Organic semiconductor device

Abstract

Provided is an organic semiconductor device in which deterioration resulting from moisture or the like can be suppressed. An organic semiconductor device (100) includes a first substrate (1) and a second substrate (2) that face each other and are arranged with a gap therebetween, and a sealing material (3) that is disposed between the first substrate and the second substrate and is provided so as to surround a space (20) defined between the first substrate and the second substrate. At least one first element (10-14) configured to include an organic semiconductor film (14) is provided to one surface side of the first substrate within the space. At least one second element (15-17) is provided to one surface side of the second substrate within the space.

Description

Organic Semiconductor Devices

[0001] The present disclosure relates to organic semiconductor devices.

[0002] Japanese Patent Laid-Open Publication No. 2023-030471 (Patent Document 1) describes a detection device having a substrate, a plurality of photodiodes provided on the substrate, a plurality of transistors provided corresponding to each of the plurality of photodiodes, a plurality of gate lines extending in a first direction, a plurality of signal lines extending in a second direction intersecting the first direction, a plurality of lower electrodes provided between the transistors and the photodiodes in a direction perpendicular to the substrate and corresponding to each of the plurality of photodiodes, an upper electrode provided across the plurality of photodiodes, and a reflective layer provided between the substrate and the photodiodes in a direction perpendicular to the substrate.

[0003] The above-mentioned detection device has a structure in which the photodiode and transistor are mounted on the same substrate, and therefore requires surface treatment such as a passivation film covering the substrate in order to be commercialized. However, if the photodiode or transistor is made of organic material, for example, these are prone to deterioration due to moisture and oxygen, and it is thought that the above-mentioned passivation film will have difficulty in preventing the intrusion of moisture and oxygen from the outside.

[0004] Japanese Patent Application Laid-Open No. 2023-030471

[0005] An object of a specific embodiment of the present disclosure is to provide an organic semiconductor device that can suppress deterioration due to moisture or the like.

[0006] An organic semiconductor device according to one aspect of the present disclosure includes: a first substrate and a second substrate arranged with one surface facing each other and spaced apart; and a sealing material arranged between the first substrate and the second substrate and surrounding a space defined between the first substrate and the second substrate; wherein at least one first element including an organic semiconductor film is provided within the space on one surface side of the first substrate; and at least one second element is provided within the space on one surface side of the second substrate.

[0007] According to the above configuration, it is possible to provide an organic semiconductor device that can suppress deterioration due to moisture and the like.

[0008] FIG. 1 is a schematic cross-sectional view showing the configuration of an organic semiconductor device according to a first embodiment. FIG. 2 is a schematic cross-sectional view showing the configuration of an organic semiconductor device according to a second embodiment. FIG. 3 is a schematic cross-sectional view showing the configuration of an organic semiconductor device according to a third embodiment. FIGS. 4A to 4D are schematic cross-sectional views for explaining a method for manufacturing an organic semiconductor device 100a. FIGS. 5A and 5B are schematic plan views for explaining a method for manufacturing an organic semiconductor device 100a. FIGS. 6A and 6B are schematic plan views for explaining a method for manufacturing an organic semiconductor device 100a. FIGS. 7A and 7B are diagrams showing the configuration of an organic semiconductor device according to an example and an example circuit configuration, respectively.

[0009] 1 is a schematic cross-sectional view showing the configuration of an organic semiconductor device according to a first embodiment. The organic semiconductor device 100 of the first embodiment includes a thin-film transistor (first element) and a photodiode (second element) for detecting light, with the photodiode and thin-film transistor each being made of an organic material. The thin-film transistor includes a gate electrode 10, an insulating film 11, source / drain electrodes 12 and 13, and an organic semiconductor film 14 (shown by the dotted oval in the figure). The photodiode includes a transparent electrode 15, an active layer 16, and an electrode 17.

[0010] The first substrate 1 is, for example, a glass substrate or a resin substrate. The first substrate 1 may be, for example, a film-like substrate. The first substrate 1 may be a transparent substrate or a non-transparent substrate. The first substrate 1 has the above-mentioned thin film transistors provided on one surface thereof (the surface facing the second substrate 2). For this reason, the first substrate 1 used should have heat resistance sufficient to withstand at least the temperatures encountered during the manufacturing process of the thin film transistors.

