Array Sensor

Abstract

This invention provides an array sensor that can implement time filtering functionality while suppressing an increase in power consumption. [Solution] The array sensor 1 comprises a plurality of detection regions 10 arranged in one or two dimensions. Each detection region 10 has a plurality of sub-regions 11, 12. Each of the plurality of sub-regions 11, 12 has a photodetector portion including a gate electrode, a source electrode, a drain electrode, and a photoelectric conversion portion. The photoelectric conversion portion includes a two-dimensional layered material electrically connected to the source electrode and the drain electrode. In the photodetector portion, a current flows between the source electrode and the drain electrode according to the magnitude of the voltage applied to the gate electrode and the intensity of the light incident on the photoelectric conversion portion. The plurality of sub-regions 11, 12 have different time response characteristics. In each detection region 10, the signals from the plurality of sub-regions 11, 12 are combined and output as an output signal.

Description

Technical Field

[0006] , ,

[0001] The present invention relates to an array sensor.

Background Art

[0002] For example, Patent Document 1 describes a pixel device for an image sensor that generates an image. This pixel device is provided with an exposure measurement device, a circuit that transmits an exposure measurement result and a pixel device address to an evaluation circuit asynchronously by event control, and a luminance change detection circuit connected to the evaluation circuit. When the luminance change detection circuit detects a luminance change, it sends a signal to start the exposure measurement device and the circuit that transmits the exposure measurement result and the address asynchronously by event control.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the above-described pixel device, when a luminance change is detected, a start signal is sent according to the luminance change. On the other hand, for an image sensor, there may be a case where a function of a time filter (for example, a frequency bandpass filter) for extracting a specific temporal change is required. The function of the time filter can be realized, for example, by processing the output from a light receiving element by a circuit such as an FPGA (Field Programmable Gate Array). However, in this case, there is a risk that the power consumption will increase.

[0005] Therefore, an object of the present invention is to provide an array sensor that can realize the function of a time filter while suppressing an increase in power consumption.

Means for Solving the Problems

[0006] The array sensor of the present invention is [1] an array sensor comprising a plurality of detection regions arranged in one or two dimensions, each of the plurality of detection regions having a plurality of sub-regions, each of the plurality of sub-regions having a photoreceiving element portion including a gate electrode, a source electrode, a drain electrode, and a photoelectric conversion unit, the photoelectric conversion unit comprising a two-dimensional layered material electrically connected to the source electrode and the drain electrode, in the photoreceiving element portion a current flows between the source electrode and the drain electrode according to the magnitude of the voltage applied to the gate electrode and the intensity of the light incident on the photoelectric conversion unit, the plurality of sub-regions having different time response characteristics from each other, and in each of the plurality of detection regions the signals from the plurality of sub-regions are combined and output as an output signal.

[0007] In this array sensor, each detection region has multiple sub-regions, and the photoelectric conversion section of the photodetector in each sub-region contains a two-dimensional layered material, and the multiple sub-regions have different time response characteristics. Then, in each detection region, the signals from the multiple sub-regions are combined and output as an output signal. By combining the signals from multiple sub-regions with different time response characteristics and outputting them as an output signal, each detection region can be given the function of a time filter. This makes it possible to suppress the increase in power consumption compared to, for example, when the time filter function is implemented by a circuit such as an FPGA located downstream of the sensor. Therefore, with this array sensor, it is possible to realize the function of a time filter while suppressing the increase in power consumption.

[0008] The array sensor of the present invention may also be [2] "the array sensor according to [1], wherein the two-dimensional layered material comprises a transition metal dichalcogenide." In this case, since the transition metal dichalcogenide has a band gap, the photoelectric conversion unit can be suitably configured.

[0009] The array sensor of the present invention may also be [3] "the array sensor according to [1] or [2], wherein the plurality of sub-regions consist of two sub-regions having different time response characteristics." In this case, it becomes possible to configure one detection region to be small, and it becomes possible to increase the number of detection regions per unit area and improve spatial resolution.

[0010] The array sensor of the present invention may also be [4] "the array sensor according to [1] or [2], wherein the plurality of sub-regions include three or more sub-regions having different time response characteristics from each other." In this case, it is possible to realize a more precise (complex) time filter. Furthermore, if the time response characteristics of the plurality of sub-regions are made different by, for example, varying the magnitude of the voltage applied to the gate electrode, the optical responsiveness (gain) may also differ among the plurality of sub-regions, but this array sensor can realize the function of a time filter while taking into account the differences in gain.

[0011] The array sensor of the present invention may also be [5] "the array sensor according to [1] or [2], wherein the plurality of sub-regions include a plurality of first sub-regions and a plurality of second sub-regions, the time response characteristics of the plurality of first sub-regions differ from the time response characteristics of the plurality of second sub-regions, and the plurality of first sub-regions and the plurality of second sub-regions are arranged alternately along each of two mutually orthogonal directions." In this case, the plurality of sub-regions can be arranged so as to be less affected by the direction of the edge of the object to be detected.

[0012] The array sensor of the present invention may also be [6] "an array sensor according to any one of [1] to [5] in which, when signals from the plurality of sub-regions are combined and output as an output signal in each of the plurality of detection regions, a portion of the signals from a portion of the plurality of sub-regions are excluded and the signals from the plurality of sub-regions are combined and output as an output signal." In this case, when the gains differ among the plurality of sub-regions, the function of a time filter can be realized while taking into account the differences in gains.

[0013] The array sensor of the present invention may also be [7] "the array sensor according to any one of [1] to [6], wherein the plurality of sub-regions have different time response characteristics when voltages of different magnitudes are applied to the gate electrodes." In this case, for example, the structure of the photoelectric conversion section of each sub-region may be the same, which simplifies the structure and simplifies the manufacturing process.

[0014] The array sensor of the present invention may also be [8] "the array sensor according to any one of [1] to [7], wherein the plurality of sub-regions include a first sub-region and a second sub-region having different time response characteristics, a first wiring is electrically connected to the gate electrode of the photodetector in the first sub-region, and a second wiring, electrically separated from the first wiring, is electrically connected to the gate electrode of the photodetector in the second sub-region." In this case, voltages of different magnitudes can be applied to the gate electrode of the photodetector in the first sub-region and the gate electrode of the photodetector in the second sub-region via the first wiring and the second wiring, thereby making the time response characteristics of the first sub-region and the second sub-region different.

[0015] The array sensor of the present invention may also be [9] "the array sensor according to any one of [1] to [8], wherein the plurality of sub-regions include a first sub-region and a second sub-region having different time response characteristics, and the area of ​​the light-receiving surface of the photo-receiving element in the first sub-region is different from the area of ​​the light-receiving surface of the photo-receiving element in the second sub-region." In this case, the function of a time filter can be realized while adjusting the gain between the plurality of sub-regions by the area of ​​the light-receiving surface of the photo-receiving element.

[0016] The array sensor of the present invention may also be

[10] "the array sensor according to any one of [1] to [9], wherein the plurality of sub-regions include a first sub-region and a second sub-region, and the first sub-region and the second sub-region have different time response characteristics due to the different structures of the photoelectric conversion unit." In this case, the time response characteristics of the first sub-region and the second sub-region can be made different by different structures of the photoelectric conversion unit.

[0017] The array sensor of the present invention may also be the array sensor according to

[10] , wherein the number of layers of the two-dimensional layered material in the photoelectric conversion unit in the first sub-region is different from the number of layers of the two-dimensional layered material in the photoelectric conversion unit in the second sub-region. In this case, by making the number of layers of the two-dimensional layered material in the photoelectric conversion unit in the first sub-region and the second sub-region different, the time response characteristics of the first sub-region and the second sub-region can be made different.

