Method of manufacturing grooved transparent electrode and method of manufacturing solar cell element

Abstract

To provide a manufacturing method of a grooved transparent electrode and a manufacturing method of a solar cell element capable of suppressing manufacturing cost while suppressing generation of burrs.SOLUTION: The method includes a step of forming a side P1 of a groove structure by irradiating an indium tin oxide layer 101 provided on a transparent substrate 100 with laser light having an irradiating energy density of 1.9 * 10 - 1J / mm2 or less. Further, in the method of manufacturing the grooved transparent electrodes according to the present invention, the radiation energy density of the laser beam is preferably 3.8 * 10 - 2J / mm2 or more, and more preferably 1.3 * 10 - 1J / mm2 or less.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to a method for manufacturing a grooved transparent electrode and a method for manufacturing a solar cell element. [Background technology]

[0002] Indium tin oxide (ITO) is used as a conductive transparent electrode in a solar cell element. Patent Document 1 discloses a method for manufacturing a solar cell element using wet etching or dry etching as a method for patterning an electrode of an indium tin oxide film. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2014-030004 Summary of the Invention [Problem to be solved by the invention]

[0004] When patterning an ITO film formed on a transparent substrate by wet etching, as in the technique described in Patent Document 1, there are problems with long processing times and high costs. On the other hand, when patterning an ITO film formed on a transparent substrate by irradiating it with laser light as an alternative to wet etching, there is a problem with burrs being generated in the patterned transparent electrode.

[0005] In other words, there is a problem in patterning an ITO film in that it is not possible to suppress the occurrence of burrs while suppressing manufacturing costs. Patent Document 1 does not disclose any technology that can solve this problem.

[0006] The present disclosure has been made to solve such problems, and aims to provide a method for manufacturing a grooved transparent electrode and a method for manufacturing a solar cell element that can suppress the occurrence of burrs while reducing manufacturing costs. [Means for solving the problem]

[0007] The method for producing a grooved transparent electrode according to the present disclosure is carried out by applying an irradiation energy density of 1.9×10 to an indium tin oxide layer provided on a transparent substrate. -1 J / mm 2 The method for manufacturing a grooved transparent electrode includes the step of forming a groove structure by irradiating a laser beam as follows.

[0008] This configuration can suppress the generation of burrs caused by laser light irradiation, and as a result, the method for manufacturing a grooved transparent electrode according to the present disclosure can reduce manufacturing costs while suppressing the generation of burrs.

[0009] In the method for producing a grooved transparent electrode according to the present disclosure, the irradiation energy density of the laser beam is 3.8×10 -2 J / mm 2 With this configuration, the method for manufacturing a transparent electrode according to the present disclosure can appropriately form a groove structure.

[0010] In the method for manufacturing a grooved transparent electrode according to the present disclosure, the irradiation energy density of the laser beam is 1.3×10 -1 J / mm 2 According to this configuration, the method for manufacturing a transparent electrode according to the present disclosure can further suppress the occurrence of burrs in the groove structure.

[0011] In the method for manufacturing a grooved transparent electrode according to the present disclosure, the depth of the groove structure may be 200 nm or less. With this configuration, the method for manufacturing a transparent electrode according to the present disclosure can form the groove structure by irradiating laser light once. As a result, the method for manufacturing a transparent electrode according to the present disclosure can reduce manufacturing costs.

[0012] The method for manufacturing a solar cell element according to the present disclosure is to irradiate an indium tin oxide layer provided on a transparent substrate with an irradiation energy density of 1.9×10 -1 J / mm 2 The method for manufacturing a solar cell element includes the steps of forming a groove structure by irradiating a laser beam as follows, depositing a first carrier transport layer, and depositing a second carrier transport layer.

[0013] With this configuration, the manufacturing method of a solar cell element according to the present disclosure can suppress the occurrence of short circuits due to burrs in the manufactured solar cell element, and as a result, the manufacturing method of a solar cell element according to the present disclosure can suppress an increase in shunt resistance in the manufactured solar cell element, thereby improving the photoelectric conversion efficiency.

[0014] In the method for manufacturing a solar cell element according to the present disclosure, a solar cell may be manufactured in which the distance from the indium tin oxide layer to the second carrier transport layer is 184 nm or more. When manufacturing a solar cell with such a configuration, the occurrence of short circuits due to burrs can be further suppressed, and therefore the method for manufacturing a solar cell element according to the present disclosure is particularly effective.

[0015] The method for manufacturing a solar cell element according to the present disclosure may also manufacture a solar cell in which the distance from the indium tin oxide layer to the second carrier transport layer is 598 nm or less. The method for manufacturing a solar cell element according to the present disclosure can suppress the size of burrs to less than 598 nm, and is therefore particularly effective when manufacturing a solar cell with such a configuration.

