JP2024092135A - Photoelectric conversion element, electronic apparatus, and method for manufacturing photoelectric conversion element - Google Patents

Abstract

To provide a photoelectric conversion element in which adjacent cells are joined in series and which has a high photoelectric conversion efficiency, and also to provide a method for manufacturing a photoelectric conversion element having a high conversion efficiency.SOLUTION: A photoelectric conversion element includes a transparent support substrate, a transparent first conductive layer laminated on the support substrate, a second conductive layer, and a photoelectric conversion layer which is sandwiched between the first conductive layer and the second conductive layer and which contains an organic material. A part of the first conductive layer has a thicker thickness than the photoelectric conversion layer. The first conductive layer has two first compartments that are adjacent via a substrate exposed area where a part of the support substrate is exposed from the first conductive layer, and the second conductive layer has two second compartments that are adjacent with a part of the substrate exposed area sandwiched therebetween. The photoelectric conversion layer has a photoelectric conversion layer penetration part penetrating in a thickness direction, in a photoelectric conversion layer connection overlapping both one of the two adjacent first compartments and the other of the two adjacent second compartments in plan view.SELECTED DRAWING: Figure 1

Description

The present invention relates to a photoelectric conversion element, an electronic device, and a method for manufacturing a photoelectric conversion element.

Photoelectric conversion elements have a photoelectric conversion function that converts sunlight and indoor light into electricity, and are being developed as a means of generating electricity using renewable energy. Organic photoelectric conversion elements are a type of photoelectric conversion element, and Patent Documents 1 and 2 disclose a configuration that includes a photoelectric conversion layer made of an organic thin film, and a first conductive layer and a second conductive layer that sandwich the photoelectric conversion layer. Patent Document 3 discloses a configuration that includes a photoelectric conversion layer made of an organometal halide perovskite, and a first conductive layer and a second conductive layer that sandwich the photoelectric conversion layer. The first conductive layer is, for example, a transparent conductive layer such as ITO (Indium Tin Oxide).

In organic photoelectric conversion elements, it is desirable to use an organic conductive film such as silver nanowires or PEDOT:PSS, which can be applied at room temperature and in an atmospheric environment by printing methods, rather than ITO, which is a transparent electrode with low environmental impact, as the first conductive layer using conventional sputtering deposition. However, when these applied first conductive layers are removed by laser after forming a photoelectric conversion layer on the first conductive layer to create a multi-junction that connects adjacent cells in series, the first conductive layer is removed at the same time as the photoelectric conversion layer containing the organic material, which poses the problem that the first conductive layer and the second conductive layer cannot make electrical contact.

Patent Document 1 also discloses a configuration including a photoelectric conversion layer made of an organic thin film, and a first conductive layer and a second conductive layer sandwiching the photoelectric conversion layer. The first conductive layer is a transparent conductive layer such as ITO. Figure 4 of the same document discloses an organic photoelectric conversion element. When the photoelectric conversion layer is formed on the first conductive layer and then removed using a laser, protrusions are generated on the processed end surface, which causes a problem that the connection resistance between the first conductive layer and the second conductive layer increases when multiple junctions are formed to connect adjacent cells in series.

JP 2017-168798 A JP 2011-100923 A JP 2022-54424 A

In view of the background of the conventional technology, the object of the present invention is to provide an organic photoelectric conversion element in which adjacent cells are connected in series, which has high photoelectric conversion efficiency, and to provide a method for manufacturing a photoelectric conversion element with high photoelectric conversion efficiency.

A photoelectric conversion element comprising a transparent support substrate, a transparent first conductive layer and a second conductive layer stacked on the support substrate, and a photoelectric conversion layer containing an organic material sandwiched between the first conductive layer and the second conductive layer, a portion of the first conductive layer being thicker than the photoelectric conversion layer, the first conductive layer having two first partitions adjacent to each other via a substrate exposed region where a portion of the support substrate is exposed from the first conductive layer, the second conductive layer having two second partitions adjacent to each other with a portion of the substrate exposed region sandwiched therebetween, and the photoelectric conversion layer having a photoelectric conversion layer penetration portion penetrating through the thickness direction at a photoelectric conversion layer connection portion that overlaps with both one of the two adjacent first partitions and the other of the two adjacent second partitions in a plan view.

