Solar cell module manufacturing method and solar cell module

Abstract

To provide a see-through solar cell module with high visibility.SOLUTION: A solar cell module manufacturing method according to an embodiment of the present invention includes the steps of laminating a first transparent electrode layer on a transparent substrate, forming a first separation groove extending in a first direction by irradiating with a laser, laminating a first semiconductor layer, a photoelectric conversion layer, and a second semiconductor layer, forming a second separation groove extending in the first direction by irradiating with a laser, laminating a second transparent electrode layer, forming a third separation groove extending in the first direction by irradiating with a laser, and removing the layer and lifting off layers laminated on the first layer by irradiating with a laser having a wavelength such that the optical absorption coefficient of the portion of the first transparent electrode layer on the first semiconductor layer side or at least the portion of the first semiconductor layer in contact with the first transparent electrode layer is greater than the optical absorption coefficient of the photoelectric conversion layer, thereby forming a light-transmitting groove extending in a second direction intersecting the first direction.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present invention relates to a method for manufacturing a solar cell module and a solar cell module. [Background technology]

[0002] Solar cell modules are known that are formed by electrically connecting multiple solar cell subcells in series on a single transparent substrate. By modularizing solar cells, the effective area decreases because there is an ineffective area between the subcells, but it is possible to reduce resistance loss, especially in the electrodes on the light-receiving surface side. If solar cells are properly modularized, the improvement in photoelectric conversion efficiency due to the reduction in resistance loss outweighs the reduction in effective area.

[0003] The solar cell module can be manufactured by a method of forming a plurality of solar cell subcells electrically connected in series by sequentially performing the steps of stacking a first transparent electrode layer on a transparent substrate, cutting the first transparent electrode layer by irradiating with a first laser, stacking a first semiconductor layer, a photoelectric conversion layer, and a second semiconductor layer, cutting the first semiconductor layer, the photoelectric conversion layer, and the second semiconductor layer by irradiating with a second laser, stacking a second transparent electrode layer, and cutting the first semiconductor layer, the photoelectric conversion layer, the second semiconductor layer, and the second transparent electrode layer by irradiating with a third laser, and gradually shifting the positions of the first laser irradiation, the second laser irradiation, and the third laser irradiation in that order.

[0004] Furthermore, it has been proposed that such a solar cell module be made see-through by irradiating the laser in multiple lines extending in a direction perpendicular to the first to third lasers, and removing (ablating) the first semiconductor layer, the photoelectric conversion layer, the second semiconductor layer, and the second transparent electrode layer to form multiple light-transmitting grooves, thereby imparting optical transparency and allowing the view on the opposite side of the solar cell module to be seen (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2014-078767 Summary of the Invention [Problem to be solved by the invention]

[0006] When removing the photoelectric conversion layer by laser irradiation, it is necessary to use a laser with a wavelength absorbed by the photoelectric conversion layer. However, the laser absorption rate of the first semiconductor layer is insufficient, and the first semiconductor layer is likely to remain. As a result, in conventional see-through solar cells, the remaining first semiconductor layer absorbs and diffuses light, which can make the image viewed through the solar cell unclear. Furthermore, when forming light-transmitting grooves by laser irradiation, the material in the area adjacent to the light-transmitting grooves in the photoelectric conversion layer discolors due to heat, reducing visibility. Therefore, an object of the present invention is to provide a see-through solar cell module with high visibility. [Means for solving the problem]

