Photoelectric conversion device, photoelectric conversion system, and moving object

Abstract

The invention provides a photoelectric conversion device, a photoelectric conversion system, and a moving object. The photoelectric conversion device includes: an avalanche photodiode having a first terminal and a second terminal; a first power source connected to the first terminal; a second power supply connected to the second terminal; a charging unit configured to control a voltage of the first terminal; a voltage control unit connected to the first terminal and configured to control a voltage of the first terminal according to the voltage of the first terminal; and the third power supply is connected with the voltage control unit.

Description

Technical Field

[0001] The present disclosure relates to a photoelectric conversion device, a photoelectric conversion system including the photoelectric conversion device, and a moving body including the photoelectric conversion device. Background Art

[0002] A photoelectric conversion device configured with a pixel including a plurality of avalanche photodiodes (hereinafter referred to as APDs) is known. Single-photon level light detection in each pixel is performed using avalanche multiplication caused by photocharges generated by the incidence of photons on the APDs.

[0003] Japanese Patent Laid-Open No. 2020-123847 discusses a light detection device having a charging unit between a cathode of an APD and a supply line of a power supply voltage to switch a state between a charging state and a standby state waiting for incidence of photons.

[0004] In Japanese Patent Laid-Open No. 2020-123847, sufficient consideration has not been given to a phenomenon occurring in a standby state in which the charging unit and the power source are disconnected. Summary of the invention

[0005] According to aspects of the present disclosure, a photoelectric conversion device includes: an avalanche photodiode having a first terminal and a second terminal; a first power supply connected to the first terminal; a second power supply connected to the second terminal; a charging unit configured to control the voltage of the first terminal; a voltage control unit connected to the first terminal and configured to control the voltage of the first terminal according to the voltage of the first terminal; and a third power supply connected to the voltage control unit.

[0006] The present disclosure is directed to providing a photoelectric conversion device that solves a problem that occurs in a standby state in which a charging unit and a power source are disconnected.

[0007] Further features of the present invention will become apparent from the following description of exemplary embodiments with reference to the attached drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Figure 1 is a diagram showing a configuration of a photoelectric conversion device according to an embodiment.

[0009] Figure 2 is a diagram showing the arrangement of a sensor substrate of a photoelectric conversion device according to the embodiment.

[0010] Figure 3 is a diagram showing a configuration of a circuit substrate of a photoelectric conversion device according to the embodiment.

[0011] Figure 4 is a block diagram illustrating one pixel of a sensor substrate and a circuit substrate according to an example of the embodiment.

[0012] Figure 5 (A) to (C) are schematic diagrams illustrating driving of a pixel circuit of a photoelectric conversion device according to the embodiment.

[0013] Figure 6 A configuration example of a pixel circuit of the photoelectric conversion device according to the first embodiment is shown.

[0014] Figure 7 is a diagram showing the relationship among a clock signal, photon entry timing, a voltage of a cathode terminal, and a current flowing through a voltage control unit according to the example and the first embodiment.

[0015] Figure 8 is a graph showing the relationship between the reverse current and the cathode voltage according to the example and the first embodiment.

[0016] Fig. 9 is a configuration diagram of a pixel circuit of a photoelectric conversion device according to a first example.

[0017] Fig.10 is a configuration diagram of a pixel circuit of a photoelectric conversion device according to a second example.

[0018] Fig.11 is a configuration diagram of a pixel circuit of a photoelectric conversion device according to a third example.

[0019] Fig. 12A and Fig. 12B is a diagram illustrating a problem due to a leakage current according to the third example.

[0020] Fig.13 is a schematic plan view showing the configuration of a charging unit, a waveform shaping unit, and a voltage control unit according to a third example.

[0021] Fig.14 is along Fig.13 Schematic cross-sectional view taken along line XX' in FIG.

[0022] FIG. 15A to FIG. 15C are schematic plan views each showing a wiring layer included in the second wiring structure.

[0023] Fig.16 is a configuration diagram of a pixel circuit of a photoelectric conversion device according to a fourth example.

[0024] Fig.17 is a configuration diagram of a pixel circuit of a photoelectric conversion device according to a fifth example.

[0025] Fig.18 is a diagram showing the relationship among a clock signal, photon entry timing, the voltage of the cathode terminal, and the voltage at the node A according to the fifth example.

[0026] Fig.19 is a schematic plan view showing the configuration of an amplitude conversion unit and a voltage control unit according to a fifth example.

[0027] Fig. 20 is along Fig.19 Schematic cross-sectional view taken along line XX' in FIG.

[0028] Fig.21 is a configuration diagram of a pixel circuit of a photoelectric conversion device according to a sixth example.

[0029] Fig. 22 is a configuration diagram of a pixel circuit of a photoelectric conversion device according to a seventh example.

[0030] Fig.23 is a block diagram showing one pixel of a sensor substrate, a first circuit substrate, and a second circuit substrate of a photoelectric conversion device according to a second embodiment.

[0031] Fig.24 is a functional block diagram of a photoelectric conversion system according to the third embodiment.

[0032] Fig.25A is a diagram showing a photoelectric conversion system according to a fourth embodiment, and Fig.25B It is a diagram showing the configuration of a moving object.

[0033] Fig.26 is a functional block diagram showing a photoelectric conversion system according to the fifth embodiment.

[0034] Fig. 27 is a functional block diagram showing a photoelectric conversion system according to a sixth embodiment.

[0035] Fig.28A and Fig.28B is a diagram showing glasses (smart glasses) as an example of the photoelectric conversion system according to the seventh embodiment.

[0036] Fig.29A and Fig.29B is a diagram showing an example of an electronic device in which a photoelectric conversion apparatus according to an eighth embodiment is mounted.

[0037] Fig.30 is a functional block diagram of a photoelectric conversion system according to a ninth embodiment.

[0038] FIG. 31A to FIG. 31C is a functional block diagram of a photoelectric conversion system according to a tenth embodiment. DETAILED DESCRIPTION

[0039] The embodiments described below are intended to embody the technical concept of the present invention and how to implement it, and should be considered not to limit the present invention. For the purpose of clear description, the size and positional relationship of the components shown in the drawings may be exaggerated. In the following description, the same components are represented by the same reference numerals, and redundant descriptions may be omitted.

[0040] In the following description, terms indicating specific directions and positions (for example, "up", "down", "right", "left", and other terms including these terms) are used as needed, and these terms are used to facilitate understanding of the embodiments with reference to the accompanying drawings, and the technical scope of the present invention is not limited by the meanings of these terms.

[0041] In the specification, a plan view refers to a view in a direction perpendicular to the light incident surface of the semiconductor layer. A cross-sectional view refers to a view from a surface in a direction perpendicular to the light incident surface. When the light incident surface of the semiconductor layer is a rough surface when viewed microscopically, the plan view is defined based on the light incident surface of the semiconductor layer when viewed macroscopically.

[0042] In the following description, the anode of the avalanche photodiode (APD) is at a fixed potential, and a signal is extracted from the cathode side. Thus, a semiconductor region of the first conductivity type in which charges having the same polarity as the signal charge are majority carriers is an N-type semiconductor region, and a semiconductor region of the second conductivity type in which charges having a polarity different from the signal charge are majority carriers is a P-type semiconductor region.

[0043] The present invention is also valid even when the cathode of the APD is at a fixed potential and a signal is extracted from the anode side. In this case, the semiconductor region of the first conductivity type in which the charge having the same polarity as the signal charge is the majority carrier is a P-type semiconductor region, and the semiconductor region of the second conductivity type in which the charge having a polarity different from the signal charge is the majority carrier is an N-type semiconductor region. Although a description is given below of a case in which one of the nodes of the APD is at a fixed potential, the potentials of the two nodes may be variable.

[0044] In this specification, the term "impurity concentration" means the net impurity concentration obtained by subtracting the compensation by the impurity of the opposite conductivity type. That is, "impurity concentration" refers to the net doping concentration. A region where the P-type added impurity concentration is higher than the N-type added impurity concentration is a P-type semiconductor region. Conversely, a region where the N-type added impurity concentration is higher than the P-type added impurity concentration is an N-type semiconductor region.

[0045] In the following embodiments, the connection between the elements of the circuit may be described, and even when another element is interposed between the elements of interest, the elements of interest are considered to be connected to each other unless otherwise specified. For example, element A is connected to one node of a capacitor C having a plurality of nodes, and element B is connected to a different node of capacitor C. Even in such a case, elements A and B are considered to be connected to each other unless otherwise specified.

[0046] Figure 1 is a diagram showing the configuration of a stacked photoelectric conversion device 100. The photoelectric conversion device 100 includes two substrates stacked on each other and electrically connected to each other. The sensor substrate 11 includes a first semiconductor layer and a first wiring structure, wherein the first semiconductor layer includes a photoelectric conversion unit 102 to be described below. The circuit substrate 21 includes a second semiconductor layer and a second wiring structure, wherein the second semiconductor layer includes a circuit such as a signal processing unit 103 to be described below. The second semiconductor layer, the second wiring structure, the first wiring structure, and the first semiconductor layer included in the photoelectric conversion device 100 are stacked in this order. The photoelectric conversion device to be described in each embodiment is a back-illuminated photoelectric conversion device in which light enters from the second side of the first semiconductor layer and the circuit substrate is arranged on the first side of the first semiconductor layer.

[0047] Hereinafter, the sensor substrate 11 and the circuit substrate 21 will be described as a singulated chip, but the sensor substrate 11 and the circuit substrate 21 are not limited to chips. For example, each substrate may be a wafer. Each substrate may be singulated after being stacked in a wafer state, or may be singulated into chips from a wafer state and then joined by stacking chips.

[0048] The pixel region 12 is on the sensor substrate 11 , and the circuit region 22 that processes a signal detected in the pixel region 12 is on the circuit substrate 21 .

[0049] Figure 2 is a diagram showing an arrangement example of the sensor substrate 11. Pixels 101 each including a photoelectric conversion unit 102 including an APD are arranged in a two-dimensional array in a plan view, and form a pixel region 12.

[0050] Typically, the pixel 101 is a pixel for forming an image. In the case where the pixel 101 is used for a time-of-flight (TOF) sensor, an image may not be formed. In other words, the pixel 101 may be a pixel for measuring light arrival time and for measuring light quantity.

[0051] Figure 3 is a configuration diagram of the circuit substrate 21. The circuit substrate 21 includes a circuit for processing Figure 2The photoelectric conversion unit 102 shown includes a signal processing unit 103 for outputting the signal, 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 .

[0052] Figure 2 The photoelectric conversion unit 102 and Figure 3 The illustrated signal processing units 103 are electrically connected to each other via connection lines arranged in the respective pixels.

[0053] The vertical scanning circuit unit 110 receives the control pulse supplied from the control pulse generating unit 115 and supplies the control pulse to each pixel. A logic circuit such as a shift register or an address decoder is used as the vertical scanning circuit unit 110 .

