Photoelectric conversion element, photoelectric conversion module, paddle, and method for manufacturing photoelectric conversion element

Abstract

This method for manufacturing a photoelectric conversion element comprises: a step (S1) for preparing a glass substrate having an ion exchange layer in which at least some alkali metal ions (excluding potassium ions) are substituted with potassium ions; a step (S4) for forming a precursor film on the glass substrate; and a step (S5) for heating the glass substrate and the precursor film.

Description

Photoelectric conversion element, photoelectric conversion module, paddle, and method for manufacturing photoelectric conversion element

[0001] The present invention relates to a photoelectric conversion element, a photoelectric conversion module, a paddle, and a method for manufacturing a photoelectric conversion element.

[0002] A photoelectric conversion element that converts light energy into electrical energy is known (see Patent Document 1 below). The photoelectric conversion element described in Patent Document 1 has a so-called CIS-based or CIGS-based photoelectric conversion layer. The CIS-based or CIGS-based photoelectric conversion layer is a I-III-VI type having a chalcopyrite structure. ２ Such a CIS-based or CIGS-based photoelectric conversion layer is formed by depositing a precursor film made of group I (Cu, etc.) and group III (In, Ga, etc.) elements, and then selenizing and / or sulfurizing the precursor film.

[0003] Patent Document 1 discloses a method for manufacturing a photoelectric conversion element in which a decrease in photoelectric conversion efficiency due to a shortage of alkali ions in the photoelectric conversion layer is suppressed by bringing the photoelectric conversion layer into contact with a solution containing carbonate ions or bicarbonate ions and alkali metal ions.

[0004] JP 2020-181922 A JP 2020-200208 A

[0005] The inventors of the present application have newly discovered the cause of the potassium deficiency in the photoelectric conversion layer. When the amount of potassium contained in the photoelectric conversion layer decreases, the photoelectric conversion efficiency of the photoelectric conversion element may decrease.

[0006] Therefore, there is a demand for a method for manufacturing a photoelectric conversion element that can suppress the deficiency of potassium element in the photoelectric conversion layer, and a photoelectric conversion element manufactured by such a method.

[0007] A method for manufacturing a photoelectric conversion element according to one embodiment includes the steps of preparing a glass substrate having an ion exchange layer in which at least a portion of alkali metal ions (excluding potassium ions) are substituted with potassium ions, forming a precursor film on the glass substrate, and heating the glass substrate and the precursor film.

[0008] A photoelectric conversion element according to one embodiment includes a glass substrate having an ion exchange layer in which at least a portion of alkali metal ions (excluding potassium ions) are substituted with potassium ions, and a photoelectric conversion layer including a chalcogen compound semiconductor formed on the glass substrate.

[0009] A photoelectric conversion module according to one embodiment includes a plurality of the above photoelectric conversion elements.

[0010] A paddle according to one aspect includes the above-described photoelectric conversion module.

[0011] FIG. 1 is a schematic plan view of a photoelectric conversion element according to an embodiment. FIG. 2 is a schematic cross-sectional view of the photoelectric conversion element taken along line 2A-2A in FIG. 1. FIG. 3 is a flowchart of a method for manufacturing a photoelectric conversion element according to an embodiment. FIG. 4 is a schematic cross-sectional view illustrating a step in the method for manufacturing a photoelectric conversion element according to an embodiment. FIG. 5 is a graph illustrating the concentration of an alkali metal element in a glass substrate. FIG. 6 is a schematic diagram illustrating a step following FIG. 4. FIG. 7 is a schematic diagram illustrating a step following FIG. 6. FIG. 8 is a schematic diagram illustrating a step following FIG. 7. FIG. 9 is a schematic diagram illustrating a step following FIG. 8. FIG. 10 is a graph illustrating the results of PL (photoluminescence) evaluation in Experimental Example 2 and Reference Example 2. FIG. 11 is a graph illustrating the results of current-voltage characteristics (IV characteristics) of the photoelectric conversion elements according to Experimental Example 2 and Reference Example 2. FIG. 12 is a schematic plan view of a photoelectric conversion module according to an embodiment. FIG. 13 is a schematic perspective view of an artificial satellite equipped with a photoelectric conversion module.

[0012] Hereinafter, embodiments will be described with reference to the drawings. In the following drawings, the same or similar parts are denoted by the same or similar reference numerals. However, it should be noted that the drawings are schematic and the ratios of the dimensions may differ from those of the actual parts.

[0013] [Photoelectric Conversion Element] Fig. 1 is a schematic plan view of a photoelectric conversion element according to one embodiment, and Fig. 2 is a schematic cross-sectional view of the photoelectric conversion element taken along line 2A-2A in Fig. 1.

[0014] The photoelectric conversion element 10 according to this embodiment may be a thin-film type photoelectric conversion element, and is preferably a solar cell element that converts light energy into electrical energy.