The present invention allows adjacent cells to be connected in series with reduced connection resistance, thereby increasing the photoelectric conversion efficiency of the photoelectric conversion element.

1 is a plan view showing a main portion of a photoelectric conversion element according to a first embodiment of the present invention. 2 is a cross-sectional view taken along line II in FIG. 1. 2 is a cross-sectional view taken along line II-II in FIG. 1 is a bird's-eye view of the display side of a mobile phone equipped with a photoelectric conversion element according to a first embodiment of the present invention. 1 is a bird's-eye view of the rear side of a mobile phone equipped with a photoelectric conversion element according to a first embodiment of the present invention. 4 and 5. Reference numeral 7 denotes a first cover, 8 denotes a display, 9 denotes an electronic circuit board, 10 denotes a photoelectric conversion element, 11 denotes a battery, a second cover, 13 denotes an outer peripheral frame, 14 denotes a mobile phone, and H denotes the thickness of the mobile phone. 1 is an external view of a photoelectric conversion element incorporated in a mobile phone according to a first embodiment of the present invention. 1 is a block diagram showing a configuration of a mobile phone incorporating a photoelectric conversion element according to a first embodiment of the present invention. 2A to 2C are diagrams illustrating a method for manufacturing a photoelectric conversion element according to the first embodiment of the present invention. 5A to 5C are diagrams illustrating the manufacturing method (continuation) of the photoelectric conversion element based on the first embodiment of the present invention. 1A to 1C are diagrams illustrating a method for producing a photoelectric conversion element produced in an example. FIG. 13 is a diagram showing the manufacturing method (continuation) of the photoelectric conversion element produced in the example.

The preferred embodiment of the present invention will be described in detail below with reference to the drawings.

[First embodiment]
The reference numerals in the first embodiment and in Figures 1 to 9-2 are valid in these embodiments and figures and are independent of the reference numerals in other embodiments and figures. However, the specific configurations of the first embodiment and the specific configurations of the other embodiments can be appropriately combined with each other.

In the present invention, "transparent" is defined as having a transmittance of approximately 50% or more. "Transparent" is also used to mean colorless and transparent with respect to visible light. Visible light has a wavelength of approximately 360 nm to 830 nm and an energy of approximately 3.45 eV to 1.49 eV, and if the transmittance in this range is 50% or more, it is transparent.

Figures 1 to 3 show a photoelectric conversion element based on the first embodiment of the present invention. Figures 4 to 8 show a mobile phone equipped with a photoelectric conversion element according to the present invention as an example of an electronic device based on the first embodiment of the present invention.

Figure 1 is a plan view showing an example of a photoelectric conversion element. Figure 2 is a cross-sectional view taken along line I-I in Figure 1. Figure 3 is a cross-sectional view taken along line II-II in Figure 1. Figures 4 and 5 are bird's-eye views of a mobile phone incorporating a photoelectric conversion element. Figure 6 is a cross-sectional view taken along line I-I in Figures 4 and 5. Figure 7 is a plan view of the photoelectric conversion element incorporated in the mobile phone of Figures 4 and 5.

Figure 8 is a block diagram showing a photoelectric conversion element and a mobile phone. In the following description, "z-direction view" refers to a planar view, and "z-direction" refers to the thickness direction of the support substrate 1, etc.

As shown in FIG. 8, the mobile phone 14 includes a photoelectric conversion element 10 and a power control unit. The photoelectric conversion element is a power supply module in the mobile phone 14, and converts light such as sunlight or indoor light into electricity.

The mobile phone 14 is driven by power supplied from the photoelectric conversion element 10. The specific configuration and functions of the mobile phone 14 are not particularly limited, and various configurations capable of realizing the functions of a mobile phone may be adopted. Examples include an electronic calculation processing unit that realizes a mobile phone, a wireless communication unit that realizes the mobile phone 14 as a wireless communication module, an input/output calculation processing unit that can realize the mobile phone 14 as a portable electronic terminal device, etc.

The photoelectric conversion element of the present invention includes a support substrate 1, a first conductive layer 2, a second conductive layer 4, a photoelectric conversion layer 3, an adhesive 5, and an opposing substrate 6. In this embodiment, the photoelectric conversion element is rectangular when viewed in the z direction, but this is one example of the shape of an organic solar cell, and it can be set to various shapes.

