Solid-state imaging device and electronic apparatus

Abstract

A solid-state imaging device includes a semiconductor substrate, a photoelectric conversion section having a predetermined size in a thickness direction of the semiconductor substrate, a first charge accumulation section provided in the semiconductor substrate and accumulating signal charges generated by the photoelectric conversion section, and a transfer gate including a first electrode section embedded in the semiconductor substrate, having a first size in the thickness direction of the semiconductor substrate, and provided at the photoelectric conversion section side, and a second electrode section selectively provided at a position closer to the first charge accumulation section than the first electrode section and having a second size smaller than the first size in the thickness direction of the semiconductor substrate.

Description

[0001] Cross-references to related applications

[0002] This application claims the benefit of Japanese priority patent application JP 2019-135930, filed on July 24, 2019, the entire contents of which are incorporated herein by reference. Technical Field

[0003] This disclosure relates to a solid-state camera device including a semiconductor substrate and an electronic device including the solid-state camera device. Background Technology

[0004] Recently, the development of solid-state imaging devices, such as CMOS (complementary metal oxide semiconductor) camera sensors, has been progressing. These solid-state imaging devices use transmission gates to transfer the signal charge of photodiodes to floating diffusers.

[0005] For example, Patent Document 1 discloses a method for using a vertical gate electrode in a transmission gate. This vertical gate electrode is formed by embedding an electrode along the thickness direction of a semiconductor substrate.

[0006] List of cited references

[0007] Patent documents

[0008] [Patent Document 1] Japanese Unexamined Patent Application No. 2018-190797 Summary of the Invention

[0009] Technical issues

[0010] It is hoped that this solid-state camera device can suppress image quality degradation caused, for example, by signal charge remaining in the transmission path.

[0011] Therefore, there is a need to provide solid-state camera devices and electronic devices that can suppress image quality degradation.

[0012] Technical solutions to the problem

[0013] An imaging device according to an embodiment of the present disclosure includes a semiconductor substrate, a photoelectric conversion element in the semiconductor substrate, and a transmission transistor. The transmission transistor includes a transmission gate. The imaging device includes a charge accumulation portion in the semiconductor substrate. The transmission gate includes a vertical electrode extending from a first surface of the semiconductor substrate along a depth direction. The vertical electrode includes a first electrode portion embedded in the semiconductor substrate on the side of the photoelectric conversion element. The transmission gate includes a second electrode portion embedded in the semiconductor substrate on the side of the charge accumulation portion of the vertical electrode. The distal end of the first electrode portion extends from the first surface of the semiconductor substrate to a first distance. The distal end of the second electrode portion extends from the first surface of the semiconductor substrate to a second distance, and the first distance is greater than the second distance.

[0014] An electronic device according to an embodiment of the present disclosure includes an optical system and a camera device. The optical system forms an image on the camera device. The camera device includes a semiconductor substrate, a photoelectric conversion element in the semiconductor substrate, and a transmission transistor. The transmission transistor includes a transmission gate. The camera device includes a charge accumulation portion in the semiconductor substrate. The transmission gate includes a vertical electrode extending in a depth direction from a first surface of the semiconductor substrate, and the vertical electrode includes a first electrode portion embedded in the semiconductor substrate on the side of the photoelectric conversion element of the vertical electrode. The transmission gate includes a second electrode portion embedded in the semiconductor substrate on the side of the charge accumulation portion of the vertical electrode. The distal end of the first electrode portion extends from the first surface of the semiconductor substrate to a first distance. The distal end of the second electrode portion extends from the first surface of the semiconductor substrate to a second distance, and the first distance is greater than the second distance. The electronic device further includes a processing unit that processes image data output from the camera device.

[0015] In the solid-state imaging apparatus and electronic device according to embodiments of the present disclosure, the transmission gate includes a first electrode portion and a second electrode portion, wherein the dimension of the second electrode portion in the thickness direction of the semiconductor substrate is smaller than the dimension of the first electrode portion. Therefore, compared to the case where the transmission gate has a uniform dimension in the thickness direction of the semiconductor substrate, it is easier to adjust the modulation amount. Attached Figure Description

[0016] [ Figure 1 ] Figure 1 This is a schematic plan view of the overall structure of the camera device according to the first embodiment of the present disclosure.

[0017] [ Figure 2 ] Figure 2 yes Figure 1 A schematic plan view of the structure of a relevant part of the light receiving area shown.

[0018] [ Figure 3 ] Figure 3 It is shown Figure 2 A diagram showing an example of the circuit construction of the pixel.

[0019] [ Figure 4 ] Figure 4 It is along Figure 2 A schematic diagram illustrating an example of a cross-sectional structure cut by the IV-IV' line as seen in the image.

[0020] [ Figure 5 ] Figure 5 (A) is Figure 4 A plan view of one process of forming a vertical electrode, as shown. Figure 5 (B) is Figure 5 A cross-sectional view of the process shown in (A).

[0021] [ Figure 6 ] Figure 6 (A) is Figure 5 A floor plan of the subsequent process. Figure 6 (B) is Figure 6 A cross-sectional view of the process shown in (A).

[0022] [ Figure 7 ] Figure 7 (A) is Figure 6 A floor plan of the subsequent process. Figure 7 (B) is Figure 7 A cross-sectional view of the process shown in (A).

[0023] [ Figure 8 ] Figure 8 (A) is Figure 7 A floor plan of the subsequent process. Figure 8 (B) is Figure 8 The cross-sectional view shown in (A) is shown.

[0024] [ Figure 9 ] Figure 9 (A) is Figure 8 A floor plan of the subsequent process. Figure 9 (B) is Figure 9 The cross-sectional view shown in (A) is shown.

[0025] [ Figure 10 ] Figure 10 (A) is Figure 9 A floor plan of the subsequent process. Figure 10 (B) is Figure 10 The cross-sectional view shown in (A) is shown.

[0026] [ Figure 11 ] Figure 11 (A) is Figure 10A floor plan of the subsequent process. Figure 11 (B) is Figure 11 The cross-sectional view shown in (A) is shown.

[0027] [ Figure 12 ] Figure 12 This is a schematic diagram showing the cross-sectional structure of a relevant part of the camera device according to the comparative example.

[0028] [ Figure 13A ] Figure 13A It is shown by Figure 12 A diagram illustrating an example of the potential state caused by the transmission gate being turned on.

[0029] [ Figure 13B ] Figure 13B It is shown by Figure 12 A diagram illustrating an example of the potential state resulting from the transmission gate being turned off.

[0030] [ Figure 14 ] Figure 14 It is shown by Figure 4 A diagram illustrating an example of the potential state caused by the transmission gate being turned on.

[0031] [ Figure 15 ] Figure 15 It is used for explanation Figure 4 A schematic cross-sectional view illustrating the function and effect of the camera device.

[0032] [ Figure 16 ] Figure 16 This is a schematic cross-sectional view of the structure of a relevant part of the camera device according to Modified Example 1.

[0033] [ Figure 17 ] Figure 17 This is a schematic cross-sectional view of the structure of a relevant part of the camera device according to Modified Example 2.

[0034] [ Figure 18 ] Figure 18 This is a schematic cross-sectional view of the structure of a relevant part of the camera device according to Modified Example 3.

[0035] [ Figure 19 ] Figure 19 yes Figure 18 A schematic three-dimensional diagram showing the construction of the vertical electrode.

[0036] [ Figure 20 ] Figure 20 yes Figure 18 A schematic plan view of another example (1) of the construction of the vertical electrode shown.

[0037] [ Figure 21 ] Figure 21 yes Figure 18 A schematic plan view of another example (2) of the construction of the vertical electrode shown.

[0038] [ Figure 22 ] Figure 22 It is a schematic plan view of the structure of the relevant parts of the camera device according to Modification Example 4.

[0039] [ Figure 23A ] Figure 23A This is a schematic plan view of the structure of relevant parts of the camera device according to the second embodiment of the present disclosure.

[0040] [ Figure 23B ] Figure 23B It is along Figure 23A A schematic diagram of the cross-sectional structure cut by the B-B' line seen in the image.

[0041] [ Figure 24 ] Figure 24 (A) is Figure 23A and Figure 23B A plan view of one process of forming a vertical electrode, as shown. Figure 24 (B) is Figure 24 A cross-sectional view of the process shown in (A).

[0042] [ Figure 25 ] Figure 25 (A) is Figure 24 A floor plan of the subsequent process. Figure 25 (B) is Figure 25 A cross-sectional view of the process shown in (A).

[0043] [ Figure 26 ] Figure 26 (A) is Figure 25 A floor plan of the subsequent process. Figure 26 (B) is Figure 26 A cross-sectional view of the process shown in (A).

[0044] [ Figure 27 ] Figure 27 (A) is Figure 26 A floor plan of the subsequent process. Figure 27 (B) is Figure 27 A cross-sectional view of the process shown in (A).

[0045] [ Figure 28 ] Figure 28 This is a schematic cross-sectional view of the structure of a relevant part of the camera device according to Modification 5.

[0046] [ Figure 29A ] Figure 29AThis is a schematic plan view of the structure of relevant parts of the camera device according to the third embodiment of the present disclosure.

[0047] [ Figure 29B ] Figure 29B It is along Figure 29A A schematic diagram of the cross-sectional structure cut by the B-B' line seen in the image.

[0048] [ Figure 30 ] Figure 30 yes Figure 29B A schematic cross-sectional view of another example of the construction of the first and second vertical electrodes shown.

[0049] [ Figure 31 ] Figure 31 (A) is Figure 29A and Figure 29B A plan view of a process for forming the first and second vertical electrodes, as shown. Figure 31 (B) is Figure 31 A cross-sectional view of the process shown in (A).

[0050] [ Figure 32 ] Figure 32 (A) is Figure 31 A floor plan of the subsequent process. Figure 32 (B) is Figure 32 A cross-sectional view of the process shown in (A).

[0051] [ Figure 33 ] Figure 33 (A) is Figure 32 A floor plan of the subsequent process. Figure 33 (B) is Figure 33 A cross-sectional view of the process shown in (A).

[0052] [ Figure 34 ] Figure 34 (A) is Figure 33 A floor plan of the subsequent process. Figure 34 (B) is Figure 34 A cross-sectional view of the process shown in (A).

[0053] [ Figure 35A ] Figure 35A It is a schematic plan view of the structure of the relevant parts of the camera device according to Modification 6.

[0054] [ Figure 35B ] Figure 35B It is along Figure 35A A schematic diagram of the cross-sectional structure of the B-B' line as seen in the image.

[0055] [ Figure 36A ] Figure 36AIt is a schematic plan view of the structure of the relevant parts of the camera device according to Modification 7.

[0056] [ Figure 36B ] Figure 36B It is along Figure 36A A schematic diagram of the cross-sectional structure cut by the B-B' line seen in the image.

[0057] [ Figure 37A ] Figure 37A It is a schematic plan view of the structure of the relevant parts of the camera device according to Modification 8.

[0058] [ Figure 37B ] Figure 37B It is along Figure 37A A schematic diagram of the cross-sectional structure cut by the B-B' line seen in the image.

[0059] [ Figure 38 ] Figure 38 It is a schematic plan view of the structure of the relevant parts of the camera device according to Modification 9.

[0060] [ Figure 39A ] Figure 39A yes Figure 38 A schematic plan view of another example of the construction of the camera device shown.

[0061] [ Figure 39B ] Figure 39B It is along Figure 39A A schematic diagram of the cross-sectional structure cut by the B-B' line seen in the image.

[0062] [ Figure 40 ] Figure 40 It is a schematic plan view of the structure of the relevant parts of the camera device according to Modification 10.

[0063] [ Figure 41 ] Figure 41 It is shown Figure 40 A diagram illustrating an example of the construction of the equivalent circuit of the camera device.

[0064] [ Figure 42 ] Figure 42 This is a diagram illustrating an example of a schematic construction of a camera system including the camera device according to any of the first to third embodiments and their variations described above.

[0065] [ Figure 43 ] Figure 43 It is shown Figure 42 A diagram illustrating an example of the recording process of a camera system.

[0066] [ Figure 44 ] Figure 44 This is a block diagram illustrating an example of a schematic construction of a vehicle control system.

[0067] [ Figure 45 ] Figure 45 This diagram illustrates the installation locations of the vehicle exterior information detection unit and the camera unit.

[0068] [ Figure 46 ] Figure 46 This is a diagram illustrating an example of a schematic construction of an endoscopic surgical system.

[0069] [ Figure 47 ] Figure 47 This is a block diagram illustrating an example of the functional structure of a camera and a CCU (camera control unit). Detailed Implementation

[0070] Embodiments of this disclosure will now be described in detail with reference to the accompanying drawings. Note that the description will proceed in the following order.