[0011] The second substrate 2 is, for example, a film-like resin substrate. The second substrate 2 used in this embodiment is thinner than the first substrate 1. The second substrate 2 has the above-described photodiode provided on one surface (the surface facing the first substrate 1). Therefore, the second substrate 2 is heat-resistant to a degree that can withstand at least the temperatures during the manufacturing process of the photodiode. Furthermore, in this embodiment, light is incident on the photodiode through the second substrate 2, so the second substrate 2 is made of a material that has high transmittance at least for the wavelength of light to be detected. By forming the first substrate 1 and the second substrate 2 in the form of thin films, a flexible organic semiconductor device can be provided.

[0012] The sealing material 3 is provided between the surfaces of the first substrate 1 and the second substrate 2 so as to surround the photodiodes and thin-film transistors. The sealing material 3 contains spacers for maintaining a constant distance (e.g., several μm) between the surfaces of the first substrate 1 and the second substrate 2. The first substrate 1, the second substrate 2, and the sealing material 3 seal the space 20 between the first substrate 1 and the second substrate 1, i.e., the space 20 including the photodiodes and thin-film transistors, from the outside. The sealing material 3 can be, for example, a sealing material made of a photocurable or thermosetting epoxy resin similar to that used in liquid crystal elements.

[0013] The gate electrode 10 is an electrode that functions as the gate of the thin-film transistor, and is provided on one surface of the first substrate 1. The length and width of the gate electrode 10 can be set appropriately depending on the performance required of the thin-film transistor. The gate electrode 10 can be obtained by patterning a transparent conductive film such as an ITO (indium tin oxide) film, or a metal film such as gold, into a predetermined shape. Although not shown, wiring is connected to the gate electrode 10 as appropriate.

[0014] The insulating film 11 is provided on one surface of the first substrate 1 so as to cover the gate electrode 10. This insulating film 11 is an insulating film that functions as a gate insulating film of a thin film transistor, and may be an insulating film formed using, for example, an organic material, or may be an insulating film formed using a material such as SiN or SiO ２The insulating film 11 may be formed using an inorganic material such as a silicon dioxide film or the like. The relative dielectric constant, film thickness, etc. of the insulating film 11 can be set appropriately depending on the performance required for the thin film transistor. If the insulating film 11 is formed using an organic material, it can be formed, for example, by applying the organic material to one surface of the first substrate 1 and drying it. If the insulating film 11 is formed using an inorganic material, it can be formed using a film formation method such as a sputtering method or a CVD method.

[0015] The source / drain electrodes 12, 13 are provided on one surface of the insulating film 11 (the surface facing the second substrate 2), with each electrode partially overlapping the gate electrode 10 in a planar view. A gap is provided between the source / drain electrodes 12 and 13. This gap is positioned so as to overlap the gate electrode 10 in a planar view. The source / drain electrodes 12, 13 are electrodes that function as the source / drain of the thin-film transistor. The source / drain electrodes 12, 13 can be obtained by patterning a transparent conductive film such as an ITO (indium tin oxide) film or a metal film such as gold into a predetermined shape. Although not shown, wiring is connected to the source / drain electrodes 12, 13 as appropriate.

[0016] The organic semiconductor film 14 is provided at a position overlapping the gate electrode 10 in a plan view and in contact with each of the source / drain electrodes 12, 13. The organic semiconductor film 14 can be formed, for example, by applying an organic semiconductor material using a coating method such as an inkjet method. The film thickness, mobility, etc. of the organic semiconductor film 14 can be appropriately set depending on the performance required as a thin film transistor. Furthermore, as shown in FIG. 2 described below, a protective film 19 covering the organic semiconductor film 14 may be provided.

[0017] The transparent electrode 15 is provided on one surface of the second substrate 2. The transparent electrode 15 can be obtained by patterning a transparent conductive film such as an ITO (indium tin oxide) film into a predetermined shape. Although not shown, wiring is connected to the transparent electrode 15 as appropriate.

[0018] The active layer 16 is provided between the transparent electrode 15 and the electrode 17. This active layer 16 is a layer for generating an electromotive force by light incident from the outside through the second substrate 2 and the transparent electrode 15. Although not described here, functional layers such as a carrier injection layer, a carrier blocking layer, and a transport layer may be provided as appropriate between the active layer 16 and the transparent electrode 15 and between the active layer 16 and the electrode 17, respectively.

[0019] The electrode 17 is provided at a position facing the transparent electrode 15 across the active layer 16. The electrode 17 can be obtained by patterning a metal film such as an aluminum film.