[0016] The method for manufacturing a solar cell element according to the present disclosure may be used to manufacture a solar cell in which the first carrier transport layer is a hole transport layer containing an organic compound. When manufacturing a solar cell having such a configuration, the method for manufacturing a solar cell element according to the present disclosure is particularly effective. [Effects of the Invention]

[0017] The present disclosure can provide a method for manufacturing a grooved transparent electrode and a method for manufacturing a solar cell element that can suppress the occurrence of burrs while reducing manufacturing costs. [Brief explanation of the drawings]

[0018] [Figure 1] FIG. 2 is a cross-sectional view showing the configuration of a grooved transparent electrode according to the first embodiment. [Figure 2] FIG. 1 is a cross-sectional view showing the configuration of a solar cell element according to a first embodiment. [Figure 3] 3 is a flowchart showing a method for manufacturing a solar cell element according to the first embodiment. [Figure 4] FIG. 2 is a cross-sectional view illustrating a method for manufacturing a solar cell element according to the first embodiment. [Figure 5] FIG. 10 is a cross-sectional view showing the configuration of a transparent electrode in which burrs are generated. [Figure 6] FIG. 10 is a cross-sectional view showing the configuration of a solar cell element in which burrs have occurred. [Figure 7] FIG. 2 is a cross-sectional view illustrating a method for manufacturing a solar cell element according to the first embodiment. [Figure 8] FIG. 2 is a cross-sectional view illustrating a method for manufacturing a solar cell element according to the first embodiment. [Figure 9] 10A and 10B are cross-sectional views for explaining a method for manufacturing a solar cell element according to a comparative example. [Figure 10] 10 is a graph showing the relationship between the irradiation energy density of laser light and the height of burrs according to an example and a comparative example. [Figure 11] 1A and 1B are top views obtained by tracing photographs of grooved transparent electrodes according to examples and comparative examples. [Figure 12] 1A and 1B are top views obtained by tracing photographs of hole transport layers according to examples and comparative examples. DETAILED DESCRIPTION OF THE INVENTION

[0019] First Embodiment (Structure of grooved transparent electrode) DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS First, the configuration of a grooved transparent electrode according to the present embodiment will be described in detail. Naturally, the right-handed xyz Cartesian coordinate system shown in Figure 1 and other drawings is for the convenience of explaining the positional relationships of the components. Normally, the positive direction of the z axis is vertically upward, and the xy plane is the horizontal plane, which is common among the drawings.

[0020] Fig. 1 is a cross-sectional view showing the configuration of a grooved transparent electrode according to the first embodiment. More specifically, Fig. 1 is a cross-sectional view of the grooved transparent electrode according to the first embodiment cut along a plane perpendicular to the main surface.

[0021] The grooved transparent electrode 1 according to this embodiment is a plate-like or film-like member that has conductivity on at least one surface and transmits at least visible light. The grooved transparent electrode 1 according to this embodiment is used as a substrate and an electrode layer for, for example, a solar cell element, a light emitting element, a touch panel, or the like.

[0022] The transparent electrode 1 comprises a transparent substrate 100 and an indium tin oxide layer 101 . The transparent substrate 100 is a plate-like or film-like member, and has an indium tin oxide layer 101 on at least one surface.

[0023] As will be described in detail later, in the grooved transparent electrode according to this embodiment, the groove structure P1 is formed by removing a part of the indium tin oxide layer 101 by irradiating it with laser light. Therefore, the transparent substrate 100 is preferably made of a heat-resistant material that can withstand laser light irradiation, such as heat-resistant glass. When the transparent substrate 100 is made of glass, the transparent electrode 1 is sometimes called an ITO glass substrate.

[0024] The indium tin oxide layer 101 is a layer formed on at least one surface of the transparent substrate 100, and contains a mixture of indium oxide and tin oxide as its main components. The indium tin oxide layer 101 is a film that is transparent to visible light and electrically conductive, and functions as an electrode layer when applied to, for example, a solar cell element, a light emitting element, a touch panel, or the like. Here, the indium tin oxide layer 101 is divided into a plurality of regions via a groove structure P1, and each region is electrically insulated.

[0025] The groove structures P1 are grooves provided in the indium tin oxide layer 101. The groove structures P1 are linear grooves extending parallel to the y-axis in Fig. 1, and divide the indium tin oxide layer 101 into a plurality of regions. 1, the groove structure P1 is formed by removing a portion of the indium tin oxide layer 101 on the transparent substrate 100. Therefore, the indium tin oxide layer 101 is divided into multiple regions by the groove structure P1, and each region is appropriately electrically insulated from the other regions.

[0026] Although details will be described later, the manufacturing method of the grooved transparent electrode according to this embodiment has technical features in the process of forming the groove structure P1, and by incorporating these technical features, it is possible to reduce manufacturing costs while suppressing the occurrence of burrs in the groove structure P1.

[0027] (Configuration of solar cell element) Next, the configuration of the solar cell element according to this embodiment will be described in detail. The solar cell element 10 according to this embodiment is a solar cell element that includes the transparent electrode 1 according to this embodiment as a component. That is, the solar cell element 10 according to this embodiment is a specific example of a product to which the transparent electrode 1 according to this embodiment is applied.