[0007] A solar cell module manufacturing method according to one aspect of the present invention includes the steps of: laminating a first transparent electrode layer on a first side of a sheet-like transparent base material; removing the first transparent electrode layer by laser irradiation to form a first separation groove extending in a first direction; laminating a first semiconductor layer, a photoelectric conversion layer, and a second semiconductor layer on the first side of the first transparent electrode layer; removing the first semiconductor layer, the photoelectric conversion layer, and the second semiconductor layer by laser irradiation to form a second separation groove extending in the first direction adjacent to the first separation groove; laminating a second transparent electrode layer on the second semiconductor layer; and removing at least the second transparent electrode layer from the first semiconductor layer, the photoelectric conversion layer, the second semiconductor layer, and the second transparent electrode layer by laser irradiation. and forming a light-transmitting groove extending in a second direction intersecting the first direction by removing the first semiconductor layer side portion of the first transparent electrode layer or at least the portion of the first semiconductor layer in contact with the first transparent electrode layer by irradiating with a laser having a wavelength such that the optical absorption coefficient of the first semiconductor layer side portion of the first transparent electrode layer or at least the portion of the first semiconductor layer in contact with the first transparent electrode layer is larger than the optical absorption coefficient of the photoelectric conversion layer, thereby removing the first semiconductor layer side portion of the first transparent electrode layer or at least the portion of the first semiconductor layer in contact with the first transparent electrode layer and lifting off a layer stacked on the first side of the first semiconductor layer side portion of the first transparent electrode layer or at least the portion of the first semiconductor layer in contact with the first transparent electrode layer.

[0008] In the above-described method for manufacturing a solar cell module, the first semiconductor layer may include a NiOx layer in contact with the first transparent electrode layer, and an infrared laser may be used in the step of forming the light-transmitting grooves.

[0009] In the above-described solar cell module manufacturing method, in the step of forming the light-transmitting grooves, the laser may be irradiated onto the first semiconductor layer through the transparent base material and the first transparent electrode layer.

[0010] A solar cell module according to one embodiment of the present invention comprises a sheet-like transparent substrate, a first transparent electrode layer, a first semiconductor layer, a photoelectric conversion layer, a second semiconductor layer, and a second transparent electrode layer, in this order, and has a first separation groove extending in a first direction and formed to cut the first transparent electrode layer, a second separation groove extending in the first direction close to the first separation groove and formed to cut the first semiconductor layer, the photoelectric conversion layer, and the second semiconductor layer, a third separation groove extending in the first direction close to the second separation groove and formed to cut at least the second transparent electrode layer out of the first semiconductor layer, the photoelectric conversion layer, the second semiconductor layer, and the second transparent electrode layer, and a light-transmitting groove extending in a second direction intersecting the first direction and formed to remove the first semiconductor layer, the photoelectric conversion layer, the second semiconductor layer, and the second transparent electrode layer. [Effects of the Invention]

[0011] According to the present invention, a see-through solar cell module having high visibility can be provided. [Brief explanation of the drawings]

[0012] [Figure 1] FIG. 2 is a schematic rear view of the solar cell module according to one embodiment of the present invention. [Figure 2] 2 is a schematic cross-sectional view of the solar cell module of FIG. 1 taken along line XX. [Figure 3] 2 is a schematic cross-sectional view of the solar cell module of FIG. 1 taken along line YY. [Figure 4] 1 is a flowchart showing the steps of a solar cell module manufacturing method according to one embodiment of the present invention. [Figure 5] 5 is a schematic cross-sectional view showing a light-transmitting groove forming step in the solar cell module manufacturing method of FIG. 4. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0013] Hereinafter, embodiments of the present invention will be described with reference to the drawings. Fig. 1 is a schematic rear view of a solar cell module 1 according to one embodiment of the present invention. Fig. 2 is a schematic cross-sectional view of the solar cell module 1 of Fig. 1 taken along line XX, and Fig. 3 is a schematic cross-sectional view of the solar cell module of Fig. 1 taken along line YY. In the figures, the dimensions of each component have been modified for clarity. In particular, the thickness of each layer in the figures is enlarged for clarity.

[0014] The solar cell module 1 comprises a sheet-shaped (plate-shaped or film-shaped) transparent substrate 11, a first transparent electrode layer 12 laminated on a first side (lower side in Figure 2) of the transparent substrate 11, a first semiconductor layer 13 laminated on the first side of the first transparent electrode layer 12, a photoelectric conversion layer 14 laminated on the first side of the first semiconductor layer 13, a second semiconductor layer 15 laminated on the first side of the photoelectric conversion layer 14, and a second transparent electrode layer 16 laminated on the first side of the second semiconductor layer 15.

