Solar cell and method for manufacturing solar cell

Abstract

The present invention provides: a solar cell in which water is prevented from entering a photoelectric conversion layer, and in which any deterioration in the characteristics of the photoelectric conversion layer is suppressed; and a method for manufacturing the solar cell. Provided is a solar cell (10) having a layered configuration in which a support (12), a support-side electrode (14), an electron transport layer (15), a photoelectric conversion layer (16), a hole transport layer (17), a sealing-layer-side electrode (18), an inorganic adhesive layer (20), and a sealing layer (22) are laminated in the stated order, wherein: the photoelectric conversion layer (16) contains a perovskite compound; the inorganic adhesive layer (20) is configured from compound containing one of an oxide and a nitride containing one element from among Si and Al; and in the inorganic adhesive layer (20), a region in which the atomic ratio for the compound is a second ratio lower than a first ratio is present between a first contact surface (20a) where the inorganic adhesive layer (20) is in contact with the sealing layer (22) and a second contact surface (20b) where the inorganic adhesive layer (20) is in contact with the sealing-layer-side electrode (18) in the thickness direction of the inorganic adhesive layer (20), where the first ratio is the atomic ratio of the elements contained in the compound to the oxygen or nitrogen contained in the compound at the first contact surface (20a) and the second contact surface (20b) in the thickness direction of the inorganic adhesive layer (20).

Description

Solar cell and method for manufacturing solar cell

[0001] The present invention relates to a solar cell in which a photoelectric conversion layer contains a perovskite compound and a method for manufacturing the solar cell, and in particular to a solar cell sealed using an inorganic adhesive layer and a sealing layer and a method for manufacturing the solar cell.

[0002] Currently, there are perovskite solar cells that use perovskite compounds in the photoelectric conversion layer. It is known that the performance of perovskite solar cells deteriorates when exposed to moisture. For this reason, perovskite solar cells are sealed to prevent water from penetrating into the photoelectric conversion layer.

[0003] For example, Patent Document 1 proposes a solar cell that includes a support, a solar cell element provided on the support, an adhesive layer covering the solar cell element, and a sealant layer covering the adhesive layer, the solar cell element including an electrode, a photoelectric conversion layer including a perovskite compound, and a back electrode, in that order, the sealant layer including a main body portion covering the adhesive layer and an edge region connected to the main body portion, and the average density of the edge region is 1.01 to 2 times the average density of the main body portion.

[0004] Japanese Patent Application Laid-Open No. 2023-042617

[0005] The solar cell of Patent Document 1 has an adhesive layer made of a cured acrylic resin or epoxy resin, etc. Such adhesive layers made of a cured acrylic resin or epoxy resin are prone to voids, which can allow water to penetrate from the side surfaces of the adhesive layer, resulting in an insufficient sealing effect and deterioration of the photoelectric conversion layer, i.e., the solar cell. An object of the present invention is to provide a solar cell and a method for manufacturing a solar cell that prevent water from penetrating the photoelectric conversion layer and suppress deterioration of the properties of the photoelectric conversion layer.

[0006] In order to achieve the above-mentioned object, invention [1] is a solar cell having a layer structure in which a support, a support-side electrode, an electron transport layer, a photoelectric conversion layer, a hole transport layer, a sealing layer-side electrode, an inorganic adhesive layer, and a sealing layer are stacked in this order, wherein the photoelectric conversion layer contains a perovskite compound, and the inorganic adhesive layer is composed of a compound containing one of an oxide and a nitride containing one of Si and Al, and in the thickness direction of the inorganic adhesive layer, the atomic ratio of the element contained in the compound to the oxygen or nitrogen contained in the compound at a first contact surface of the inorganic adhesive layer in contact with the sealing layer and a second contact surface of the inorganic adhesive layer in contact with the sealing layer-side electrode is a first ratio, and in the inorganic adhesive layer, there is a region between the first contact surface and the second contact surface in the thickness direction of the inorganic adhesive layer where the atomic ratio of the compound is a second ratio lower than the first ratio.

[0007] Invention [2] is a solar cell having a layer structure in which a conductive support, an electron transport layer, a photoelectric conversion layer, a hole transport layer, a sealing layer side electrode, an inorganic adhesive layer, and a sealing layer are stacked in this order, wherein the photoelectric conversion layer contains a perovskite compound, and the inorganic adhesive layer is composed of a compound containing one of an oxide and a nitride containing one of the elements Si and Al, and in the thickness direction of the inorganic adhesive layer, the atomic ratio of the element contained in the compound to the oxygen or nitrogen contained in the compound at a first contact surface of the inorganic adhesive layer in contact with the sealing layer and at a second contact surface of the inorganic adhesive layer in contact with the sealing layer side electrode is a first ratio, and in the inorganic adhesive layer, there is a region between the first contact surface and the second contact surface in the thickness direction of the inorganic adhesive layer where the atomic ratio of the compound is a second ratio lower than the first ratio.

[0008] Invention [3] is the solar cell according to Invention [1] or [2], wherein the inorganic adhesive layer has a thickness of 0.3 to 5 nm. Invention [4] is the solar cell according to any one of Inventions [1] to [3], wherein the atomic ratio of the compound is 1.0 to 3.0. Invention [5] is the solar cell according to any one of Inventions [1] to [4], wherein the region where the atomic ratio of the compound is the second ratio is located at the center in the thickness direction of the inorganic adhesive layer.

[0009] Invention [6] is a method for manufacturing a solar cell having a layer structure in which a support, a support-side electrode, an electron transport layer, a photoelectric conversion layer, a hole transport layer, a sealing layer-side electrode, an inorganic adhesive layer, and a sealing layer are laminated in this order, the method comprising: a first forming step of forming a first inorganic adhesive layer by a plasma CVD method on a surface of the sealing layer facing the sealing layer-side electrode, and forming a first laminate having the first inorganic adhesive layer on a surface of the sealing layer facing the sealing layer-side electrode; and a second forming step of forming a first laminate having the first inorganic adhesive layer on a surface of the sealing layer facing the sealing layer-side electrode by plasma CVD. The method for manufacturing a solar cell includes a second formation step of forming a second inorganic adhesive layer by Method D to form a second laminate having the second inorganic adhesive layer on the surface of the sealing layer side electrode of the laminated base material, and a third formation step of laminating the first inorganic adhesive layer of the first laminate and the second inorganic adhesive layer of the second laminate within 60 seconds after the formation of the first or second laminate, whichever is formed first, to form an inorganic adhesive layer, wherein the first inorganic adhesive layer and the second inorganic adhesive layer are composed of a compound containing one of an oxide and a nitride containing one of the elements Si and Al.

[0010] Invention [7] is a method for manufacturing a solar cell having a layer structure in which a conductive support, an electron transport layer, a photoelectric conversion layer, a hole transport layer, a sealing layer side electrode, an inorganic adhesive layer, and a sealing layer are laminated in this order, the method comprising: a first forming step of forming a first inorganic adhesive layer by a plasma CVD method on a surface of the sealing layer facing the sealing layer side electrode, and forming a first laminate having the first inorganic adhesive layer on the surface of the sealing layer facing the sealing layer side electrode; and a second forming step of forming a first laminate by a plasma CVD method on a surface of the sealing layer side electrode of a laminated base material in which the conductive support, the electron transport layer, the photoelectric conversion layer, the hole transport layer, and the sealing layer side electrode are laminated in this order. and a third formation step of laminating the first inorganic adhesive layer of the first laminate and the second inorganic adhesive layer of the second laminate within 60 seconds after the formation of the first or second laminate, whichever is formed first, to form an inorganic adhesive layer, wherein the first inorganic adhesive layer and the second inorganic adhesive layer are composed of a compound containing one of an oxide and a nitride containing one of Si and Al.

[0011] Invention [8] is the method for manufacturing a solar cell according to Invention [6] or [7], in which the first laminate and the second laminate are individual sheets, and the third forming step is carried out after the first forming step and the second forming step. Invention [9] is the method for manufacturing a solar cell according to Invention [6] or [7], in which the first forming step and the second forming step are carried out by roll-to-roll, and the third forming step is carried out after the first forming step and the second forming step. Invention

[10] is the method for manufacturing a solar cell according to any one of Inventions [6] to [9], in which the first inorganic adhesive layer and the second inorganic adhesive layer have the same thickness.

[0012] According to the present invention, it is possible to provide a solar cell that prevents water from entering the photoelectric conversion layer and suppresses deterioration of the characteristics of the photoelectric conversion layer, and a method for manufacturing the solar cell.

[0013] FIG. 1 is a schematic cross-sectional view showing a first example of a solar cell according to an embodiment of the present invention. FIG. 2 is a schematic enlarged view of a main part of the first example of a solar cell according to an embodiment of the present invention. FIG. 3 is a schematic cross-sectional view showing a second example of a solar cell according to an embodiment of the present invention. FIG. 4 is a schematic cross-sectional view showing one step of a manufacturing method for the first example of a solar cell according to an embodiment of the present invention. FIG. 5 is a schematic cross-sectional view showing one step of a manufacturing method for the first example of a solar cell according to an embodiment of the present invention. FIG. 6 is a schematic view showing an example of a roll-to-roll system apparatus used in manufacturing a solar cell according to an embodiment of the present invention.

[0014] The solar cell and the method for manufacturing the solar cell of the present invention will be described in detail below based on preferred embodiments shown in the accompanying drawings. Note that the drawings described below are merely illustrative for explaining the present invention, and the present invention is not limited to the drawings shown below. Note that the "to" symbol indicating a numerical range below includes the values ​​written on both sides. For example, when ε is between α and β, the range of ε includes α and β, and expressed in mathematical symbols, α≦ε≦β. Angles such as "angles expressed by specific numerical values," "parallel," and "orthogonal" include the error range generally accepted in the relevant technical field unless otherwise specified. Furthermore, temperatures include the error range generally accepted in the relevant technical field.