The support substrate 1 serves as the base of the photoelectric conversion element. The support substrate 1 has a single layer or multiple layers made of a material appropriately selected from transparent glass or a film made of a resin such as PET. The thickness of the support substrate 1 is, for example, 0.05 mm to 2.0 mm. There are no particular limitations on the shape or size of the support substrate 1, and in this embodiment, it is rectangular when viewed in the z direction.

The photoelectric conversion element module has multiple exposed substrate areas formed therein, as shown in Figures 1 to 3.

The first conductive layer 2 is formed on a supporting substrate 1. It is preferable that the first conductive layer 2 has a light transmittance of 80% or more in the wavelength range of 400 to 700 nm. Examples of materials constituting the transparent electrode include metal oxides such as indium oxide, zinc oxide, tin oxide, indium tin oxide (ITO), fluorine-doped tin oxide (FTO), aluminum zinc oxide (AZO), and gallium zinc oxide (GZO); metals such as gold, platinum, silver, copper, tin, aluminum, molybdenum, titanium, tungsten, manganese, nickel, and cobalt, as well as metal nanoparticles and metal nanowires thereof; graphite, graphite intercalation compounds, carbon nanotubes, graphene, polyaniline and its derivatives, and polythiophene and its derivatives. Two or more of these may be contained, or a laminate structure of two or more layers composed of these materials may be used. The thickness of the transparent electrode is preferably 5 to 300 nm.

In this embodiment, the first conductive layer 2 is preferably made of silver nanowires. The first conductive layer 2 has a plurality of partitions. The shape of the first conductive layer 2 can be set to various shapes. The thickness of the first conductive layer 2 is, for example, 100 nm to 300 nm.

The multiple first partitions are adjacent to each other via the substrate exposed regions. In the present embodiment in FIG. 2, five first partitions are adjacent to each other via four substrate exposed regions. In addition, the five first partitions 15 are arranged in a straight line along the x direction.

The photoelectric conversion layer 3 is laminated on the support substrate 1 and the first conductive layer 2, and is sandwiched between the first conductive layer 2 and the second conductive layer 4. The photoelectric conversion layer 3 is a layer containing an organic material, and exhibits a photoelectric conversion function of converting received light into electric power. The specific configuration of the photoelectric conversion layer 3 is not particularly limited, but an example thereof is composed of an organic active layer, an electron transport layer laminated on the first conductive layer 2 side of the organic active layer, and a hole transport layer laminated on the second conductive layer 4 side. In this embodiment, the photoelectric conversion layer 3 has a rectangular shape, but this is just one example, and the photoelectric conversion layer 3 can have various shapes. The thickness of the photoelectric conversion layer 3 is, for example, 50 nm to 300 nm.

It is preferable that the photoelectric conversion layer 3 has a multi-layer structure with different functions, in order from the first conductive layer 2 side, an electron transport layer, a photoelectric conversion layer, and a hole transport layer.

Materials for forming the electron transport layer include, for example, metal oxides such as zinc oxide and titanium oxide, and organic materials with high electron transport properties such as Poly[(9,9-bis(3'-(N,N-dimethylamino)propyl)-2,7-fluorene)-alt-2,7-(9,9-dioctylfluorene)]: PFN and Polyethyleneimine, ethoxylated: PEIE. Two or more of these may be used. The thickness of the electron transport layer is preferably 0.5 to 50 nm.

Examples of materials for forming the hole transport layer include conductive polymers such as polythiophene polymers, poly-p-phenylene vinylene polymers, polyfluorene polymers, polypyrrole polymers, polyaniline polymers, polyfuran polymers, polypyridine polymers, and polycarbazole polymers, low molecular weight organic compounds exhibiting p-type semiconductor properties such as phthalocyanine derivatives (H2Pc, CuPc, ZnPc, etc.), porphyrin derivatives, and acene compounds (tetracene, pentacene, etc.), carbon compounds such as graphene and graphene oxide, and inorganic materials such as molybdenum oxide, tungsten oxide, nickel oxide, vanadium oxide, and zirconium oxide. Two or more of these may be used. Among these, PEDOT:PSS, in which polystyrene sulfonic acid (PSS) is added to polyethylene dioxythiophene (PEDOT), which is a polythiophene polymer, is preferred. The thickness of the hole transport layer is preferably 0.5 to 50 nm in order to have an appropriate hole transport ability.

