similar to the color filter. Further, when an on-chip lens is provided in the power generation unit 120, pupil correction may be performed.

[0045] (1-2. Operation of the imaging device) In the imaging device 1 of the present embodiment, signal charges (here, electrons) are acquired from each pixel P as follows. When light is incident on the imaging device 1 via the optical system 310, in the imaging unit 110, the light passes through the on-chip lens, the color filter, etc. and is detected (absorbed) by the photoelectric conversion unit 11 in each pixel P, and the color light of red (R), green (G), or blue (B) is photoelectrically converted. A reverse bias is applied to each pixel P. As a result, among the electron-hole pairs generated in the photoelectric conversion unit 11, the electrons move to and are accumulated in the n-type semiconductor region (N-) constituting the photoelectric conversion unit 11, and the holes move to and are discharged from the p-type semiconductor region.

[0046] In the power generation unit 120, charges are generated in the photoelectric conversion unit 21 that constitutes the solar cell C by the light incident on the power generation unit 120 via the optical system 310. A forward bias is applied to the solar cell C, and an output current is extracted from the cathode (positive) connected to the p-type semiconductor region (P+) 23. The current extracted from the cathode (positive) is used for the operating current of the imaging unit 110 and, for example, charging a battery built in an electronic device having an imaging element 1 such as a camera 2 (see, for example, FIG. 25).

[0047] FIG. 11A shows the change over time in the daily power generation amount of the power generation unit 120, and FIG. 11B shows the change over time in the remaining amount of the battery in one day. The power generation unit 120 generates power by sunlight or the like outdoors during the day, supplies an operating current to the imaging unit 110, and the excess is charged to the battery. In a dark place such as at night, the battery current is used as the operating current. Indoors, in addition to sunlight, light such as fluorescent light is added.

[0048] Note that the change over time in the remaining amount of the battery shown in FIG. 11B is an example, and whether the remaining amount of the battery decreases continuously or stepwise differs between the case where the imaging unit 110 operates constantly and the case where it operates intermittently. However, when viewed on average, it has a similar shape.

[0049] (1-3. Action and effect) The imaging device 1 of the present embodiment is provided with a power generation unit 120 having one or a plurality of solar cells C around an imaging unit 110 having a plurality of pixels P. Thereby, the power generation unit 120 can be provided without reducing the number and area of the pixels P of the imaging unit 110 and without increasing the area of the semiconductor substrate 10 on which the imaging unit 110 is provided. This will be described below.

[0050] As described above, as a technology for IoT, a battery - free battery - driving technology is required, and as important technologies, there are power - reduction and energy - harvesting technologies. As an energy - harvesting technology for an image sensor, it mainly tends to be a method using external light. As a general technology, a method of preparing a solar cell separately from an imager and generating power is known. However, it is necessary to at least modify the pixels used in the imager, and there are concerns about deterioration of noise characteristics, saturation characteristics, etc.

[0051] On the other hand, in the present embodiment, for example, in an image pickup device having a three - dimensional structure in which a semiconductor substrate having a plurality of sensor pixels (hereinafter referred to as an upper chip) and a semiconductor substrate having a signal processing circuit for processing signals obtained by each sensor pixel (hereinafter referred to as a lower chip) are laminated on each other, a solar cell is arranged in the peripheral portion of the semiconductor substrate having the plurality of sensor pixels. Specifically, as described above, the image pickup device 1 of the present embodiment is provided with a power - generation unit 120 having one or a plurality of solar cells C around an imaging unit 110 having a plurality of pixels P. The imaging unit 110 and the power - generation unit 120 are provided within an image circle X formed by imaging of light transmitted through an optical system 310 arranged above the image pickup device 1 on the light incident surface of the image pickup device 1 (for example, the surface S2 of the semiconductor substrate 10). Further, a separation unit 130 is provided between the imaging unit 110 and the power - generation unit 120, and the imaging unit 110 and the power - generation unit 120 are electrically separated by the separation unit 130.

[0052] In the image pickup device having the three - dimensional structure as described above, the image circle formed by a lens that guides light from a subject to the image pickup device and forms an image on the light - receiving surface of the image pickup device is designed to be larger than the pixel array in which a plurality of sensor pixels are arranged, taking into account mechanical misalignment. Also, in order to suppress the influence of pads formed on the outer periphery of the chip and reflection of light from the chip edge, a certain distance is ensured from the pixel array to the outer periphery of the chip in the upper chip. For this reason, there is an unused area where light enters in the main periphery of the upper chip.

[0053] In this embodiment, a power generation unit 120 having a solar cell C is provided in an unused area of the upper chip (specifically, the semiconductor substrate 10 of the first substrate 100). Thereby, it is possible to realize an imaging device that achieves both excellent pixel characteristics and a high power generation amount without reducing the number and area of the pixels P of the imaging unit 110 and without increasing the area of the semiconductor substrate 10 on which the imaging unit 110 is provided.

[0054] Hereinafter, second and third embodiments of the present disclosure and modification examples (modification examples 1 to 4) will be described. Note that the same components as those in the first embodiment are denoted by the same reference numerals and the description thereof will be omitted.

[0055] <2. Second Embodiment> FIG. 12 shows an example of a cross-sectional configuration of an imaging device (imaging device 1A) according to the second embodiment of the present disclosure. Note that FIG. 12 corresponds to the cross-sectional configuration taken along line II in FIG. 1. The imaging device 1A is a CCD image sensor or a CMOS image sensor having a battery-less battery driving technique, similar to the imaging device 1 in the first embodiment. In this embodiment, the difference from the first embodiment is that the solar cell C constituting the power generation unit 420 has the same structure as a plurality of pixels P constituting the imaging unit 110.

[0056] As described above, the power generation unit 420 is constituted by solar cells C having the same structure as a plurality of pixels P constituting the imaging unit 110. Specifically, as shown in FIG. 13, the solar cells C provided in the power generation unit 420 have similar planar configurations to each other, and as shown in FIG. 14, for example, have the same circuit configuration as the equivalent circuit of the pixel P shown in FIG. 5.

[0057] Note that in FIG. 13, an example is shown in which the element isolation portions 15 and 45 adjacent to the separation portion 130 of the imaging unit 110 and the power generation unit 420 are provided separately from the separation portion 130, but the separation portion 130 may also serve as the adjacent element isolation portions 15 and 45.

[0058] In addition, in the power generation unit 420, since there is no need to prevent crosstalk between adjacent solar cells C, as shown in FIG. 15, the element isolation part 45 may be omitted. In the case where it is desired to maintain the contrast between the imaging unit 110 and the power generation unit 420 in terms of the manufacturing process, the element isolation part 45 may be provided as shown in FIG. 13. However, since the element isolation part 45 may cause the generation of dark current, it is preferable not to provide it.

[0059] As described above, in the imaging device 1A of the present embodiment, a power generation unit 120 having a solar cell C having the same structure as the pixel P constituting the imaging unit 110 is provided around the imaging unit 110 which is an unused area of the semiconductor substrate 10. Thereby, the same effects as those of the first embodiment can be obtained, and the manufacturing process can be simplified.

