Thin film device, thin film device module, seal material with electrode, and method of manufacturing thin film device

Abstract

To provide a thin film device capable of being made by thermal compression bonding at a low temperature.SOLUTION: A thin film device comprises a first electrode, an active layer, a second electrode, an adhesive layer, and a barrier layer. The active layer is sandwiched between the first electrode and the second electrode. The adhesive layer is provided between the second electrode and the barrier layer, and bonds the second electrode and the barrier layer together. The adhesive layer has a glass-transition temperature of 20°C or lower.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a thin film device, a thin film device module, a sealing material with electrodes, and a method for manufacturing a thin film device. [Background technology]

[0002] Thin-film solar cells are a typical example of thin-film devices. Thin-film solar cells are attracting attention because they have few restrictions on where they can be installed and are said to be relatively easy to enlarge.

[0003] A thin-film solar cell is obtained by sequentially stacking a first electrode, an active layer, and a second electrode. Each layer of a thin-film solar cell is formed by, for example, a dry process such as vacuum deposition, sputtering, ion plating, or chemical vapor deposition, or a wet process in which a dispersion is applied. For example, Patent Document 1 describes a method for producing a second electrode by a wet process.

[0004] The active layer is easily damaged by heat and solvents. For example, when an electrode is vapor-deposited on the active layer, the active layer is damaged by the heat during vapor deposition. Also, when an electrode is applied to the active layer using a wet process, the active layer is damaged by the solvent contained in the coating solution.

[0005] In order to avoid damage to the active layer, a method for manufacturing a thin-film solar cell using thermocompression bonding has been investigated. For example, Patent Document 2 proposes a method in which a first laminate having an active layer and a second laminate having a second electrode are separately produced and then thermocompression bonded together.

[0006] Furthermore, thin-film devices such as thin-film transistors and thin-film diodes have a similar structure to thin-film solar cells and have the same problems as thin-film solar cells. It is believed that the manufacturing method for thin-film solar cells can also be applied to the manufacturing of other thin-film devices. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Japanese Patent Application Laid-Open No. 2014-236064 [Patent Document 2] Japanese Patent Application Publication No. 2023-17360 Summary of the Invention [Problem to be solved by the invention]

[0008] The thin-film solar cell manufacturing method described in Patent Document 2 does not directly form an electrode on the active layer, so damage to the active layer is minimal. However, when using an active layer that is easily damaged, such as a perovskite solar cell, the thin-film solar cell may not exhibit ideal characteristics.

[0009] The present invention has been made in view of the above problems, and has as its object to provide a thin film device that can be fabricated by a low-temperature thermocompression bonding process in order to avoid damage to the active layer. [Means for solving the problem]

[0010] In order to solve the above problems, the present invention provides the following means.

[0011] A thin film device according to a first aspect comprises a first electrode, an active layer, a second electrode, an adhesive layer, and a barrier layer. The active layer is sandwiched between the first electrode and the second electrode. The adhesive layer is located between the second electrode and the barrier layer and bonds the second electrode and the barrier layer. The adhesive layer has a glass transition temperature of 20°C or lower. [Effects of the Invention]

[0012] The thin film device according to this embodiment can be fabricated by low-temperature thermocompression bonding, and has excellent output characteristics. [Brief explanation of the drawings]

[0013] [Figure 1]1 is a plan view of a thin-film solar cell module according to a first embodiment. [Figure 2] 1 is a cross-sectional view of a thin-film solar cell module according to a first embodiment. [Figure 3] FIG. 2 is a cross-sectional view illustrating a first step in the method for manufacturing a thin-film solar cell according to the first embodiment. [Figure 4] FIG. 4 is a cross-sectional view illustrating a second step in the method for manufacturing a thin-film solar cell according to the first embodiment. [Figure 5] FIG. 4 is a cross-sectional view illustrating a third step in the method for manufacturing a thin-film solar cell according to the first embodiment. [Figure 6] FIG. 4 is a cross-sectional view illustrating a fourth step in the method for manufacturing a thin-film solar cell according to the first embodiment. [Figure 7] FIG. 4 is a cross-sectional view illustrating a fifth step in the method for manufacturing a thin-film solar cell according to the first embodiment. [Figure 8] 1 is a cross-sectional view of a thin film transistor according to a first embodiment. [Figure 9] 1 shows the IV characteristics of thin-film solar cells of Example 1, Comparative Example 1, and Reference Example 1. [Figure 10] 1 shows the IV characteristics of the thin-film solar cells of Example 2 and Comparative Example 2. [Figure 11] 1 is an optical microscope photograph of a bonded electrode. [Figure 12] The resistance measurement results of Example 3 and Comparative Example 3 are shown. [Figure 13] 10 shows the change in JV characteristics during continuous operation of the thin-film solar cell module of Example 3. [Figure 14] 1 shows the characteristics of thin film transistors of Example 4 and Comparative Example 3. DETAILED DESCRIPTION OF THE INVENTION

[0014] The present embodiment will be described in detail below. The following description is an example of the present invention, and the present invention is not limited thereto, and can be implemented with appropriate modifications within the scope of the present invention.