The organic active layer according to the present invention contains at least one material having an organic structure. Examples of photoelectric conversion elements having such an organic active layer include perovskite-type solar cells having an organic halide perovskite in the photoelectric conversion layer, dye-sensitized solar cells having a photoelectric conversion layer composed of an organic material dye and an inorganic semiconductor such as titanium oxide, and organic thin-film solar cells having a photoelectric conversion layer composed of an electron-donating organic material and an electron-accepting organic material. Organic thin-film solar cells are particularly suitable for the present invention because the penetration part of the photoelectric conversion layer can be easily processed.

In the case of an organic thin-film solar cell in which the organic active layer is composed of an electron-donating organic material and an electron-accepting organic material, the electron-donating organic material and the electron-accepting organic material may be two or more kinds. Examples of the structure of the organic active layer include a structure consisting of a layer containing a mixture of an electron-donating organic material and an electron-accepting organic material, a structure in which a layer consisting of an electron-donating organic material and a layer consisting of an electron-accepting organic material are laminated, and a structure in which a layer consisting of the mixture is laminated between a layer consisting of an electron-donating organic material and a layer consisting of an electron-accepting organic material. Among these, a structure consisting of a layer containing a mixture of an electron-donating organic material and an electron-accepting organic material is preferred. The content ratio of the electron-donating organic material and the electron-accepting organic material is not particularly limited, but it is preferable that the electron-donating organic material:electron-accepting organic material (donor-acceptor ratio) is in the range of 10:90 to 60:40.

The electron-donating organic material is not particularly limited as long as it is an organic compound that exhibits p-type semiconductor properties. For example, conjugated polymers such as polythiophene polymers, benzothiadiazole-thiophene copolymers, quinoxaline-thiophene copolymers, thiophene-benzodithiophene copolymers, poly-p-phenylenevinylene polymers, poly-p-phenylene polymers, polyfluorene polymers, polypyrrole polymers, polyaniline polymers, polyacetylene polymers, and polythienylenevinylene polymers, phthalocyanine derivatives such as H2 phthalocyanine, copper phthalocyanine, and zinc phthalocyanine, porphyrin derivatives, triarylamine derivatives, carbazole derivatives, and oligothiophene derivatives (terthiophene, quarterthiophene, sexithiophene, octithiophene, etc.), and other low molecular weight organic compounds may be used. Two or more of these may be used. Among the conjugated polymers having the above-mentioned backbone structures, conjugated polymers having a structure represented by the following general formula (1) are preferred because they have a wide light absorption wavelength range and a deep HOMO level, resulting in high photoelectric conversion characteristics.

In the above general formula (1), n represents an integer of 1 or more. The number average molecular weight of the conjugated polymer having the structure represented by the general formula (1) is preferably 30,000 to 60,000.

The electron-accepting organic material is not particularly limited as long as it is an organic material that exhibits n-type semiconductor properties. For example, fullerene derivatives, which are stable n-type semiconductors with high carrier mobility, are preferably used. Examples of fullerene derivatives include unsubstituted fullerenes such as C60, C70, C76, C78, C82, C84, C90, and C94, and substituted fullerene derivatives with improved solubility in organic solvents such as [6,6]-Pheyl-C61-Butyric Acid Methyl Ester: 60PCBM and [6,6]-Pheyl-C71-Butyric Acid Methyl Ester: 70PCBM. Two or more of these may be used.

The thickness of the organic active layer should be sufficient for the electron donating organic material and the electron accepting organic material to cause photoelectric conversion by absorbing light, and although it varies depending on the material, a thickness of 50 nm to 500 nm is preferable.

The second conductive layer 4 does not need to be optically transparent, and from the viewpoint of improving the amount of power generation, a conductive material that has a high optical reflectance, particularly in the visible light region, and forms an ohmic junction with the hole transport layer is preferable. For example, metals such as gold, platinum, silver, copper, iron, zinc, tin, aluminum, indium, chromium, nickel, and cobalt, as well as metal nanoparticles and metal nanowires thereof, graphite, graphite intercalation compounds, carbon nanotubes, graphene, polyaniline and its derivatives, polythiophene and its derivatives, etc. are preferable. Two or more of these may be used. The thickness of the counter electrode is not particularly limited as long as it is conductive. Most of the second conductive layer 4 is laminated on the first conductive layer 2 via the photoelectric conversion layer 3. In addition, a part of the second conductive layer 4 is in direct contact with the first conductive layer 2.