[0015] The solar cell module 1 is divided into a plurality of sub-cell units 2, each formed in a strip shape extending in a first direction and arranged side by side in a second direction intersecting the first direction, and a pair of connection units 3, arranged on both sides of the plurality of sub-cell units 2 in the second direction. Each of the sub-cell units 2 is an area that independently performs photoelectric conversion. The connection unit 3 is an area that does not contribute to photoelectric conversion and to which wiring is connected for outputting power from the plurality of sub-cell units 2 to the outside. Note that a larger module (solar cell panel) may be formed using a plurality of solar cell modules 1. In other words, the solar cell module 1 may be used as a solar cell sub-module.

[0016] The solar cell module 1 also has a plurality of first separation grooves 21 extending in a first direction and formed to cut the first transparent electrode layer 12, a plurality of second separation grooves 22 extending in the first direction close to each of the first separation grooves 21 and formed to cut the first semiconductor layer 13, the photoelectric conversion layer 14, and the second semiconductor layer 15, a plurality of third separation grooves 23 extending in the first direction close to each of the second separation grooves 22 and formed to cut at least the second transparent electrode layer 16 out of the first semiconductor layer 13, the photoelectric conversion layer 14, the second semiconductor layer 15, and the second transparent electrode layer 16, and a light-transmitting groove 31 extending in the second direction and formed to cut the first semiconductor layer 13, the photoelectric conversion layer 14, the second semiconductor layer 15, and the second transparent electrode layer 16.

[0017] The transparent base material 11 is a structural member that supports the other layers 12, 13, 14, 15, and 16 and ensures the strength of the solar cell module 1 as a whole.

[0018] The first transparent electrode layer 12 collects the first charges generated in the photoelectric conversion layer 14 through the first semiconductor layer 13 and outputs them to the adjacent subcell unit 2 or the connection unit 3. In this embodiment, the first transparent electrode layer 12 is a positive electrode that collects holes.

[0019] The first semiconductor layer 13 is a layer that passes charges (photocarriers) of a first polarity generated in the photoelectric conversion layer 14, and in this embodiment is a hole transport layer (HTL) that transports holes to the first transparent electrode layer 12. The first semiconductor layer 13 may have a multilayer structure. Furthermore, the first semiconductor layer 13 or a part thereof may be called a charge transport layer, a passivation layer, a buffer layer, etc. depending on its function, and the term "semiconductor layer" in this specification is a concept that encompasses such layers.

[0020] The photoelectric conversion layer 14 performs photoelectric conversion by absorbing incident light and generating photocarriers (electrons and holes). In the present invention, the photoelectric conversion layer 14 can be formed from a relatively unstable material among materials capable of performing photoelectric conversion, and in this embodiment, it is intended that the photoelectric conversion layer 14 be formed from a material mainly composed of a perovskite compound.

[0021] The second semiconductor layer 15 is a layer that passes charges of the second polarity generated in the photoelectric conversion layer 14. In this embodiment, it is an electron transport layer (ETL) that transfers electrons to the second transparent electrode layer 16. Like the first semiconductor layer 13, the second semiconductor layer 15 may have a multilayer structure, and may be called a charge transport layer, a passivation layer, a buffer layer, or the like.

[0022] The second transparent electrode layer 16 is an electrode that forms a pair with the first transparent electrode layer 12. In this embodiment, the second transparent electrode layer 16 is a negative electrode that collects electrons.

[0023] The first separation groove 21, the second separation groove 22, and the third separation groove 23 define a plurality of sub-cell units 2 and a pair of connection units 3 that are electrically connected in series. The light-transmitting groove 31 is formed to transmit light and enable the opposite side to be viewed through the solar cell module 1. The light-transmitting groove 31 divides each sub-cell unit 2 into a plurality of units, but does not divide the first transparent electrode layer 12. Therefore, each sub-cell unit 2 is electrically composed of a plurality of photoelectric conversion elements connected in parallel by the first transparent electrode layer 12.