[0015] [First Example of Solar Cell] Fig. 1 is a schematic cross-sectional view showing a first example of a solar cell according to an embodiment of the present invention. Fig. 2 is a schematic enlarged view of a main portion of the first example of a solar cell according to an embodiment of the present invention. The solar cell 10 shown in Fig. 1 has a layer structure in which a support 12, a support-side electrode 14, an electron transport layer 15, a photoelectric conversion layer 16, a hole transport layer 17, a sealing layer-side electrode 18, an inorganic adhesive layer 20, and a sealing layer 22 are stacked in this order. The direction in which the support 12, the support-side electrode 14, the electron transport layer 15, the photoelectric conversion layer 16, the hole transport layer 17, the sealing layer-side electrode 18, the inorganic adhesive layer 20, and the sealing layer 22 are stacked is referred to as the stacking direction Ds.

[0016] The support 12 supports the support-side electrode 14, the electron transport layer 15, the photoelectric conversion layer 16, the hole transport layer 17, the sealing layer-side electrode 18, the inorganic adhesive layer 20, and the sealing layer 22. The support-side electrode 14 and the sealing layer-side electrode 18 are used to extract the electricity generated in the photoelectric conversion layer 16 to the outside. The electron transport layer 15, the photoelectric conversion layer 16, and the hole transport layer 17 constitute a photoelectric conversion section 24. Light incident on the solar cell 10 is photoelectrically converted in the photoelectric conversion layer 16. As described above, the support-side electrode 14 and the sealing layer-side electrode 18 extract the electricity generated by photoelectric conversion in the photoelectric conversion layer 16 to the outside.

[0017] The inorganic adhesive layer 20 adheres the sealing layer 22. The sealing layer 22 protects the photoelectric conversion layer 16 from water. Although not specifically shown, the inorganic adhesive layer 20 covers the periphery of the photoelectric conversion layer 16 and is also formed on the end faces in a direction perpendicular to the stacking direction of the photoelectric conversion layer 16. The support 12, the support-side electrode 14, the electron transport layer 15, the photoelectric conversion layer 16, the hole transport layer 17, the sealing layer-side electrode 18, the inorganic adhesive layer 20, and the sealing layer 22 will be described in detail later.

[0018] The inorganic adhesive layer 20 is composed of a compound containing one of oxides and nitrides containing one of the elements Si and Al. More specifically, the compound is silicon oxide (SiO), silicon nitride (SiN), aluminum oxide (AlO), and aluminum nitride (AlN). In the thickness direction Dt of the inorganic adhesive layer 20, the atomic ratio of the element contained in the compound at the first contact surface 20a of the inorganic adhesive layer 20 in contact with the sealing layer 22 and the second contact surface 20b of the inorganic adhesive layer 20 in contact with the sealing layer side electrode 18 is defined as a first ratio. In the inorganic adhesive layer 20, between the first contact surface 20a and the second contact surface 20b in the thickness direction Dt of the inorganic adhesive layer 20, there is a region 25 where the atomic ratio of the compound is lower than the first ratio. The thickness direction Dt of the inorganic adhesive layer 20 is a direction parallel to the stacking direction Ds. In the inorganic adhesive layer 20, when the compound is silicon oxide (SiO), the first ratio and the second ratio are O / Si (at %). When the compound is silicon nitride (SiN), the first ratio and the second ratio are N / Si (at %). When the compound is aluminum oxide (AlO), the first ratio and the second ratio are O / Al (at %). When the compound is aluminum nitride (AlN), the first ratio and the second ratio are N / Al (at %).

[0019] The first and second ratios, which are the atomic ratios of the elements contained in the compound of the inorganic adhesive layer 20 to the oxygen or nitrogen contained in the compound, can be calculated from the analysis results obtained by X-ray photoelectron spectroscopy using an XPS device (AXIS-ULTRA manufactured by Shimadzu Corporation) for the inorganic adhesive layer 20. For example, Si, Al, O, and N are measured at multiple locations at predetermined intervals along the thickness direction Dt of the inorganic adhesive layer 20 between the first contact surface 20a and the second contact surface 20b of the inorganic adhesive layer 20, and the atomic ratios are calculated from the measurement results of Si, Al, O, and N.

[0020] In the solar cell 10, the use of the inorganic adhesive layer 20 allows the sealing layer 22 to be provided with high adhesion. In addition, water infiltration from the side surfaces of the photoelectric conversion layer 16 is prevented, providing a sufficient sealing effect. This provides the solar cell 10 with high moisture and heat resistance. As described above, the inorganic adhesive layer 20 is composed of a compound containing one of oxides and nitrides containing one of the elements Si and Al. This allows for a higher sunlight transmittance than general-purpose adhesives used to seal solar cells, and a higher absorbance of the photoelectric conversion layer.

[0021] In the inorganic adhesive layer 20, the first ratio and the second ratio, which are atomic ratios between the element contained in the compound and the oxygen or nitrogen contained in the compound, are, for example, 1.0 to 3.0.

[0022] Furthermore, in the inorganic adhesive layer 20, the region 25 where the atomic ratio of the compound is the second ratio is preferably located at the center of the thickness direction Dt of the inorganic adhesive layer 20. As described above, when the region 25 where the atomic ratio of the compound is the second ratio is located at the center of the thickness direction Dt of the inorganic adhesive layer 20, for example, the bonding interface of the films constituting the inorganic adhesive layer 20 is located at the center. In this case, the film thicknesses of the films to be bonded are the same, and the surface roughness or surface film quality of each film is the same, so the surfaces of the films to be bonded easily blend with each other, and the adhesion strength is high. The center of the thickness direction Dt of the inorganic adhesive layer 20 is the length L along the thickness direction Dt from the first contact surface 20a to the region 25 as shown in FIG. １ and a length L along the thickness direction Dt from the second contact surface 20b to the region 25. ２ The above-mentioned length L １ and length L ２ is obtained by using a scanning electron microscope (SEM) to obtain a cross-sectional image of the inorganic adhesive layer 20 in the thickness direction Dt, and １ and length L ２ The average value of each of the 10 points is taken as the length L １ and length L ２ Let's say.

[0023] In the inorganic adhesive layer 20, the region 25 where the atomic ratio of the compound is the second ratio is, for example, a region located at the center of the thickness direction Dt of the inorganic adhesive layer 20, as shown in Figure 2. The region 25 where the second ratio is, for example, a planar region extending in a direction perpendicular to the thickness direction Dt. The region 25 where the second ratio is, is not limited to the planar shape shown in Figure 2, and may be, for example, a dot-like region.

[0024] Solar cell 10 may be configured such that, for example, sunlight Ls is irradiated from the surface 22a side of sealing layer 22, photoelectric conversion is performed in photoelectric conversion layer 16, and the resulting electricity is extracted to the outside from support-side electrode 14 and sealing layer-side electrode 18. Solar cell 10 may also be configured such that, for example, sunlight Ls is irradiated from the side of support 12 opposite support-side electrode 14, photoelectric conversion is performed in photoelectric conversion layer 16, and the resulting electricity is extracted to the outside from support-side electrode 14 and sealing layer-side electrode 18.

[0025] [Second Example of Solar Cell] Figure 3 is a schematic cross-sectional view showing a second example of a solar cell according to an embodiment of the present invention. In Figure 3, components identical to those in Figures 1 and 2 are designated by the same reference numerals, and detailed descriptions thereof will be omitted. The solar cell 11 shown in Figure 3 differs from the solar cell 10 shown in Figure 1 in that a conductive support 13 is used instead of the support 12 and the support-side electrode 14, but otherwise has the same configuration as the solar cell 10 shown in Figure 1. The solar cell 11 has a layer configuration in which the conductive support 13, the electron transport layer 15, the photoelectric conversion layer 16, the hole transport layer 17, the sealing layer-side electrode 18, the inorganic adhesive layer 20, and the sealing layer 22 are stacked in this order. The support-side electrode 14 shown in Figure 1 is absent, and the electron transport layer 15 is provided on the conductive support 13. In the solar cell 11, the photoelectric conversion layer 16 also contains a perovskite compound. In addition, the inorganic adhesive layer 20 has a region 25 (see Figure 2) between the first contact surface 20a and the second contact surface 20b in the thickness direction Dt of the inorganic adhesive layer 20, where the atomic ratio of the compound is a second ratio lower than the first ratio.

[0026] In solar cell 11, for example, sunlight Ls is irradiated from the surface 22a side of encapsulating layer 22, photoelectrically converted in photoelectric conversion layer 16, and the resulting electricity is extracted to the outside from conductive support 13 and encapsulating layer-side electrode 18. Solar cell 11 differs from solar cell 10 described above only in that conductive support 13 is used instead of support 12 and support-side electrode 14, and the same effects as solar cell 10 can be obtained. Solar cell 11 may also be configured, for example, to be irradiated from the opposite side of electron transport layer 15 of conductive support 13, photoelectrically converted in photoelectric conversion layer 16, and the resulting electricity is extracted to the outside from support-side electrode 14 and encapsulating layer-side electrode 18. Note that the light irradiated in solar cell 10 and solar cell 11 is not limited to sunlight Ls.

[0027] [Example of a Manufacturing Method for a Solar Cell] Figures 4 to 6 are schematic cross-sectional views each showing a step in a manufacturing method for a first example of a solar cell according to an embodiment of the present invention. In Figures 4 to 6, components identical to those in Figures 1 and 2 are designated by the same reference numerals, and detailed descriptions thereof will be omitted. A method for manufacturing the solar cell 10 shown in Figure 1 will now be described. First, a first inorganic adhesive layer 26 is formed on the surface 22b of the sealing layer 22 facing the sealing layer-side electrode 18 (see Figure 1) using plasma CVD (chemical vapor deposition). This forms a first laminate 30 having the first inorganic adhesive layer 26 on the surface 22b of the sealing layer 22 facing the sealing layer-side electrode 18 (first formation step). The first inorganic adhesive layer 26 constitutes the inorganic adhesive layer 20.