[0015] First, let us define the directions. In a thin-film device module, one direction on the surface where the thin-film device extends is defined as the X direction, and the direction perpendicular to the X direction within the same surface is defined as the Y direction. The direction perpendicular to the X and Y directions is defined as the Z direction. The Z direction coincides with the stacking direction of each layer in the thin-film device.

[0016] FIG. 1 is a plan view of a thin-film solar cell module M according to a first embodiment. The thin-film solar cell module M is an example of a thin-film device module. A thin-film solar cell is an example of a thin-film device. Here, a thin-film device will be specifically described using a thin-film solar cell, which is an example of a thin-film device. The thin-film device is not limited to a thin-film solar cell, and may be a thin-film transistor, a thin-film diode, or a thin-film light-emitting element.

[0017] The thin-film solar cell module M includes, for example, a plurality of thin-film solar cells C, a first terminal T1, and a second terminal T2. Each of the plurality of thin-film solar cells C corresponds to a cell of the thin-film solar cell module M. The thin-film solar cells C are electrically connected in series. Power generated by each of the thin-film solar cells C is output to the outside via the first terminal T1 and the second terminal T2.

[0018] Fig. 2 is a cross-sectional view of a portion of a thin-film solar cell module M according to the first embodiment. Fig. 2 is an enlarged cross-sectional view of the vicinity of a first thin-film solar cell C1 and a second thin-film solar cell C2 among a plurality of thin-film solar cells C. The first thin-film solar cell C1 is adjacent to the second thin-film solar cell C2. The first thin-film solar cell C1 is an example of a first thin-film device, and the second thin-film solar cell C2 is an example of a second thin-film device.

[0019] The first thin-film solar cell C1 and the second thin-film solar cell C2 each have a substrate 8, a first electrode 1, an electron collection layer 4, a power generation layer 3, a hole collection layer 5, a second electrode 2, a first adhesive layer 6, a first barrier layer 7, a second adhesive layer 9, and a second barrier layer 10. The substrate 8, the first adhesive layer 6, the first barrier layer 7, the second adhesive layer 9, and the second barrier layer 10 extend across the first thin-film solar cell C1 and the second thin-film solar cell C2. That is, the first thin-film solar cell C1 and the second thin-film solar cell C2 share the substrate 8, the first adhesive layer 6, the first barrier layer 7, the second adhesive layer 9, and the second barrier layer 10.

[0020] The first thin-film solar cell C1 and the second thin-film solar cell C2 are separated by a slit SL1. The slit SL1 is filled with a material that constitutes the first adhesive layer 6. The second electrode 2 of the first thin-film solar cell C1 and the first electrode 1 of the second thin-film solar cell C2 are connected by a through electrode 11. The first thin-film solar cell C1 and the second thin-film solar cell C2 are electrically connected in series via the through electrode 11. The width of the through electrode 11 in the short direction when viewed in a plan view from the Z direction is, for example, 100 μm or less, and preferably 50 μm or less.

[0021] The substrate 8 is not particularly limited as long as it can support a structure. The substrate 8 preferably has excellent light transmittance. For example, the substrate 8 has a visible light transmittance of 90% or more. The substrate 8 is also preferably flexible. The substrate 8 is, for example, glass, a plastic film, or the like. Examples of resins that can be used to form the plastic film include polyethylene terephthalate and polyethylene naphthalate.

[0022] The first electrode 1 is, for example, a transparent electrode. The first electrode 1 is on a substrate 8. A known first electrode 1 can be used. The first electrode 1 is, for example, a conductive transparent oxide film, graphene, carbon nanotubes, or a conductive polymer film. Examples of conductive transparent oxides include indium tin oxide (ITO), indium zinc oxide (IZO), zinc oxide, tin oxide, and titanium oxide.