[0024] Such a solar cell module 1 can be manufactured by a solar cell module manufacturing method according to one embodiment of the present invention shown in Fig. 4. The solar cell module manufacturing method of this embodiment includes a step of laminating a first transparent electrode layer 12 on a transparent substrate 11 (S01: first transparent electrode layer laminating step), a step of forming first separation grooves 21 by removing first transparent electrode layer 12 by laser irradiation (S02: first separation groove forming step), a step of laminating a first semiconductor layer 13 on first transparent electrode layer 12 (S03: first semiconductor layer laminating step), a step of laminating a photoelectric conversion layer 14 on first semiconductor layer 13 (S4: photoelectric conversion layer laminating step), a step of laminating a second semiconductor layer 15 on photoelectric conversion layer 14 (S5: second semiconductor layer laminating step), and a step of laminating first semiconductor layer 13, photoelectric conversion layer 14, and second semiconductor layer 15 by laser irradiation. The method includes a step of forming a second separation groove 22 by removing the first semiconductor layer 13, the photoelectric conversion layer 14, the second semiconductor layer 15, and the second transparent electrode layer 16 (S06: second separation groove forming step), a step of stacking a second transparent electrode layer 16 on the second semiconductor layer 15 (S07: second transparent electrode layer stacking step), a step of forming a third separation groove 23 by removing at least the second transparent electrode layer 16 of the first semiconductor layer 13, the photoelectric conversion layer 14, the second semiconductor layer 15, and the second transparent electrode layer 16 by irradiating with a laser (S08: third separation groove forming step), and a step of forming a light-transmitting groove 31 by removing the first semiconductor layer 13, the photoelectric conversion layer 14, the second semiconductor layer 15, and the second transparent electrode layer 16 by irradiating with a laser (S09: light-transmitting groove forming step).

[0025] In the first transparent electrode layer lamination step S01, the first transparent electrode layer 12 is laminated on one main surface of the transparent substrate 11. The first transparent electrode layer 12 can be laminated on the transparent substrate 11 by a method such as sputtering or vacuum deposition.

[0026] A glass plate is typically used as the transparent substrate 11, but a resin sheet such as polyimide, polyamide, polyethylene terephthalate, etc. may also be used to impart flexibility to the solar cell module 1, or a composite material such as laminated glass may also be used.

[0027] The first transparent electrode layer 12 may be formed of a transparent conductive oxide (TCO) that is conductive and optically transparent. Examples of the transparent conductive oxide that can be used to form the first transparent electrode layer 12 include indium oxide, tin oxide, zinc oxide, titanium oxide, and composite oxides thereof. Among these, indium-based composite oxides containing indium oxide as the main component are preferred. Indium oxide is particularly preferred from the viewpoints of high conductivity and transparency. Furthermore, it is preferable to add a dopant to indium oxide to ensure reliability or higher conductivity. Examples of dopants include Sn, W, Zn, Ti, Ce, Zr, Mo, Al, Ga, Ge, As, Si, and S. A particularly suitable example is indium tin oxide (ITO), which is indium oxide doped with tin.

[0028] The lower limit of the thickness of the first transparent electrode layer 12 is preferably 5 nm, more preferably 10 nm. Meanwhile, the upper limit of the thickness of the first transparent electrode layer 12 is preferably 200 nm, more preferably 150 nm. By making the thickness of the first transparent electrode layer 12 equal to or greater than the lower limit, electrical resistance can be reduced, thereby improving photoelectric conversion efficiency. Furthermore, by making the thickness of the first transparent electrode layer 12 equal to or less than the upper limit, the amount of light incident on the photoelectric conversion layer 14 can be increased, thereby improving photoelectric conversion efficiency. The first transparent electrode layer 12 may have a multilayer structure, such as a laminated structure of a polycrystalline ITO layer and an amorphous ITO layer. Furthermore, the first transparent electrode layer 12 may have a thin layer on the side of the first semiconductor layer 13, formed of, for example, FTO (F-doped tin oxide), which improves the bonding strength with the first semiconductor layer 13 or the charge transfer efficiency.

