Detection device

Abstract

To provide a detection device capable of improving detection accuracy.SOLUTION: A detection device includes a substrate, a plurality of photodiodes arranged on the substrate and stacked on the substrate in the following order, a lower electrode, a lower buffer layer, an active layer, an upper buffer layer, and an upper electrode, a plurality of signal lines respectively electrically connected to the lower electrodes of the plurality of photodiodes, a detection circuit connected to the plurality of photodiodes via the plurality of signal lines, and a shielding layer arranged between the plurality of signal lines in a planar view.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a detection device. [Background technology]

[0002] Optical sensors capable of detecting fingerprint patterns and vein patterns are known (for example, Patent Document 1). Among such optical sensors, sensors having multiple photodiodes in which an organic semiconductor material is used as an active layer are known. The organic semiconductor material is disposed between a lower electrode and an upper electrode, and a signal line for outputting a detection signal to a detection circuit is electrically connected to the lower electrode of the photodiode. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2009-32005 Summary of the Invention [Problem to be solved by the invention]

[0004] If the parasitic capacitance formed between multiple signal lines or between adjacent signal lines and the lower electrode increases, there is a possibility that potential fluctuations (also called crosstalk) may occur between the multiple signal lines or between adjacent signal lines and the lower electrode, which may result in errors in the detection signal output from the photodiode to the detection circuit.

[0005] An object of the present invention is to provide a detection device that can improve detection accuracy. [Means for solving the problem]

[0006] A detection device according to one embodiment of the present invention includes a substrate, a plurality of photodiodes arranged on the substrate and stacked in the following order on the substrate: a lower electrode, a lower buffer layer, an active layer, an upper buffer layer, and an upper electrode, a plurality of signal lines electrically connected to the respective lower electrodes of the plurality of photodiodes, a detection circuit electrically connected to the plurality of photodiodes via the plurality of signal lines, and a shielding layer arranged between the plurality of signal lines in a planar view.

[0007] A detection device according to one embodiment of the present invention includes a substrate, a plurality of photodiodes arranged on the substrate and stacked in the following order on the substrate: a lower electrode, a lower buffer layer, an active layer, an upper buffer layer, and an upper electrode, a plurality of signal lines electrically connected to the respective lower electrodes of the plurality of photodiodes, a detection circuit electrically connected to the plurality of photodiodes via the plurality of signal lines, and a shielding layer arranged between the plurality of lower electrodes in a planar view.

[0008] A detection device according to one embodiment of the present invention includes a substrate, a plurality of photodiodes arranged on the substrate and stacked in the following order on the substrate: a lower electrode, a lower buffer layer, an active layer, an upper buffer layer, and an upper electrode, a plurality of signal lines electrically connected to the lower electrodes of the plurality of photodiodes, a detection circuit electrically connected to the plurality of photodiodes via the plurality of signal lines, and a shielding layer arranged between the signal lines and the lower electrode in a planar view. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a plan view showing a detection device according to a first embodiment. [Figure 2] FIG. 2 is a cross-sectional view taken along line II-II' of FIG. [Figure 3] FIG. 3 is a cross-sectional view taken along line III-III' in FIG. [Figure 4] FIG. 4 is a plan view showing a detection device according to a first modified example. [Figure 5] FIG. 5 is a cross-sectional view taken along line VV' in FIG. [Figure 6] FIG. 6 is a cross-sectional view taken along line VI-VI' in FIG. [Figure 7] FIG. 7 is a cross-sectional view schematically showing a signal line and a shield layer of a detection device according to a second modification. [Figure 8] FIG. 8 is a cross-sectional view schematically showing a signal line and a shield layer of a detection device according to a third modified example. [Figure 9] FIG. 9 is a cross-sectional view schematically showing a signal line and a shield layer of a detection device according to a fourth modified example. [Figure 10] FIG. 10 is a side view showing an example of use of the detection device according to the first embodiment for measuring biological information. [Figure 11] FIG. 11 is a plan view showing a detection device according to the second embodiment. [Figure 12] FIG. 12 is a cross-sectional view taken along the line XII-XII' in FIG. [Figure 13] FIG. 13 is a plan view showing a detection device according to the third embodiment. [Figure 14] FIG. 14 is a circuit diagram showing a detection device according to the third embodiment. [Figure 15] FIG. 15 is an enlarged plan view showing the plurality of photodiodes and the shield layer of FIG. [Figure 16] FIG. 16 is a cross-sectional view taken along the line XVI-XVI' in FIG. [Figure 17] FIG. 17 is an enlarged plan view showing a plurality of photodiodes and a shield layer of a detection device according to a fifth modification. [Figure 18] FIG. 18 is an enlarged plan view showing a plurality of photodiodes and a shield layer of a detection device according to a sixth modified example. [Figure 19] FIG. 19 is a cross-sectional view taken along the line XIX-XIX' in FIG. [Figure 20] FIG. 20 is a plan view showing a detection device according to a seventh modified example. [Figure 21] FIG. 21 is a cross-sectional view taken along line XXI-XXI' of FIG. DETAILED DESCRIPTION OF THE INVENTION

[0010] Modes (embodiments) for carrying out the present invention will be described in detail with reference to the drawings. The present disclosure is not limited to the contents described in the following embodiments. Furthermore, the components described below include those that can be easily imagined by a person skilled in the art and those that are substantially identical. Furthermore, the components described below can be combined as appropriate. Note that the disclosure is merely an example, and any appropriate modifications that a person skilled in the art can easily make while maintaining the gist of the present disclosure are naturally included within the scope of the present disclosure. Furthermore, for clarity of explanation, the drawings may schematically depict the width, thickness, shape, etc. of each part compared to the actual embodiment. However, these are merely examples and are not intended to limit the interpretation of the present disclosure. Furthermore, in this disclosure and each figure, elements similar to those previously described with reference to the preceding figures may be designated by the same reference numerals, and detailed descriptions may be omitted as appropriate.

[0011] In this specification and claims, when expressing an aspect of placing another structure on top of a certain structure, the term "on top" is used, unless otherwise specified, to include both a case in which another structure is placed directly on top of a certain structure so as to be in contact with the certain structure, and a case in which another structure is placed above a certain structure via yet another structure.

[0012] (First embodiment) 1 is a plan view showing a detection device according to the first embodiment. As shown in Fig. 1, the detection device 1 includes a substrate 21, a plurality of photodiodes PD, a plurality of signal lines SL, a plurality of shield layers 26, and a control circuit 122.

[0013] The substrate 21 has a detection area AA and a peripheral area GA. The detection area AA is an area in which a plurality of photodiodes PD are provided. The peripheral area GA is an area between the periphery of the detection area AA and the edge of the substrate 21, and is an area in which the plurality of photodiodes PD are not provided. The plurality of signal lines SL and the control circuit 122 are provided in the peripheral area GA of the substrate 21.

[0014] In the following description, the first direction Dx is a direction in a plane parallel to the substrate 21. The second direction Dy is a direction in a plane parallel to the substrate 21, and is a direction perpendicular to the first direction Dx. The second direction Dy may intersect the first direction Dx without being perpendicular thereto. The third direction Dz is a direction perpendicular to the first direction Dx and the second direction Dy. The third direction Dz is a normal direction to the substrate 21. Furthermore, "planar view" refers to the positional relationship when viewed from a direction perpendicular to the substrate 21.

[0015] The detection device 1 has a plurality of photodiodes PD as optical sensor elements. Each photodiode PD outputs an electrical signal corresponding to the light irradiated thereon. More specifically, the photodiodes PD are organic photodiodes (OPDs) that use organic semiconductors. The plurality of photodiodes PD are arranged side by side in the second direction Dy in the detection area AA.