[0023] The electron collecting layer 4, the power generating layer 3, and the hole collecting layer 5 are collectively referred to as the active layer. The active layer is sandwiched between the first electrode 1 and the second electrode 2. The active layer may be, for example, a single or multiple semiconductor layers. The electron collecting layer 4 and the hole collecting layer 5 sandwich the power generating layer 3. The electron collecting layer 4 is, for example, located on the first electrode 1 side of the power generating layer 3. The hole collecting layer 5 is, for example, located on the second electrode 2 side of the power generating layer 3. The positional relationship between the electron collecting layer 4 and the hole collecting layer 5 may be reversed depending on the energy levels of the first electrode 1 and the second electrode 2. For example, when the second electrode 2 is made of gold, the relationship shown in FIG. 1 is satisfied. However, when the second electrode 2 is made of aluminum, the positional relationship between the electron collecting layer 4 and the hole collecting layer 5 is reversed. The electron collecting layer 4 is sometimes called an electron transport layer, and the hole collecting layer 5 is sometimes called a hole transport layer.

[0024] The electron-collecting layer 4 is a layer that collects electrons in order to efficiently transport the electrons generated in the power generation layer 3 toward the first electrode 1. The electron-collecting layer 4 is, for example, an n-type semiconductor. Any known material can be used for the electron-collecting layer 4. The electron-collecting layer 4 may be, for example, an inorganic material such as a metal oxide or a metal nitride, or may be an inorganic material such as PCBM (phenyl-C 61 -butyric acid methyl ester), fullerene C 60 The electron-collecting layer 4 may be made of, for example, cadmium sulfide, zinc selenide, zinc sulfide, cadmium telluride, or other organic materials. Examples of metal oxides include titanium oxide, zinc oxide, silicon oxide, tin oxide, tungsten oxide, tantalum oxide, barium titanate, barium zirconate, zirconium oxide, hafnium oxide, aluminum oxide, yttrium oxide, and zirconium silicate. Examples of metal nitrides include silicon nitride. Other examples of materials that can be used for the electron-collecting layer 4 include cadmium sulfide, zinc selenide, zinc sulfide, and cadmium telluride.

[0025] The power generation layer 3 is a layer that receives light and generates electricity. The power generation layer 3 contains a donor and an acceptor. The power generation layer 3 may be a layer in which the donor and acceptor are mixed (bulk heterostructure), or may be a layer in which a donor layer and an acceptor layer are stacked (stacked structure). The donor absorbs light and becomes excited. The excited exciton moves to the interface between the donor and acceptor. When the exciton transfers an electron to the acceptor, the donor generates a cation (hole), and the acceptor generates an anion. The cations and anions flow toward different electrodes, causing a current to flow in an external circuit.

[0026] The donor is, for example, a p-type organic semiconductor. Known donors can be used. Examples of donors include conjugated polymers, phthalocyanine derivatives, porphyrin derivatives, triarylamine derivatives, carbazole derivatives, and oligothiophene derivatives. For example, poly(3-hexylthiophene-2,5-diyl) (P3HT) is a conjugated polymer and can be used as the donor.

[0027] The acceptor is, for example, an n-type organic semiconductor. Known acceptors can be used, and may be non-fullerene compounds or fullerene compounds. Examples of fullerene compound acceptors include

[60] PCBM, bis-

[60] PCBM,

[70] PCBM, and bis-

[70] PCBM. Other examples of fullerene compound acceptors include fullerene derivatives (SIMEF) having a silylmethyl group. Examples of non-fullerene compound acceptors include TTBT compounds, ITIC compounds, IDT compounds, IDTT compounds, TTCTT compounds, and PPhTQ.

[0028] The power generation layer 3 may also be made of a material having a perovskite structure. A perovskite structure is a cubic crystal structure represented by the general formula ABX3. Different atoms or molecules are arranged at the vertices of the cube (A sites), the centers of each face of the cube (X sites), and the center of the cube (B site). Materials such as CH3NH3 and CH5N2 are used for the A sites. Materials such as Pb, Sn, and Ge are used for the B sites. Materials such as I, Cl, and Br are used for the X sites.

[0029] The hole-collecting layer 5 is a layer that collects holes in order to efficiently transport electrons generated in the power generation layer 3 toward the second electrode 2. A known hole-collecting layer can be used for the hole-collecting layer 5. For example, the hole-collecting layer 5 is PEDOT:PSS (a composite of poly(3,4-ethylenedioxythiophene) (PEDOT) and polystyrene sulfonic acid (PSS)).

[0030] The second electrode 2 is made of a conductive material. The second electrode 2 is on the active layer. The second electrode 2 is made of, for example, a metal such as gold, silver, or aluminum, or an organic conductive ink such as PEDOT:PSS. The portion of the second electrode 2 that overlaps with the through electrode 11 in a plan view from the Z direction may be recessed toward the first electrode 1 side.

[0031] The first adhesive layer 6 is between the second electrode 2 and the first barrier layer 7. The first adhesive layer 6 bonds the second electrode 2 and the first barrier layer 7 together.