[0029] In the first separation groove forming step S02, the first transparent electrode layer 12 is removed in the form of multiple parallel lines in a planar view by laser ablation, thereby forming the first separation grooves 21. The laser used for irradiation may be, for example, an SHG laser (second harmonic of a YAG laser). The intensity of the laser used to form the first separation grooves 21 is set so that the first transparent electrode layer 12 can be reliably insulated between the sub-cell portions 2 and so that damage to the transparent substrate 11 can be minimized. In order to reduce damage to the transparent substrate 11, it is preferable to irradiate the laser directly onto the first transparent electrode layer 12 without passing through the transparent substrate 11.

[0030] Considering that the first separation groove 21 is formed by laser ablation, the width of the first separation groove 21 is preferably 10 μm or more and 200 μm or less, and more preferably 20 μm or more and 100 μm or less, which makes it possible to reliably separate the sub-cell portions 2 and ensure the effective area of ​​the sub-cell portions 2.

[0031] In the first semiconductor layer lamination step S03, the first semiconductor layer 13 is laminated on the first transparent electrode layer 12. The first semiconductor layer 13 can be formed by a method such as sputtering or vacuum deposition. When the first semiconductor layer 13 contains an organic substance, the first semiconductor layer 13 can be formed by a method such as coating and drying a solution of the organic substance.

[0032] Examples of the main material of the first semiconductor layer 13, which is a hole transport layer, include metal oxides such as NiOx and CuOx, and organic materials such as PTAA (Poly(bis(4-phenyl)(2,4,6-trimethylphenyl)amine)) and Spiro-MeOTAD. The first semiconductor layer 13 may also be a self-assembled monolayer (SAM) formed of, for example, 2PACz ([2-(9H-Carbazol-9-yl)ethyl]phosphonic Acid), MeO-2PACz ([2-(3,6-Dimethoxy-9H-carbazol-9-yl)ethyl]phosphonic Acid), Me-4PACz ([4-(3,6-Dimethyl-9H-carbazol-9-yl)butyl]phosphonic Acid), or the like. The first semiconductor layer 13 may be a laminate of these materials, but preferably includes a NiOx layer 131 in contact with the first transparent electrode layer 12 so that it can be easily removed when forming the light-transmitting grooves 31. In the illustrated embodiment, the first semiconductor layer 13 has a NiOx layer 131 in contact with the first transparent electrode layer 12, and a SAM layer 132 made of an organic self-assembled monolayer in contact with the first semiconductor layer 13.

[0033] The thickness of the first semiconductor layer 13 can vary greatly depending on the material, the configuration of adjacent layers, and the like, but the lower limit of the thickness of the first semiconductor layer 13 is preferably 0.5 nm, more preferably 1 nm. On the other hand, the upper limit of the thickness of the first semiconductor layer 13 is preferably 200 nm, more preferably 100 nm. By setting the thickness of the first semiconductor layer 13 to be equal to or greater than the lower limit, the photoelectric conversion layer 14, the second semiconductor layer 15, and the second transparent electrode layer 16 can be reliably laser lifted off to form the light-transmitting grooves 31. Furthermore, by setting the thickness of the first semiconductor layer 13 to be equal to or less than the upper limit, it is possible to prevent a decrease in photoelectric conversion efficiency due to a decrease in electrical resistance and an unnecessary increase in energy consumption in the light-transmitting groove formation process.

[0034] In the photoelectric conversion layer lamination step of S04, a photoelectric conversion layer 14 is laminated on the first semiconductor layer 13. The thickness of the photoelectric conversion layer 14 depends on the forming material, etc., but is preferably 100 nm or more and 1000 nm or less in order to increase the light absorption rate while reducing the travel distance of the generated charges.

[0035] The perovskite compound contained in the photoelectric conversion layer 14 may be a compound represented by the formula ABX3, which includes an organic atomic group A containing at least one of a monovalent organic ammonium ion and an amidinium ion; a metal atom B that generates a divalent metal ion; and a halogen atom X containing at least one of an iodide ion I, a bromide ion Br, a chloride ion Cl, and a fluoride ion F. Examples of the organic atomic group A include methylammonium MA (CH3NH3) and formamidinium FA (CH3N2). Examples of the metal atom B include lead Pb and tin Sn, with lead being the main component. Examples of the halogen atom X include at least one of iodide I, bromide Br, and chloride Cl. Substitution of part or all of the organic atomic group A with an alkali metal Am has also been investigated, and such perovskite compounds are not excluded from the present invention. Examples of the alkali metal Am include potassium K, cesium Cs, and rubidium Rb.