[0060] <3. Third Embodiment> FIG. 16 shows an example of a cross-sectional configuration of an imaging device (imaging device 1B) according to the third embodiment of the present disclosure. FIG. 17 schematically shows a specific example of a planar configuration of the imaging device 1B shown in FIG. 16. Note that FIG. 16 corresponds to the cross-sectional configuration taken along the line I-I shown in FIG. 1. The imaging device 1B is a CCD image sensor or a CMOS image sensor having a battery-less battery driving technique, similar to the imaging device 1 in the first embodiment. In the present embodiment, the solar cell C constituting the power generation unit 520 is a multi-stage type (two-stage type in FIG. 16), which is different from the first embodiment.

[0061] The power generation unit 520 is composed of a multi-stage solar cell in which solar cells C are formed, for example, in a double layer (solar cell C1, solar cell C2) around the imaging unit 110. In the multi-stage power generation unit 520 as shown in FIG. 16, for example, a separation unit 140 having a configuration similar to that of the separation unit 130 is provided between the solar cell C1 and the solar cell C2. Specifically, the separation unit 140 is composed of an n-type semiconductor region (N-) 34, and an n-type semiconductor region (N+) 35 having a higher n-type impurity concentration than the n-type semiconductor region (N-) 34 is provided on its surface (surface S1). The solar cell C1 and the solar cell C2 are cascode-connected, and the n-type semiconductor region (N+) 35 is connected to the power supply line VDD together with the p-type semiconductor region (P+) 23A of the solar cell C1 and the n-type semiconductor region (N+) 22B of the solar cell C2. At this time, a voltage equal to or higher than the maximum voltage generated in the power generation unit 520 is applied to the n-type semiconductor region (N+) 35.

[0062] As described above, in the imaging device 1B of the present embodiment, a power generation unit 120 composed of a multi-stage solar cell C is provided around the imaging unit 110, which is an unused region of the semiconductor substrate 10. Thereby, the same effect as that of the first embodiment can be obtained, and an effect that the power generation amount in the power generation unit 520 can be improved is achieved.

[0063] <4. Modification Example> (4-1. Modification Example 1) Figs. 18A to 18C show other examples of the planar shape of the photoelectric conversion unit 21 that constitutes the solar cell C of the power generation unit 120 of the image sensor 1 according to the first embodiment as a modification (Modification 1) of the present disclosure. The n-type semiconductor region (N-) that constitutes the photoelectric conversion unit 21 may be, for example, comb-shaped as shown in Fig. 18A, or may be formed in a dot shape as shown in Fig. 18B. When the n-type semiconductor region (N-) is comb-shaped, for example, the n-type semiconductor region (N-) extending in the Y-axis direction may be formed only on one side of the plurality of n-type semiconductor regions (N-) extending in the X-axis direction, or may be formed in the middle of the plurality of n-type semiconductor regions (N-) extending in the X-axis direction. When the n-type semiconductor region (N-) is dot-shaped, it may be arranged in a horizontal row as shown in Fig. 18B, or may be arranged alternately as shown in Fig. 18C. Further, the n-type semiconductor region (N-) that constitutes the photoelectric conversion unit 21 may have a configuration in which p-type semiconductor regions (P-) are laminated in between (n-type semiconductor regions (N-) 21a, 21b) in the film thickness direction (Z-axis direction) of the semiconductor substrate 10, as shown in Fig. 19, for example.

[0064] By configuring the photoelectric conversion unit 21 (n-type semiconductor region (N-)) that constitutes the solar cell C in the above-described shape, the junction area (pn junction area) between the n-type semiconductor region (N-) and the p-type semiconductor region (P-) is improved. As a result, it becomes possible to improve the power generation amount in the power generation unit 120.

[0065] (4-2. Modification 2) Fig. 20 shows, as a modification (Modification 2) of the present disclosure, the surface S2 of the semiconductor substrate 10 that serves as the light incident surface of the image sensor 1 according to the first embodiment having an uneven structure. By making the light incident surface have an uneven structure in this way, for example, the sensitivity to wavelengths in the near-infrared band is improved, and it becomes possible to improve the power generation efficiency in the power generation unit 120.

[0066] (4-3. Modification 3) FIG. 21 shows an example of the cross-sectional structure of the imaging device 1C according to a modified example (modified example 3) of the present disclosure. Note that FIG. 21 corresponds to the cross-sectional structure along line I-I shown in FIG. 1. The imaging device 1C of this modified example is a so-called surface-irradiation type imaging device in which the surface (surface S1) side of the semiconductor substrate 10 serves as the light-irradiation surface, and the power generation unit 620 extends over the entire back surface (surface S2) of the semiconductor substrate 10 and is partially stacked with the imaging unit 110, which is different from the first embodiment. Specifically, the photoelectric conversion unit 61 (n-type semiconductor region (N-)) constituting the solar cell C extends from the surface (surface S1) of the semiconductor substrate 10 to the vicinity of the back surface (surface S2) in the plane, which is different from the first embodiment. In the imaging device 1C of this modified example, in order to electrically separate the imaging unit 110 and the power generation unit 620, the separation unit 630 also extends in the in-plane direction from the surface S1 of the semiconductor substrate 10 into the semiconductor substrate 10.

[0067] In FIG. 21, an example is shown in which the photoelectric conversion unit 61 (n-type semiconductor region (N-)) constituting the solar cell C extends into the semiconductor substrate 10 near the back surface (surface S2). However, as shown in FIG. 22, the photoelectric conversion unit 61 (n-type semiconductor region (N-)) may extend facing the back surface (surface S2) of the semiconductor substrate 10.

[0068] When the imaging devices 1C shown in FIGS. 21 and 22 are used as a time-of-flight (ToF) type distance measurement image sensor, they can also be used as a back-irradiation type imaging device.

[0069] (4-4. Modified Example 4) FIG. 23 shows an example of the cross-sectional structure of the imaging device 1D according to a modified example (modified example 4) of the present disclosure. For example, the photoelectric conversion unit constituting the imaging unit 110 of the imaging device (for example, the imaging device 1) described in the first embodiment and the like does not necessarily have to be the photodiode PD provided on the semiconductor substrate 10. For example, as in the imaging device 1D shown in FIG. 23, it may be configured by an organic photoelectric conversion unit 70 including an organic photoelectric conversion layer 72 formed using an organic material.

[0070] The organic photoelectric conversion unit 70 has a structure in which, for example, a lower electrode 71, a photoelectric conversion layer 72, and an upper electrode 73 are laminated in this order, and is provided, for example, on the surface S1 side of the semiconductor substrate 10. The lower electrode 71 is formed by dividing each pixel P by a conductive film having light transmissivity such as ITO. The photoelectric conversion layer 72 is composed of, for example, a p-type semiconductor and an n-type semiconductor, and has a bulk heterojunction structure in the layer. The bulk heterojunction structure is a p / n junction surface formed by mixing a p-type semiconductor and an n-type semiconductor. The p-type semiconductor functions as a relatively electron donor (donor), and the n-type semiconductor functions as a relatively electron acceptor (acceptor). The photoelectric conversion layer 72 can be formed over the entire surface of the imaging unit 110, for example. The upper electrode 73 is made of a conductive film having light transmissivity, like the lower electrode 71. For example, like the lower electrode 71, it may be separately formed for each pixel, or like the photoelectric conversion layer 72, it may be formed as a common electrode for each pixel P.