[0028] Next, a laminated substrate 27 is prepared, in which a support 12, a support-side electrode 14, an electron transport layer 15, a photoelectric conversion layer 16, a hole transport layer 17, and a sealing layer-side electrode 18 are laminated in this order, as shown in FIG. 5 . For example, the laminated substrate 27 can be formed as follows. For example, a support 12 is prepared, and the support-side electrode 14, the electron transport layer 15, the photoelectric conversion layer 16, the hole transport layer 17, and the sealing layer-side electrode 18 are formed in this order on the support 12 using a known method to obtain the laminated substrate 27. Next, a second inorganic adhesive layer 28 is formed on the surface 18a of the sealing layer-side electrode 18 of the laminated substrate 27 by plasma CVD, as shown in FIG. 6 , to form a second laminate 32 having the second inorganic adhesive layer 28 on the surface 18a of the sealing layer-side electrode 18 of the laminated substrate 27 (second formation step). In the second forming step of forming the second laminate 32 described above, the second inorganic adhesive layer 28 is formed to cover the periphery of the photoelectric conversion section 24 including the photoelectric conversion layer 16, and is also formed on the end faces in a direction perpendicular to the stacking direction of the photoelectric conversion layer 16. The second inorganic adhesive layer 28 constitutes the inorganic adhesive layer 20.

[0029] Next, the first inorganic adhesive layer 26 of the first laminate 30 and the second inorganic adhesive layer 28 of the second laminate 32 are laminated together within 60 seconds after the formation of the first laminate 30 or the second laminate 32, whichever is formed first, to form an inorganic adhesive layer (third formation step). In the third formation step of forming the inorganic adhesive layer described above, for example, the surface 26a of the first inorganic adhesive layer 26 of the first laminate 30 shown in Figure 4 and the surface 28a of the second inorganic adhesive layer 28 of the second laminate 32 shown in Figure 6 are arranged opposite each other, and the first inorganic adhesive layer 26 and the second inorganic adhesive layer 28 are laminated together. The first inorganic adhesive layer 26 and the second inorganic adhesive layer 28 are laminated together and heated to a predetermined temperature, and then, for example, using a pressure press, the first inorganic adhesive layer 26 and the second inorganic adhesive layer 28 are pressed together to form the inorganic adhesive layer 20 (see FIG. 1 ). This provides the solar cell 10 shown in FIG. 1 .

[0030] By laminating the first inorganic adhesive layer 26 and the second inorganic adhesive layer 28 within 60 seconds after the formation of the previously formed laminate, the first inorganic adhesive layer 26 and the second inorganic adhesive layer 28 are well adhered to each other. This allows the sealing layer 22 to be provided with high adhesion, prevents water from penetrating into the photoelectric conversion layer 16, and produces a solar cell in which deterioration of the characteristics of the photoelectric conversion layer 16 is suppressed. Note that, it is sufficient to laminate the first inorganic adhesive layer 26 and the second inorganic adhesive layer 28 within 60 seconds after the formation of the previously formed laminate, and the first inorganic adhesive layer 26 and the second inorganic adhesive layer 28 in a laminated state may be bonded together by applying pressure while heating to a predetermined temperature as described above even after the 60 seconds have elapsed. Temporary bonding is performed by laminating the first inorganic adhesive layer 26 and the second inorganic adhesive layer 28 together, and actual bonding is performed by heating and pressurizing the laminated first inorganic adhesive layer 26 and the second inorganic adhesive layer 28 to bond them together.

[0031] On the other hand, if the first inorganic adhesive layer 26 and the second inorganic adhesive layer 28 are laminated for more than 60 seconds after the formation of the previously formed laminate, the adhesion between the first inorganic adhesive layer 26 and the second inorganic adhesive layer 28 will be poor, and even if the laminated first inorganic adhesive layer 26 and the second inorganic adhesive layer 28 are heated and pressurized to be bonded as described above, the sealing layer 22 cannot be formed with high adhesion. As a result, water penetration into the photoelectric conversion layer 16 cannot be prevented, and the characteristics of the photoelectric conversion layer 16 will deteriorate. Note that the formation times by the plasma CVD method are predetermined depending on the thicknesses of the first laminate 30 and the second laminate 32. In the third step, "within 60 seconds after the formation of the previously formed laminate" refers to within 60 seconds after the shorter of the predetermined formation times by the plasma CVD method has elapsed.

[0032] The first inorganic adhesive layer 26 and the second inorganic adhesive layer 28 constitute the inorganic adhesive layer 20 (see FIG. 1 ). Therefore, the first inorganic adhesive layer 26 and the second inorganic adhesive layer 28 are composed of the compounds that constitute the inorganic adhesive layer 20 described above. The first inorganic adhesive layer 26 and the second inorganic adhesive layer 28 are formed by a known method using the plasma CVD method described above, depending on the compounds that constitute the first inorganic adhesive layer 26 and the second inorganic adhesive layer 28. When a plasma irradiation device (not shown) that performs the plasma CVD method is used to form the first inorganic adhesive layer 26 and the second inorganic adhesive layer 28, the first inorganic adhesive layer 26 and the second inorganic adhesive layer 28 can be formed while the plasma irradiation device is fixed. Furthermore, when forming the first inorganic adhesive layer 26, the plasma irradiation device can be moved back and forth in a direction parallel to the surface 22 b of the sealing layer 22, which is the target of film formation, and the speed of the plasma irradiation device can be controlled so that each portion of the target of film formation is irradiated with plasma for the same period of time, thereby forming the first inorganic adhesive layer 26. Furthermore, when forming the second inorganic adhesive layer 28, the plasma irradiation device can be moved back and forth in a direction parallel to the surface 18 a of the sealing layer-side electrode 18, which is the target of film formation, and the speed of the plasma irradiation device can be controlled so that each portion of the target of film formation is irradiated with plasma for the same period of time, thereby forming the second inorganic adhesive layer 28, which is the target of film formation.

[0033] The thicknesses of the first inorganic adhesive layer 26 and the second inorganic adhesive layer 28 are appropriately determined depending on the thickness of the inorganic adhesive layer 20 to be formed. As described above, when the region 25 is located in the center of the inorganic adhesive layer 20, the first inorganic adhesive layer 26 and the second inorganic adhesive layer 28 are made to have the same thickness. The thickness of the first inorganic adhesive layer 26 and the thickness of the second inorganic adhesive layer 28 can each be set to a predetermined thickness by, for example, adjusting the formation time using a plasma CVD method. Furthermore, the first inorganic adhesive layer 26 and the second inorganic adhesive layer 28 have, for example, the same composition. This results in an inorganic adhesive layer 20 composed of a compound with a single composition. As described above, the inorganic adhesive layer 20 is composed of a compound containing one of oxides and nitrides containing one of the elements Si and Al. Having the same composition means that the combination of the elements Si and Al and the oxide and nitride is the same. More specifically, the first inorganic adhesive layer 26 and the second inorganic adhesive layer 28 are each composed of silicon oxide (SiO), silicon nitride (SiN), aluminum oxide (AlO), or aluminum nitride (AlN). Since the first inorganic adhesive layer 26 and the second inorganic adhesive layer 28 have the same composition, the surface roughness and surface film quality of the film are equivalent, and the surface 26 a of the first inorganic adhesive layer 26 and the surface 28 a of the second inorganic adhesive layer 28 are easily compatible with each other, which is preferable because the adhesion between the first inorganic adhesive layer 26 and the second inorganic adhesive layer 28 is high.

[0034] In the solar cell manufacturing method, for example, the first laminate 30 and the second laminate 32 are individual sheets, and the third step can be performed after the first forming step and the second forming step. A single sheet refers to a single sheet. In this case, the sealing layer 22 and the laminated base material 27 are each configured as a single sheet.

[0035] Alternatively, for example, the first and second forming steps may be performed by roll-to-roll, and the third step may be performed after the first and second forming steps. When the first and second forming steps are performed by roll-to-roll, an apparatus 40 shown in FIG. 7 may be used. The apparatus 40 includes, for example, a conveying shaft 41 around which the long sealing layer 22 is wound into a roll, a conveying roller 42 that conveys the sealing layer 22 delivered from the conveying shaft 41, a pair of rollers 46 that stack the first laminate 30 and the second laminate 32 (described below), and a take-up shaft 47 that winds up the laminate 34 formed by stacking the layers with the pair of rollers 46. Furthermore, a film-forming device 45 that forms a first inorganic adhesive layer 26 (see FIG. 4) on the surface 22b of the sealing layer 22 is provided between the conveying roller 42 and the pair of rollers 46. The laminated substrate 27 further includes, for example, a transport shaft 43 around which the long laminated substrate 27 is wound in a roll, and a transport roller 44 that transports the laminated substrate 27 sent out from the transport shaft 43. The laminated substrate 27 is transported to a pair of rollers 46 via the transport roller 44. A film forming device 48 that forms a second inorganic adhesive layer 28 (see FIG. 6) on a surface 18a (see FIG. 5) of the sealing layer side electrode 18 (see FIG. 5) of the laminated substrate 27 is provided between the transport roller 44 and the pair of rollers 46.

[0036] Both the film forming apparatus 45 and the film forming apparatus 48 are film forming apparatuses using a plasma CVD method and are performed in an atmospheric pressure atmosphere. As long as the first inorganic adhesive layer 26 and the second inorganic adhesive layer 28 can be formed using the plasma CVD method as described above, their configurations are not particularly limited. The film forming apparatus 45 forms the first inorganic adhesive layer 26 on the surface 22b of the sealing layer 22 to form the first laminate 30. The film forming apparatus 48 forms the second inorganic adhesive layer 28 on the surface 18a (see FIG. 5) of the sealing layer-side electrode 18 (see FIG. 5) of the laminated base material 27 to form the second laminate 32. At this time, the second inorganic adhesive layer 28 is also formed on the side surface of the photoelectric conversion unit 24 including the photoelectric conversion layer 16. Within 60 seconds after the formation of the first laminate, the first laminate 30 and the second laminate 32 are laminated by a pair of rollers 46 to obtain a laminate 34, and the laminate 34 is taken up in a roll on a take-up shaft 47. In other words, temporary bonding is performed within 60 seconds after the formation of the first laminate.