[0015] The photoelectric conversion element 10 has a glass substrate 20 that serves as a base on which each film is formed. The shape and dimensions of the glass substrate 20 are determined appropriately depending on the size of the photoelectric conversion element 10, etc.

[0016] The glass substrate 20 may be a substrate having an ion-exchange layer 20a in which at least a portion of the alkali metal ions (excluding potassium ions) are substituted with potassium ions (see also FIG. 4). The ion-exchange layer 20a may be, for example, a layer in which at least a portion of the lithium ions and / or sodium ions in the glass material are substituted with potassium ions.

[0017] The ion exchange layer 20a may be formed near the surface of the glass substrate 20 on the side where the photoelectric conversion layer 26 described later is formed. However, the ion exchange layer may be formed near both surfaces of the glass substrate 20.

[0018] The thickness of the ion exchange layer 20a may be determined by the range from the surface of the glass substrate 20 (the surface into which potassium elements have been introduced) to the range in which the potassium ion concentration reaches 5% of the maximum concentration (corresponding to range D in Figure 5).

[0019] The thickness of the ion exchange layer 20a may be, for example, 5 μm or more, preferably 8 μm or more, and more preferably 10 μm or more. The upper limit of the thickness of the ion exchange layer 20a is not particularly limited and may be, for example, 200 μm or less, preferably 150 μm or less, and more preferably 100 μm or less.

[0020] Preferably, the ratio of potassium to all alkali metal elements may be maximum at at least a portion of the depth of the ion exchange layer, where the ratio of potassium to all alkali metal elements is defined by "(amount of potassium) / (total amount of all alkali metal elements)" at a certain depth of the glass substrate.

[0021] The glass substrate 20 may be so-called chemically strengthened glass. Chemically strengthened glass has a so-called compressive stress layer formed by substituting alkali metal ions (ion exchange). In this case, the ion exchange layer 20a may correspond to the compressive stress layer of the chemically strengthened glass. The compressive stress layer of the chemically strengthened glass is formed, for example, by substituting at least a portion of the lithium ions and / or sodium ions in sodium- and / or lithium-containing glass with potassium ions.

[0022] The photoelectric conversion element 10 may include at least a first electrode layer 22, a second electrode layer 24, and a photoelectric conversion layer 26 provided between the first electrode layer 22 and the second electrode layer 24. Specifically, the photoelectric conversion element 10 has a structure in which the first electrode layer 22, the photoelectric conversion layer 26, and the second electrode layer 24 are stacked in this order on a glass substrate 20.

[0023] The photoelectric conversion element 10 may have an underlayer 21 between the glass substrate 20 and the first electrode layer 22. The underlayer 21 is not essential and may not be provided. The underlayer 21 may be made of, for example, SiO ２ , SiO ｘ , MoSi ２ , MoSi ｘ , SiN, SiNx, Al ２ O ３ , Al ｘ O ｙ , Ti, TiO ２ , TiO ｘ , TiN, and TiNx, where x and y are positive real numbers and may be selected appropriately.

[0024] The thickness of the underlayer 21 may be, for example, in the range of 0.5 to 100 nm, preferably 1 to 50 nm, and more preferably 2 to 30 nm.

[0025] The photoelectric conversion layer 26 is a layer that contributes to the mutual conversion between light energy and electrical energy. In a solar cell element that converts light energy into electrical energy, the photoelectric conversion layer 26 is sometimes called a light absorption layer.

[0026] The first electrode layer 22 and the second electrode layer 24 are adjacent to the photoelectric conversion layer 26. In this specification, the term "adjacent" means not only that both layers are in direct contact with each other, but also that both layers are close to each other via another layer.

[0027] The first electrode layer 22 is provided between the photoelectric conversion layer 26 and the glass substrate 20. The second electrode layer 24 is located on the opposite side of the photoelectric conversion layer 26 from the glass substrate 20. Therefore, the first electrode layer 22 is located on the opposite side of the photoelectric conversion layer 26 from the second electrode layer 24.

[0028] In the present embodiment, the second electrode layer 24 may be formed of a transparent electrode layer. When the second electrode layer 24 is formed of a transparent electrode layer, light incident on the photoelectric conversion layer 26 or emitted from the photoelectric conversion layer 26 passes through the second electrode layer 24.

[0029] When the second electrode layer 24 is a transparent electrode layer, the first electrode layer 22 may be an opaque electrode layer or a transparent electrode layer. The first electrode layer 22 may be formed of a metal such as molybdenum, titanium, or chromium. Although not particularly limited, the thickness of the first electrode layer 22 may be, for example, 50 nm to 1500 nm, preferably 50 nm to 1200 nm, more preferably 50 nm to 800 nm, and even more preferably 50 nm to 500 nm.