[0071] Note that other layers may be provided between the lower electrode 71 and the photoelectric conversion layer 72, and between the photoelectric conversion layer 72 and the upper electrode 73.

[0072] In the organic photoelectric conversion unit 70, the light incident from the upper electrode 73 side is absorbed by the photoelectric conversion layer 72, and the excitons generated thereby move to the interface between the electron donor and the electron acceptor constituting the photoelectric conversion layer 72 and dissociate into electrons and holes. The charges (electrons and holes) generated here are transported to different electrodes by diffusion due to the concentration difference of carriers and the internal electric field due to the difference in work function between the anode and the cathode, and are detected as photocurrent. The charges transported to the lower electrode 71 are transferred and accumulated, for example, to the floating diffusion FD formed on the surface S1 of the semiconductor substrate 10 through the through electrode TSV.

[0073] Thus, the photoelectric conversion unit constituting the imaging unit 110 may be not only the photodiode PD formed on the semiconductor substrate 10, but also, for example, an organic photoelectric conversion unit 70 having an organic layer (photoelectric conversion layer 72) formed outside the semiconductor substrate 10 (for example, in the light incident direction) using an organic material.

[0074] Furthermore, the imaging unit 110 may be configured as a so-called vertical spectroscopy type imaging unit by, for example, providing two photoelectric conversion units (inorganic photoelectric conversion units) in the depth direction of the semiconductor substrate 10 and combining the organic photoelectric conversion unit 70. Thereby, in the imaging unit 110, it becomes possible to acquire a plurality of types of color signals in one pixel P without using a color filter. Also, in FIG. 23, an example in which the organic photoelectric conversion unit 70 is provided on the surface (surface S1) side of the semiconductor substrate 10 is shown. However, for example, by using a through via or the like that penetrates the semiconductor substrate 10, it can also be arranged on the back surface (surface S2) side of the semiconductor substrate 10.

[0075] <5. Application Example> (Application Example 1) FIG. 24 shows the overall configuration of the imaging device (for example, imaging device 1) described in the first embodiment or the like. The imaging device 1 is, for example, a CMOS image sensor, has an imaging unit 110 as an imaging area on the first substrate 100, and has a peripheral circuit 210 including, for example, a row scanning unit 211, a horizontal selection unit 213, a column scanning unit 214, and a system control unit 212 on the second substrate 200.

[0076] The imaging unit 110 has, for example, a plurality of unit pixels P (for example, corresponding to the imaging device 1) two-dimensionally arranged in a matrix. Pixel drive lines Lread (specifically, row selection lines and reset control lines) are wired for each pixel row in this unit pixel P, and vertical signal lines Lsig are wired for each pixel column. The pixel drive line Lread transmits a drive signal for signal readout from the pixel. One end of the pixel drive line Lread is connected to the output end corresponding to each row of the row scanning unit 211.

[0077] The row scanning unit 211 is composed of a shift register, an address decoder, etc., and is a pixel driving unit that drives each unit pixel P of the imaging unit 110, for example, in units of rows. Signals output from each unit pixel P of the pixel row selected and scanned by the row scanning unit 211 are supplied to the horizontal selection unit 213 through each of the vertical signal lines Lsig. The horizontal selection unit 213 is composed of an amplifier, a horizontal selection switch, etc. provided for each vertical signal line Lsig.

[0078] The column scanning unit 214 is composed of a shift register, an address decoder, etc., and drives the horizontal selection switches of the horizontal selection unit 213 in order while scanning them. By the selective scanning by this column scanning unit 214, the signals of each pixel transmitted through each of the vertical signal lines Lsig are sequentially output to the horizontal signal line 215 and transmitted to the second substrate 200 through the horizontal signal line 215.

[0079] The circuit portion composed of the row scanning unit 211, the horizontal selection unit 213, the column scanning unit 214, and the horizontal signal line 215 may be formed on the second substrate 200, or may be disposed in an external control IC. Further, those circuit portions may be formed on another substrate connected by a cable or the like.

[0080] The system control unit 212 receives a clock given from outside the first substrate 100, data for commanding an operation mode, etc., and outputs data such as internal information of the imaging device 1. The system control unit 212 further has a timing generator that generates various timing signals, and performs drive control of peripheral circuits such as the row scanning unit 211, the horizontal selection unit 213, and the column scanning unit 214 based on the various timing signals generated by the timing generator.

[0081] (Application Example 2) The above-described imaging device 1 (or imaging devices 1A to 1D) can be applied to, for example, all types of electronic devices equipped with an imaging function, such as a camera system like a digital still camera or a video camera, or a mobile phone having an imaging function. FIG. 25 shows a schematic configuration of a camera 2 as an example thereof. This camera 2 is, for example, a video camera capable of shooting still images or moving images, and includes an imaging device 1, an optical system (optical lens) 310, a shutter device 311, a drive unit 313 that drives the imaging device 1 and the shutter device 311, and a signal processing unit 312.

[0082] The optical system 310 guides image light (incident light) from a subject to the imaging unit 110 of the imaging device 1. This optical system 310 may be composed of a plurality of optical lenses. The shutter device 311 controls the light irradiation period and the light shielding period to the imaging device 1. The drive unit 313 controls the transfer operation of the imaging device 1 and the shutter operation of the shutter device 311. The signal processing unit 312 performs various signal processes on the signal output from the imaging device 1. The video signal Dout after signal processing is stored in a storage medium such as a memory or output to a monitor or the like.

[0083] <6. Application Examples> (Application Example to an In-Vivo Information Acquisition System) Furthermore, the technology according to the present disclosure (this technology) can be applied to various products. For example, the technology according to the present disclosure may be applied to an endoscopic surgery system.

[0084] FIG. 26 is a block diagram showing an example of a schematic configuration of a patient's in-vivo information acquisition system using a capsule endoscope to which the technology according to the present disclosure (this technology) can be applied.

[0085] The in-vivo information acquisition system 10001 is composed of a capsule endoscope 10100 and an external control device 10200.

[0086] The capsule endoscope 10100 is swallowed by a patient during an examination. The capsule endoscope 10100 has an imaging function and a wireless communication function. While moving inside organs such as the stomach and intestines by peristaltic movement or the like until it is naturally excreted from the patient, it sequentially captures images of the inside of the organ (hereinafter also referred to as in-vivo images) at predetermined intervals, and sequentially wirelessly transmits information about the in-vivo images to an external control device 10200 outside the body.