[0028] 2 is a cross-sectional view showing the configuration of the solar cell element according to the first embodiment, more specifically, a cross-sectional view of the grooved transparent electrode according to the first embodiment cut along a plane perpendicular to the main surface. In Fig. 2, sunlight is incident from the negative direction of the z axis to the positive direction of the z axis. Arrow I in Fig. 2 indicates part of the current flowing in the solar cell element.

[0029] The solar cell element 10 according to this embodiment is a perovskite solar cell, and as shown in FIG. 2, is an integrated solar cell. In the solar cell element 10, the transparent substrate 100 functions as the substrate of the solar cell element, the indium tin oxide layer 101 functions as the transparent electrode layer of the solar cell element, and the groove structure P1 functions as a P1 scribe of the integrated solar cell.

[0030] It should be noted that the solar cell element according to the present disclosure is not limited to a perovskite solar cell element, and may be, for example, a silicon solar cell element or a cuprous oxide solar cell element.

[0031] As will be described in detail later, the method for manufacturing a solar cell element according to the present disclosure can suppress the generation of burrs in the indium tin oxide layer. More specifically, the method for manufacturing a solar cell element according to the present disclosure can suppress the size of burrs in the indium tin oxide layer so that the size is smaller than the distance between the indium tin oxide layer and the carrier transport layer in a thin-film solar cell.

[0032] Therefore, the method for manufacturing a solar cell element according to the present disclosure can suppress short circuits even when applied to thin-film solar cells, which are particularly susceptible to short circuits due to the generation of burrs. In other words, the method for manufacturing a solar cell element according to the present disclosure is particularly effective when applied to thin-film solar cells such as perovskite solar cells, CIS solar cells, cuprous oxide solar cells, and amorphous silicon solar cells.

[0033] The solar cell element 10 includes a first carrier transport layer 102, a photoelectric conversion layer 103, a second carrier transport layer 104, and a counter electrode layer 105 on a transparent electrode 1. The first carrier transport layer 102, the photoelectric conversion layer 103, the second carrier transport layer 104, and the counter electrode layer 105 are divided into a plurality of regions by a groove structure P3.

[0034] By dividing the solar cell element 10 into multiple regions via the groove structures P1 and P3 in this way, the current flowing inside the solar cell element 10 flows electrically in series between adjacent regions. With this configuration, the solar cell element according to this embodiment has an improved output voltage. That is, the solar cell element 10 according to this embodiment is integrated by the groove structures P1 and P3.

[0035] It should be understood that the scribing pattern shown in FIG. 2 is merely an example, and solar cell elements according to the present disclosure may be integrated using a scribing pattern different from that shown in FIG.

[0036] The photoelectric conversion layer 103 absorbs sunlight incident from the negative side of the z axis to excite electrons and generate holes and conduction electrons. As described above, holes generated in the photoelectric conversion layer 103 are collected in the indium tin oxide layer 101 via the first carrier transport layer 102, and conduction electrons generated in the photoelectric conversion layer 103 are collected in the counter electrode layer 105 via the first carrier transport layer 102.

[0037] The photoelectric conversion layer 103 according to this embodiment contains a perovskite compound as a main component and may contain appropriate additives, etc. The perovskite compound referred to here refers to a group of compounds that have a perovskite-type crystal structure.

[0038] An example of a compound that can be used as the main component of the photoelectric conversion layer 103 is a perovskite compound represented by the composition formula (1) below. AMX3...Formula (1) where A is a monovalent cation, M is a divalent cation, and X is a monovalent anion.

[0039] In this embodiment, the first carrier transport layer 102 is a hole transport layer (HTL), and the second carrier transport layer 104 is an electron transport layer (ETL). In other words, the solar cell element according to this embodiment is an inverted structure solar cell element.

[0040] It should be noted that the solar cell elements that can be manufactured by the solar cell element manufacturing method according to the present disclosure are not limited to those with an inverted structure, and that the solar cell element manufacturing method according to the present disclosure can also be applied to the manufacture of solar cell elements with a forward structure.

[0041] As described above, the first carrier transport layer 102 is a hole transport layer (HTL). One surface of the first carrier transport layer 102 is in contact with the indium tin oxide layer 101, and the other surface of the first carrier transport layer 102 is in contact with the photoelectric conversion layer 103.

[0042] The first carrier transport layer 102 extracts holes generated in the photoelectric conversion layer 103 and transports them to the indium tin oxide layer 101, which functions as an electrode layer. In other words, the holes generated in the photoelectric conversion layer 103 flow into the indium tin oxide layer 101 via the first carrier transport layer 102.

[0043] Examples of compounds that can be used as the main component of the first carrier transport layer 102 include polythiophene-based materials such as PEDOT:PSS (poly(3,4-ethylenedioxythiophene):poly(styrenesulfonic acid) composite), arylamine-based materials such as PTAA (PolyTriArylAmine), and indole-based materials such as PATAT (Phosphonic Acid functionalized TriAzaTruxene).