[0018] The array sensor of the present invention may also be the array sensor according to

[10] or

[11] , wherein the material of the two-dimensional layered material of the photoelectric conversion unit in the first sub-region is different from the material of the two-dimensional layered material of the photoelectric conversion unit in the second sub-region. In this case, by making the materials of the two-dimensional layered material of the photoelectric conversion unit in the first sub-region and the second sub-region different, the time response characteristics of the first sub-region and the second sub-region can be made different.

[0019] The array sensor of the present invention may also be the array sensor described in any of [1] to

[12] ,

[13] "the array sensor described in any of [1] to

[12] , wherein the plurality of detection regions include a first detection region and a second detection region, each of the first detection region and the second detection region includes a first sub-region and a second sub-region having different time response characteristics, the operating mode of the array sensor includes a first mode and a second mode, in which the signals from the first sub-region and the second sub-region in each of the first detection region are combined and output as an output signal, and in the second mode, the signal from the first sub-region of the first detection region and the signal from the second sub-region of the second detection region are combined and output as an output signal." In this case, by switching between the first mode and the second mode to operate the array sensor, output signals with shifted detection ranges can be obtained. This makes it possible to obtain information for realizing the function of a spatial filter by comparing, for example, the signal obtained in the first mode with the signal obtained in the second mode.

[0020] The array sensor of the present invention may also be

[14] "an array sensor according to any of [1] to

[13] , wherein in each of a plurality of arrangement regions arranged along a predetermined direction, a first detection region, a second detection region, and a third detection region constituting the plurality of detection regions are arranged in this order from one side to the other in the predetermined direction, and an output signal is output from each of the plurality of arrangement regions, wherein the output signal from one of the arrangement regions is a signal obtained by combining the signal from the second detection region of the one arrangement region, the signal from the first detection region or third detection region of the arrangement region adjacent to the one arrangement region on the one side, and the signal from the first detection region or third detection region of the arrangement region adjacent to the one arrangement region on the other side." In this case, the function of a spatial filter can be realized.

[0021] The array sensor of the present invention may be the "array sensor described in

[14] , wherein the output signal from the one arrangement region is a signal obtained by combining the signal from the second detection region of the one arrangement region, the signal from the first detection region of the arrangement region adjacent to the one arrangement region on the one side, and the signal from the third detection region of the arrangement region adjacent to the one arrangement region on the other side". In this case, the function of the spatial filter can be more preferably realized.

[0022] The array sensor of the present invention may be the "array sensor according to any one of [1] to

[15] , wherein an output signal is output from the plurality of detection regions when changing from a bright state in which light is incident on the photoelectric conversion unit to a dark state in which no light is incident on the photoelectric conversion unit, and no output signal is output from the plurality of detection regions when changing from the dark state to the bright state". In this case, the amount of information can be reduced as compared with the case where both the output when changing from the dark state to the bright state and the output when changing from the bright state to the dark state are output. As a result, only a desired output signal can be extracted, and subsequent data processing can be facilitated.

[0023] The array sensor of the present invention may be the "array sensor according to any one of [1] to

[15] , wherein an output signal is output from the plurality of detection regions when changing from a dark state in which no light is incident on the photoelectric conversion unit to a bright state in which light is incident on the photoelectric conversion unit, and no output signal is output from the plurality of detection regions when changing from the bright state to the dark state". In this case, the amount of information can be reduced as compared with the case where both the output when changing from the dark state to the bright state and the output when changing from the bright state to the dark state are output. As a result, only a desired output signal can be extracted, and subsequent data processing can be facilitated.

Advantages of the Invention

[0024] According to the present invention, it is possible to provide an array sensor that can realize the function of a time filter while suppressing an increase in power consumption.

Brief Description of the Drawings

[0025] [Figure 1] It is a configuration diagram of the array sensor according to the embodiment. [Figure 2] (a) and (b) are cross-sectional views showing examples of the light receiving element portion. [Figure 3] (a), (b) and (c) are cross-sectional views showing examples of the light receiving element portion. [Figure 4] (a) is a graph showing an example of the time response characteristic of the first sub-region, and (b) is a graph showing an example of the time response characteristic of the second sub-region. [Figure 5] (a) is a graph showing an example of the output signal from the detection region, and (b) is a graph showing an example of the frequency response characteristic of the detection region. [Figure 6] (a) is a graph showing an example of the time response characteristic of the first sub-region, and (b) is a graph showing an example of the time response characteristic of the second sub-region. [Figure 7] (a) is a graph showing an example of the output signal from the detection region, and (b) is a graph showing an example of the frequency response characteristic of the detection region. <00001​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​ [Figure 18] (a) and (b) are diagrams or graphs illustrating the configuration for realizing a spatial filter. [Figure 19] (a) and (b) are diagrams illustrating the configuration for realizing a spatial filter. [Figure 20] (a) and (b) are diagrams or graphs illustrating the configuration for realizing a spatial filter. [Figure 21] (a) and (b) are diagrams or graphs illustrating the configuration for realizing a spatial filter. [Figure 22] This is a diagram illustrating the configuration for implementing a spatial filter. [Figure 23] (a) and (b) are diagrams illustrating the configuration for realizing a spatial filter. [Figure 24] This is a diagram showing the configuration of the array sensor in the fifth modified example. [Figure 25] This graph shows the output signal in the fifth modified example. [Figure 26] (a) and (b) are graphs showing the output signals in the fifth modified example. [Figure 27] (a) and (b) are cross-sectional views showing examples of the light-receiving element section. [Figure 28] (a) and (b) are diagrams illustrating the sixth modified example. [Figure 29] (a) and (b) are diagrams illustrating the sixth modified example. [Figure 30] This graph illustrates the seventh variation. [Modes for carrying out the invention]

[0026] Embodiments of the present invention will be described in detail below with reference to the drawings. In the following description, the same or equivalent elements will be denoted by the same reference numerals, and redundant explanations will be omitted.

[0027] As shown in Figure 1, the array sensor 1 comprises multiple detection regions 10 arranged in two dimensions. In this example, the array sensor 1 is an image sensor and detects light in each detection region 10. Each detection region 10 corresponds to a pixel in an image constructed based on the output signal from the image sensor.

[0028] In this example, the multiple detection regions 10 are arranged in a grid (matrix) and are aligned along mutually orthogonal first directions D1 and second directions D2. Each detection region 10 is formed, for example, in a rectangular shape.

[0029] Each detection region 10 has a first sub-region 11 and a second sub-region 12. In each detection region 10, the first sub-region 11 and the second sub-region 12 are aligned along a first direction D1. In each detection region 10, the first sub-region 11 is located on one side of the first direction D1, and the second sub-region 12 is located on the other side of the first direction D1. The first sub-region 11 and the second sub-region 12 are located adjacent to each other along the first direction D1. No first sub-region 11 and second sub-region 12 of another detection region 10 are located between the first sub-region 11 and the second sub-region 12 of one detection region. The first sub-region 11 and the second sub-region 12 are formed in the same rectangular shape with a long side along a second direction D2. Each of the first sub-region 11 and the second sub-region 12 has a light-receiving element section 13. In this example, the light-receiving element section 13 of the first sub-region 11 and the light-receiving element section 13 of the second sub-region 12 have the same configuration. The light-receiving element 13 will now be described with reference to Figures 2 and 3.