[0037] The roller pair 46 has two rollers 46a, 46b and has the function of changing the pressure between the two rollers 46a, 46b. The device 40 is provided with, for example, a motor (not shown) that rotates the conveying shaft 41, the conveying shaft 43, and the winding shaft 47, and a control unit (not shown) that controls the motor. This allows the conveying shaft 41 to feed the sealing layer 22, the conveying shaft 43 to feed the long laminate substrate 27, and the winding shaft 47 to wind the laminate 34, and also allows the timing of the above-mentioned feeding and winding to be adjusted. The laminate 34 wound around the winding shaft 47 is, for example, cut into a predetermined size, and the cut piece is heated while bonding the first inorganic adhesive layer 26 and the second inorganic adhesive layer 28 using a pressure press device to obtain the solar cell 10. That is, the first inorganic adhesive layer 26 and the second inorganic adhesive layer 28 are permanently bonded to obtain the solar cell 10. 7 , the path of the transport shaft 41, the transport roller 42, and the roller pair 46 is referred to as line P, and the path of the transport shaft 43, the transport roller 44, and the roller pair 46 is referred to as line Q. In the device 40, the transport speed of the sealing layer on line P and the transport speed of the laminated base material on line Q are adjusted in accordance with, for example, the plasma treatment time.

[0038] Here, when forming an inorganic film using the sputtering method, etching by ions progresses, which can deteriorate the photoelectric conversion layer and reduce the photoelectric conversion rate, but this does not occur with the plasma CVD method. Furthermore, when the above-mentioned first inorganic adhesive layer 26 and second inorganic adhesive layer 28 are formed using the sputtering method, the surface is dense, which results in poor adhesion between the first inorganic adhesive layer 26 and the second inorganic adhesive layer 28, and therefore a good inorganic adhesive layer cannot be obtained.

[0039] The manufacturing method for solar cell 10 has been described above, but solar cell 11 shown in FIG. 3 can also be manufactured using the same manufacturing method as solar cell 10. Solar cell 11 shown in FIG. 3 can be manufactured using the manufacturing method for solar cell 10 described above, except that the configuration of laminated substrate 27 shown in FIGS. 5 and 6 is different. Although not shown, laminated substrate 27 for solar cell 11 shown in FIG. 3 is configured using a conductive support 13 (see FIG. 3) instead of support 12 and support-side electrode 14 shown in FIG. 6. The order of the first step and the second step is not particularly limited, and either the first step or the second step may be performed first. The first step and the second step may also be performed in parallel, as in a roll-to-roll method.

[0040] Each component of the solar cell will be specifically described below. (Support) The support is not particularly limited as long as it can hold the solar cell consisting of each layer formed thereon, and can be selected appropriately depending on the purpose, for example, glass, plastic film, etc. When making a flexible solar cell, the support is preferably flexible, such as a plastic film. The flexibility described above is preferably such that the photoelectric conversion characteristics are not reduced even when the solar cell is deformed by handling, heating, cooling, etc. during or after production, and is preferably bendable to a curvature radius of 2 cm or less, and more preferably bendable to a curvature radius of 1 cm or less. Note that hereinafter, flexibility is as described above.

[0041] Examples of the material of the plastic film used for the support include thermoplastic resins such as polyester resin, methacrylic resin, resin composed of methacrylic acid-maleic acid copolymer, polystyrene resin, fluororesin, polyimide resin, fluorinated polyimide resin, polyamide resin, polyamideimide resin, polyetherimide resin, cellulose acylate resin, polyurethane resin, polyether ether ketone resin, polycarbonate resin, alicyclic polyolefin resin, polyarylate resin, polyethersulfone resin, polysulfone resin, resin composed of cycloolefin copolymer, fluorene ring-modified polycarbonate resin, alicyclic ring-modified polycarbonate resin, fluorene ring-modified polyester resin, and acryloyl compound.

[0042] The plastic film preferably has heat resistance. Specifically, the heat resistance preferably satisfies at least one of the physical properties of a glass transition temperature (Tg) of 100°C or higher and a linear thermal expansion coefficient of 40 ppm / K or lower. The Tg and linear expansion coefficient of the plastic film are measured by the method for measuring the transition temperature of plastics described in JIS (Japanese Industrial Standards)-K7121 and the test method for linear expansion coefficient by thermomechanical analysis of plastics described in JIS-K7197.

[0043] The Tg or linear expansion coefficient of the plastic film can be adjusted by additives, etc. Examples of such thermoplastic resins having excellent heat resistance include polyethylene naphthalate (PEN: 120°C (Tg, the same applies hereinafter)), polycarbonate (PC: 140°C), alicyclic polyolefins (for example, Zeonor 1600 (trade name), manufactured by Zeon Corporation: 160°C), polyarylate (PAr: 210°C), polyethersulfone (PES: 220°C), polysulfone (PSF: 190°C), and cycloolefins. Examples of suitable polycarbonates include fluorene ring-modified polycarbonates (BCF-PC: compounds described in JP-A-2000-227603: 225°C), alicyclic ring-modified polycarbonates (IP-PC: compounds described in JP-A-2000-227603: 205°C), acryloyl compounds (compounds described in JP-A-2002-80616: 300°C or higher), and polyimides. Of these, polyethylene naphthalate is preferred.

[0044] The support may be transparent to light. More specifically, the light transmittance for light in the wavelength range of 400 to 800 nm is preferably 80% or more, more preferably 85% or more, and even more preferably 90% or more. The light transmittance can be calculated by the method described in JIS-K7105, that is, by measuring the total light transmittance and the amount of scattered light using an integrating sphere light transmittance measuring device and subtracting the diffuse transmittance from the total light transmittance. The thickness of the support is not particularly limited, but is, for example, 1 to 800 μm, and preferably 10 to 300 μm.

[0045] (Conductive Support) The conductive support is not particularly limited as long as it is conductive and can support the solar cell composed of the layers formed thereon. The conductive support can be made of a conductive material, such as a metal or a conductive resin. For example, an aluminum substrate is used as the conductive support. Like the support, the conductive support may be transparent to light. More specifically, the light transmittance for light in the wavelength range of 400 to 800 nm is preferably 80% or more, more preferably 85% or more, and even more preferably 90% or more. The light transmittance is as described above. The thickness of the conductive support is not particularly limited, but like the support, it is, for example, 1 to 800 μm, preferably 10 to 300 μm.

[0046] (Support-side electrode) This electrode is used to extract the power generated in the photoelectric conversion layer. The material of the support-side electrode is not particularly limited, and examples thereof include metals, metal oxides, conductive polymers, and mixtures thereof. Among these, conductive polymers are preferred in terms of flexibility. Examples of metals include magnesium (Mg), aluminum (Al), calcium (Ca), titanium (Ti), chromium (Cr), manganese (Mn), iron (Fe), copper (Cu), zinc (Zn), strontium (Sr), silver (Ag), indium (In), tin (Sn), barium (Ba), bismuth (Bi), and alloys thereof. Examples of metal oxides include transparent conductive oxides (TCOs) such as tin oxide, fluorine-doped tin oxide (FTO), zinc oxide, antimony-doped zinc oxide (AZO), indium oxide, indium tin oxide (ITO), indium zinc oxide (IZO), and indium tungsten oxide (IWO).

[0047] The conductive polymer is not particularly limited as long as it is a polymer compound having conductivity, and the charge carriers to be transported may be either holes or electrons. Specific examples of conductive polymers include polythiophene, polypyrrole, polyaniline, polyphenylene vinylene, polyphenylene, polyacetylene, polyquinoxaline, polyoxadiazole, polybenzothiadiazole, etc., as well as polymer compounds having multiple conductive skeletons. Among these, polythiophene is preferred, and polyethylene dioxythiophene and polythienothiophene are particularly preferred. These polythiophenes are typically partially oxidized to achieve conductivity. The electrical conductivity of conductive polymers can be adjusted by the degree of partial oxidation (doping amount), with higher doping amounts resulting in higher electrical conductivity. Polythiophenes become cationic upon partial oxidation, requiring counter anions to neutralize the charge. An example of such a polythiophene is polyethylene dioxythiophene (PEDOT-PSS) with polystyrene sulfonic acid as the counter ion. As the conductive polymer, for example, the conductive polymer described in JP 2015-191916 A can be used. The support-side electrode is preferably transparent to light, like the support. More specifically, it preferably has a light transmittance of 80% or more for light in the wavelength range of 400 to 800 nm. The light transmittance is as described above. The film thickness of the support-side electrode is not particularly limited, and is preferably, for example, 0.01 to 30 μm. The layer structure of the support-side electrode is not particularly limited, and may be a single-layer structure, a laminated structure, or the like.

[0048] (Electron Transport Layer) The electron transport layer has the function of transporting electrons generated in the photoelectric conversion layer to the support-side electrode or the conductive support. The electron transport layer is formed of an electron transport material capable of transporting electrons. The electron transport material is not particularly limited, but an organic material (organic electron transport material) is preferred. Examples of organic electron transport materials include fullerene compounds such as [6,6]-phenyl-C61-butylic acid methyl ester (PC61BM), perylene compounds such as perylene tetracarboxylic diimide (PTCDI), and other low-molecular-weight compounds such as tetracyanoquinodimethane (TCNQ), or polymer compounds. The film thickness of the electron transport layer is not particularly limited, but is preferably 0.001 to 10 μm, and more preferably 0.01 to 1 μm.

[0049] (Photoelectric Conversion Layer) The photoelectric conversion layer has a photoelectric conversion function and obtains electricity from incident light. The photoelectric conversion layer contains a perovskite compound. The perovskite compound is a compound having a perovskite crystal structure. The compound having a perovskite crystal structure is not particularly limited. For example, the perovskite compounds described in International Publication No. 2019 / 053967, JP 2017-17166 A, and JP 2015-191916 A can be used in the photoelectric conversion layer. The method for forming the photoelectric conversion layer is not particularly limited, and examples include vacuum deposition, sputtering, gas phase reaction methods such as CVD, electrochemical deposition, and printing. In particular, by employing the printing method, solar cells can be easily formed over a large area. Examples of printing methods include spin coating and casting, and when using the printing method, a roll-to-roll method can be used. The thickness of the photoelectric conversion layer is not particularly limited, but is preferably, for example, 0.001 to 100 μm, more preferably 0.01 to 10 μm, and particularly preferably 0.01 to 5 μm.

