Photoelectric conversion device, apparatus

Abstract

To increase degree of freedom in element arrangement on a second substrate.SOLUTION: A photoelectric conversion device includes: a first component including a first semiconductor substrate providing a first surface and a second surface, a first photoelectric conversion part, a second photoelectric conversion part, an FD, a first transfer transistor for transferring signal charge generated at the first photoelectric conversion part, and a second transfer transistor for transferring signal charge generated at the second photoelectric conversion part; and a second component including a second semiconductor substrate providing a third surface and a fourth surface, an insulator penetrating the second semiconductor substrate, a first amplification transistor to which a signal is inputted through the first transfer transistor, and a second amplification transistor to which a signal is inputted through the second transfer transistor, the second component being laminated on the first component. A polysilicon member which is the gate of the first transfer transistor is the gate of the second transfer transistor, and a penetration electrode penetrating the insulator and the polysilicon member are electrically connected.SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] The present invention relates to a photoelectric conversion device and an instrument. [Background technology]

[0002] Patent Document 1 describes a photoelectric conversion device configured by stacking three semiconductor substrates. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2018 / 113606 A Summary of the Invention [Problem to be solved by the invention]

[0004] In Patent Document 1, since the through electrodes are provided in the insulating region that penetrates the second substrate, the area of ​​the second substrate on which elements can be arranged is limited. [Means for solving the problem]

[0005] One aspect of the present disclosure relates to a first component including a first semiconductor substrate having a first surface and a second surface facing the first surface, a first photoelectric conversion unit receiving light from the second surface, a second photoelectric conversion unit receiving light from the second surface, a floating diffusion, a first transfer transistor provided on the side of the first surface and transferring a signal charge generated in the first photoelectric conversion unit to the floating diffusion, and a second transfer transistor provided on the side of the first surface and transferring a signal charge generated in the second photoelectric conversion unit to the floating diffusion; a second semiconductor substrate having a fourth surface facing the third surface and the fourth surface, an insulator penetrating the second semiconductor substrate from one of the third surface and the fourth surface to the other, a first amplifying transistor to which a signal is input via the first transfer transistor, and a second amplifying transistor to which a signal is input via the second transfer transistor, and a second component stacked on the first component, wherein a polysilicon member that is the gate of the first transfer transistor is the gate of the second transfer transistor, and a through electrode that penetrates the insulator is electrically connected to the polysilicon member. Effect of the Invention

[0006] According to the present invention, it is possible to improve the degree of freedom in arranging elements on the second substrate. [Brief description of the drawings]

[0007] [Figure 1] FIG. 1 is a diagram showing a configuration of a photoelectric conversion device according to an embodiment. [Diagram 2] 4 is an example of an arrangement of a sensor substrate of a photoelectric conversion device according to an embodiment. [Diagram 3] 4 is an example of the layout of a circuit board of a photoelectric conversion device according to an embodiment. [Figure 4] 1 is a block diagram including an equivalent circuit of a photoelectric conversion element of a photoelectric conversion device according to a first embodiment. [Diagram 5] FIG. 1 is a plan view of a photoelectric conversion device according to a first embodiment. [Figure 6]1 is a cross-sectional view of a photoelectric conversion device according to a first embodiment. [Figure 7] FIG. 11 is a block diagram including an equivalent circuit of a photoelectric conversion element of a photoelectric conversion device according to a second embodiment. [Figure 8] FIG. 4 is a plan view of a photoelectric conversion device according to a second embodiment. [Figure 9] FIG. 4 is a cross-sectional view of a photoelectric conversion device according to a second embodiment. [Figure 10] FIG. 11 is a plan view of a modified example of the photoelectric conversion device according to the second embodiment. [Figure 11] 13 is an equivalent circuit of a photoelectric conversion element of a photoelectric conversion device according to a third embodiment. [Figure 12] FIG. 11 is a plan view of a photoelectric conversion device according to a third embodiment. [Figure 13] FIG. 11 is a cross-sectional view of a photoelectric conversion device according to a third embodiment. [Figure 14] FIG. 13 is a diagram showing a structure of a charge holding unit of a photoelectric conversion device according to a third embodiment. [Figure 15] 13 is a diagram showing a structure of a modified example of the charge holding unit of the photoelectric conversion device according to the third embodiment. FIG. [Figure 16] 13 is a modification of an equivalent circuit of a photoelectric conversion element of the photoelectric conversion device according to the third embodiment. [Figure 17] 13 is a modification of an equivalent circuit of a photoelectric conversion element of the photoelectric conversion device according to the third embodiment. [Figure 18] FIG. 11 is a plan view of a modified example of the photoelectric conversion element of the photoelectric conversion device according to the third embodiment. [Figure 19] FIG. 13 is a diagram illustrating a configuration of a photoelectric conversion device according to a fourth embodiment. [Figure 20] 13 is an example of an arrangement of a sensor substrate in a photoelectric conversion device according to a fourth embodiment. [Figure 21] 13 shows an example of the arrangement of a circuit board 1 in a photoelectric conversion device according to a fourth embodiment. [Figure 22] 13 shows an example of the arrangement of a circuit board 2 in a photoelectric conversion device according to a fourth embodiment. [Diagram 23]13 is an equivalent circuit of a photoelectric conversion element of a photoelectric conversion device according to a fourth embodiment. [Figure 24] FIG. 11 is a plan view of a photoelectric conversion device according to a fourth embodiment. [Diagram 25] FIG. 11 is a cross-sectional view of a photoelectric conversion device according to a fourth embodiment. [Figure 26] FIG. 11 is a cross-sectional view of a modified example of the photoelectric conversion device according to the fourth embodiment. [Figure 27] 13 is a modified equivalent circuit of a photoelectric conversion element of the photoelectric conversion device according to the fourth embodiment. [Figure 28] FIG. 13 is a block diagram including a modified equivalent circuit of a photoelectric conversion element of a photoelectric conversion device according to a fourth embodiment. [Figure 29] FIG. 13 is a plan view of a modified example of the photoelectric conversion device according to the fourth embodiment. [Diagram 30] FIG. 13 is a functional block diagram of a photoelectric conversion system according to a fifth embodiment. [Diagram 31] FIG. 13 is a functional block diagram of a photoelectric conversion system according to a sixth embodiment. [Diagram 32] FIG. 13 is a functional block diagram of a photoelectric conversion system according to a seventh embodiment. [Diagram 33] FIG. 13 is a functional block diagram of a photoelectric conversion system according to an eighth embodiment. [Diagram 34] FIG. 13 is a functional block diagram of a photoelectric conversion system according to a ninth embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] Each embodiment will be described below with reference to the drawings.

[0009] In the following embodiments, an image pickup device will be mainly described as an example of a photoelectric conversion device. However, each embodiment is not limited to an image pickup device, and can be applied to other examples of photoelectric conversion devices. For example, a distance measuring device (a device for measuring distance using focus detection or TOF (Time Of Flight)) or a photometric device (a device for measuring the amount of incident light) may be used.

[0010] In addition, the conductivity types of the semiconductor regions and wells and the dopants to be implanted described in the following embodiments are merely examples and are not limited to the conductivity types and dopants described in the embodiments. The conductivity types and dopants described in the embodiments can be changed as appropriate, and the potentials of the semiconductor regions and wells are changed as appropriate in accordance with this change.

[0011] The conductivity types of the transistors described in the following embodiments are merely examples and are not limited to those described in the examples. The conductivity types described in the embodiments can be changed as appropriate, and the potentials of the gate, source, and drain of the transistors are changed as appropriate.