[0030] In the example shown in Figure 2(a), the photodetector 13 includes a substrate 21, a gate electrode 22, an insulating layer 23, a source electrode 24, a drain electrode 25, and a photoelectric conversion unit 26. The substrate 21 is formed of, for example, silicon dioxide (SiO2) or silicon. The substrate 21 of the photodetector 13 constituting the first sub-region 11 and the substrate 21 of the photodetector 13 constituting the second sub-region 12 may be different substrates or may be a common substrate. The gate electrode 22 is formed in layers on the substrate 21. The gate electrode 22, source electrode 24, and drain electrode 25 are formed of, for example, a metallic material such as titanium or nickel. The insulating layer 23 is formed on the gate electrode 22 on the side opposite to the substrate 21. The insulating layer 23 is formed of, for example, silicon dioxide or alumina (Al2O3).

[0031] The source electrode 24 and drain electrode 25 are formed on the insulating layer 23 on the side opposite to the substrate 21. The source electrode 24 and drain electrode 25 are spaced apart so as to be electrically isolated from each other. In this example, the first sub-region 11 and the second sub-region 12 have rectangular photoelectric conversion sections 26 of the same area. In this example, the entire photoelectric conversion section 26 is optically exposed, and the entire surface of the photoelectric conversion section 26 is a light-receiving surface (an effective area capable of converting incident light into an electrical signal). In Figure 1, the light-receiving surfaces of the first sub-region 11 and the second sub-region 12 are shown by hatching. The first sub-region 11 and the second sub-region 12 have rectangular light-receiving surfaces of the same area. The thickness of the photoelectric conversion section 26 is approximately 0.1 nm to 10 nm as an example. The size of the photoelectric conversion section 26 in plan view (viewed from a direction perpendicular to the light-receiving surface) is approximately 1 μm to 10 μm in length and width as an example. In this embodiment, the thickness of the photoelectric conversion unit 26 is smaller than the thickness of each of the substrate 21, gate electrode 22, insulating layer 23, source electrode 24, drain electrode 25, and the floating gate electrode 28, which will be described later. In this example, the photoelectric conversion unit 26 consists of a two-dimensional layered material 27. The two-dimensional layered material 27 is formed on the insulating layer 23 so as to be located between the source electrode 24 and the drain electrode 25, and is electrically connected to the source electrode 24 and the drain electrode 25. Note that a two-dimensional layered material may be used as the material for the electrodes (gate electrode 22, source electrode 24, drain electrode 25) or the insulating layer (insulating layer 23, insulating layer 29, which will be described later). In that case, the thickness of the photoelectric conversion unit 26 may be equal to the thickness of the electrodes or insulating layer, or smaller than the thickness of the electrodes or insulating layer.

[0032] The two-dimensional layered material 27 is composed of a material having a crystalline structure in which the interatomic bonds are closed within the layers, and the interlayers are bonded only by weak van der Waals forces. In a two-dimensional layered material, a layered structure is formed by atomic layers that are strongly chemically bonded (covalently) in two dimensions and weakly chemically bonded (van der Waals bonds). In this example, the two-dimensional layered material 27 is composed of molybdenum disulfide (MoS2), which is a transition metal dichalcogenide (TMD). A transition metal dichalcogenide has a layered structure in which a transition metal layer (molybdenum: Mo, tungsten: W, etc.) is sandwiched between two chalcogen (sulfur: S, selenium: Se, or tellurium: Te, etc.) layers. The two-dimensional layered material 27 can be any material capable of realizing the photogating effect described later, and may include, for example, graphene, black phosphorus, MXene, etc. The transition metal dichalcogenide constituting the two-dimensional layered material 27 may be tungsten selenide (WSe2).

[0033] The two-dimensional layered material 27 (photoelectric conversion unit 26) is positioned to be exposed to the outside on the opposite side from the substrate 21, and light is incident on the two-dimensional layered material 27. A protective layer that can transmit detection light may be placed on the two-dimensional layered material 27. The light-receiving element unit 13 has a phototransistor structure, and in the light-receiving element unit 13, a current flows between the source electrode 24 and the drain electrode 25 depending on the magnitude of the voltage applied to the gate electrode 22 and the intensity of the light incident on the two-dimensional layered material 27. That is, when light is incident on the two-dimensional layered material 27 with a voltage (gate voltage) applied to the gate electrode 22, a current flows between the source electrode 24 and the drain electrode 25 depending on the magnitude of the gate voltage and the intensity of the incident light. This current flowing between the source electrode 24 and the drain electrode 25 is output as an output signal from the light-receiving element unit 13 (first sub-region 11 and second sub-region 12).

[0034] In the photodetector 13, the apparent gate voltage is modulated according to the intensity of light incident on the two-dimensional layered material 27 due to the photogating effect occurring in the two-dimensional layered material 27. The photogating effect is a phenomenon in which an additional electric field is generated when carriers (electrons and holes) generated by light are trapped within the two-dimensional layered material 27. The electric field generated by the trapped carriers shifts the transfer characteristic curve of the transistor (modulating the apparent gate voltage). This photogating effect allows the time response of the photodetector 13 to be controlled.

[0035] The light-receiving element 13 may be configured as shown in Figure 2(b), Figure 3(a), Figure 3(b), or Figure 3(c). In the example of Figure 2(b), the light-receiving element 13 further comprises a floating gate electrode 28 formed on an insulating layer 23, and an insulating layer 29 formed on the floating gate electrode 28. The floating gate electrode 28 is formed of the same metallic material as, for example, the gate electrode 22, source electrode 24, and drain electrode 25. The insulating layer 29 is formed of, for example, silicon dioxide or alumina. In the example of Figure 2(b), the presence of the floating gate electrode 28 allows voltage to be retained on the floating gate electrode 28, thereby reducing power consumption.

[0036] In the examples of Figures 2(a) and 2(b), the gate electrode 22 has a single-gate structure, whereas in the examples of Figures 3(a), 3(b), and 3(c), the gate electrode 22 has a split-gate structure. In the example of Figure 3(a), the gate electrode 22 is composed of two parts 22a, 22a. The two parts 22a, 22a are spaced apart so as to be electrically isolated from each other. For example, voltages of the same magnitude but with different positive and negative values ​​(e.g., 5V and -5V) are applied to parts 22a, 22a. Note that it is sufficient for a potential difference to exist between parts 22a, 22a; it is not necessarily required that voltages of the same magnitude but with different positive and negative values ​​be applied to parts 22a, 22a.

[0037] The example in Figure 3(b) differs from the example in Figure 3(a) in that the light-receiving element 13 further comprises a floating gate electrode 28 and an insulating layer 29. The example in Figure 3(c) differs from the example in Figure 3(b) in that the floating gate electrode 28 is composed of two parts 28a, 28a that are spaced apart from each other so as to be electrically isolated. In any of the examples in Figures 2(a) to 3(c), the light-receiving element 13 is configured to have a phototransistor structure.

[0038] As shown in Figure 1, in the array sensor 1, signals from the first sub-region 11 and the second sub-region 12 are combined and output as an output signal in each detection region 10. In this example, the output of the first sub-region 11 and the output of the second sub-region 12 are electrically connected by wiring formed within the array sensor 1, and the output signal from the first sub-region 11 is added while the output signal from the second sub-region 12 is subtracted, resulting in the sum of the signals from the first sub-region 11 and the second sub-region 12. The output signal from each detection region 10 is output as the signal of the corresponding pixel in the output image. In this example, a signal with positive polarity is output from the first sub-region 11, and a signal with negative polarity is output from the second sub-region 12. In each detection region 10, a signal with positive polarity is output from at least one of the multiple sub-regions, and a signal with negative polarity is output from at least one of the multiple sub-regions. For example, if three sub-regions are formed in each detection region 10, then either a positive polarity signal is output from two sub-regions and a negative polarity signal is output from one sub-region, or a negative polarity signal is output from two sub-regions and a positive polarity signal is output from one sub-region. However, it is not possible for only signals of either positive or negative polarity to be output from all three sub-regions.