[0054] A signal output from the photoelectric conversion unit 102 of the pixel is processed by the signal processing unit 103. A counter and a memory are configured in the signal processing unit 103, and a digital value is stored in the memory.

[0055] The horizontal scanning circuit unit 111 inputs a control pulse for sequentially selecting each column to the signal processing unit 103 to read out a signal from a memory of each pixel storing a digital signal.

[0056] A signal is output from the signal processing unit 103 of the pixel that has been selected by the vertical scanning circuit unit 110 to the signal line 113 on the selected column.

[0057] The signal output to the signal line 113 is output to a recording unit or a signal processing unit arranged outside the photoelectric conversion device 100 via an output circuit 114 .

[0058] exist Figure 2 In the embodiment, the photoelectric conversion units in the pixel area can be arranged one-dimensionally.

[0059] The function of the signal processing unit may not be included in each of the photoelectric conversion units of all the photoelectric conversion units. For example, one signal processing unit may be shared by a plurality of photoelectric conversion units, and signal processing may be performed sequentially.

[0060] like Figure 2 and Figure 3As shown, a plurality of signal processing units 103 are arranged in a region overlapping with the pixel region 12 in a plan view. The vertical scanning circuit unit 110, the horizontal scanning circuit unit 111, the readout circuit 112, the output circuit 114, and the control pulse generating unit 115 are arranged in such a manner that a region defined by an end of the sensor substrate 11 and an end of the pixel region 12 in a plan view overlaps. In other words, the sensor substrate 11 includes the pixel region 12 and a non-pixel region arranged around the pixel region 12. The vertical scanning circuit unit 110, the horizontal scanning circuit unit 111, the readout circuit 112, the output circuit 114, and the control pulse generating unit 115 are arranged in a region overlapping with the non-pixel region in a plan view.

[0061] Figure 4 Shown including Figure 2 and Figure 3 An example of a block diagram of an equivalent circuit of a pixel is shown. Figure 4 is a block diagram showing a pixel including a general APD.

[0062] exist Figure 4 In the embodiment of the present invention, the photoelectric conversion unit 102 including the APD 201 is arranged on the sensor substrate 11 , and other components are arranged on the circuit substrate 21 .

[0063] The APD 201 generates charge pairs corresponding to incident light through photoelectric conversion. The APD 201 includes a first terminal and a second terminal, a first power source is connected to the first terminal, and a second power source is connected to the second terminal. Figure 4 In the embodiment, the first terminal of the APD 201 is a cathode, and the second terminal is an anode. A voltage VL is supplied from a second power supply to the anode of the APD 201. A voltage VH higher than the voltage VL supplied to the anode is supplied from a first power supply to the cathode of the APD 201. A reverse bias voltage for causing the APD 201 to perform an avalanche multiplication operation is supplied to the anode and cathode of the APD 201. In a state where such a voltage is supplied, the charge generated by the incident light causes avalanche multiplication, and an avalanche current is generated.

[0064] When a reverse bias voltage is supplied, the APD operates in Geiger mode or linear mode. In Geiger mode, the APD operates with an anode-cathode potential difference greater than the breakdown voltage. In linear mode, the APD operates with an anode-cathode potential difference close to the breakdown voltage or with a voltage difference equal to or less than the breakdown voltage.

[0065] An APD operating in the Geiger mode will be referred to as a single-photon avalanche photodiode (SPAD). For example, the voltage VL is -30 V, and the voltage VH is 1 V to 3 V. The APD 201 may operate in the linear mode, or may operate in the Geiger mode.

[0066] The quenching element 202 serving as a charging unit is connected to the APD 201 and a power source for supplying a voltage VH. The quenching element 202 serves as a load circuit (quenching circuit) when a signal is multiplied by avalanche multiplication, and has a function for suppressing avalanche multiplication by lowering a voltage to be supplied to the APD 201 (quenching operation). The quenching element 202 also has a function for returning the voltage to be supplied to the APD 201 to the voltage VH by flowing a current of an amount corresponding to the voltage drop caused by the quenching operation (recharging operation). In this way, the charging unit has a function for controlling the voltage of the APD 201.

[0067] The signal processing unit 103 includes a waveform shaping unit 210 , a counter circuit 211 , and a selection circuit 212 .

[0068] In this specification, the signal processing unit 103 is not particularly limited as long as the signal processing unit 103 includes any one of the waveform shaping unit 210 , the counter circuit 211 , and the selection circuit 212 .

[0069] The waveform shaping unit 210 shapes the potential change of the cathode of the APD 201 obtained at the time of photon detection and outputs a pulse signal. For example, an inverter circuit is used as the waveform shaping unit 210. Figure 4 An example in which one inverter is used as the waveform shaping unit 210 is shown, but a circuit in which a plurality of inverters are connected in series may be used, or other circuits having a waveform shaping effect may be used.

[0070] The counter circuit 211 counts the number (number of times) of pulse signals output from the waveform shaping unit 210 and stores the count value. When the control pulse pRES is supplied via the driving line 213, the number of pulse signals stored in the counter circuit 211 is reset.

[0071] via Figure 4 The drive line 214 ( Figure 3 ), from Figure 3 The vertical scanning circuit unit 110 shown supplies a control pulse pSEL to the selection circuit 212, and switches electrical connection and separation between the counter circuit 211 and the signal line 113. For example, the selection circuit 212 includes a buffer circuit for outputting a signal.

[0072] The electrical connection can be switched by a switch such as a transistor arranged between the quenching element 202 and the APD 201 or between the photoelectric conversion unit 102 and the signal processing unit 103. Similarly, the supply of the voltage VH or the voltage VL to be supplied to the photoelectric conversion unit 102 can be electrically switched using a switch such as a transistor.

[0073] In the present embodiment, a configuration using the counter circuit 211 is described. Alternatively, the photoelectric conversion device 100 may acquire the pulse detection timing by using a time-to-digital converter (hereinafter, TDC) and a memory instead of the counter circuit 211. In this case, the generation timing of the pulse signal output from the waveform shaping unit 210 is converted into a digital signal by the TDC. In order to measure the timing of the pulse signal, the pulse detection timing is obtained from the TDC. Figure 1 The vertical scanning circuit unit 110 shown supplies a control pulse pREF (reference signal) to the TDC via a driving line. Based on the control pulse pREF, the TDC acquires a digital signal indicating the input timing of a signal output from each pixel via the waveform shaping unit 210 as a relative time.

[0074] Figure 5 (A) to (C) are diagrams schematically showing the relationship between the operation of the APD and the output signal.

[0075] Figure 5 (A) is extracted from Figure 4 FIG. 2 shows an APD 201, a quenching element 202, and a waveform shaping unit 210. Figure 5 In (A), the input side of the waveform shaping unit 210 is regarded as VC and the output side is regarded as VO. Figure 5 (B) shows Figure 5 The waveform at VC in (A) changes, and Figure 5 (C) shows Figure 5 The waveform changes at VO in (A).

[0076] During the period from time t0 to time t1, the potential difference VH-VL is applied to Figure 5 APD 201 in (A). In response to a photon entering the APD 201 at time t1, avalanche multiplication occurs in the APD 201, an avalanche multiplication current flows to the quenching element 202, and the voltage at VC drops. After the voltage drop amount further increases and the potential difference applied to the APD 201 decreases, the avalanche multiplication of the APD 201 stops at time t2. During the period from time t2 to time t3, a current compensating for the voltage drop from the voltage VL flows to VC, and the potential level at VC is statically stabilized at the original potential level at time t3. In this process, the output waveform portion exceeding a certain threshold at VC is waveform-shaped by the waveform shaping unit 210 and output as a signal at VO.

[0077] The arrangement of the signal line 113 and the arrangement of the readout circuit 112 and the output circuit 114 are not limited to Figure 3 For example, the signal line 113 may extend in the row direction, and the readout circuit 112 may be arranged at the extended end of the signal line 113 .

[0078] Reference Figures 6 to 8 A photoelectric conversion apparatus according to a first embodiment is described.

[0079] Figure 6 A photoelectric conversion unit 102 including an APD 201 having a cathode (first terminal) and an anode (second terminal) and a portion of a signal processing unit 703 are shown. The cathode of the APD 201 is connected to a first power source 601 via a quenching element 202 serving as a charging unit. A waveform shaping unit 210 is connected to the cathode of the APD 201. The cathode of the APD 201 is connected to a third power source 603 via a voltage control unit (limiting unit) 604. The voltage control unit 604 controls the voltage of the cathode according to the voltage of the cathode.

[0080] For example, when the voltage of the cathode drops to a predetermined value, the voltage control unit 604 controls the voltage of the cathode to reduce the drop in the voltage of the cathode. Figure 6 , the voltage of the first power supply 601 is represented by VH, the voltage of the second power supply 602 is represented by VL, and the voltage of the third power supply 603 is represented by GND. The voltage GND of the third power supply 603 is a voltage value between the voltage VH of the first power supply 601 and the voltage VL of the second power supply 602. Specifically, the voltage VH of the first power supply 601 is, for example, 1.1V, the voltage VL of the second power supply 602 is, for example, -30V, and the voltage GND of the third power supply 603 is, for example, 0V. The voltage GND of the third power supply 603 may be equal to the voltage VH of the first power supply 601. In this case, the voltage VH of the first power supply 601 is, for example, 1.1V, the voltage VL of the second power supply 602 is, for example, -30V, and the voltage GND of the third power supply 603 is, for example, 1.1V.

[0081] The quenching element 202 includes, for example, a P-channel metal oxide semiconductor (PMOS) transistor, and the clock signal PCLKB is input to the gate of the PMOS transistor. For example, the clock signal PCLKB is input at a predetermined cycle. In the present embodiment, the presence or absence of electrical connection between the first power source 601 and the cathode of the APD 201 is switched by controlling the on / off of the quenching element 202 according to the clock signal PCLKB input to the quenching element 202.

[0082] One terminal of the voltage control unit 604 is connected to the cathode of the APD 201, and the other terminal is connected to the third power supply 603. The voltage control unit 604 is connected to the cathode of the APD 201, and controls the cathode voltage VC of the APD 201. In response to the cathode voltage VC reaching a predetermined voltage, current flows from the third power supply 603 to VC. Figure 6In FIG. 6 , the voltage control unit 604 is connected to the cathode side of the APD 201 , but as described below, the voltage control unit 604 may be connected to the anode side of the APD 201 .