[0012] For example, in the case of a transistor operated as a switch, the low and high levels of the potential supplied to the gate may be reversed in accordance with the change in the conductivity type, as compared to the description in the embodiment. The conductivity type of the semiconductor region described in the embodiment described below is also merely an example, and is not limited to the conductivity type described in the embodiment. The conductivity type may be changed as appropriate from the conductivity type described in the embodiment, and the potential of the semiconductor region may be changed as appropriate in accordance with this change.

[0013] In the following embodiments, the connection between elements of a circuit may be described. In this case, even if another element is interposed between the elements of interest, the elements of interest are treated as being connected to each other unless otherwise specified. For example, assume that element A is connected to one node of a capacitive element C having multiple nodes, and element B is connected to the other node. Even in such a case, element A and element B are treated as being connected to each other unless otherwise specified.

[0014] Metallic members such as wiring and pads described in this specification may be composed of a single metal element or may be a mixture (alloy). For example, wiring described as copper wiring may be composed of a single copper element or may be composed mainly of copper and further contain other components. Also, for example, pads connected to external terminals may be composed of a single aluminum element or may be composed mainly of aluminum and further contain other components. The copper wiring and aluminum pads shown here are examples and can be changed to various metals.

[0015] Moreover, the wiring and pads shown here are one example of metal members used in a photoelectric conversion device, and the present invention can also be applied to other metal members.

[0016] A configuration common to each embodiment of a photoelectric conversion device, which is an example of a semiconductor device according to the present invention, will be described with reference to FIGS. 1 to 3. FIG.

[0017] FIG. 1 is a diagram showing a configuration of a stacked type photoelectric conversion device 100 according to an embodiment of the present invention. The photoelectric conversion device 100 is configured by stacking and electrically connecting two substrates, a sensor substrate 11 and a circuit substrate 21. The sensor substrate 11 has a first semiconductor layer (first semiconductor substrate) having a photoelectric conversion element 102 described later, and a first wiring layer. The circuit substrate 21 has a second semiconductor layer (second semiconductor substrate) having circuits such as a signal processing unit 103 described later, and a second wiring layer. In the photoelectric conversion device described in each embodiment, the surface of the first semiconductor layer in contact with the first wiring layer is called the first semiconductor layer front surface (first surface), and the surface of the first semiconductor layer 300 facing the first semiconductor layer front surface is called the first semiconductor layer back surface (second surface). Similarly, the surface of the second semiconductor layer 400 in contact with the second wiring layer 401 is called the second semiconductor layer front surface (third surface), and the surface of the second semiconductor layer 400 on the opposite side is called the second semiconductor layer back surface (fourth surface). In the following, the sensor substrate 11 and the circuit substrate 21 are described as diced chips, but are not limited to chips. For example, each substrate may be a wafer. Also, each substrate may be stacked in a wafer state and then diced, or may be chipped and then stacked and bonded.

[0018] A pixel region 12 is disposed on the sensor substrate 11, and a circuit region 22 that processes signals detected in the pixel region 12 is disposed on the circuit substrate 21.

[0019] 2 is a diagram showing an example of the arrangement of the sensor substrate 11. Pixels 101 each having a photoelectric conversion element 102 are arranged in a two-dimensional array in a plan view to form a pixel region 12.

[0020] The pixel 101 is typically a pixel for forming an image, but when used for TOF (Time of Flight), it does not necessarily have to form an image. That is, the pixel 101 may be a pixel for measuring the time when light arrives and the amount of light.

[0021] 3 is a configuration diagram of the circuit board 21. It has a signal processing unit 103 that processes electric charges photoelectrically converted by the photoelectric conversion element 102 in FIG. 2, a readout circuit 112, a control pulse generating unit 115, a horizontal scanning circuit unit 111, a signal line 113, and a vertical scanning circuit unit 110.

[0022] The photoelectric conversion element 102 in FIG. 2 and the signal processing unit 103 in FIG. 3 are electrically connected via connection wiring provided for each pixel.

[0023] The vertical scanning circuit section 110 receives a control pulse supplied from a control pulse generating section 115 and supplies the control pulse to each pixel. The vertical scanning circuit section 110 uses logic circuits such as a shift register and an address decoder.

[0024] The signal output from the photoelectric conversion element 102 of the pixel is processed by a signal processing unit 103. The signal processing unit 103 includes a reset transistor, an amplifying transistor, a memory, and the like, which will be described later.

[0025] The horizontal scanning circuit unit 111 inputs a control pulse for sequentially selecting each column to the signal processing unit 103 in order to read out a signal from each pixel.

[0026] A signal is output to the signal line 113 from the signal processing unit 103 of the pixel selected by the vertical scanning circuit unit 110 for the selected column.

[0027] The signal output to the signal line 113 is output via an output circuit 114 to a recording unit or a signal processing unit outside the photoelectric conversion device 100 .

[0028] In Fig. 2, the photoelectric conversion elements in the pixel region may be arranged one-dimensionally. The effect of the present invention can be obtained even if there is only one pixel, and the case where there is only one pixel is also included in the present invention. The function of the signal processing unit does not necessarily need to be provided for each photoelectric conversion element, and for example, one signal processing unit may be shared by multiple photoelectric conversion elements and signal processing may be performed sequentially.

[0029] 2 and 3, a plurality of signal processing units 103 are arranged in a region overlapping the pixel region 12 in a planar view. A vertical scanning circuit unit 110, a horizontal scanning circuit unit 111, a column circuit 112, an output circuit 114, and a control pulse generating unit 115 are arranged so as to overlap between an end of the sensor substrate 11 and an end of the pixel region 12 in a planar view. In other words, the sensor substrate 11 has the pixel region 12 and a non-pixel region arranged around the pixel region 12, and the vertical scanning circuit unit 110, the horizontal scanning circuit unit 111, the column circuit 112, the output circuit 114, and the control pulse generating unit 115 are arranged in a region overlapping the non-pixel region in a planar view.

[0030] The arrangement of the signal lines 113, the column circuits 112, and the output circuits 114 is not limited to that shown in Fig. 3. For example, the signal lines 113 may be arranged to extend in the row direction, and the column circuits 112 may be arranged at the ends of the signal lines 113.

[0031] The photoelectric conversion device of each embodiment will be described below. The sensor substrate 11 may be called the first substrate or the first component, and the circuit substrate 21 may be called the second substrate or the second component. The back surface side of the first semiconductor layer defined above may be called the light incident surface side.

[0032] (First embodiment) Hereinafter, the embodiment will be described with reference to the drawings. Fig. 4 is an example of a block diagram including the equivalent circuits of Figs.

[0033] 4 shows an example of the configuration of the pixel 101. An example of the photoelectric conversion element 102 and the signal processing unit 103 is shown.

[0034] Each pixel 101 has, for example, a photodiode PD, a transfer transistor TX electrically connected to the photodiode PD, and a floating diffusion (FD). The signal processing unit 103 temporarily holds the charge output from the photodiode PD via the transfer transistor TX in the FD. The FD is connected to an input node of the amplification transistor AMP. The photodiode PD performs photoelectric conversion to generate a charge according to the amount of received light. The cathode of the photodiode PD is electrically connected to the source of the transfer transistor TX, and the anode of the photodiode PD is given a potential to be applied to the well region. That is, it is electrically connected to a reference potential line (for example, a ground potential). In addition, the photodiode PD is provided inside the well region connected to this reference potential line. The drain of the transfer transistor TX is electrically connected to the floating diffusion FD, and the gate of the transfer transistor TX is electrically connected to a pixel drive line. The transfer transistor TX is, for example, a CMOS (Complementary Metal Oxide Semiconductor) transistor.