[0032] The first adhesive layer 6 has a glass transition temperature of 20°C or lower. If the first adhesive layer 6 satisfies this condition, the first adhesive layer 6 becomes sufficiently soft even at low temperatures when the first barrier layer 7 and the second electrode 2 are thermocompression-bonded together, allowing the first barrier layer 7 and the second electrode 2 to be thermocompression-bonded together even at low temperatures. For example, the first barrier layer 7 and the second electrode 2 can be thermocompression-bonded together at 80°C.

[0033] Furthermore, the first adhesive layer 6 has a glass transition temperature of 20°C or less, and becomes sufficiently soft during thermocompression bonding. Because the first adhesive layer 6 is soft, a portion of the first adhesive layer 6 fills the slit SL1 during thermocompression bonding, preventing peeling of the thin-film solar cell C. A portion of the second electrode 2 that follows the deformation of the first adhesive layer 6 fills the slit and becomes the through electrode 11. The soft first adhesive layer 6 easily deforms during thermocompression bonding, and the second electrode 2, which changes shape in response to the deformation of the first adhesive layer 6, reliably enters the slit. As a result, the shape of the through electrode 11 is less likely to be distorted after attachment.

[0034] The thickness of the first adhesive layer 6 is, for example, 10 μm to 100 μm, and preferably 30 μm to 50 μm. When the first adhesive layer 6 is sufficiently thick, the filling of the first adhesive layer 6 or the second electrode 2 into the slits during thermocompression bonding is improved.

[0035] The first adhesive layer 6 is, for example, an acrylic adhesive, a urethane adhesive, or a nitrile rubber adhesive. The acrylic adhesive is an adhesive containing an acrylic polymer. The urethane adhesive is an adhesive containing polyurethane obtained by condensing compounds having an isocyanate group and a hydroxyl group. The nitrile rubber adhesive is an adhesive based on nitrile rubber.

[0036] The first barrier layer 7 prevents moisture and the like from entering the active layer and also prevents contamination of the active layer. The first barrier layer 7 is in contact with the first adhesive layer 6.

[0037] The first barrier layer 7 is made of SiO x The first barrier layer 7 is a barrier film in which a metal oxide such as SiOC or Al2O3 is laminated. The substrate constituting the first barrier layer 7 is, for example, a polyester film (e.g., PET), a polycarbonate film, a polyimide film, etc. Furthermore, to improve weather resistance, a functional film such as a fluorine film or an ultraviolet-blocking film may be further laminated.

[0038] The thickness of the first barrier layer 7 is, for example, 125 μm or less, and preferably 50 μm or less. This thickness is the thickness after thermocompression bonding. When the first barrier layer 7 has sufficient flexibility, the conformability of the second electrode 2 to the active layer is improved.

[0039] The second adhesive layer 9 is located between the substrate 8 and the second barrier layer 10. The second adhesive layer 9 bonds the substrate 8 and the second barrier layer 10 together. Because the second adhesive layer 9 contacts the flat substrate 8, it does not need to have the function required of the first adhesive layer 6. The second adhesive layer 9 can be made of, for example, the same material as the first adhesive layer 6. The second adhesive layer 9 may or may not contain, for example, the same material as the first adhesive layer 6. A known adhesive can be used for the second adhesive layer 9.

[0040] The second barrier layer 10 prevents moisture and other contaminants from entering the active layer and also prevents contamination of the active layer. The second barrier layer 10 is in contact with the second adhesive layer 9. Because the second barrier layer 10 is in contact with the flat second adhesive layer 9, it does not need to have some of the functions required of the first barrier layer 7. The second barrier layer 10 can be made of, for example, the same material as the first barrier layer 7. The second barrier layer 10 may or may not contain, for example, the same material as the first barrier layer 7.

[0041] Next, a method for manufacturing a thin-film solar cell according to this embodiment will be described. The method for manufacturing a thin-film solar cell includes steps 1, 2, 3, 4, and 5. Figures 3 to 7 are diagrams for explaining the method for manufacturing a thin-film solar cell according to this embodiment.

[0042] In the first step, a first film F1 is produced. Figure 3 is a cross-sectional view illustrating the first step. In the first step, a first adhesive layer 6 is applied to a first barrier layer 7 to produce the first film F1. A pre-produced film of the first film F1 may be purchased.

[0043] In the second step, a second film F2 is produced. FIG. 4 is a cross-sectional view illustrating the second step. In the second step, a second electrode 2 is formed on a separator 12 to form a second film F2. The second electrode 2 may be produced by mask deposition using vapor deposition, sputtering, or the like, or by pattern printing. For example, the second electrode 2 is produced by applying a silver paste diluted with 1,2-dimethoxyethane onto the separator 12 and baking it. The second electrode 2 is patterned, and slits SL2 are formed between adjacent second electrodes 2.