[0083] Figure 7 is a diagram showing the relationship between the clock signal PCLKB, the photon entry timing, the cathode voltage VC, and the current flowing through the voltage control unit 604. When the clock signal PCLKB becomes a low level at time t1, the PMOS transistor of the quenching element 202 is turned on, and the cathode voltage VC is charged from the potential V1 to the potential V2. The potential V2 corresponds to the voltage VH which is the voltage value of the first power supply 601. In this process, the voltage difference applied between the anode and the cathode of the APD 201 is Vbd (breakdown voltage) + Vex (overvoltage). In this state, the voltage applied to the APD 201 is a voltage to which Vex is excessively applied relative to the breakdown voltage, and avalanche multiplication can be performed in the Geiger mode.

[0084] Then, when the clock signal PCLKB changes to a high level, the PMOS transistor of the quenching element 202 is turned off, and the node connected to the cathode terminal of the APD 201 enters a floating state.

[0085] In response to the photon entering at time t2, avalanche multiplication occurs in the APD 201, and the cathode voltage VC drops from the potential V2 to the potential V1. The potential V1 is a value that is less than the potential V2 by Vex, and at this time, the reverse bias voltage of the APD 201 drops to a voltage that is less than the breakdown voltage. The potential V2 is the voltage VH of the first power supply 601, and as described above, the voltage VH is Vbd+Vex. Thus, even when the cathode voltage VC drops to the potential V1 due to the occurrence of avalanche multiplication, the voltage difference to be applied to the APD 201 can be maintained to be a voltage difference equal to or greater than the breakdown voltage.

[0086] When the cathode voltage VC drops to a voltage lower than the potential V1 , the voltage difference to be applied to the APD 201 drops to a voltage difference lower than the breakdown voltage.

[0087] Then, in response to the photon entering at or after time t2, since a reverse bias voltage less than the breakdown voltage is applied to the APD 201, avalanche multiplication in the Geiger mode does not occur. On the other hand, a reverse bias voltage is applied to the APD 201 between the first power supply 601 and the second power supply 602, electron-hole pairs are generated by light emission, and a reverse current is generated. For this reason, in the absence of the voltage control unit 604, as Figure 7As shown by the dotted line in , the cathode voltage VC continues to drop to a potential lower than the potential V1. When the clock signal PCLKB becomes a low level again at time t4, the APD 201 is recharged, and the cathode voltage of the APD 201 also returns to the potential V2.

[0088] Figure 8 : is a graph showing the relationship between the magnitude of the reverse current generated after avalanche multiplication and the cathode voltage VC. Figure 8 As shown in FIG. 1 , when the reverse current flows, the cathode voltage VC decreases. In the absence of the voltage control unit 604, since the cathode voltage VC decreases until the clock signal PCLKB becomes a low level, Figure 8 As shown by the dotted line in , the cathode voltage VC may exceed the withstand voltage of the MOS transistor.

[0089] In view of the above situation, in this embodiment, if Figure 6 As shown, a voltage control unit 604 is provided. Even in the case of the voltage control unit 604, the cathode voltage VC still drops due to the light emitted after the avalanche multiplication. Figure 7 As shown, when the cathode voltage VC drops to a predetermined value at time t3, the voltage control unit 604 controls the third power supply 603 to cause current to flow to the cathode of the APD 201. This can prevent the cathode voltage VC from dropping to a value exceeding the predetermined value. This can prevent the cathode voltage VC from exceeding the withstand voltage of the MOS transistor, and can provide a photoelectric conversion device with high stability.

[0090] (First example)

[0091] Reference Fig. 9 A first example included in the above-mentioned first embodiment is described. Fig. 9 The photoelectric conversion unit 102 and a part of the signal processing unit 903 are shown. In this example, the voltage control unit 604 includes a PMOS transistor 905.

[0092] The source of the PMOS transistor 905 is connected to the third power supply 603, and the drain of the PMOS transistor 905 is connected to the cathode of the APD 201. The drain of the PMOS transistor 905 is connected to the gate of the PMOS transistor 905. Due to the photocurrent generated after the avalanche multiplication, the cathode voltage VC drops, and when the cathode voltage VC drops to a threshold value that causes the PMOS transistor 905 to enter the on state, the current from the third power supply 603 flows to the cathode of the APD 201. Because the cathode voltage VC can be increased by this current, the cathode voltage VC is prevented from dropping to a value exceeding a predetermined value, and the cathode voltage VC is prevented from exceeding the withstand voltage of the MOS transistor included in the quenching element 202. With this configuration, a photoelectric conversion device with high stability can be provided. Since the voltage control unit 604 can be implemented by a single PMOS transistor, the area occupation can be reduced.

[0093] The PMOS transistor 905 has a higher withstand voltage than the withstand voltage of the MOS transistor included in the quenching element 202. For example, the film thickness of the gate oxide film of the PMOS transistor 905 is thicker than the film thickness of the gate oxide film of the MOS transistor included in the quenching element 202. With this configuration, the withstand voltage is made higher. From the aspect of miniaturization, the withstand voltage of the MOS transistor included in the quenching element 202 can be fixed at a constant value or lower. On the other hand, because the PMOS transistor 905 can be designed relatively freely, the withstand voltage of the PMOS transistor 905 can be made higher.

[0094] (Second example)

[0095] Reference Fig.10 A second example included in the above-mentioned first embodiment is described. Fig.10 The photoelectric conversion unit 102 and part of the signal processing unit 1503 are shown.

[0096] In this example, the voltage control unit 604 includes a diode 1006. The anode of the diode 1006 is connected to the third power supply 603, and the cathode of the diode 1006 is connected to the cathode of the APD 201. Due to the photocurrent generated after avalanche multiplication, the cathode voltage VC drops. For example, in response to the cathode voltage VC dropping to a voltage equal to or less than the voltage of the third power supply 603, a forward bias voltage is applied to the diode to which the reverse bias voltage has been applied, which causes a current to flow from the third power supply 603 to the cathode of the APD 201 via the diode 1006. Because the cathode voltage VC is increased by this current, the cathode voltage VC is prevented from dropping to a value exceeding a predetermined value, which prevents the withstand voltage of the MOS transistor from being exceeded. With this configuration, a photoelectric conversion device with high stability can be provided.

[0097] (Third Example)

[0098] Reference Fig.11 A third example included in the first embodiment is described. Fig.11 The photoelectric conversion unit 102 and part of the signal processing unit 1103 are shown.

[0099] In this example, the voltage control unit 604 includes a diode 1106 and a PMOS transistor 1105. The anode of the diode 1106 is connected to the third power supply 603, and the cathode of the diode 1106 is connected to the source of the PMOS transistor 1105. The drain of the PMOS transistor 1105 is connected to the cathode of the APD 201. The drain of the PMOS transistor 1105 is connected to the gate of the PMOS transistor 1105. Due to the photocurrent generated after the avalanche multiplication, the cathode voltage VC drops, and the PMOS transistor 1105 enters the on state. Because the forward bias voltage is applied to the diode 1106 by the voltage of the third power supply 603 and the voltage of the cathode of the APD 201, the current flows from the third power supply 603 to the cathode of the APD 201. By this current, the cathode voltage VC increases, and the cathode voltage VC is prevented from dropping to a value exceeding a predetermined value, which prevents the withstand voltage of the MOS transistor included in the quenching element 202 from being exceeded. A photoelectric conversion device with high stability can be provided.

[0100] Generally, the leakage current of a MOS transistor is higher than the leakage current of a diode. For this reason, when a MOS transistor and a diode are used in combination, the leakage current generated in the current flow from the third power supply 603 to the cathode of the APD 201 is reduced compared to the case where a single PMOS transistor is configured corresponding to the first example. Fig. 12A and Fig. 12B Describe the problems that occur when leakage current is high.

[0101] Fig. 12Ais a diagram showing a case where a photon is detected immediately after recharging. In response to the clock signal PCLKB becoming a low level at time t1, the PMOS transistor used as the quenching element 202 enters a conductive state, the cathode voltage VC rises due to recharging, and the cathode voltage VC reaches a voltage value of the voltage V2 (e.g., 1.1V). In response to the photon entering at time t2, the cathode voltage VC drops to a voltage value of the voltage V1 (e.g., -1.4V in the case where Vex is 2.5V). Since the leakage current is high in the case of a single PMOS transistor, current flows from the third power supply 603 to the cathode of the APD 201. In the case where the cathode voltage VC after avalanche multiplication is a negative value (e.g., -1.4V), the voltage increases toward the positive direction, a reverse bias voltage equal to or greater than the breakdown voltage is applied to the APD 201, and the voltage reaches a voltage at which avalanche multiplication may occur. In this way, under high illumination, photons can be detected multiple times during the period from time t1 to time t3 when the clock signal PCLKB becomes low again, which creates a problem of increased power consumption. On the other hand, by using a MOS transistor and a diode in combination, since Fig. 12A The solid line in FIG. 4 shows that the leakage current is low, so the power consumption increase can be easily reduced.

[0102] Fig. 12B is a schematic diagram showing a situation where a photon is detected after a period of time has passed since recharging. In response to the clock signal PCLKB becoming a low level at time t1, the PMOS transistor used as the quenching element 202 enters the on state, the cathode voltage VC rises due to the recharging, and the cathode voltage VC becomes the voltage value of the potential V2 (for example, 1.1V). After the charging is completed at time t2, since the leakage current is high in the case of a single PMOS transistor, the current flows from the third power supply 603 to the cathode of APD201. In the case where the cathode voltage VC after charging is a positive value (for example, 1.1V), the cathode voltage VC decreases in the negative direction. Therefore, the voltage Vex in the voltage corresponding to Vbd+Vex applied to APD 201 is reduced, and the avalanche multiplication rate is reduced, which produces a problem of reduced sensitivity of APD 201. On the other hand, by using a MOS transistor and a diode in combination, since Fig. 12B As shown by the solid line in , the leakage current is low, so the voltage drop of the cathode voltage VC can be easily suppressed.

[0103] Fig.13 : is a schematic plan view showing the configuration of a voltage control unit 604 and a quenching element 202 serving as a charging unit according to a third example. Fig.14 is along Fig.13 Schematic cross-sectional view taken along line XX' in FIG. Fig.13 and Fig.14The charging unit and the voltage control unit 604 according to this example are described, but the arrangement of the components is not limited thereto.

[0104] Fig.13 The quenching elements 202 and voltage control units 604 for four pixels are shown.

[0105] The quenching elements 202 of the four pixels are arranged near adjacent pixels. For example, the quenching elements 202 of the four pixels and a portion of the voltage control unit 604 share a well region 1107. The well region 1107 is an N-type well region. In this example, the PMOS transistor of the quenching element 202 and the PMOS transistor 1105 of the voltage control unit 604 are arranged in the N-type well region 1107. The PMOS transistor 2101 of the waveform shaping unit 210 is arranged in the well region 1107. Fig.14 As shown, the well region 1107 is configured in the P-type well region 1108 .

[0106] The NMOS transistor 2102 of the waveform shaping unit 210 is arranged in the well region 1108. The waveform shaping unit 210 includes a PMOS transistor 2101 and an NMOS transistor 2102. In a plan view, the well region 1107 is arranged between the P-type well regions 1108.