[0016] The photodiodes PD each include a lower electrode 23 disposed below the organic semiconductor and an upper electrode 24 disposed above the organic semiconductor. The lower electrodes 23 are provided for each of the photodiodes PD and are arranged side by side in the second direction Dy in the detection area AA. The lower electrodes 23 are also arranged spaced apart in the second direction Dy. The upper electrode 24 is provided across the photodiodes PD and is continuous with the detection area AA. The configurations of the photodiodes PD, the lower electrodes 23, and the upper electrode 24 will be described later with reference to FIG. 2.

[0017] The signal lines SL are electrically connected to the respective lower electrodes 23 of the respective photodiodes PD. Specifically, in the example shown in FIG. 1 , lower electrodes 23-1, 23-2, ..., 23-8 are arranged in the second direction Dy corresponding to the respective photodiodes PD. The signal lines SL-1, SL-2, ..., SL-8 are connected to the respective lower electrodes 23-1, 23-2, ..., 23-8. In the following description, when it is not necessary to distinguish between the signal lines SL-1, SL-2, ..., SL-8, they will simply be referred to as signal lines SL. Furthermore, when it is not necessary to distinguish between the lower electrodes 23-1, 23-2, ..., 23-8, they will simply be referred to as lower electrodes 23.

[0018] Each of the multiple signal lines SL extends in a first direction Dx from a connection point with the lower electrode 23, bends in a second direction Dy, and extends in the second direction Dy along the arrangement direction of the multiple photodiodes PD. The portions of the multiple signal lines SL-1, SL-2, ..., SL-8 extending in the second direction Dy are arranged in the first direction Dx. The multiple signal lines SL are connected to a detection circuit 48 included in the control circuit 122. In other words, the detection circuit 48 is electrically connected to the lower electrodes 23 of the multiple photodiodes PD via the multiple signal lines SL.

[0019] The multiple shield layers 26 are arranged between the multiple signal lines SL in a plan view. Specifically, shield layers 26-1, 26-2, ..., 26-7 are arranged between the signal lines SL-1, SL-2, ..., SL-8, respectively. In the following description, when it is not necessary to distinguish between the shield layers 26-1, 26-2, ..., 26-7, they will be simply referred to as shield layer 26.

[0020] The multiple shield layers 26 include a first shield portion 26a extending in the second direction Dy and a second shield portion 26b connected to the first shield portion 26a and extending in the first direction Dx. The first shield portion 26a is disposed between the portions of the multiple signal lines SL that extend in the second direction Dy and extends along the signal lines SL. The second shield portion 26b is disposed between the portions of the multiple signal lines SL that extend in the first direction Dx and extends between the multiple lower electrodes 23 in a plan view.

[0021] The first shield portions 26a of the multiple shield layers 26 extend in the second direction Dy and are connected to a power supply circuit 123 included in the control circuit 122. The power supply circuit 123 supplies a reference voltage VCOM to the multiple shield layers 26. The reference voltage VCOM is a voltage signal having a fixed, predetermined potential. The reference voltage VCOM is, for example, a voltage signal having a potential equivalent to the sensor reference voltage COM supplied to the lower electrode 23. The power supply circuit 123 also supplies a sensor power supply signal VDDSNS to the upper electrode 24 of the photodiode PD.

[0022] The control circuit 122 (detection circuit 48 and power supply circuit 123) is disposed adjacent to the photodiodes PD in the second direction Dy in the peripheral area GA of the substrate 21. The control circuit 122 is a circuit that supplies control signals to the multiple photodiodes PD to control their detection operations. The multiple photodiodes PD output electrical signals corresponding to the light irradiated thereon as detection signals Vdet to the detection circuit 48. In this embodiment, the detection signals Vdet of the multiple photodiodes PD are output to the detection circuit 48 sequentially in a time-division manner. In other words, the multiple signal lines SL are electrically connected to the detection circuit 48 sequentially in a time-division manner. As a result, the detection device 1 detects information about the object to be detected based on the detection signals Vdet from the multiple photodiodes PD.

[0023] The control circuit 122 (detection circuit 48 and power supply circuit 123) is provided on the same substrate 21 as the multiple photodiodes PD, but is not limited to this. The control circuit 122 (detection circuit 48 and power supply circuit 123) may be provided on a separate control substrate connected to the substrate 21 via, for example, a flexible printed circuit board. The detection circuit 48 and the power supply circuit 123 may also be formed as separate circuits.

[0024] Although not shown in Fig. 1, the detection device 1 may have one or more light sources. The light source may be, for example, an inorganic light emitting diode (LED) or an organic light emitting diode (OLED).

[0025] Light emitted from the light source is reflected by the surface of the object to be detected, such as a finger, and enters multiple photodiodes PD. This allows the detection device 1 to detect a fingerprint by detecting the uneven shape of the surface of the finger or the like. Alternatively, the light emitted from the light source may be reflected inside the finger or the like or pass through the finger or the like and enter multiple photodiodes PD. This allows the detection device 1 to detect information about a living body inside the finger or the like. The information about a living body includes, for example, the pulse wave, pulse rate, and blood vessel image of the finger or palm. In other words, the detection device 1 may be configured as a fingerprint detection device that detects fingerprints, or a vein detection device that detects blood vessel patterns such as veins.

[0026] Next, a description will be given of the laminated structure of the photodiode PD and the shield layer 26. Fig. 2 is a cross-sectional view taken along line II-II' in Fig. 1.

[0027] In the following description, the direction perpendicular to the surface of the substrate 21, from the substrate 21 toward the sealing film 28, will be referred to as the "upper side" or simply "upper." The direction from the sealing film 28 toward the substrate 21 will be referred to as the "lower side" or simply "lower."

[0028] 2, the substrate 21 is an insulating substrate, and is made of, for example, glass or a resin material. The substrate 21 is not limited to a flat plate shape, and may have a curved surface. In this case, the substrate 21 may be a film-like resin.

[0029] The shield layer 26 is provided on the substrate 21. The shield layer 26 is formed, for example, of a metal wiring, and is formed of a material having better conductivity than the lower electrodes 23 of the photodiodes PD. The shield layer 26 is provided in a layer between the substrate 21 and the photodiodes PD in the third direction Dz. As described above, the second shield portions 26b of the shield layer 26 are located between the lower electrodes 23 of adjacent photodiodes PD. The insulating film 27 is provided on the substrate 21 to cover the shield layer 26. The insulating film 27 may be an inorganic insulating film or an organic insulating film.

[0030] The photodiode PD is provided on the insulating film 27. More specifically, the photodiode PD has a lower electrode 23, a lower buffer layer 32, an active layer 31, an upper buffer layer 33, and an upper electrode 24. In the photodiode PD, the lower electrode 23, the lower buffer layer 32 (hole transport layer), the active layer 31, the upper buffer layer 33 (electron transport layer), and the upper electrode 24 are stacked in this order in a direction perpendicular to the substrate 21.

[0031] The lower electrode 23 is an anode electrode of the photodiode PD and is made of a light-transmitting conductive material such as ITO (Indium Tin Oxide). The detection device 1 of this embodiment is formed as a bottom-light-receiving optical sensor in which light from the object to be detected passes through the substrate 21 and enters the photodiode PD.