[0071] 1. First embodiment (camera device having a transmission gate including a first electrode section and a second electrode section)

[0072] 2. Variation Example 1 (Example where the distal end of the vertical electrode is circular)

[0073] 3. Variation 2 (Example where a portion of the gate insulating film has a different thickness)

[0074] 4. Variation Example 3 (Example of a vertical electrode having a planar shape other than a circle)

[0075] 5. Variation Example 4 (Example of a planar electrode with a conical planar shape)

[0076] 6. Second embodiment (the camera device includes a transmission gate with a step between the first electrode section and the second electrode section)

[0077] 7. Modification 5 (Example of a third electrode portion provided between the second electrode portion and the first electrode portion)

[0078] 8. Third embodiment (camera device having a transmission gate including a first vertical electrode and a second vertical electrode)

[0079] 9. Modification 6 (Example with a third vertical electrode disposed between the first vertical electrode and the second vertical electrode)

[0080] 10. Variation 7 (Example of a planar electrode including a first planar electrode and a second planar electrode)

[0081] 11. Variation 8 (Example of a transmission gate including multiple vertical electrodes)

[0082] 12. Variation Example 9 (Example of a global shutter type camera device)

[0083] 13. Variation 10 (Example of multiple photodiodes sharing a floating diffuser)

[0084] 14. Applicable Examples

[0085] 15. Application Examples

[0086] <First Embodiment>

[0087] (Structure of camera device 1)

[0088] Figure 1 An example of the functional configuration of a solid-state imaging device (imaging device 1) according to a first embodiment of the present disclosure is schematically shown. The imaging device 1 is sensitive to light of wavelengths, for example, those in the visible region. For example, the imaging device 1 has a quadrilateral light-receiving region 10P and a peripheral region 10B located outside the light-receiving region 10P. Peripheral circuitry for driving the light-receiving region 10P is provided in the peripheral region 10B.

[0089] For example, in the light receiving area 10P of the imaging device 1, a plurality of pixels P arranged in a two-dimensional array are provided. The peripheral circuitry provided in the peripheral area 10B includes, for example, a row scanning unit 201, a horizontal selection unit 203, a column scanning unit 204, and a system control unit 202.

[0090] For example, for each pixel row, pixel P is provided with a pixel drive line Lread (e.g., a row selection line and a reset control line), and for each pixel column, pixel P is provided with a vertical signal line Lsig. The pixel drive line Lread transmits a drive signal for reading signals from each pixel P. One end of the pixel drive line Lread is connected to a corresponding output terminal of the row scanning unit 201 corresponding to each row.

[0091] The line scanning unit 201 includes a shift register, an address decoder, etc., and is, for example, a pixel driving unit that drives pixels P in the light receiving area 10P line by line. The signal output from each pixel P in the pixel row selectively scanned by the line scanning unit 201 is provided to the horizontal selection unit 203 through a corresponding vertical signal line Lsig. The horizontal selection unit 203 includes an amplifier and a horizontal selection switch provided for each vertical signal line Lsig.

[0092] The column scanning unit 204 includes a shift register, an address decoder, etc., and sequentially drives the horizontal selection switch of the horizontal selection unit 203 during scanning. This selective scanning by the column scanning unit 204 causes the signals from each pixel transmitted through each vertical signal line Lsig to be sequentially output to the horizontal signal line 205, and then input to a signal processing unit (not shown) through the horizontal signal line 205.

[0093] The system control unit 202 receives clock signals, data, and other information about the operation mode provided from the outside, and outputs data such as internal information about the camera device 1. The system control unit 202 also includes a timing generator that generates various timing signals, and drives and controls the row scanning unit 201, the horizontal selection unit 203, the column scanning unit 204, etc., based on the various timing signals generated by the timing generator.

[0094] Figure 2 It shows Figure 1 The schematic planar structure of the light receiving region 10P shown. Figure 2 A pixel P in the light receiving region 10P is shown. For example, multiple pixels P each include a photodiode (PD) 41, a transmission transistor TR, a floating diffuser (FD) 42, a reset transistor RST, and an amplifying transistor AMP. Here, PD 41 corresponds to a specific example of the "photoelectric conversion section" in this disclosure, and FD 42 corresponds to a specific example of the "first charge accumulation section" in this disclosure.

[0095] Figure 3 An example of the pixel circuit configuration of the imaging device 1 is shown. For example, PD 41 is electrically connected to the reset transistor RST, the amplification transistor AMP, and the selection transistor SEL via the transfer transistor TR and FD42. Such transistors include, for example, metal-oxide-semiconductor field-effect transistors (MOSFETs).

[0096] The cathode of PD 41 is electrically connected to the source of the transfer transistor TR, and the anode of PD 41 is electrically connected to a reference potential line (e.g., ground). The drain of the transfer transistor TR is electrically connected to FD 42. For example, the gate of the transfer transistor TR is electrically connected to the pixel drive line (…). Figure 1 (Pixel driving line Lread in the middle).

[0097] FD 42 is electrically connected to the source of the reset transistor RST and the gate of the amplifier transistor AMP. The drains of the reset transistor RST and the amplifier transistor AMP are connected to the power supply line VDD. The gate of the reset transistor RST is electrically connected to the pixel drive line. The source of the amplifier transistor AMP is electrically connected to the drain of the select transistor SEL. The source of the select transistor SEL is electrically connected to the vertical signal line (…). Figure 1 The vertical signal line (Lsig) in the selection transistor (SEL) is electrically connected to the pixel drive line.

[0098] When the transfer transistor TR is turned on, it transfers the signal charge from PD 41 to FD 42. The reset transistor RST resets the potential of FD 42 to a predetermined potential. When the reset transistor RST is turned on, it resets the potential of FD 42 to the potential of the power supply line VDD. The amplifying transistor AMP generates a signal as a pixel signal having a voltage corresponding to the charge level held in FD 42. The amplifying transistor AMP acts as a source follower amplifier and outputs a pixel signal having a voltage corresponding to the charge level generated by PD 41. The selection transistor SEL controls the output timing of the pixel signal from the amplifying transistor AMP. When the selection transistor SEL is turned on, the amplifying transistor AMP amplifies the potential of FD 42 and outputs a voltage corresponding to the amplified potential to the horizontal selection unit 203 via the vertical signal line.

[0099] Figure 4 It shows along Figure 2 The cross-sectional structure is taken from the IV-IV' line. The imaging device 1 includes a semiconductor substrate 11 having a front surface 11Sa and a back surface 11Sb that are opposite to each other. For example, the front surface 11Sa of the semiconductor substrate 11 is provided with a multilayer wiring layer (not shown), and the back surface 11Sb serves as a light receiving surface. For example, the imaging device 1 is a back-illuminated solid-state imaging device.

[0100] The semiconductor substrate 11 includes, for example, p-type silicon (Si). For each pixel P, a PD 41 is provided on the semiconductor substrate 11. The PD 41 is formed along the thickness direction of the semiconductor substrate 11. Figure 4 The PD 41 has a predetermined size starting from near the front surface 11Sa of the semiconductor substrate 11 in the Z-axis direction. PD 41 is, for example, an n-type impurity diffusion region. The PD 41 has a pn junction, wherein a p-well (not shown) is provided, for example, near the front surface 11Sa of the semiconductor substrate 11. That is, PD 41 is a so-called pn junction photodiode.

[0101] FD 42 is disposed, for example, near the front surface 11Sa of the semiconductor substrate 11. The signal charge generated by PD 41 is transferred to FD 42 via a transfer transistor TR. FD 42 is formed by diffusing a high concentration of n-type impurities, for example, in a p-well (not shown) disposed near the front surface 11Sa of the semiconductor substrate 11. That is, FD 42 is an n-type impurity diffusion region disposed near the front surface 11Sa of the semiconductor substrate 11. For example, compared to FD 42, PD 41 reaches a deeper level in the semiconductor substrate 11 (back side 11Sb side). In other words, the dimension of FD 42 in the thickness direction of the semiconductor substrate 11 is smaller than the dimension of PD 41 in the thickness direction of the semiconductor substrate 11.

[0102] The transfer transistor TR is provided between the PD 41 and the FD 42. The transfer transistor TR transfers the signal charge generated by the PD 41 to the FD 42. The transfer transistor TR includes, for example, a transfer gate TG and a gate insulating film 53. The transfer gate TG has, for example, a T-shaped cross-section. The transfer gate TG includes, for example, a vertical electrode 51 and a planar electrode 52. The transfer gate TG includes, for example, polycrystalline silicon (Poly-Si). Gate insulating films 53 are provided between the vertical electrode 51 and the planar electrode 52 and the semiconductor substrate 11, respectively. The gate insulating film 53 includes, for example, silicon oxide (SiO), etc.

[0103] The vertical electrode 51 is embedded inside the semiconductor substrate 11 from the front surface 11Sa and extends a predetermined length in the thickness direction of the semiconductor substrate 11. For example, the vertical electrode 51 extends substantially perpendicular to the front surface 11Sa. The transfer gate TG includes the vertical electrode 51, so that the signal charge of the PD 41 can be efficiently read from the PD 41 formed deeper in the semiconductor substrate 11. <00003​​​​​​​​​​​​The dimension of the vertical electrode 51 in the thickness direction of the semiconductor substrate 11 gradually decreases along the signal charge transport path from PD 41 to FD 42. For example, the first electrode portion 51a is disposed adjacent to PD 41 in the signal charge transport path from PD 41 to FD 42. For example, the dimension D1 of the first electrode portion 51a is the maximum dimension of the vertical electrode 51 in the thickness direction of the semiconductor substrate 11. For example, the second electrode portion 51b is disposed adjacent to FD 42 in the signal charge transport path from PD 41 to FD 42. For example, the dimension D2 of the second electrode portion 51b is the minimum dimension of the vertical electrode 51 in the thickness direction of the semiconductor substrate 11. This dimensional change from the first electrode portion 51a (dimension D1) to the second electrode portion 51b (dimension D2) results in the formation of an inclined surface Ss for the vertical electrode 51. This inclined surface Ss is the surface connecting the front end of the first electrode portion 51a and the front end of the second electrode portion 51b, and is the end face of the vertical electrode 51 embedded in the semiconductor substrate 11. The inclined surface Ss is inclined relative to the front surface 11Sa and the back surface 11Sb of the semiconductor substrate 11 (in the intersecting direction).

[0107] (Method for forming vertical electrode 51)

[0108] Next, we will refer to Figure 5 (A) and (B) to Figure 11 (A) and (B) illustrate the method of forming the vertical electrode 51. Figure 5 (A) to Figure 11 (A) shows the planar (XY plane) structure of the front 11Sa side of the semiconductor substrate 11. Figure 5 (B) to Figure 11 (B) shows the corresponding Figure 4 The cross-sectional structure.

[0109] First, such as Figure 5 As shown in (A) and (B), a silicon nitride film 12 and a silicon oxide film 13 are sequentially formed on the front surface 11Sa of the semiconductor substrate 11. Specifically, the formation of the silicon nitride film 12 and the silicon oxide film 13 is as follows: First, a silicon nitride film 12 is deposited on the entire front surface 11Sa of the semiconductor substrate 11. Then, the silicon nitride film 12 is patterned to form openings in the silicon nitride film 12 near the area where the vertical electrode 51 will be formed. Figure 7 The openings 12M in (A) and (B) are then formed. Subsequently, a silicon oxide film 13 is formed on the entire front surface 11Sa of the semiconductor substrate 11 to fill the openings in the silicon nitride film 12. Afterward, the silicon nitride film 12 and the silicon oxide film 13 are planarized. This removes the silicon oxide film 13 from the silicon nitride film 12 and forms a silicon oxide film 13 in the openings of the silicon nitride film 12.

[0110] After the silicon nitride film 12 and the silicon oxide film 13 are formed, as Figure 6 As shown in (A) and (B), a polycrystalline silicon film 14 with an opening 14M is formed. In the plan view, the opening 14M of the polycrystalline silicon film 14 is formed at a position overlapping the end of the region where the silicon oxide film 13 is formed. The opening 14M of the polycrystalline silicon film 14 is formed smaller than the region where the silicon oxide film 13 is formed.

[0111] Subsequently, as Figure 7 As shown in (A) and (B), the silicon oxide film 13 is etched using the opening 14M of the polysilicon film 14 through one-sided self-alignment. This allows the silicon oxide film 13 to be selectively retained at the end of the opening 12M of the silicon nitride film 12 to form a sloping surface of the silicon oxide film 13.

[0112] Subsequently, as Figure 8 As shown in (A) and (B), a polycrystalline silicon film 15 is formed on the entire front surface 11Sa of the semiconductor substrate 11. For example, the polycrystalline silicon film 15 is deposited along the inclined surface of the silicon oxide film 13.

[0113] Subsequently, as Figure 9 (A) and (B) to Figure 11 As shown in (A) and (B), a groove 11V is formed in the semiconductor substrate 11. For example, the groove 11V is formed by etching the semiconductor substrate 11, the polysilicon film 15, and the silicon oxide film 13. For example, this etching is performed under the condition that the etching rates of the polysilicon film 15, the semiconductor substrate 11, and the silicon oxide film 13 are substantially equal, and that the ratio of these etching rates to the etching rate of the silicon nitride film 12 is increased. This forms a groove 11V with a tilted surface. Subsequently, an insulating material and a conductive material are sequentially embedded in the groove 11V, thereby forming a gate insulating film 53 with a tilted surface Ss and a vertical electrode 51.