[0039] In the array sensor 1, the first sub-region 11 and the second sub-region 12 have different time response characteristics. In this example, the first sub-region 11 and the second sub-region 12 have different time response characteristics because voltages of different magnitudes are applied to the gate electrode 22. In a phototransistor structure configured with a photoelectric conversion unit 26 containing a two-dimensional layered material 27, the time response characteristics can be changed by changing the magnitude of the gate voltage.

[0040] Figure 4(a) is a graph showing an example of the time response characteristics of the first sub-region 11, and Figure 4(b) is a graph showing an example of the time response characteristics of the second sub-region 12. In each graph, the output from the first sub-region 11 and the second sub-region 12 is shown as black dots, the intensity of light incident on the first sub-region 11 and the second sub-region 12 is shown as white dots, and the time period during which light is incident is shown as hatching. These points are the same in Figures 5-7, 13, 17, 19, 20, 23-25, and 29, which will be described later. In the example shown in Figure 4, the time response characteristics of the first sub-region 11 and the second sub-region 12 are different because the gate voltages of the first sub-region 11 and the second sub-region 12 are different from each other. In the example shown in Figure 4, the response of the first sub-region 11 is faster than the response of the second sub-region 12. When light is incident, the output in the first sub-region 11 increases sharply, while the output in the second sub-region 12 increases more gradually than in the first sub-region 11. Furthermore, when light is no longer incident, the output in the first sub-region 11 decreases sharply, while the output in the second sub-region 12 decreases more gradually than in the first sub-region 11.

[0041] Figure 5(a) shows the output signal from the detection region 10 obtained by combining the signals from the first sub-region 11 and the second sub-region 12 shown in Figures 4(a) and 4(b) (by subtracting the output of the second sub-region 12 from the output of the first sub-region 11). Figure 5(b) shows the frequency response characteristics of the detection region 10 in this case. As shown in Figure 5(b), in this example, the detection region 10 can be configured to have high response characteristics in a specific frequency band, and the detection region 10 can be given the function of a frequency bandpass filter. That is, the detection region 10 can be given the function of a time filter that extracts specific temporal changes. In this example, the bandpass filter function of the detection region 10 is realized by combining the first sub-region 11 and the second sub-region 12, which function as low-pass filters individually, and subtracting the output of the second sub-region 12 from the output of the first sub-region 11. More specifically, a bandpass filter function is achieved by combining low-pass filters with different characteristics, using a first sub-region 11 that has high response characteristics in a higher frequency band and a second sub-region 12 that has high response characteristics in a lower frequency band.

[0042] Figures 6 and 7 are diagrams or graphs illustrating another example. In this example as well, the time response characteristics of the first sub-region 11 and the second sub-region 12 differ because their gate voltages are different. As shown in Figure 6, the response of the first sub-region 11 is faster than the response of the second sub-region 12. As shown in Figure 7(b), in this example, the response peak is in a higher frequency band than in the cases of Figures 4 and 5. In this way, the characteristics of the time filter can be changed by adjusting the gate voltage to adjust the time response characteristics of the first sub-region 11 and the second sub-region 12.

[0043] Figures 8 to 12 are diagrams illustrating wiring examples. In the array sensor 1 of the embodiment, as shown in Figure 8, the first sub-regions 11 of each detection region 10 are electrically connected by a first wiring 31, and the second sub-regions 12 of each detection region 10 are electrically connected by a second wiring 32. More specifically, the first wiring 31 is electrically connected to the gate electrode 22 of the photodetector 13 in each first sub-region 11, and the second wiring 32 is electrically connected to the gate electrode 22 of the photodetector 13 in each second sub-region 12. The second wiring 32 is electrically isolated from the first wiring 31. This allows different gate voltages to be applied to the gate electrode 22 of the first sub-region 11 and the second sub-region 12. Figure 9 shows a circuit diagram corresponding to Figure 8.

[0044] As shown in Figure 10, a first wiring 31 may be electrically connected to the first sub-region 11 of each detection region 10, and a second wiring 32 may be electrically connected to the second sub-region 12 of each detection region 10. In this case, the gate voltage applied to the gate electrode 22 of the first sub-region 11 and the second sub-region 12 of each detection region 10 can be set individually. For example, this configuration may be advantageous when there are manufacturing variations between multiple detection regions 10. Alternatively, this configuration may be advantageous when advanced applications are required, such as when the response speed of the detection region 10 is to be changed according to its position within the detection surface of the sensor.

[0045] As shown in the modified example described later, when the gate voltage of the same magnitude is applied to the gate electrodes 22 of the first sub-region 11 and the second sub-region 12, the first sub-region 11 and the second sub-region 12 of each detection region 10 may be electrically connected by a common first wiring 31, as shown in Figure 11. In this case, the wiring and circuit can be simplified. Figure 12 shows a circuit diagram corresponding to Figure 11. In the examples of Figures 9 and 12, the source electrode 24 is connected to ground, but a voltage may be applied to the source electrode 24, or a voltage set individually, similar to the gate voltage, may be applied. In the example of Figure 12, for example, by using two-dimensional layered material 27 of different materials in the first sub-region 11 and the second sub-region 12, signals with different polarities can be output from the first sub-region 11 and the second sub-region 12 even when a common gate voltage is applied. [Mechanism of Action and Effects]

[0046] In the array sensor 1, each detection region 10 has a first sub-region 11 and a second sub-region 12 (multiple sub-regions), and the photoelectric conversion unit 26 of the light-receiving element section 13 of the first sub-region 11 and the second sub-region 12 includes a two-dimensional layered material 27, and the first sub-region 11 and the second sub-region 12 have different time response characteristics. Then, in each detection region 10, the signals from the first sub-region 11 and the second sub-region 12 are combined and output as an output signal. By combining the signals from the first sub-region 11 and the second sub-region 12, which have different time response characteristics, and outputting them as an output signal, each detection region 10 can be given a time filter function. As a result, the increase in power consumption can be suppressed compared to, for example, when the time filter function is realized by a circuit such as an FPGA provided downstream of the sensor. Therefore, with this array sensor 1, it is possible to realize a time filter function while suppressing the increase in power consumption. Furthermore, since the light-receiving element section 13 of each detection region 10 has a phototransistor structure, the time response characteristics can be changed by adjusting the gate voltage, and an image can be output that detects an object moving at any desired speed.

[0047] The photoelectric conversion section 26 of the light-receiving element section 13 includes a two-dimensional layered material 27. The photoelectric conversion section 26 including the two-dimensional layered material 27 has the characteristic that its bipolar output characteristics and time response characteristics can be adjusted according to the gate voltage, so that any time filter can be realized with a simple configuration. Bipolar output characteristics are characteristics in which positive and negative responses to the same optical input can be controlled by the gate voltage. Furthermore, the two-dimensional layered material 27 includes a transition metal dichalcogenide. This makes it possible to suitably realize the characteristics that allow for adjustment of bipolar output characteristics and time response characteristics according to the gate voltage. In addition, since the transition metal dichalcogenide has a band gap, the photoelectric conversion section 26 can be suitably configured.

[0048] Each detection region 10 has only two sub-regions 11 and 12, which have different time response characteristics. This makes it possible to configure each detection region 10 to be small, and to increase the number of detection regions 10 per unit area, thereby improving spatial resolution.