[0020] The conductive material 18 is provided between one surface of the first substrate 1 and one surface of the second substrate 2 so as to contact the source / drain electrodes 13 of the thin-film transistor and the electrode 17 of the photodiode, respectively. The conductive material 18 may be, for example, a material such as silver paste. Alternatively, the conductive material 18 may be, for example, a resin containing a gap material (microspheres) coated with gold, or an anisotropic conductive adhesive film. The presence of the conductive material 18 between the source / drain electrodes 13 and the electrode 17 electrically and physically connects the thin-film transistor provided on the first substrate 1 and the photodiode provided on the second substrate 2.

[0021] The organic semiconductor device 100 of the first embodiment has the above-described configuration, and its operation will now be described. Light incident from the outside is detected by a photodiode provided on the second substrate 2. At this time, applying a predetermined voltage to the gate electrode 10 of the thin-film transistor provided on the first substrate 1 causes conduction between the source / drain electrodes 12, 13, allowing a photocurrent from the photodiode to be output to the outside. Various information can be obtained by observing the output waveform of this photocurrent.

[0022] 1 shows one pair of thin film transistor and one photodiode for ease of explanation, but a plurality of thin film transistors and photodiodes may be provided between the first substrate 1 and the second substrate 2. In this case, for example, the thin film transistors and photodiodes may be arranged in a matrix in a planar view, thereby obtaining planar optical information (time change). In this case, the wiring for each thin film transistor and photodiode may be arranged appropriately. For example, it is preferable to arrange a plurality of gate wirings and a plurality of data wirings orthogonally, and arrange and connect each thin film transistor and photodiode corresponding to each intersection of the wirings to drive each thin film transistor (active matrix drive).

[0023] In the organic semiconductor device 100 of the first embodiment, the thin film transistor and the photodiode are arranged in positions where they overlap in a planar view, but they may be arranged in positions where they do not overlap in a planar view. However, in consideration of area efficiency when multiple photodiodes are arranged, the former arrangement (where the thin film transistor and the photodiode overlap in a planar view) is more preferable. The same applies to each embodiment described below.

[0024] Furthermore, although a bottom-gate thin film transistor is exemplified in the organic semiconductor device 100 of the first embodiment, a top-gate thin film transistor may also be used. In that case, wiring may be drawn out from the source / drain electrodes as appropriate, and the wiring may be configured to be in contact with the conductive material 33. This also applies to the other embodiments described below.

[0025] According to the first embodiment described above, a first substrate provided with a thin film transistor and a second substrate provided with a photodiode are disposed opposite each other at a fixed distance, and the space 20 containing the thin film transistor and the photodiode is sealed with the sealing material 3, thereby providing an organic semiconductor device capable of suppressing deterioration due to the intrusion of moisture and the like from outside. Furthermore, by sealing the space 20 containing the thin film transistor and the photodiode with the sealing material 3, the thin film transistor and the photodiode can be formed on the first substrate and the second substrate under their respective optimal conditions, compared to a structure in which a passivation film is formed on a stack of the thin film transistor and the photodiode, thereby providing an organic semiconductor device with excellent electrical and optical properties. Furthermore, by sealing the space 20 containing the thin film transistor and the photodiode with the sealing material 3, the organic semiconductor device is less susceptible to damage (damage due to solvents or high temperatures) during passivation film formation, compared to a structure in which a passivation film is formed on a stack of the thin film transistor and the photodiode, thereby providing a highly reliable organic semiconductor device. The organic semiconductor device 100 of the first embodiment can be used, for example, to monitor blood flow in the human body.

[0026] 2 is a schematic cross-sectional view showing the configuration of an organic semiconductor device according to a second embodiment. The organic semiconductor device 100a according to the second embodiment includes a photodiode and a thin-film transistor having the same configuration as the organic semiconductor device 100 according to the first embodiment, and further includes a pressure sensor (third element), in which the photodiode and the thin-film transistor are made of organic materials. Note that the same reference numerals are used for components common to the organic semiconductor device 100 according to the first embodiment, and detailed description thereof will be omitted.

[0027] 2 includes a plurality of thin film transistors and a plurality of photodiodes between a first substrate 1 and a second substrate 2. In the illustrated example, the organic semiconductor device 100a includes two thin film transistors and two photodiodes. Each thin film transistor and photodiode are paired, facing each other, and are electrically and physically connected to each other via a conductive material 18. In the illustrated example, a protective film 19 is provided to cover the organic semiconductor film 14 of each thin film transistor, but this may be omitted.