[0114] (Operation of camera device 1)

[0115] Such a camera device 1 acquires signal charge, for example, in the following manner. When light is incident on the back surface 11Sb of the semiconductor substrate 11, the light is detected (absorbed) by the PD 41 of each pixel P and photoelectric conversion is performed. For example, electrons in the electron-hole pairs generated by the PD 41 are accumulated in the FD 42, and holes are discharged into the power line VSS.

[0116] (The function and effect of camera device 1)

[0117] In the imaging device 1 according to the present embodiment, the vertical electrode 51 of the transfer gate TG includes a first electrode portion 51a having a size D1 on the PD 41 side and a second electrode portion 51b having a size D2 (D2 < D1) selectively provided at a position closer to the FD 42 than the first electrode portion 51a. Compared with the case where the transfer gate TG has a uniform size in the thickness direction of the semiconductor substrate 11, it is easier to adjust the modulation amount in this way. The operation and effects of the imaging device 1 will be described in detail below.

[0118] Figure 12 Fig. shows a cross-sectional structure of a relevant part of the light-receiving region of a solid-state imaging device (imaging device 1000) according to a comparative example. Figure 12 Corresponding to showing the imaging device 1 Figure 4 . Similar to the imaging device 1, the imaging device 1000 has a transfer gate TG including a vertical electrode 51 and a planar electrode 52 in each pixel. The difference between the imaging device 1000 and the imaging device 1 is that the vertical electrode 51 has a uniform size in the thickness direction of the semiconductor substrate 11. For example, in the imaging device 1000, the size of the vertical electrode 51 in the thickness direction of the semiconductor substrate 11 is the size D1 at any position in the signal charge transfer path from the PD 41 to the FD 42.

[0119] This kind of imaging device 1000 has a transfer gate TG including a vertical electrode 51 and can efficiently read the signal charge of the PD 41 formed deeper in the semiconductor substrate 11. However, if the vertical electrode 51 is designed to enable the signal charge to be completely transferred, the modulation amount near the vertical electrode 51 will increase, so potential drop is likely to occur. In addition, the increase in the modulation amount will result in the formation of a large number of transfer paths Path from the PD 41 to the FD 42.

[0120] Figure 13A and Figure 13B respectively show the potential states near the transfer gate TG. Figure 13A Fig. shows the potential state caused by the conduction of the gate voltage, Figure 13B Fig. shows the potential state caused by the cutoff of the gate voltage. As Figure 13AAs shown, the modulation section 51P increases with the conduction of the gate voltage, making it easier to generate a voltage drop in a portion (part B) of the vertical electrode 51. For example, part B is the distal portion of the vertical electrode 51 on the FD 42 side. However, the increase in the modulation section 51P results in the formation of a large number of transmission paths from PD 41 to FD 42. In the imaging device 1000, due to the generation of the potential drop in part B and the increase in the number of transmission paths, signal charge is likely to remain in the transmission paths. These signal charges remaining in the transmission paths may cause signal charge transmission failure due to charge extraction. For example, signal charge transmission failure caused by charge extraction can lead to image quality degradation, such as white spots.

[0121] Conversely, according to this embodiment, the size of the vertical electrode 51 gradually decreases along the signal charge transport path from PD41 to FD42 in the thickness direction of the semiconductor substrate 11. In other words, the size D2 of the second electrode portion 51b located adjacent to FD42 is smaller than the size D1 of the first electrode portion 51a located adjacent to PD41. Therefore, adjusting to the desired modulation amount becomes easier compared to the imaging device 1000.

[0122] Figure 14 The potential state near the transmission gate TG due to gate voltage turn-off is shown. As shown, by providing a smaller second electrode portion 51b at a position adjacent to FD 42, it is easier to adjust to the desired modulation amount near the vertical electrode 51. Specifically, with a vertical electrode 51 having a uniform size ( Figure 12 Compared to [previous version], this reduces the amount of modulation.

[0123] refer to Figure 15 The function and effect of the camera device 1 will be explained below. In the camera device 1, by adjusting the modulation amount to the desired value, the distal portion of the vertical electrode 51 can be effectively suppressed while maintaining the signal charge transmission capability. Figure 13A The potential drop in part B) is generated. Furthermore, compared to the imaging device 1000, the transmission path can be shortened and the increase in the number of transmission paths can be suppressed. Therefore, the signal charge retained in the transmission path is reduced. For this reason, transmission failures caused by charge extraction can be suppressed, thereby suppressing the degradation of image quality.

[0124] As described above, the transmission gate TG (more specifically, the vertical electrode 51) of the imaging device 1 according to this embodiment includes a first electrode portion 51a on the PD41 side and a second electrode portion 51b whose size in the thickness direction of the semiconductor substrate 11 is smaller than that of the first electrode portion 51a. Therefore, the signal charge retained in the transmission path can be reduced while maintaining the required modulation amount. Therefore, the degradation of image quality can be suppressed.

[0125] Furthermore, the first electrode portion 51a and the second electrode portion 51b are connected to each other via an inclined surface Ss. Therefore, this is different from the case where a step is provided between the first electrode portion 51a and the second electrode portion 51b (for example, as described later). Figure 23B Compared to the step (sd) in the previous method, it is easier to reduce the modulation amount. Therefore, the signal charge retained in the transmission path can be reduced more effectively.

[0126] The following will describe variations and other embodiments of the first embodiment described above. In the following description, components identical to those in the above embodiments are indicated by the same reference numerals, and their descriptions will be omitted as necessary.

[0127] <Variation Example 1>

[0128] Figure 16 The cross-sectional structure of the transmission gate TG of the imaging device 1 according to the modified example 1 of the first embodiment described above is schematically shown. The distal end of the vertical electrode 51 of the transmission gate TG has a rounded corner portion CP. Apart from this, the structure of the imaging device 1 according to the modified example 1 is the same as that of the imaging device 1 according to the first embodiment described above, and its function and effect are also the same.

[0129] For example, the distal end of the first electrode portion 51a has a corner portion CP. For example, the corner portion CP has a curved surface and is rounded. Near this rounded corner portion CP, a gate insulating film 53 is uniformly deposited compared to the sharp corner portion CP. Figure 4 Therefore, the electric field concentration caused by the reduced thickness of the gate insulating film 53 near the corner CP is reduced, thereby suppressing the degradation of image quality (e.g., white spots). The far corner of the second electrode portion 51b may be rounded.

[0130] <Variation Example 2>

[0131] Figure 17 The cross-sectional structures of the transmission gate TG and the gate insulating film 53 of the imaging device 1 according to the modified example 2 of the first embodiment described above are schematically shown. Here, the gate insulating film 53 (which is disposed between the vertical electrode 51 and the semiconductor substrate 11) Figure 4The thickness of a portion of the gate insulating film 53 (thickness t2, described later) is greater than the thickness of the remaining portion (thickness t1, described later). Furthermore, the imaging device 1 according to Modified Example 2 has the same structure as the imaging device 1 according to the first embodiment described above, and its function and effect are also the same.

[0132] For example, the thickness (thickness t2) of the gate insulating film 53 covering the corner CP at the far end of the vertical electrode 51 (more specifically, the first electrode portion 51a) is greater than the thickness (thickness t1) of the gate insulating film 53 covering the other portions of the vertical electrode 51 (t2>t1). This increase in the thickness of the gate insulating film 53 covering the corner CP results in the formation of a signal charge transport path that bypasses the corner CP. As described in Modification 1, electric field concentration tends to occur at the corner CP. If a signal charge transport path is formed through the corner CP, the transport efficiency will decrease. Therefore, by increasing the thickness of the gate insulating film 53 covering the corner CP, a signal charge transport path that bypasses the corner CP can be formed, thereby improving the transport efficiency. The thickness of the gate insulating film 53 covering the vertical electrode 51 other than the corner CP can be increased to be greater than the thickness of the rest of the gate insulating film 53.

[0133] <Variation Example 3>

[0134] Figure 18 The planar structure of a relevant part of the camera device 1 according to the modified example 3 of the first embodiment described above is schematically shown. Figure 18 The planar structure of the relevant portion of each pixel P of the imaging device 1 is shown. In this imaging device 1, the vertical electrode 51 of the transmission gate TG has a planar shape other than a circle. Furthermore, the structure of the imaging device 1 according to Modification 3 is the same as that of the imaging device 1 according to the first embodiment described above, and its function and effect are also the same.

[0135] For example, the vertical electrode 51 has a generally triangular planar shape. For instance, the vertical electrode 51 (transmission gate TG) is positioned between PD 41 and FD 42 such that the sides and vertices of the triangle are adjacent to PD 41 and FD 42, respectively. That is, the planar shape of the vertical electrode 51 gradually narrows along the signal charge transfer path from PD 41 to FD 42. Therefore, the signal charge transfer path around the vertical electrode 51 is formed to extend towards FD 42 on the PD 41 side. Thus, compared to the case where the vertical electrode 51 has a circular planar shape, the signal charge transfer path from PD 41 to FD 42 is shortened, and the probability of signal charge trapping in the transmission path is reduced. Therefore, the signal charge transfer efficiency from PD 41 to FD 42 can be improved, thereby improving image quality.

[0136] Figure 19 yes Figure 18 The diagram shows a schematic perspective view of the structure of the vertical electrode 51. For example, the vertical electrode 51 has a generally triangular prism shape. The first electrode portion 51a includes, for example, the side surface of the triangular prism, and the second electrode portion 51b includes, for example, the side edge of the triangular prism. An inclined surface Ss connecting the first electrode portion 51a and the second electrode portion 51b is provided in a bottom surface of the triangular prism.

[0137] Figure 20 and Figure 21 They are shown respectively Figure 18 Another example of the planar construction of the imaging device 1 (pixel P) shown. The vertical electrode 51 may have a planar shape other than a triangle. For example, the vertical electrode 51 may have a semi-circular planar shape ( Figure 20 In this case, the side corresponding to the circular portion or diameter of the semicircle is set to be adjacent to PD 41. Therefore, the vertical electrode 51 has a shape that gradually narrows along the signal charge transport path from PD 41 to FD 42. For example, the vertical electrode 51 may have a polygonal planar shape. Figure 21 The polygonal shape can be a shape that gradually narrows along the signal charge transport path from PD 41 to FD 42. The vertices of the triangles or any other polygons included in the planar shape of the vertical electrode 51 can be circular.

[0138] <Variation Example 4>

[0139] Figure 22 The planar structure of a relevant part of the camera device 1 according to the modified example 4 of the first embodiment described above is schematically shown. Figure 22 The planar structure of the relevant portion of each pixel P of the imaging device 1 is shown. The planar electrode 52 of the transmission gate TG of the imaging device 1 has a planar shape other than a square or rectangle. Furthermore, the structure of the imaging device 1 according to Modification 4 is the same as that of the imaging device 1 according to the first embodiment described above, and its function and effect are also the same.

[0140] For example, the planar electrode 52 may have a generally trapezoidal planar shape. For instance, the planar electrode 52 (transmission gate TG) is positioned between PD 41 and FD 42 such that the lower and upper bases of the trapezoid are adjacent to PD 41 and FD 42, respectively. The length of the upper base is less than the length of the lower base. The planar shape of the planar electrode 52 will be described in detail below.

[0141] For example, a pair of sides of the planar electrode 52, which represents the signal charge transfer path from PD 41 to FD 42 and extends vertically relative to the virtual line VL, are referred to as sides 52da and 52db. Side 52da (lower base) is positioned adjacent to PD 41, and side 52db (upper base) is positioned adjacent to FD 42. The length of side 52db is less than the length of side 52da (side 52db < side 52da). That is, the planar electrode 52 has a shape that gradually narrows along the signal charge transfer path from PD 41 to FD 42. Therefore, directly below the planar electrode 52, the signal charge transfer path bypassing the vertical electrode 51 is formed to extend towards FD 42 on the PD 41 side in a manner that gradually concentrates towards FD 42. Therefore, compared to the case where the planar electrode 52 has a square or rectangular planar shape, the signal charge transfer path from PD 41 to FD 42 is shortened, and the probability of signal charge trapping in the transmission path is reduced. Therefore, the signal charge transfer efficiency from PD 41 to FD 42 can be improved, thereby improving image quality. The planar electrode 52 can have any conical planar shape other than a general trapezoid, and can have a planar shape such as a triangle, a semicircle, or a polygon. The vertices of the triangle or any other polygon that provides the planar shape of the planar electrode 52 can be circular.