[0087] The external control device 10200 comprehensively controls the operation of the in-vivo information acquisition system 10001. Further, the external control device 10200 receives information about the in-vivo images transmitted from the capsule endoscope 10100, and generates image data for displaying the in-vivo images on a display device (not shown) based on the received information about the in-vivo images.

[0088] In the in-vivo information acquisition system 10001, in this way, in-vivo images capturing the state of the patient's body can be obtained at any time from when the capsule endoscope 10100 is swallowed until it is excreted.

[0089] The configurations and functions of the capsule endoscope 10100 and the external control device 10200 will be described in more detail.

[0090] The capsule endoscope 10100 has a capsule-shaped housing 10101, and a light source unit 10111, an imaging unit 10112, an image processing unit 10113, a wireless communication unit 10114, a power supply unit 10115, a power source unit 10116, and a control unit 10117 are housed in the housing 10101.

[0091] The light source unit 10111 is composed of a light source such as an LED (light emitting diode), and irradiates light onto the imaging field of view of the imaging unit 10112.

[0092] The imaging unit 10112 is composed of an imaging device and an optical system including a plurality of lenses provided in front of the imaging device. The reflected light of the light irradiated on the body tissue to be observed (hereinafter referred to as observation light) is condensed by the optical system and enters the imaging device. In the imaging unit 10112, in the imaging device, the incident observation light is photoelectrically converted, and an image signal corresponding to the observation light is generated. The image signal generated by the imaging unit 10112 is provided to the image processing unit 10113.

[0093] The image processing unit 10113 is composed of a processor such as a CPU (Central Processing Unit) or a GPU (Graphics Processing Unit), and performs various signal processes on the image signal generated by the imaging unit 10112. The image processing unit 10113 provides the image signal subjected to the signal process to the wireless communication unit 10114 as RAW data.

[0094] The wireless communication unit 10114 performs predetermined processes such as modulation processing on the image signal subjected to the signal process by the image processing unit 10113, and transmits the image signal to the external control device 10200 via the antenna 10114A. Further, the wireless communication unit 10114 receives a control signal related to the drive control of the capsule endoscope 10100 from the external control device 10200 via the antenna 10114A. The wireless communication unit 10114 provides the control signal received from the external control device 10200 to the control unit 10117.

[0095] The power supply unit 10115 is composed of a power receiving antenna coil, a power regeneration circuit that regenerates power from the current generated in the antenna coil, a boost circuit, and the like. In the power supply unit 10115, power is generated using the principle of so-called non-contact charging.

[0096] The power supply unit 10116 is composed of a secondary battery and stores the power generated by the power feeding unit 10115. In FIG. 26, in order to avoid complication of the drawing, illustration such as an arrow indicating the power supply destination from the power supply unit 10116 is omitted, but the power stored in the power supply unit 10116 is supplied to the light source unit 10111, the imaging unit 10112, the image processing unit 10113, the wireless communication unit 10114, and the control unit 10117 and can be used for driving these units.

[0097] The control unit 10117 is composed of a processor such as a CPU and appropriately controls the driving of the light source unit 10111, the imaging unit 10112, the image processing unit 10113, the wireless communication unit 10114, and the power feeding unit 10115 according to a control signal transmitted from the external control device 10200.

[0098] The external control device 10200 is composed of a processor such as a CPU or GPU, or a microcomputer or a control board in which a processor and a storage element such as a memory are mixed. The external control device 10200 controls the operation of the capsule endoscope 10100 by transmitting a control signal to the control unit 10117 of the capsule endoscope 10100 via the antenna 10200A. In the capsule endoscope 10100, for example, the light irradiation condition on the observation target in the light source unit 10111 can be changed by a control signal from the external control device 10200. Also, the imaging conditions (for example, the frame rate, exposure value, etc. in the imaging unit 10112) can be changed by a control signal from the external control device 10200. Further, the content of the processing in the image processing unit 10113 and the conditions under which the wireless communication unit 10114 transmits an image signal (for example, the transmission interval, the number of transmitted images, etc.) may be changed by a control signal from the external control device 10200.

[0099] In addition, the external control device 10200 performs various image processes on the image signal transmitted from the capsule endoscope 10100, and generates image data for displaying the captured in-vivo image on a display device. Examples of such image processes include various signal processes such as development processing (demosaicing processing), high-image-quality processing (band enhancement processing, super-resolution processing, NR (Noise reduction) processing, and / or hand shake correction processing, etc.), and / or enlargement processing (electronic zoom processing). The external control device 10200 controls the driving of the display device to display the captured in-vivo image based on the generated image data. Alternatively, the external control device 10200 may cause the generated image data to be recorded in a recording device (not shown) or printed and output by a printing device (not shown).

[0100] As described above, an example of an in-vivo information acquisition system to which the technology according to the present disclosure can be applied has been described. The technology according to the present disclosure can be applied to, for example, the imaging unit 10112 among the configurations described above. Thereby, the detection accuracy is improved.

[0101] (Application Example to Endoscopic Surgery System) The technology (this technology) according to the present disclosure can be applied to various products. For example, the technology according to the present disclosure may be applied to an endoscopic surgery system.

[0102] FIG. 27 is a diagram showing an example of a schematic configuration of an endoscopic surgery system to which the technology (this technology) according to the present disclosure can be applied.

[0103] In FIG. 27, a state where a surgeon (doctor) 11131 is performing surgery on a patient 11132 on a patient bed 11133 using an endoscopic surgery system 11000 is illustrated. As shown, the endoscopic surgery system 11000 includes an endoscope 11100, other surgical instruments 11110 such as a pneumoperitoneum tube 11111 and an energy treatment instrument 11112, a support arm device 11120 that supports the endoscope 11100, and a cart 11200 on which various devices for endoscopic surgery are mounted.

[0104] The endoscope 11100 is composed of a lens barrel 11101 with a region of a predetermined length inserted into the body cavity of the patient 11132 from the tip, and a camera head 11102 connected to the proximal end of the lens barrel 11101. In the illustrated example, an endoscope 11100 configured as a so-called rigid endoscope having a rigid lens barrel 11101 is shown, but the endoscope 11100 may be configured as a so-called flexible endoscope having a flexible lens barrel.

[0105] An opening in which an objective lens is fitted is provided at the tip of the lens barrel 11101. A light source device 11203 is connected to the endoscope 11100, and the light generated by the light source device 11203 is guided to the tip of the lens barrel by a light guide extending inside the lens barrel 11101 and irradiated toward the observation target in the body cavity of the patient 11132 through the objective lens. Note that the endoscope 11100 may be a forward-viewing endoscope, a side-viewing endoscope, or a lateral-viewing endoscope.

[0106] An optical system and an imaging element are provided inside the camera head 11102, and the reflected light (observation light) from the observation target is condensed on the imaging element by the optical system. The observation light is photoelectrically converted by the imaging element, and an electrical signal corresponding to the observation light, that is, an image signal corresponding to the observation image, is generated. The image signal is transmitted as RAW data to a camera control unit (CCU) 11201.