[0035] The signal processing unit 103 includes, for example, a reset transistor RES, a selection transistor SEL, and an amplification transistor SF. The selection transistor SEL may be omitted as necessary. Also, a transistor FDINC for changing the capacitance value of FD may be further provided in the electrical path between the reset transistor RES and the floating diffusion FD.

[0036] The source of the reset transistor RES (the input terminal of the signal processing unit 103) is electrically connected to the floating diffusion FD. In addition, the drain of the reset transistor RES is electrically connected to a power supply line (SVDD) and the drain of the amplification transistor SF. The gate of the reset transistor RES is electrically connected to a pixel drive line. The source of the amplification transistor SF is electrically connected to the drain of the selection transistor SEL, and the gate of the amplification transistor SF is electrically connected to the source of the reset transistor RES. The source of the selection transistor SEL (the output terminal of the signal processing unit 103) is electrically connected to a pixel output line, and the gate of the selection transistor SEL is electrically connected to the pixel drive line.

[0037] When the transfer transistor TX is turned on, it transfers the charge of the photodiode PD to the floating diffusion FD. The reset transistor RES resets the potential of the floating diffusion FD to a predetermined potential. When the reset transistor RES is turned on, it resets the potential of the floating diffusion FD to the potential of the power supply line (SVDD). The selection transistor SEL controls the output timing of the pixel signal from the signal processing unit 103. The amplification transistor SF generates a signal having a voltage corresponding to the level of the charge held in the floating diffusion FD as the pixel signal. The amplification transistor SF constitutes a source follower type amplifier and outputs a pixel signal having a voltage corresponding to the level of the charge generated in the photodiode PD. When the selection transistor SEL is turned on, the amplification transistor SF amplifies the potential of the floating diffusion FD and outputs a voltage corresponding to the potential to the column signal processing circuit via the pixel output line 2. The reset transistor RES, the amplification transistor SF, and the selection transistor SEL are, for example, CMOS transistors.

[0038] Fig. 5 is a plan view of the photoelectric conversion device according to this embodiment, in which Fig. 5(a) shows a plan view of the first substrate, and Fig. 5(b) shows a plan view of the second substrate.

[0039] FIG. 5(a) shows four pixels 101 arranged in two rows and two columns among the pixels 101 arranged on the first substrate. The photodiodes PD of the four pixels 101 are connected to the respective FDs through one through via 421. Consider a case where, among the four pixels 101 arranged in two rows and two columns, one of the photodiodes PD arranged in the nth row of the pixel array is called a first photoelectric conversion unit, and the other is called a second photoelectric conversion unit. At this time, the signal charge generated in the first photoelectric conversion unit is transferred to the first floating diffusion FD by the first transfer transistor and input to the gate of the first amplification transistor SF. Also, the signal charge generated in the second photoelectric conversion unit is transferred to the second floating diffusion FD by the second transfer transistor and input to the gate of the second amplification transistor SF. DN shown in FIG. 5(a) is a semiconductor region constituting each photodiode PD. The four pixels 101 share the gate of one transfer transistor TX. The gate of the transfer transistor TX is a polysilicon member provided on the first semiconductor layer, and is connected to a through via 421. In other words, this polysilicon member is the gate of the first transfer transistor and also the gate of the second transfer transistor. Also, a well contact is provided in the well region of the first substrate, which supplies a predetermined potential (typically a ground potential) from the second substrate via the through via 421.

[0040] FIG. 6 is a cross-sectional view of a photoelectric conversion device according to this embodiment. This cross-sectional view shows the AA' cross-section of FIG. 5. The first semiconductor region 300 has a photodiode PD. That is, the semiconductor region 300 includes a photoelectric conversion region DN that generates and accumulates signal charges (electrons in this embodiment) in response to incident light. The semiconductor region DN is an N-type impurity region. FIG. 5 shows a configuration in which four pixels 101 are connected to four FDs via one transfer transistor TX. The cross-sectional view of FIG. 6 shows two of the four pixels 101 that appear in one cross-section.

[0041] The transfer gate of the transfer transistor TX controls conduction between the photodiode PD and the floating diffusion FD. The pixel separation section is provided between the multiple pixels 101, and electrically separates the multiple semiconductor regions 101. The pixel separation section 201 may be configured to include an insulating section such as silicon oxide, or may be a semiconductor region that forms a potential barrier. Typically, it is a semiconductor region in which charges of the opposite polarity to the signal charges accumulated by the photodiode PD are the main carriers. A pixel separation layer is provided between the pixel separation section and the photodiode PD. The pixel separation layer plays a role in reducing dark current, particularly when the pixel separation section is provided as an insulating section. The floating diffusion FD and the gate of the amplification transistor SF are connected via a through electrode. The through electrode is mainly composed of a metal such as tungsten or copper. The through electrode is formed by penetrating an insulator 251 that separates the second semiconductor layer 400. The insulator 251 electrically separates the multiple signal processing sections 103 from each other. Moreover, the insulator 251 is provided penetrating from the third surface to the fourth surface of the second semiconductor layer.

[0042] The transfer transistors TX are scanned row-sequentially for the pixels 101 arranged in an array in the pixel region 12. In a photoelectric conversion device having the configuration shown in Figures 5 and 6, charges are simultaneously transferred to FDs connected to the respective PDs in the pixel 101 arranged in the nth row and the pixel arranged in the n+1th row in the pixel array. A separate signal processing unit 103 is provided independently for each FD of each pixel 101, and FD signals of all the pixels 101 are read out via signal lines, column circuits, and output circuits during one scanning period.

[0043] Second embodiment The photoelectric conversion device according to this embodiment will be described with reference to Figures 7 to 10. Descriptions common to the first embodiment will be omitted, and differences from the first embodiment will be mainly described.

[0044] 7 shows an example of the configuration of a pixel 101 of a photoelectric conversion device according to this embodiment. This embodiment differs from the first embodiment in that two photodiodes PD are connected to one signal processing unit 103 via one floating diffusion FD.

[0045] As in the first embodiment, the first substrate is provided with a photodiode PD, a transfer transistor TX, and a floating diffusion FD. The second substrate is provided with elements such as a reset transistor RES and a selection transistor SEL, as well as control lines and signal lines.

[0046] Fig. 8 is a plan view of the photoelectric conversion device according to this embodiment, in which Fig. 8(a) shows a plan view of the first substrate, and Fig. 8(b) shows a plan view of the second substrate.

[0047] 8(a) shows four pixels 101 arranged in two rows and two columns among the pixels 101 arranged on the first substrate. Of the four pixels 101, two pixels 101 arranged in the same row are connected to one FD via a common through via 421. Also, of the four pixels 101, two pixels 101 arranged in the same column share the gate of one transfer transistor TX. Each transfer transistor TX has one through via 421.

[0048] 9 is a cross-sectional view of the photoelectric conversion device according to this embodiment. This cross-sectional view shows the AA″ cross section of FIG.

[0049] The photoelectric conversion device according to this embodiment is characterized in that, among the four pixels 101 arranged in two rows and two columns, the FDs connected to the pixels 101 that do not share the gates of the transfer transistors TX are shared. By combining the sharing of the gates of the transfer transistors TX with the sharing of the floating diffusions FD, it is possible to reduce the number of through electrodes 421 compared to the first embodiment. In addition, by sharing the signal processing unit 103 among multiple pixels 101, it is possible to reduce the number of circuits arranged on the second substrate. Therefore, it is possible to improve noise performance by, for example, increasing the ratio (L / W) of the channel width (W) to the channel length (L) of the amplification transistor SF.