[0028] Furthermore, a pressure sensor is disposed between one pair of thin film transistors and photodiodes and another pair of thin film transistors and photodiodes between the first substrate 1 and the second substrate 2. The pressure sensor includes electrodes 31, 32 and a pressure-sensitive material 33 provided so as to be interposed between these electrodes 31, 32. A space 20 including these thin film transistors, photodiodes, and pressure sensor is sealed from the outside by a sealing material 3 provided between each surface of the first substrate 1 and the second substrate 2.

[0029] The electrode 31 is provided on one surface of the insulating film 11 on one side of the first substrate 1. This electrode 31 can be formed, for example, in the same process as the process for forming the source / drain electrodes 12, 13. The electrode 31 can be obtained, for example, by patterning a transparent conductive film such as an ITO (indium tin oxide) film or a metal film such as gold into a predetermined shape. Although not shown, wiring is connected to the electrode 31 as appropriate.

[0030] The electrode 32 is provided on one surface of the second substrate 2. This electrode 32 can be formed, for example, in the same process as the process for forming the transparent electrode 15. The electrode 32 can be obtained by patterning a transparent conductive film such as an ITO (indium tin oxide) film into a predetermined shape. Although not shown, wiring is connected to the electrode 32 as appropriate.

[0031] The pressure-sensitive material 33 is disposed between one surface of each of the first substrate 1 and the second substrate 2, in contact with the electrodes 31 and 32, and is electrically and physically connected to each of them. The pressure-sensitive material 33 may be any material that changes some physical value when the distance between the first substrate 1 and the second substrate 2 changes due to external pressure, and is preferably a material that exhibits a change in electrical resistance value. Specifically, for example, a pressure-sensitive conductive elastomer or polyvinylidene fluoride having a piezoelectric effect can be used as the pressure-sensitive material 33. The pressure-sensitive conductive elastomer is formed by uniformly dispersing conductive particles (e.g., carbon) in insulating silicone rubber.

[0032] Although one pressure sensor is shown in the illustrated example, multiple pressure sensors may be provided. In this case, the pressure sensors may be arranged in a matrix similar to the photodiodes, each connected to a thin-film transistor, and operated by active matrix driving. Alternatively, multiple pressure sensors may be interconnected and passively driven without using switching elements such as thin-film transistors. In this case, the wiring connected to the electrodes 31 of each pressure sensor may be formed, for example, below the insulating film 11 (between the insulating film 11 and the first substrate 1), and the electrodes 31 and the wiring may be electrically and physically connected via contact holes provided in the insulating film 11.

[0033] According to the second embodiment described above, an organic semiconductor device can be obtained that can suppress deterioration due to the intrusion of moisture and the like from the outside, by arranging a first substrate provided with a thin film transistor and a second substrate provided with a photodiode opposite each other at a fixed distance and sealing a space 20 containing the thin film transistor, the photodiode, and the pressure sensor with the sealing material 3. The organic semiconductor device 100a of the second embodiment can be used, for example, to monitor pulse rates in the human body, detect respiratory activity, and measure blood pressure.

[0034] 3 is a schematic cross-sectional view showing the configuration of an organic semiconductor device according to a third embodiment. The organic semiconductor device 100b according to the third embodiment includes a photodiode and a thin-film transistor having the same configuration as the organic semiconductor device 100 according to the first embodiment, and further includes a light-emitting element (third element), in which the active layer of the photodiode and the active layer of the thin-film transistor are each made of an organic material. Note that the same reference numerals are used for components common to the organic semiconductor device 100 according to the first embodiment, and detailed description thereof will be omitted.

[0035] 3 includes a plurality of thin film transistors and a plurality of photodiodes between a first substrate 1 and a second substrate 2. In the illustrated example, the organic semiconductor device 100a includes two thin film transistors and two photodiodes. Each thin film transistor and photodiode are paired, facing each other, and are electrically and physically connected via a conductive material 18. Note that the protective film 19 covering the organic semiconductor film 14 of each thin film transistor may be omitted.

[0036] Furthermore, a light source is disposed between one pair of thin film transistors and photodiodes and another pair of thin film transistors and photodiodes between the first substrate 1 and the second substrate 2. The light source is configured to include an LED chip (light-emitting element) 40, a photospacer 41, and an electrode 42. A space 20 including these thin film transistors, photodiodes, and light source is sealed from the outside by a sealing material 3 provided between each surface of the first substrate 1 and the second substrate 2. Note that, although one light source (light-emitting element) is shown in the illustrated example, multiple light sources (light-emitting elements) may be provided.