[0044] In addition, when a solar cell element having a normal structure is manufactured, a general hole transport material can be used for the hole transport layer. Examples of materials for the hole transport layer when manufacturing a normal structure solar cell element include compounds having a spiro structure such as Spiro-OMeTAD, and arylamine-based materials such as PTAA (PolyTriArylAmine).

[0045] As described above, the second carrier transport layer 104 is an electron transport layer (ETL). The first carrier transport layer 102 is in contact with the counter electrode layer 105 on one side and is in contact with the photoelectric conversion layer 103 on the other side.

[0046] The second carrier transport layer 104 extracts the conduction electrons generated in the photoelectric conversion layer 103 and transports them to the counter electrode layer 105. In other words, the conduction electrons generated in the photoelectric conversion layer 103 flow to the counter electrode layer 105 via the second carrier transport layer 104.

[0047] Examples of compounds that can be used as the main component of the second carrier transport layer 104 include fullerene C 60 and phenyl C 61 Butyric acid methyl ester (PCBM), [6,6]-Phenyl-C 61 -Butyric acid methyl ester) and other fullerene derivatives.

[0048] In addition, when a solar cell element having a normal structure is manufactured, a general electron transport material can be used for the electron transport layer. Examples of materials for the electron transport layer when manufacturing a normal structure solar cell element include inorganic oxides such as titanium oxide and tin oxide.

[0049] In the solar cell element 10 according to this embodiment, the distance from the indium tin oxide layer 101 to the second carrier transport layer 104 is 184 nm or more and 598 nm or less. Although details will be described later, by using the method for manufacturing a solar cell element according to this embodiment, the size of burrs generated in the indium tin oxide layer 101 can be reduced to approximately 184 nm. Therefore, if the distance from the indium tin oxide layer 101 to the second carrier transport layer 104 is 184 nm or more, the solar cell element 10 according to this embodiment can suppress short circuits, resulting in improved cell performance.

[0050] Furthermore, when the distance from the indium tin oxide layer 101 to the second carrier transport layer 104 is 598 nm, the solar cell element 10 is strongly affected by short circuits caused by burrs that occur in the indium tin oxide layer 101. Therefore, the method for manufacturing a solar cell element according to the present disclosure, which can reduce the size of burrs that occur in the indium tin oxide layer 101, is particularly effective when the distance from the indium tin oxide layer 101 to the second carrier transport layer 104 is 598 nm or less.

[0051] The counter electrode layer 105 collects the conduction electrons extracted by the second carrier transport layer 104. The counter electrode layer 105 is in contact with the indium tin oxide layer 101 at the groove structure P3. Materials that can be used as the main component of the counter electrode layer 105 include, for example, carrier metals such as gold, alloys, silver nanowires, and carbon nanotubes.

[0052] (Method of manufacturing a grooved transparent electrode and a solar cell element) Next, the method for manufacturing the grooved transparent electrode and the organic solar cell element according to this embodiment will be described in detail with reference to the drawings. In the following description, Figures 1 and 2 will be referred to as appropriate.

[0053] FIG. 3 is a flowchart showing a method for manufacturing a solar cell element according to the first embodiment. In the method for manufacturing a solar cell element according to this embodiment, first, a P1 scribe is formed (step ST101). In other words, in the method for manufacturing a solar cell element according to this embodiment, a groove structure P1 is formed on transparent electrode 1 first.

[0054] That is, step ST101 according to this embodiment corresponds to the method for manufacturing a grooved transparent electrode according to this embodiment. Step ST101 according to this embodiment will be described in more detail below.

[0055] Fig. 4 is a cross-sectional view illustrating the method for manufacturing a solar cell element according to the first embodiment. More specifically, Fig. 4 is a cross-sectional view of the transparent electrode 1 taken along a plane perpendicular to the main surface of the transparent electrode 1 immediately before step ST101 is performed.

[0056] Immediately before step ST101 is performed, the transparent electrode 1 has a uniform indium tin oxide layer 101 provided on the surface of the transparent substrate 100. As the transparent electrode 1 shown in Fig. 4, for example, a commercially available ITO glass substrate can be used.

[0057] In step ST101, a groove structure P1 is formed by irradiating laser light onto the indium tin oxide layer 101 provided on the transparent substrate 100. More specifically, in step ST101, the laser light is irradiated onto the indium tin oxide layer 101 from the positive direction of the z-axis, while being scanned in the positive direction of the y-axis. Through these steps, the indium tin oxide layer 101 provided on the transparent substrate 100 is removed linearly to form the groove structure P1. That is, through these steps, the grooved transparent electrode 1 shown in FIG. 1 is formed.

[0058] In this way, in the method for manufacturing a grooved transparent electrode according to this embodiment, the groove structure P1 is formed by irradiating with laser light. Therefore, the method for manufacturing a solar cell element according to this embodiment can reduce manufacturing costs compared to when the groove structure P1 is formed using, for example, a wet edging method or the like.

[0059] Indium tin oxide, which is the main component of the indium tin oxide layer 101, has a lower melting point than other transparent electrode materials such as fluorine-doped tin oxide (FTO, F-doped tin oxide).For this reason, the transparent electrode 1 having the indium tin oxide layer 101 is more likely to develop burrs when irradiated with laser light than transparent electrodes using other transparent electrode materials.