[0050] In the photoelectric conversion device according to the present embodiment, the transfer transistors are controlled in two-row increments in the order of even-numbered columns (m columns) and odd-numbered columns (m+1 columns). First, charges are transferred to each FD simultaneously in the nth and n+1th rows. Specifically, first, the transfer transistors in the even-numbered columns across the nth and n+1th rows are turned on. Then, the signal (n, m) is transferred to the FD in the nth row. At the same time, the signal (n+1, m) is transferred to the FD in the nth row. Since a pixel circuit is provided independently for each FD, the signals of all FDs are read out during one scanning period via the signal line, column circuit, and output circuit. Then, the transfer transistors in the odd-numbered columns across the nth and n+1th rows are turned on. The subsequent flow is the same as the above-mentioned operation. In other words, a first transfer transistor group including the transfer transistors corresponding to the (n, m) pixel 101 and the transfer transistors corresponding to the (n+1, m) pixel 101 is controlled by a first control signal. A second transfer transistor group including a transfer transistor corresponding to the pixel 101 in the (n, m+1) column and a transfer transistor corresponding to the pixel 101 in the (n+1, m+1) column is also controlled by the first control signal. Note that the driving is not limited to this, and for example, sequential scanning in the column direction may be performed. In addition, at this time, the direction in which the transfer transistors included in the first transfer transistor group are arranged (vertical direction) intersects with the direction in which the floating diffusions FD connected to each of the transfer transistors included in the first transfer transistor group are arranged (horizontal direction).

[0051] Fig. 10 is a plan view of a modified example of the photoelectric conversion device according to this embodiment, Fig. 10(a) shows a plan view of the first substrate, and Fig. 10(b) shows a plan view of the second substrate.

[0052] FIG. 10(a) shows four pixels 101 arranged in two rows and two columns among the pixels 101 arranged on the first substrate. Each pixel 101 has two photodiodes PD arranged under one ML. The two photodiodes PD of each pixel 101 are used for image plane phase difference AF (DAF). One of the two photodiodes PD may be light-shielded and used for SAF. Of the four pixels 101, two pixels 101 arranged in the same row are connected to one FD via a common through via 421. Also, of the four pixels 101, two pixels 101 arranged in the same column share the gate of one transfer transistor TX. Each transfer transistor TX has one through via 421.

[0053] Charges are transferred at the same timing as in the structure shown in Fig. 8. However, since each pixel 101 shown in Fig. 10 has two PDs, three readout operations, including reading out of a noise signal (signal N), are performed in one readout period, which differs from the drive of the photoelectric conversion device shown in Fig. 8. If a signal read out from one of the two PDs is signal A and a signal read out from the other is signal B, three operations, signal N read, signal A read, and signal A + signal B read, are performed in one readout period.

[0054] Third embodiment The photoelectric conversion device according to this embodiment will be described with reference to Figures 11 to 18. Descriptions common to the first embodiment will be omitted, and differences from the first embodiment will be mainly described.

[0055] 11 is an example of the configuration of a pixel 101 of a photoelectric conversion device according to this embodiment. This embodiment differs from the first embodiment in that memories C1 and C2 for holding SF output are provided in the rear stage of the amplification transistor SF. The output terminal of the amplification transistor SF is connected to a node having the memory C1 via a transistor GS1 for collectively writing a signal to the memory C1 of a plurality of pixels. The transistor GS1 is connected to the gate of SF1 via the memory C2, and the memory C2 and the transistor GS2 are provided between GS1 and a wiring for supplying a power supply voltage SVDD. The transistor GS2 resets the potential between the memories C2 and SF1 collectively by turning it on.

[0056] A current source transistor BIAS, which functions as a constant current source, is connected between the output terminal of the amplifying transistor SF and the reference potential Vss. When the current source transistor BIAS is made to function as a constant current source, a voltage of a specified level is applied, and when it is not made to function as a constant current source (not used), a low level (0V) is applied. Although a constant current source is not a required component, including a constant current source in the configuration increases the writing speed to the memory.

[0057] In the circuit configuration according to this embodiment, for example, the following driving is assumed.

[0058] First, the reset transistor RES and the transfer transistor TX are turned on to reset the photodiode PD and start accumulating charges. During the charge accumulation period, the reset transistors RES and GS2 are turned on to reset the potentials of the floating diffusion FD, node X, and node Y.

[0059] Next, after the reset settling period, the transfer transistor TX is turned on to transfer the signal from the photodiode PD to the floating diffusion FD. At this time, the transistor GS1 is also turned on. The voltage level of the SF output is written to node X through GS1, and the voltage is also written to node Y by capacitive coupling.

[0060] By operating the selection transistor SEL, the signals of the nodes Y are read out row by row. The read signals are converted into analog signals by the column ADC in the subsequent stage.

[0061] After that, GS2 is turned on to reset node Y, and after GS is turned off, the reset level of node Y is read out.

[0062] Fig. 12 is a plan view of a photoelectric conversion device according to this embodiment, in which Fig. 12(a) shows a plan view of a first substrate and Fig. 12(b) shows a plan view of a second substrate, which correspond to Fig. 5 of the first embodiment.

[0063] 12(b) differs from the photoelectric conversion device shown in FIG. 5 in that a signal processing unit 103 shown in FIG. 12(b) includes elements that configure a circuit after the SF.

[0064] Fig. 13 is a cross-sectional view of the photoelectric conversion device according to this embodiment. This cross-sectional view corresponds to the A-A' cross section in Fig. 12. This differs from the photoelectric conversion device shown in the first embodiment in that a memory unit is provided in the second wiring layer 401. To realize this configuration, two capacitances are required for one signal processing unit 103. In Fig. 13, two memory units are expressed as one block.

[0065] FIG. 14 shows a cross-sectional view of an example of the structure of the memory section. The memory section may be, for example, a MIM (Metal-Insulator-Metal) capacitor. A plurality of capacitor-forming metals are used to form an MIM capacitor. The material of the capacitor-forming metal may be the same as or different from that of the wiring. The capacitor section interlayer film may be an insulator such as SiO or a dielectric. Since the capacitance increases as the dielectric constant of the capacitor section interlayer film increases, a high-k material may be used. Examples of high-k materials include metal oxides such as hafnium oxide (HfO2), zirconium oxide (ZrO2), titanium oxide (TiO2), and aluminum oxide (Al2O3), as well as their silicates or aluminates. The capacitor section interlayer film may include metal nitride oxides such as aluminum oxynitride (AlON), zirconium oxynitride (ZrON), hafnium oxynitride (HfON), lanthanum oxynitride (LaON), and yttrium oxynitride (YON), as well as their silicates or aluminates.

[0066] Fig. 15 shows a cross-sectional view of another example of the memory section structure different from that shown in Fig. 14. In the configuration shown in Fig. 15, a capacitor is formed by capacitance-forming metal 1 standing on a pillar and capacitance-forming metal 2 facing it via a capacitance section interlayer film. Since capacitance can be formed three-dimensionally, the capacitance can be increased. Increasing the memory capacity is advantageous in terms of the reset noise of the memory section and the signal S / N ratio.

[0067] FIG. 16 shows a modified circuit configuration of the pixel 101. The difference from the circuit shown in FIG. 11 is that the memory provided after the amplification transistor SF is divided into two systems. A second transistor SF2 and a second selection transistor SEL2 are also added according to the branching of the memory. The signal charge generated in the photoelectric conversion unit PD is transferred to the floating diffusion FD by the first transfer transistor and input to the gate of the first amplification transistor SF. The source or drain of the first amplification transistor SF is connected to the first signal holding unit C1 and the gate of the third amplification transistor SF1. In addition, the source or drain of the amplification transistor SF is connected to the second signal holding unit C2 and the gate of the fourth amplification transistor SF2.