[0049] The first sub-region 11 and the second sub-region 12 have different time response characteristics because voltages of different magnitudes are applied to the gate electrode 22. As a result, the structure of the photoelectric conversion section 26 in the first sub-region 11 and the second sub-region 12 may be the same, thus simplifying the structure and facilitating the manufacturing process.

[0050] The first wiring 31 is electrically connected to the gate electrode 22 of the photodetector 13 in the first sub-region 11, and the second wiring 32, which is electrically isolated from the first wiring 31, is electrically connected to the gate electrode 22 of the photodetector 13 in the second sub-region 12. As a result, voltages of different magnitudes can be applied to the gate electrode 22 of the photodetector 13 in the first sub-region 11 and the gate electrode 22 of the photodetector 13 in the second sub-region 12 via the first wiring 31 and the second wiring 32, thereby making the time response characteristics of the first sub-region 11 and the second sub-region 12 different. [Differentiation]

[0051] In the first modified example shown in Figure 13, the area of ​​the light-receiving surface of the photodetector 13 in the first sub-region 11 is different from the area of ​​the light-receiving surface of the photodetector 13 in the second sub-region 12. In this example, the area of ​​the light-receiving surface of the photodetector 13 in the first sub-region 11 is smaller than the area of ​​the light-receiving surface of the photodetector 13 in the second sub-region 12. Even with this first modified example, the function of a time filter can be realized while suppressing an increase in power consumption, similar to the embodiment described above. Furthermore, the function of a time filter can be realized while adjusting the optical response (gain) between the first sub-region 11 and the second sub-region 12 by adjusting the area of ​​the light-receiving surface of the photodetector 13.

[0052] This point will be explained with reference to Figure 14. When the time response characteristics of the first sub-region 11 and the second sub-region 12 are made different by varying the magnitude of the gate voltage applied to the gate electrode 22, there is a possibility that the optical response (gain) will differ between the first sub-region 11 and the second sub-region 12. This is also true when the time response characteristics of the first sub-region 11 and the second sub-region 12 are made different by varying the structure of the photoelectric conversion unit 26, as will be described later. For example, in the example in Figure 14, the output of the first sub-region 11 shown in the left graph rises to near a value of 250, while the output of the second sub-region 12 shown in the center graph rises only to near a value of 150. In this case, as shown in the right graph, an offset occurs in the output signal from the detection region 10 obtained by combining the signals from the first sub-region 11 and the second sub-region 12, as indicated by arrow A1. Note that in the example in Figure 14, the area of ​​the light-receiving surface of the first sub-region 11 and the second sub-region 12 is the same.

[0053] In this regard, in the first modified example, by making the area of ​​the light-receiving surface of the light-receiving element 13 different, the gain can be adjusted between the first sub-region 11 and the second sub-region 12 so that the offset described above does not occur. As a result, the outputs of the sub-regions cancel each other out for inputs outside the desired frequency range, so that signals in the desired frequency range can be selectively output (resulting in sparse output characteristics) and the amount of information can be reduced.

[0054] In the second modified example shown in Figure 15, each detection region 10 has a third sub-region 19 in addition to the first sub-region 11 and the second sub-region 12. The time response characteristics of the first sub-region 11, the second sub-region 12, and the third sub-region 19 are different from each other. The first sub-region 11, the second sub-region 12, and the third sub-region 19 are arranged in this order along the first direction D1. The area of ​​the first sub-region 11 and the area of ​​the third sub-region 19 are equal, and the areas of the first sub-region 11 and the third sub-region 19 are smaller than the area of ​​the second sub-region 12. In this example, the output signals from the first sub-region 11 are added and the output signals from the second sub-region 12 and the third sub-region 19 are subtracted, and the signals from the first sub-region 11, the second sub-region 12, and the third sub-region 19 are summed and output as the output signal from each detection region 10. Note that the areas of the first sub-region 11, the second sub-region 12, and the third sub-region 19 may be the same. In this example, the output from the first sub-region 11 is added, and the outputs from the second sub-region 12 and the third sub-region 19 are subtracted. However, the combination of addition and subtraction can be changed arbitrarily. For example, the outputs from the first sub-region 11 and the second sub-region 12 may be added, and the output from the third sub-region 19 may be subtracted. However, each detection region 10 must have at least one sub-region where the output is added and one sub-region where the output is subtracted.

[0055] This second modification also allows for the implementation of a time filter function while suppressing an increase in power consumption, similar to the above embodiment. Furthermore, it enables the implementation of a more precise (complex) time filter. Additionally, the time filter function can be implemented while considering the gain differences between the first sub-region 11, the second sub-region 12, and the third sub-region 19. For example, the gains can be adjusted between the first sub-region 11, the second sub-region 12, and the third sub-region 19 so that the offset described above does not occur.

[0056] In the third modified example shown in Figure 16, each detection region 10 has multiple (two in this example) first sub-regions 11 and multiple (two in this example) second sub-regions 12. The time response characteristics of the two first sub-regions 11 are different from the time response characteristics of the two second sub-regions 12. The two first sub-regions 11 and the two second sub-regions 12 are arranged alternately along the mutually orthogonal first direction D1 and second direction D2, respectively. This third modified example also allows for the realization of the time filter function while suppressing an increase in power consumption, similar to the above embodiment. Furthermore, multiple sub-regions can be arranged to be less affected by the direction of the edge of the object to be detected. Note that each detection region 10 may have three or more first sub-regions 11 and three or more second sub-regions 12. For example, three or more first sub-regions 11 and three or more second sub-regions 12 may be arranged alternately along the first direction D1 and second direction D2, respectively. Furthermore, being less affected by the direction of the edge of the object being detected means that it becomes less likely for conditions to occur within the detection area 10 such as light incident only on the first sub-area 11 or only on the second sub-area 12.

[0057] In the fourth modified example shown in Figure 17, in each detection region 10, a wire with a resistor R is electrically connected to the wire connected to the output of the second sub-region 12. As a result, a portion of the current (output signal) output from the second sub-region 12 flows through the resistor R. The current flowing through the resistor R is excluded and not included in the output signal of the detection region 10. Thus, in the fourth modified example, when the signals from the first sub-region 11 and the second sub-region 12 are combined and output as an output signal in each detection region 10, a portion of the signal from the second sub-region 12 is excluded, and the signals from the first sub-region 11 and the second sub-region 12 are combined and output as an output signal.

[0058] This fourth modification also allows for the implementation of a time filter function while suppressing an increase in power consumption, similar to the above embodiment. Furthermore, when the gains differ between multiple sub-regions, the time filter function can be implemented while taking into account the differences in gains. For example, the gain between the first sub-region 11 and the second sub-region 12 can be adjusted by adjusting the magnitude of the resistor R to exclude a portion of the signal from the second sub-region 12 so that the offset described above does not occur. In the example of Figure 17, a portion of the signal from the second sub-region 12 is excluded at the same time that the signals from the first sub-region 11 and the second sub-region 12 are combined, but a portion of the signal from the second sub-region 12 may be excluded before or after the signals from the first sub-region 11 and the second sub-region 12 are combined.

[0059] The array sensor 1 may be equipped with a spatial filtering function in addition to the temporal filtering function. The configuration for realizing the spatial filter will be explained with reference to Figures 18 to 23. As shown in Figure 18(a), the array sensor 1 has five pixels, A, B, C, D, and E, and it is assumed that light shines on pixels D and E and then disappears. In this case, as shown in Figure 18(b), if a positive output is generated at pixels D and E where light was shone, and a negative output is generated at pixel C which is not shone with light and is adjacent to pixels D and E where light was shone, then it can be considered that a spatial filter that emphasizes edges based on the presence or absence of light has been realized.