[0030] In the present embodiment, as a preferred example, the second electrode layer 24 may be formed of an n-type semiconductor, more specifically, a material having n-type conductivity and relatively low resistance. The second electrode layer 24 can function both as an n-type semiconductor and a transparent electrode layer. The second electrode layer 24 includes, for example, a metal oxide doped with a Group III element (B, Al, Ga, or In). Here, the "group" of an element in this specification is based on the short periodic table (the same applies hereinafter).

[0031] Examples of metal oxides that form the second electrode layer 24 include ZnO and SnO. ２ The second electrode layer 24 may be, for example, indium tin oxide (In ２ O３ : Sn), indium titanium oxide (In ２ O ３ :Ti), indium zinc oxide (In ２ O ３ :Zn), tin-zinc-doped indium oxide (In ２ O ３ : Sn, Zn), tungsten-doped indium oxide (In ２ O ３ :W), hydrogen-doped indium oxide (In ２ O ３ :H), indium gallium zinc oxide (InGaZnO ４ ), zinc tin oxide (ZnO:Sn), fluorine-doped tin oxide (SnO ２ :F), gallium-doped zinc oxide (ZnO:Ga), boron-doped zinc oxide (ZnO:B), aluminum-doped zinc oxide (ZnO:Al), and the like can be selected.

[0032] Although not particularly limited, the thickness of the second electrode layer 24 may be, for example, 0.5 μm to 2.5 μm.

[0033] The photoelectric conversion layer 26 may include, for example, a p-type semiconductor. In a specific example, the photoelectric conversion layer 26 may function as, for example, a polycrystalline or microcrystalline p-type compound semiconductor layer.

[0034] In this embodiment, the photoelectric conversion layer 26 includes at least a group I element and a group III element. Specifically, the photoelectric conversion layer 26 may include a chalcogen compound semiconductor including at least a group I element and a group III element. A chalcogen compound semiconductor is a compound including at least one chalcogen element. The chalcogen compound includes, for example, a sulfide, a selenide, and / or a telluride.

[0035] Specifically, the photoelectric conversion layer 26 is made of I-III-VI SiO2 having a chalcopyrite structure. ２The photoelectric conversion layer 26 may include a group I compound semiconductor layer. Here, the group I element may be selected from copper (Cu), silver (Ag), gold (Au), etc. The group III element may be selected from indium (In), gallium (Ga), aluminum (Al), etc. Furthermore, the photoelectric conversion layer 26 may include tellurium (Te) as a group VI element in addition to selenium (Se) and sulfur (S).

[0036] Instead, the photoelectric conversion layer 26 is made of I, which is a CZTS-based chalcogen compound containing Cu, Zn, Sn, S, or Se. ２ -(II-IV)-VI ４ A typical example of a CZTS-based chalcogen compound semiconductor is a Cu ２ ZnSnSe ４ , Cu ２ ZnSn(S,Se) ４ and the like.

[0037] The photoelectric conversion layer 26 contains an alkali metal element such as Li, Na, K, Rb, or Cs. Preferably, the photoelectric conversion layer 26 contains potassium.

[0038] The thickness of the photoelectric conversion layer 26 may be, for example, in the range of 0.5 μm to 5.0 μm, and preferably in the range of 1.0 μm to 3.0 μm.

[0039] The photoelectric conversion element 10 may have a first buffer layer 27 between the photoelectric conversion layer 26 and the first electrode layer 22. In this case, the first buffer layer 27 may be made of a semiconductor material having the same conductivity type as the first electrode layer 22, or may be made of a semiconductor material having a different conductivity type. The first buffer layer 27 may be made of a material having a higher electrical resistance than the first electrode layer 22.

[0040] The first buffer layer 27 is not particularly limited, and may be, for example, a layer containing a chalcogenide compound of a transition metal element having a layered structure. Specifically, the first buffer layer 27 may be composed of a compound made of a transition metal material such as M, W, Ti, V, Cr, Nb, or Ta and a chalcogen element such as O, S, or Se. The first buffer layer 27 may be, for example, M(Se,S) ２ Layer, MоSe２ Layer or MoS ２ The first buffer layer 27 can be formed on the surface of the first electrode layer 22 when the photoelectric conversion layer 26 is formed by chalcogenizing a precursor layer used as a precursor of the photoelectric conversion layer 26.

[0041] The photoelectric conversion element 10 may have a second buffer layer 28 between the photoelectric conversion layer 26 and the second electrode layer 24. In this case, the second buffer layer 28 may be made of a semiconductor material having the same conductivity type as the second electrode layer 24, or may be made of a semiconductor material having a different conductivity type. The second buffer layer 28 may be made of a material having a higher electrical resistance than the second electrode layer 24.