[0037] The LED chip 40 is a semiconductor light-emitting element that emits light of a predetermined wavelength. The light emitted from the LED chip 40 is emitted to the outside through the second substrate 2. In one example of use, the light emitted to the outside from the LED chip 40 is reflected by an object (e.g., the skin of a subject), and the reflected light is detected by a photodiode.

[0038] The photospacer 41 is provided between one surface of the first substrate 1 and one surface of the second substrate 2 so as to surround the LED chip 40. In the illustrated example, the photospacer 41 is formed to have a trapezoidal cross section. The photospacer 41 can be formed, for example, by patterning a polyimide film. The photospacer 41 is intended to prevent light emitted from the LED chip 40 from directly entering the photodiode.

[0039] It is preferable that a metal reflective film made of silver, aluminum, or the like is provided on the inner surface of the photospacer 41, i.e., the surface that defines the space in which the LED chip 40 is present. Also, a layer with a light-blocking function, such as a black filter layer, may be formed instead of the photospacer 41. From the viewpoint of effective use of the light emitted from the LED chip 40, it is preferable to use a photospacer 41 having a metal reflective film on its inner surface.

[0040] The electrode 42 is provided on one surface of the insulating film 11 on one side of the first substrate 1. This electrode 42 is for supplying driving power to the LED chip 40 and is electrically and physically connected to the LED chip 40. This electrode 42 can be formed, for example, in the same manufacturing process as the source / drain electrodes 12, 13. The electrode 42 can be obtained, for example, by patterning a transparent conductive film such as an ITO (indium tin oxide) film or a metal film such as gold into a predetermined shape. Although not shown, wiring is connected to the electrode 42 as appropriate.

[0041] According to the third embodiment described above, a first substrate provided with a thin-film transistor and a second substrate provided with a photodiode are disposed opposite each other at a fixed distance, and a space 20 including the thin-film transistor, the photodiode, and the light source (light-emitting element) is sealed with the sealing material 3, thereby providing an organic semiconductor device capable of suppressing deterioration due to the intrusion of moisture and the like from the outside. The organic semiconductor device 100b of the third embodiment can be used, for example, for monitoring blood flow in the human body, a pulse sensor, or a pulse oximeter (monitoring blood oxygen concentration). Since light used for monitoring is emitted from the light source and the reflected light is detected by the photodiode, high functionality can be achieved.

[0042] Fourth Embodiment As the fourth embodiment, an example of a method for manufacturing the organic semiconductor device 100a of the second embodiment will be described. The organic semiconductor device 100 of the first embodiment has the same configuration as the organic semiconductor device 100a of the second embodiment except that it does not have a pressure sensor, and therefore the organic semiconductor device 100 of the first embodiment can be manufactured using the same manufacturing method as described below. Furthermore, the organic semiconductor device 100b of the third embodiment has the same configuration as the organic semiconductor device 100a of the second embodiment except that it has a light source instead of a pressure sensor, and therefore the organic semiconductor device 100b of the third embodiment can be manufactured using the same manufacturing method as described below.

[0043] FIGS. 4A to 4D are schematic cross-sectional views illustrating a manufacturing method of the organic semiconductor device 100a. FIGS. 5A, 5B, 6A, and 6B are schematic plan views illustrating a manufacturing method of the organic semiconductor device 100a. FIGS. 4A and 5A, 4B and 5B, 4C and 6A, and 4D and 6B show cross-sectional and plan views, respectively, of the same process. The cross sections shown in FIGS. 4A to 4D are cross sections taken along line a-a in FIGS. 5A, 5B, 6A, and 6B.

[0044] 4A and 5A, a process for forming a thin film transistor on the first substrate 1 will be described. First, a gate electrode 10 is formed on one surface of the first substrate 1. For example, the above-described transparent conductive film or metal film is formed on one surface of the first substrate 1, and then patterned by photolithography to obtain the gate electrode 10. The thickness of the gate electrode 10 can be, for example, about 40 nm.

[0045] Next, an insulating film 11 is formed on one surface of the first substrate 1 so as to cover the gate electrode 10. For example, the insulating film 11 can be formed by applying an organic material that will become the insulating film to one surface of the first substrate 1. As described above, the insulating film 11 may also be formed using an inorganic material.

[0046] Next, the source / drain electrodes 12, 13 and the electrode 31 are formed on one surface of the insulating film 11. At this time, wiring connected to each of the source / drain electrodes 12, 13 and wiring connected to the electrode 31 are also formed as needed. For example, a transparent conductive film or a metal film is formed on one surface of the insulating film 11, and the transparent conductive film or the like is patterned by photolithography to form the source / drain electrodes 12, 13 and the electrode 31. The film thickness of the source / drain electrodes 12, 13 and the electrode 31 can be, for example, about 40 nm.