[0060] As shown in Figure 19(a), when implementing a spatial filter using digital processing, for example, convolutional filtering can be implemented so that the output signal is calculated considering the outputs of adjacent pixels. In Figure 19(a), for example, if the output of pixel C is set to 1.0, the outputs of adjacent pixels B and D are multiplied by -0.2 and added to the output signal. To implement a spatial filter within the array sensor 1, as shown in Figure 19(b), each of pixels A to E can be divided into three subpixels, and the outputs of the subpixels can be combined to obtain a result similar to convolutional filtering. The area of ​​the subpixels is set to correspond to the weighting in convolutional filtering. Note that the weighting (coefficient 0.2 in the above example) may be adjusted as appropriate.

[0061] When the example in Figure 19(b) is associated with the array sensor 1, in the example in Figure 19(b), a first detection area 10X, a second detection area 10Y, and a third detection area 10Z are arranged in this order from one side of the first direction D1 to the other in each of the multiple (five in this example) arrangement areas 50 that are aligned along a predetermined direction (hereinafter, as an example, the first direction D1). An output signal is then output from each arrangement area 50. Here, the output signal from one arrangement area 50 (for example, the arrangement area 50 corresponding to pixel C) is a signal that combines the signal from the second detection area 10Y of the one arrangement area 50, the signal from the third detection area 10Z of the arrangement area 50 adjacent to the one arrangement area 50 on one side of the first direction D1 (for example, the arrangement area 50 corresponding to pixel B), and the signal from the first detection area 10X of the arrangement area 50 adjacent to the one arrangement area 50 on the other side of the first direction D1 (for example, the arrangement area 50 corresponding to pixel D). This enables the implementation of spatial filtering functionality.

[0062] On the other hand, because there are intensity differences between subpixels, the spatial filter may not function adequately in the example described above. For example, when light is shone at the positions indicated by hatching in Figures 20(a) and 20(b), a positive output is generated at pixel D', while no negative output appears at pixel C', and the spatial filter does not function adequately (Figure 20(b)).

[0063] Therefore, as shown in Figure 21(a), it is conceivable to combine the outputs of subpixels. If we associate the example in Figure 21(a) with the array sensor 1, in the example in Figure 21(a), the output signal from one arrangement region 50 (for example, the arrangement region 50 corresponding to pixel C) is a signal that combines the signal from the second detection region 10Y of the first arrangement region 50, the signal from the first detection region 10X of the arrangement region 50 adjacent to the first arrangement region 50 on one side of the first direction D1 (for example, the arrangement region 50 corresponding to pixel B), and the signal from the third detection region 10Z of the arrangement region 50 adjacent to the first arrangement region 50 on the other side of the first direction D1 (for example, the arrangement region 50 corresponding to pixel D). This makes it possible to more effectively realize the function of the spatial filter. For example, when light is irradiated at the same position as in Figure 20(a), a negative output appears at pixel C', as shown in Figure 21(b), unlike the example in Figure 20, and the function of the spatial filter is effectively performed.

[0064] As described above, in the array sensor 1, each detection region 10 has a first sub-region 11 and a second sub-region 12. Figure 22 shows the specific configuration of the array sensor 1 with the spatial filtering function of Figure 21 implemented. In Figure 22, only the wiring connected to pixels B', C', and D' is shown, and other wiring is omitted. Figure 23(a) is a diagram focusing only on pixel C' in Figure 22. As shown in Figure 23(b), various spatial filtering functions can be implemented by adjusting the polarity and weight of the output from the sub-regions. Figure 23 shows the output b1 from the first sub-region 11 of the first detection region 10X of pixel B, the output b2 from the second sub-region 12 of the first detection region 10X of pixel B, the output c1 from the first sub-region 11 of the second detection region 10Y of pixel C, the output c2 from the second sub-region 12 of the second detection region 10Y of pixel C, the output d1 from the first sub-region 11 of the third detection region 10Z of pixel D, and the output d2 from the second sub-region 12 of the third detection region 10Z of pixel D. For example, when the edge enhancement function described above is implemented as a spatial filter, outputs b1, c2, and d2 are made negative (subtracted), and outputs b2, c1, and d1 are made positive (added). In this configuration, the outputs from the first detection region 10X and the third detection region 10Z have opposite polarity to the output from the second detection region 10Y. In general digital processing, edge enhancement processing such as first-order differential filters and second-order differential filters is sometimes performed by summing adjacent pixels with opposite polarities, and this configuration can achieve the same effect using a similar principle. When implementing a blurring filter (e.g., Gaussian filter, averaging filter, etc.) that blurs the edges of the detected object as a spatial filter, outputs b1, c1, and d1 are considered positive (added), and outputs b2, c2, and d2 are considered negative (subtracted). In this configuration, the outputs from the first detection region 10X, the second detection region 10Y, and the third detection region 10Z have the same polarity. In general digital processing, blurring processing such as Gaussian filters and averaging filters is sometimes performed by summing adjacent pixels with the same polarity, and this configuration can achieve the same effect using a similar principle. In addition to these examples, any spatial filter function can be implemented by adjusting the polarity and weight of the outputs from the sub-regions.By implementing a spatial filtering function in the array sensor 1 in addition to the temporal filtering function in each detection region 10, a spatiotemporal filtering function can be realized.

[0065] Figures 24 to 26 illustrate the fifth modified array sensor 1 in which a spatial filtering function is implemented. While Figures 18 to 23 illustrate an example in which a spatial filtering function is implemented in a one-dimensionally arranged arrangement region 50, in the fifth modified example, the spatial filtering function (edge ​​enhancement function) is implemented in a two-dimensionally arranged arrangement region 50.

[0066] As shown in Figure 24, in the fifth modified example, multiple placement regions 50 are arranged along the first direction D1 and the second direction D2, respectively. Each placement region 50 contains a pair of first detection regions 10X, a second detection region 10Y, and a pair of third detection regions 10Z, arranged in this order from one side to the other in the first direction D1. The pair of first detection regions 10X are arranged along the second direction D2, and the pair of third detection regions 10Z are arranged along the second direction D2. The pair of first detection regions 10X face the pair of third detection regions 10Z in the first direction D1, with the second detection region 10Y in between. In the example in Figure 24, the outputs of the first detection region 10X, the second detection region 10Y, and the third detection region 10Z, enclosed by thick solid lines, are combined and output as the output signal of placement region 50A. Furthermore, the outputs of the first detection region 10X, the second detection region 10Y, and the third detection region 10Z, which are enclosed by thick dashed lines, are combined and output as the output signal for the placement region 50B. As shown in Figure 25, a positive signal is generated in the second detection region 10Y, while negative signals are generated in the first detection region 10X and the third detection region 10Z. As shown in Figure 26(b), a positive output is generated in the placement region 50A where light is irradiated, while a negative output is generated in the placement region 50B where light is not irradiated, as shown in Figure 26(a), thus realizing the edge enhancement function.

[0067] In the above embodiment and its modifications, the photodetector elements 13 of the first sub-region 11 and the second sub-region 12 have the same configuration, and the time response characteristics of the first sub-region 11 and the second sub-region 12 differ because voltages of different magnitudes are applied to the gate electrodes 22 of the first sub-region 11 and the second sub-region 12. However, the time response characteristics of the first sub-region 11 and the second sub-region 12 may differ because the structures of the photoelectric conversion units 26 of the first sub-region 11 and the second sub-region 12 are different. In this case, the gate voltages applied to the gate electrodes 22 of the first sub-region 11 and the second sub-region 12 may be the same or different. Even with such modifications, the function of a time filter can be realized while suppressing an increase in power consumption, similar to the above embodiment.