First, as shown in FIG. 9-1, a first conductive layer 2 is formed by depositing silver nanowires on one side of a support substrate 1 using a general method such as spin coating. Next, the first conductive layer 2 is patterned to form an exposed substrate region and obtain a plurality of partitions. As a patterning method for the first conductive layer 2, a method using wet etching, or a method using laser patterning such as UV laser light, Green laser light, or IR laser light is appropriately adopted. In this embodiment, UV laser light is used as the laser light Lz.

Next, as shown in FIG. 9-1, the photoelectric conversion layer 3 is formed. The photoelectric conversion layer 3 is formed, for example, by forming an organic film on the support substrate 1 and the first conductive layer 2 by spin coating. Next, a photoelectric conversion layer penetration portion is formed in the photoelectric conversion layer 3. The photoelectric conversion layer penetration portion is formed, for example, by laser patterning. The laser light Lz used in this laser patterning is appropriately selected so that it can partially remove the photoelectric conversion layer penetration portion. In this embodiment, an example will be described in which laser patterning is performed using UV laser light as the laser light Lz. In this case, the laser light Lz removes both the photoelectric conversion layer 3 and the first conductive layer 2. Therefore, a photoelectric conversion layer penetration portion is formed in the photoelectric conversion layer 3, and a first conductive layer penetration portion is also formed in the first conductive layer 2. Through this patterning, the first conductive layer 2 and the photoelectric conversion layer 3 are obtained. In addition, as the laser light Lz forms the photoelectric conversion layer penetration portion and the first conductive layer penetration portion, protrusions may be formed in the photoelectric conversion layer 3 in a shape that surrounds the photoelectric conversion layer penetration portion. Such protrusions may hinder the formation of a uniform second conductive layer 4 and increase the resistance between the second conductive layer 4 and the first conductive layer 2. In addition, such protrusions may cause fine cracks in the adhesive layer or protective layer, for example, and may cause the photoelectric conversion element to deteriorate due to the intrusion of moisture, etc.

As shown in FIG. 9-2, the penetrations between the photoelectric conversion layer and the first conductive layer 2 are filled with a material of the same quality as the first conductive layer 2, and the first conductive layer 2 is formed so as to be thicker than the photoelectric conversion layer 3. The filling method is not particularly limited, but an inkjet method that allows precise application is preferably used. When filling with a material of the same quality as the first conductive layer 2, the protrusions formed to surround the penetrations of the photoelectric conversion layer can be properly covered. By covering the protrusions, the second conductive layer 4 is formed uniformly, the second conductive layer 4 and the first conductive layer 2 are in proper contact, and the resistance between the second conductive layer 4 and the first conductive layer 2 can be reduced. In addition, cracks in the layer structure caused by the protrusions and deterioration of the photoelectric conversion element can be prevented.

Next, the second conductive layer 4 is formed. The second conductive layer 4 is formed by depositing a metal film on the support substrate 1, the first conductive layer 2, and the photoelectric conversion layer 3 using, for example, the above-mentioned metal by a deposition method such as electron beam deposition. The thickness of the deposited film is not particularly limited, but a thinner film is preferable from the viewpoint of the amount of material used, for example, 10 to 200 nm. The metal film can be patterned by, for example, etching using a mask layer. This patterning forms the second conductive layer 4 having a plurality of partitions on the first conductive layer 2 and the photoelectric conversion layer 3. Thereafter, the opposing substrate 6 is attached with an adhesive 5. Through the above steps, a photoelectric conversion element is obtained.

In this way, after forming the through-holes in the photoelectric conversion layer and the first conductive layer using the laser light Lz, the first conductive layer 2 is formed to be partially thicker than the photoelectric conversion layer 3 and to cover the protrusions, thereby reducing the series resistance of the junction and improving the photoelectric conversion efficiency of the photoelectric conversion element.

When, for example, UV laser light is used as the laser light Lz shown in FIG. 9-1, the photoelectric conversion layer penetration portion and the first conductive layer penetration portion are formed collectively. The photoelectric conversion layer penetration portion and the first conductive layer penetration portion are formed by a through hole having a diameter of, for example, about 40 μm. This UV laser light can remove the first conductive layer 2 made of, for example, silver nanowires, and can therefore be used as the laser light Lz in the laser patterning of the first conductive layer 2 shown in FIG. 9-1. As a result, in the manufacturing method of the organic thin-film solar cell shown in FIG. 9-1, it is sufficient to use one type of laser light (UV laser light) as the laser light Lz. This is favorable for simplifying the manufacturing method and manufacturing equipment, and contributes to shortening the manufacturing time.