[0060] Fig. 5 is a cross-sectional view showing the structure of a transparent electrode 1 on which burrs have occurred. As shown in Fig. 5, when the indium tin oxide layer 101 is irradiated with laser light, burrs 113 are likely to occur at the edges of the groove structure P1.

[0061] Fig. 6 is a cross-sectional view showing the structure of a solar cell element 10 using a transparent electrode 1 having burrs. In the solar cell element 10 shown in Fig. 6, the burrs 113 are in contact with the second carrier transport layer 104 at point S. That is, in the solar cell element 10 shown in Fig. 6, the indium tin oxide layer 101 and the second carrier transport layer 104 are short-circuited. In such a case, the shunt resistance of the solar cell element 10 increases, resulting in a decrease in the photoelectric conversion efficiency of the solar cell element 10.

[0062] Therefore, in step ST101, the irradiation energy density of the irradiated laser light is limited to a predetermined value or less to suppress the generation of burrs. That is, in the method for manufacturing a grooved transparent electrode according to this embodiment, the laser light is irradiated under mild conditions to suppress the generation of burrs at the edge of the groove structure P1.

[0063] Detailed experimental results will be described later. However, after extensive investigation, the inventors of the present application have determined that the irradiation energy density of the laser beam irradiated onto the indium tin oxide layer 101 is 1.9×10 -1 J / mm 2 It has been found that the height of the burrs in the groove structure P1 can be suppressed by the following. More specifically, the inventors of the present application set the irradiation energy density of the laser light to 1.9 × 10 -1 J / mm2 It was found that the height of the burrs can be suppressed to about 400 nm by setting the following.

[0064] The irradiation energy density of the laser light referred to here is specifically a physical quantity expressed by the following formula (2). E=P / (v s ×d s )...Equation (2) however, E is the irradiation energy density (J / mm 2 ) and P is the laser power (W), v s is the scanning speed (mm / s), d s is the spot diameter (mm).

[0065] Furthermore, the inventors of the present application have set the irradiation energy density of the laser light irradiated onto the indium tin oxide layer 101 to 1.3×10 -1 J / mm 2 It was found that the height of the burrs can be suppressed to about 200 nm by setting the following. Here, if the height of the burrs is suppressed to about 200 nm, even if the transparent electrode 1 is applied to a product that is easily affected by burrs, such as a thin-film solar cell, the burrs are unlikely to have a negative impact on the performance of the product. In other words, after careful consideration, the inventors of the present application have found an upper limit for the irradiation energy density of laser light that can suppress the height of burrs to a level that does not adversely affect the performance of the product to which the transparent electrode 1 is applied.

[0066] Furthermore, the inventors of the present application have set the irradiation energy density of the laser light irradiated onto the indium tin oxide layer 101 to 3.8×10 -2 J / mm 2 It has been found that the groove structure P1 can be appropriately processed by the above-mentioned method. That is, the inventors of the present application have found the lower limit of the irradiation energy density of the laser beam that can process the groove structure P1.

[0067] In this embodiment, the wavelength of the laser light irradiated onto the indium tin oxide layer 101 is not particularly limited, and may be determined based on the thickness of the indium tin oxide layer 101, for example. In this embodiment, the spot diameter of the laser light irradiated onto the indium tin oxide layer 101 is preferably 0.0005 to 0.04 mm, the scanning speed is preferably 200 to 400 mm / s, and the intensity is preferably 0.3 to 1.5 W.

[0068] Furthermore, the inventors of the present application have found that even when irradiating with laser light at the above-mentioned irradiation energy density, the groove structure P1 can be formed by a single laser irradiation as long as the depth of the groove structure is 200 nm or less. Therefore, the indium tin oxide layer 101 according to this embodiment preferably has a thickness of 200 nm or less. However, even if the depth of the groove structure is 200 nm or more, the groove structure P1 can be formed by irradiating the laser light multiple times.

[0069] Returning to the explanation of Figure 3. Next, a first carrier transport layer is formed (step ST102). The method for forming the first carrier transport layer 102 is not particularly limited, but may be, for example, an inkjet method, a spray coating method, a die coating method, a spin coating method, or a vacuum deposition method.

[0070] However, as described above, in the method for manufacturing a solar cell element according to this embodiment, the size of burrs generated in the transparent electrode 1 is reduced. Therefore, the method for manufacturing a solar cell element according to this embodiment is particularly effective when forming a film using a method such as an inkjet method, a spray coating method, a die coating method, or a spin coating method, which may cause liquid unevenness due to burrs. Therefore, the first carrier transport layer in the solar cell element according to this embodiment is preferably a hole transport layer containing an organic compound suitable for film formation by a method such as an inkjet method, a spray coating method, a die coating method, or a spin coating method.

[0071] Next, a photoelectric conversion layer is formed (step ST103). The method for forming the photoelectric conversion layer 103 is not particularly limited, but for example, an inkjet method, a spray coating method, a die coating method, a spin coating method, a vacuum deposition method, etc. can be used.