[0142] <Second Embodiment>

[0143] Figure 23A and Figure 23B The structure of relevant parts of the camera device (camera device 2) according to the second embodiment of the present disclosure is shown respectively. Figure 23A The planar structure of the relevant portion of each pixel P of the imaging device 2 is shown. Figure 23B It shows along Figure 23A The cross-sectional structure seen in the image is taken by the B-B' line. Figure 23B Corresponding to the camera device 1 shown according to the first embodiment described above. Figure 4 The imaging device 2 has a step (step sd) disposed between the first electrode portion 51a and the second electrode portion 51b of the vertical electrode 51. Apart from this, the structure of the imaging device 2 is the same as that of the imaging device 1 according to the first embodiment described above, and its function and effect are also the same.

[0144] The dimension of the vertical electrode 51 in the thickness direction of the semiconductor substrate 11 decreases in a stepwise manner along the signal charge transport path from PD 41 to FD 42. For example, the first electrode portion 51a is disposed adjacent to PD 41 in the signal charge transport path from PD 41 to FD 42 and has a predetermined thickness along the transport path. For example, the second electrode portion 51b is disposed adjacent to FD 42 in the signal charge transport path from PD 41 to FD 42 and has a predetermined thickness along the transport path. This dimensional change from the first electrode portion 51a (dimension D1) to the second electrode portion 51b (dimension D2) results in the formation of a step sd of the vertical electrode 51 in the thickness direction of the semiconductor substrate 11. This step sd is disposed between the distal end of the first electrode portion 51a and the distal end of the second electrode portion 51b.

[0145] The aforementioned variations 1 to 4 also apply to the imaging device 2. For example, the distal end of the vertical electrode 51 (first electrode portion 51a) of the imaging device 2 may have a rounded corner (see...). Figure 16 The thickness of a portion of the gate insulating film 53 may be greater than the thickness of other portions of the gate insulating film 53. Figure 17 The vertical electrode 51 may have a planar shape other than a circle (see...). Figure 18 , Figure 20 and Figure 21 The planar electrode 52 can have a planar shape other than a square or a rectangle (see...). Figure 22 ).

[0146] Next, we will refer to Figure 24 (A) and (B) to Figure 27 (A) and (B) illustrate the method for forming a vertical electrode 51 with a step sd. Figure 24 (A) to Figure 27 (A) shows the planar (XY plane) structure of the front 11Sa side of the semiconductor substrate 11. Figure 24 (B) to Figure 27 (B) shows the corresponding Figure 23B The cross-sectional structure.

[0147] First, such as Figure 24 As shown in (A) and (B), a resist film 21 with an opening 21M is formed on the front surface 11Sa of the semiconductor substrate 11. For example, the opening 21M has a semi-circular planar shape. The opening 21M is formed at a position in the planar view that overlaps with the area where the first electrode portion 51a will be formed. For example, the opening 21M is formed by photolithography.

[0148] Next, as Figure 25As shown in (A) and (B), the semiconductor substrate 11 is dry-etched through the opening 21M of the resist film 21. By doing so, a groove 11VA is formed on the portion of the semiconductor substrate 11 corresponding to the opening 21M.

[0149] Subsequently, as Figure 26 As shown in (A) and (B), the opening 21M of the resist film 21 is widened, for example, by photolithography. By doing so, the planar shape of the opening 21M changes from semi-circular to circular, for example.

[0150] Subsequently, as Figure 27 As shown in (A) and (B), the semiconductor substrate 11 is dry-etched through the opening 21M of the resist film 21. By doing so, a groove 11VB is formed on the semiconductor substrate 11 corresponding to the widened portion of the opening 21M, and the groove 11VA is made deeper. That is, the groove 11VA is formed deeper than the groove 11VB, resulting in a step between the grooves 11VA and 11VB. Subsequently, an insulating material and a conductive material are sequentially embedded in these grooves 11VA and 11VB. By doing so, a gate insulating film 53 and a first electrode portion 51a are formed in the groove 11VA, and a gate insulating film 53 and a second electrode portion 51b are formed in the groove 11VB.

[0151] Similar to the imaging device 1 according to the first embodiment described above, the imaging device 2 according to this embodiment has a transmission gate TG (more specifically, a vertical electrode 51) including a first electrode portion 51a and a second electrode portion 51b, wherein the size of the second electrode portion 51b is smaller than the size of the first electrode portion 51a in the thickness direction of the semiconductor substrate 11. Therefore, the signal charge retained in the transmission path can be reduced while maintaining the desired modulation amount. Thus, image quality degradation can be suppressed.

[0152] Furthermore, a single vertical electrode 51 includes a first electrode portion 51a and a second electrode portion 51b, and in the case where the first electrode portion 51a and the second electrode portion 51b are separate from each other and disposed among a plurality of vertical electrodes (see later description). Figure 29A and Figure 29B Compared to the first embodiment described above, it is easier to reduce the modulation amount. Therefore, the signal charge retained in the transmission path can be reduced more effectively. In addition, the vertical electrode 51 can be formed by simple photolithography and simple etching processes, making the manufacturing process easier than that of the vertical electrode 51 described in the first embodiment above.

[0153] <Variation Example 5>

[0154] Figure 28 The cross-sectional structure of a relevant part of the camera device 2 according to the modified example 5 of the second embodiment described above is schematically shown. Figure 28 Corresponding to the second embodiment described above Figure 23B The vertical electrode 51 of the imaging device 2 includes a third electrode portion 51c located between the first electrode portion 51a and the second electrode portion 51b. Apart from this, the structure of the imaging device 2 is the same as that of the imaging device 2 according to the second embodiment described above, and its function and effect are also the same.

[0155] The dimensions of the vertical electrode 51 in the thickness direction of the semiconductor substrate 11 decrease stepwise along the signal charge transport path from PD 41 to FD 42. For example, in the signal charge transport path from PD 41 to FD 42, a third electrode portion 51c is disposed between the first electrode portion 51a and the second electrode portion 51b. The third electrode portion 51c has a dimension D3 in the thickness direction of the semiconductor substrate 11. For example, this dimension D3 is smaller than the dimension D1 of the first electrode portion 51a and larger than the dimension D2 of the second electrode portion 51b (D1>D3>D2). The vertical electrode 51 has multiple steps (steps sda and sdb) in the thickness direction of the semiconductor substrate 11. The dimensional change from the first electrode portion 51a (dimension D1) to the third electrode portion 51c (dimension D3) results in the formation of step sda, and the dimensional change from the third electrode portion 51c (dimension D3) to the second electrode portion 51b (dimension D2) results in the formation of step sdb. Step sda is disposed between the distal end of the first electrode portion 51a and the distal end of the third electrode portion 51c, and step sdb is disposed between the distal end of the third electrode portion 51c and the distal end of the second electrode portion 51b. The third electrode portion 51c is disposed between the first electrode portion 51a and the second electrode portion 51b in this manner, making it easier to adjust the modulation amount. Two or more electrode portions of different sizes can be disposed between the first electrode portion 51a and the second electrode portion 51b.

[0156] <Third Embodiment>

[0157] Figure 29A and Figure 29B The structure of the relevant parts of the camera device (camera device 3) according to the third embodiment of the present disclosure is shown schematically. Figure 29A The planar structure of the relevant portion of each pixel P of the imaging device 3 is shown. Figure 29B It shows along Figure 29A The cross-sectional structure seen in the image is taken by the B-B' line. Figure 29B Corresponding to the camera device 1 shown in the first embodiment above Figure 4 The transmission gate TG of the camera device 3 includes a first vertical electrode 51A and a second vertical electrode 51B that are separated from each other. Apart from this, the camera device 3 has the same structure as the camera device 1 according to the first embodiment described above, and its function and effect are also the same.

[0158] A first vertical electrode 51A and a second vertical electrode 51B are sequentially disposed along the signal charge transport path from PD 41 to FD 42. For example, in the signal charge transport path from PD 41 to FD 42, the first vertical electrode 51A is disposed adjacent to PD 41. Here, the first vertical electrode 51A includes a first electrode portion 51a, and the first vertical electrode 51A has a dimension D1 in the thickness direction of the semiconductor substrate 11. For example, in the signal charge transport path from PD 41 to FD 42, the second vertical electrode 51B is disposed adjacent to FD 42. For example, a gate insulating film 53 is disposed between the second vertical electrode 51B and the first vertical electrode 51A, and the first vertical electrode 51A and the second vertical electrode 51B are separate. Here, the second vertical electrode 51B includes a second electrode portion 51b, and the second vertical electrode 51B has a dimension D2 in the thickness direction of the semiconductor substrate 11. The dimensional change from the first vertical electrode 51A (size D1) to the second vertical electrode 51B (size D2) results in the formation of a step sd between the first vertical electrode 51A and the second vertical electrode 51B along the thickness direction of the semiconductor substrate 11.

[0159] The above-described variations 1 to 4 also apply to the camera device 3.

[0160] For example, such as Figure 30 As shown, the distal ends of the first vertical electrode 51A and the second vertical electrode 51B may each have rounded corners CP. Alternatively, the thickness of a portion of the gate insulating film 53 may be greater than the thickness of other portions of the gate insulating film 53 (see [reference]). Figure 17 Furthermore, the vertical electrode 51 can have a planar shape other than a circle (see [reference]). Figure 18 , Figure 20 and Figure 21 Furthermore, the planar electrode 52 can have a planar shape other than a square or a rectangle (see [reference]). Figure 22 ).

[0161] Next, we will refer to Figure 31 (A) and (B) to Figure 34 (A) and (B) illustrate the method of forming the first vertical electrode 51A and the second vertical electrode 51B. Figure 31 (A) to Figure 34 (A) shows the planar (XY plane) structure of the front 11Sa side of the semiconductor substrate 11. Figure 31 (B) to Figure 34 (B) shows the corresponding Figure 23B The cross-sectional structure.

[0162] First, such as Figure 31As shown in (A) and (B), a resist film 21 with an opening 21M is formed on the front surface 11Sa of the semiconductor substrate 11. For example, the opening 21M has a circular planar shape. The opening 21M is formed at a location in the planar view that overlaps with the area where the first vertical electrode 51A will be formed. For example, the opening 21M is formed by photolithography.

[0163] Next, as Figure 32 As shown in (A) and (B), the semiconductor substrate 11 is dry-etched through the opening 21M of the resist film 21. By doing so, a groove 11VA is formed on the portion of the semiconductor substrate 11 corresponding to the opening 21M.

[0164] Subsequently, as Figure 33 As shown in (A) and (B), an opening 21MB is formed at a position spaced apart from the opening 21M. For example, the opening 21MB has a circular planar shape. The opening 21MB is formed at a position in the planar view that overlaps with the area where the second vertical electrode 51B will be formed. For example, the opening 21MB is formed by photolithography.

[0165] Next, as Figure 34 As shown in (A) and (B), the semiconductor substrate 11 is dry-etched through openings 21M and 21MB of the resist film 21. By doing so, a groove 11VB is formed on a portion of the semiconductor substrate 11 corresponding to the opening 21MB, and the groove 11VA is made deeper. Subsequently, an insulating material and a conductive material are sequentially embedded in these grooves 11VA and 11VB. By doing so, a gate insulating film 53 and a first vertical electrode 51A are formed in the groove 11VA, and a gate insulating film 53 and a second vertical electrode 51B are formed in the groove 11VB.

[0166] The imaging device 3 according to this embodiment has a transmission gate TG including a first vertical electrode 51A and a second vertical electrode 51B. In the thickness direction of the semiconductor substrate 11, the size of the second vertical electrode 51B is smaller than the size of the first vertical electrode 51A. Therefore, the signal charge retained in the transmission path can be reduced while maintaining the desired modulation amount. Thus, image quality degradation can be suppressed. Furthermore, the first vertical electrode 51A and the second vertical electrode 51B can be formed by simple photolithography and simple etching processes, making the manufacturing process easier compared to the vertical electrode 51 described in the first embodiment.

[0167] <Variation Example 6>

[0168] Figure 35A and Figure 35B The structures of the relevant parts of the camera device 3 according to the modified example 6 of the third embodiment described above are schematically shown. Figure 35AThe planar structure of each pixel P of the camera device 3 is shown, and Figure 35A Corresponding to the third embodiment described above Figure 29A . Figure 35B It shows along Figure 35A The cross-sectional structure cut by line B-B' seen in the image, and Figure 35B Corresponding to the third embodiment described above Figure 29B In this imaging device 3, the transmission gate TG includes a third vertical electrode 51C located between the first vertical electrode 51A and the second vertical electrode 51B. Furthermore, the imaging device 3 according to Modification 6 has the same structure as the imaging device 3 according to the third embodiment described above, and its function and effect are also the same.

[0169] For example, in the signal charge transport path from PD 41 to FD 42, a third vertical electrode 51C is disposed between the first vertical electrode 51A and the second vertical electrode 51B. The third vertical electrode 51C has a dimension D3 in the thickness direction of the semiconductor substrate 11. For example, this dimension D3 is smaller than the dimension D1 of the first vertical electrode 51A and larger than the dimension D2 of the second vertical electrode 51B (D1>D3>D2). A step sda is formed by the dimensional change from the first vertical electrode 51A (dimension D1) to the third vertical electrode 51C (dimension D3), and a step sdb is formed by the dimensional change from the third vertical electrode 51C (dimension D3) to the second vertical electrode 51B (dimension D2). By disposing this third vertical electrode 51C between the first vertical electrode 51A and the second vertical electrode 51B, it is easier to adjust the modulation amount. Two or more vertical electrodes of different dimensions can be separately disposed between the first vertical electrode 51A and the second vertical electrode 51B.