[0107] The diode 1106 of the voltage control unit 604 is configured in the P-type well region 1108. In this example, the diode 1106 includes an N-type active region 1109 and a P-type active region 1122. Here, in this example, the well contact region is configured between the NMOS transistor 2102 and the diode 1106. Specifically, the N-type well contact region 1111 and the P-type well contact region 1119 are configured around the diode 1106. This configuration prevents a parasitic bipolar from operating between the NMOS transistor 2102 and the diode 1106. This configuration can form a bipolar transistor in which the N-type well contact region 1111 is used as a collector, the P-type active region 1122 is used as a base, and the N-type active region 1109 is used as an emitter. In addition, with the N-type well contact region 1111, the operation of nearby transistors is less susceptible.

[0108] like Fig.14 As shown, the gate of each MOS transistor includes a gate electrode 1121 and a gate oxide film 1104. The element isolation region 1118 is configured between the PMOS transistor 1105 and the PMOS transistor 2101. The element isolation region 1118 may include, for example, a shallow trench isolation (STI) or a deep trench isolation (DTI) including an insulating member. The element isolation region 1118 may be a semiconductor isolation, or may include a semiconductor isolation and an insulating member.

[0109] FIG. 15A to FIG. 15Care schematic plan views each showing a part of a wiring layer included in the second wiring structure. Fig.15A shows a first wiring layer arranged close to a second semiconductor layer, Fig. 15B A second wiring layer is shown disposed between the first wiring layer and the first wiring structure, and Fig. 15C A third wiring layer is shown disposed between the second wiring layer and the first wiring structure. Other wiring layers may be disposed between the first wiring layer and the second semiconductor layer.

[0110] In the first wiring layer, the wiring pattern 1113, the wiring pattern 1114, the wiring pattern 1115, and the wiring pattern 1116 are arranged in a plan view to correspond to the quenching element 202, the voltage control unit 604, and the waveform shaping unit 210. The wiring pattern 1113 is a cathode wiring, and is connected to the cathode of the APD 201. The wiring pattern 1114 also serves as a wiring for supplying power and supplying potential to the anode of the APD 201. The wiring pattern 1114 is connected to the MOS transistor of the quenching element 202. The wiring pattern 1115 is a wiring for supplying a GND potential, and is connected to the anode of the diode 1106.

[0111] The wiring pattern 1116 is a signal wiring, and a signal output from the counter passes through the wiring pattern 1116 .

[0112] The wiring pattern 1113 of the first wiring layer is connected to the wiring pattern 1113 of the second wiring layer. Fig. 15B As shown, it is desirable that the wiring patterns 1113 are arranged obliquely to each other in a plan view and are as far away from the wiring patterns 1114 and 1115 as possible.

[0113] This can reduce the coupling capacitance between the wiring pattern 1113 used as cathode wiring and the wiring patterns 1114 and 1115 used as power wiring. The amount of charge generated in the recharging of the cathode voltage VC is determined by the cathode capacitance (including the capacitance of the cathode wiring) and the excess bias voltage. The reduction in the amount of charge generated in the recharging of the cathode potential leads to a reduction in power consumption.

[0114] The wiring pattern 1113 of the second wiring layer is connected to Fig. 15C The wiring pattern 1113 of the third wiring layer is shown. The wiring pattern 1115 of the second wiring layer is connected to Fig. 15C A wiring pattern 1115 of a third wiring layer is shown.

[0115] (Fourth Example)

[0116] Reference Fig.16 A fourth example included in the above-mentioned first embodiment is described. Fig.16 The photoelectric conversion unit 102 and part of the signal processing unit 1403 are shown.

[0117] In this example, the voltage control unit 604 includes a bipolar transistor 1120 and a PMOS transistor 1105. The voltage of the first power source 601 and the voltage of the third power source 603 are equal to each other.

[0118] The collector of the bipolar transistor 1120 is connected to the third power supply 603. The emitter of the bipolar transistor 1120 is connected to the source of the PMOS transistor 1105. The GND voltage is supplied to the base of the bipolar transistor 1120. For example, the voltage supplied to the base of the bipolar transistor 1120 is 1.1V.

[0119] The drain of the PMOS transistor 1105 is connected to the cathode of the APD 201. The drain of the PMOS transistor 1105 is connected to the gate of the PMOS transistor 1105. Due to the photocurrent generated after the avalanche multiplication, the cathode voltage VC drops and the PMOS transistor 1105 enters the on state. Therefore, a forward bias voltage is applied to the diode 1106 by the voltage of the third power supply 603 and the voltage of the cathode of the APD 201, and a current flows from the third power supply 603 toward the cathode of the APD 201. By this current, the cathode voltage VC increases, which prevents the cathode voltage VC from dropping to a value exceeding a predetermined value and prevents the withstand voltage of the MOS transistor included in the quenching element 202 from being exceeded. With this configuration, a photoelectric conversion device with high stability can be provided.

[0120] The drop in cathode voltage VC can be further suppressed by amplifying the current using the bipolar transistor 1120. The bipolar transistor 1120 can be a parasitic bipolar.

[0121] (Fifth Example)

[0122] Reference Fig.17 A fifth example included in the above-mentioned first embodiment is described. Fig.17 The photoelectric conversion unit 102 and part of the signal processing unit 1403 are shown.

[0123] In this example, the voltage control unit 604 includes a plurality of diodes. For example, the voltage control unit 604 may include three diodes. The amplitude conversion unit 610 is connected between the quenching element 202 and the cathode of the APD 201. For example, the amplitude conversion unit 610 may include a PMOS transistor. The amplitude conversion unit 610 controls the voltage at the node NodeA according to the gate voltage of the amplitude conversion unit 610. Because the amplitude of the cathode voltage VC (for example, 2.1V) is applied between the source and the drain of the MOS transistor, the amplitude conversion unit 610 is expected to use a transistor with a high withstand voltage. For example, a transistor with a withstand voltage of 2.5V is used. On the other hand, because the withstand voltage of the quenching element 202 and the waveform shaping unit 210 does not need to be so high, it is expected to use a transistor with a low withstand voltage. For example, the quenching element 202 and the waveform shaping unit 210 use a transistor with a withstand voltage of 1.3V.

[0124] The cathode of the APD 201 and the cathode of the diode are connected. Then, three diodes are connected in succession. According to this example as well, the cathode voltage VC is prevented from falling to a value exceeding a predetermined value, and is prevented from exceeding the withstand voltage of the MOS transistor included in the quenching element 202. With this configuration, a photoelectric conversion device with high stability can be provided. By connecting three diodes as in this example, control of the voltage of the cathode voltage VC is easier than in the case where control is performed by one diode.

[0125] Reference Fig.18 The operation in the case where the amplitude conversion unit 610 is provided will be described. Fig.18 is a diagram showing a clock signal, photon entry timing, cathode voltage VC, and a node NodeA between the quenching element 202 and the amplitude conversion unit 610. In response to the entry of photons and the decrease in cathode voltage VC, the voltage at the node NodeA also decreases. In this process, the amplitude conversion unit 610 can convert the amplitude Vex of the cathode voltage VC into the amplitude (VH) of the node NodeA. With this configuration, a low voltage transistor can be used as the quenching element 202 and the waveform shaping unit 210, and the layout area can be made smaller.

[0126] Fig.19 is a schematic plan view showing the configuration of the amplitude conversion unit 610 and the voltage control unit 604 according to this example, and Fig. 20 is along Fig.19 Schematic cross-sectional view taken along line XX' in FIG. In this example, the N-type well region 1107 and the P-type well region 1108 are arranged in the P-type substrate region 1117. The PMOS transistor 2103 included in the amplitude conversion unit 610 is arranged in the N-type well region 1107. The PMOS transistor 2103 is arranged between two diodes 1106 and one diode 1106.

[0127] Of the three diodes 1106, the center diode 1106 is connected to Fig.17 The diode 1106 is connected to the VC (cathode terminal of the APD 201) in the center. Therefore, it is desirable that the center diode 1106 is arranged adjacent to the PMOS transistor 2103. This reduces the cathode wiring capacitance and reduces power consumption. It is desirable that the diode 1106 arranged on the opposite side of the center diode 1106 relative to the PMOS transistor 2103 is a diode connected to the third power supply 603. Because the P-type substrate area can be shared with nearby transistors, the layout area is reduced.

[0128] (Sixth Example)

[0129] Reference Fig.21 A sixth example included in the above-mentioned first embodiment is described.

[0130] In this example, a portion of the voltage control unit 604 is shared by a plurality of APDs 201. The layout area is reduced.

[0131] like Fig.21 As shown, the voltage control unit 604 according to this example includes four diodes. Two diodes connected to the respective cathode voltages VC of the APD 201 in the voltage control unit 604 play a role in correctly detecting the signal from the APD 201. Therefore, the diode closest to the cathode voltage VC is configured for each APD 201, and the subsequent diodes are shared by a plurality of APDs 201.

[0132] exist Fig.21 Although a portion of the voltage control unit 604 is shared by two APDs 201 , the voltage control unit 604 may be shared by three or more APDs 201 .

[0133] (Seventh Example)

[0134] The seventh example is a modified example of the first to sixth examples, and will refer to Fig. 22 Describe this example. In this example, the anode (first terminal) of the APD 201 is connected to the first power source 1301 via the quenching element 202 used as a charging unit. The cathode (second terminal) of the APD 201 is connected to the second power source 1302. The NMOS transistor 1304 used as the voltage control unit 604 is connected to the anode of the APD 201. Specifically, the source of the NMOS transistor 1304 is connected to the anode of the APD 201, and the drain of the NMOS transistor 1304 is connected to the third power source 1303. Fig. 22, the voltage of the first power supply 1301 is represented by GND, the voltage of the second power supply 1302 is represented by VH, and the voltage of the third power supply 1303 is represented by VL. The voltage of the third power supply 1303 is a voltage value between the voltage of the first power supply 1301 and the voltage of the second power supply 1302. Specifically, the voltage of the first power supply 1301 is, for example, 0V, the voltage of the second power supply 1302 is, for example, 30V, and the voltage of the third power supply 1303 is, for example, 1.1V. The voltage of the third power supply 1303 may be equal to the voltage of the first power supply 1301. Specifically, the voltage of the first power supply 1301 is, for example, 0V, the voltage of the second power supply 1302 is, for example, 30V, and the voltage of the third power supply 1303 is, for example, 0V.

[0135] When the anode voltage VA increases due to the photocurrent generated after avalanche multiplication, and the anode voltage VA increases to the threshold value at which the NMOS transistor 1304 enters the on state, a current flows from the anode of the APD 201 to the third power supply 1303. By this current, the anode voltage decreases, which prevents the anode voltage VA from increasing to a value exceeding a predetermined value and preventing the withstand voltage of the MOS transistor from being exceeded. Thus, with this configuration, a photoelectric conversion device with high stability can be provided. Since the voltage control unit 604 can be implemented by configuring a single NMOS transistor, the area can be reduced.