[0050] (Hole Transport Layer) The hole transport layer has the function of replenishing electrons to the oxidant of the photoelectric conversion layer, and is preferably a solid layer (solid hole transport layer). The hole transport material forming the hole transport layer may be either a liquid material or a solid material, and is not particularly limited. Examples include inorganic materials such as CuI and CuNCS, and organic hole transport materials described in paragraphs 0209 to 0212 of JP 2001-291534 A. Preferred examples of the organic hole transport material include conductive polymers such as polythiophene, polyaniline, polypyrrole, and polysilane; spiro compounds in which two rings share a central atom having a tetrahedral structure such as C or Si; aromatic amine compounds such as triarylamine; triphenylene compounds; nitrogen-containing heterocyclic compounds; and liquid crystalline cyano compounds. The hole transport material is preferably an organic hole transport material that can be applied as a solution and becomes a solid, and specific examples thereof include 2,2',7,7'-tetrakis-(N,N-di-p-methoxyphenylamino)-9,9'-spirobifluorene (also referred to as spiro-MeOTAD), poly(3-hexylthiophene-2,5-diyl), 4-(diethylamino)benzaldehyde diphenylhydrazone, polyethylenedioxythiophene (PEDOT), etc. As the hole transport material for forming the hole transport layer, for example, the materials used for the hole transport layer described in WO 2019 / 053967, JP 2017-17166 A, and JP 2015-191916 A can be used. The thickness of the hole transport layer is not particularly limited, and is, for example, preferably 50 μm or less, more preferably 1 nm to 10 μm, even more preferably 5 nm to 5 μm, and particularly preferably 10 nm to 1 μm.

[0051] (Sealing layer-side electrode) The sealing layer-side electrode functions as a positive electrode in the solar cell. The sealing layer-side electrode is not particularly limited as long as it is conductive. The structure of the sealing layer-side electrode is preferably a structure with a high current collection effect. In order for light to reach the photoelectric conversion layer, at least one of the support or conductive support and the sealing layer-side electrode needs to be transparent to light. In a solar cell, when the support or conductive support is transparent to light and sunlight or the like is incident from the support or conductive support side, it is preferable that the sealing layer-side electrode has a property of reflecting light.

[0052] Examples of materials for forming the sealing layer-side electrode include metals such as platinum (Pt), gold (Au), nickel (Ni), copper (Cu), silver (Ag), indium (In), ruthenium (Ru), palladium (Pd), rhodium (Rh), iridium (Ir), osnium (Os), and aluminum (Al), the aforementioned conductive metal oxides, carbon materials, and conductive polymers. Carbon materials may be any conductive material formed by bonding carbon atoms, such as fullerene, carbon nanotubes, graphite, and graphene. The thickness of the sealing layer-side electrode is not particularly limited, but is preferably 0.01 to 100 μm, more preferably 0.01 to 10 μm, and particularly preferably 0.01 to 1 μm.

[0053] (Inorganic adhesive layer) This is provided between the sealing layer and the sealing layer-side electrode, and serves to adhere the sealing layer and fix the sealing layer to the sealing layer-side electrode. The compound constituting the inorganic adhesive layer is as described above. The inorganic adhesive layer preferably has an atomic ratio of the compound of 1.0 to 3.0. That is, the above-mentioned first ratio and second ratio are preferably 1.0 to 3.0. The region of the second ratio is preferably located at the center in the thickness direction of the inorganic adhesive layer. The center in the thickness direction of the inorganic adhesive layer is as described above. When the region of the second ratio is located at the center in the thickness direction of the inorganic adhesive layer, the adhesive strength of the inorganic adhesive layer is increased as described above. The position in the thickness direction of the inorganic adhesive layer of the region of the second ratio is, for example, located at the thickness D of the first inorganic adhesive layer 26. １ (see FIG. 4) and the thickness D of the second inorganic adhesive layer 28 ２ (See FIG. 6 ). The thickness D of the first inorganic adhesive layer 26 can be changed by adjusting the thickness D of the first inorganic adhesive layer 26. １ (see FIG. 4) and the thickness D of the second inorganic adhesive layer 28 ２ The thickness D of the first inorganic adhesive layer 26 (see FIG. 6) is adjusted by the formation time by the plasma CVD method. The inorganic adhesive layer preferably has a thickness of 0.3 to 5 nm, because this provides excellent moisture resistance, moist heat resistance, and adhesion of the inorganic adhesive layer. １ and the thickness D of the second inorganic adhesive layer 28 ２The thickness direction Dt of the first inorganic adhesive layer 26 and the second inorganic adhesive layer 28 is measured by using a scanning electron microscope. １ and the thickness D of the second inorganic adhesive layer 28 ２ The average value of each of the 10 points is determined as the thickness D of the first inorganic adhesive layer 26. １ and the thickness D of the second inorganic adhesive layer 28 ２ Let's say.

[0054] The inorganic adhesive layer is formed by a plasma CVD method. For example, when the compound constituting the inorganic adhesive layer is silicon oxide (SiO), it is formed by a plasma CVD method using tetraethoxysilane (TEOS). When the compound constituting the inorganic adhesive layer is silicon nitride (SiN), it is formed by a plasma CVD method using trisdimethylaminosilane. When the compound constituting the inorganic adhesive layer is aluminum oxide (AlO), it is formed by a plasma CVD method using trimethylaluminum. When the compound constituting the inorganic adhesive layer is aluminum nitride (AlN), it is formed by a plasma CVD method using trimethylamine. The inorganic adhesive layer is composed of a first inorganic adhesive layer and a second inorganic adhesive layer. The thickness of the inorganic adhesive layer is, for example, the thickness D of the first inorganic adhesive layer 26. １ (see FIG. 4) and the thickness D of the second inorganic adhesive layer 28 ２ (See Figure 6) and can be changed by adjusting the

[0055] (Sealing Layer) The sealing layer is intended to protect the solar cell. The sealing layer is provided to prevent substances that deteriorate the photoelectric conversion layer, such as water and oxygen, from penetrating into the photoelectric conversion layer. Examples of the sealing layer include a film of silicon or aluminum oxide, nitride, or nitride oxide formed on a PET (polyethylene terephthalate) film or a PEN film. The sealing layer may have a surface functional layer on the side opposite the photoelectric conversion layer, as needed. Examples of the surface functional layer include a matting agent layer, an anti-reflection layer, a hard coat layer, an anti-fogging layer, an anti-fouling layer, and an easy-adhesion layer. In addition, the surface functional layer is described in detail in JP 2006-289627 A.

[0056] (Other Configurations) The solar cell is not limited to the configuration described above, and may have, for example, a configuration having a blocking layer (not shown) and a porous layer (not shown) between the support-side electrode or the conductive support and the photoelectric conversion layer. In this case, the support-side electrode or the conductive support, the blocking layer, the porous layer, and the photoelectric conversion layer are stacked in this order.

[0057] (Blocking Layer) In a solar cell, for example, a reverse current occurs when the photoelectric conversion layer or the hole transport layer is electrically connected to the support-side electrode or the like. The blocking layer functions to prevent this reverse current. The blocking layer is also called a short-circuit prevention layer. The blocking layer can also function as a scaffold for supporting the photoelectric conversion layer.

[0058] The material forming the blocking layer is not particularly limited as long as it can fulfill the above-mentioned function. It is preferable that the material transmits light in the wavelength range of 400 to 800 nm and is insulating against the support-side electrode, the conductive support, and the like. Specifically, the "insulating material against the support-side electrode and the conductive support" refers to a compound (n-type semiconductor compound) whose conduction band energy level is equal to or higher than the conduction band energy level of the material forming the support-side electrode and the conductive support, and lower than the conduction band energy level of the material forming the porous layer and the ground state energy level of the material forming the photoelectric conversion layer. Examples of materials forming the blocking layer include silicon oxide, magnesium oxide, aluminum oxide, calcium carbonate, cesium carbonate, polyvinyl alcohol, and polyurethane. Materials commonly used in photoelectric conversion materials may also be used, such as titanium oxide, tin oxide, zinc oxide, niobium oxide, and tungsten oxide. Among these, titanium oxide, tin oxide, magnesium oxide, and aluminum oxide are preferred. The thickness of the blocking layer is not particularly limited, but is preferably 0.001 to 10 μm, more preferably 0.005 to 1 μm, and particularly preferably 0.01 to 0.1 μm.

[0059] (Porous Layer) The porous layer is provided between the blocking layer and the photoelectric conversion layer. The porous layer functions as a scaffold supporting the photoelectric conversion layer. In order to increase the light absorption efficiency of a solar cell, it is preferable to increase the surface area of ​​at least the portion that receives light such as sunlight, and it is also preferable to increase the overall surface area of ​​the porous layer.

[0060] The porous layer is preferably a microparticle layer having pores, in which microparticles of the material forming the porous layer are deposited or adhered to each other. The porous layer may also be a microparticle layer formed by depositing two or more types of microparticles. When the porous layer is a microparticle layer having pores, the amount of light absorber carried (adsorbed) can be increased. To increase the surface area of ​​the porous layer, it is preferable to increase the surface area of ​​each microparticle constituting the porous layer. When the microparticles forming the porous layer are coated on a support-side electrode, a conductive support, or the like, the surface area of ​​the microparticles is preferably 10 times or more, more preferably 100 times or more, the projected area. There is no particular upper limit, but it is usually about 5,000 times. The particle size of the microparticles forming the porous layer is preferably 0.001 to 1 μm as primary particles, in terms of the average particle size calculated by converting the projected area into the diameter of a circle. When the porous layer is formed using a dispersion of microparticles, the average particle size of the microparticles is preferably 0.01 to 100 μm as the average particle size of the dispersion.