[0170] <Variation Example 7>

[0171] Figure 36A and Figure 36B The structures of the relevant parts of the camera device 3 according to the modified example 7 of the third embodiment described above are schematically shown. Figure 36A The planar structure of each pixel P of the camera device 3 is shown, and Figure 36A Corresponding to the third embodiment described above Figure 29A . Figure 36B It shows along Figure 36A The cross-sectional structure cut by line B-B' seen in the image, and Figure 36B Corresponding to the third embodiment described above Figure 29B Here, the transmission gate TG includes a first planar electrode 52A and a second planar electrode 52B. Furthermore, the imaging device 3 according to Modified Example 7 has the same structure as the imaging device 3 according to the third embodiment described above, and its function and effect are also the same.

[0172] First planar electrode 52A and second planar electrode 52B are disposed on the front surface 11Sa of semiconductor substrate 11, and both have, for example, a rectangular planar shape. For example, the first planar electrode 52A and the second planar electrode 52B are sequentially disposed along the signal charge transport path from PD 41 to FD 42. The first planar electrode 52A and the second planar electrode 52B are electrically isolated from each other. For example, a first vertical electrode 51A is connected to the first planar electrode 52A, and a second vertical electrode 51B is connected to the second planar electrode 52B. By dispersing the first planar electrode 52A and the second planar electrode 52B in this way, the voltage values ​​applied to the first planar electrode 52A and the second planar electrode 52B respectively can be changed. Therefore, the signal charge transport efficiency from PD 41 to FD 42 can be improved.

[0173] <Variation Example 8>

[0174] Figure 37A and Figure 37B The structures of the relevant parts of the camera device 3 according to the modified example 8 of the third embodiment described above are schematically shown. Figure 37A The planar structure of each pixel P of the camera device 3 is shown, and Figure 37A Corresponding to the third embodiment described above Figure 29A . Figure 37B It shows along Figure 37A The cross-sectional structure cut by line B-B' seen in the image, and Figure 37B Corresponding to the third embodiment described above Figure 29B Here, the transmission gate TG includes four vertical electrodes (two first vertical electrodes 51A and two second vertical electrodes 51B). Furthermore, the imaging device 3 according to Modified Example 8 has the same structure as the imaging device 3 according to the third embodiment described above, and its function and effect are also the same.

[0175] As described in the third embodiment above, the first vertical electrode 51A and the second vertical electrode 51B are sequentially arranged along the signal charge transmission path from PD 41 to FD 42. The two first vertical electrodes 51A are arranged side-by-side in a direction intersecting the signal charge transmission path (e.g., a direction perpendicular to the signal charge transmission path), and the two second vertical electrodes 51B are arranged side-by-side in the same direction. That is, in this transmission gate TG, two pairs of first vertical electrodes 51A and second vertical electrodes 51B are arranged side-by-side in a direction intersecting the signal charge transmission path. In this transmission gate TG, signal charge is transmitted to FD 42 between the two first vertical electrodes 51A and between the two second vertical electrodes 51B. Therefore, compared to the case where only one pair of first vertical electrodes 51A and second vertical electrodes 51B is provided (…),… Figure 29A and Figure 29BCompared to PD41, this shortens the signal charge transmission path and reduces the probability of signal charge being trapped in the transmission path. Therefore, the signal charge transmission efficiency from PD41 to FD42 can be improved, thereby improving image quality.

[0176] <Variation Example 9>

[0177] Figure 38 The structure of the relevant parts of each of the imaging devices 1, 2 and 3 according to the modified examples 9 of the first to third embodiments described above is schematically shown. Figure 38 The planar structure of each pixel P of camera devices 1, 2, and 3 is shown, and Figure 38 Corresponding to the first embodiment described above Figure 2 Here, the global shutter system applies to camera devices 1, 2, and 3. Furthermore, the construction of camera devices 1, 2, and 3 according to Modification 9 is the same as that of camera devices 1, 2, and 3 according to the first to third embodiments described above, and their functions and effects are also the same.

[0178] A global shutter system is a system in which, essentially, all pixels begin exposure simultaneously and all pixels end exposure simultaneously. Here, "all pixels" refers to all pixels within the portion of the image that appears, excluding dummy pixels, etc. Furthermore, when the temporal difference and distortion of the image are very small, a global shutter system includes systems where global exposure is performed in units of multiple rows (e.g., dozens of rows) while switching the area to be globally exposed, rather than simultaneously globally exposing all pixels. Additionally, a global shutter system also includes systems where, instead of globally exposing all pixels within the portion of the image that appears, global exposure is performed on pixels within a predetermined area.

[0179] Pixel P includes PD 41, transmission transistors TR and TR2, memory (MEM) 43, and FD 42. In each pixel P, transmission transistor TR is located between PD 41 and MEM 43, and transmission transistor TR2 is located between MEM 43 and FD 42. FD 42 is connected to the vertical signal line Lsig (see [reference]) via amplification transistor AMP and selection transistor SEL. Figure 2 and Figure 3 Here, the transmission gate TG of the transmission transistor TR corresponds to a specific example of the "first transmission gate" in this disclosure, and the transmission gate TG2 of the transmission transistor TR corresponds to a specific example of the "second transmission gate" in this disclosure. Furthermore, MEM 43 corresponds to a specific example of the "first charge accumulation section" in this disclosure, and FD 42 corresponds to a specific example of the "second charge accumulation section" in this disclosure.

[0180] For example, one of the source-drain pairs of the transfer transistor TR is connected to PD 41, and the other is connected to MEM43. The transfer transistor TR turns on in response to a drive signal input to its gate. This allows the signal charge generated by PD 41 to be read and transferred to MEM 43.

[0181] MEM 43 is connected to transmission transistor TR and transmission transistor TR2. MEM 43 is a charge storage unit for temporarily holding the signal charge generated by PD 41. Imaging devices 1, 2, and 3 according to this modification each include MEM 43, thereby realizing a global shutter function.

[0182] One of the source-drain pairs of the transfer transistor TR2 is connected to MEM 43, and the other is connected to FD 42. The transfer transistor TR2 turns on in response to a drive signal input to its gate. This allows the signal charge temporarily held in MEM 43 to be read and transferred to FD 42.

[0183] This disclosure also applies to imaging devices 1, 2, and 3 of such global shutter systems. For example, the transmission gate TG of the transmission transistor TR may include a first electrode portion 51a (or a first vertical electrode 51A) and a second electrode portion 51b (or a second vertical electrode 51B), and the first electrode portion 51a and the second electrode portion 51b may be arranged sequentially along the signal charge transmission path from PD 41 to MEM 43 (see [link to documentation]). Figure 4 Alternatively, the transmission gate TG2 of the transmission transistor TR2 may include a first electrode portion 51a (or a first vertical electrode 51A) and a second electrode portion 51b (or a second vertical electrode 51B), and the first electrode portion 51a and the second electrode portion 51b may be arranged sequentially along the signal charge transmission path from MEM 43 to FD 42 (see...). Figure 4 (etc.). The transmission gate TG of the transmission transistor TR and the transmission gate TG2 of the transmission transistor TR2 may each include a first electrode portion 51a (or a first vertical electrode 51A) and a second electrode portion 51b (or a second vertical electrode 51B).

[0184] In addition, camera devices 1, 2 and 3 are respectively suitable for so-called vertical stacked global shutter system camera devices.

[0185] Figure 39A and Figure 39B They are shown respectively Figure 38 Another example of the camera devices 1, 2, and 3 shown. These camera devices 1, 2, and 3 are respectively so-called vertical stacked global shutter system camera devices. Figure 39A The planar structure of the relevant portion of each pixel P in camera devices 1, 2, and 3 is shown. Figure 39B It shows alongFigure 39A The cross-sectional structure seen in the figure is taken by the B-B' line. As shown, a portion of MEM 43 can be stacked on PD 41. This makes it easy to increase the area of ​​PD 41.

[0186] This disclosure also applies to imaging devices 1, 2, and 3 of such vertically stacked global shutter systems. For example, the transmission gate TG of the transmission transistor TR may include a first electrode portion 51a (or a first vertical electrode 51A) and a second electrode portion 51b (or a second vertical electrode 51B), and the first electrode portion 51a and the second electrode portion 51b may be sequentially arranged along the signal charge transmission path from PD 41 to MEM 43. Figure 39B Alternatively, the transmission gate TG2 of the transmission transistor TR2 may include a first electrode portion 51a (or a first vertical electrode 51A) and a second electrode portion 51b (or a second vertical electrode 51B), and the first electrode portion 51a and the second electrode portion 51b may be arranged sequentially along the signal charge transmission path from MEM 43 to FD 42 (see [reference]). Figure 4 (etc.). The transmission transistors TR and TR2 may each include a first electrode portion 51a (or a first vertical electrode 51A) and a second electrode portion 51b (or a second vertical electrode 51B).

[0187] <Variation Example 10>

[0188] Figure 40 The planar structure of relevant parts of the imaging devices 1, 2 and 3 according to the modified examples 10 of the first to third embodiments described above is schematically shown. Figure 40 Corresponding to the first embodiment described above Figure 2 Here, FD 42 is shared by multiple PD 41. Furthermore, the camera devices 1, 2, and 3 according to Modification 10 have the same construction as those according to the first to third embodiments described above, and their functions and effects are also the same.

[0189] Figure 41 It shows Figure 40 Examples of equivalent circuits for camera devices 1, 2, and 3 are shown. For example, in camera devices 1, 2, and 3, signal charge is transferred from four PDs 41 to one FD 42. That is, four PDs 41 share FD 42. Although not shown, two PDs 41 can share FD 42. Alternatively, eight PDs 41 can share FD 42. The number of PDs 41 sharing FD 42 can differ from the above. As mentioned above, since FD 42 is shared by multiple PDs 41, the design flexibility of the pixel layout can be improved.

[0190] Note that in the first to third embodiments and their variations 1 to 10 described above, the conductivity type can be reversed. For example, in the first to third embodiments and their variations 1 to 9 described above, p-type can be replaced with n-type, and n-type can be replaced with p-type. Even in this case, the same effect as the first to third embodiments and their variations 1 to 9 described above can be obtained.

[0191] <Example>

[0192] Figure 42 An example of a schematic construction of a camera system 7 is shown, which includes any one of the camera devices 1, 2 and 3 (hereinafter collectively referred to as camera device 1) according to the first to third embodiments and their variations 1 to 9 described above.

[0193] For example, the camera system 7 is an electronic device. Examples of electronic devices include imaging devices such as digital cameras and camcorders, and mobile terminals such as smartphones and tablets. For example, the camera system 7 includes an optical system 241, a shutter device 242, an imaging device 1, a DSP circuit 243, a frame memory 244, a display unit 245, a storage unit 246, an operation unit 247, and a power supply unit 248. In the camera system 7, the shutter device 242, the imaging device 1, the DSP circuit 243, the frame memory 244, the display unit 245, the storage unit 246, the operation unit 247, and the power supply unit 248 are connected to each other via a bus 249.

[0194] The imaging device 1 outputs image data corresponding to the incident light. The optical system 241 includes one or more lenses and guides light (incident light) from the subject to the imaging device 1 to form an image on the light-receiving surface of the imaging device 1. A shutter device 242 is disposed between the optical system 241 and the imaging device 1, and controls the illumination and shading periods of the imaging device 1 under the control of the operation unit 247. The DSP circuit 243 is a signal processing circuit that processes the signals (image data) output from the imaging device 1. The frame memory 244 temporarily stores the image data processed by the DSP circuit 243 in frames. The display unit 245 includes, for example, a panel display such as a liquid crystal panel or an organic electroluminescence (EL) panel, and displays moving or still images captured by the imaging device 1. The storage unit 246 records the image data of the moving or still images captured by the imaging device 1 in a recording medium such as a semiconductor memory or a hard disk. The operation unit 247 outputs operation commands regarding various functions of the imaging system 7 according to the user's operation. The power supply unit 248 provides various power supplies, which serve as operating power supplies for the camera device 1, DSP circuit 243, frame memory 244, display unit 245, storage unit 246, and operation unit 247, to these power supply targets as needed.

[0195] Next, the recording process in camera system 7 will be explained.

[0196] Figure 43 An example flowchart of the camera operation in the camera system 7 is shown. The user gives a command to start recording via the operation unit 247 (step S101). In response, the operation unit 247 sends a recording command to the camera device 1 (step S102). The camera device 1 (specifically, the system control circuit 36) receives the recording command and then performs recording via the predetermined camera system (step S103).