[0044] The separator 12 is a film that will be peeled off in a step described later, so there is no particular limitation on the material of the separator 12. The second step may be performed after or before the first step.

[0045] In the third step, a third film F3 is produced. FIG. 5 is a cross-sectional view illustrating the third step. In the third step, the first film F1 and the second film F2 are laminated together so that the first adhesive layer 6 and the second electrode 2 are in contact with each other, thereby producing the third film F3. The slits SL2 between adjacent second electrodes 2 are filled with the first adhesive layer 6. The third film F3 is an electrode-attached encapsulant comprising the second electrode 2, the first adhesive layer 6, and the first barrier layer 7. The third film F3 can be thermocompression bonded to the active layer after peeling off the separator 12.

[0046] It is also possible to form a third film F3 in which the first barrier layer 7, the first adhesive layer 6, and the second electrode 2 are laminated by forming the second electrode 2 on the first adhesive layer 6 of the first film F1. However, in this case, the first adhesive layer 6 is soft, so the patterning accuracy of the second electrode 2 is low. If the second electrode 2 is patterned on the separator 12 and then the second electrode 2 and the first adhesive layer 6 are bonded, a second electrode 2 with a precise shape can be produced. This is because the separator 12 is harder than the first adhesive layer 6, so the patterning accuracy of the second electrode 2 can be increased.

[0047] In the fourth step, a fourth film F4 is produced. FIG. 6 is a cross-sectional view illustrating the fourth step. In the fourth step, a first electrode 1, an electron-collecting layer 4, a power-generating layer 3, and a hole-collecting layer 5 are sequentially stacked on a substrate 8. These layers can be formed by, for example, vapor deposition, sputtering, or coating. After the first electrode 1, the electron-collecting layer 4, the power-generating layer 3, and the hole-collecting layer 5 are formed, slits SL3 and SL4 are formed in predetermined positions. The slit SL3 is the portion that will become the through electrode 11. The slit SL4 separates the first thin-film solar cell C1 from the second thin-film solar cell C2. The fourth step may be performed before or after steps 1 to 3.

[0048] In the fifth step, the separator 12 is peeled off from the third film F3, and the third film F3 and the fourth film F4 are thermocompression bonded together. FIG. 7 is a cross-sectional view illustrating the fifth step. When the separator 12 is peeled off from the third film F3, the second electrode 2 is adhered to the first adhesive layer 6. The second electrode 2 is adhered to the separator 12 side and is not peeled off. By thermocompression bonding the third film F3 and the fourth film F4 together, the second electrode 2 and the active layer are thermocompression bonded together.

[0049] When the third film F3 and the fourth film F4 are thermocompression bonded together, they are aligned so that the slits SL2 and SL4 coincide with each other. By aligning the slits SL2 and SL4, a portion of the first adhesive layer 6 also fills the slit SL4. The first adhesive layer 6 has a glass transition temperature of 20°C or less and becomes sufficiently soft during thermocompression bonding, allowing it to fully penetrate into the slit SL4. A portion of the second electrode 2 fills the slit SL3 during thermocompression bonding.

[0050] The thermocompression bonding temperature is, for example, preferably 80°C or higher and lower than 150°C, and more preferably 80°C or higher and 100°C or lower. By setting the thermocompression bonding temperature to 80°C or higher and lower than 150°C, damage to the active layer can be reduced. Furthermore, by setting the thermocompression bonding temperature to 80°C or higher and lower than 150°C, deterioration in performance of the thin-film solar cell C can be suppressed even when the active layer has a perovskite structure. Furthermore, by setting the thermocompression bonding temperature to 80°C or higher and 100°C or lower, it is possible to suppress the first adhesive layer 6 from becoming too soft during thermocompression bonding, which can cause the pattern of the second electrode 2 to become distorted.

[0051] The pressure for thermocompression is, for example, 80 g / cm 2 More than 650g / cm 2 The pressure for thermocompression is, for example, 80 g / cm 2 More than 325g / cm 2 The following is more preferable: If the pressure is too high, the performance of the thin-film solar cell C tends to decrease; if the pressure is too low, the conformability of the second electrode 2 to the active layer decreases.

[0052] The thermocompression bonding time is, for example, 1 minute or more. The thermocompression bonding time is preferably 3 minutes or more and 10 minutes or less, and more preferably 4 minutes or more and 6 minutes or less. If the thermocompression bonding time is short, the performance of the thin-film solar cell C tends to decrease, and if the thermocompression bonding time is long, the stability of the thin-film solar cell C tends to decrease.