[0068] In a circuit having this configuration, a method can be adopted in which the N signal and S signal of the floating diffusion FD are stored in each of the memory sections connected in parallel and then read out sequentially.

[0069] In the circuit shown in Figure 11, signal retention is achieved by capacitance division using two capacitors C1 and C2, which causes a problem that the sampling gain becomes 0.5 times in a normal capacitance configuration. When the gain becomes 0.5 times, the signal amplitude resulting from photoelectric conversion is halved, and the signal-to-noise ratio (S / N ratio) of the downstream column amplifier and AD converter decreases, which generally reduces image quality (Image Quality: IQ).

[0070] On the other hand, in the circuit configuration shown in Fig. 16, the sampling gain can be made nearly 1, so image quality is improved compared to the case where the circuit configuration shown in Fig. 11 is adopted. However, in this configuration, since the signal is read out via different paths, that is, the readout path via SF1 and the readout path via SF2, it is not possible to cancel, for example, the characteristic variation between SF1 and SF2, which may cause the fixed pattern noise to worsen. In addition, it is not possible to remove the reset noise component for each charge transfer.

[0071] Figure 17 shows another modified example of the circuit configuration of the pixel 101. The arrangement of the capacitance and transistor gates is different from Figures 11 and 16. In Figure 17, transistors GS1 and GS2 and memories C1 and C2 are alternately connected in series between the output terminal of the amplification transistor SF and the transistor SF1.

[0072] In this configuration, as in the configuration shown in Fig. 11, the S signal and the N signal can be read out by one readout system, so there is no deterioration of fixed pattern noise caused by element characteristics. In addition, the reset noise of memories C1 and C2 can also be eliminated.

[0073] In the circuit configuration according to this embodiment, for example, the following driving is assumed.

[0074] The operation will be explained from the point where the floating diffusion FD, memory C1, and memory C2 are reset. GS1 and GS2 are turned on, and the N signal, which is the reset level, is read out to memory C2.

[0075] The transfer transistor TX is turned on to transfer the charge from the photodiode PD.

[0076] GS1 is turned off and GS2 is turned on, and the S+N signal is read out to memory C1. After the N signal is read out to the downstream CDS circuit, GS2 is turned on and the charge is distributed. By reading S / 2+N out to the CDS circuit and subtracting the N signal from (S / 2+N), it is possible to obtain the S / 2 signal with pixel reset noise removed.

[0077] FIG. 18 is a plan view of a modified example of the first substrate of the photoelectric conversion device according to the present embodiment.

[0078] The gates of the transfer transistors TX shared by every two rows and two columns of the pixels 101 are connected over a wider area as POL wiring. For example, all the pixels in the pixel array may be connected and driven simultaneously. This allows for a further reduction in the number of through electrodes.

[0079] (Fourth embodiment) The photoelectric conversion device according to this embodiment will be described with reference to Fig. 19 to Fig. 29. Descriptions common to the first embodiment will be omitted, and the following will mainly focus on the points different from the third embodiment.

[0080] Fig. 19 is a diagram showing the configuration of a stacked photoelectric conversion device 100 according to an embodiment of the present invention. Fig. 20 is a diagram showing the configuration of a sensor substrate 11. Fig. 21 is a diagram showing the configuration of a circuit substrate 21. Fig. 22 is a diagram showing the configuration of a second circuit substrate 31. The photoelectric conversion device 100 is formed by stacking and electrically connecting three substrates, namely, a sensor substrate 11, a circuit substrate 21, and a second circuit substrate 31. Like the sensor substrate 11 and the circuit substrate 21, the second circuit substrate 31 has a front surface (fifth surface) in contact with the wiring layer and a back surface (sixth surface) opposite the front surface.

[0081] In the following, the sensor substrate 11, the circuit substrate 21, and the second circuit substrate 31 will be described as diced chips, but are not limited to chips. For example, each substrate may be a wafer. Also, each substrate may be stacked in a wafer state and then diced, or may be chipped and then stacked and bonded. Also, the sensor substrate 11 may be called the first substrate 11, the circuit substrate 21 may be called the second substrate 21, and the second circuit substrate 31 may be called the third substrate 31 or the third component.

[0082] The difference from the third embodiment is that a second circuit board 31 and a second circuit area 32 are added. The signal processing unit 103 is disposed across two boards, the circuit board 21 and the second circuit board 31. The signal processing unit disposed on the circuit board 21 is designated as signal processing unit 103A, and the signal processing unit disposed on the second circuit board 31 is designated as signal processing unit 103B. FIG. 23 is an example of a block diagram including an equivalent circuit of elements disposed on the first to third boards. The signal processing unit 103A includes reset transistors RES, FDINC, and an amplification transistor SF. The signal processing unit 103B includes GS1, GS2, SF1, and SEL1.

[0083] The photoelectric conversion element 102 in Fig. 20 and the signal processing unit 103A in Fig. 21 are electrically connected via a connection wiring provided for each pixel. Furthermore, in this embodiment, the signal processing unit 103A in Fig. 21 and the signal processing unit 103B in Fig. 22 are electrically connected via a connection wiring provided for each pixel.

[0084] FIG. 24 is a schematic plan view of the first substrate 11, the second substrate 21, and the third substrate 31. FIG. 25 is a schematic cross-sectional view of the AA′ cross section of FIG. 24. The third substrate 31 includes a third semiconductor layer 500 (third semiconductor substrate) and a third wiring layer 501. As in the first embodiment, the first substrate 11 and the second substrate 21 are connected such that the front surface of the first semiconductor layer faces the rear surface of the second semiconductor layer. The second substrate 21 and the third substrate 31 are connected such that the front surface of the second semiconductor layer faces the front surface of the third semiconductor layer. This connection is made by using a metal bonding (hybrid bonding) technique using, for example, Cu or Au as a bonding portion.

[0085] Normally, when hybrid bonding is used to bond wiring layers facing each other, it is difficult to electrically connect another semiconductor layer on a pixel-by-pixel basis. However, the configuration shown in this embodiment makes it possible to realize a three-layer stack in which the pixels are electrically connected. With a structure in which three semiconductor layers are stacked, the layout area of ​​the signal processing circuit can be expanded, and high functionality can be achieved.

[0086] FIG. 26 is a schematic cross-sectional view of a modification of the photoelectric conversion device according to the present embodiment taken along line AA' of FIG.

[0087] In the photoelectric conversion device shown in Fig. 25, no metal wiring is provided between the first semiconductor layer 300 and the second semiconductor layer 400. However, as shown in Fig. 26, wiring may be disposed in the first wiring layer 301 between the first semiconductor layer 300 and the second semiconductor layer 400, and the transfer transistors TX of the multiple pixels 101 and the elements on the second semiconductor layer 400 may be connected by wiring in the first wiring layer 301. In this case, it is not necessarily necessary to share the gate of the transfer transistor TX between the multiple pixels 101.

[0088] Further modified examples of the configuration of the photoelectric conversion device according to this embodiment are shown using Figs. 27 to 29. Fig. 27 shows a modified configuration of the pixel 101. The circuit configuration differs from that shown in Fig. 23 in that the signal processing unit 103A includes a selection transistor SEL. Fig. 28 is a block diagram of the circuit, and each pixel 101 and signal processing unit 103 correspond to the circuit diagram of Fig. 27. Each of the four pixels 101 is connected to an independent signal processing unit 103A, and the four pixels 101 share wiring between the signal processing unit 103A and the signal processing unit 103B. With such a configuration, the number of metal bonds can be reduced, which is advantageous for miniaturization.