[0036] Specifically, preferred perovskite compounds include methylammonium lead halides (MAPbX3) such as MAPbI3, MAPbBr3, and MAPbCl3, and formamidinium lead halides (FAPbX3) such as FAPbI3, FAPbBr3, and FAPbCl3. Note that the halogen atom X may contain multiple types, and FA compounds containing both methylammonium and formamidinium as the organic atomic group A are also suitable. y MA 1-y PbX3. When the alkali metal Am is contained, Am y FA z MA 1-y-z PbIX, Am y FA 1-yPbIX, etc. Am may be a single species of Cs, Rb, or K, or may contain multiple species (where y and z are any positive integers).

[0037] When the perovskite compound is methylammonium lead halide (MAPbX3(CH3NH3PbX3)), the photoelectric conversion layer 14 can be formed by sequentially depositing a lead halide (PbX2) material and a methylammonium halide (MAX) material, and reacting the thin films of these materials at a reaction temperature. For example, when the perovskite compound is methylammonium lead iodide (MAPbI y X (3-y) (CH3NH3PbI y X (3-y) In the case of the above, the photoelectric conversion layer 14 is formed by sequentially depositing a lead halide (PbX2) material and a methylammonium iodide (MAI) material, and then reacting the resulting thin films at a reaction temperature. The photoelectric conversion layer 14 can also be formed by a sol-gel method in which a perovskite compound is synthesized in a liquid-phase coating, or a coating method in which a solution containing a pre-synthesized perovskite compound is applied.

[0038] In the second semiconductor layer lamination step S05, the second semiconductor layer 15 is laminated on the photoelectric conversion layer 14. The second semiconductor layer 15, which is an electron transport layer, can be primarily made of, for example, fullerene and its derivatives. Examples of fullerene and its derivatives include C60, C70, and their hydrides, oxides, metal complexes, and derivatives with alkyl groups added thereto, such as PCBM ([6,6]-Phenyl-C61-Butyric Acid Methyl Ester). In particular, forming the second semiconductor layer 15 from a material containing fullerene encapsulating lithium (Li) can improve electron transport efficiency. The second semiconductor layer 15 may also be formed from a metal oxide such as tin oxide (SnO2) or zinc oxide (ZnO), and may have a multilayer structure. The second semiconductor layer 15 can be formed by a method such as a sol-gel method, a coating method, a vacuum deposition method, a sputtering method, or an atomic layer deposition method, depending on the material. The thickness of the second semiconductor layer 15 can vary greatly depending on the material, the configuration of the adjacent layers, etc., but can be, for example, 3 nm or more and 50 nm or less.

[0039] In the second separation groove forming step S06, the first semiconductor layer 13, the photoelectric conversion layer 14, and the second semiconductor layer 15 are removed in a plurality of parallel lines by laser ablation, thereby forming a plurality of second separation grooves 22. The laser used has a wavelength that is absorbed by the photoelectric conversion layer 14, and may be, for example, an SHG laser (second harmonic of a YAG laser). The width of the second separation groove 22 may be the same as that of the first separation groove 21, but may be larger than that of the first separation groove 21 to ensure connection of the second transparent electrode layer 16 to the first transparent electrode layer 12. In the second separation groove forming step, too, it is preferable to irradiate the laser from the second semiconductor layer 15 side so that the laser is incident only on the first semiconductor layer 13, the photoelectric conversion layer 14, and the second semiconductor layer 15 to be removed.