[0107] The CCU 11201 is composed of a CPU (Central Processing Unit), a GPU (Graphics Processing Unit), etc., and comprehensively controls the operations of the endoscope 11100 and the display device 11202. Further, the CCU 11201 receives an image signal from the camera head 11102 and performs various image processes for displaying an image based on the image signal, such as development processing (demosaicing processing), on the image signal.

[0108] The display device 11202 displays an image based on an image signal that has been subjected to image processing by the CCU 11201 under the control of the CCU 11201.

[0109] The light source device 11203 is composed of a light source such as an LED (light emitting diode), etc., and supplies irradiation light for photographing the surgical site or the like to the endoscope 11100.

[0110] The input device 11204 is an input interface for the endoscopic surgery system 11000. The user can input various information and instruction inputs to the endoscopic surgery system 11000 via the input device 11204. For example, the user inputs an instruction to change the imaging conditions (type of irradiation light, magnification, focal length, etc.) by the endoscope 11100.

[0111] The treatment instrument control device 11205 controls the drive of the energy treatment instrument 11112 for cauterizing, incising tissues or sealing blood vessels, etc. The pneumoperitoneum device 11206 sends gas into the body cavity of the patient 11132 via the pneumoperitoneum tube 11111 in order to expand the body cavity of the patient for the purpose of securing the visual field by the endoscope 11100 and securing the working space for the surgeon. 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 forms such as text, image or graph, etc.

[0112] The light source device 11203 that supplies irradiation light for photographing the surgical site with the endoscope 11100 can be configured from, for example, an LED, a laser light source, or a white light source composed of a combination thereof. When a white light source is configured by a combination of RGB laser light sources, since the output intensity and output timing of each color (each wavelength) can be controlled with high precision, the white balance of the captured image can be adjusted in the light source device 11203. Further, in this case, the laser light from each of the RGB laser light sources is irradiated to the observation target in a time-division manner, and by controlling the driving of the imaging element of the camera head 11102 in synchronization with the irradiation timing, it is also possible to capture images corresponding to each of RGB in a time-division manner. According to this method, a color image can be obtained without providing a color filter on the imaging element.

[0113] Further, the driving of the light source device 11203 may be controlled so as to change the intensity of the output light at predetermined time intervals. By controlling the driving of the imaging element of the camera head 11102 in synchronization with the timing of the change in the intensity of the light and acquiring images in a time-division manner and synthesizing the images, it is possible to generate a high dynamic range image without so-called black crushing and white blooming.

[0114] In addition, 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 narrow-band light as compared with the irradiation light (i.e., white light) during normal observation, so-called narrow-band imaging for photographing a predetermined tissue such as blood vessels in the mucosal surface layer with high contrast is performed. Alternatively, in special light observation, fluorescence observation for obtaining an image by fluorescence generated by irradiating excitation light may be performed. In fluorescence observation, it is possible to irradiate the body tissue with excitation light and observe the fluorescence from the body tissue (autofluorescence observation), or to locally inject a reagent such as indocyanine green (ICG) into the body tissue and irradiate the body tissue with excitation light corresponding to the fluorescence wavelength of the reagent to obtain a fluorescence image. The light source device 11203 can be configured to supply such narrow-band light and / or excitation light corresponding to special light observation.

[0115] FIG. 28 is a block diagram showing an example of the functional configuration of the camera head 11102 and the CCU 11201 shown in FIG. 27.

[0116] 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 communicably connected to each other by a transmission cable 11400.

[0117] The lens unit 11401 is an optical system provided at a connection portion with the lens barrel 11101. Observation light taken in from the tip of the lens barrel 11101 is guided to the camera head 11102 and enters the lens unit 11401. The lens unit 11401 is configured by combining a plurality of lenses including a zoom lens and a focus lens.

[0118] The imaging device that constitutes the imaging unit 11402 may be one (so-called single-plate type) or multiple (so-called multi-plate type). When the imaging unit 11402 is configured as a multi-plate type, for example, image signals corresponding to RGB respectively may be generated by each imaging device, and a color image may be obtained by synthesizing them. Alternatively, the imaging unit 11402 may be configured to have a pair of imaging devices for respectively acquiring right-eye and left-eye image signals 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 site. When the imaging unit 11402 is configured as a multi-plate type, a plurality of lens units 11401 may be provided corresponding to each imaging device.

[0119] Also, the imaging unit 11402 does not necessarily have to be provided in the camera head 11102. For example, the imaging unit 11402 may be provided immediately behind the objective lens inside the lens barrel 11101.

[0120] The drive unit 11403 is constituted by an actuator, and under the control from the camera head control unit 11405, it moves the zoom lens and the focus lens of the lens unit 11401 along the optical axis by a predetermined distance. Thereby, the magnification and focus of the captured image by the imaging unit 11402 can be appropriately adjusted.

[0121] The communication unit 11404 is constituted by a communication device for transmitting and receiving various information to and from the CCU 11201. The communication unit 11404 transmits the image signal obtained from the imaging unit 11402 to the CCU 11201 via the transmission cable 11400 as RAW data.

[0122] In addition, the communication unit 11404 receives a control signal for controlling the drive of the camera head 11102 from the CCU 11201 and supplies it to the camera head control unit 11405. The control signal includes information related to imaging conditions, such as information specifying the frame rate of the captured image, information specifying the exposure value at the time of imaging, and / or information specifying the magnification and focus of the captured image.

[0123] Note that the imaging conditions such as the above frame rate, exposure value, magnification, and focus may be appropriately specified by the user, or may be automatically set by the control unit 11413 of the CCU 11201 based on the acquired image signal. In the latter case, so-called AE (Auto Exposure) function, AF (Auto Focus) function, and AWB (Auto White Balance) function are installed in the endoscope 11100.

[0124] The camera head control unit 11405 controls the drive of the camera head 11102 based on the control signal from the CCU 11201 received via the communication unit 11404.

[0125] The communication unit 11411 is composed of a communication device for transmitting and receiving various information to and from the camera head 11102. The communication unit 11411 receives the image signal transmitted from the camera head 11102 via the transmission cable 11400.

[0126] In addition, the communication unit 11411 transmits a control signal for controlling the drive of the camera head 11102 to the camera head 11102. The image signal and the control signal can be transmitted by telecommunication, optical communication, or the like.

[0127] The image processing unit 11412 performs various image processes on the image signal, which is RAW data transmitted from the camera head 11102.

[0128] The control unit 11413 performs various controls related to imaging of the surgical site and other areas by the endoscope 11100, and display of the captured images obtained by imaging the surgical site and other areas. For example, the control unit 11413 generates a control signal for controlling the drive of the camera head 11102.

[0129] Also, based on the image signal that has been subjected to image processing by the image processing unit 11412, the control unit 11413 causes the display device 11202 to display the captured image in which the surgical site and other areas are reflected. At this time, the control unit 11413 may recognize various objects in the captured image using various image recognition techniques. For example, the control unit 11413 can recognize surgical instruments such as forceps, specific biological sites, bleeding, mist during use of the energy treatment tool 11112, etc., by detecting the shape, color, etc. of the edges of the objects included in the captured image. When causing the display device 11202 to display the captured image, the control unit 11413 may use the recognition result to superimpose and display various surgical support information on the image of the surgical site. By superimposing and displaying 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 surely proceed with the surgery.