[0032] The characteristics (for example, voltage-current characteristics and resistance value) of the active layer 31 change depending on the light irradiated thereon. An organic material is used as the material of the active layer 31. Specifically, the active layer 31 has a bulk heterostructure in which a p-type organic semiconductor and an n-type organic semiconductor, an n-type fullerene derivative (PCBM), are mixed. For example, low-molecular-weight organic materials such as C60 (fullerene), PCBM (phenyl C61-butyric acid methyl ester), CuPc (copper phthalocyanine), F16CuPc (fluorinated copper phthalocyanine), rubrene (5,6,11,12-tetraphenyltetracene), and PDI (perylene derivative) can be used as the active layer 31.

[0033] The active layer 31 can be formed by a vapor deposition method (dry process) using these low-molecular-weight organic materials. In this case, the active layer 31 may be, for example, a laminated film of CuPc and F16CuPc, or a laminated film of rubrene and C60. The active layer 31 can also be formed by a coating method (wet process). In this case, the active layer 31 is made of a material that combines the above-mentioned low-molecular-weight organic material with a high-molecular-weight organic material. Examples of high-molecular-weight organic materials that can be used include P3HT (poly(3-hexylthiophene)) and F8BT (F8-alt-benzothiadiazole). The active layer 31 can be a film in which P3HT and PCBM are mixed, or a film in which F8BT and PDI are mixed.

[0034] The lower buffer layer 32 is a hole transport layer, and the upper buffer layer 33 is an electron transport layer. The lower buffer layer 32 and the upper buffer layer 33 are provided to facilitate the holes and electrons generated in the active layer 31 reaching the lower electrode 23 or the upper electrode 24. The lower buffer layer 32 (hole transport layer) is directly in contact with the upper surface of the lower electrode 23, and is also provided in the region between adjacent lower electrodes 23. The active layer 31 is directly in contact with the upper surface of the lower buffer layer 32. The material of the hole transport layer is a metal oxide layer. Tungsten oxide (WO3), molybdenum oxide, etc. are used as the metal oxide layer.

[0035] The upper buffer layer 33 (electron transport layer) is directly on and in contact with the active layer 31, and the upper electrode 24 is directly on and in contact with the upper buffer layer 33. Ethoxylated polyethyleneimine (PEIE) is used as the material for the electron transport layer.

[0036] The materials and manufacturing methods of the lower buffer layer 32, the active layer 31, and the upper buffer layer 33 are merely examples, and other materials and manufacturing methods may be used. For example, the lower buffer layer 32 and the upper buffer layer 33 are not limited to single-layer films, and may be formed as multilayer films including an electron blocking layer and a hole blocking layer.

[0037] The upper electrode 24 is provided on the upper buffer layer 33. The upper electrode 24 is a cathode electrode of the photodiode PD, and is formed continuously over the entire detection area AA. In other words, the upper electrode 24 is provided continuously over the multiple photodiodes PD. The upper electrode 24 faces the multiple lower electrodes 23, with the lower buffer layer 32, active layer 31, and upper buffer layer 33 interposed therebetween. The upper electrode 24 is formed of a light-transmitting conductive material such as ITO or IZO.

[0038] The sealing film 28 is provided on the upper electrode 24. The sealing film 28 is made of an inorganic film such as a silicon nitride film or an aluminum oxide film, or a resin film such as acrylic. The sealing film 28 is not limited to a single layer, but may be a laminated film of two or more layers combining the inorganic film and the resin film. The sealing film 28 effectively seals the photodiode PD and can prevent moisture from entering from the upper surface side.

[0039] 3 is a cross-sectional view taken along the line III-III' in FIG. 1. As shown in FIG. 3, a plurality of signal lines SL are provided on a substrate 21. A plurality of shield layers 26 (first shield portions 26a) are provided on the substrate 21 in the same layer as the signal lines SL and are disposed between adjacent signal lines SL. In this embodiment, the signal lines SL and the shield layers 26 are alternately arranged in the first direction Dx, such as signal line SL-1, shield layer 26-1 (first shield portion 26a), signal line SL-2, shield layer 26-2 (first shield portion 26a), ... Note that the signal lines SL and the shield layers 26 are not limited to being provided directly on the substrate 21, and may be provided on the substrate 21 via one or more insulating films.

[0040] The insulating film 27 is provided on the substrate 21, covering the multiple signal lines SL and the multiple shield layers 26. In the region shown in Fig. 3, the photodiode PD is not provided, and a sealing film 28 is provided on the insulating film 27. The sealing film 28 is provided continuously across the detection region AA and the peripheral region GA.

[0041] As described above, the multiple shield layers 26 are disposed between adjacent signal lines SL and are supplied with the reference voltage VCOM. The shield layers 26 suppress the parasitic capacitance between the adjacent signal lines SL, thereby suppressing unintended capacitive coupling between the signal lines SL. Therefore, even if a potential difference occurs between the adjacent signal lines SL, fluctuations in the potential of the signal lines SL are suppressed.

[0042] For example, during a readout period (first readout period) of the photodiode PD, a detection signal Vdet1 detected by the photodiode PD-1 (see FIG. 1) is output to the detection circuit 48 via the signal line SL-1. During the next readout period (second readout period), a detection signal Vdet2 detected by the photodiode PD-2 (see FIG. 1) is output to the detection circuit 48 via the signal line SL-2. During the second readout period, readout of the photodiode PD-1 has already been completed, and the potential of the signal line SL-1 has dropped to near the reference voltage VCOM.

[0043] In this way, when the detection signals Vdet of the photodiodes PD are sequentially read out, the potential difference between adjacent signal lines SL may become large. As described above, in this embodiment, multiple shield layers 26 are provided, which suppresses fluctuations in the potential of adjacent signal lines SL and suppresses fluctuations in the detection signals Vdet output from the signal lines SL to the detection circuit 48.

[0044] 2, multiple shield layers 26 (second shield portions 26b) are disposed between adjacent lower electrodes 23, and a reference voltage VCOM is supplied to the shield layers 26. As a result, the shield layers 26 suppress parasitic capacitance between adjacent lower electrodes 23, and suppress unintended capacitive coupling between the lower electrodes 23. Therefore, even if a potential difference occurs between the lower electrodes 23 of adjacent photodiodes PD, fluctuations in the potential between adjacent photodiodes PD are suppressed. Therefore, fluctuations in the detection signal Vdet output from the photodiode PD to the detection circuit 48 via the signal line SL are suppressed. As described above, the detection device 1 of this embodiment can improve detection accuracy.

[0045] The reference voltage VCOM supplied to the multiple shield layers 26 is not limited to a voltage equivalent to the sensor reference voltage COM supplied to the lower electrode 23. The reference voltage VCOM may be any predetermined fixed voltage signal, and may be, for example, a voltage signal equivalent to the sensor power supply signal VDDSNS (sensor voltage) supplied to the upper electrode 24.

[0046] (First Modification) 4 is a plan view showing a detection device according to Modification 1. In the following description, the same components as those described in the above embodiment are denoted by the same reference numerals, and redundant description will be omitted.

[0047] As shown in FIG. 4, in the detecting device 1A according to the first modification, the shield layer 26A overlaps the multiple signal lines SL and is provided continuously across the multiple signal lines SL. More specifically, the shield layer 26A has a first shield portion 26Aa and multiple second shield portions 26Ab connected to the first shield portion 26Aa. The first shield portion 26Aa has a rectangular shape in a plan view and overlaps the multiple signal lines SL and is provided continuously across the multiple signal lines SL. In other words, at least a portion of the shield layer 26A (first shield portion 26Aa) is disposed between the multiple signal lines SL in a plan view.

[0048] The width of the first shield part 26Aa in the first direction Dx is larger than the overall width of the multiple signal lines SL (i.e., the width of signal lines SL-1 to SL-8 in the first direction Dx). The second shield part 26Ab is connected to the first shield part 26Aa, extends from the first shield part 26Aa in the first direction Dx in a plan view, and is provided between adjacent bottom electrodes 23 in the second direction Dy.