[0136] In the first to sixth examples, the anode terminal and the cathode terminal may be interchanged as in this example.

[0137] (Eighth Example)

[0138] The eighth example is a variation of the first to seventh examples. In each of the above examples, by using a MOS transistor used as a charging unit, the presence or absence of electrical connection between the cathode of the APD 201 and the first power supply is switched according to a clock signal. The configuration is not limited to this, and the charging unit may be a resistor. A MOS transistor to which a clock signal is not input may be used as a charging unit. Specifically, passive charging may be performed.

[0139] For example, when the APD current under high illumination is higher than the recharge current generated by the charging unit, the cathode potential may exceed the withstand voltage of the MOS transistor. Even in this case, the voltage control unit 604 is used under high illumination, thereby ensuring the withstand voltage of the MOS transistor.

[0140] In the above embodiments, reference Figures 1 to 22 A photoelectric conversion device comprising two stacked layers is described.

[0141] Specifically, the above embodiment is an example in which the photoelectric conversion unit 102 is arranged on the sensor substrate 11 serving as the first substrate, the signal processing unit 103 is arranged on the circuit substrate 21 serving as the second substrate, and the first substrate and the second substrate are stacked on each other. Fig.23 A photoelectric conversion device in which a third substrate is stacked in addition to the first substrate and the second substrate is described. Fig.23 The photoelectric conversion unit 102 , a part of the signal processing unit 1403 , and another part of the signal processing unit 1404 are shown.

[0142] exist Fig.23 In the embodiment, the photoelectric conversion unit 102 is arranged on a sensor substrate serving as a first substrate.

[0143] The first signal processing unit including the quenching element 202, the voltage control unit 604, and the waveform shaping unit 210 is arranged on the first circuit substrate used as the second substrate. In addition, the second signal processing unit including the counter circuit and the selection circuit is arranged on the second circuit substrate used as the third substrate. Then, the first substrate, the second substrate, and the third substrate are stacked on each other.

[0144] The APD 201 has a large voltage change due to avalanche multiplication at the cathode or anode. For this reason, as the MOS transistor included in the quenching element 202 used as a charging unit, the element (e.g., MOS transistor) included in the voltage control unit 604, and the element (e.g., MOS transistor) included in the waveform shaping unit 210, a MOS transistor with a high withstand voltage is used. On the other hand, the output from the waveform shaping unit 210 is a digital signal with a pulse waveform, and a MOS transistor with a high withstand voltage may not be used. On the other hand, in the signal processing circuit of the latter stage of the waveform shaping unit 210, a lower voltage can be achieved by using a MOS transistor with a low withstand voltage, which enables lower power consumption. The use of a MOS transistor with a low withstand voltage enables miniaturization of transistors, which also enables space saving. For example, the thickness of the gate oxide film of a MOS transistor with a high withstand voltage is thicker than that of a MOS transistor with a low withstand voltage. The channel length of a MOS transistor with a high withstand voltage is longer than that of a MOS transistor with a low withstand voltage. Regarding the configuration of the first substrate and the second substrate, the configurations in the various examples described in the first embodiment can be adopted.

[0145] refer to Fig.24 , a photoelectric conversion system according to a third embodiment is described. Fig.24 is a block diagram showing a general configuration of a photoelectric conversion system according to the present embodiment.

[0146] The photoelectric conversion device described in each of the first embodiment and the second embodiment is applicable to various photoelectric conversion systems. Examples of various photoelectric conversion systems include digital still cameras, digital video cameras, surveillance cameras, copiers, fax machines, mobile phones, vehicle-mounted cameras, and observation satellites. Various photoelectric conversion systems also include a camera module including an optical system such as a lens and an imaging device. Fig.24 A block diagram of a digital still camera is shown as one of these examples.

[0147] Fig.24 The illustrated photoelectric conversion system includes an image pickup device 1004 as an example of a photoelectric conversion device, and a lens 1002 for forming an optical image of a subject on the image pickup device 1004. The photoelectric conversion system further includes an aperture 1003 for changing the amount of light passing through the lens 1002, and a baffle 1001 for protecting the lens 1002. The lens 1002 and the aperture 1003 function as an optical system for collecting light onto the image pickup device 1004. The image pickup device 1004 is a photoelectric conversion device according to any of the above-described embodiments, and converts the optical image formed by the lens 1002 into an electrical signal.

[0148] The photoelectric conversion system also includes a signal processing unit 1007 serving as an image generating unit for processing an output signal output from the image pickup device 1004 to generate an image. The signal processing unit 1007 performs an operation for performing various types of correction and compression as required and outputting image data. The signal processing unit 1007 may be formed on a semiconductor substrate configured with the image pickup device 1004, or may be formed on a semiconductor substrate different from the image pickup device 1004.

[0149] The photoelectric conversion system also 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. The photoelectric conversion system also includes a recording medium 1012 such as a semiconductor memory or the like for recording or reading therefrom captured data and a recording medium control interface unit (recording medium control I / F unit) 1011 for recording or reading image data in or from the recording medium 1012. The recording medium 1012 may be built in the photoelectric conversion system, or may be attached to and detached from the photoelectric conversion system.

[0150] Furthermore, the photoelectric conversion system according to the present embodiment includes an overall control / computation unit 1009 for performing various calculations and controlling the overall operation of the digital still camera, and a timing generation unit 1008 for outputting various timing signals to the image pickup device 1004 and the signal processing unit 1007. The timing signal may be input from the outside, and the photoelectric conversion system may need to include at least the image pickup device 1004 and the signal processing unit 1007 for processing the output signal output from the image pickup device 1004.

[0151] The imaging device 1004 outputs an imaging signal to the 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.

[0152] As described above, according to the present embodiment, a photoelectric conversion system to which the photoelectric conversion apparatus (imaging apparatus) according to any of the above-described embodiments is applied can be realized.

[0153] refer to Fig.25A and Fig.25B , a photoelectric conversion system and a moving body according to a fourth embodiment are described. Fig.25A and Fig.25B is a diagram showing the configuration of a photoelectric conversion system and a moving body according to the present embodiment.

[0154] Fig.25A An example of a photoelectric conversion system related to a vehicle-mounted camera is shown. The photoelectric conversion system 2300 includes a camera 2310. The camera 2310 is a photoelectric conversion device according to any of the above-described embodiments. The photoelectric conversion system 2300 includes an image processing unit 2312 for performing image processing on a plurality of image data acquired by the camera 2310, and a parallax acquisition unit 2314 for calculating parallax (phase difference between parallax images) based on a plurality of image data acquired by the photoelectric conversion system 2300. The photoelectric conversion system 2300 also includes a distance measurement unit 2316 for measuring the distance to a target object based on the calculated parallax, and a collision judgment unit 2318 for judging whether there is a possibility of a collision based on the calculated distance. The parallax acquisition unit 2314 and the distance measurement unit 2316 are examples of a distance information acquisition unit for acquiring distance information related to the distance to the target object. That is, the distance information is information related to the parallax, the defocus amount, and the distance to the target object. The collision determination unit 2318 may use any of these distance information to determine the possibility of a collision. The distance information acquisition unit may be implemented by specially designed hardware, or may be implemented by a software module.

[0155] Alternatively, the distance information acquisition unit may be implemented by a field programmable gate array (FPGA) or an application specific integrated circuit (ASIC), or may be implemented by a combination thereof.

[0156] The photoelectric conversion system 2300 is connected to the 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 electronic control unit (ECU) 2330, which is a control unit that generates braking force in 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, which issues an alarm to the driver based on the judgment result of the collision judgment unit 2318. For example, if there is a high possibility of collision as a judgment result of the collision judgment unit 2318, the control ECU 2330 brakes, releases the accelerator, or suppresses the engine output to control the vehicle to avoid collision and reduce damage. The alarm device 2340 warns the user by issuing an alarm that causes a sound, etc., displaying an alarm message on the screen of the car navigation system, or applying vibration to the seat belt or the steering wheel.

[0157] In this embodiment, the photoelectric conversion system 2300 captures the surrounding environment of the vehicle (such as the front direction or the rear direction). Fig.25B The photoelectric conversion system 2300 is shown in the case where the photoelectric conversion system 2300 captures the front direction of the vehicle (imaging range 2350). The vehicle information acquisition device 2320 sends an instruction to the photoelectric conversion system 2300 or the imaging device 2310. With this configuration, the accuracy of distance measurement can be further improved.

[0158] In the above description, an example of controlling a vehicle to avoid collision with other vehicles is described. Alternatively, the present embodiment is also applicable to control of autonomous driving to follow other vehicles or control of autonomous driving to avoid lane deviation. In addition, the photoelectric conversion system can be applied not only to vehicles such as automobiles, but also to mobile bodies (mobile devices) such as ships, airplanes, or industrial robots. In addition, in addition to mobile bodies, the photoelectric conversion system can also be applied to devices that widely use object recognition such as intelligent transportation systems (ITS).

[0159] refer to Fig.26 , a photoelectric conversion system according to a fifth embodiment is described. Fig.26 : is a block diagram showing an example of the configuration of a distance image sensor including the photoelectric conversion system according to the present embodiment.

[0160] like Fig.26As shown, the distance image sensor 401 includes an optical system 402, a photoelectric conversion device 403, an image processing circuit 404, a monitor 405, and a memory 406. Then, the distance image sensor 401 acquires a distance image corresponding to the distance to the subject by receiving light (modulated light or pulse light) that has been projected toward the subject from the light source device 411 and reflected from the surface of the subject.

[0161] The optical system 402 includes one or more lenses, and forms an image on a light receiving surface (sensor unit) of the photoelectric conversion device 403 by guiding image light (incident light) from a subject to the photoelectric conversion device 403 .

[0162] As the photoelectric conversion device 403 , the photoelectric conversion device according to each of the above-described embodiments is applied, and a distance signal indicating a distance obtained from a light reception signal output from the photoelectric conversion device 403 is supplied to the image processing circuit 404 .

[0163] The image processing circuit 404 performs image processing to construct a distance image based on the distance signal supplied from the photoelectric conversion device 403. Then, the distance image (image data) obtained by the image processing is supplied and displayed on the monitor 405, or supplied and stored (recorded) in the memory 406.

[0164] Applying the above-described photoelectric conversion device to the distance image sensor 401 having the above-described configuration enables, for example, acquisition of a more accurate distance image according to improved characteristics of pixels.

[0165] refer to Fig. 27 , a photoelectric conversion system according to a sixth embodiment is described. Fig. 27 : is a diagram showing an example of a general configuration of an endoscopic surgery system as a photoelectric conversion system according to the present embodiment.