In the example of Figures 1 and 2, four sets of partitions (cells) consisting of a first conductive layer, a photoelectric conversion layer, and a second conductive layer are formed on a support substrate 1. As shown in Figure 1, by providing two or more connection points between two adjacent cells, the series resistance between the cells can be reduced. Furthermore, even if the conductivity at one connection point becomes inappropriate, the adjacent partitions can be properly connected by the other connection point.

Examples of driving units that are driven by power supplied from the photoelectric conversion element of the present invention include displays, sensors, wireless communication units, and input/output calculation processing units.

In addition, electronic devices equipped with the photoelectric conversion element according to the present invention and a drive unit that is driven by power supplied from the photoelectric conversion element include mobile phones, wristwatches, electronic calculators, etc.

The photoelectric conversion element, electronic device, and method for manufacturing a photoelectric conversion element according to the present invention are not limited to the above-described embodiments. The specific configurations of the electronic device and method for manufacturing a photoelectric conversion element according to the present invention can be freely designed in various ways.

The present invention will be specifically explained below with reference to examples, but the present invention is not limited to these.

The evaluation method for each example and comparative example will be described below. First, for the organic thin-film solar cells produced in each example and comparative example, the power generation efficiency and power generation per unit area of the effective power generation area under simulated sunlight of 1 SUN (1000 W/m2) and a daylight white LED of 200 Lux were measured and used as the initial characteristics.

(Example)
A photoelectric conversion element having the structure shown in FIGS. 10-1 and 10-2 was fabricated by the following procedure.

(Formation of photoelectric conversion element)
A transparent barrier film (manufactured by Reiko Co., Ltd., "Belair" (registered trademark) "50M006-3HT" (product name)) was used as the support substrate 1. Next, the barrier film was dry washed and subjected to hydrophilization treatment by surface modification under reduced pressure at 300 W for 100 seconds using a plasma etcher (manufactured by Sakigake Semiconductor Co., Ltd., CPM-400M (product name)).

Next, the first conductive layer 1 was formed by the inkjet method. The ink for the first conductive layer was prepared by mixing 9 ml of silver nanowire ink (manufactured by Seiko PMC Co., Ltd., "T-AG134" (product name)), 0.5 ml of ethanol (manufactured by Wako Pure Chemical Industries, Ltd.), and 0.5 ml of ethylene glycol (manufactured by Wako Pure Chemical Industries, Ltd.), and then mixing by hand shaking. The prepared ink was filtered using a 5.0 μm pole PTFE syringe filter and filled into a dedicated cartridge DMC-11610 of an inkjet device (manufactured by Fujifilm Corporation, "Material Printer DMP-2850"). Inkjet printing was performed using a 10 pL head under the following conditions: head temperature: room temperature, stage temperature: 30°C, head ejection voltage: 30 V, printing pitch: 30 μm, and number of scans: 1. After that, the film was dried by heating at 100°C for 2 minutes under reduced pressure in a vacuum dryer (manufactured by Reimac Co., Ltd.), obtaining a first conductive layer with a film thickness of 100 nm and a sheet resistance of 10 Ω/□.

Next, to create partitions in the first conductive layer, an insulating pattern was formed using a UV laser with a wavelength of 355 nm, output of 80 mW, sweep speed of 600 mm/sec, and frequency of 60 kHz in a laser processing machine ("HWS-UI" manufactured by Toray Engineering Co., Ltd.).