[0049] 5 is a cross-sectional view taken along the line V-V' in FIG. 4. As shown in FIG. 5, the insulating film 27 is provided on the substrate 21, covering the multiple signal lines SL. The first shield portion 26Aa of the shield layer 26A is provided on the insulating film 27. In other words, the shield layer 26A is provided in a layer above the multiple signal lines SL, and is provided continuously across the region overlapping the multiple signal lines SL and the region between adjacent signal lines SL (regions not overlapping the multiple signal lines SL). The sealing film 28 is provided on the insulating film 27, covering the shield layer 26A.

[0050] Fig. 6 is a cross-sectional view taken along line VI-VI' in Fig. 4. As shown in Fig. 6, the second shield portion 26Ab of the shield layer 26A is provided on an insulating film 27, in the same layer as the lower electrodes 23 of the photodiodes PD. The second shield portion 26Ab of the shield layer 26A is located between the lower electrodes 23 of adjacent photodiodes PD. The lower buffer layer 32 is provided to cover the multiple lower electrodes 23 and the second shield portion 26Ab.

[0051] In the first modified example, the first shield portion 26Aa of the shield layer 26A also reduces the parasitic capacitance between adjacent signal lines SL. Furthermore, the second shield portion 26Ab of the shield layer 26A also reduces the parasitic capacitance between adjacent lower electrodes 23. Furthermore, in the first modified example, the shield layer 26A is provided to cover the signal lines SL, thereby effectively blocking noise that enters the signal lines SL from the outside (the sealing film 28 side of the detection device 1). Because the first shield portion 26Aa of the shield layer 26A is provided in a different layer from the signal lines SL, the arrangement pitch of the signal lines SL can be made smaller compared to the first embodiment, thereby improving the degree of freedom in routing the signal lines SL. Furthermore, because the second shield portion 26Ab of the shield layer 26A is provided in the same layer as the lower electrodes 23 of the photodiodes PD, fluctuations in the potential between the lower electrodes 23 can be suppressed compared to the first embodiment.

[0052] (Second Modification) 7 is a cross-sectional view schematically showing the signal line and the shielding layer of the detection device according to the second modification. Note that the plan view of the detection device 1B according to the second modification is similar to FIG. 1, so repeated illustration is omitted.

[0053] 7, in the detecting device 1B according to the second modification, the shield layer 26B is provided on the insulating film 27 and is arranged between adjacent signal lines SL in a plan view. In other words, unlike the first modification described above, the first shield portion 26Ba of the shield layer 26B is not provided in a region overlapping with the multiple signal lines SL, but is provided in a region between the adjacent signal lines SL (a region not overlapping with the multiple signal lines SL).

[0054] The first shield parts 26Ba are each formed linearly along the signal lines SL, similar to the first shield parts 26a shown in Fig. 1. In the example shown in Fig. 7, the first shield parts 26Ba are arranged alternately in the first direction Dx as follows: signal line SL-1, shield layer 26B-1, signal line SL-2, shield layer 26B-2, signal line SL-3, shield layer 26B-3, signal line SL-4, and so on.

[0055] In the second modification, the area of ​​the shield layer 26B provided above the signal line SL is smaller than in the first modification described above, and therefore the capacitance formed between the signal line SL and the shield layer 26B is suppressed. Therefore, even when the shield layer 26B is provided, the time constant of the signal line SL is reduced, and it is possible to suppress an increase in the time required to read out the detection signal Vdet.

[0056] (Third Modification) 8 is a cross-sectional view schematically showing the signal line and the shielding layer of the detection device according to the third modification. Note that the plan view of the detection device 1C according to the third modification is similar to FIG. 4, and therefore will not be repeated.

[0057] 8, in a detecting device 1C according to the third modification, a shield layer 26C is provided in a layer between the substrate 21 and the signal lines SL in the third direction Dz. Specifically, the shield layer 26C is provided on the substrate 21. An insulating film 29 is provided to cover the shield layer 26C, and the multiple signal lines SL are provided on the insulating film 29. In the third modification, the shield layer 26C, the insulating film 29, the signal lines SL, the insulating film 27, and the sealing film 28 are stacked in this order on the substrate 21.

[0058] 4, the shield layer 26C overlaps the multiple signal lines SL and is provided continuously across the multiple signal lines SL. In other words, the shield layer 26C is provided in a layer below the multiple signal lines SL and is provided continuously across the region overlapping the multiple signal lines SL and the region between adjacent signal lines SL (regions not overlapping the multiple signal lines SL).

[0059] In the third modified example, the first shield portion 26Ca of the shield layer 26C also reduces the parasitic capacitance between adjacent signal lines SL. Furthermore, in the third modified example, the shield layer 26C is provided continuously below the signal lines SL across the signal lines SL, thereby effectively blocking noise that enters the signal lines SL from the substrate 21 side (below). The shield layer 26C is provided in a layer different from the signal lines SL and the lower electrodes 23 of the photodiodes PD, thereby improving the degree of freedom in arranging the shield layer 26C compared to the first embodiment and the modified examples described above.

[0060] (Fourth Modification) 9 is a cross-sectional view schematically showing the signal line and the shielding layer of a detection device according to a fourth modification. Note that a plan view of a detection device 1D according to the fourth modification is similar to FIG. 1, and therefore will not be repeated.

[0061] 9, in a detecting device 1D according to the fourth modification, a shield layer 26D is provided in a layer between the substrate 21 and the signal lines SL, and is disposed between adjacent signal lines SL in a plan view. In other words, unlike the third modification described above, a first shield portion 26Da of the shield layer 26D is provided in a layer below the multiple signal lines SL, not in an area overlapping the multiple signal lines SL, but in an area between adjacent signal lines SL (an area not overlapping the multiple signal lines SL). In the example shown in FIG. 9, the signal line SL-1, shield layer 26D-1, signal line SL-2, shield layer 26D-2, signal line SL-3, shield layer 26D-3, signal line SL-4, ... are alternately disposed in the first direction Dx.

[0062] In the fourth modification, the area of ​​the shield layer 26D below the signal line SL is smaller than in the third modification, which reduces the capacitance formed between the signal line SL and the shield layer 26D. Therefore, even when the shield layer 26D is provided, the time constant of the signal line SL is reduced, and it is possible to prevent an increase in the time required to read out the detection signal Vdet.

[0063] The first embodiment and the modifications described above can be combined as appropriate. That is, the number of shield layers 26, 26A, 26B, 26C, and 26D is not limited to one layer, and two or more layers may be provided. For example, the shield layer 26 of the first embodiment may be combined with the shield layer 26A of the first modification. Or, the shield layer 26 of the first embodiment may be combined with the shield layer 26B of the second modification. However, various combinations of the shield layers 26, 26A, 26B, 26C, and 26D may be provided.

[0064] Furthermore, the first shield portion 26a provided between the plurality of signal lines SL in plan view and the second shield portion 26b provided between the plurality of lower electrodes 23 are connected to form a continuous shield layer 26. However, without being limited to this, the first shield portion 26a and the second shield portion 26b may be provided spaced apart from each other and formed as separate shield layers.

[0065] 10 is a side view showing an example of using the detection device according to the first embodiment to measure biological information. In the first embodiment and each of the modifications described above, a configuration in which multiple photodiodes PD are arranged in the second direction Dy has been shown. As shown in FIG. 10, this detection device 1 can be used to observe the vein pattern of a wrist Wr, which is a detection object 100.