[0053] By performing thermocompression bonding, the second electrode 2 is tightly attached to the surface of the active layer. Thereafter, a second adhesive layer 9 and a second barrier layer 10 are formed on the back surface of the substrate 8 to obtain a thin-film solar cell C. The second adhesive layer 9 and the second barrier layer 10 are not necessary.

[0054] In the thin-film solar cell C according to the first embodiment, the active layer and the second electrode 2 can be thermocompression bonded at low temperatures by using a predetermined first adhesive layer 6. When thermocompression bonding is used in the manufacturing process of the thin-film solar cell C, the second electrode 2 is not formed directly on the active layer, thereby reducing damage to the active layer. Furthermore, by performing thermocompression bonding at low temperatures, damage to the active layer can be further reduced. As a result, even when the power generation layer 3 has a perovskite structure, damage to the power generation layer 3 can be reduced, and performance degradation of the thin-film solar cell C can be suppressed.

[0055] Furthermore, by forming the second film F2 separately from the third film F3, damage caused by process errors can be reduced. If the second electrode 2 is formed directly on the active layer, an error in forming the second electrode 2 would require the active layer to be discarded as well. In contrast, if the second film F2 is formed separately from the third film F3, even if an error occurs in forming the second electrode, only the second film F2 needs to be discarded, preventing increases in process costs. Furthermore, by producing the second film F2 separately from the first film F1, the patterning accuracy of the second electrode 2 can be improved.

[0056] Although the preferred embodiments of the present invention have been described in detail above, the present invention is not limited to the specific embodiments, and various modifications and changes are possible within the scope of the gist of the present invention as set forth in the claims.

[0057] For example, thin-film solar cells can be replaced with thin-film transistors, thin-film diodes, and thin-film light-emitting devices. The layer structures of thin-film diodes and thin-film light-emitting devices are similar to those of thin-film solar cells. Known organic semiconductors can be used for the active layer of thin-film diodes.

[0058] 8 is a cross-sectional view of a thin film transistor 20 according to the first embodiment. The thin film transistor 20 includes a first electrode 21, a second electrode 22, a third electrode 23, an insulating layer 24, an active layer 25, a first adhesive layer 26, and a first barrier layer 27.

[0059] The first electrode 21 is a gate electrode. The first electrode 21 includes a known material such as Si. The second electrode 22 and the third electrode 23 are source and drain electrodes. The second electrode 22, the third electrode 23, and the first electrode 21 sandwich the active layer 25 in the stacking direction. There is no particular restriction on the materials of the second electrode 22 and the third electrode 23 as long as they are conductive. Portions of the second electrode 22 and the third electrode 23 protrude outward from the active layer 25 when viewed in the stacking direction. These protruding portions serve as contact portions between the second electrode 22 and the third electrode 23 and external terminals.

[0060] The insulating layer 24 is a gate insulator. The insulating layer 24 is, for example, silicon oxide. The active layer 25 is, for example, an organic semiconductor.

[0061] The first adhesive layer 26 is located between the first barrier layer 27 and the active layer 25. The first adhesive layer 26 corresponds to the first adhesive layer 6 in the thin-film solar cell. The first adhesive layer 26 contains the same properties and material as the first adhesive layer 6 in the thin-film solar cell. The first adhesive layer 26 is located between the second electrode 22 and the third electrode 23 in a plan view. The first barrier layer 27 corresponds to the first barrier layer 7 in the thin-film solar cell. The first barrier layer 27 contains the same properties and material as the first barrier layer in the thin-film solar cell.

[0062] The thin-film transistor 20 can be fabricated by thermocompression bonding an encapsulant with electrodes, which includes a second electrode 22, a third electrode 23, a first adhesive layer 26, and a first barrier layer 27, to the active layer 25 of a laminate which includes a first electrode 21, an insulating layer 24, and an active layer 25. The encapsulant with electrodes can be fabricated using the same procedure as for the third film shown in FIG. 5.

[0063] When the thin film transistor 20 is fabricated using this sealing material with electrodes, damage to the active layer 25 of the thin film transistor 20 can be suppressed, and the performance of the thin film transistor 20 can be improved. [Example]

[0064] Example 1 An encapsulant with an electrode was prepared as the third film F3. This encapsulant with an electrode had an adhesive layer corresponding to the first adhesive layer 6, VERREAL50M006-A corresponding to the first barrier layer 7, and a gold electrode corresponding to the second electrode 2. The glass transition temperature of the first adhesive layer 6 was 18°C.

[0065] In addition to the third film F3, a fourth film F4 was also produced. The fourth film F4 was produced by sequentially laminating an electron collection layer 4, a power generation layer 3, and a hole collection layer 5 on a substrate 8 on which a first electrode 1 had been formed. The substrate 8 was made of glass. The first electrode 1 was made of ITO. The electron collection layer 4 was made of zinc oxide. The power generation layer 3 used poly(3-hexylthiophene-2,5-diyl) (P3HT) as the donor and

[60] PCBM as the acceptor. The power generation layer 3 has a bulk heterostructure. The hole collection layer 5 was made of PEDOT:PSS.