[0047] When forming the organic semiconductor device 100b of the third embodiment, an electrode 42 is formed in place of the electrode 31 in this process, an LED chip 40 is placed on the electrode 42, and a photospacer 41 is formed.

[0048] Next, an organic semiconductor film 14 is formed at a position that contacts each of the source / drain electrodes 12, 13 and overlaps the gate electrode 10 in a planar view. For example, the organic semiconductor film 14 can be obtained by dropping an organic semiconductor material by a method such as an inkjet method onto a predetermined position that overlaps the gate electrode 10 in a planar view, and then drying it. The channel length and channel width of the organic semiconductor film 14 can be set to, for example, 10 μm and 500 μm, respectively. Furthermore, a protective film 19 is formed to cover the organic semiconductor film 14 as needed. This protective film 19 can be formed, for example, by applying an organic material that will serve as an insulating film onto the organic semiconductor film 14 and then drying it.

[0049] 4B and 5B, a process for forming a photodiode on the second substrate 2 will be described. Here, it is assumed that a film-like substrate is used as the second substrate 2. First, the second substrate 2 is placed on one surface of the support substrate 100. The support substrate 100 is used to support the second substrate 2 during the manufacture of the photodiode on the second substrate 2, and is configured to be peelable from the second substrate 2 later. The support substrate 100 can be, for example, a glass substrate.

[0050] The transparent electrode 15 and the electrode 32 are formed on one surface of the second substrate 2 supported by the support substrate 100. At this time, wiring connected to the transparent electrode 15 and wiring connected to the electrode 32 are also formed as needed. For example, the transparent conductive film as described above is formed on one surface of the second substrate 2 and then patterned by photolithography to obtain the transparent electrode 15 and the electrode 32. The thickness of the transparent electrode 15 and the electrode 32 can be, for example, about 40 nm.

[0051] Next, the active layer 16 is formed on one surface of the transparent electrode 15. For example, the active layer 16 can be obtained by dropping an organic semiconductor material by a method such as an inkjet method onto a predetermined position that overlaps the transparent electrode 15 in a planar view, and then drying the drop. The film thickness of the active layer 16 can be, for example, several tens of nanometers. Note that functional layers such as a carrier injection layer, a carrier blocking layer, or a transport layer may be formed between the active layer 16 and the transparent electrode 15, and between the active layer 16 and the electrode 17, respectively.

[0052] Next, an electrode 17 is formed at a position facing the transparent electrode 15 with the active layer 16 interposed therebetween. For example, the electrode 17 can be obtained by patterning a metal film such as an aluminum film. As an example, it is preferable to form the electrode 17 by a mask vapor deposition method. At this time, wiring to be connected to the electrode 17 is also formed as needed.

[0053] With reference to FIGS. 4(C) and 6(A), the steps of forming the conductive material 18 and the pressure-sensitive material 33 at predetermined positions on the first substrate 1 and the step of forming the sealing material 3 will be described. First, the conductive material 18 is formed at predetermined positions in contact with the source / drain electrodes 13. For example, the conductive material 18 can be formed by applying silver paste in dots using a dispenser. The pressure-sensitive material 33 is also formed at predetermined positions in contact with the electrodes 31. For example, the pressure-sensitive material 33 can be formed by applying a pressure-sensitive material in dots using a dispenser. The conductive material may be a sealing material containing Au balls (particles coated with Au). A gap control material may also be added to the conductive material. The conductive material will spread in the planar direction during the process of pressing the substrates together, as described below, so the conductive material is formed taking this spread into consideration.

[0054] Next, the sealing material 3 is applied so as to surround the periphery of the region where each thin film transistor is formed. When a gap control material is added to the sealing material 3, it is desirable that the diameter of the gap control material be smaller than the diameter of the conductive particles added to the conductive material 33.

[0055] The conductive material 18 , the pressure-sensitive material 33 , and the sealing material 3 may each be formed on the second substrate 2 instead of the first substrate 1 .

[0056] 4(D) and 6(B), the process of bonding the first substrate 1 and the second substrate 2 will be described. The first substrate 1 and the second substrate 2 are aligned and superimposed so that the conductive material 18 and the pressure-sensitive material 33 on the first substrate 1 contact the electrodes 17 and the electrodes 32 on the second substrate 2, respectively. This superimposition is preferably performed in an atmosphere of an inert gas such as nitrogen, or in a vacuum.