[0066] The substrate 21 of the detection device 1 is formed of a deformable, flexible material and is provided in a ring shape surrounding the wrist Wr. The light sources 91A and 92A are arranged in an arc shape along the ring-shaped substrate 21. Light L emitted from the light sources 91A and 92A is reflected by the blood vessels (veins) of the detection subject 100 and enters the multiple photodiodes PD of the sensor unit 10. The detection device 1 is not limited to the wrist Wr, and may be formed in a ring shape surrounding a finger. Alternatively, the detection device 1 can be used in, for example, a smart watch or a wearable device. The arrangement of the light sources 91A and 92A shown in FIG. 10 is merely an example and can be changed as appropriate depending on the device in which the detection device 1 is installed.

[0067] (Second embodiment) Fig. 11 is a plan view showing a detection device according to the second embodiment. As shown in Fig. 11, in a detection device 1E according to the second embodiment, a plurality of photodiodes PD are arranged in a matrix in a detection area AA of a substrate 21. A plurality of lower electrodes 23 are provided for each of the plurality of photodiodes PD and are arranged in a matrix in the detection area AA. In other words, the plurality of photodiodes PD (the plurality of lower electrodes 23) are arranged side by side in the first direction Dx and the second direction Dy. An upper electrode 24 (not shown in Fig. 11) is provided across the plurality of photodiodes PD and is provided continuously in the detection area AA.

[0068] The multiple signal lines SL are electrically connected to the respective lower electrodes 23 of the multiple photodiodes PD, extend across the regions overlapping with the lower electrodes 23, and are electrically connected to the detection circuit 48. For example, signal lines SL-1, SL-2, ..., SL-5 are connected to the respective lower electrodes 23-1, 23-2, ..., 23-5 of the multiple photodiodes PD arranged in the second direction Dy. In a plan view, the signal lines SL-1, SL-2, ..., SL-5 are arranged in the first direction Dx.

[0069] The signal line SL-1 connected to the lower electrode 23-1 extends in the second direction Dy, overlapping with the lower electrodes 23-2, 23-3, 23-4, and 23-5. The signal line SL-2 connected to the lower electrode 23-2 extends in the second direction Dy, overlapping with the lower electrodes 23-3, 23-4, and 23-5. The signal line SL-3 connected to the lower electrode 23-3 extends in the second direction Dy, overlapping with the lower electrodes 23-4 and 23-5. The signal line SL-4 connected to the lower electrode 23-4 extends in the second direction Dy, overlapping with the lower electrode 23-5. A plurality of photodiodes PD and a plurality of signal lines SL arranged in the second direction Dy with a similar arrangement relationship are arranged in the first direction Dx.

[0070] The shield layer 26E is provided so as to cover most of the detection area AA, and is provided continuously across the signal lines SL and the photodiodes PD in a plan view. That is, in the second embodiment, at least a portion of the shield layer 26E is disposed between the signal lines SL in a plan view.

[0071] Fig. 12 is a cross-sectional view taken along line XII-XII' in Fig. 11. As shown in Fig. 12, a plurality of signal lines SL, an insulating film 29, a shield layer 26E, an insulating film 27, and a plurality of photodiodes PD are stacked in this order on a substrate 21 in the third direction Dz. The stacked structure of the photodiodes PD is the same as that of the first embodiment described above, and a detailed description thereof will be omitted.

[0072] The shield layer 26E is formed in a layer between the plurality of signal lines SL and the plurality of lower electrodes 23 of the photodiodes PD. Openings OP are provided in the regions of the shield layer 26E that overlap with the lower electrodes 23. The lower electrodes 23 of the photodiodes PD are electrically connected to the signal lines SL through the openings OP provided in the shield layer 26E.

[0073] More specifically, a connection electrode CN1 is provided in the same layer as the shield layer 26E in a region overlapping with the opening OP. The connection electrode CN1 is provided separated from the shield layer 26E via a slit. The lower electrode 23 of the photodiode PD is electrically connected to the connection electrode CN1 via a contact hole CH1 provided in the insulating film 27. The connection electrode CN1 is electrically connected to the signal line SL-5 via a contact hole CH2 provided in the insulating film 29.

[0074] The shield layer 26E is provided in a layer above the signal lines SL, and is provided continuously over the region overlapping the signal lines SL and the region between adjacent signal lines SL (region not overlapping the signal lines SL). Furthermore, the shield layer 26E is provided between the lower electrode 23 and the signal lines SL not connected to the lower electrode 23 (signal lines SL-1 to SL-4 in FIG. 12).

[0075] With this configuration, the shield layer 26E suppresses the parasitic capacitance between adjacent signal lines SL. Therefore, even if a potential difference occurs between adjacent signal lines SL, fluctuations in the potential of the signal lines SL are suppressed. Furthermore, the shield layer 26E suppresses the parasitic capacitance between the signal lines SL and the lower electrodes 23. Therefore, even if a potential difference occurs between the lower electrodes 23 and signal lines SL that are not connected to the lower electrodes 23, fluctuations in the potential of the signal lines SL are suppressed.

[0076] (Third embodiment) Fig. 13 is a plan view showing a detection device according to embodiment 3. As shown in Fig. 13, the detection device 1F according to embodiment 3 further includes a plurality of drive transistors Tr, a plurality of gate lines GL, a gate line drive circuit 15, a signal line selection circuit 16, and a shield layer 26F.

[0077] The multiple photodiodes PD and lower electrodes 23 are arranged in a matrix in the detection area AA. Multiple drive transistors Tr are provided corresponding to the multiple photodiodes PD, respectively. The multiple gate lines GL each extend in a first direction Dx and are arranged in a second direction Dy. The multiple signal lines SL each extend in the second direction Dy and are arranged in the first direction Dx. The lower electrodes 23 of the photodiodes PD are arranged in an area surrounded by the multiple gate lines GL and the multiple signal lines SL. The detailed configurations of the shield layer 26F, the lower electrodes 23, and the signal lines SL will be described later with reference to FIG. 15.

[0078] The gate line driving circuit 15 and the signal line selection circuit 16 are provided in the peripheral area GA. The multiple photodiodes PD perform detection in accordance with gate driving signals supplied from the gate line driving circuit 15. The multiple photodiodes PD also output electrical signals corresponding to the light irradiated thereon as detection signals Vdet to the signal line selection circuit 16. As a result, the detection device 1 detects information about the object to be detected based on the detection signals Vdet from the multiple photodiodes PD.

[0079] More specifically, the gate line drive circuit 15 sequentially or simultaneously selects a plurality of gate lines GL and supplies a gate drive signal to the selected gate lines GL, which turns on the drive transistors Tr connected to the gate lines GL (to a conductive state), and the lower electrodes 23 of the plurality of photodiodes PD connected to the gate lines GL are electrically connected to the signal lines SL via the drive transistors Tr.

[0080] The signal line selection circuit 16 is a switch circuit that sequentially or simultaneously selects multiple signal lines SL. The signal line selection circuit 16 is, for example, a multiplexer. The signal line selection circuit 16 connects the selected signal line SL to the detection circuit 48 based on a selection signal ASW supplied from the control circuit 122 (see FIG. 1). For example, the signal line selection circuit 16 has multiple output transistors TrS, a selection signal line Lsel connected to the gates of the multiple output transistors TrS, and an output signal line Lout.

[0081] Based on the selection signal ASW supplied via the selection signal line Lsel, the output transistors TrS are sequentially turned on, and the selected signal line SL is electrically connected via the output signal line Lout to the detection circuit 48. As a result, the signal line selection circuit 16 is electrically connected to the photodiode PD corresponding to the selected signal line SL, and outputs the detection signal Vdet of the photodiode PD to the detection circuit 48.