[0166] Fig. 27 FIG. 1 shows a state in which a user (doctor) 1131 uses an endoscopic surgery system 1700 to perform surgery on a patient 1132 on a bed 1133. Fig. 27 As shown, the endoscopic surgery system 1700 includes an endoscope 1100, a surgical tool 1110, and a cart 1134 equipped with various devices used for endoscopic surgery.

[0167] The endoscope 1100 includes a barrel 1101 having a portion of a predetermined length inserted from the front end of the barrel 1101 into the body cavity of a patient 1132 and a camera head 1102 connected to the base end of the barrel 1101. Fig. 27 In the illustrated example, although the endoscope 1100 is configured as a so-called rigid scope including a rigid lens barrel 1101 , the endoscope 1100 may be configured as a so-called flexible scope including a flexible lens barrel.

[0168] An opening portion in which an objective lens is embedded is at the front end of the lens barrel 1101. A light source device 1203 is connected to the endoscope 1100. Light generated by the light source device 1203 is guided to the front end of the lens barrel 1101 through a light guide extending inside the lens barrel 1101, passes through the objective lens, and is emitted toward an observation object in a body cavity of a patient 1132. The endoscope 1100 may be a direct-view endoscope, or may be an oblique-view endoscope, or may be a side-view endoscope.

[0169] The optical system and the photoelectric conversion device are configured in the camera head 1102, and the optical system collects the reflected light (observation light) from the observation object on the photoelectric conversion device. The photoelectric conversion device performs photoelectric conversion on the observation light and generates an electrical signal corresponding to the observation light (i.e., an image signal corresponding to the observation image). The photoelectric conversion device according to each of the above-mentioned embodiments can be used as a photoelectric conversion device. The image signal is transmitted to the camera control unit (CCU) 1135 as RAW data.

[0170] The CCU 1135 includes a central processing unit (CPU) and a graphics processing unit (GPU), and integrally controls the operations of the endoscope 1100 and the display device 1136. In addition, the CCU 1135 receives an image signal from the camera 1102, and performs various types of image processing such as development processing (demosaic processing) on ​​the image signal for displaying an image based on the image signal.

[0171] Based on the control of the CCU 1135 , the display device 1136 displays an image based on the image signal subjected to the image processing performed by the CCU 1135 .

[0172] The light source device 1203 includes a light source such as a light emitting diode (LED) and supplies the endoscope 1100 with emission light for imaging of a surgical site.

[0173] The input device 1137 is an input interface for inputting to the endoscopic surgery system 1700. The user can input various information and input instructions to the endoscopic surgery system 1700 via the input device 1137.

[0174] The treatment tool control device 1138 controls the driving of the energy treatment tool 1112 for burning or cutting tissue or sealing a blood vessel.

[0175] The light source device 1203 that supplies the emitted light for photographing the surgical site to the endoscope 1100 may include, for example, an LED, a laser light source, or a white light source configured by a combination of these light sources. In the case of a white light source including 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 photographed image can be adjusted in the light source device 1203. In this case, laser light is emitted from each RGB laser light source to the observed object in a time-division manner, and the driving of the imaging element of the camera 1102 is controlled synchronously with the emission timing of the laser light, thereby also photographing images corresponding to each RGB in a time-division manner. According to this method, a color image can be obtained without providing a color filter in the imaging element.

[0176] The driving of the light source device 1203 can be controlled in such a manner that the intensity of light to be output from the light source device 1203 changes every predetermined time. Images are acquired in a time-division manner by controlling the driving of the imaging element of the camera 1102 in synchronization with the timing of the change in light intensity, and the images are synthesized, thereby generating a high dynamic range image without so-called dark part loss and highlight blown out.

[0177] The light source device 1203 may also be configured to supply light of a predetermined wavelength band suitable for special light observation. In special light observation, for example, the wavelength dependence of light absorption in body tissue is utilized. Specifically, light of a narrower band than that emitted in normal observation (i.e., white light) is emitted, thereby capturing an image of a predetermined tissue such as blood vessels in a mucosal surface layer with high contrast.

[0178] Alternatively, in special light observation, fluorescence observation for obtaining an image using fluorescence generated by emitting excitation light may be performed. In fluorescence observation, fluorescence from body tissue is observed by emitting excitation light onto body tissue, or a fluorescent image is obtained by locally injecting an agent such as indocyanine green (ICG) into body tissue and emitting excitation light of a fluorescence wavelength suitable for the agent onto the body tissue. The light source device 1203 may be configured to supply narrowband light and / or excitation light suitable for such special light observation.

[0179] refer to Fig.28A and Fig.28B , a photoelectric conversion system according to a seventh embodiment is described. Fig.28AGlasses 1600 (smart glasses) are shown as a photoelectric conversion system according to the present embodiment. Glasses 1600 include a photoelectric conversion device 1602. The photoelectric conversion device 1602 is the photoelectric conversion device described in any of the above-mentioned embodiments. On the back side of the lens 1601, a display device including a light-emitting device such as an organic light-emitting diode (OLED) or an LED may be configured. The number of photoelectric conversion devices 1602 may be one or more than one. In addition, a plurality of types of photoelectric conversion devices 1602 may be used in combination. The arrangement position of the photoelectric conversion device 1602 is not limited to Fig.28A Position shown.

[0180] The glasses 1600 further include a control device 1603. The control device 1603 serves as a power source for supplying power to the photoelectric conversion device 1602 and the above-mentioned display device. The control device 1603 also controls the operation of the photoelectric conversion device 1602 and the display device. In the lens 1601, an optical system for focusing light to the photoelectric conversion device 1602 is formed.

[0181] Fig.28B Glasses 1610 (smart glasses) are shown as an application example. Glasses 1610 include a control device 1612, and the control device 1612 is equipped with a photoelectric conversion device equivalent to the photoelectric conversion device 1602, and a display device. In the lens 1611, an optical system for projecting light emitted from the photoelectric conversion device and the display device in the control device 1612 is formed, and an image is projected onto the lens 1611. The control device 1612 serves as a power supply for supplying 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 1612 may include a line of sight detection unit for detecting the line of sight of the wearer (user). Infrared light can be used for the detection of the line of sight. The infrared light emitting unit emits infrared light to the eyeball of the user who views the displayed image. The camera unit including the light receiving element detects the reflected light of the emitted infrared light that has been reflected from the eyeball, thereby obtaining a captured image of the eyeball. A reduction unit for reducing the light from the infrared light emitting unit to the display unit in the plan view is configured so that the degradation of the image quality is suppressed.

[0182] The user's line of sight relative to the displayed image is detected using a captured image of the eyeball obtained by imaging using infrared light. Any known method can be applied to line of sight detection using a captured image of the eyeball. As an example, a line of sight detection method based on a Purkinje image obtained by reflection of irradiated light on the cornea can be used.

[0183] More specifically, a line of sight detection process based on the pupil center corneal reflection method is performed. Based on the image of the pupil and the Purkinje image included in the captured image of the eyeball, the pupil center corneal reflection method is used to calculate the line of sight vector representing the direction (rotation angle) of the eyeball, thereby detecting the user's line of sight.

[0184] The display device of the present embodiment may include a photoelectric conversion device including a light receiving element, and may control a display image on the display device based on line of sight information about the user from the photoelectric conversion device.

[0185] Specifically, in the display device, a first field of view area viewed by the user and a second field of view area other than the first field of view area are determined 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 the display device may receive the first field of view area and the second field of view area determined by 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. More specifically, the resolution of the second field of view area may be set to be lower than the resolution of the first field of view area.

[0186] In addition, the display area includes a first display area and a second display area different from the first display area. Based on the line of sight information, an area with a high priority can be determined from the first display area and the second display area. The first display area and the second display area can be determined by the control device of the display device, or the display device can receive the first display area and the second display area determined by an external control device. Control can be performed in a manner such that the resolution of the area with a high priority is controlled to be higher than the resolution of the area other than the area with a high priority. In other words, the resolution of the area with a relatively low priority can be set to a low resolution.

[0187] Artificial intelligence (AI) can be used to determine the first field of view area and the area with high priority. AI can be a model configured to estimate the angle of sight and the distance to the target object at the end of the sight from the image of the eyeball by using training data including the image of the eyeball and the direction in which the eyeball is actually looking in the image. The AI ​​program can be included in the display device, the photoelectric conversion device, or the external device. In the case where the external device includes the AI ​​program, the AI ​​program is transmitted to the display device via communication.

[0188] In the case of display control based on line of sight detection, the present invention can be appropriately applied to smart glasses that also include a photoelectric conversion device for capturing external images. The smart glasses can display external information obtained by capturing images in real time.

[0189] The above-described photoelectric conversion apparatus and photoelectric conversion system can be applied to electronic devices such as so-called smartphones and tablets, for example.

[0190] Fig.29A and Fig.29B is a diagram showing an example of an electronic device 1500 in which a photoelectric conversion apparatus is mounted. Fig.29A The front of the electronic device 1500 is shown, and Fig.29B The back side of the electronic device 1500 is shown.

[0191] like Fig.29A As shown, a display 1510 for displaying an image is arranged at the center of the front of the electronic device 1500. Along the upper side of the front of the electronic device 1500, front cameras 1521 and 1522 each using a photoelectric conversion device, an infrared (IR) light source 1530 for emitting infrared light, and a visible light source 1540 for emitting visible light are arranged.

[0192] like Fig.29B As shown, along the upper side of the back side of the electronic device 1500, rear cameras 1551 and 1552, each using a photoelectric conversion device, an IR light source 1560 for emitting infrared light, and a visible light source 1570 for emitting visible light are arranged.

[0193] In the electronic device 1500 having such a configuration, by applying the above-mentioned photoelectric conversion device, for example, it is possible to capture a higher quality image. In addition, the photoelectric conversion device can be applied to electronic devices such as infrared sensors, distance measurement sensors using active infrared light sources, security cameras, or personal or biometric authentication cameras. This application increases the accuracy and performance of these electronic devices.

[0194] Fig.30 3 is a block diagram of an X-ray computed tomography (CT) apparatus according to a ninth embodiment. This embodiment can be applied to both the first embodiment and the second embodiment. The X-ray CT apparatus 30 according to this embodiment includes an X-ray generating unit 310, a wedge 311, a collimator 312, an X-ray detecting unit 320, a top plate 330, a rotating frame 340, and a high voltage generating device 350. The X-ray CT apparatus 30 includes a data collecting device (data acquisition system: DAS) 351, a signal processing unit 352, a display unit 353, and a control unit 354.

[0195] For example, the X-ray generating unit 310 includes a vacuum tube for generating X-rays. High voltage and filament current from the high voltage generating device 350 are supplied to the vacuum tube of the X-ray generating unit 310. X-rays are generated by emitting thermal electrons from the cathode (filament) toward the anode (target).