[0057] The first substrate 1 and the second substrate 2 are overlapped and pressed together to harden the sealing material 3. The hardening method may involve heat treatment, light irradiation treatment, or a combination of both, depending on the resin used as the material for the sealing material 3. It is also preferable to spray a gap control material on one surface of the first substrate 1 or the second substrate 2 before overlapping the first substrate 1 and the second substrate 2. Thereafter, the support substrate 100 is peeled off from the second substrate 2.

[0058] The organic semiconductor device 100a of the second embodiment can be manufactured by the method described above. According to the manufacturing method of the fourth embodiment, the thin film transistor and the photodiode are formed on separate substrates, and then the two substrates are bonded together. This allows the thin film transistor and the photodiode to be formed under conditions optimized for each. For example, restrictions on temperature conditions and the like can be reduced.

[0059] 7(A) and 7(B) are diagrams showing examples of the configuration and circuit configuration of an organic semiconductor device according to an example. Both are examples relating to the thin film transistor and photodiode portions of the organic semiconductor device according to each of the above-described embodiments. The organic semiconductor device according to the example shown in each of FIGS. 7(A) and 7(B) is configured to include a thin film transistor 110 and a photodiode 120. The differences between the examples are in the circuit configuration, which will be explained below.

[0060] In each embodiment, the thin film transistor 110 is formed using a glass substrate as the first substrate 1. The gate electrode 10 is an aluminum electrode having a thickness of 50 nm formed by vacuum deposition. The insulating film 11 is an alumina film (Al 2 O 3 ) having a thickness of 20 nm formed by sputtering. ２ O ３The insulating film used is a laminate of a 60 nm thick PVCi film and a 30 nm thick gold electrode formed by vacuum deposition. The source / drain electrodes 12 and 13 are 30 nm thick gold electrodes. The organic semiconductor material constituting the organic semiconductor film 14 can be a low molecular weight organic semiconductor material, preferably a liquid crystalline low molecular weight organic semiconductor material. In particular, a liquid crystalline low molecular weight organic semiconductor material having BTBT (dialkylbenzothienobenzothiophene) or anthracene as an aromatic π-electron conjugated moiety is preferably used. The organic semiconductor film 14 in each example is made of the liquid crystalline low molecular weight organic semiconductor material Ph-BTBT-10 (2-Decyl-7-phenyl[1]benzothieno[3,2-b][1]benzothiophene). A liquid crystalline organic semiconductor is an organic semiconductor that exhibits a liquid crystal phase. The organic semiconductor has an aromatic π-electron conjugated moiety that serves as a charge transport moiety.

[0061] In each embodiment, the photodiode 120 is formed using a glass substrate as the second substrate 2. The transparent electrode 15 is an ITO electrode with a thickness of 40 nm, formed by sputtering. In each embodiment, a PEIE (ethoxylated polyethyleneimine) intermediate film is provided between the ITO electrode and the active layer. The active layer 16 is a layer with a microlayer separation structure (bulk heterojunction structure) formed by mixing a donor material and an acceptor material. A conjugated polymer or a low-molecular-weight organic semiconductor material can be used as the donor material. A low-molecular-weight semiconductor material can be used as the acceptor material. Specifically, the donor material is a liquid crystalline phthalocyanine derivative 8H. ２ Pc is used as the donor material. ２ Non-liquid crystal phthalocyanine derivatives such as Pc (1,4,8,11,15,18,22,25-octaalkoxy-phthalocyanine) can also be used. The fullerene derivative PC61BM (Phenyl-C61-butylic acid methyl ester) is used as the acceptor material. The electrodes 17 are made of MoO films with a thickness of 5 nm, each formed by vacuum deposition.３ An electrode made of a laminate of a thin film and a gold film with a thickness of 50 nm is used.

[0062] In the embodiment of Fig. 7(A), the source / drain electrodes 12, 13 of the thin film transistor that function as the source are connected to the photodiode electrode 17 via a conductive material (conductive resin material) such as silver paste. On the other hand, in the embodiment of Fig. 7(B), the drain electrodes 12, 13 of the thin film transistor that function as the drain are connected to the photodiode electrode 17 via a conductive material (conductive resin material) such as silver paste.