[0089] In order to ensure the function of the global shutter, which transfers signals at the same time, the transfer transistors TX need only operate collectively and transfer the signals to the FD. In other words, the timing at which the transferred SF output is transferred to the memory unit via the GS1 gate does not need to be collectively. The SEL and GS1 gates corresponding to the four pixels 101 a, b, c, and d shown in FIG. 28 can be operated in that order to transfer the signals to the memory unit.

[0090] Fig. 29 is a plan view corresponding to the configuration shown in Fig. 27 and 28. In the second substrate 21 and the third substrate 31, four pixels in two rows and two columns are connected by a common metal bonding.

[0091] Fifth embodiment The photoelectric conversion system according to this embodiment will be described with reference to Fig. 30. Fig. 30 is a block diagram showing a schematic configuration of the photoelectric conversion system according to this embodiment.

[0092] The photoelectric conversion devices described in the first to fourth embodiments are applicable to various photoelectric conversion systems. Examples of the applicable photoelectric conversion systems include digital still cameras, digital camcorders, security cameras, copiers, fax machines, mobile phones, car-mounted cameras, and observation satellites. Camera modules equipped with an optical system such as a lens and an imaging device are also included in the photoelectric conversion systems. FIG. 29 illustrates a block diagram of a digital still camera as an example of these.

[0093] 30 includes an imaging device 1004, which is an example of a photoelectric conversion device, and a lens 1002 that forms an optical image of a subject on the imaging device 1004. The system further includes an aperture 1003 that varies the amount of light passing through the lens 1002, and a barrier 1001 that protects the lens 1002. The lens 1002 and the aperture 1003 form an optical system that focuses light on the imaging device 1004. The imaging device 1004 is a photoelectric conversion device according to any one of the above embodiments, and converts the optical image formed by the lens 1002 into an electrical signal.

[0094] The photoelectric conversion system also has a signal processing unit 1007 which is an image generating unit that generates an image by processing an output signal output from the imaging device 1004. The signal processing unit 1007 performs various corrections and compression as necessary to output image data. The signal processing unit 1007 may be formed on the semiconductor substrate on which the imaging device 1004 is provided, or may be formed on a semiconductor substrate separate from the imaging device 1004.

[0095] The photoelectric conversion system further includes a memory unit 1010 for temporarily storing image data, and an external interface unit (external I / F unit) 1013 for communicating with an external computer or the like. The photoelectric conversion system further includes a recording medium 1012 such as a semiconductor memory for recording or reading out imaging data, and a recording medium control interface unit (recording medium control I / F unit) 1011 for recording or reading out data on the recording medium 1012. The recording medium 1012 may be built into the photoelectric conversion system, or may be removable.

[0096] The photoelectric conversion system further includes an overall control / calculation unit 1009 that performs various calculations and controls the entire digital still camera, and a timing generation unit 1008 that outputs various timing signals to the image capture device 1004 and the signal processing unit 1007. Here, the timing signals and the like may be input from outside, and the photoelectric conversion system only needs to include at least the image capture device 1004 and the signal processing unit 1007 that processes the output signal output from the image capture device 1004.

[0097] The imaging device 1004 outputs an imaging signal to a signal processing unit 1007. The signal processing unit 1007 performs predetermined signal processing on the imaging signal output from the imaging device 1004, and outputs image data. The signal processing unit 1007 generates an image using the imaging signal.

[0098] In this way, according to this embodiment, it is possible to realize a photoelectric conversion system to which the photoelectric conversion device (imaging device) according to any one of the above embodiments is applied.

[0099] Sixth embodiment The photoelectric conversion system and the moving object of this embodiment will be described with reference to Fig. 31. Fig. 31 is a diagram showing the configuration of the photoelectric conversion system and the moving object of this embodiment.

[0100] FIG. 31(a) shows an example of a photoelectric conversion system related to an in-vehicle camera. The photoelectric conversion system 2300 has an imaging device 2310. The imaging device 2310 is the photoelectric conversion device described in any of the above embodiments. The photoelectric conversion system 2300 has an image processing unit 2312 that performs image processing on a plurality of image data acquired by the imaging device 2310, and a parallax acquisition unit 2314 that calculates parallax (phase difference of parallax images) from the plurality of image data acquired by the photoelectric conversion system 2300. The photoelectric conversion system 2300 also has a distance acquisition unit 2316 that calculates a distance to an object based on the calculated parallax, and a collision determination unit 2318 that determines whether or not there is a possibility of collision based on the calculated distance. Here, the parallax acquisition unit 2314 and the distance acquisition unit 2316 are examples of distance information acquisition means that acquire distance information to an object. That is, the distance information is information on the parallax, the defocus amount, the distance to the object, and the like. The collision determination unit 2318 may determine the possibility of a collision using any of these pieces of distance information. The distance information acquisition means may be realized by dedicated hardware, or may be realized by a software module. In addition, it may be realized by a field programmable gate array (FPGA), an application specific integrated circuit (ASIC), or the like, or may be realized by a combination of these.

[0101] The photoelectric conversion system 2300 is connected to a vehicle information acquisition device 2320, and can acquire vehicle information such as vehicle speed, yaw rate, and steering angle. The photoelectric conversion system 2300 is also connected to a control ECU 2330, which is a control unit that outputs a control signal to generate a braking force for the vehicle based on the judgment result of the collision judgment unit 2318. The photoelectric conversion system 2300 is also connected to an alarm device 2340 that issues an alarm to the driver based on the judgment result of the collision judgment unit 2318. For example, when the judgment result of the collision judgment unit 2318 indicates that there is a high possibility of a collision, the control ECU 2330 performs vehicle control to avoid a collision and reduce damage by applying the brakes, releasing the accelerator, suppressing engine output, etc. The alarm device 2340 warns the user by sounding an alarm, displaying alarm information on the screen of a car navigation system, etc., or vibrating the seat belt or steering wheel.

[0102] In this embodiment, the surroundings of the vehicle, for example, the front or rear, are imaged by the photoelectric conversion system 2300. Fig. 31(b) shows the photoelectric conversion system when imaging the area in front of the vehicle (imaging range 2350). A vehicle information acquisition device 2320 sends an instruction to the photoelectric conversion system 2300 or the imaging device 2310. With such a configuration, the accuracy of distance measurement can be further improved.

[0103] Although the above describes an example of control to prevent collision with other vehicles, the present invention can also be applied to control of automatic driving by following other vehicles, control of automatic driving to prevent deviation from lanes, etc. Furthermore, the photoelectric conversion system is not limited to vehicles such as automobiles, but can be applied to moving bodies (moving devices) such as ships, aircraft, and industrial robots. In addition, the present invention can be applied not only to moving bodies, but also to a wide range of devices that use object recognition, such as intelligent transport systems (ITS).

[0104] Seventh embodiment The photoelectric conversion system of this embodiment will be described with reference to Fig. 32. Fig. 32 is a block diagram showing an example of the configuration of a range image sensor which is the photoelectric conversion system of this embodiment.

[0105] 32, the distance image sensor 401 is configured to include an optical system 407, a photoelectric conversion device 408, an image processing circuit 404, a monitor 405, and a memory 406. The distance image sensor 401 can obtain a distance image according to the distance to the subject by receiving light (modulated light or pulsed light) that is projected from a light source device 411 toward the subject and reflected by the surface of the subject.

[0106] The optical system 407 is configured to have one or more lenses, and guides image light (incident light) from a subject to a photoelectric conversion device 408 , forming an image on the light receiving surface (sensor portion) of the photoelectric conversion device 408 .