[0066] Next, the separator 12 was peeled off from the third film F3, and the third film F3 and the fourth film F4 were thermocompression bonded together at 80°C for 5 minutes with a pressure of 0.1 N / cm. 2 The area of the light-receiving surface of thin-film solar cell C is 0.1 cm 2 It was decided.

[0067] The current-voltage curve (IV curve) of the fabricated thin-film solar cell C was measured using a 4262 multi-meter manufactured by ADC Corporation.

[0068] (Comparative Example 1) Comparative Example 1 differs from Example 1 in that CELAIR (registered trademark) F1550H (manufactured by Kureha Extron Co., Ltd.) was used as the first film F1 constituting the third film F3. The glass transition temperature of the material constituting the adhesive layer of CELAIR (registered trademark) F1550H (manufactured by Kureha Extron Co., Ltd.) is 38°C. In Comparative Example 1, the second film F2 was not produced, and a second electrode was formed directly on the adhesive layer of the first film F1. Then, a laminate consisting of the first barrier layer, the first adhesive layer, and the second electrode was thermocompression bonded to the fourth film F4. The temperature during thermocompression bonding was 150°C. The other layer configurations and conditions in Comparative Example 1 were the same as those in Example 1. The current-voltage curve (IV curve) of the thin-film solar cell of Comparative Example 1 was measured in the same manner as in Example 1.

[0069] (Reference example 1) In Reference Example 1, a second electrode was formed on the active material layer by vapor deposition. Specifically, the second electrode 2 was formed directly on the active layer of the fourth film F4. One surface of the second electrode 2 was then covered with CELAIR (registered trademark) F1550H (manufactured by Kureha Extron Co., Ltd.). The other layer configurations and conditions in Reference Example 1 were the same as those in Example 1. The current-voltage curve (IV curve) of the thin-film solar cell of Reference Example 1 was measured in the same manner as in Example 1.

[0070] Fig. 9 shows the measurement results of the IV characteristics of the thin-film solar cells of Example 1, Comparative Example 1, and Reference Example 1. As shown in Fig. 9, the IV characteristics of the thin-film solar cell of Example 1 were superior to the IV characteristics of the thin-film solar cell of Comparative Example 1. It is believed that the thermocompression bonding in Example 1 was performed at a lower temperature than in Comparative Example 1, which resulted in less damage to the active layer.

[0071] Example 2 Example 2 differs from Example 1 in that the power generation layer 3 constituting the active layer was changed to a material having a perovskite structure. The other conditions were the same as in Example 1. The power generation layer 3 in Example 2 was made of MAPBI3 (MA: methylammonium), and the current-voltage curve (IV curve) of the thin-film solar cell of Comparative Example 2 was measured in the same manner as in Example 1.

[0072] (Comparative Example 2) Comparative Example 2 differs from Example 2 in that CELAIR (registered trademark) F1550H (manufactured by Kureha Extron Co., Ltd.) was used as the first film F1 constituting the third film F3. In Comparative Example 2, the second film F2 was not produced, and a second electrode was formed directly on the adhesive layer of the first film F1. Then, a laminate consisting of the first barrier layer, the first adhesive layer, and the second electrode was thermocompression bonded to the fourth film F4. The temperature during thermocompression bonding was 150°C. The other layer configurations and conditions in Comparative Example 2 were the same as those in Example 2. The current-voltage curve (IV curve) of the thin-film solar cell of Comparative Example 2 was measured in the same manner as in Example 1.

[0073] Fig. 10 shows the measurement results of the IV characteristics of the thin-film solar cells of Example 2 and Comparative Example 2. As shown in Fig. 10, Comparative Example 2 did not provide an appropriate IV characteristic, whereas Example 2 provided an appropriate IV characteristic. As shown in Example 2, the method according to this embodiment makes it possible to obtain a perovskite solar cell that exhibits appropriate performance.

[0074] Example 3 In Example 3, a thin-film solar cell module was fabricated using the same procedure as in Example 1, with multiple thin-film solar cells arranged on the same plane, and the characteristics of the through-electrode were measured. Figure 11 is an optical microscope photograph of the through-electrode after thermocompression bonding. As shown in Figure 11, the boundary between the through-electrode and the other parts was confirmed as a straight line, and no distortion or the like of the through-electrode was confirmed.