[0130] The transmission cable 11400 connecting the camera head 11102 and the CCU 11201 is an electrical signal cable corresponding to electrical signal communication, an optical fiber corresponding to optical communication, or a composite cable of these.

[0131] Here, in the illustrated example, communication is performed wired using the transmission cable 11400, but communication between the camera head 11102 and the CCU 11201 may be performed wirelessly.

[0132] As described above, an example of an endoscope surgical system to which the technology according to the present disclosure can be applied has been described. The technology according to the present disclosure can be applied to the imaging unit 11402 among the configurations described above. By applying the technology according to the present disclosure to the imaging unit 11402, the detection accuracy is improved.

[0133] Here, as an example, an endoscopic surgical system has been described. However, the technology according to the present disclosure may also be applied to other systems such as, for example, a microscopic surgical system.

[0134] (Application Example to a Moving Body) The technology according to the present disclosure can be applied to various products. For example, the technology according to the present disclosure may be realized as a device mounted on any type of moving body such as an automobile, an electric vehicle, a hybrid electric vehicle, a motorcycle, a bicycle, a personal mobility device, an airplane, a drone, a ship, a robot, a construction machine, an agricultural machine (tractor), etc.

[0135] FIG. 29 is a block diagram showing a schematic configuration example of a vehicle control system which is an example of a movement control system to which the technology according to the present disclosure can be applied.

[0136] The vehicle control system 12000 includes a plurality of electronic control units connected via a communication network 12001. In the example shown in FIG. 29, the vehicle control system 12000 includes a drive system control unit 12010, a body system control unit 12020, an out-vehicle information detection unit 12030, an in-vehicle information detection unit 12040, and an integrated control unit 12050. Further, as a functional configuration of the integrated control unit 12050, a microcomputer 12051, an audio / video output unit 12052, and an in-vehicle network I / F (interface) 12053 are shown.

[0137] The drive system control unit 12010 controls the operation of devices related to the drive system of the vehicle according to various programs. For example, the drive system control unit 12010 functions as a control device such as a driving force generation device for generating a driving force of the vehicle such as an internal combustion engine or a driving motor, a driving force transmission mechanism for transmitting the driving force to the wheels, a steering mechanism for adjusting the steering angle of the vehicle, and a braking device for generating a braking force of the vehicle.

[0138] The body control unit 12020 controls the operations of various devices installed in the vehicle according to various programs. For example, the body control unit 12020 functions as a control device for a keyless entry system, a smart key system, a power window device, or various lamps such as a headlamp, a backlamp, a brake lamp, a turn signal, or a fog lamp. In this case, radio waves transmitted from a portable device that substitutes for a key or signals from various switches can be input to the body control unit 12020. The body control unit 12020 receives these inputs of radio waves or signals and controls the vehicle's door lock device, power window device, lamps, etc.

[0139] The vehicle exterior information detection unit 12030 detects information outside the vehicle equipped with the vehicle control system 12000. For example, an imaging unit 11031 is connected to the vehicle exterior information detection unit 12030. The vehicle exterior information detection unit 12030 causes the imaging unit 11031 to capture an image outside the vehicle and receives the captured image. The vehicle exterior information detection unit 12030 may perform object detection processing or distance detection processing, such as for a person, a vehicle, an obstacle, a sign, or characters on the road surface, based on the received image.

[0140] The imaging unit 11031 is an optical sensor that receives light and outputs an electrical signal according to the amount of received light. The imaging unit 11031 can output the electrical signal as an image or as ranging information. Also, the light received by the imaging unit 11031 may be visible light or non-visible light such as infrared light.

[0141] The vehicle interior information detection unit 12040 detects information inside the vehicle. For example, a driver state detection unit 12041 that detects the state of the driver is connected to the vehicle interior information detection unit 12040. The driver state detection unit 12041 includes, for example, a camera that images the driver, and the vehicle interior information detection unit 12040 may calculate the degree of driver fatigue or concentration or determine whether the driver is dozing off based on the detection information input from the driver state detection unit 12041.

[0142] Based on the information inside and outside the vehicle acquired by the out-vehicle information detection unit 12030 or the in-vehicle information detection unit 12040, the microcomputer 12051 can calculate the control target values of the driving force generator, the steering mechanism, or the braking device, and output a control command to the drive system control unit 12010. For example, the microcomputer 12051 can perform cooperative control aimed at realizing functions of an ADAS (Advanced Driver Assistance System) including collision avoidance or shock mitigation of the vehicle, following driving based on the inter-vehicle distance, constant vehicle speed driving, collision warning of the vehicle, or lane departure warning of the vehicle.

[0143] In addition, based on the information around the vehicle acquired by the out-vehicle information detection unit 12030 or the in-vehicle information detection unit 12040, the microcomputer 12051 can perform cooperative control aimed at autonomous driving, etc., which runs autonomously regardless of the driver's operation, by controlling the driving force generator, the steering mechanism, or the braking device, etc.

[0144] Also, based on the out-vehicle information acquired by the out-vehicle information detection unit 12030, the microcomputer 12051 can output a control command to the body system control unit 12020. For example, the microcomputer 12051 can perform cooperative control aimed at anti-glare, such as controlling the headlamp according to the position of the preceding vehicle or the oncoming vehicle detected by the out-vehicle information detection unit 12030 and switching the high beam to the low beam.

[0145] The audio-visual output unit 12052 transmits at least one output signal of audio and image to an output device capable of notifying information visually or aurally to the vehicle occupants or outside the vehicle. In the example of FIG. 29, the output devices are exemplified by the audio speaker 12061, the display unit 12062, and the instrument panel 12063. The display unit 12062 may include, for example, at least one of an on-board display and a head-up display.

[0146] FIG. 30 is a diagram showing an example of the installation position of the imaging unit 11031.

[0147] In FIG. 30, the imaging unit 11031 includes imaging units 12101, 12102, 12103, 12104, and 12105.

[0148] The imaging units 12101, 12102, 12103, 12104, and 12105 are provided at positions such as the front nose, side mirrors, rear bumper, back door, and the upper part of the windshield inside the vehicle compartment of the vehicle 12100, for example. The imaging unit 12101 provided at the front nose and the imaging unit 12105 provided at the upper part of the windshield inside the vehicle compartment mainly acquire images in front of the vehicle 12100. The imaging units 12102 and 12103 provided at the side mirrors mainly acquire images on the sides of the vehicle 12100. The imaging unit 12104 provided at the rear bumper or the back door mainly acquires images behind the vehicle 12100. The imaging unit 12105 provided at the upper part of the windshield inside the vehicle compartment is mainly used for detecting a preceding vehicle or pedestrians, obstacles, traffic lights, traffic signs, or lanes.