[0040] In the second transparent electrode layer lamination step S07, a second transparent electrode layer 16 is laminated on the second semiconductor layer 15. The second transparent electrode layer 16 is a paired electrode with the first transparent electrode layer 12 and serves as a negative electrode in this embodiment. The second transparent electrode layer 16 is laminated so as to contact the first transparent electrode layer 12 at the back of the second separation groove 22 to electrically connect adjacent subcell units 2 in series. The second transparent electrode layer 16 may include a metal layer made of, for example, copper to reduce electrical resistance. The second transparent electrode layer 16 may also have a multilayer structure including a transparent conductive oxide layer to improve adhesion to the second semiconductor layer 15. The second transparent electrode layer 16 can be laminated by a method such as sputtering, vacuum deposition, or plating. The lower limit of the thickness of the second transparent electrode layer 16 is preferably 10 nm, more preferably 20 nm. The upper limit of the thickness of the second transparent electrode layer 16 is preferably 200 nm, more preferably 100 nm. By setting the thickness of the second transparent electrode layer 16 to the above lower limit or more, the current collection resistance can be sufficiently reduced. Furthermore, by setting the thickness of the second transparent electrode layer 16 to the above upper limit or less, the third separation groove 23 can be easily formed.

[0041] In the third separation groove forming step S08, at least the second transparent electrode layer 16 (in the illustrated embodiment, all of these layers) of the first semiconductor layer 13, photoelectric conversion layer 14, second semiconductor layer 15, and second transparent electrode layer 16 is removed by laser ablation in a plurality of parallel lines, thereby forming a plurality of third separation grooves 22. As with the first separation grooves 21, an SHG laser (second harmonic of a YAG laser) or the like can be used as the laser to be applied. The width of the third separation grooves 23 can be the same as that of the first separation grooves 21. In the third separation groove forming step as well, it is preferable to apply the laser from the second transparent electrode layer 16 side so that the laser is incident only on the layer to be removed.

[0042] In the light-transmitting groove formation process S09, a laser having a wavelength such that the optical absorption coefficient of the first semiconductor layer 13 is greater than the optical absorption coefficient of the photoelectric conversion layer 14 is irradiated so as to be focused on the portion of the first transparent electrode layer 12 facing the first semiconductor layer 13 (e.g., the FTO thin layer) or at least the portion of the first semiconductor layer 13 that is in contact with the first transparent electrode layer 12 (e.g., the NiOx layer 131 in this embodiment), thereby removing the portion of the first transparent electrode layer 12 facing the first semiconductor layer 13 or at least the portion of the first semiconductor layer 13 that is in contact with the first transparent electrode layer 12, and lifting off layers (e.g., the SAM layer 132, photoelectric conversion layer 14, second semiconductor layer 15 and second transparent electrode layer 16 in this embodiment) stacked on the first side of the portion of the first transparent electrode layer 12 facing the first semiconductor layer 13 or at least the portion of the first semiconductor layer 13 that is in contact with the first transparent electrode layer 12 (the layer irradiated with the laser). That is, the layer on which the laser is focused (typically the first semiconductor layer 13) is removed by laser ablation, which involves evaporation or decomposition due to the heat of the laser, but the layers stacked on top of the layer on which the laser is focused (typically the photoelectric conversion layer 14, the second semiconductor layer 15, and the second transparent electrode layer 16) are fractured due to the disappearance of the first semiconductor layer 13 that supports them directly below, even without the direct application of heat. A suitable laser for use in the light-transmitting groove formation step is an infrared laser, which reduces the absorption coefficient of the photoelectric conversion layer 14, which is mainly made of a perovskite compound, and increases the absorption coefficient of the first semiconductor layer 13, particularly the NiOx layer 131. In this way, by using a laser with a wavelength that transmits through the photoelectric conversion layer 14 and is absorbed by the first semiconductor layer 13, sufficient thermal energy can be applied to the photoelectric conversion layer 14, ensuring reliable removal of the photoelectric conversion layer 14. Furthermore, by removing the photoelectric conversion layer 14 by laser lift-off, it is possible to prevent the photoelectric conversion layer 14 near the formed light-transmitting grooves 31 from being altered (discolored) by heat, even without excessively strict process control. Furthermore, in the light-transmitting groove forming step, in order to prevent the photoelectric conversion layer 14 from being overheated, it is preferable to irradiate the first semiconductor layer 13 with laser L through the transparent substrate 11 and the first transparent electrode layer 12, as shown in FIG.