[0072] As described above, the method for manufacturing a solar cell element according to this embodiment is particularly effective when the distance from the indium tin oxide layer 101 to the second carrier transport layer 104 is 184 nm or more and 598 nm or less. Therefore, in steps ST102 and ST103, it is preferable to deposit the first carrier transport layer 102 and the photoelectric conversion layer 103 so that the total film thickness is 184 nm or more and 598 nm or less.

[0073] In addition, when the first carrier transport layer 102 and the photoelectric conversion layer 103 are formed using a film formation method using a solution, such as an inkjet method, a spray coating method, a die coating method, or a spin coating method, the film thickness of these layers can be adjusted, for example, by adjusting the concentration of the solution or the amount of the solution applied.

[0074] Next, a second carrier transport layer is formed (step ST104). The method for forming the second carrier transport layer 104 is not particularly limited, but may be, for example, an inkjet method, a spray coating method, a die coating method, a spin coating method, or a vacuum deposition method.

[0075] Fig. 7 is a cross-sectional view illustrating the method for manufacturing the solar cell element according to the first embodiment. More specifically, Fig. 7 is a cross-sectional view of the solar cell element 10 immediately after step ST104 is completed, cut along a plane perpendicular to the main surface of the solar cell element 10. In the solar cell element 10 shown in Figure 7, a first carrier transport layer 102, a photoelectric conversion layer 103, and a second carrier transport layer 104 are stacked on the surface of a transparent electrode 1 in the order shown, and each layer exists as a uniform layer without being divided.

[0076] Next, a P2 scribe is formed (step ST105). Fig. 8 is a cross-sectional view illustrating the method for manufacturing the solar cell element according to the first embodiment. More specifically, Fig. 8 is a cross-sectional view of the solar cell element 10 immediately after step ST105 is completed, cut along a plane perpendicular to the main surface of the solar cell element 10.

[0077] As shown in FIG. 8, immediately after step ST105 is completed, P2 scribes, that is, groove structures P2 are formed in the solar cell element 10. The groove structure P2 is formed by removing linear portions parallel to the y-axis from the first carrier transport layer 102, the photoelectric conversion layer 103, and the second carrier transport layer 104. The groove structure P2 can be formed, for example, by irradiating the second carrier transport layer 104 with laser light and scanning the laser light parallel to the y-axis. The first carrier transport layer 102, the photoelectric conversion layer 103, and the second carrier transport layer 104 are divided into a plurality of regions via a groove structure P2, and each region is electrically insulated.

[0078] Next, a counter electrode is formed (step ST106). The method for forming the counter electrode is not particularly limited, but when the counter electrode layer 105 is a metal film, for example, a vacuum deposition method can be used. When the counter electrode layer 105 is made of silver nanowires or carbon nanotubes, for example, an inkjet method, a spray coating method, a die coating method, a spin coating method, etc. can be used.

[0079] 9 is a cross-sectional view illustrating the method for manufacturing the solar cell element according to the first embodiment. More specifically, FIG. 9 is a cross-sectional view of the solar cell element 10 immediately after step ST106 is completed, cut along a plane perpendicular to the main surface of the solar cell element 10. As shown in FIG. 9, immediately after step ST106 is completed, the groove structure P2 is filled with the counter electrode layer 105 in the solar cell element 10. As shown in FIG.

[0080] Finally, the method for manufacturing the solar cell element according to this embodiment is completed by forming a P3 scribe (step ST107). Upon completion of step ST107, the solar cell element 10 is in the state shown in FIG. As shown in FIG. 2, immediately after step ST107 is completed, P3 scribe, that is, groove structure P3 is formed in solar cell element 10.

[0081] The groove structure P3 is formed by removing a linear portion of the counter electrode layer 105 shown in Fig. 9 that is parallel to the y-axis. The groove structure P3 can be formed, for example, by irradiating the counter electrode layer 105 with a laser beam and scanning the laser beam parallel to the y-axis. By forming the groove structures P1 and P3 in this way, the solar cell element 10 according to this embodiment becomes an integrated solar cell, and the output voltage can be improved.

[0082] As described above, in the method for manufacturing a grooved transparent electrode according to this embodiment, the indium tin oxide layer 101 provided on the transparent substrate 100 is irradiated with an energy density of 1.9×10 -1 J / mm 2 The method includes the step of forming a groove structure P1 by irradiating the following laser light. The method for manufacturing a solar cell element according to this embodiment includes the steps of depositing a first carrier transport layer 102, a photoelectric conversion layer 103, a second carrier transport layer 104, and a counter electrode layer 105 on the surface of the grooved transparent electrode 1 manufactured using the above-described method for manufacturing a grooved transparent electrode, and also includes the steps of forming groove structures P2 and P3.