[0068] For example, the number of layers of the two-dimensional layered material 27 in the photoelectric conversion unit 26 in the first sub-region 11 may differ from the number of layers of the two-dimensional layered material 27 in the photoelectric conversion unit 26 in the second sub-region 12. In the example shown in Figure 27(a), the photoelectric conversion unit 26 has one layer of the two-dimensional layered material 27, while in the example shown in Figure 27(b), the photoelectric conversion unit 26 has three layers of the two-dimensional layered material 27. By making the number of layers of the two-dimensional layered material 27 in the photoelectric conversion unit 26 different in the first sub-region 11 and the second sub-region 12, the time response characteristics of the first sub-region 11 and the second sub-region 12 can be made different. The thickness of one layer of the two-dimensional layered material 27 in the photoelectric conversion unit 26 is, for example, about 0.1 nm to 1 nm, and the thickness of the photoelectric conversion unit 26 can be increased by increasing the number of layers.

[0069] Alternatively, or in addition to the above, the material of the two-dimensional layered material 27 of the photoelectric conversion unit 26 in the first sub-region 11 may be different from the material of the two-dimensional layered material 27 of the photoelectric conversion unit 26 in the second sub-region 12. For example, the two-dimensional layered material 27 of the photoelectric conversion unit 26 in the first sub-region 11 may be formed of molybdenum disulfide, and the two-dimensional layered material 27 of the photoelectric conversion unit 26 in the second sub-region 12 may be formed of tungsten selenide. By making the materials of the two-dimensional layered material 27 of the photoelectric conversion unit 26 in the first sub-region 11 and the second sub-region 12 different in this way, the time response characteristics of the first sub-region 11 and the second sub-region 12 can also be made different. When three layers of two-dimensional layered material 27 are provided as shown in Figure 27(b), the materials of the three layers of two-dimensional layered material 27 may be the same or different from each other.

[0070] The structures of the photoelectric conversion sections 26 in the first sub-region 11 and the second sub-region 12 may be made different from each other by means other than varying the number of layers or the material of the two-dimensional layered material 27. For example, the time response characteristics of the first sub-region 11 and the second sub-region 12 can be made different by varying the material of the insulating layer 23 that contacts the two-dimensional layered material 27. Thus, varying the structure of the photoelectric conversion section 26 includes varying the material of the layers that the two-dimensional layered material 27 contacts.

[0071] Figures 28 and 29 illustrate a sixth modified example. As shown in Figure 28, the array sensor 1 of the sixth modified example has a plurality of first detection regions 10A and a plurality of second detection regions 10B as detection regions 10. The plurality of first detection regions 10A and the plurality of second detection regions 10B are arranged alternately along the first direction D1. Although only three detection regions 10 arranged along the first direction D1 are shown in Figure 28, in reality there may be four or more detection regions 10 (first detection regions 10A and second detection regions 10B) arranged along the first direction D1. Also, although the rows of detection regions 10 are shown in two columns along the second direction D2 in Figure 28, in reality there may be three or more columns of detection regions 10 along the second direction D2.

[0072] As shown in Figure 28, the first sub-region 11 of the second detection region 10B is electrically connected via wiring to the second sub-region 12 of the adjacent first detection region 10A on one side of the first direction D1, and the second sub-region 12 of the second detection region 10B is electrically connected via wiring to the first sub-region 11 of the adjacent first detection region 10A on the other side of the first direction D1. If four or more detection regions 10 are arranged, the first sub-region 11 of the first detection region 10A is electrically connected via wiring to the second sub-region 12 of the adjacent second detection region 10B on one side of the first direction D1, and the second sub-region 12 of the first detection region 10A is electrically connected via wiring to the first sub-region 11 of the adjacent second detection region 10B on the other side of the first direction D1.

[0073] The sixth modified example of the array sensor 1 includes a first mode shown in Figure 28(a) and a second mode shown in Figure 28(b). The first mode is the same as the operation mode in the above embodiment and modified example. As shown in Figure 28(a), in the first mode, signals from the first sub-region 11 and the second sub-region 12 are combined and output as an output signal in each first detection region 10A and each second detection region 10B. In Figure 28, wiring that outputs an output signal in each operation mode is shown with a solid line, and wiring that does not output an output signal is shown with a dashed line.

[0074] As shown in Figure 28(b), in the second mode, the signal from the first sub-region 11 of the first detection region 10A and the signal from the second sub-region 12 of the second detection region 10B are combined and output as an output signal, and the signal from the second sub-region 12 of the first detection region 10A and the signal from the first sub-region 11 of the second detection region 10B are combined and output as an output signal. In other words, in the second mode, in adjacent first detection regions 10A and second detection regions 10B, a pseudo-sub-region 10C is formed by the first sub-region 11 of the first detection region 10A and the second sub-region 12 of the second detection region 10B, and in adjacent first detection regions 10A and second detection regions 10B, a pseudo-sub-region 10C is formed by the second sub-region 12 of the first detection region 10A and the first sub-region 11 of the second detection region 10B.

[0075] As shown in Figure 29, switching between the first and second modes can be achieved, for example, by a switch S. As shown in Figure 29(a), in the first mode, the switch S connects the wiring so that the outputs of the first sub-region 11 and the second sub-region 12 in each first detection region 10A and each second detection region 10B are connected to each other. As shown in Figure 29(b), in the second mode, the switch S connects the wiring so that the signal from the first sub-region 11 of the first detection region 10A and the signal from the second sub-region 12 of the second detection region 10B are combined and output as an output signal, and the signal from the second sub-region 12 of the first detection region 10A and the signal from the first sub-region 11 of the second detection region 10B are combined and output as an output signal.

[0076] This sixth modification also allows for the implementation of a time filter function while suppressing an increase in power consumption, similar to the above embodiment. Furthermore, by switching between the first and second modes to operate the array sensor 1, output signals with different detection ranges can be acquired. This allows for the acquisition of information necessary to implement a spatial filter function, for example, by comparing the signal acquired in the first mode with the signal acquired in the second mode.

[0077] As a seventh modification, when the state changes from a bright state, where light is incident on the photoelectric conversion unit 26 (two-dimensional layered material 27), to a dark state, where no light is incident on the photoelectric conversion unit 26, an output signal is output from each detection region 10. On the other hand, when the state changes from a dark state to a bright state, an output signal does not need to be output from each detection region 10.

[0078] This point will be explained with reference to Figure 30. The graph on the left of Figure 30 shows an example of the time response characteristics of the first sub-region 11, and the graph in the center of Figure 30 shows an example of the time response characteristics of the second sub-region 12. In this example, the gate voltages of the first sub-region 11 and the second sub-region 12 are different, resulting in different time response characteristics for the first sub-region 11 and the second sub-region 12. However, while the time response characteristics (fall times) of the first sub-region 11 and the second sub-region 12 are different when changing from a bright state to a dark state, the time response characteristics (rise times) of the first sub-region 11 and the second sub-region 12 are the same when changing from a dark state to a bright state (indicated by the dashed line A2 in the figure). In this case, as shown in the graph on the right of Figure 30, the output signal from the detection region 10, obtained by combining the signals from the first sub-region 11 and the second sub-region 12, does not show a waveform corresponding to the change from a dark state to a bright state. For example, in such cases, the amount of information can be reduced by outputting an output signal from each detection area 10 only when the state changes from a light state to a dark state, as in the seventh modified example. In other words, the amount of information can be reduced compared to the case where both the output when the state changes from a dark state to a light state and the output when the state changes from a light state to a dark state are output. As a result, only the desired output signal can be extracted, making subsequent data processing easier. Alternatively, depending on the application, it may be sufficient to detect only the change from a light state to a dark state, and in such cases, the configuration of the seventh modified example can also be suitably applied. Note that "no output signal is output from the detection area when the state changes from a dark state to a light state (or from a dark state to a light state)" means that a signal at a level that can be considered an output signal is not output from the detection area, and this includes cases where a signal with a very small noise level is output from the detection area. In other words, it means that no output signal is substantially output from the detection area.