[0063] The thin film transistors of each example have a mobility of 2.0×10 -2 cm 2 The results showed excellent transistor characteristics, with a threshold voltage of 1.7V and a Vs of 1.7V. Furthermore, both the thin-film transistor and the photodiode were found to be less susceptible to degradation due to external moisture, and good operation was confirmed even after a long period of time. Furthermore, no degradation of the characteristics of either device was observed even after a 500-hour high-temperature, high-humidity test at 60°C and 90% RH.

[0064] The present disclosure is not limited to the above-described embodiments and can be implemented in various modifications within the scope of the gist of the present disclosure. For example, in the above-described embodiments and examples, examples of organic semiconductor devices have been shown that include thin-film transistors and photodiodes formed using organic materials, but organic semiconductor devices to which the present disclosure can be applied are not limited to these. The present disclosure can be applied to organic semiconductor devices that include various elements formed using organic semiconductors, and can be applied to, for example, semiconductor devices that include liquid crystal elements and organic EL elements using thin-film transistors made of organic materials, various sensors exemplified by photodiodes, dye-sensitized solar cells, and perovskite solar cells.

[0065] The present disclosure has the following features. (Supplementary Note 1) An organic semiconductor device including a first substrate and a second substrate arranged with one surface facing each other and a gap between them, and a sealing material arranged between the first substrate and the second substrate and surrounding a space defined between the first substrate and the second substrate, wherein at least one first element including an organic semiconductor film is provided within the space on one surface side of the first substrate, and at least one second element is provided within the space on one surface side of the second substrate. (Supplementary Note 2) The organic semiconductor device according to Supplementary Note 1, further including a conductive material provided within the space between the first substrate and the second substrate, wherein the first element and the second element are electrically connected to each other via the conductive material. (Supplementary Note 3) The organic semiconductor device according to Supplementary Note 1 or 2, wherein the first element is a thin-film transistor. (Supplementary Note 4) The organic semiconductor device according to any of Supplements 1 to 3, wherein the organic semiconductor film is formed using an organic semiconductor having liquid crystal properties. (Supplementary Note 5) The organic semiconductor device according to any one of Supplementary Notes 1 to 4, wherein the second element is a photodiode. (Supplementary Note 6) The organic semiconductor device according to Supplementary Note 5, wherein the photodiode has an active layer using an organic semiconductor. (Supplementary Note 7) The organic semiconductor device according to any one of Supplementary Notes 1 to 6, wherein the first element and the second element are arranged so as to at least partially overlap in a planar view. (Supplementary Note 8) The organic semiconductor device according to any one of Supplementary Notes 1 to 7, further comprising at least one third element provided in the space and arranged at a position not overlapping with the first element and the second element in a planar view. (Supplementary Note 9) The organic semiconductor device according to Supplementary Note 8, wherein the third element is a pressure sensor. (Supplementary Note 10) The organic semiconductor device according to Supplementary Note 8, wherein the third element is a light-emitting element.

[0066] 1: first substrate, 2: second substrate, 3: sealing material, 10: gate electrode, 11: insulating film, 12, 13: source / drain electrodes, 14: organic semiconductor film, 15: transparent electrode, 16: active layer, 17: electrode, 18: conductive material

Claims

1. An organic semiconductor device comprising: a first substrate and a second substrate arranged with one surface facing each other and spaced apart; and a sealant arranged between the first substrate and the second substrate and surrounding a space defined between the first substrate and the second substrate; wherein at least one first element including an organic semiconductor film is arranged within the space on one surface side of the first substrate, and at least one second element is arranged within the space on one surface side of the second substrate.

2. The organic semiconductor device according to claim 1, further comprising a conductive material provided in the space between the first substrate and the second substrate, the first element and the second element being electrically connected to each other via the conductive material.

3. The organic semiconductor device according to claim 1, wherein the first element is a thin film transistor.

4. The organic semiconductor device according to claim 1, wherein the organic semiconductor film is made of an organic semiconductor having liquid crystal properties.

5. The organic semiconductor device according to claim 1, wherein the second element is a photodiode.

6. The organic semiconductor device according to claim 5, wherein the photodiode has an active layer using an organic semiconductor.

7. The organic semiconductor device according to claim 1, wherein the first element and the second element are arranged so as to at least partially overlap each other in a plan view.

8. The organic semiconductor device according to claim 1, further comprising at least one third element provided within the space and arranged at a position not overlapping with the first element and the second element in a plan view.

9. The organic semiconductor device according to claim 8, wherein the third element is a pressure sensor.

10. The organic semiconductor device according to claim 8, wherein the third element is a light-emitting element.

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