[0082] Fig. 14 is a circuit diagram showing a detection device according to the third embodiment. Fig. 14 also shows the circuit configuration of a detection circuit 48. As shown in Fig. 14, the partial detection area PAA includes a photodiode PD, a capacitive element Ca, and a drive transistor Tr. The capacitive element Ca is a capacitance (sensor capacitance) formed in the photodiode PD, and is equivalently connected in parallel with the photodiode PD.

[0083] 14 shows two gate lines GL(m) and GL(m+1) aligned in the second direction Dy among the multiple gate lines GL. Also shown are two signal lines SL(n) and SL(n+1) aligned in the first direction Dx among the multiple signal lines SL. The partial detection area PAA is an area surrounded by the gate lines GL and the signal lines SL.

[0084] The drive transistors Tr are provided corresponding to the respective photodiodes PD. The drive transistors Tr are configured by thin film transistors, and in this example, are configured by n-channel MOS (Metal Oxide Semiconductor) TFTs (Thin Film Transistors).

[0085] The gates of the drive transistors Tr belonging to the partial detection areas PAA aligned in the first direction Dx are connected to the gate line GL. One of the source and drain of the drive transistors Tr belonging to the partial detection areas PAA aligned in the second direction Dy is connected to the signal line SL. The other of the source and drain of the drive transistor Tr is connected to the anode of the photodiode PD and the capacitance element Ca.

[0086] A sensor power supply signal VDDSNS is supplied to the cathode of the photodiode PD from a power supply circuit 123 (see FIG. 1). In addition, a sensor reference voltage COM, which serves as the initial potential of the signal line SL and the capacitance element Ca, is supplied to the signal line SL and the capacitance element Ca from the power supply circuit 123 via a reset transistor TrR.

[0087] When light is irradiated onto the partial detection area PAA during the exposure period, a current corresponding to the amount of light flows through the photodiode PD, causing charge to accumulate in the capacitance element Ca. When the drive transistor Tr is turned on during the readout period, a current corresponding to the charge accumulated in the capacitance element Ca flows through the signal line SL. The signal line SL is connected to the detection circuit 48 via the output transistor TrS of the signal line selection circuit 16. This allows the detection device 1 to detect a signal corresponding to the amount of light irradiated onto the photodiode PD for each partial detection area PAA.

[0088] During the readout period, the switch SSW of the detection circuit 48 is turned on, and the detection circuit 48 is connected to the signal line SL. The detection signal amplifier circuit 42 of the detection circuit 48 converts fluctuations in current supplied from the signal line SL into fluctuations in voltage and amplifies the voltage. A reference potential (Vref) having a fixed potential is input to the non-inverting input terminal (+) of the detection signal amplifier circuit 42, and the signal line SL is connected to the inverting input terminal (-). In this embodiment, a signal equal to the sensor reference voltage COM is input as the reference potential (Vref) voltage. The control circuit 122 (see FIG. 1) calculates the difference between the detection signal Vdet when light is irradiated and the detection signal Vdet when light is not irradiated as the sensor output voltage Vo. The detection signal amplifier circuit 42 also has a capacitance element Cb and a reset switch RSW. During the reset period, the reset switch RSW is turned on, and the charge of the capacitance element Cb is reset.

[0089] Fig. 15 is an enlarged plan view showing the multiple photodiodes and shield layers of Fig. 13. As shown in Fig. 15, the shield layer 26F is disposed between the signal line SL and the lower electrode 23 in a plan view. More specifically, the shield layer 26F has a first shield portion 26Fa extending in the first direction Dx, a second shield portion 26Fb (see Fig. 13) connecting the multiple first shield portions 26Fa, and a third shield portion 26Fc and a fourth shield portion 26Fd extending in the second direction Dy and intersecting the first shield portion 26Fa. In this embodiment, the respective portions constituting the shield layer 26F are formed in the same layer as the gate line GL.

[0090] The first shield portion 26Fa is provided so as to overlap the photodiodes PD (lower electrodes 23) arranged in the first direction Dx, and intersects with the signal lines SL. The first shield portions 26Fa are provided for each of the photodiodes PD arranged in the second direction Dy.

[0091] The second shield portion 26Fb (see FIG. 13) extends in the second direction Dy in the peripheral area GA and connects the right ends of the multiple first shield portions 26Fa, thereby electrically connecting the various portions of the shield layer 26F and supplying a common reference voltage VCOM.

[0092] The third shield part 26Fc is connected to the first shield part 26Fa and is disposed between the right side of the lower electrode 23 and the signal line SL in a plan view. The third shield part 26Fc extends along the right side of the lower electrode 23 and the signal line SL.

[0093] The fourth shield part 26Fd is connected to the first shield part 26Fa and is disposed between the left edge of the lower electrode 23 and the signal line SL in a plan view. The fourth shield part 26Fd extends along the left edge of the lower electrode 23 and the signal line SL. In other words, the lower electrode 23 is disposed between the third shield part 26Fc and the fourth shield part 26Fd in the first direction Dx. Alternatively, the signal line SL is disposed between the third shield part 26Fc and the fourth shield part 26Fd in the first direction Dx. The first shield part 26Fa is disposed so as to overlap the center of the lower electrode 23 in the second direction Dy. However, this is not limited thereto, and the first shield part 26Fa can be disposed at any position in a region that does not overlap with the gate line GL and the drive transistor Tr.

[0094] The drive transistor Tr has a semiconductor layer 61, a source electrode 62, a drain electrode 63, and a gate electrode 64. The semiconductor layer 61 extends along the gate line GL and intersects with the gate electrode 64 in a plan view. The gate electrode 64 is connected to the gate line GL and extends in a direction perpendicular to the gate line GL. One end of the semiconductor layer 61 is connected to the source electrode 62 via a contact hole CH4. The lower electrode 23 is electrically connected to the source electrode 62 of the drive transistor Tr via a contact hole (not shown). This electrically connects the drive transistor Tr to the photodiode PD. The other end of the semiconductor layer 61 is connected to the drain electrode 63 via a contact hole CH3. The drain electrode 63 is connected to a signal line SL.

[0095] The shield layer 26F is provided at a position that does not overlap with the drive transistor Tr. The first shield portion 26Fa is provided at a position that does not overlap with the semiconductor layer 61 and the gate electrode 64. The third shield portion 26Fc is arranged at a distance from the drain electrode 63 in the second direction Dy. The fourth shield portion 26Fd is provided between gate lines GL adjacent to each other in the second direction Dy and arranged at a distance from each of the gate lines GL.

[0096] Fig. 16 is a cross-sectional view taken along line XVI-XVI' in Fig. 15. As shown in Fig. 16, the shield layer 26F is provided in a layer between the substrate 21 and the lower electrode 23 of the photodiode PD in the third direction Dz. The shield layer 26F is also provided in a layer between the substrate 21 and the signal line SL in the third direction Dz.

[0097] Specifically, the shield layer 26F is provided on the substrate 21. The insulating film 29 is provided on the substrate 21, covering the shield layer 26F. The signal line SL is provided on the insulating film 29. The insulating film 27 is provided on the insulating film 29, covering the signal line SL. The lower electrode 23 of the photodiode PD is provided on the insulating film 27. The layered structure of the photodiode PD is the same as that of the first embodiment described above, and therefore a repeated description will be omitted.