Next, the electron transport layer 31 was formed by the inkjet method. 1.75 g of zinc acetate dihydrate (manufactured by Wako Pure Chemical Industries, Ltd.) and PEIE (80% ethoxylated solution, 37 wt.% in H2O) (manufactured by Sigma-Aldrich) were added to a sample bottle containing 47.5 mL of 1-Butanol (manufactured by Wako Pure Chemical Industries, Ltd.) and 2.5 mL of ethylene glycol (manufactured by Wako Pure Chemical Industries, Ltd.), and the mixture was stirred at 30°C, 1500 rpm, and 60 minutes to obtain an electron transport layer ink. The prepared ink was filtered with a 0.45 μm Pole PTFE syringe filter and filled into a dedicated cartridge DMC-11610 of an inkjet device (manufactured by Fujifilm Corporation, "Material Printer DMP-2850"). On the substrate on which the first conductive layer was formed, an inkjet film was formed using a 10 pL head under the following conditions: head temperature: 30°C, stage temperature: 30°C, head ejection voltage: 16V, printing pitch: 30 μm, and number of scans: 1. The film was then dried by heating at 100°C for 2 minutes under reduced pressure in a vacuum dryer (manufactured by Raymac Co., Ltd.), and further heated and converted on a hot plate at a temperature of 150°C for 30 minutes to form an electron transport layer. The film thickness of the electron transport layer after drying was 40 nm.

Next, the organic active layer 32 was formed by the inkjet method. 33.75 mg of a conjugated polymer (number average molecular weight: 45,900, weight average molecular weight: 106,000, Z average molecular weight: 247,000) having the structure represented by the general formula (1), 41.25 mg of [6,6]-phenyl C61 butyric acid methyl ester (PCBM) (manufactured by Frontier Carbon Co., Ltd.), and 10 ml of tetralin were placed in a sample bottle and stirred at 30°C, 1500 rpm, and 60 minutes to obtain an organic active layer ink. The ink thus prepared was filtered through a 5.0 μm Pole PTFE syringe filter onto the substrate on which the electron transport layer was formed, and then filled into a dedicated cartridge DMCLCP-11610 of an inkjet device (manufactured by Fujifilm Corporation, "Material Printer DMP-2850"). On the substrate on which the first conductive layer was formed, an inkjet film was formed using a 10 pL head under the following conditions: head temperature: 40°C, stage temperature: 30°C, head ejection voltage: 18V, printing pitch: 20μm, and number of scans: 1. After that, the organic active layer was formed by heating and drying at 100°C for 2 minutes under reduced pressure in a vacuum dryer (manufactured by Raymac Co., Ltd.). The film thickness of the organic active layer after drying was 250 nm.

Next, the hole transport layer 33 was formed by the inkjet method. The ink for the hole transport layer was prepared by mixing 35 ml of polyethylenedioxythiophene polystyrene sulfonate (PEDOT:PSS, Agfa Materials Japan, "Orgacon IJ005" (registered trademark)) with 15 ml of pure water in which a surfactant (Kao Corporation, "Emulgen" (registered trademark) 108 (product name)) was diluted to 10 g/L, and then mixing was performed by hand shaking. The prepared ink was filtered using a 5.0 μm Pole PTFE syringe filter and filled into a dedicated cartridge DMC-11610 of an inkjet device (FUJIFILM Corporation, "Material Printer DMP-2850"). Inkjet printing was performed using a 10 pL head under the following conditions: head temperature: room temperature, stage temperature: 30°C, head ejection voltage: 30 V, printing pitch: 10 μm, and number of scans: 1. After that, the film was dried by heating at 100°C for 2 minutes under reduced pressure using a vacuum dryer (manufactured by Reimac Co., Ltd.) to obtain a hole transport layer with a thickness of 40 nm.

Next, to provide a penetration through the photoelectric conversion layer, a UV laser with a wavelength of 355 nm, output of 80 mW, sweep speed of 600 mm/sec, and frequency of 60 kHz was used to form a penetration through the photoelectric conversion layer in a laser processing machine ("HWS-UI" manufactured by Toray Engineering Co., Ltd.). At the same time, a penetration through the transparent conductive film below the photoelectric conversion layer was also formed by the laser processing.

Next, the first conductive layer 1 was additionally formed in the through-hole by the inkjet method. The ink for the first conductive layer was prepared by mixing 9 ml of silver nanowire ink (manufactured by Seiko PMC Co., Ltd., "T-AG134" (product name)), 0.5 ml of ethanol (manufactured by Wako Pure Chemical Industries, Ltd.), and 0.5 ml of ethylene glycol (manufactured by Wako Pure Chemical Industries, Ltd.), and then mixing by hand shaking. The prepared ink was filtered using a 5.0 μm pole PTFE syringe filter, and filled into a dedicated cartridge DMC-11610 of an inkjet device (manufactured by Fujifilm Corporation, "Material Printer DMP-2850"). Inkjet printing was performed using a 10 pL head under the following conditions: head temperature: room temperature, stage temperature: 30°C, head ejection voltage: 30 V, printing pitch: 30 μm, and number of scans: 10 times. After that, the coating was dried by heating at 100°C for 2 minutes under reduced pressure using a vacuum dryer (manufactured by Reimac Co., Ltd.) to obtain a first conductive layer with a thickness of 1 μm.