[0061] The material constituting the porous layer is not particularly limited in terms of conductivity, and may be an insulator (insulating material), a conductive material, or a semiconductor (semiconductive material). Examples of materials that can be used to constitute the porous layer include metal chalcogenides (e.g., oxides, sulfides, selenides, etc.), compounds having a perovskite crystal structure (excluding perovskite compounds used as light absorbers), silicon oxides (e.g., silicon dioxide, zeolite), and carbon nanotubes (including carbon nanowires and carbon nanorods, etc.).

[0062] The metal chalcogenide is not particularly limited, and preferred examples include oxides of titanium, tin, zinc, tungsten, zirconium, hafnium, strontium, indium, cerium, yttrium, lanthanum, vanadium, niobium, aluminum, or tantalum, cadmium sulfide, cadmium selenide, etc. The crystal structure of the metal chalcogenide may be anatase, brookite, or rutile, with anatase and brookite being preferred.

[0063] The compound having a perovskite crystal structure is not particularly limited, and examples thereof include transition metal oxides. Examples include strontium titanate, calcium titanate, barium titanate, lead titanate, barium zirconate, barium stannate, lead zirconate, strontium zirconate, strontium tantalate, potassium niobate, bismuth ferrate, strontium barium titanate, barium lanthanum titanate, calcium titanate, sodium titanate, and bismuth titanate. Among these, strontium titanate and calcium titanate are preferred.

[0064] The material forming the porous layer is preferably an oxide of titanium, tin, zinc, zirconium, aluminum, or silicon, or carbon nanotubes, with titanium oxide or aluminum oxide being more preferred. The porous layer may be formed of at least one of the above-mentioned metal chalcogenides, compounds having a perovskite crystal structure, silicon oxides, and carbon nanotubes, or may be formed of a plurality of materials. The thickness of the porous layer is not particularly limited and is typically in the range of 0.05 to 100 μm, preferably 0.1 to 100 μm. When used as a solar cell, the thickness is preferably 0.1 to 50 μm, more preferably 0.2 to 30 μm. Regarding the thickness of the layers constituting the solar cell, unless otherwise specified, a scanning electron microscope is used to obtain a cross-sectional image of the solar cell in the stacking direction Ds, and 10 points corresponding to the thickness of each layer are measured. The average value of each of the 10 points is taken as the thickness of each layer constituting the solar cell.

[0065] The present invention is basically configured as described above. While the solar cell and the method for manufacturing the solar cell of the present invention have been described in detail above, the present invention is not limited to the above-described embodiments, and various improvements and modifications may be made without departing from the spirit and scope of the present invention.

[0066] The features of the present invention will be explained in more detail below with reference to examples. The materials, reagents, amounts of substances and their ratios, and procedures shown in the following examples can be changed as appropriate without departing from the spirit of the present invention. Therefore, the scope of the present invention is not limited to the following examples. In these examples, solar cells of Examples 1 to 13 and Comparative Examples 1 to 4 were fabricated and evaluated for moisture resistance, moist heat resistance, and adhesion. The results are shown in Table 1 below. The solar cells of Examples 1 to 13 and Comparative Examples 1 to 4 will now be described.

[0067] Example 1 Example 1 is a solar cell having the configuration shown in FIG. 1. <Preparation of Support Side Electrode / Support> A glass substrate having a thickness of 2 mm was used as the support. Fluorine-doped SnO was formed on the glass substrate as the support side electrode. ２ A conductive film (thickness: 300 nm) was formed. Fluorine-doped SnO ２ The conductive film, that is, the fluorine-doped tin oxide (FTO) conductive film, is a transparent conductive film. A support-side electrode formed on a support is called a support-side electrode / support.

[0068] <Preparation of Blocking Layer Solution> A 15% by mass isopropanol solution of titanium diisopropoxide bis(acetylacetonate) (manufactured by Aldrich) was diluted with 1-butanol to prepare a 0.02 M blocking layer solution. <Formation of Blocking Layer> Using the prepared 0.02 M blocking layer solution, a SnO film of the support side electrode / support was formed by spray pyrolysis at 450°C. ２ A blocking layer (thickness: 50 nm) made of titanium oxide was formed on the conductive film.

[0069] <Preparation of titanium oxide paste> Ethyl cellulose, lauric acid, and terpineol were added to an ethanol dispersion of titanium oxide (anatase, average particle size 20 nm) to prepare a titanium oxide paste. <Formation of electron transport layer> The prepared titanium oxide paste was applied onto the blocking layer by screen printing and fired in air at 500°C for 3 hours. Thereafter, the obtained fired titanium oxide was dissolved in 40 mM TiCl ４ After immersion in the aqueous solution, the sample was heated at 60°C for 1 hour and then at 500°C for 30 minutes to form TiO２ A porous layer (thickness: 250 nm) made of TiO was formed as an electron transport layer. <Formation of Photoelectric Conversion Layer> Lead iodide was dissolved in N,N-dimethylformamide to prepare a 1 M solution. ２ A film was formed on a porous layer made of lead iodide by spin coating. Furthermore, methylammonium iodide was dissolved in 2-propanol to prepare a 1M solution. The sample on which the lead iodide film was formed was immersed in this solution, and CH ３ NH ３ PbI ３ A photoelectric conversion layer made of the organic-inorganic perovskite compound was obtained. After that, an annealing treatment was carried out at 120° C. for 30 minutes.

[0070] <Preparation of Hole Transport Material Solution> Spiro-OMeTAD (180 mg) was dissolved in chlorobenzene (1 mL) as the hole transport material. To this chlorobenzene solution, lithium-bis(trifluoromethanesulfonyl)imide (170 mg) was dissolved in acetonitrile (1 mL) to form an acetonitrile solution (37.5 μL), and t-butylpyridine (TBP, 17.5 μL) were added and mixed to prepare a hole transport material solution. <Formation of Hole Transport Layer> The hole transport material solution was applied to the photoelectric conversion layer by spin coating, and the applied hole transport material solution was dried to form a hole transport layer (film thickness 0.1 μm). <Preparation of Sealing Layer-Side Electrode> Gold was vapor-deposited on the hole transport layer by vacuum deposition to prepare a sealing layer-side electrode (film thickness 100 nm). In this way, a laminated substrate having a layer structure of sealing layer-side electrode / hole transport layer / photoelectric conversion layer / electron transport layer / support-side electrode / support was obtained.

[0071] <Preparation of First Laminate> A PET (polyethylene terephthalate) film (Barrierox manufactured by Toray Industries, Inc.) with aluminum oxide vapor-deposited on the sealing layer was used. Plasma was irradiated onto the surface of the sealing layer from a plasma irradiation device described below under the following conditions, and a silicon oxide (SiO) layer with a thickness of 5 nm was formed as a first inorganic adhesive layer on the surface of the sealing layer by plasma CVD to obtain a first laminate. A first inorganic adhesive layer with a thickness of 5 nm was formed in 10 seconds. When forming the first inorganic adhesive layer, the plasma irradiation device was reciprocated in a direction parallel to the surface of the sealing layer. At this time, the speed of the plasma irradiation device was controlled so that each portion of the surface of the sealing layer was irradiated for a total of 10 seconds, thereby forming the first inorganic adhesive layer with a thickness of 5 nm. <Preparation of Second Laminate> The surface of the laminated substrate was irradiated with plasma from a plasma irradiation device described below under the following conditions, and a silicon oxide (SiO) layer with a thickness of 5 nm was formed as a second inorganic adhesive layer on the surface of the second laminate by plasma CVD to obtain a second laminate. The second inorganic adhesive layer with a thickness of 5 nm was formed in 10 seconds. When forming the second inorganic adhesive layer, the plasma irradiation device was reciprocated in a direction parallel to the surface of the laminated substrate. At this time, the speed of the plasma irradiation device was controlled so that each portion of the surface of the laminated substrate was irradiated for a total of 10 seconds, thereby forming the second inorganic adhesive layer with a thickness of 5 nm. <Lamination of First Laminate and Second Laminate> The first inorganic adhesive layer of the first laminate and the second inorganic adhesive layer of the second laminate were laminated 10 seconds after the first laminate or the second laminate was prepared. Next, the two laminates were bonded together using a pressure press while being heated to 100°C, forming a 10 nm thick silicon oxide (SiO) layer as an inorganic adhesive layer to obtain a solar cell. The pressure applied to the laminate of the first laminate and the second laminate by the pressure press was 20 MPa. The thickness of the inorganic adhesive layer in the solar cell was 10 nm.

[0072] (Plasma irradiation device) Atmospheric pressure plasma jet device (burette nozzle double tube type) Double tube structure: outer diameter of outer tube 15 mm, outer diameter of inner tube 8 mm Copper electrode placed on the outside of the outer tube Peak voltage: 11 kV Pulse width: 5 microseconds Bipolar pulse: 30 kHz Gas flowing through outer tube: helium gas (plasma generating gas, flow rate: 10 L / min) Gas flowing through inner tube: tetraethoxysilane (also known as TEOS, flow rate: 2 mg / min), oxygen gas (flow rate: 25 mL / min), nitrogen gas (flow rate: 500 mL / min) Treatment time: 10 seconds

[0073] (Example 2) Example 2 was the same as Example 1, except that the plasma treatment time for the sealing layer was changed to 2 seconds, the film thickness of the first inorganic adhesive layer was 1 nm, the plasma treatment time for the laminated base material was changed to 2 seconds, the film thickness of the second inorganic adhesive layer was 1 nm, and the thickness of the inorganic adhesive layer was 2 nm. (Example 3) Example 3 was the same as Example 1, except that the plasma treatment time for the sealing layer was changed to 1 second, the film thickness of the first inorganic adhesive layer was 0.5 nm, the plasma treatment time for the laminated base material was changed to 1 second, the film thickness of the second inorganic adhesive layer was 0.5 nm, and the thickness of the inorganic adhesive layer was 1 nm.