[0083] With this configuration, the method for manufacturing a grooved transparent electrode according to this embodiment can reduce the height of burrs and also reduce manufacturing costs. Furthermore, with this configuration, the method for manufacturing a solar cell element according to this embodiment can improve the photoelectric conversion efficiency of the solar cell element. [Example]

[0084] Hereinafter, the method for manufacturing a grooved transparent electrode according to the present disclosure will be described in more detail using examples, but the method for manufacturing a grooved transparent electrode according to the present disclosure is not limited to the following examples.

[0085] <Creating a grooved transparent electrode> Example 1 Laser light intensity: 0.3 W, scanning speed: 200 mm / s, spot diameter: 0.04 mm (irradiation energy density: 3.8 × 10 -2 J / mm 2 ) ITO glass (thickness of indium tin oxide layer: 150 nm) manufactured by Geomatec Co., Ltd. was irradiated with UV laser light to create a transparent electrode with grooves. Example 2 A grooved transparent electrode was fabricated by irradiating UV laser light under the same conditions as in Example 1, except that the laser light intensity was set to 0.375 W (irradiation energy density: 4.69 × 10 -2 J / mm 2 ). Example 3 A grooved transparent electrode was fabricated by irradiating UV laser light under the same conditions as in Example 1, except that the laser light intensity was set to 0.5 W (irradiation energy density: 6.3 × 10 -2 J / mm 2 ). Example 4 A grooved transparent electrode was fabricated by irradiating UV laser light under the same conditions as in Example 1, except that the laser light intensity was set to 1.0 W (irradiation energy density: 1.3 × 10 -1 J / mm 2 ). Example 5 A grooved transparent electrode was fabricated by irradiating UV laser light under the same conditions as in Example 1, except that the laser light intensity was set to 1.5 W (irradiation energy density: 1.9 × 10 -1 J / mm 2 ). (Comparative Example 1) A grooved transparent electrode was fabricated by irradiating UV laser light under the same conditions as in Example 1, except that the laser light intensity was set to 2.0 W (irradiation energy density: 2.5×10 -1 J / mm 2 ). (Comparative Example 2) A grooved transparent electrode was fabricated by irradiating UV laser light under the same conditions as in Example 1, except that the laser light intensity was set to 0.275 W (irradiation energy density: 3.44 × 10 -2 J / mm 2 ).

[0086] <Burri height measurement> Using a white light interferometer measuring device manufactured by Keyence Corporation, the height of the burrs generated on the grooved transparent electrodes produced in Examples 1 to 5 and Comparative Example 1 was measured. The measurement results are shown in FIG.

[0087] FIG. 10 is a graph showing the relationship between the laser light intensity and the height of the burrs. As shown in Figure 10, 2.5 × 10 -1 J / mm 2 In Comparative Example 1, in which the laser beam was irradiated at an irradiation energy density of 1.9×10, a burr of 598 nm was generated. -1 J / mm 2 When attention is focused on Example 5 in which the laser beam was irradiated at an irradiation energy density of 100 nm, it can be seen that the height of the burrs was suppressed to 409 nm.

[0088] Furthermore, in Examples 1 to 4, the burr height was suppressed to less than 200 nm. -1 J / mm 2 In Example 4, in which the laser beam was irradiated at an irradiation energy density of 184 nm, the height of the burrs was 184 nm.

[0089] Furthermore, 3.8 x 10 -2 J / mm 2 From the results of Example 1, in which the laser beam was irradiated at an irradiation energy density of at least 3.8 × 10 -2 J / mm 2 If the above value is satisfied, it is possible to form a groove structure on the transparent electrode surface. -2 J / mm 2 In Comparative Example 2, in which the laser beam was irradiated at an irradiation energy density of 1000 kJ / cm, the groove structure P1 could not be formed.

[0090] From the above results, in the method for producing a grooved transparent electrode according to the present disclosure, the irradiation energy density of the irradiated laser light is 1.9 × 10 -1 J / mm 2 It is sufficient if it is less than 3.8 × 10 -2 J / mm 2 Over 1.3 x 10 -1 J / mm 2 It is found to be particularly preferred that: Furthermore, the above results show that the method for manufacturing a grooved transparent electrode according to the present disclosure is particularly effective when applied to the manufacture of a solar cell element in which the distance from the indium tin oxide layer to the second carrier transport layer is 184 nm or more and 598 nm or less.

[0091] <Observation of the appearance of the grooved transparent electrode> Fig. 11 is a top view of a solar cell with grooves according to an example and a comparative example, traced from a micrograph of the solar cell with grooves according to the example and the comparative example. More specifically, Fig. 11(a) is a top view of a solar cell with grooves according to an example 4, traced from a micrograph of the transparent electrode with grooves prepared in the comparative example 1, and Fig. 11(b) is a top view of a solar cell with grooves according to an example 4, traced from a micrograph of the transparent electrode with grooves prepared in the comparative example 1. As is clear from a comparison of Fig. 11(a) and Fig. 11(b), the irradiation energy density of the laser beam is 2.5 × 10 -1 J / mm 2 In Comparative Example 1, the linearity of the groove structure P1 deteriorated. The above results also show that the method for manufacturing a grooved transparent electrode according to this embodiment contributes to maintaining the linearity of the groove structure P1.