[0197] The imaging device 1 outputs an image (image data) of light formed on the light-receiving surface by the optical system 241 and the shutter device 242 to the DSP circuit 243. Here, image data refers to the data of all pixels based on the pixel signal generated by the charge temporarily held in the FD 42. The DSP circuit 243 performs predetermined signal processing (e.g., noise reduction, etc.) based on the image data received from the imaging device 1 (step S104). The DSP circuit 243 causes the frame memory 244 to store the image data after predetermined signal processing, and the frame memory 244 causes the storage unit 246 to store the image data (step S105). The image is thus captured by the imaging system 7.

[0198] In this application example, the camera device 1 is applied to the camera system 7. Therefore, the degradation of image quality of the camera device 1 can be suppressed, thereby providing a high-quality camera system 7.

[0199] <Application Example>

[0200] (Application Example 1)

[0201] The technology disclosed herein (the Technology) is applicable to a variety of products. For example, the Technology disclosed herein can be implemented as a device mounted on any type of mobile body, such as: automobiles, electric vehicles, hybrid vehicles, motorcycles, bicycles, personal mobile devices, airplanes, drones, ships, and robots.

[0202] Figure 44 This is a block diagram illustrating a schematic construction example of a vehicle control system that is an example of a mobile body control system capable of applying the technology according to embodiments of the present disclosure.

[0203] The vehicle control system 12000 includes multiple electronic control units interconnected via a communication network 12001. Figure 44In the example shown, the vehicle control system 12000 includes: a drive system control unit 12010, a body system control unit 12020, an external information detection unit 12030, an internal information detection unit 12040, and an integrated control unit 12050. Furthermore, as part of the functional configuration of the integrated control unit 12050, a microcomputer 12051, an audio / image output unit 12052, and an in-vehicle network interface (I / F) 12053 are shown.

[0204] The drive system control unit 12010 controls the operation of equipment related to the vehicle's drive system according to various programs. For example, the drive system control unit 12010 serves as a control device for the following devices: drive force generating devices such as internal combustion engines or drive motors for generating drive force for the vehicle; drive force transmission mechanisms for transmitting drive force to the wheels; steering mechanisms for adjusting the vehicle's steering angle; and braking devices for generating braking force for the vehicle.

[0205] The body system control unit 12020 controls the operation of various devices installed on the vehicle body according to various programs. For example, the body system control unit 12020 acts as a control device for devices such as: keyless entry systems; smart key systems; power windows; or various lights such as headlights, taillights, brake lights, turn signals, or fog lights. In this case, radio waves or signals from various switches transmitted from a mobile device that replaces the key can be input to the body system control unit 12020. The body system control unit 12020 receives these input radio waves or signals and controls the vehicle's door locks, power windows, lights, etc.

[0206] The exterior information detection unit 12030 detects information about the exterior of the vehicle, including information from the vehicle control system 12000. For example, the exterior information detection unit 12030 is connected to a camera unit 12031. The exterior information detection unit 12030 causes the camera unit 12031 to capture images of the exterior of the vehicle and receives the captured images. Based on the received images, the exterior information detection unit 12030 can perform object detection processing or distance detection processing for objects such as pedestrians, vehicles, obstacles, signs, or letters on the road surface.

[0207] The camera unit 12031 is an optical sensor that receives light and outputs an electrical signal corresponding to the amount of light received. The camera unit 12031 can output the electrical signal as an image or as ranging information. Furthermore, the light received by the camera unit 12031 can be visible light or non-visible light such as infrared light.

[0208] The in-vehicle information detection unit 12040 detects information inside the vehicle. For example, the in-vehicle information detection unit 12040 is connected to a driver state detection unit 12041 for detecting the driver's state. The driver state detection unit 12041 includes, for example, a camera for capturing images of the driver. Based on the detection information input from the driver state detection unit 12041, the in-vehicle information detection unit 12040 can calculate the driver's level of fatigue or concentration, or determine whether the driver is dozing off.

[0209] Based on information acquired by the external or internal information detection unit 12030 or the internal information detection unit 12040, the microcomputer 12051 can calculate the control target values ​​for the drive force generating device, steering mechanism, or braking device, and can output control commands to the drive system control unit 12010. For example, the microcomputer 12051 can perform cooperative control aimed at realizing the functions of an advanced driver assistance system (ADAS), including: collision avoidance or impact mitigation, following distance-based driving, speed maintenance, collision warning, or lane departure warning.

[0210] In addition, the microcomputer 12051 can control the drive force generating device, steering mechanism or braking device, etc., based on the external or internal information of the vehicle obtained by the external information detection unit 12030 or the internal information detection unit 12040, thereby performing cooperative control aimed at achieving autonomous driving and the like, which is intended to enable the vehicle to drive autonomously without the driver's operation.

[0211] Furthermore, based on the information about the exterior of the vehicle acquired by the exterior information detection unit 12030, the microcomputer 12051 can output control commands to the body system control unit 12020. For example, the microcomputer 12051 can control the headlights and switch the high beams to low beams based on the position of the vehicle in front or oncoming vehicles detected by the exterior information detection unit 12030, thereby performing cooperative control aimed at reducing glare.

[0212] The sound / image output unit 12052 sends an output signal of at least one of sound and image to an output device capable of visually or audibly notifying passengers in the vehicle or outside the vehicle of information. Figure 44 In the example, an audio speaker 12061, a display unit 12062, and an instrument panel 12063 are shown as output devices. The display unit 12062 may include, for example, at least one of an on-board display and a head-up display.

[0213] Figure 45 This is a diagram showing an example of the mounting position of the camera unit 12031.

[0214] exist Figure 45 In the middle, the camera unit 12031 includes camera units 12101, 12102, 12103, 12104 and 12105.

[0215] Cameras 12101, 12102, 12103, 12104, and 12105 are installed, for example, at the front nose, rearview mirrors, rear bumper, and rear door of vehicle 12100, as well as at the upper part of the windshield inside the vehicle. Camera 12101 at the front nose and camera 12105 at the upper part of the windshield inside the vehicle primarily acquire images of the front of vehicle 12100. Cameras 12102 and 12103 at the rearview mirrors primarily acquire images of the sides of vehicle 12100. Camera 12104 at the rear bumper or rear door primarily acquires images of the rear of vehicle 12100. Camera 12105 at the upper part of the windshield inside the vehicle is mainly used to detect vehicles ahead, pedestrians, obstacles, traffic lights, traffic signs, or lanes.

[0216] Incidentally, Figure 45 Examples of the shooting ranges of camera units 12101 to 12104 are shown. Camera range 12111 represents the shooting range of camera unit 12101 located on the front nose. Camera ranges 12112 and 12113 represent the shooting ranges of camera units 12102 and 12103 located on the rearview mirrors, respectively. Camera range 12114 represents the shooting range of camera unit 12104 located on the rear bumper or rear door. For example, by superimposing the image data captured by camera units 12101 to 12104, a bird's-eye view of the vehicle 12100 as seen from above is obtained.

[0217] At least one of the camera units 12101 to 12104 may have the function of acquiring distance information. For example, at least one of the camera units 12101 to 12104 may be a stereo camera composed of multiple camera elements, or may be a camera element having pixels for phase difference detection.

[0218] For example, the microcomputer 12051 can determine the distance to each three-dimensional object within the camera range 12111-12114 and the change of that distance over time (relative speed to the vehicle 12100) based on distance information obtained from the camera units 12101-12104. This allows it to extract the closest three-dimensional object, specifically on the road where the vehicle 12100 is traveling and moving in almost the same direction as the vehicle 12100 at a predetermined speed (e.g., greater than or equal to 0 km / h), as the preceding vehicle. Furthermore, the microcomputer 12051 can preset a following distance to be maintained in front of the preceding vehicle and can perform automatic braking control (including follow-stop control) or automatic acceleration control (including follow-start control), etc. Therefore, cooperative control aimed at achieving autonomous driving, etc., that allows the vehicle to drive itself without relying on driver operation, can be performed.

[0219] For example, based on distance information obtained from cameras 12101-12104, microcomputer 12051 can classify three-dimensional object data about three-dimensional objects into three-dimensional object data for two-wheeled vehicles, standard vehicles, large vehicles, pedestrians, utility poles, and other three-dimensional objects, extract the classified three-dimensional object data, and use the extracted three-dimensional object data to automatically avoid obstacles. For example, microcomputer 12051 identifies obstacles around vehicle 12100 as obstacles visible to the driver of vehicle 12100 and obstacles difficult for the driver of vehicle 12100 to see. Then, microcomputer 12051 determines a collision risk to represent the risk 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, microcomputer 12051 outputs a warning to the driver through audio speaker 12061 or display unit 12062, and performs forced deceleration or evasive steering through drive system control unit 12010. Therefore, microcomputer 12051 can assist driving to avoid collisions.

[0220] At least one of the camera units 12101 to 12104 can be an infrared camera for detecting infrared light. For example, the microcomputer 12051 can identify a pedestrian by determining whether a pedestrian exists in the images captured by the camera units 12101 to 12104. For example, this pedestrian identification is performed by: extracting feature points from the images captured by the camera units 12101 to 12104, which are infrared cameras; and determining whether the object is a pedestrian by performing pattern matching processing on a series of feature points representing the outline of the object. When the microcomputer 12051 determines that a pedestrian exists in the images captured by the camera units 12101 to 12104 and identifies the pedestrian, the sound / image output unit 12052 controls the display unit 12062 to overlay and display a rectangular outline for emphasis on the identified pedestrian. The sound / image output unit 12052 can also control the display unit 12062 to display an icon or the like representing a pedestrian at a desired location.

[0221] The foregoing has already provided an example of a mobile body control system to which the technology of this disclosure is applicable. The technology of this disclosure is applicable to the camera unit 12031 in the above-described configuration. Specifically, the camera device 1 according to any of the above embodiments and variations is applicable to the camera unit 12031. By applying the technology of this disclosure to the camera unit 12031, high-definition captured images with low noise can be obtained, thereby enabling high-precision control through the mobile body control system using the captured images.

[0222] (Application Example 2)

[0223] Figure 46 This is a diagram illustrating an example of a schematic construction of an endoscopic surgical system capable of applying the technology (the technology) according to embodiments of this disclosure.

[0224] exist Figure 46 The image shows a surgeon (physician) 11131 performing surgery on a patient 11132 on a bed 11133 using an endoscopic surgical system 11000. As shown, the endoscopic surgical system 11000 includes an endoscope 11100, other surgical instruments 11110 such as a pneumoperitoneum tube 11111 and an energy device 11112, a support arm device 11120 for supporting the endoscope 11100, and a trolley 11200 equipped with various devices for endoscopic surgery.

[0225] Endoscope 11100 includes: a tube 11101, a region having a predetermined length extending from the distal end of the tube 11101 being inserted into a body cavity of a patient 11132; and a camera 11102, the camera 11102 being connected to the proximal end of the tube 11101. In the example shown, an endoscope 11100 configured as a rigid endoscope with a rigid tube 11101 is illustrated. However, endoscope 11100 may also be configured as a flexible endoscope with a flexible tube 11101.

[0226] The endoscope 11101 has an opening at its distal end for mounting an objective lens. A light source device 11203 is connected to the endoscope 11100 such that light generated by the light source device 11203 is guided to the distal end of the endoscope 11101 via a light guide extending within the endoscope 11101, and this light is then projected onto the object of observation within the body cavity of the patient 11132 via the aforementioned objective lens. It should be noted that the endoscope 11100 may be a forward-viewing endoscope, or an oblique-viewing endoscope, or a side-viewing endoscope.

[0227] An optical system and an imaging element are provided within the camera 11102, such that reflected light (observation light) from the observed target is converged onto the imaging element by the optical system. The observation light undergoes photoelectric conversion by the imaging element, generating an electrical signal corresponding to the observation light, i.e., an image signal corresponding to the observed image. This image signal is sent as raw data to the CCU 11201.

[0228] The CCU 11201 includes a central processing unit (CPU) or a graphics processing unit (GPU), and the CCU 11201 controls the operation of the endoscope 11100 and the display device 11202 as a whole. Furthermore, the CCU 11201 receives image signals from the camera 11102 and performs various image processing operations on the image signals, such as image processing (de-mosaicing), for displaying images based on the image signals.

[0229] Under the control of CCU 11201, display device 11202 displays an image based on an image signal (which has been image processed by CCU 11201).

[0230] For example, the light source device 11203 includes a light source such as a light emitting diode (LED) and provides illumination light for imaging the surgical area to the endoscope 11100.

[0231] Input device 11204 is the input interface of endoscopic surgery system 11000. Users can input various information or commands into endoscopic surgery system 11000 through input device 11204. For example, users can input commands to change the imaging conditions of endoscope 11100 (type of illumination light, magnification, or focal length, etc.).

[0232] The procedure control device 11205 controls the drive of the energy device 11112 used for tissue cauterization or cutting, or sealing of blood vessels, etc. The pneumoperitoneum device 11206 injects gas into the patient's body cavity 11132 through the pneumoperitoneum tube 11111 to inflate the cavity, thereby ensuring the field of vision of the endoscope 11100 and ensuring the surgeon's working space. 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, images, or charts.