[0098] With this configuration, the third shield portion 26Fc and the fourth shield portion 26Fd of the shield layer 26F suppress the parasitic capacitance between the signal line SL and the lower electrode 23. Therefore, in a configuration in which the signal line SL is provided between the lower electrodes 23 of a plurality of photodiodes PD and a plurality of photodiodes PD are arranged along one signal line SL, even if a potential difference occurs between the signal line SL and the lower electrode 23, fluctuations in the potential of the signal line SL are suppressed.

[0099] (Fifth Modification) 17 is an enlarged plan view showing a plurality of photodiodes and a shield layer of a detection device according to a fifth modified example. Note that a cross-sectional view of the detection device 1G according to the fifth modified example is similar to that of FIG. 16, and therefore will not be repeated.

[0100] 17, in a detection device 1G according to the fifth modification, a shield layer 26G is provided in the same layer as the gate lines GL and is connected to the gate lines GL. More specifically, FIG. 17 shows an enlarged view of a plurality of photodiodes PD-1 belonging to the first row and a plurality of photodiodes PD-2 belonging to the second row. The photodiode PD-1 is the photodiode PD located furthest in the second direction Dy in the detection area AA and farthest from the detection circuit 48 and the signal line selection circuit 16 (FIG. 13).

[0101] The gate line GL-1 is provided between the photodiodes PD-1 in the first row and the photodiodes PD-2 in the second row, and extends in the first direction Dx. The gate line GL-1 is connected to the drive transistors Tr of the photodiodes PD-1. The gate line GL-2 is provided between the photodiodes PD-2 in the second row and the photodiodes PD-3 (not shown in FIG. 17) in the third row, and extends in the first direction Dx. The gate line GL-2 is connected to the drive transistors Tr of the photodiodes PD-2.

[0102] Furthermore, a dummy wiring GLd that is not connected to the drive transistor Tr and does not function as a gate electrode 64 is provided on the side of the photodiodes PD-1 opposite to the gate line GL-1 (above the photodiode PD-1 in FIG. 17). The photodiodes PD-1 in the first row are arranged between the dummy wiring GLd and the gate line GL-1 in the second direction Dy in a plan view. The dummy wiring GLd is provided in the same layer as the gate line GL and extends in the first direction Dx.

[0103] In the photodiodes PD-2 in the second row, the first shield portion 26Ga of the shield layer 26G is connected to the gate line GL-1 and extends in the second direction Dy in plan view, and is disposed between the left side of the lower electrode 23-2 and the signal line SL. The second shield portion 26Gb of the shield layer 26G is connected to the gate line GL-1 and extends in the second direction Dy in plan view, and is disposed between the right side of the lower electrode 23-2 and the signal line SL. Similarly, a shield layer 26G connected to the gate line GL-(m-1) corresponding to the (m-1)th row is disposed between the lower electrode 23 of the photodiode PD-m in the m-th row and the signal line SL.

[0104] In the photodiodes PD-1 in the first row, the first shield portion 26Ga of the shield layer 26G is connected to the dummy wiring GLd, extends in the second direction Dy in plan view, and is disposed between the left side of the lower electrode 23-1 and the signal line SL. The second shield portion 26Gb of the shield layer 26G is connected to the dummy wiring GLd, extends in the second direction Dy in plan view, and is disposed between the right side of the lower electrode 23-1 and the signal line SL.

[0105] As described above, the shield layer 26G provided for the photodiode PD-m in the mth row is connected to another gate line GL-(m-1) adjacent to the gate line GL-m in the mth row. A gate drive signal is supplied to the gate line GL-m selected by the gate line drive circuit 15, and the reference voltage VCOM is supplied to the unselected gate lines GL (e.g., gate line GL-(m-1)). As a result, the reference voltage VCOM is supplied to the shield layer 26G provided for the photodiode PD-m in the mth row via the unselected gate line GL-(m-1).

[0106] Furthermore, in the multiple photodiodes PD-1 belonging to the first row, the shield layer 26G is connected to a dummy wiring GLd that is different from the gate line GL-1 connected to the drive transistor Tr of the photodiode PD-1. A reference voltage VCOM is supplied to the dummy wiring GLd. As a result, the reference voltage VCOM is supplied to the shield layer 26G provided in the photodiode PD-1 in the first row via the dummy wiring GLd. Note that the voltage supplied to the dummy wiring GLd is not limited to the reference voltage VCOM, and may be another reference voltage, such as an H (high) level voltage or an L (low) level voltage of the gate drive signal.

[0107] With this configuration, the shield layer 26G also suppresses parasitic capacitance between the signal line SL and the lower electrode 23 in the fifth modification. Furthermore, in the detection device 1G according to the fifth modification, the unselected gate lines GL and the dummy wiring GLd also serve as power supply wiring to the shield layer 26G. Therefore, in the fifth modification, the number of wirings can be reduced compared to the third embodiment, thereby improving the aperture ratio of the photodiodes PD. Furthermore, the unselected gate lines GL also serve as the shield layer 26G between the photodiodes PD adjacent in the second direction Dy. Furthermore, the dummy wiring GLd also serves as the shield layer 26G on the peripheral region GA side of the photodiode PD-1.

[0108] (Sixth Modification) 18 is an enlarged plan view showing multiple photodiodes and a shield layer of a detection device according to Modification 6. As shown in Fig. 18, a detection device 1H according to Modification 6 has a power supply wiring PL extending in the first direction Dx and a shield layer 26H extending in the second direction Dy and overlapping with a signal line SL.

[0109] The power supply lines PL are provided along the gate lines GL in the same layer as the gate lines GL and supply a reference voltage VCOM to the shield layer 26H. The power supply lines PL are provided for each of the gate lines GL arranged in the second direction Dy. That is, the power supply lines PL are provided for each of the photodiodes PD arranged in the second direction Dy.

[0110] The shield layer 26H is electrically connected to the power supply line PL via a contact hole CH5. A plurality of shield layers 26H are connected to one power supply line PL extending in the first direction Dx, and each shield layer 26H is provided for each of the plurality of photodiodes PD (lower electrodes 23). The shield layer 26H has a width greater than that of the signal line SL, and is provided between the lower electrodes 23 of adjacent photodiodes PD. In other words, the shield layer 26H includes, in a plan view, a portion overlapping the signal line SL and a portion not overlapping the signal line SL but disposed between the signal line SL and the lower electrode 23.

[0111] 19 is a cross-sectional view taken along line XIX-XIX' in FIG. 18. As shown in FIG. 19, the power supply wiring PL is provided between the substrate 21 and the shield layer 26H and lower electrode 23 in the third direction Dz. The shield layer 26H is provided in the same layer as the lower electrode 23, and is disposed between adjacent lower electrodes 23 in the first direction Dx. The shield layer 26H is formed of the same material as the lower electrode 23, such as a translucent conductive material such as ITO. The power supply wiring PL is formed of the same metal material as the gate line GL.

[0112] Specifically, the power supply wiring PL is provided on the substrate 21. An insulating film 29 is provided on the substrate 21, covering the power supply wiring PL. The signal line SL is provided on the insulating film 29. The connection electrode CN2 is provided on the insulating film 29 in the same layer as the signal line SL, and is arranged adjacent to the signal line SL in a region overlapping with the shield layer 26H. An insulating film 27 is provided on the insulating film 29, covering the signal line SL and the connection electrode CN2. The lower electrode 23 of the photodiode PD and the shield layer 26H are provided on the insulating film 27.

[0113] The shield layer 26H is electrically connected to the connection electrode CN2 through a contact hole CH5 provided in the insulating film 27. The connection electrode CN2 is electrically connected to the power supply wiring PL through a contact hole CH6 provided in the insulating film 29. In this way, the power supply wiring PL is electrically connected to the shield layer 26H through the contact holes CH5 and CH6 provided in the insulating films 27 and 29 that cover the power supply wiring PL. The layered structure of the photodiode PD is the same as that of the first embodiment described above, and therefore a repeated description will be omitted.