[0092] <Formation of hole transport layer> Example 6 The PEDOT:PSS solution was spin-coated onto the grooved transparent electrode prepared in Example 4, and then dried by heating at 140° C. for 10 minutes. (Comparative Example 3) Using the grooved transparent electrode prepared in Comparative Example 1, a hole transport layer was formed in the same manner as in Example 6.

[0093] <Observation of the appearance of the hole transport layer> The upper surfaces of the hole transport layers prepared in Example 6 and Comparative Example 3 were observed using a microscope. FIG. 12 is a top view obtained by tracing photographs of the hole transport layers according to the example and the comparative example. More specifically, Figure 12(a) is a top view of a hole transport layer prepared in Example 6, traced from a micrograph, and Figure 12(b) is a top view of a hole transport layer prepared in Comparative Example 3, traced from a micrograph. Looking at Figure 12(b), 2.5 × 10 -1 J / mm 2 In the hole transport layer (Comparative Example 3) formed on the transparent electrode irradiated with laser light at an irradiation energy density of 1000 u / s, traces of splashes of liquid remained. On the other hand, Fig. 12(a) shows that 1.3 × 10 -1 J / mm 2 In the hole transport layer (Example 4) formed on the transparent electrode irradiated with laser light at an irradiation energy density of 1000 .mu.m, no traces of liquid splashing during coating remained, and a uniform hole transport layer was obtained. The above results also demonstrate that the method for manufacturing a solar cell element according to this embodiment contributes to the film-forming properties of the hole transport layer.

[0094] <Creating solar cell elements> Example 7 On the hole transport layer formed in Example 6, (Cs a1 MA a2 FA a3 A DMF / DMSO mixed solution of a ternary cation-based perovskite compound of PbI3 was spin-coated, left to stand, and then heated and dried. A solution of PCBM and BCP was then spin-coated, left to stand, and then dried. A silver electrode was then vapor-deposited to produce a solar cell element. In the above formula, MA is a methylammonium cation, FA is a formamidinium cation, and a1, a2, and a3 are real numbers that satisfy a1+a2+a3=1. Comparative Example 4 A solar cell element was produced in the same manner as in Example 7, except that the hole transport layer formed in Comparative Example 3 was used.

[0095] <Shunt resistance measurement> The shunt resistance of the solar cell elements produced in Example 7 and Comparative Example 3 was measured using a Keithley source meter. As a result, the shunt resistance of the solar cell element produced in Example 7 was 2.3 × 10 6 Ω, and the shunt resistance of the solar cell element prepared in Comparative Example 3 was 4.3 × 10 2 It was Omega. From the above results, it is clear that the solar cell element manufactured using the method for manufacturing a solar cell element according to this embodiment has superior performance compared to the comparative example.

[0096] <Other embodiments> Although the manufacturing method of the solar cell element according to the first embodiment is applied to a solar cell element having a photoelectric conversion layer, the application of the manufacturing method of the solar cell element according to the present disclosure is not limited to this. For example, the manufacturing method of the solar cell element according to the present disclosure may be applied to a thin-film solar cell in which an n-type semiconductor layer and a p-type semiconductor layer are directly bonded, such as a silicon solar cell.

[0097] The present disclosure is not limited to the above-described embodiment, and can be modified as appropriate within the scope of the present disclosure. [Explanation of symbols]

[0098] 1 transparent electrode 10 Solar cell element 100 transparent substrate 101 Indium Tin Oxide layer 102 First carrier transport layer 103 Photoelectric conversion layer 104 Second Carrier Transport Layer 105 Counter electrode layer P1, P2, P3 groove structure

Claims

1. For an indium tin oxide layer provided on a transparent substrate, the irradiation energy density was 1.9 × 10 －１ J / mm ２ The method includes a step of forming a groove structure by irradiating a laser beam as follows: A method for manufacturing a grooved transparent electrode.

2. The irradiation energy density of the laser light is 3.8×10 －２ J / mm ２ That's all. The method for producing the grooved transparent electrode according to claim 1 .

3. The irradiation energy density of the laser light is 1.3×10 －１ J / mm ２ Below is the The method for producing the grooved transparent electrode according to claim 1 or 2.

4. The depth of the groove structure is 200 nm or less. The method for producing the grooved transparent electrode according to claim 1 or 2.

5. For an indium tin oxide layer provided on a transparent substrate, the irradiation energy density was 1.9 × 10 －１ J / mm ２ forming a groove structure by irradiating the substrate with a laser beam as follows; forming a first carrier transport layer; and forming a second carrier transport layer. A method for manufacturing a solar cell element.

6. a distance from the indium tin oxide layer to the second carrier transport layer is 184 nm or more; The method for manufacturing a solar cell element according to claim 5 .

7. the distance from the indium tin oxide layer to the second carrier transport layer is 598 nm or less; The method for manufacturing a solar cell element according to claim 6 .

8. the first carrier transport layer is a hole transport layer containing an organic compound; The method for manufacturing a solar cell element according to claim 5 .

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