[0233] It should be noted that the light source device 11203 that provides illumination light to the endoscope 11100 for imaging the surgical area may include a white light source, such as an LED, a laser light source, or a combination of LEDs and laser light sources. When the white light source includes a combination of red, green, and blue (RGB) laser light sources, the white balance of the captured image can be adjusted by the light source device 11203 because the output intensity and timing of each color (wavelength) can be controlled with high precision. Furthermore, in this case, if the object being observed is illuminated time-divisionally using laser beams from each of the RGB laser light sources, and the driving of the imaging element of the camera 11102 is controlled synchronously with the illumination timing, images corresponding to the R, G, and B colors can also be captured time-divisionally. According to this method, color images can be obtained even if a color filter is not provided in the imaging element.

[0234] Furthermore, the light source device 11203 can be controlled to change the light intensity to be output at predetermined intervals. By controlling the driving of the imaging element of the camera 11102 in sync with the moment of light intensity change and acquiring images in a time-divisional manner, and then synthesizing these images, it is possible to produce high dynamic range images without underexposed blocked-up shadows and overexposed highlights.

[0235] Furthermore, the light source device 11203 can be configured to provide light of a predetermined wavelength band prepared for special light observation. In special light observation, for example, narrow-band imaging (narrow-band imaging) is performed to image predetermined tissues, such as blood vessels in the superficial portion of a mucosa, with high contrast by irradiating a narrow-band light compared to the illumination light used in ordinary observation (i.e., white light) using the wavelength dependence of light absorption in body tissue. Alternatively, fluorescence observation can be performed in special light observation to obtain an image based on the fluorescence generated by irradiation with excitation light. In fluorescence observation, fluorescence observation from body tissue can be performed by irradiating the body tissue with excitation light (autofluorescence observation), or a fluorescence image can be obtained by locally injecting a reagent such as indocyanine green (ICG) into the body tissue and irradiating the body tissue with excitation light corresponding to the fluorescence wavelength of the reagent. The light source device 11203 can be configured to provide such narrow-band light and / or excitation light suitable for special light observation as described above.

[0236] Figure 47 It shows Figure 46 A block diagram illustrating an example of the functional configuration of the camera 11102 and CCU 11201.

[0237] Camera 11102 includes a lens unit 11401, an image capture unit 11402, a drive unit 11403, a communication unit 11404, and a camera control unit 11405. CCU 11201 includes a communication unit 11411, an image processing unit 11412, and a control unit 11413. Camera 11102 and CCU 11201 are communicatively connected to each other via a transmission cable 11400.

[0238] Lens unit 11401 is an optical system disposed at the connection position with lens barrel 11101. Observation light obtained from the distal end of lens barrel 11101 is guided to camera 11102 and introduced into lens unit 11401. Lens unit 11401 includes a combination of multiple lenses, including zoom lenses and focusing lenses.

[0239] The number of imaging elements included in the imaging unit 11402 can be one (single-plate type) or multiple (multi-plate type). For example, when the imaging unit 11402 is configured as a multi-plate type imaging unit, the imaging elements generate image signals corresponding to R, G, and B respectively, and these image signals can be synthesized to obtain a color image. The imaging unit 11402 can also be configured to have a pair of imaging elements to acquire right-eye image signals and left-eye image signals respectively for three-dimensional (3D) display. If 3D display is performed, the surgeon 11131 can more accurately determine the depth of living tissue in the surgical site. It should be noted that when the imaging unit 11402 is configured as a stereoscopic imaging element, multiple system lens units 11401 are arranged in a manner corresponding to each imaging element.

[0240] Furthermore, the camera unit 11402 does not necessarily need to be mounted on the camera 11102. For example, the camera unit 11402 can be mounted inside the lens barrel 11101 immediately behind the objective lens.

[0241] The drive unit 11403 includes an actuator, and under the control of the camera control unit 11405, the drive unit 11403 moves the zoom lens and focusing lens of the lens unit 11401 a predetermined distance along the optical axis. Therefore, the magnification and focus of the image captured by the imaging unit 11402 can be appropriately adjusted.

[0242] Communication unit 11404 includes a communication device for transmitting various types of information to and receiving various types of information from CCU 11201. Communication unit 11404 transmits image signals acquired from camera unit 11402 as RAW data to CCU 11201 via transmission cable 11400.

[0243] Additionally, the communication unit 11404 receives control signals from the CCU 11201 for controlling the camera 11102 and supplies these control signals to the camera control unit 11405. For example, the control signals include information related to shooting conditions, such as information specifying the frame rate of the captured image, information specifying the exposure value during shooting, and / or information specifying the magnification and focus of the captured image.

[0244] It should be noted that imaging conditions such as frame rate, exposure value, magnification, or focus can be specified by the user or automatically set by the control unit 11413 of CCU 11201 based on the acquired image signal. In the latter case, the automatic exposure (AE), automatic focus (AF), and automatic white balance (AWB) functions are integrated into the endoscope 11100.

[0245] The camera control unit 11405 controls the driving of the camera 11102 based on the control signals received from the CCU 11201 via the communication unit 11404.

[0246] The communication unit 11411 includes a communication device for transmitting various information to and receiving various information from the camera 11102. The communication unit 11411 receives image signals transmitted from the camera 11102 via a transmission cable 11400.

[0247] In addition, the communication unit 11411 transmits control signals for controlling the camera 11102 to the camera 11102. The image signals and control signals can be transmitted via electrical communication or optical communication, etc.

[0248] The image processing unit 11412 performs various image processing on the image signal in RAW data form transmitted from the camera 11102.

[0249] The control unit 11413 performs various controls related to the endoscope 11100 capturing images of the surgical site, etc., and displaying the images obtained by capturing images of the surgical site, etc. For example, the control unit 11413 generates control signals for controlling the drive of the camera 11102.

[0250] Furthermore, the control unit 11413 controls the display device 11202 based on the image signal that has already been processed by the image processing unit 11412, to display the captured image obtained by photographing the surgical site, etc. Thus, the control unit 11413 can use various image recognition technologies to identify various objects in the captured image. For example, the control unit 11413 can identify surgical instruments such as forceps, specific living areas, bleeding, and fogging when using the energy device 11112 by detecting the shape and color of the edges of objects included in the captured image. When the control unit 11413 controls the display device 11202 to display the captured image, the control unit 11413 can use the recognition results to display various surgical support information in an overlay manner along with the image of the surgical site. By displaying surgical support information in an overlay manner and presenting it to the surgeon 11131, the workload of the surgeon 11131 can be reduced, and the surgeon 11131 can perform the surgery with certainty.

[0251] The transmission cable 11400 connecting the camera 11102 and the CCU 11201 is an electrical signal cable prepared for electrical signal communication, an optical fiber prepared for optical communication, or a composite cable prepared for both electrical and optical communication.

[0252] In the example shown here, although communication is carried out via wired communication using transmission cable 11400, communication between camera 11102 and CCU 11201 can also be carried out via wireless communication.

[0253] Examples of endoscopic surgical systems to which the technology according to this disclosure applies have been described above. The technology according to this disclosure applies to the camera unit 11402 in the camera 11102 of the endoscope 11100 as described above. By applying the technology according to this disclosure to the camera unit 11402, degradation of the image quality of the camera unit 11402 can be suppressed, thereby providing a high-quality endoscope 11100.

[0254] Although the present disclosure has been described above with reference to the first to third embodiments, variations 1 to 9, usage examples, and application examples, the present disclosure is not limited to the above embodiments, and the present disclosure can be modified in various ways. For example, in the above embodiments, the case in which multiple pixel driving lines Lread extend in the row direction and multiple vertical signal lines Lsig extend in the column direction was described as an example, but the pixel driving lines Lread and the vertical signal lines Lsig can also extend in the same direction. Furthermore, the extension direction of the pixel driving lines Lread can be changed to the vertical direction, etc., as needed.

[0255] The effects described in the above embodiments are merely exemplary, and the effects of this disclosure may be other effects, or may include other effects.

[0256] Note that this disclosure may include the following configurations. A solid-state imaging device having any of the following configurations and an electronic device including a solid-state imaging device each have a first transmission gate including a first electrode portion and a second electrode portion. In the thickness direction of the semiconductor substrate, the size of the second electrode portion is smaller than the size of the first electrode portion. Therefore, while maintaining a predetermined modulation amount, the signal charge retained in the transmission path can be reduced. Thus, image quality degradation can be suppressed.

[0257] (1) A solid-state camera device, comprising:

[0258] Semiconductor substrate;

[0259] A photoelectric conversion unit having a predetermined dimension in the thickness direction of the semiconductor substrate;

[0260] A first charge accumulation section is disposed in the semiconductor substrate and accumulates the signal charge generated by the photoelectric conversion section; and

[0261] The transmission gate includes a first electrode portion and a second electrode portion. The first electrode portion is embedded in the semiconductor substrate, has a first dimension in the thickness direction of the semiconductor substrate, and is disposed on the side of the photoelectric conversion portion. The second electrode portion is selectively disposed at a position closer to the first charge accumulation portion than the first electrode portion, and has a second dimension in the thickness direction of the semiconductor substrate that is smaller than the first dimension.

[0262] (2) The solid-state imaging device according to (1), wherein the transmission gate includes a vertical electrode and a planar electrode, the vertical electrode includes a first electrode portion and a second electrode portion, and the planar electrode is disposed on the front side of the semiconductor substrate and connected to the vertical electrode.

[0263] (3) The solid-state camera device according to (2), wherein,

[0264] The first electrode portion is disposed adjacent to the photoelectric conversion portion, and the second electrode portion is disposed adjacent to the first charge accumulation portion.

[0265] The dimensions of the vertical electrode in the thickness direction of the semiconductor substrate include a first dimension as the maximum dimension and a second dimension as the minimum dimension.

[0266] (4) The solid-state imaging device according to (2) or (3), wherein the dimension of the vertical electrode in the thickness direction of the semiconductor substrate gradually decreases or decreases stepwise from the photoelectric conversion section to the first charge accumulation section.

[0267] (5) The solid-state imaging device according to any one of (2) to (4), wherein the vertical electrode has an inclined surface connecting the first electrode portion and the second electrode portion.

[0268] (6) The solid-state imaging device according to any one of (2) to (4), wherein the vertical electrode has at least one step in the thickness direction of the semiconductor substrate between the first electrode portion and the second electrode portion.

[0269] (7) The solid-state camera device according to (2) or (3), wherein the vertical electrode includes a first vertical electrode and a second vertical electrode, the first vertical electrode includes a first electrode portion, and the second vertical electrode includes a second electrode portion and is disposed separately from the first vertical electrode.

[0270] (8) The solid-state imaging device according to (7), wherein the vertical electrode further includes a third vertical electrode located between the first vertical electrode and the second vertical electrode, wherein the dimension of the third vertical electrode in the thickness direction of the semiconductor substrate is smaller than the first dimension and larger than the second dimension.

[0271] (9) The solid-state imaging device according to (7) or (8), wherein the planar electrode includes a first planar electrode and a second planar electrode, the first planar electrode being connected to the first vertical electrode, and the second planar electrode being connected to the second vertical electrode and electrically isolated from the first planar electrode.

[0272] (10) The solid-state imaging device according to any one of (2) to (9), wherein the distal end of the vertical electrode has a rounded corner.

[0273] (11) The solid-state imaging device according to any one of (2) to (10) further includes a gate insulating film disposed between the semiconductor substrate and the transmission gate.

[0274] (12) The solid-state imaging device according to (11), wherein the thickness of the portion of the gate insulating film disposed between the vertical electrode and the semiconductor substrate is greater than the thickness of the other portions of the gate insulating film.

[0275] (13) The solid-state camera device according to (12), wherein the portion is disposed near the distal end of the vertical electrode.

[0276] (14) The solid-state imaging device according to any one of (2) to (13), wherein the vertical electrode has a planar shape that gradually narrows from the photoelectric conversion section to the first charge accumulation section.

[0277] (15) The solid-state imaging device according to any one of (2) to (14), wherein the planar electrode has a planar shape that gradually narrows from the photoelectric conversion section to the first charge accumulation section.

[0278] (16) The solid-state imaging device according to any one of (2) to (15), wherein the transmission gate includes a plurality of vertical electrodes arranged side by side along a direction intersecting the transmission path of the signal charge from the photoelectric conversion unit to the first charge accumulation unit.

[0279] (17) The solid-state imaging device according to any one of (1) to (16) further includes a second charge accumulation unit, wherein the signal charge is transferred from the first charge accumulation unit to the second charge accumulation unit, wherein,

[0280] The transmission gate includes at least one of a first transmission gate or a second transmission gate, wherein the first transmission gate transmits the signal charge from the photoelectric conversion unit to the first charge accumulation unit, and the second transmission gate transmits the signal charge from the first charge accumulation unit to the second charge accumulation unit.