[0079] As another variation, an output signal may be output from each detection region 10 when the state changes from dark to light, while no output signal may be output from each detection region 10 when the state changes from light to dark. This configuration can be suitably applied when the time response characteristics of the first sub-region 11 and the second sub-region 12 are different when the state changes from dark to light, but the time response characteristics of the first sub-region 11 and the second sub-region 12 are the same when the state changes from light to dark. In this case as well, the amount of information can be reduced compared to the case where both the output when the state changes from dark to light and the output when the state changes from light to dark are output. As a result, only the desired output signal can be extracted, making subsequent data processing easier.

[0080] The present invention is not limited to the embodiments and modifications described above. For example, the materials and shapes of each component are not limited to those described above, but can be made from a variety of materials and shapes. In the embodiments described above, the array sensor 1 had a plurality of detection regions 10 arranged in two dimensions, but the array sensor 1 may have only a plurality of detection regions 10 arranged in one dimension (in a single column). Each detection region 10 may have three or more subregions, and the time response characteristics of the three or more subregions may be different from each other. The three or more subregions may include two or more subregions that have the same time response characteristics. [Explanation of symbols]

[0081] 1...Array sensor, 10...Detection area, 10A, 10X...First detection area, 10B, 10Y...Second detection area, 10Z...Third detection area, 11...First sub-area, 12...Second sub-area, 13...Photodetector section, 22...Gate electrode, 24...Source electrode, 25...Drain electrode, 26...Photoelectric conversion section, 27...Two-dimensional layered material, 31...First wiring, 32...Second wiring, 50...Placement area.

Claims

1. It comprises multiple detection regions arranged in one or two dimensions, Each of the aforementioned plurality of detection regions has a plurality of sub-regions, Each of the plurality of sub-regions has a photodetector portion including a gate electrode, a source electrode, a drain electrode, and a photoelectric conversion portion, the photoelectric conversion portion includes a two-dimensional layered material electrically connected to the source electrode and the drain electrode, and in the photodetector portion, a current flows between the source electrode and the drain electrode in accordance with the magnitude of the voltage applied to the gate electrode and the intensity of the light incident on the photoelectric conversion portion. The plurality of sub-regions have different time response characteristics from each other. An array sensor in which signals from multiple sub-regions are combined and output as an output signal in each of the multiple detection regions.

2. The array sensor according to claim 1, wherein the two-dimensional layered material comprises a transition metal dichalcogenide.

3. The array sensor according to claim 1 or 2, wherein the plurality of sub-regions consist of two sub-regions having different time response characteristics.

4. The array sensor according to claim 1 or 2, wherein the plurality of sub-regions include three or more sub-regions having different time response characteristics from each other.

5. The plurality of sub-regions include a plurality of first sub-regions and a plurality of second sub-regions, and the time response characteristics of the plurality of first sub-regions differ from the time response characteristics of the plurality of second sub-regions. The array sensor according to claim 1 or 2, wherein the plurality of first sub-regions and the plurality of second sub-regions are arranged alternately along each of two mutually orthogonal directions.

6. The array sensor according to claim 1 or 2, wherein when signals from the plurality of sub-regions are combined and output as an output signal in each of the plurality of detection regions, a portion of the signals from a portion of the plurality of sub-regions are excluded and the signals from the plurality of sub-regions are combined and output as an output signal.

7. The array sensor according to claim 1 or 2, wherein the plurality of sub-regions have different time response characteristics when voltages of different magnitudes are applied to the gate electrode.

8. The plurality of sub-regions include a first sub-region and a second sub-region having different time response characteristics from each other. The array sensor according to claim 1 or 2, wherein a first wiring is electrically connected to the gate electrode of the light-receiving element in the first sub-region, and a second wiring, electrically separated from the first wiring, is electrically connected to the gate electrode of the light-receiving element in the second sub-region.

9. The plurality of sub-regions include a first sub-region and a second sub-region having different time response characteristics from each other. The array sensor according to claim 1 or 2, wherein the area of ​​the light-receiving surface of the light-receiving element in the first sub-region is different from the area of ​​the light-receiving surface of the light-receiving element in the second sub-region.

10. The plurality of sub-regions include a first sub-region and a second sub-region, The array sensor according to claim 1 or 2, wherein the first sub-region and the second sub-region have different time response characteristics due to the different structures of the photoelectric conversion unit.

11. The array sensor according to claim 10, wherein the number of layers of the two-dimensional layered material in the photoelectric conversion unit in the first sub-region is different from the number of layers of the two-dimensional layered material in the photoelectric conversion unit in the second sub-region.

12. The array sensor according to claim 10, wherein the material of the two-dimensional layered material in the photoelectric conversion section in the first sub-region is different from the material of the two-dimensional layered material in the photoelectric conversion section in the second sub-region.

13. The plurality of detection regions include a first detection region and a second detection region. Each of the first detection region and the second detection region includes a first sub-region and a second sub-region having different time response characteristics from each other. The operating modes of the array sensor include a first mode and a second mode. In the first mode, the signals from the first sub-region and the second sub-region are combined and output as an output signal in the first detection region and the second detection region, respectively. In the second mode, the signal from the first sub-region of the first detection region and the signal from the second sub-region of the second detection region are combined and output as an output signal, as described in claim 1 or 2.

14. In each of the multiple arrangement regions aligned along a predetermined direction, the first detection region, the second detection region, and the third detection region constituting the multiple detection regions are arranged in this order from one side to the other in the predetermined direction. The array sensor according to claim 1 or 2, wherein an output signal is output from each of the plurality of arrangement regions, and the output signal from one of the arrangement regions is a signal obtained by combining the signal from the second detection region of the one arrangement region, the signal from the first detection region or the third detection region of the arrangement region adjacent to the one arrangement region on one side, and the signal from the first detection region or the third detection region of the arrangement region adjacent to the one arrangement region on the other side.

15. The array sensor according to claim 14, wherein the output signal from the first arrangement region is a signal obtained by combining the signal from the second detection region of the first arrangement region, the signal from the first detection region of the arrangement region adjacent to the first arrangement region on one side, and the signal from the third detection region of the arrangement region adjacent to the first arrangement region on the other side.

16. The array sensor according to claim 1 or 2, wherein when the state changes from a bright state in which light is incident on the photoelectric conversion unit to a dark state in which light is not incident on the photoelectric conversion unit, an output signal is output from the plurality of detection regions, and when the state changes from the dark state to the bright state, no output signal is output from the plurality of detection regions.

17. The array sensor according to claim 1 or 2, wherein when the state changes from a dark state where no light is incident on the photoelectric conversion unit to a bright state where light is incident on the photoelectric conversion unit, an output signal is output from the plurality of detection regions, and when the state changes from the bright state to the dark state, no output signal is output from the plurality of detection regions.

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