[0196] The wedge 311 is a filter for adjusting the amount of X-rays emitted from the X-ray generation unit 310. The wedge 311 attenuates the amount of X-rays in such a manner that the X-rays emitted from the X-ray generation unit 310 to the subject have a predetermined distribution. The collimator 312 includes a lead plate that narrows the emission range of the X-rays that have passed through the wedge 311. The X-rays generated by the X-ray generation unit 310 are formed into a cone beam shape via the collimator 312 and emitted to the subject on the top plate 330.

[0197] The X-ray detection unit 320 includes the semiconductor device in the first and second embodiments. The X-ray detection unit 320 detects X-rays that have been generated by the X-ray generation unit 310 and passed through the subject, and outputs a signal corresponding to the X-ray amount together with the DAS 351 .

[0198] The rotating frame 340 has an annular shape and is configured to be rotatable. In the rotating frame 340, the X-ray generation unit 310 (wedge 311, collimator 312) and the X-ray detection unit 320 are configured to face each other. The X-ray generation unit 310 and the X-ray detection unit 320 can rotate together with the rotating frame 340.

[0199] The high voltage generating device 350 includes a boosting circuit, and outputs a high voltage to the X-ray generating unit 310. The DAS 351 includes an amplifying circuit and an analog-to-digital (A / D) conversion circuit, and outputs a signal from the X-ray detecting unit 320 to the signal processing unit 352 as digital data.

[0200] The signal processing unit 352 includes a central processing unit (CPU), a read-only memory (ROM), and a random access memory (RAM), and performs image processing on digital data. The display unit 353 includes a flat display device and displays an X-ray image. The control unit 354 includes a CPU, a ROM, and a RAM, and controls the overall operation of the X-ray CT apparatus 30.

[0201] The tenth embodiment can be applied to both the first embodiment and the second embodiment. Fig.31A is a schematic diagram showing an apparatus 9191 including the semiconductor device 930 according to the present embodiment.

[0202] As the semiconductor device 930, the photoelectric conversion device (imaging device) according to each of the above-described embodiments can be used. The device 9191 including the semiconductor device 930 will be described in detail. The semiconductor device 930 includes a semiconductor device 910. In addition to the semiconductor device 910, the semiconductor device 930 may include a package 920 that stores the semiconductor device 910. The package 920 includes a base member to which the semiconductor device 910 is fixed and a cover member such as glass facing the semiconductor device 910. The package 920 may also include a bonding member such as a bonding wire or a bump that connects a terminal configured in the base member and a terminal configured in the semiconductor device 910.

[0203] The device 9191 includes at least any one of an optical device 940, a control device 950, a processing device 960, a display device 970, a storage device 980, and a mechanical device 990. The optical device 940 supports the semiconductor device 930. The optical device 940 is, for example, a lens, a shutter, or a reflector, and includes an optical system for guiding light to the semiconductor device 930. The control device 950 controls the semiconductor device 930. The control device 950 is, for example, a semiconductor device such as an ASIC.

[0204] The processing device 960 processes a signal output from the semiconductor device 930. The processing device 960 is a semiconductor device such as a CPU or an ASIC for forming an analog front end (AFE) or a digital front end (DFE). The display device 970 is an electroluminescent (EL) display device or a liquid crystal display device for displaying information (image) obtained in the semiconductor device 930. The storage device 980 is a magnetic device or a semiconductor device for storing information (image) obtained in the semiconductor device 930. The storage device 980 is a volatile memory such as a static RAM (SRAM) or a dynamic RAM (DRAM) or a non-volatile memory such as a flash memory or a hard disk drive.

[0205] The mechanical device 990 includes a moving unit or a propulsion unit such as a motor or an engine. In the device 9191, a signal output from the semiconductor device 930 is displayed on the display device 970 and transmitted to the outside through a communication device (not shown) included in the device 9191. In this configuration, in addition to the storage circuit and the computing circuit included in the semiconductor device 930, it is desirable that the device 9191 further includes a storage device 980 and a processing device 960. The mechanical device 990 can be controlled based on the signal output from the semiconductor device 930.

[0206] The device 9191 is suitable for an electronic device such as an information terminal (e.g., a smart phone or a wearable terminal) or a camera (e.g., an interchangeable lens camera, a compact camera, a video camera, a surveillance camera) having a camera function. The mechanical device 990 in the camera drives a component of the optical device 940 for zooming, focusing, or shutter operation. Alternatively, the mechanical device 990 in the camera moves the semiconductor device 930 to perform an image stabilization operation.

[0207] The device 9191 may be a transport device such as a vehicle, a ship, or an aircraft (drone, airplane, etc.). The mechanical device 990 in the transport device may be used as a mobile device. The device 9191 used as a transport device is suitable for a device for transporting a semiconductor device 930 or a device for assisting driving (steering) and / or automating driving (steering) using a camera function. The processing device 960 for assisting driving (steering) and / or automating driving (steering) performs processing for operating the mechanical device 990 used as a mobile device based on information obtained in the semiconductor device 930. Alternatively, the device 9191 may be a medical device such as an endoscope, a measuring device such as a distance measuring sensor, an analytical device such as an electron microscope, an office device such as a copier, or an industrial device such as a robot.

[0208] According to the above-described embodiments, desired pixel characteristics can be obtained. This leads to an enhancement in the value of the semiconductor device. The enhancement in value corresponds to at least one of the addition of functions, performance improvement, characteristic improvement, reliability improvement, manufacturing yield improvement, environmental burden reduction, cost reduction, miniaturization, and light weight.

[0209] Therefore, the use of the semiconductor device 930 according to the present embodiment in the device 9191 also enhances the value of the device 9191. For example, the transport device equipped with the semiconductor device 930 achieves excellent performance in capturing images of the outside of the transport device or measuring the external environment. Therefore, it is determined that the semiconductor device according to the present embodiment will be installed on the transport device when manufacturing and selling the transport device, which is conducive to improving the performance of the transport device itself. The semiconductor device 930 is particularly suitable for a transport device that uses the information obtained in the semiconductor device 930 to perform driving assistance and / or automatic operation of the transport device.

[0210] Reference Fig.31B A photoelectric conversion system and a moving body according to the present embodiment are described.

[0211] Fig.31BAn example of a photoelectric conversion system related to a vehicle-mounted camera is shown. The photoelectric conversion system 8 includes a photoelectric conversion device 80. The photoelectric conversion device 80 is a photoelectric conversion device (imaging device) according to any of the above-described embodiments. The photoelectric conversion system 8 includes an image processing unit 801 for performing image processing on a plurality of image data acquired by the photoelectric conversion device 80 and a parallax acquisition unit 802 for calculating parallax (phase difference between parallax images) from a plurality of image data acquired by the photoelectric conversion system 8. Here, the photoelectric conversion system 8 may include an optical system (not shown) such as a lens, a shutter, or a reflective mirror that guides light to the photoelectric conversion device 80.

[0212] A plurality of photoelectric conversion units approximately equivalent to the pupil of the optical system may be configured in the pixels included in the photoelectric conversion device 80. For example, a plurality of photoelectric conversion units approximately equivalent to the pupil are configured in a manner corresponding to one microlens. The photoelectric conversion device 80 outputs image data corresponding to the light beams having passed through different positions of the pupil of the optical system by receiving light beams through the plurality of photoelectric conversion units. Then, the parallax acquisition unit 802 may calculate the parallax using the output image data. The photoelectric conversion system 8 further includes a distance acquisition unit 803 for calculating the distance from the target object based on the calculated parallax and a collision judgment unit 804 for judging whether a collision may occur based on the calculated distance. In the present embodiment, the parallax acquisition unit 802 and the distance acquisition unit 803 are used as an example of a distance information acquisition unit for acquiring distance information related to the distance from the target object. More specifically, the distance information is information related to the parallax, the defocus amount, and the distance from the target object. The collision judgment unit 804 may judge the possibility of collision using any of these distance information. The distance information may be acquired using the time of flight (ToF) technology. The distance information acquisition unit can be implemented by specially designed hardware, or can be implemented by a software module. The distance information acquisition unit can be implemented by FPGA or ASIC, or can be implemented by a combination of these.

[0213] The photoelectric conversion system 8 is connected to the vehicle information acquisition device 810, and can acquire vehicle information such as vehicle speed, yaw rate, and steering angle. An electronic control unit (ECU) 820 is connected to the photoelectric conversion system 8. The ECU 820 is used as a control device that outputs a control signal for causing the vehicle to generate a braking force based on the judgment result obtained by the collision judgment unit 804. The photoelectric conversion system 8 is also connected to an alarm device 830, which issues an alarm to the driver based on the judgment result obtained by the collision judgment unit 804. For example, in the case where the judgment result obtained by the collision judgment unit 804 indicates that the possibility of collision is high, the control ECU 820 performs vehicle control for avoiding collision or reducing damage by braking, releasing the accelerator, or suppressing the engine output. The alarm device 830 issues an alarm to the user by issuing an alarm such as a sound, displaying a warning message on the screen of the car navigation system, or vibrating the seat belt or the steering wheel.

[0214] In the present embodiment, the photoelectric conversion system 8 captures, for example, an image of the surroundings of the vehicle (such as a front image or a rear image).

[0215] Fig.31C A photoelectric conversion system for capturing a front image of a vehicle (imaging range 850) is shown. The vehicle information acquisition device 810 issues an instruction to the photoelectric conversion system 8 or the photoelectric conversion device 80. With this configuration, the accuracy of distance measurement can be further enhanced.

[0216] The above describes an example of performing control to avoid collision with other vehicles. The photoelectric conversion system may also be applicable to control for autonomous driving to follow other vehicles or control for autonomous driving to avoid lane deviation. In addition, the photoelectric conversion system 8 is applicable not only to vehicles such as cars, but also to mobile bodies (mobile devices) such as ships, airplanes, or industrial robots. The mobile body includes a driving force generating unit for generating a driving force mainly used for the movement of the mobile body and one or both of a rotating body mainly used for the movement of the mobile body. The driving force generating unit may be an engine or a motor, etc. The rotating body may be a tire, a wheel, a propeller of a ship, or a propeller of an aircraft, etc. In addition, in addition to mobile bodies, the photoelectric conversion system may also be applied to devices that widely use object recognition, such as intelligent transportation systems (ITS), etc.

[0217] Various devices are described in the above examples, but mechanical devices may also be included. The mechanical device in the camera may drive components of the optical device for zooming, focusing or shutter operation. Alternatively, the mechanical device in the camera may move the photoelectric conversion device for image stabilization operation.

[0218] The device may be a transport device such as a vehicle, a ship or an aircraft. The mechanical device in the transport device may be used as a mobile device. The device used as a transport device is suitable for a device for transporting a photoelectric conversion device or a device that uses a camera function to assist driving (steering) and / or automate driving (steering). The processing device for assisting driving (steering) and / or automating driving (steering) performs processing for operating the mechanical device used as a mobile device based on information obtained in the photoelectric conversion device.