[0149] Note that FIG. 30 shows an example of the imaging ranges of the imaging units 12101 to 12104. The imaging range 12111 indicates the imaging range of the imaging unit 12101 provided at the front nose, and the imaging ranges 12112 and 12113 indicate the imaging ranges of the imaging units 12102 and 12103 provided at the side mirrors, respectively. The imaging range 12114 indicates the imaging range of the imaging unit 12104 provided at the rear bumper or the back door. For example, by overlapping the image data captured by the imaging units 12101 to 12104, an overhead image of the vehicle 12100 as seen from above can be obtained.

[0150] At least one of the imaging units 12101 to 12104 may have a function of acquiring distance information. For example, at least one of the imaging units 12101 to 12104 may be a stereo camera including a plurality of imaging elements, or may be an imaging element having pixels for phase difference detection.

[0151] For example, based on the distance information obtained from the imaging units 12101 to 12104, the microcomputer 12051 determines the distance to each three-dimensional object within the imaging ranges 12111 to 12114 and the temporal change in this distance (relative speed with respect to the vehicle 12100). By doing so, it can extract, as the leading vehicle, the closest three-dimensional object on the traveling path of the vehicle 12100 that is traveling in substantially the same direction as the vehicle 12100 at a predetermined speed (e.g., 0 km / h or more). Further, the microcomputer 12051 can set the inter-vehicle distance to be secured in advance in front of the leading vehicle and perform automatic braking control (including follow-up stop control), automatic acceleration control (including follow-up start control), and the like. Thus, cooperative control can be performed for the purpose of autonomous driving, etc., without relying on the driver's operation.

[0152] For example, based on the distance information obtained from the imaging units 12101 to 12104, the microcomputer 12051 classifies and extracts three-dimensional object data regarding three-dimensional objects into motorcycles, ordinary vehicles, large vehicles, pedestrians, utility poles, and other three-dimensional objects, and can use it for automatic avoidance of obstacles. For example, the microcomputer 12051 discriminates between obstacles around the vehicle 12100 that are visible to the driver of the vehicle 12100 and those that are difficult to visually recognize. Then, the microcomputer 12051 determines the collision risk indicating the degree of danger of collision with each obstacle. When the collision risk is equal to or higher than a set value and there is a possibility of collision, it can output an alarm to the driver via the audio speaker 12061 or the display unit 12062, or perform forced deceleration or avoidance steering via the drive system control unit 12010 to provide driving support for collision avoidance.

[0153] At least one of the imaging units 12101 to 12104 may be an infrared camera that detects infrared rays. For example, the microcomputer 12051 can recognize a pedestrian by determining whether a pedestrian exists in the captured images of the imaging units 12101 to 12104. Such recognition of a pedestrian is performed, for example, by a procedure of extracting feature points in the captured images of the imaging units 12101 to 12104 as infrared cameras, and a procedure of performing pattern matching processing on a series of feature points indicating the outline of an object to determine whether it is a pedestrian. When the microcomputer 12051 determines that a pedestrian exists in the captured images of the imaging units 12101 to 12104 and recognizes the pedestrian, the audio-visual output unit 12052 controls the display unit 12062 to superimpose and display a rectangular outline for emphasizing the recognized pedestrian. Further, the audio-visual output unit 12052 may control the display unit 12062 to display an icon or the like indicating a pedestrian at a desired position.

[0154] <7. Embodiment> FIG. 31 shows a schematic configuration of an image sensor (image sensor 700) equipped with an energy harvesting function.

[0155] The image sensor 700 has, for example, an image pickup device 1, a DSP circuit 710, a communication unit 720, and a power control circuit 730.

[0156] The DSP circuit 710 is a signal processing circuit that processes signals supplied from the image pickup device 1. The DSP circuit 710 outputs, for example, image data obtained by processing signals from the image pickup device 1. The DSP circuit 710 may further be equipped with a neural network processing engine (NE). The DSP circuit 710 may further be connected to a position (GNSS) and a gyro sensor. Thereby, it becomes possible to perform detection and determination (metadata generation) of objects and situations such as the number of people, face recognition, and weather on the image acquired by the image pickup device 1 by the NE or the like.

[0157] The communication unit 720 transmits information externally using communication means such as 5G or LPWA (Low Power Wide Area) for the image data and metadata obtained in the DSP circuit 710.

[0158] The power control circuit 730 controls the power supply from, for example, a battery (not shown), and is connected to the imaging element 1, the DSP circuit 710, and the communication unit 720. Further, the power control circuit 730 may be configured to stably supply the power required for driving the imaging element 1 to the imaging element 1 by, for example, supplying the power generated in the power generation unit 120 of the imaging element 1.

[0159] As described above, the first to third embodiments, modification examples 1 to 4, application examples, and examples have been described. However, the present disclosure is not limited to the above embodiments and the like, and various modifications are possible. For example, it is not necessary to include all the components described in the above embodiments, and other components may be included.

[0160] Further, in FIG. 4 and the like, as a specific example of the pixel configuration of the imaging unit 110, a configuration of sharing 2×2 pixels is shown. However, the present disclosure is not limited to this, and for example, sharing 1×2 pixels or sharing 2×4 pixels may be used.

[0161] Note that the effects described here are not necessarily limited, and any effect described in the present disclosure may be used.

[0162] Note that the present disclosure may also have the following configuration. According to the present technology having the following configuration, an imaging element including a power generation unit can be configured without reducing the number and area of sensor pixels constituting the imaging unit, and without increasing the area of the semiconductor substrate. Therefore, it is possible to provide an imaging element that achieves both excellent pixel characteristics and a high power generation amount. (1) A semiconductor substrate having one surface and the other surface facing each other, An imaging unit provided on the semiconductor substrate and having a plurality of sensor pixels that perform photoelectric conversion, A power generation unit that is provided around the imaging unit of the semiconductor substrate and performs photoelectric conversion, and an image sensor including the same. (2) An optical system is disposed above the one surface of the semiconductor substrate, and the imaging unit and the power generation unit are disposed within an image circle of the optical system. The image sensor according to (1) above. (3) The image sensor according to (1) or (2) above, wherein the imaging unit and the power generation unit are electrically separated. (4) The semiconductor substrate further has a separation portion between the imaging unit and the power generation unit, and the imaging unit and the power generation unit are electrically separated by the separation portion. The image sensor according to any one of (1) to (3) above. (5) The image sensor according to (4) above, wherein the separation portion is formed of an insulating film or an impurity region. (6) The image sensor according to (4) or (5) above, wherein the separation portion penetrates between the one surface and the other surface of the semiconductor substrate. (7) The image sensor according to (4) or (5) above, wherein the separation portion is formed from the other surface of the semiconductor substrate toward the one surface and extends in the in-plane direction of the semiconductor substrate inside the semiconductor substrate. (8) A fixed potential is applied to the impurity region constituting the separation portion. The image sensor according to any one of (5) to (7) above. (9) The semiconductor substrate has a first conductivity type region that forms a pn junction and a second conductivity type region that is provided within the first conductivity type region and has a conductivity type different from that of the first conductivity type region. The image sensor according to any one of (1) to (8) above. (10) In the imaging unit, the second conductivity type region is formed for each sensor pixel in the first conductivity type region extending over the entire surface, the imaging device according to (9) above. (11) In the power generation unit, the second conductivity type region is formed in a serrated shape in the first conductivity type region extending over the entire surface, the imaging device according to (9) or (10) above. (12) In the power generation unit, the second conductivity type region is formed in a dot shape in the first conductivity type region extending over the entire surface, the imaging device according to (9) or (10) above. (13) In the power generation unit, a plurality of the second conductivity type regions extending in the in-plane direction of the semiconductor substrate are laminated with the first conductivity type region interposed therebetween, the imaging device according to any one of (9) to (12) above. (14) The power generation unit extends from the periphery of the imaging unit to the other surface of the semiconductor substrate and has a stacked structure with the imaging unit in part, the imaging device according to any one of (1) to (13) above. (15) The semiconductor substrate has an uneven shape on the one surface, the imaging device according to any one of (1) to (14) above. (16) The imaging unit has a substantially rectangular shape and has dummy pixels on at least one side of the periphery, the imaging device according to any one of (1) to (15) above. (17) The imaging unit further has an organic optoelectronic conversion unit containing an organic material outside the semiconductor substrate, the imaging device according to any one of (1) to (16) above.