[0075] FIG. 12 shows the resistance measurement results between the first and second electrodes in Example 3 and in Comparative Example 3 when no through-electrodes are provided. Because Comparative Example 3 does not have through-electrodes, the active layer is sandwiched between the first and second electrodes as a resistor. In contrast, in Example 3, the first and second electrodes are connected by through-electrodes, resulting in low resistance and a large current flow between the first and second electrodes. This confirms that the second electrode 2 is securely filled in the slit SL3 and the through-electrode is reliably formed, even when the third film F3 and the fourth film F4 are bonded together by thermocompression bonding. In Example 3, the depth of the slit SL3 was 300 nm, and a portion of the second electrode 2 penetrated and filled the 300-nm-deep slit SL3 during thermocompression bonding.

[0076] 13 shows the change in the JV characteristics during continuous operation of the thin-film solar cell module in Example 3. As shown in Fig. 13, the characteristics of the solar cell module did not change due to continuous operation, and no peeling or the like occurred in the thermocompression bonded portions.

[0077] Example 4 In Example 4, a thin-film transistor shown in FIG. 8 was fabricated. The first electrode 21 was made of Si, the insulating layer 24 was made of SiO2, and the active layer 25 was made of N,N'-dioctylnaphthalene-1,4,5,8-diimide. The thin-film transistor was fabricated by thermocompression bonding an encapsulant with electrodes, including a first adhesive layer 26, a first barrier layer 27, a second electrode 22, and a third electrode 23, to the active layer 25 of a laminate consisting of the first electrode 21, the insulating layer 24, and the active layer 25. The encapsulant with electrodes used was VERREAL50M006-A manufactured by Reiko Co., Ltd. This encapsulant with electrodes was the same as that used in Example 1.

[0078] (Comparative Example 3) Comparative Example 3 differs from Example 4 in that it does not have the first adhesive layer 26 and the first barrier layer 27. The thin film transistor of Comparative Example 3 was fabricated by vapor-depositing the second electrode 22 and the third electrode 23 on the active layer 25 of the laminate consisting of the first electrode 21, the insulating layer 24, and the active layer 25.

[0079] 14 shows the transfer characteristics under an atmospheric environment of the thin film transistors of Example 4 and Comparative Example 3. As shown in Fig. 14, the thin film transistor of Comparative Example 3 did not exhibit stable transistor characteristics, but the thin film transistor of Example 4 exhibited stable transistor characteristics. This is thought to be because thermocompression bonding did not cause significant damage to the active layer 25, and the first barrier layer 27 prevented moisture from penetrating into the active layer 25. [Explanation of symbols]

[0080] 1 1st electrode 2 2nd electrode 3 Power generation layer 4 Electron collection layer 5. Hole collection layer 6 First adhesive layer 7 First barrier layer 8 PCB 9 Second adhesive layer 10 Second barrier layer 11 Through electrode 12 Separator C Thin film solar cell C1 1st thin film solar cell C2 2nd thin film solar cell F1 Film 1 F2 2nd Film F3 Third Film F4 4th Film M Thin-film solar cell module SL1, SL2, SL3, SL4 slits T1 Terminal 1 T2 Terminal 2

Claims

1. a first electrode, an active layer, a second electrode, an adhesion layer, and a barrier layer; the active layer is sandwiched between the first electrode and the second electrode, the adhesive layer is between the second electrode and the barrier layer and adheres the second electrode and the barrier layer; A thin film device, wherein the adhesive layer has a glass transition temperature of 20°C or less.

2. The thin film device according to claim 1 , wherein the adhesive layer is an acrylic adhesive, a nitrile rubber adhesive, or a urethane adhesive.

3. 2. The thin film device according to claim 1, wherein the barrier layer is a PET film having a SiOC film formed on the surface thereof.

4. a plurality of thin film devices; A thin film device module, wherein each of the plurality of thin film devices is the thin film device according to claim 1 .

5. the adhesion layer and the barrier layer extend across the plurality of thin film devices; the plurality of thin film devices include a first thin film device and a second thin film device adjacent to the first thin film device; the second electrode of the first thin-film device and the first electrode of the second thin-film device are connected by a through electrode; The thin film device module according to claim 4 , wherein the width of the through electrode is 100 μm or less.

6. an electrode, an adhesive layer, and a barrier layer; the electrode is adhered to the barrier layer via the adhesive layer; The adhesive layer has a glass transition temperature of 20°C or less, An encapsulant with electrodes that can be thermocompressed onto the active layer.

7. Obtaining a first film having a barrier layer and an adhesive layer applied thereto; obtaining a second film in which a second electrode is formed on a separator; laminating the first film and the second film so that the adhesive layer and the second electrode are in contact with each other to produce a third film; peeling the separator from the third film and thermocompression bonding the second electrode to the active layer.

Images