[0219] [Varied Embodiment]

[0220] The present invention is not limited to the above-described embodiments, and various modifications may be made without departing from the scope of the present invention. For example, examples in which a partial configuration of an embodiment is added to an example of another embodiment and an example in which a partial configuration of an embodiment is replaced with a partial configuration of another embodiment are also included in embodiments of the present invention. The above-described embodiments may be implemented individually, or may be implemented as a combination of its multiple elements or features when necessary, or may be implemented in a single embodiment when a combination of elements or features from various embodiments is beneficial.

[0221] In the above-mentioned embodiment(s), an example in which a MOS transistor is applied as a transistor is described, but a transistor other than a MOS transistor may be applied. For example, a bipolar transistor may be used instead of a MOS transistor.

[0222] The photoelectric conversion systems described in the third and fourth embodiments above 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 Fig.24 , Fig.25A and Fig.25B The same applies to the ToF system described in the fifth embodiment, the endoscope described in the sixth embodiment, the smart glasses described in the seventh embodiment, the smart phone described in the eighth embodiment, the CT device described in the ninth embodiment, and the apparatus described in the tenth embodiment.

[0223] The above embodiments are merely examples of embodiments for carrying out the present invention, and the technical scope of the present invention should not be construed as being limited by these embodiments. That is, the present invention can be implemented in various forms without departing from its technical concept or main features.

[0224] As used herein, the phrase "A or B" and the phrase "at least one of A and B" may include all possible combinations of the listed items, unless otherwise explicitly defined. In addition, expressions such as "at least one of A or / and B" and "one or more than one of A or / and B" may include all possible combinations of the listed items, unless otherwise explicitly defined. That is, the above expressions are understood to disclose all of the following situations: in the case of including at least one A, in the case of including at least one B, and in the case of including both at least one A and at least one B. The same applies to combinations of three or more elements.

[0225] The present disclosure includes the following configurations and methods.

[0226] (Configuration 1)

[0227] A photoelectric conversion device, comprising:

[0228] an avalanche photodiode having a first terminal and a second terminal;

[0229] a first power source connected to the first terminal;

[0230] a second power source connected to the second terminal;

[0231] a charging unit configured to control a voltage of the first terminal;

[0232] a voltage control unit connected to the first terminal and configured to control a voltage of the first terminal according to a voltage of the first terminal; and

[0233] A third power supply is connected to the voltage control unit.

[0234] (Configuration 2)

[0235] The photoelectric conversion device according to Configuration 1, wherein a voltage of the third power supply is a voltage between a voltage of the first power supply and a voltage of the second power supply.

[0236] (Configuration 3)

[0237] The photoelectric conversion device according to Configuration 1, wherein a voltage of the third power supply is equal to a voltage of the first power supply.

[0238] (Configuration 4)

[0239] According to the photoelectric conversion device of configuration 1,

[0240] The voltage control unit includes a metal oxide semiconductor transistor, namely a MOS transistor.

[0241] wherein one terminal of the MOS transistor is connected to the first terminal, and

[0242] The other terminal of the MOS transistor is connected to the third power source.

[0243] (Configuration 5)

[0244] The photoelectric conversion device according to Configuration 1 or 4, wherein a gate of the MOS transistor is connected to the first terminal.

[0245] (Configuration 6)

[0246] The photoelectric conversion device according to any one of Configurations 1 to 5, wherein the MOS transistor is a P-type MOS transistor.

[0247] (Configuration 7)

[0248] The photoelectric conversion device according to any one of Configurations 1 to 5, wherein the MOS transistor is an N-type MOS transistor.

[0249] (Configuration 8)

[0250] According to the photoelectric conversion device of configuration 1,

[0251] Wherein, the voltage control unit includes a diode,

[0252] wherein one terminal of the diode is connected to the first terminal, and

[0253] The other terminal of the diode is connected to the third power source.

[0254] (Configuration 9)

[0255] The photoelectric conversion device according to any one of Configurations 1 to 8,

[0256] wherein the one terminal of the diode is a cathode, and

[0257] Wherein, the other terminal of the diode is an anode.

[0258] (Configuration 10)

[0259] The photoelectric conversion device according to any one of Configurations 1 to 8,

[0260] Wherein, the voltage control unit further comprises a metal oxide semiconductor transistor, namely a MOS transistor,

[0261] wherein one terminal of the MOS transistor is connected to the first terminal, and

[0262] The other terminal of the MOS transistor is connected to the third power source via the diode.

[0263] (Configuration 11)

[0264] The photoelectric conversion device according to any one of Configurations 1 to 10, wherein a gate of the MOS transistor is connected to the first terminal.

[0265] (Configuration 12)

[0266] The photoelectric conversion device according to any one of Configurations 1 to 11, wherein the MOS transistor is a P-type MOS transistor.

[0267] (Configuration 13)

[0268] The photoelectric conversion device according to any one of Configurations 1 to 11, wherein the MOS transistor is an N-type MOS transistor.

[0269] (Configuration 14)

[0270] The photoelectric conversion device according to Configuration 1, wherein the first terminal is a cathode of the avalanche photodiode.

[0271] (Configuration 15)

[0272] The photoelectric conversion device according to Configuration 1, wherein the first terminal is an anode of the avalanche photodiode.

[0273] (Configuration 16)

[0274] The photoelectric conversion device according to configuration 1, further comprising a waveform shaping unit connected to the first terminal,

[0275] Wherein, the waveform shaping unit is connected to the voltage control unit.

[0276] (Configuration 17)

[0277] The photoelectric conversion device according to any one of Configurations 1 to 16, further comprising:

[0278] a first substrate on which the avalanche photodiode is disposed;

[0279] a second substrate on which a first signal processing unit is disposed, the first signal processing unit comprising the charging unit, the voltage control unit and the waveform shaping unit; and

[0280] A third substrate is provided with a second signal processing unit configured to process the signal output from the waveform shaping unit.

[0281] (Configuration 18)

[0282] The photoelectric conversion device according to any one of Configurations 1 to 17, wherein the second signal processing unit includes a counter configured to count the signal output from the waveform shaping unit.

[0283] (Configuration 19)

[0284] The photoelectric conversion device according to any one of Configurations 1 to 18,

[0285] The charging unit includes a metal oxide semiconductor transistor, namely a MOS transistor, and

[0286] Wherein, a clock signal is input to the gate of the MOS transistor of the charging unit.

[0287] (Configuration 20)

[0288] A photoelectric conversion system, comprising:

[0289] The photoelectric conversion device according to any one of Configurations 1 to 19; and

[0290] A signal processing unit is configured to generate an image using the signal output from the photoelectric conversion device.

[0291] (Configuration 21)

[0292] A moving body, comprising the photoelectric conversion device according to any one of Configurations 1 to 19, the moving body comprising:

[0293] A control unit is configured to control movement of the moving body using the signal output from the photoelectric conversion device.

[0294] According to the present invention, it is possible to provide a photoelectric conversion device that solves the problem that occurs in a standby state in which a charging unit and a power source are disconnected.

[0295] While the present invention has been described with reference to exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. The scope of the following claims is to be accorded the broadest interpretation so as to encompass all such modifications and equivalent structures and functions.

Claims

1. A photoelectric conversion device, comprising: an avalanche photodiode having a first terminal and a second terminal; a first power source connected to the first terminal; a second power source connected to the second terminal; a charging unit configured to control a voltage of the first terminal; a voltage control unit connected to the first terminal and configured to control a voltage of the first terminal according to a voltage of the first terminal; as well as A third power supply is connected to the voltage control unit.

2. The photoelectric conversion device according to claim 1, wherein The voltage of the third power supply is a voltage between the voltage of the first power supply and the voltage of the second power supply.

3. The photoelectric conversion device according to claim 1, wherein The voltage of the third power supply is equal to the voltage of the first power supply.

4. The photoelectric conversion device according to claim 1, in, The voltage control unit includes a metal oxide semiconductor transistor, namely a MOS transistor, wherein one terminal of the MOS transistor is connected to the first terminal, and The other terminal of the MOS transistor is connected to the third power source.

5. The photoelectric conversion device according to claim 4, wherein The gate of the MOS transistor is connected to the first terminal.

6. The photoelectric conversion device according to claim 5, wherein The MOS transistor is a P-type MOS transistor.

7. The photoelectric conversion device according to claim 5, wherein The MOS transistor is an N-type MOS transistor.

8. The photoelectric conversion device according to claim 1, in, The voltage control unit includes a diode, wherein one terminal of the diode is connected to the first terminal, and The other terminal of the diode is connected to the third power source.

9. The photoelectric conversion device according to claim 8, in, The one terminal of the diode is a cathode, and Wherein, the other terminal of the diode is an anode.

10. The photoelectric conversion device according to claim 8, in, The voltage control unit further comprises a metal oxide semiconductor transistor, namely a MOS transistor, wherein one terminal of the MOS transistor is connected to the first terminal, and The other terminal of the MOS transistor is connected to the third power source via the diode.

11. The photoelectric conversion device according to claim 10, wherein The gate of the MOS transistor is connected to the first terminal.

12. The photoelectric conversion device according to claim 11, wherein The MOS transistor is a P-type MOS transistor.

13. The photoelectric conversion device according to claim 11, wherein The MOS transistor is an N-type MOS transistor.

14. The photoelectric conversion device according to claim 1, wherein The first terminal is a cathode of the avalanche photodiode.

15. The photoelectric conversion device according to claim 1, wherein The first terminal is an anode of the avalanche photodiode.

16. The photoelectric conversion device according to claim 1, further comprising a waveform shaping unit connected to the first terminal, in, The waveform shaping unit is connected to the voltage control unit.

17. The photoelectric conversion device according to claim 16, further comprising: a first substrate on which the avalanche photodiode is disposed; A second substrate, on which a first signal processing unit is disposed, wherein the first signal processing unit includes the charging unit, the voltage control unit and the waveform shaping unit; as well as A third substrate is provided with a second signal processing unit configured to process the signal output from the waveform shaping unit.

18. The photoelectric conversion device according to claim 17, wherein The second signal processing unit includes a counter configured to count the signal output from the waveform shaping unit.

19. The photoelectric conversion device according to claim 1, in, The charging unit includes a metal oxide semiconductor transistor (MOS transistor), and Wherein, a clock signal is input to the gate of the MOS transistor of the charging unit.

20. A photoelectric conversion system comprising: The photoelectric conversion device according to any one of claims 1 to 19; as well as A signal processing unit is configured to generate an image using the signal output from the photoelectric conversion device.

21. A moving body comprising the photoelectric conversion device according to any one of claims 1 to 19, the moving body comprising: A control unit is configured to control movement of the moving body using the signal output from the photoelectric conversion device.

Images