[0114] With this configuration, also in the sixth modified example, the shield layer 26H reduces the parasitic capacitance between the signal line SL and the lower electrode 23. Moreover, since the shield layer 26H is provided in the same layer as the lower electrode 23, the parasitic capacitance between the lower electrodes 23 adjacent to each other in the first direction Dx is also reduced.

[0115] (Seventh Modification) FIG. 20 is a plan view showing a detection device according to a seventh modification. As shown in FIG. 20, in a detection device 1I according to the seventh modification, a shield layer 26I is provided in a grid pattern, overlapping with each of a plurality of signal lines SL and a plurality of gate lines GL. More specifically, the shield layer 26I includes a plurality of first shield portions 26Ia extending in a first direction Dx and a plurality of second shield portions 26Ib extending in a second direction Dy and intersecting with the first shield portions 26Ia. The first shield portions 26Ia are arranged in the second direction Dy and overlap with the gate lines GL, respectively. The second shield portions 26Ib are arranged in the first direction Dx and overlap with the signal lines SL, respectively. The lower electrode 23 is disposed in a region surrounded by the first shield portions 26Ia and the second shield portions 26Ib in a plan view.

[0116] The power supply wiring PL is provided in the peripheral area GA and extends in the second direction Dy. The shield layer 26I is provided from the detection area AA to the peripheral area GA and is electrically connected to the power supply wiring PL through a plurality of contact holes CH7 in the peripheral area GA. The plurality of contact holes CH7 are arranged in the second direction Dy, thereby ensuring connection between the power supply wiring PL and the shield layer 26I.

[0117] 21 is a cross-sectional view taken along line XXI-XXI' in FIG. 20. As shown in FIG. 21, the shield layer 26I is provided on the insulating film 27 in the same layer as the lower electrode 23. The second shield portion 26Ib of the shield layer 26I is disposed between the lower electrodes 23 adjacent to each other in the first direction Dx. The second shield portion 26Ib has a width greater than that of the signal line SL and overlaps the signal line SL. That is, the second shield portion 26Ib includes, in a plan view, a portion that overlaps with the signal line SL and a portion that does not overlap with the signal line SL and is disposed between the signal line SL and the lower electrode 23.

[0118] Although not shown in the figures, the first shield portion 26Ia of the shield layer 26I also has a layered structure similar to that of the second shield portion 26Ib. The first shield portion 26Ia of the shield layer 26I is disposed between adjacent bottom electrodes 23 in the second direction Dy. The first shield portion 26Ia has a width greater than that of the gate line GL and overlaps the gate line GL. That is, the first shield portion 26Ia includes, in a plan view, a portion that overlaps with the gate line GL and a portion that does not overlap with the gate line GL and is disposed between the gate line GL and the bottom electrode 23.

[0119] Since the shield layer 26I is provided to cover most of the area of ​​the detection area AA that does not overlap with the lower electrode 23, the seventh modification can effectively suppress the parasitic capacitance between the signal line SL and the lower electrode 23.

[0120] The third embodiment and the fifth to seventh modifications described above can be combined as appropriate. That is, the number of shield layers 26F, 26G, 26H, and 26I is not limited to one layer, and two or more layers may be provided. For example, the shield layer 26F of the third embodiment may be combined with the shield layer 26H of the sixth modification. However, various combinations of the shield layers 26F, 26G, 26H, and 26I may be provided.

[0121] In the first to third embodiments and each of the modifications described above, the lower electrode 23 is the anode electrode of the photodiode PD, and the upper electrode 24 is the cathode electrode of the photodiode PD. However, without being limited to this, the lower electrode 23 may be the cathode electrode of the photodiode PD, and the upper electrode 24 may be the anode electrode of the photodiode PD. In this case, the photodiode PD is configured such that the lower buffer layer 32 includes an electron transport layer, and the upper buffer layer 33 includes a hole transport layer.

[0122] Furthermore, although the outer shape of each of the lower electrodes 23 is rectangular, the shape is not limited to this and may be other shapes such as polygonal or circular.

[0123] Although preferred embodiments of the present invention have been described above, the present invention is not limited to such embodiments. The contents disclosed in the embodiments are merely examples, and various modifications are possible without departing from the spirit of the present invention. Appropriate modifications made without departing from the spirit of the present invention naturally fall within the technical scope of the present invention. At least one of various omissions, substitutions, and modifications of components can be made without departing from the spirit of each of the above-described embodiments and modifications. [Explanation of symbols]

[0124] 1, 1A, 1B, 1C, 1D, 1E, 1F, 1G, 1H, 1I Detector 21 PCB 23 Lower electrode 24 Upper electrode 26, 26A, 26B, 26C, 26D, 26E, 26F, 26G, 26H, 26I Shielding layer 26a, 26Aa, 26Ba, 26Ca, 26Da, 26Fa, 26Ia First shield part 26b, 26Ab, 26Fb, 26Ib Second shield part 26Fc 3rd Shield Section 26Fd 4th shield part 27, 29 Insulating film 28 Sealing film 31 Active layer 32 Lower buffer layer 33 Upper buffer layer 48 Detection circuit OP opening PD photodiode AA detection area GA peripheral area SL signal line GL gate line

Claims

1. a plurality of photodiodes arranged in a matrix; a plurality of transistors provided corresponding to the plurality of photodiodes, respectively; a plurality of scanning lines each extending in a first direction and arranged in a second direction intersecting the first direction; a plurality of signal lines extending in the second direction and arranged in the first direction; a plurality of shielding layers; each of the plurality of signal lines is connected to a corresponding one of the plurality of transistors; each of the plurality of scanning lines is connected to a gate of a corresponding one of the plurality of transistors; each of the plurality of photodiodes is disposed in an area surrounded by the plurality of signal lines and the plurality of scanning lines; At least a portion of each of the plurality of shield layers is disposed in a region surrounded by the plurality of signal lines and the plurality of scanning lines, and does not overlap with the plurality of scanning lines and the plurality of signal lines. Detection device.

2. At least a portion of each of the plurality of shield layers is provided in an area that does not overlap with the lower electrode of the photodiode. The detection device according to claim 1 .

3. Each of the plurality of shield layers includes a first portion extending in the first direction and a second portion extending in the second direction and intersecting the first portion. The detection device according to claim 2 .

4. The second portion of the shield layer extending in the second direction is provided in a region that does not overlap with the lower electrode of the photodiode. The detection device according to claim 3 .

5. The first portion of the shield layer extending in the first direction is provided in a region overlapping with a lower electrode of the photodiode. The detection device according to claim 3 .

6. The shield layer is provided in the same layer as the scanning line. The detection device according to claim 2 .

7. The shield layer is connected to the scanning line and extends in the second direction in a region where it does not overlap with the lower electrode of the photodiode and the signal line. The detection device according to claim 6.

8. In each of the plurality of shield layers, the shield layer is disposed across a region overlapping the plurality of signal lines and a region not overlapping the plurality of signal lines, and the area of ​​the portion of the shield layer not overlapping the plurality of signal lines is larger than the area of ​​the portion overlapping the signal lines. The detection device according to claim 2 .

9. each of the plurality of photodiodes is formed by stacking a lower electrode, a lower buffer layer, an active layer, an upper buffer layer, and an upper electrode in this order; The lower electrodes are electrically connected to a plurality of signal lines, and are connected to one of the source and drain of a corresponding one of the plurality of transistors. The detection device according to any one of claims 1 to 8.

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