[0074] (Example 4) Example 4 differs from Example 1 in that an aluminum substrate (thickness 0.3 mm) was used as the conductive support instead of the support-side electrode / support of Example 1, the first inorganic adhesive layer and the second inorganic adhesive layer were produced using a roll-to-roll method, the film thickness of the first inorganic adhesive layer and the second inorganic adhesive layer was 1 nm, and the thickness of the inorganic adhesive layer was 2 nm, but the rest was the same as Example 1. For the roll-to-roll method, the apparatus 40 shown in FIG. 7 was used. On line P of the apparatus 40, a first inorganic adhesive layer with a film thickness of 1 nm was formed on the surface of the sealing layer with a plasma treatment time of 2 seconds. On line Q, a second inorganic adhesive layer with a film thickness of 1 nm was formed on the surface of the laminated substrate with a plasma treatment time of 2 seconds. Immediately thereafter, line P and line Q were merged, and the film formation surfaces of the first inorganic adhesive layer and the second inorganic adhesive layer were aligned. One second after the first inorganic adhesive layer and the second inorganic adhesive layer, whichever was prepared first, the first inorganic adhesive layer of the first laminate and the second inorganic adhesive layer of the second laminate were laminated to produce a laminate. The thickness of the inorganic adhesive layer in the laminate was set to 2 nm. Next, after winding up the laminate, a portion of the laminate was cut out to a predetermined size, and the cut laminate was bonded using a pressure press while heated to 100 ° C. to obtain a solar cell. In the roll-to-roll method, instead of operating the plasma irradiation device, the transport speed of the sealing layer on line P and the transport speed of the laminated substrate on line Q were adjusted according to the plasma treatment time.

[0075] (Example 5) Example 5 was the same as Example 1, except that tetraethoxysilane (TEOS) was changed to trimethylaluminum, the inorganic adhesive layer was an AlO (aluminum oxide) layer, the film thickness of the first inorganic adhesive layer and the second inorganic adhesive layer was 1 nm, and the thickness of the inorganic adhesive layer was 2 nm. In Example 5, the plasma treatment time for the sealing layer was changed to 2 seconds, and the plasma treatment time for the laminated substrate was changed to 2 seconds. (Example 6) Example 6 was the same as Example 4, except that tetraethoxysilane (TEOS) was changed to trimethylaluminum, and the inorganic adhesive layer was an AlO (aluminum oxide) layer. (Example 7) Example 7 was the same as Example 4, except that tetraethoxysilane (TEOS) was changed to trisdimethylaminosilane, and the inorganic adhesive layer was an SiN (silicon nitride) layer.

[0076] (Example 8) Example 8 was the same as Example 4, except that tetraethoxysilane (TEOS) was replaced with trimethylamine, the gas flowing through the inner tube of the plasma irradiation device was trimethylamine and nitrogen gas (flow rate: 3000 mL / min), and the inorganic adhesive layer was an AlN (aluminum nitride) layer. (Example 9) Example 9 was the same as Example 4, except that the film thickness of the first inorganic adhesive layer was 0.5 nm, the film thickness of the second inorganic adhesive layer was 1.5 nm, and the thickness of the inorganic adhesive layer was 2 nm. In Example 9, the plasma treatment time for the sealing layer was changed to 1 second, and the plasma treatment time for the laminated substrate was changed to 3 seconds. (Example 10) Example 10 was the same as Example 4, except that the film thickness of the first inorganic adhesive layer was 1.5 nm, the film thickness of the second inorganic adhesive layer was 0.5 nm, and the thickness of the inorganic adhesive layer was 2 nm. In Example 10, the plasma treatment time for the sealing layer was changed to 3 seconds, and the plasma treatment time for the laminated substrate was changed to 1 second.

[0077] (Example 11) Example 11 was the same as Example 4, except that the film thickness of the first inorganic adhesive layer was 0.8 nm, the film thickness of the second inorganic adhesive layer was 0.5 nm, and the thickness of the inorganic adhesive layer was 1.2 nm. In Example 11, the plasma treatment time for the sealing layer was changed to 1.6 seconds, and the plasma treatment time for the laminated substrate was changed to 2.4 seconds. (Example 12) Example 12 is a solar cell having the configuration shown in FIG. 3. Example 12 was the same as Example 4, except that an aluminum substrate (thickness: 0.5 mm) was used as the conductive support instead of the support-side electrode / support of Example 1. (Example 13) Example 13 was the same as Example 2, except that 60 seconds after the first laminate or the second laminate was produced, the first inorganic adhesive layer of the first laminate and the second inorganic adhesive layer of the second laminate were laminated, and then heated to 100°C and bonded using a pressure press to form an inorganic adhesive layer, thereby obtaining a solar cell.

[0078] (Comparative Example 1) Comparative Example 1 was the same as Example 2, except that the first inorganic adhesive layer of the first laminate and the second inorganic adhesive layer of the second laminate were laminated 500 seconds after the first laminate and the second laminate were produced first, and then the laminates were bonded together using a pressure press while heated to 100°C to form an inorganic adhesive layer, thereby obtaining a solar cell. (Comparative Example 2) Comparative Example 2 was the same as Example 1, except that the first inorganic adhesive layer and the second inorganic adhesive layer were formed using a sputtering method, and the film thickness of the first inorganic adhesive layer was 1 nm, the film thickness of the second inorganic adhesive layer was 1 nm, and the thickness of the inorganic adhesive layer was 2 nm. (Comparative Example 3) Comparative Example 3 was the same as Comparative Example 1, except that an aluminum substrate (thickness 0.5 mm) was used as the conductive support instead of the support-side electrode / support.

[0079] (Comparative Example 4) Comparative Example 4 was the same as Example 1, except that an epoxy resin was used instead of the inorganic adhesive layer. In Comparative Example 4, 1.0 g of hydrotalcite and an epoxy resin manufactured by Epoch Co., Ltd. (E-01-001 (product number) base material: 4.0 g, curing agent: 2.0 g) were mixed and applied to a laminated substrate of a sealing layer side electrode / hole transport layer / photoelectric conversion layer / electron transport layer / support side electrode / support using spin coating (1000 rpm, 120 seconds), and unnecessary portions were removed with acetone. Next, a sealing layer was attached thereto and heated at 80 ° C. for 1 hour to form a solar cell. A PET film (Barrierox manufactured by Toray Industries, Inc.) on which aluminum oxide was vapor-deposited was used as the sealing layer.

[0080] The evaluation items of moisture resistance, moist heat resistance, and adhesion are explained below. <Moisture Resistance> Three solar cells were fabricated for each of the above-mentioned Examples 1 to 13 and Comparative Examples 1 to 4. A cell characteristics test was performed on each of the three solar cells to measure the current. The average value of the three solar cells was then taken as the initial current for each of Examples 1 to 13 and Comparative Examples 1 to 4. The cell characteristics test was performed using a solar simulator "WXS-85H" (manufactured by WACOM Corporation) and a 1000 W / m ray irradiated from a xenon lamp passed through an AM (Air Mass) 1.5 filter. ２The test was performed by irradiating the solar cell with simulated sunlight from the encapsulation layer side. In the cell characteristic test, the current-voltage characteristics of the solar cell were measured using an I-V tester, and the initial photoelectric conversion efficiency (η (%)) was determined. Three solar cells of each of Examples 1 to 13 and Comparative Examples 1 to 4 were each stored in a thermo-hygrostat at a temperature of 25°C and a humidity of 60% RH (Relative Humidity) for 24 hours, and then the above-mentioned cell characteristic test was performed to measure the photoelectric conversion efficiency (η (%)). The average value of the three solar cells was taken as the photoelectric conversion efficiency (η (%)) after storage for each of the solar cells of Examples 1 to 13 and Comparative Examples 1 to 4. The moisture resistance of the solar cell was evaluated according to the following evaluation criteria from the rate of decrease in photoelectric conversion efficiency calculated by the following formula: Decrease rate (%) = 100 - {100 x (photoelectric conversion efficiency after storage) / (initial photoelectric conversion efficiency)} - Moisture resistance evaluation criteria - A: Decrease rate is less than 10% B: Decrease rate is 10% or more and less than 20% C: Decrease rate is 20% or more and less than 30% D: Decrease rate is 30% or more

[0081] <Moisture and Heat Resistance> Three solar cells were fabricated for each of the above-mentioned Examples 1 to 13 and Comparative Examples 1 to 4. A cell characteristic test was conducted on each of the three solar cells, and the current was measured. The average value of the three solar cells was taken as the initial current for each of Examples 1 to 13 and Comparative Examples 1 to 4. The cell characteristic test was conducted using a solar simulator "WXS-85H" (manufactured by WACOM Corporation), with a 1000 W / m irradiance from a xenon lamp passed through an AM1.5 filter. ２The test was carried out by irradiating the solar cells with simulated sunlight from the sealing layer side. The current-voltage characteristics of the solar cells were measured using an I-V tester. Three solar cells from each of Examples 1 to 13 and Comparative Examples 1 to 4 were each left standing in a constant temperature and humidity chamber at 60% RH and 45°C for 80 hours, and then the above-mentioned battery characteristic test was carried out to measure the current. The average value of the three solar cells was taken as the current after standing for each of Examples 1 to 13 and Comparative Examples 1 to 4. The moist heat resistance of the solar cells was evaluated according to the following evaluation criteria using the rate of decrease in current calculated by the following formula: Rate of decrease (%) = [(initial current - current after standing) / (initial current)] × 100 - Moisture and heat resistance evaluation criteria - A: Rate of decrease less than 10% B: Rate of decrease 10% or more but less than 20% C: Rate of decrease 20% or more but less than 30% D: Rate of decrease 30% or more