[0107] As the photoelectric conversion device 408 , the photoelectric conversion device of each of the above-mentioned embodiments is applied, and a distance signal indicating a distance determined from a light reception signal output from the photoelectric conversion device 408 is supplied to the image processing circuit 404 .

[0108] The image processing circuit 404 performs image processing to construct a distance image based on the distance signal supplied from the photoelectric conversion device 408. The distance image (image data) obtained by this image processing is then supplied to a monitor 405 for display, or supplied to a memory 406 for storage (recording).

[0109] In the range image sensor 401 configured in this way, by applying the above-described photoelectric conversion device, it is possible to obtain, for example, a more accurate range image as the pixel characteristics improve.

[0110] Eighth embodiment The photoelectric conversion system of this embodiment will be described with reference to Fig. 33. Fig. 33 is a diagram showing an example of a schematic configuration of an endoscopic surgery system which is the photoelectric conversion system of this embodiment.

[0111] 33 shows a state in which an operator (doctor) 1131 is performing surgery on a patient 1132 on a patient bed 1133 using an endoscopic surgery system 1150. As shown in the figure, the endoscopic surgery system 1150 is composed of an endoscope 1100, a surgical tool 1110, and a cart 1134 on which various devices for endoscopic surgery are mounted.

[0112] The endoscope 1100 is composed of a lens barrel 1101, a region of a predetermined length from the tip of which is inserted into a body cavity of a patient 1132, and a camera head 1102 connected to the base end of the lens barrel 1101. In the illustrated example, the endoscope 1100 is configured as a so-called rigid lens barrel having a rigid lens barrel 1101, but the endoscope 1100 may be configured as a so-called flexible lens barrel having a flexible lens barrel.

[0113] An opening into which an objective lens is fitted is provided at the tip of the lens barrel 1101. A light source device 1203 is connected to the endoscope 1100, and light generated by the light source device 1203 is guided to the tip of the lens barrel 1101 by a light guide extending inside the lens barrel 1101, and is irradiated via the objective lens toward an observation target in a body cavity of a patient 1132. The endoscope 1100 may be a direct-viewing endoscope, an oblique-viewing endoscope, or a side-viewing endoscope.

[0114] An optical system and a photoelectric conversion device are provided inside the camera head 1102, and reflected light (observation light) from an observation target is collected on the photoelectric conversion device by the optical system. The observation light is photoelectrically converted by the photoelectric conversion device to generate an electrical signal corresponding to the observation light, i.e., an image signal corresponding to an observation image. The photoelectric conversion device described in each of the above-mentioned embodiments can be used as the photoelectric conversion device. The image signal is transmitted to a camera control unit (CCU: Camera Control Unit) 1135 as RAW data.

[0115] The CCU 1135 is configured with a CPU (Central Processing Unit), a GPU (Graphics Processing Unit), etc., and performs overall control of the operations of the endoscope 1100 and the display device 1136. Furthermore, the CCU 1135 receives an image signal from the camera head 1102, and performs various types of image processing on the image signal, such as development processing (demosaic processing), for displaying an image based on the image signal.

[0116] Under the control of the CCU 1135 , the display device 1136 displays an image based on an image signal that has been subjected to image processing by the CCU 1135 .

[0117] The light source device 1203 is composed of a light source such as an LED (Light Emitting Diode), and supplies the endoscope 1100 with irradiation light when photographing an operation site or the like.

[0118] The input device 1137 is an input interface for the endoscopic surgery system 1150. A user can input various information and instructions to the endoscopic surgery system 1150 via the input device 1137.

[0119] The treatment tool control device 1138 controls the driving of the energy treatment tool 1112 for cauterizing tissue, incising, sealing blood vessels, or the like.

[0120] The light source device 1203 that supplies irradiation light to the endoscope 1100 when photographing the surgical site can be composed of a white light source composed of, for example, an LED, a laser light source, or a combination of these. When the white light source is composed of a combination of RGB laser light sources, the output intensity and output timing of each color (each wavelength) can be controlled with high precision, so that the white balance of the captured image can be adjusted in the light source device 1203. In this case, it is also possible to capture images corresponding to each of the RGB colors in a time-division manner by irradiating the observation target with laser light from each of the RGB laser light sources in a time-division manner and controlling the driving of the image sensor of the camera head 1102 in synchronization with the irradiation timing. According to this method, a color image can be obtained without providing a color filter to the image sensor.

[0121] Furthermore, the light source device 1203 may be controlled to change the intensity of the light it outputs at predetermined time intervals. By controlling the driving of the image sensor of the camera head 1102 in synchronization with the timing of the change in the light intensity to acquire images in a time-division manner and synthesizing the images, it is possible to generate an image with a high dynamic range that is free of so-called blocked-up shadows and blown-out highlights.

[0122] The light source device 1203 may be configured to supply light in a predetermined wavelength band corresponding to the special light observation. In the special light observation, for example, the wavelength dependency of light absorption in body tissue is utilized. Specifically, a predetermined tissue such as blood vessels on the mucous membrane surface is photographed with high contrast by irradiating light in a narrower band than the irradiation light (i.e., white light) in normal observation. Alternatively, the special light observation may be a fluorescent observation in which an image is obtained by fluorescence generated by irradiating excitation light. In the fluorescent observation, it is possible to irradiate excitation light to the body tissue and observe the fluorescence from the body tissue, or to locally inject a reagent such as indocyanine green (ICG) into the body tissue and irradiate the body tissue with excitation light corresponding to the fluorescent wavelength of the reagent to obtain a fluorescent image. The light source device 1203 may be configured to supply narrow band light and / or excitation light corresponding to such special light observation.

[0123] Ninth embodiment The photoelectric conversion system of this embodiment will be described with reference to Figs. 34(a) and (b). Fig. 34(a) describes glasses 1600 (smart glasses) which are the photoelectric conversion system of this embodiment. The glasses 1600 have a photoelectric conversion device 1602. The photoelectric conversion device 1602 is the photoelectric conversion device described in each of the above embodiments. A display device including a light-emitting device such as an OLED or LED may be provided on the back side of the lens 1601. The photoelectric conversion device 1602 may be one or more. A combination of multiple types of photoelectric conversion devices may also be used. The arrangement position of the photoelectric conversion device 1602 is not limited to that shown in Fig. 34(a).

[0124] The glasses 1600 further include a control device 1603. The control device 1603 functions as a power source that supplies power to the photoelectric conversion device 1602 and the display device. The control device 1603 also controls the operations of the photoelectric conversion device 1602 and the display device. The lens 1601 is formed with an optical system for focusing light on the photoelectric conversion device 1602.

[0125] FIG. 34(b) illustrates glasses 1610 (smart glasses) according to one application example. The glasses 1610 have a control device 1612, and the control device 1612 is equipped with a photoelectric conversion device corresponding to the photoelectric conversion device 1602 and a display device. The lens 1611 is formed with a photoelectric conversion device in the control device 1612 and an optical system for projecting light emitted from the display device, and an image is projected onto the lens 1611. The control device 1612 functions as a power source that supplies power to the photoelectric conversion device and the display device, and controls the operation of the photoelectric conversion device and the display device. The control device may have a line of sight detection unit that detects the line of sight of the wearer. Infrared light may be used for detecting the line of sight. The infrared light emission unit emits infrared light to the eyeball of a user gazing at a display image. An imaging unit having a light receiving element detects the reflected light of the emitted infrared light from the eyeball, thereby obtaining an image of the eyeball. By having a reduction means for reducing light from the infrared light emission unit to the display unit in a planar view, deterioration of image quality is reduced.