[0281] (18) The solid-state imaging device according to any one of (1) to (17), wherein the signal charge is transferred from a plurality of the photoelectric conversion units to a first charge accumulation unit.

[0282] (19) An electronic device comprising a solid-state camera, the solid-state camera comprising:

[0283] Semiconductor substrate;

[0284] A photoelectric conversion unit having a predetermined dimension in the thickness direction of the semiconductor substrate;

[0285] A first charge accumulation section is disposed in the semiconductor substrate and accumulates the signal charge generated by the photoelectric conversion section; and

[0286] The transmission gate includes a first electrode portion and a second electrode portion. The first electrode portion is embedded in the semiconductor substrate, has a first dimension in the thickness direction of the semiconductor substrate, and is disposed on the side of the photoelectric conversion portion. The second electrode portion is selectively disposed at a position closer to the first charge accumulation portion than the first electrode portion, and has a second dimension in the thickness direction of the semiconductor substrate that is smaller than the first dimension.

[0287] (20) A camera device comprising:

[0288] Semiconductor substrate;

[0289] The photoelectric conversion element in the semiconductor substrate;

[0290] A transmission transistor, wherein the transmission transistor includes a transmission gate; and

[0291] The charge accumulation portion in the semiconductor substrate

[0292] The transmission gate includes a vertical electrode extending from a first surface of the semiconductor substrate along the depth direction.

[0293] The vertical electrode includes a first electrode portion embedded in the semiconductor substrate on the photoelectric conversion element side of the vertical electrode.

[0294] The transmission gate includes a second electrode portion embedded in the semiconductor substrate on the charge accumulation side of the vertical electrode.

[0295] Wherein, the distal end of the first electrode portion extends from the first surface of the semiconductor substrate to a first distance.

[0296] Wherein, the distal end of the second electrode portion extends from the first surface of the semiconductor substrate to a second distance, and

[0297] Wherein, the first distance is greater than the second distance.

[0298] (21) The camera device according to (20), wherein the transmission gate further includes a planar electrode on the first surface of the semiconductor substrate, and wherein the first electrode portion and the second electrode portion are connected to the planar electrode.

[0299] (22) The imaging device according to (20) or (21), wherein the first electrode portion is connected to the second electrode portion to form a single vertical electrode, and wherein the vertical electrode has a circular shape in a cross-section taken along a plane parallel to the plane of the first surface of the semiconductor substrate.

[0300] (23) The imaging device according to any one of (20) to (22), wherein the distal ends of the first electrode portion and the second electrode portion form an inclined surface.

[0301] (24) The camera device according to (23), wherein the distal end of the first electrode portion further includes a rounded corner portion.

[0302] (25) The imaging device according to any one of (20) to (24) further includes a gate insulating film, wherein the gate insulating film is disposed between the vertical electrode and the semiconductor substrate.

[0303] (26) The imaging device according to any one of (20) to (24) further includes a gate insulating film, wherein the gate insulating film is disposed between the vertical electrode and the semiconductor substrate, and wherein the thickness of the gate insulating film is greatest near the deepest point at the distal end of the first electrode portion.

[0304] (27) The imaging device according to any one of (20) to (26), wherein the first electrode portion is connected to the second electrode portion to form a single vertical electrode, and wherein, in a cross-section taken along a plane parallel to the plane of the first surface of the semiconductor substrate, the vertical electrode has a shape that gradually narrows from a wide portion adjacent to the photoelectric conversion element to a narrow portion adjacent to the charge accumulation portion.

[0305] (28) The imaging device according to any one of (20) to (26), wherein the first electrode portion is connected to the second electrode portion to form a single vertical electrode, and wherein the vertical electrode has a triangular shape in a cross section taken along a plane parallel to the plane of the first surface of the semiconductor substrate.

[0306] (29) The imaging device according to any one of (20) to (26), wherein the first electrode portion is connected to the second electrode portion to form a single vertical electrode, and wherein the vertical electrode has a semi-circular shape in a cross section taken along a plane parallel to the plane of the first surface of the semiconductor substrate.

[0307] (30) The camera device according to (29), wherein the circular portion of the semicircular shape faces the charge accumulation portion.

[0308] (31) The imaging device according to any one of (20) to (26), wherein the first electrode portion is connected to the second electrode portion to form a single vertical electrode, and wherein the vertical electrode has a polygonal shape in a cross section taken along a plane parallel to the plane of the first surface of the semiconductor substrate.

[0309] (32) The imaging device according to (31), wherein the planar electrode gradually narrows from a wide portion adjacent to the photoelectric conversion element to a narrow portion adjacent to the charge accumulation portion.

[0310] (33) The imaging device according to any one of (20) to (22) or (25) to (32), wherein the distal end of the first electrode portion has a surface parallel to the first surface of the semiconductor substrate, and wherein the distal end of the second electrode portion has a surface parallel to the first surface of the semiconductor substrate.

[0311] (34) The imaging device according to (33), wherein the first electrode portion is connected to the second electrode portion to form a single vertical electrode, and wherein the vertical electrode has a circular shape in at least a first cross-section taken along a plane parallel to the plane of the first surface of the semiconductor substrate near the plane electrode.

[0312] (35) The imaging device according to any one of (20) to (34), wherein the vertical electrode further includes a third electrode portion embedded in the semiconductor substrate, wherein the distal end of the third electrode portion is at a third distance from the first surface of the semiconductor substrate, and wherein the third distance is greater than the second distance and less than the first distance.

[0313] (36) The camera device according to (35), wherein the first electrode portion, the second electrode portion and the third electrode portion are spaced apart from each other.

[0314] (37) The camera device according to (20), wherein the transmission gate further includes a planar electrode having a first planar portion and a second planar portion, wherein the first planar portion and the second planar portion are spaced apart, wherein the first electrode portion extends from the first planar portion and the second electrode portion extends from the second planar portion.

[0315] (38) The camera device according to (37), wherein the width of the distal portion of the first electrode portion is less than the width of the first electrode portion at the first planar portion, and wherein the width of the distal portion of the second electrode portion is less than the width of the second electrode portion at the second planar portion.

[0316] (39) An electronic device comprising:

[0317] Optical system;

[0318] A camera device, wherein the optical system forms an image on the camera device, the camera device comprising:

[0319] Semiconductor substrate;

[0320] The photoelectric conversion element in the semiconductor substrate;

[0321] A transmission transistor, wherein the transmission transistor includes a transmission gate; and

[0322] The charge accumulation portion in the semiconductor substrate

[0323] The transmission gate includes a vertical electrode extending from a first surface of the semiconductor substrate along the depth direction.

[0324] The vertical electrode includes a first electrode portion embedded in the semiconductor substrate on the photoelectric conversion element side of the vertical electrode.

[0325] The transmission gate includes a second electrode portion embedded in the semiconductor substrate on the charge accumulation side of the vertical electrode.

[0326] Wherein, the distal end of the first electrode portion extends from the first surface of the semiconductor substrate to a first distance.

[0327] Wherein, the distal end of the second electrode portion extends from the first surface of the semiconductor substrate to a second distance, and

[0328] Wherein, the first distance is greater than the second distance; and

[0329] A processing unit, wherein the processing unit processes image data output from the camera device.

[0330] Those skilled in the art will understand that various modifications, combinations, sub-combinations and alterations can be made according to design requirements and other factors, as long as such modifications, combinations, sub-combinations and alterations are within the scope of the appended claims or their equivalents.

[0331] List of reference numerals

[0332] 1, 2, 3: Camera device

[0333] 7: Camera System

[0334] 10P: Light receiving area

[0335] 10B: Surrounding Area

[0336] 11: Semiconductor substrate

[0337] 11Sa: Front

[0338] 11Sb: Back side

[0339] 41: PD

[0340] 42: FD

[0341] 43: MEM

[0342] 51: Vertical electrode

[0343] 51A: First vertical electrode

[0344] 51B: Second vertical electrode

[0345] 51C: Third vertical electrode

[0346] 51a: First electrode section

[0347] 51b: Second electrode section

[0348] 51c: Third electrode section

[0349] 52: Planar electrode

[0350] 52A: First planar electrode

[0351] 52B: Second planar electrode

[0352] 53: Gate insulating film

[0353] TR, TR2: Transmission transistors

[0354] RST: Reset transistor

[0355] AMP: Amplifying Transistor

[0356] SEL: Select Transistor

[0357] P: pixel

[0358] D1, D2, D3: Dimensions

Claims

1. A camera device, comprising: Semiconductor substrate; The photoelectric conversion element in the semiconductor substrate; A transmission transistor, wherein the transmission transistor includes a transmission gate; and The charge accumulation portion in the semiconductor substrate The transmission gate includes a vertical electrode extending from a first surface of the semiconductor substrate along the depth direction. The vertical electrode includes a first electrode portion embedded in the semiconductor substrate on the photoelectric conversion element side of the vertical electrode. The transmission gate includes a second electrode portion embedded in the semiconductor substrate on the charge accumulation side of the vertical electrode. Wherein, the distal end of the first electrode portion extends from the first surface of the semiconductor substrate to a first distance. Wherein, the distal end of the second electrode portion extends from the first surface of the semiconductor substrate to a second distance, and Wherein, the first distance is greater than the second distance. The gate insulating film is disposed between the vertical electrode and the semiconductor substrate, and the thickness of the gate insulating film is greatest near the deepest point at the distal end of the first electrode portion.

2. The camera device according to claim 1, wherein, The transmission gate further includes a planar electrode on the first surface of the semiconductor substrate, wherein the first electrode portion and the second electrode portion are connected to the planar electrode.

3. The camera device according to claim 2, wherein, The first electrode portion is connected to the second electrode portion to form a single vertical electrode, wherein the vertical electrode has a circular shape in a cross-section taken along a plane parallel to the plane of the first surface of the semiconductor substrate.

4. The camera device according to claim 3, wherein, The distal ends of the first electrode portion and the distal ends of the second electrode portion form an inclined surface.

5. The camera device according to claim 4, wherein, The distal end of the first electrode portion also includes a rounded corner.

6. The camera device according to claim 2, wherein, The first electrode portion is connected to the second electrode portion to form a single vertical electrode, wherein, in a cross-section taken along a plane parallel to the plane of the first surface of the semiconductor substrate, the vertical electrode has a shape that gradually narrows from a wide portion adjacent to the photoelectric conversion element to a narrow portion adjacent to the charge accumulation portion.

7. The camera device according to claim 2, wherein, The first electrode portion is connected to the second electrode portion to form a single vertical electrode, wherein the vertical electrode has a triangular shape in a cross-section taken along a plane parallel to the plane of the first surface of the semiconductor substrate.

8. The camera device according to claim 2, wherein, The first electrode portion is connected to the second electrode portion to form a single vertical electrode, wherein the vertical electrode has a semi-circular shape in a cross-section taken along a plane parallel to the plane of the first surface of the semiconductor substrate.

9. The camera device according to claim 8, wherein, The circular portion of the semicircle faces the charge accumulation portion.

10. The camera device according to claim 2, wherein, The first electrode portion is connected to the second electrode portion to form a single vertical electrode, wherein the vertical electrode has a polygonal shape in a cross-section taken along a plane parallel to the plane of the first surface of the semiconductor substrate.

11. The camera device according to claim 10, wherein, The planar electrode gradually narrows from the wide portion adjacent to the photoelectric conversion element to the narrow portion adjacent to the charge accumulation portion.

12. The camera device according to claim 2, wherein, The distal end of the first electrode portion has a surface parallel to the first surface of the semiconductor substrate, and wherein the distal end of the second electrode portion has a surface parallel to the first surface of the semiconductor substrate.

13. The camera device according to claim 12, wherein, The first electrode portion is connected to the second electrode portion to form a single vertical electrode, and wherein the vertical electrode has a circular shape in at least a first cross-section taken along a plane parallel to the plane of the first surface of the semiconductor substrate near the plane of the planar electrode.

14. The camera device according to claim 2, wherein, The vertical electrode further includes a third electrode portion embedded in the semiconductor substrate, wherein the distal end of the third electrode portion is a third distance away from the first surface of the semiconductor substrate, and wherein the third distance is greater than the second distance and less than the first distance.

15. The camera device according to claim 14, wherein, The first electrode portion, the second electrode portion, and the third electrode portion are spaced apart from each other.

16. The camera device according to claim 1, wherein, The transmission gate further includes a planar electrode having a first planar portion and a second planar portion, wherein the first planar portion and the second planar portion are spaced apart, wherein the first electrode portion extends from the first planar portion and the second electrode portion extends from the second planar portion.

17. The camera device according to claim 16, wherein, The width of the distal portion of the first electrode portion is smaller than the width of the first electrode portion at the first planar portion, and wherein the width of the distal portion of the second electrode portion is smaller than the width of the second electrode portion at the second planar portion.

18. An electronic device comprising: Optical system; A camera device, wherein the optical system forms an image on the camera device, the camera device being the camera device according to any one of claims 1-17; and A processing unit, wherein the processing unit processes image data output from the camera device.

Images