[0043] As described above, the solar cell module 1, which is formed so as not to leave the first semiconductor layer 13 at the bottom of the light-transmitting groove 31 and not to alter the photoelectric conversion layer 14 near the light-transmitting groove 31, has high photoelectric conversion efficiency and excellent visibility when viewing the scenery on the other side through the solar cell module 1.

[0044] Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments and various modifications and variations are possible. For example, the solar cell module manufacturing method according to the present invention may include a step of stacking additional layers, such as an anti-reflection film or a protective film. Furthermore, two or more layers, namely, the first semiconductor layer, the photoelectric conversion layer, and the second semiconductor layer, may be simultaneously formed using a layer-separating solution. [Explanation of symbols]

[0045] 1. Solar cell module 2 Subcell section 3 Connection 11 Transparent base material 12 First transparent electrode layer 13 First semiconductor layer 131 NiOx layer 132 SAM layer 14 Photoelectric conversion layer 15 Second semiconductor layer 16 Second transparent electrode layer 21 1st separation groove 22 2nd separation groove 23 Third separation groove 31 Translucent groove

Claims

1. laminating a first transparent electrode layer on a first side of a sheet-like transparent substrate; removing the first transparent electrode layer by irradiating it with a laser to form a first separation groove extending in a first direction; laminating a first semiconductor layer, a photoelectric conversion layer, and a second semiconductor layer on the first side of the first transparent electrode layer; forming a second separation trench extending in the first direction adjacent to the first separation trench by removing the first semiconductor layer, the photoelectric conversion layer, and the second semiconductor layer by irradiating with a laser; laminating a second transparent electrode layer on the second semiconductor layer; forming a third separation groove extending in the first direction adjacent to the second separation groove by removing at least the second transparent electrode layer among the first semiconductor layer, the photoelectric conversion layer, the second semiconductor layer, and the second transparent electrode layer by irradiating with a laser; a step of forming a light-transmitting groove extending in a second direction intersecting the first direction by removing the first semiconductor layer side portion of the first transparent electrode layer or at least the portion of the first semiconductor layer in contact with the first transparent electrode layer and lifting off a layer stacked on the first side of the first semiconductor layer side portion of the first transparent electrode layer or at least the portion of the first semiconductor layer in contact with the first transparent electrode layer by irradiating a laser having a wavelength such that the light absorption coefficient of the first semiconductor layer side portion of the first transparent electrode layer or at least the portion of the first semiconductor layer in contact with the first transparent electrode layer is larger than the light absorption coefficient of the photoelectric conversion layer; A solar cell module manufacturing method comprising:

2. 2. The method for manufacturing a solar cell module according to claim 1, wherein the first semiconductor layer includes a NiOx layer in contact with the first transparent electrode layer, and an infrared laser is used in the step of forming the light-transmitting grooves.

3. 3. The solar cell module manufacturing method according to claim 1, wherein in the step of forming the light-transmitting grooves, the laser is irradiated onto the first semiconductor layer through the transparent base material and the first transparent electrode layer.

4. a sheet-like transparent substrate, a first transparent electrode layer, a first semiconductor layer, a photoelectric conversion layer, a second semiconductor layer, and a second transparent electrode layer, in this order; a first separation groove extending in a first direction and formed to cut the first transparent electrode layer; a second separation trench extending in the first direction adjacent to the first separation trench and formed to cut the first semiconductor layer, the photoelectric conversion layer, and the second semiconductor layer; a third separation trench extending in the first direction adjacent to the second separation trench and formed to cut at least the second transparent electrode layer among the first semiconductor layer, the photoelectric conversion layer, the second semiconductor layer, and the second transparent electrode layer; a light-transmitting groove extending in a second direction intersecting the first direction and formed to remove the first semiconductor layer, the photoelectric conversion layer, the second semiconductor layer, and the second transparent electrode layer; A solar cell module having:

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