[0126] The gaze of the user with respect to the displayed image is detected from an image of the eyeball obtained by capturing infrared light. Any known method can be applied to gaze detection using the image of the eyeball. As an example, a gaze detection method based on a Purkinje image formed by reflection of irradiated light on the cornea can be used.

[0127] More specifically, the gaze detection process is performed based on the pupil-corneal reflex method. Using the pupil-corneal reflex method, a gaze vector that indicates the direction (rotation angle) of the eyeball is calculated based on the pupil image and the Purkinje image included in the captured image of the eyeball, thereby detecting the user's gaze.

[0128] The display device of this embodiment may have a photoelectric conversion device having a light receiving element, and may control the display image of the display device based on information about the user's line of sight from the photoelectric conversion device.

[0129] Specifically, the display device determines a first field of view area to which the user gazes and a second field of view area other than the first field of view area based on the line-of-sight information. The first field of view area and the second field of view area may be determined by a control device of the display device, or may be received from an external control device. In the display area of ​​the display device, the display resolution of the first field of view area may be controlled to be higher than the display resolution of the second field of view area. In other words, the resolution of the second field of view area may be lower than that of the first field of view area.

[0130] The display area may have a first display area and a second display area different from the first display area, and a high priority area may be determined from the first display area and the second display area based on line-of-sight information. The first field of view area and the second field of view area may be determined by a control device of the display device, or may be determined by an external control device and received. The resolution of the high priority area may be controlled to be higher than the resolution of areas other than the high priority area. In other words, the resolution of an area with a relatively low priority may be lowered.

[0131] AI may be used to determine the first field of view area and areas with high priority. The AI ​​may be a model configured to estimate the angle of the line of sight and the distance to an object at the end of the line of sight from the image of the eyeball, using as teacher data an image of the eyeball and the direction in which the eyeball in the image was actually looking. The AI ​​program may be included in the display device, the photoelectric conversion device, or an external device. If included in the external device, it is transmitted to the display device via communication.

[0132] When display control is performed based on visual recognition detection, the present invention is preferably applicable to smart glasses further including a photoelectric conversion device for capturing an image of the outside world. The smart glasses can display captured outside information in real time.

[0133] (Modified embodiment) The present invention is not limited to the above-described embodiment, and various modifications are possible.

[0134] For example, an example in which part of the configuration of any one of the embodiments is added to another embodiment, or an example in which part of the configuration of another embodiment is substituted therefor, is also included in the embodiments of the present invention.

[0135] Further, the photoelectric conversion systems shown in the fifth and sixth embodiments are examples of photoelectric conversion systems to which the photoelectric conversion device can be applied, and the photoelectric conversion systems to which the photoelectric conversion device of the present invention can be applied are not limited to the configurations shown in Fig. 30 to Fig. 31. The same applies to the ToF system shown in the seventh embodiment, the endoscope shown in the eighth embodiment, and the smart glasses shown in the ninth embodiment.

[0136] It should be noted that the above-mentioned embodiments are merely examples of the implementation of the present invention, and the technical scope of the present invention should not be interpreted as being limited by these embodiments. In other words, the present invention can be implemented in various forms without departing from its technical concept or main features. [Explanation of symbols]

[0137] 300 First semiconductor layer 400 Second semiconductor layer 301 1st wiring layer 401 2nd wiring layer 422 Insulation isolation area 421 Through Via

Claims

1. a first component including a first semiconductor substrate having a first surface and a second surface opposite to the first surface, and having a first photoelectric conversion unit that receives light from the second surface, a second photoelectric conversion unit that receives light from the second surface, a floating diffusion, a first transfer transistor that is provided on the side of the first surface and transfers signal charges generated in the first photoelectric conversion unit to the floating diffusion, and a second transfer transistor that is provided on the side of the first surface and transfers signal charges generated in the second photoelectric conversion unit to the floating diffusion; a second semiconductor substrate including a third surface and a fourth surface facing the third surface, an insulator penetrating the second semiconductor substrate from one of the third surface and the fourth surface to the other; a first amplification transistor to which a signal is input via the first transfer transistor; and a second amplification transistor to which a signal is input via the second transfer transistor, the second component being stacked on the first component; A photoelectric conversion device characterized in that the polysilicon member that is the gate of the first transfer transistor is the gate of the second transfer transistor, and a through electrode that penetrates the insulator and the polysilicon member are electrically connected.

2. 2. The photoelectric conversion device according to claim 1, wherein the first transfer transistor and the second transfer transistor are controlled by a common control signal.

3. the floating diffusion includes a first floating diffusion and a second floating diffusion; signal charges generated in the first photoelectric conversion portion are transferred to the first floating diffusion; 3. The photoelectric conversion device according to claim 2, wherein the signal charge generated in the second photoelectric conversion portion is transferred to the second floating diffusion.

4. a source or a drain of the first amplifying transistor is connected to a first signal holding unit and a third amplifying transistor; 4. The photoelectric conversion device according to claim 3, wherein the source or drain of the second amplifying transistor is connected to a second signal holding unit and a fourth amplifying transistor.

5. 4. The photoelectric conversion device according to claim 3, wherein the source or drain of the first amplifying transistor is connected to a first signal holding unit, a second signal holding unit, a third amplifying transistor, and a fourth amplifying transistor.

6. 6. The photoelectric conversion device according to claim 5, wherein the first signal holding unit and the second signal holding unit are connected in parallel.

7. 6. The photoelectric conversion device according to claim 5, wherein the first signal holding unit and the second signal holding unit are connected in series.

8. 5. The photoelectric conversion device according to claim 4, wherein the third amplifying transistor and the fourth amplifying transistor are controlled by different control signals.

9. The photoelectric conversion device according to claim 4, further comprising a third semiconductor substrate having a fifth surface and a sixth surface opposite to the fifth surface, and a third component having the first signal holding unit, the second signal holding unit, the third amplification transistor, and the fourth amplification transistor.

10. the number of joints electrically connecting the first component and the second component is 10. The photoelectric conversion device according to claim 9, wherein the number of the first and second components is smaller than the number of the joints electrically connecting the second and third components.

11. 2. The photoelectric conversion device according to claim 1, wherein the first transfer transistor is supplied with a voltage via the second semiconductor substrate.

12. The photoelectric conversion device according to claim 9 , wherein the first component has a first wiring layer on the first surface.

13. a first transfer transistor group including a plurality of transfer transistors including the first transfer transistor is controlled by a first control signal; 2. The photoelectric conversion device according to claim 1, wherein a second transfer transistor group consisting of a plurality of transfer transistors including the second transfer transistor is controlled by a first control signal.

14. a direction in which the plurality of transfer transistors included in the first transfer transistor group are arranged intersects with a direction in which the plurality of floating diffusions to which the plurality of transfer transistors included in the first transfer transistor group are respectively connected are arranged; 14. The photoelectric conversion device according to claim 13, wherein the number of the floating diffusions is less than the number of the transfer transistors.

15. 15. The photoelectric conversion device according to claim 14, wherein one of the first photoelectric conversion unit and the second photoelectric conversion unit is shielded from light.

16. 14. The photoelectric conversion device according to claim 13, wherein the first transfer transistor is supplied with a voltage via the second semiconductor substrate.

17. The photoelectric conversion device according to claim 13 , wherein the first component has a first wiring layer on the first surface.

18. The photoelectric conversion device according to any one of claims 1 to 17, a signal processing unit that generates an image using a signal output from the photoelectric conversion device.

19. A moving object comprising the photoelectric conversion device according to any one of claims 1 to 17, a control unit that controls the movement of the moving body using a signal output from the photoelectric conversion device; A moving object characterized by:

Images