Next, the second conductive layer 4 was formed by vacuum deposition. The substrate on which the first conductive layer and the photoelectric conversion layer consisting of the electron transport layer/organic active layer/hole transport layer were formed, and an electrode mask were placed in a vacuum deposition apparatus, and the apparatus was evacuated until the degree of vacuum inside the apparatus reached 1×10 ⁻³ Pa or less, and silver was formed to a thickness of 200 nm by deposition using a resistance heating method. The area where the first conductive layer and the second conductive layer overlap is the effective power generation area of the photoelectric conversion element.

The photoelectric conversion efficiency and power generation amount per unit area of the effective power generation area of the fabricated photoelectric conversion element were evaluated using various light sources. The photoelectric conversion efficiency was 3.5% under pseudo solar light of 1 SUN (1000 W/m2) and 7.4 μW/ ^cm2 under a daylight LED of 200 Lux.

Comparative Example
In the above-mentioned embodiment, a photoelectric conversion element was produced in which the first conductive layer 1 was not additionally formed in the through portion by the inkjet method.

The photoelectric conversion element thus fabricated was evaluated for its photoelectric conversion efficiency and power generation per unit area of the effective power generation area using various light sources. It was found that the photoelectric conversion element did not have electrical continuity, and power generation characteristics could not be confirmed with either simulated sunlight of 1 sun (1000 W/m2) or a daylight white LED of 200 Lux.

Reference Signs List 1 Support substrate 2 First conductive layer 3 Photoelectric conversion layer 31 Electron transport layer 32 Organic active layer 33 Hole transport layer 4 Second conductive layer 5 Adhesive 6 Opposing substrate 7 First cover 8 Display 9 Electronic circuit board 10 Photoelectric conversion element 11 Battery 12 Second cover 13 Peripheral frame 14 Mobile phone H Thickness of mobile phone
15 First partition 16 Second partition 17 Photoelectric conversion layer penetration portion 18 Protrusion surrounding the photoelectric conversion layer penetration portion 19 Drive portion driven by power supply 20 Substrate exposed area

Claims (7)

A photoelectric conversion element comprising a transparent support substrate, a transparent first conductive layer and a second conductive layer stacked on the support substrate, and a photoelectric conversion layer containing an organic material sandwiched between the first conductive layer and the second conductive layer, a portion of the first conductive layer being thicker than the photoelectric conversion layer, the first conductive layer having two first partitions adjacent to each other via a substrate exposed region where a portion of the support substrate is exposed from the first conductive layer, the second conductive layer having two second partitions adjacent to each other across a portion of the substrate exposed region, and the photoelectric conversion layer having a photoelectric conversion layer penetration portion penetrating through the thickness direction at a photoelectric conversion layer connection portion that overlaps with both one of the two adjacent first partitions and the other of the two adjacent second partitions in a planar view. The photoelectric conversion element according to claim 1, wherein the active layer of the photoelectric conversion layer is composed of an electron donating organic material and an electron accepting organic material. The photoelectric conversion element according to claim 1, wherein the photoelectric conversion layer has a protrusion surrounding the photoelectric conversion layer penetration portion in a plan view, and the protrusion is covered by the first conductive layer. The method for manufacturing a photoelectric conversion element according to claim 1, wherein in the step of stacking the photoelectric conversion layers, a photoelectric conversion layer penetration portion is formed penetrating the photoelectric conversion layers, and the photoelectric conversion layer penetration portion is covered by the first conductive layer. The method for manufacturing a photoelectric conversion element according to claim 4, wherein in the step of laminating the first conductive layer, a transparent electrode is laminated by an inkjet method. The method for manufacturing a photoelectric conversion element according to claim 4 or 5, wherein the first conductive layer is made of silver nanowires. 4. An electronic device comprising the photoelectric conversion element according to claim 1 and a drive section that is driven by power supplied from the photoelectric conversion element.