[0082] (Adhesion) In the solar cells of Examples 1 to 13 and Comparative Examples 1 to 4 described above, when the second inorganic adhesive layer was formed on the surface of the laminated substrate, a PET film 50 mm wide x 10 mm long was sandwiched between the ends of the laminated substrate, providing a portion where the laminated substrate and the sealing layer were not in close contact, i.e., a non-adhesion portion. Other than this, the solar cells were produced in the same manner as the solar cells of Examples 1 to 13 and Comparative Examples 1 to 4 described above. Each of the solar cells of Examples 1 to 13 and Comparative Examples 1 to 4 described above was cut into a size of 50 mm x 25 mm to prepare a test specimen. In the test specimen, the glass substrate side of the laminated substrate was facing the base, and the glass substrate and the base were attached and fixed using double-sided tape. Next, the non-adhesion portion of the sealing layer in contact with the laminated substrate in the test specimen was folded back. The folded portion of the non-adhesion portion was pulled in a 180° direction (peel speed: 5 mm / sec) and the maximum load (N / 25 mm) was measured using a peel tester (Shimadzu Corporation, universal testing machine AGS-100NX). The obtained maximum load (N / 25 mm) was evaluated according to the following evaluation criteria. -Adhesion evaluation criteria- A: Adhesion strength of 20 N / 25 mm or more B: Adhesion strength of 10 N / 25 mm or more and less than 20 N / 25 mm C: Adhesion strength of 1 N / 25 mm or more and less than 10 N / 25 mm D: Adhesion strength of less than 1 N / 25 mm

[0083] <Measurement of atomic ratio of inorganic adhesive layer> A PET film (Lumirror (registered trademark) #125-T60, manufactured by Toray Industries, Inc.) and a release film (JOL, manufactured by Nippa Corporation) were prepared. A second inorganic adhesive layer was formed on the PET film using the methods described above in Examples 1 to 13 and Comparative Examples 1 to 4. A first inorganic adhesive layer was formed on the release film using the methods described above in Examples 1 to 13 and Comparative Examples 1 to 4. Using the methods described above in Examples 1 to 13 and Comparative Examples 1 to 4, the PET film and the release film were laminated and heated to 100°C while being bonded using a pressure press to obtain an inorganic adhesive layer. Next, the release film was peeled off. Next, the inorganic adhesive layer on the surface of the PET film was subjected to X-ray photoelectron spectroscopy analysis using an XPS device (AXIS-ULTRA, manufactured by Shimadzu Corporation). Si, Al, O, and N were measured along the thickness direction of the inorganic adhesive layer, and the atomic ratios of Si, Al, O, and N were calculated from the measurement results.

[0084]

[0085] As shown in Table 1, Examples 1 to 13 had superior moisture resistance, moist heat resistance, and adhesion compared to Examples 1 to 4. Furthermore, all of Examples 1 to 13 had photoelectric conversion efficiencies sufficient for normal operation as solar cells. Comparative Examples 1 and 3 did not have a region with a low atomic ratio, resulting in poor moisture resistance, moist heat resistance, and adhesion. Comparative Example 2 used a sputtering method. When a sputtering method was used, adhesion between the first inorganic adhesive layer and the second inorganic adhesive layer was poor, making it difficult to adhere the sealing layer, resulting in poor moisture resistance, moist heat resistance, and adhesion. Comparative Example 4 did not use an inorganic adhesive layer, but instead used an epoxy resin to bond the sealing layer, resulting in poor moisture resistance, moist heat resistance, and adhesion. From Examples 1 to 3, it can be seen that a thinner inorganic adhesive layer is preferable because it provides even better moisture resistance, moist heat resistance, and adhesion. From Examples 4, 6 to 8, and 12, it was found that oxides are preferable to nitrides as the compounds constituting the inorganic adhesive layer because they have better moisture resistance, moist heat resistance, and adhesion. From Examples 4, 9 to 11, which use the same compound constituting the inorganic adhesive layer, Example 4, in which the film thickness of the first inorganic adhesive layer and the film thickness of the second inorganic adhesive layer are the same, has a higher adhesion between the first inorganic adhesive layer and the second inorganic adhesive layer because the region of the second ratio is located in the center of the thickness direction of the inorganic adhesive layer. Therefore, Example 4 has better adhesion and also better moisture resistance and moist heat resistance than Examples 9 to 11.

[0086] REFERENCE SIGNS LIST 10, 11 Solar cell 12 Support 13 Conductive support 14 Support-side electrode 15 Electron transport layer 16 Photoelectric conversion layer 17 Hole transport layer 18 Sealing layer-side electrode 18a, 22a, 26a, 28a Surface 20 Inorganic adhesive layer 20a First contact surface 20b Second contact surface 22 Sealing layer 22b Surface 24 Photoelectric conversion section 25 Region 26 First inorganic adhesive layer 27 Laminated base material 28 Second inorganic adhesive layer 30 First laminate 32 Second laminate 34 Laminate 40 Apparatus 41 Conveying shaft 42, 44 Conveying roller 43 Conveying shaft 45, 48 Film-forming apparatus 46 Roller pair 46a, 46b Roller 47 Winding shaft Ds Stacking direction Dt Thickness direction Ls Sunlight P, Q line

Claims

1. A solar cell having a layer structure in which a support, a support-side electrode, an electron transport layer, a photoelectric conversion layer, a hole transport layer, a sealing layer-side electrode, an inorganic adhesive layer, and a sealing layer are stacked in this order, wherein the photoelectric conversion layer contains a perovskite compound, and the inorganic adhesive layer is composed of a compound containing one of an oxide and a nitride containing one of the elements Si and Al, and in the thickness direction of the inorganic adhesive layer, an atomic ratio of the element contained in the compound to oxygen or nitrogen contained in the compound at a first contact surface of the inorganic adhesive layer in contact with the sealing layer and a second contact surface of the inorganic adhesive layer in contact with the sealing layer-side electrode is a first ratio, and the inorganic adhesive layer has a region between the first contact surface and the second contact surface in the thickness direction of the inorganic adhesive layer where the atomic ratio of the compound is a second ratio lower than the first ratio.

2. A solar cell having a layer structure in which a conductive support, an electron transport layer, a photoelectric conversion layer, a hole transport layer, a sealing layer side electrode, an inorganic adhesive layer, and a sealing layer are stacked in this order, wherein the photoelectric conversion layer contains a perovskite compound, and the inorganic adhesive layer is composed of a compound containing one of an oxide and a nitride containing one of the elements Si and Al, and in the thickness direction of the inorganic adhesive layer, an atomic ratio of the element contained in the compound to oxygen or nitrogen contained in the compound at a first contact surface of the inorganic adhesive layer in contact with the sealing layer and a second contact surface of the inorganic adhesive layer in contact with the sealing layer side electrode is a first ratio, and the inorganic adhesive layer has a region between the first contact surface and the second contact surface in the thickness direction of the inorganic adhesive layer where the atomic ratio of the compound is a second ratio lower than the first ratio.

3. The solar cell according to claim 1 or 2, wherein the inorganic adhesive layer has a thickness of 0.3 to 5 nm.

4. The solar cell according to claim 1 or 2, wherein the atomic ratio of the compound is 1.0 to 3.

0.

5. The solar cell according to claim 1 or 2, wherein the region in which the atomic ratio of the compound is the second ratio is located at the center in the thickness direction of the inorganic adhesive layer.

6. A method for manufacturing a solar cell having a layer structure in which a support, a support-side electrode, an electron transport layer, a photoelectric conversion layer, a hole transport layer, a sealing layer-side electrode, an inorganic adhesive layer, and a sealing layer are laminated in this order, comprising: a first forming step of forming a first inorganic adhesive layer by a plasma CVD method on a surface of the sealing layer facing the sealing layer-side electrode, and forming a first laminate comprising the first inorganic adhesive layer on the surface of the sealing layer facing the sealing layer-side electrode; and a second forming step of forming a second inorganic adhesive layer by the plasma CVD method on a surface of the sealing layer-side electrode of a laminated base material in which the support, the support-side electrode, the electron transport layer, the photoelectric conversion layer, the hole transport layer, and the sealing layer-side electrode are laminated in this order, and forming a second laminate comprising the second inorganic adhesive layer on the surface of the sealing layer-side electrode of the laminated base material. and a third formation step of laminating the first inorganic adhesive layer of the first laminate and the second inorganic adhesive layer of the second laminate within 60 seconds after formation of the first laminate or the second laminate whichever is formed first, to form the inorganic adhesive layer, wherein the first inorganic adhesive layer and the second inorganic adhesive layer are composed of a compound containing one of an oxide and a nitride containing one of the elements Si and Al.

7. A method for manufacturing a solar cell having a layer structure in which a conductive support, an electron transport layer, a photoelectric conversion layer, a hole transport layer, a sealing layer side electrode, an inorganic adhesive layer, and a sealing layer are laminated in this order, comprising: a first forming step of forming a first inorganic adhesive layer by a plasma CVD method on a surface of the sealing layer facing the sealing layer side electrode, and forming a first laminate comprising the first inorganic adhesive layer on the surface of the sealing layer facing the sealing layer side electrode; and a second forming step of forming a second inorganic adhesive layer by the plasma CVD method on a surface of the sealing layer side electrode of a laminated base material in which the conductive support, the electron transport layer, the photoelectric conversion layer, the hole transport layer, and the sealing layer side electrode are laminated in this order, and forming a second laminate comprising the second inorganic adhesive layer on the surface of the sealing layer side electrode of the laminated base material. and a third formation step of laminating the first inorganic adhesive layer of the first laminate and the second inorganic adhesive layer of the second laminate within 60 seconds after formation of the first laminate or the second laminate whichever is formed first, to form the inorganic adhesive layer, wherein the first inorganic adhesive layer and the second inorganic adhesive layer are composed of a compound containing one of an oxide and a nitride containing one of the elements Si and Al.

8. The method for manufacturing a solar cell described in claim 6 or 7, wherein the first laminate and the second laminate are individual sheets, and the third formation step is carried out after the first formation step and the second formation step.

9. A method for manufacturing a solar cell as described in claim 6 or 7, wherein the first formation step and the second formation step are carried out by roll-to-roll, and the third formation step is carried out after the first formation step and the second formation step.

10. The method for manufacturing a solar cell according to claim 6 or 7, wherein the first inorganic adhesive layer and the second inorganic adhesive layer have the same thickness.

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