[0163] This application claims priority based on U.S. Patent Application No. 62 / 907,170 filed on September 27, 2019 with the U.S. Patent and Trademark Office, and incorporates the entire contents of this application by reference into this application.

[0164] Those skilled in the art can conceive of various modifications, combinations, sub-combinations, and changes according to design requirements and other factors, and it is understood that they are included within the scope of the appended claims and their equivalents.

Claims

1. A semiconductor substrate having one opposing surface and another surface, An imaging unit provided on the semiconductor substrate and having a plurality of sensor pixels that perform photoelectric conversion, A power generation unit provided around the imaging unit of the semiconductor substrate and extending to the other surface side of the imaging unit, which performs photoelectric conversion, A separation unit that is formed from the one surface of the semiconductor substrate toward the other surface and extends in the in-plane direction of the semiconductor substrate inside the semiconductor substrate, and electrically separates between the imaging unit and the power generation unit, The semiconductor substrate has a first conductivity type region that forms a pn junction, and a second conductivity type region that is provided within the first conductivity type region and has a conductivity type different from that of the first conductivity type region, In the imaging unit, the second conductivity type region is formed for each sensor pixel in the first conductivity type region extending over the entire surface, An imaging device.

2. An optical system is disposed above the one surface of the semiconductor substrate, The imaging unit and the power generation unit are disposed within an image circle of the optical system. The imaging device according to claim 1.

3. The power generation unit has one or more solar cells, The photoelectric conversion unit constituting the one or more solar cells is formed from the one surface of the semiconductor substrate toward the other surface and extends in the in-plane direction of the semiconductor substrate inside the semiconductor substrate. The imaging device according to claim 1.

4. In the power generation unit, the second conductivity type region is formed in a comb shape in the first conductivity type region extending over the entire surface, The imaging device according to claim 1, wherein the second conductivity type region has a planar shape.

5. In the power generation unit, the second conductivity type region is formed in a dot shape in the first conductivity type region extending over the entire surface, The imaging device according to claim 1, wherein the second conductivity type region has a planar shape.

6. In the power generation unit, a plurality of the second conductivity type regions extending in the in-plane direction of the semiconductor substrate are laminated with the first conductivity type region in between. The imaging device according to claim 1.

7. The semiconductor substrate has an uneven shape on the one surface. The imaging device according to claim 1.

8. The imaging unit has a substantially rectangular shape and has dummy pixels on at least one side of the periphery. The imaging device according to claim 1.

9. The imaging unit further has an organic photoelectric conversion unit containing an organic material outside the semiconductor substrate. The imaging device according to claim 1.

10. A semiconductor substrate having one opposing surface and another surface, an imaging unit provided on the semiconductor substrate and having a plurality of sensor pixels that perform photoelectric conversion, a power generation unit provided around the imaging unit of the semiconductor substrate and extending to the other surface side of the imaging unit, which performs photoelectric conversion, a separation unit formed from the one surface of the semiconductor substrate toward the other surface, extending in the in-plane direction of the semiconductor substrate inside the semiconductor substrate, and electrically separating between the imaging unit and the power generation unit, the semiconductor substrate having a first conductivity type region forming a pn junction and a second conductivity type region provided within the first conductivity type region and having a conductivity type different from that of the first conductivity type region, in the power generation unit, the second conductivity type region is formed in a comb shape in the first conductivity type region extending over the entire surface, the second conductivity type region has a planar shape imaging device.

11. A semiconductor substrate having one opposing surface and another surface, an imaging unit provided on the semiconductor substrate and having a plurality of sensor pixels that perform photoelectric conversion, a power generation unit provided around the imaging unit of the semiconductor substrate and extending to the other surface side of the imaging unit, which performs photoelectric conversion, a separation unit formed from the one surface of the semiconductor substrate toward the other surface, extending in the in-plane direction of the semiconductor substrate inside the semiconductor substrate, and electrically separating between the imaging unit and the power generation unit, the semiconductor substrate having a first conductivity type region forming a pn junction and a second conductivity type region provided within the first conductivity type region and having a conductivity type different from that of the first conductivity type region, in the power generation unit, the second conductivity type region is formed in a dot shape in the first conductivity type region extending over the entire surface, the second conductivity type region has a planar shape imaging device.

12. A semiconductor substrate having one opposing surface and another surface, an imaging unit provided on the semiconductor substrate and having a plurality of sensor pixels that perform photoelectric conversion, a power generation unit provided around the imaging unit of the semiconductor substrate and extending to the other surface side of the imaging unit, which performs photoelectric conversion, a separation unit formed from the one surface of the semiconductor substrate toward the other surface, extending in the in-plane direction of the semiconductor substrate inside the semiconductor substrate, and electrically separating between the imaging unit and the power generation unit, The semiconductor substrate has a first conductivity type region forming a pn junction and a second conductivity type region provided in the first conductivity type region and having a conductivity type different from that of the first conductivity type region. In the power generation unit, a plurality of the second conductivity type regions extending in the in-plane direction of the semiconductor substrate are laminated with the first conductivity type region interposed therebetween. Image sensor. **Claim 13**: A semiconductor substrate having a first surface and a second surface facing each other, an imaging unit provided on the semiconductor substrate and having a plurality of sensor pixels that perform photoelectric conversion, a power generation unit provided around the imaging unit of the semiconductor substrate and extending to the second surface side of the imaging unit to perform photoelectric conversion, a separation unit formed from the first surface of the semiconductor substrate toward the second surface and extending in the in-plane direction of the semiconductor substrate inside the semiconductor substrate to electrically separate between the imaging unit and the power generation unit, and the semiconductor substrate has an uneven shape on the first surface. Image sensor.

Images