[0042] The second buffer layer 28 is formed on the photoelectric conversion layer 26. Although not particularly limited, the thickness of the second buffer layer 28 may be, for example, 10 nm to 100 nm.

[0043] The second buffer layer 28 can be made of a compound selected from compounds containing zinc (Zn), cadmium (Cd), and indium (In). Examples of compounds containing zinc include ZnO, ZnS, and Zn(OH). ２ , or mixed crystals thereof such as Zn(O,S) and Zn(O,S,OH), as well as ZnMgO and ZnSnO. Compounds containing cadmium include, for example, CdS, CdO, or mixed crystals thereof such as Cd(O,S) and Cd(O,S,OH). Compounds containing indium include, for example, In ２ S ３ , In ２ O ３ or a mixed crystal thereof, In ２ (O, S) ３ , In ２ (O, S, OH) ３ There is In ２ O ３ , In ２ S ３ , In(OH) ｘ The second buffer layer 28 may have a laminated structure of these compounds.

[0044] The second buffer layer 28 has the effect of improving characteristics such as photoelectric conversion efficiency, but it can be omitted. When the second buffer layer 28 is omitted, the second electrode layer 24 is formed directly on the photoelectric conversion layer 26.

[0045] It should be noted that the stacked structure of the photoelectric conversion element 10 is not limited to the above embodiment and can take various forms. For example, the photoelectric conversion element 10 may have a configuration in which both an n-type semiconductor and a p-type semiconductor are sandwiched between a first electrode layer and a second electrode layer. In this case, the second electrode layer does not need to be composed of an n-type semiconductor. Furthermore, the photoelectric conversion element 10 is not limited to a p-n junction type structure, and may have a p-i-n junction type structure that includes an intrinsic semiconductor layer (i-type semiconductor) between an n-type semiconductor and a p-type semiconductor.

[0046] The photoelectric conversion element 10 may include a collecting electrode 30 adjacent to the second electrode layer 24. The collecting electrode 30 collects charge carriers from the second electrode layer 24 and is made of a conductive material. The collecting electrode 30 may be in direct contact with the second electrode layer 24. From the viewpoint of improving power generation efficiency, it is preferable that the area of ​​the collecting electrode 30 is as small as possible.

[0047] The collecting electrode 30 may have a plurality of substantially linear first portions 31 and second portions 32 connected to the first portions 31. The first portions 31 may also be referred to as "fingers." The second portions 32 may also be referred to as "bus bars."

[0048] The first portions 31 are arranged at intervals from one another. The plurality of linear first portions 31 are connected to the second portions 32. The first portions 31 serve to conduct electricity generated in the photoelectric conversion layer 26 to the second portions 32.

[0049] The photoelectric conversion element 10 may include wiring 50 joined to the collecting electrode 30. The wiring 50 may be joined to the second portion 32 of the collecting electrode 30. The wiring 50 may include, for example, an interconnector 52 for electrically connecting to the outside of the photoelectric conversion element 10, and / or a connector 54 for connecting to a bypass diode that electrically bypasses a cell that cannot perform photoelectric conversion.

[0050] The collecting electrodes 30, the wiring 50, the interconnector 52 and / or the connector 54 are not essential and may not be provided.

[0051] [Method for Manufacturing Photoelectric Conversion Element] Next, a method for manufacturing a photoelectric conversion element according to an embodiment will be described with reference to FIGS. 3 to 9. FIG. 3 is a diagram showing a flowchart of a method for manufacturing a photoelectric conversion element according to an embodiment. FIG. 4 is a schematic cross-sectional view for explaining one step in a method for manufacturing a photoelectric conversion element according to an embodiment. FIG. 5 is a graph for explaining the concentration of an alkali metal element in a glass substrate. FIG. 6 is a schematic diagram for explaining a step following FIG. 4. FIG. 7 is a schematic diagram for explaining a step following FIG. 6. FIG. 8 is a schematic diagram for explaining a step following FIG. 7. FIG. 9 is a schematic diagram for explaining a step following FIG. 8.

[0052] The method for manufacturing a photoelectric conversion element according to this embodiment may include step S1 of preparing a glass substrate, step S2 of forming a base layer, step S3 of forming a first electrode layer, step S4 of forming a precursor film, step S5 of heating the precursor film, step S6 of forming a second buffer layer, step S7 of forming the second electrode layer, and step S8 of forming a collecting electrode. Here, step S2 of forming the base layer, step S3 of forming the first electrode layer, step S6 of forming the second buffer layer, step S7 of forming the second electrode layer, and step S8 of forming the collecting electrode are not essential and may not be performed if unnecessary.

[0053] First, step S1 of preparing a glass substrate is carried out as shown in Fig. 4. The shape and dimensions of the glass substrate 20 are determined appropriately depending on the size of the photoelectric conversion element 10 to be manufactured.

[0054] The glass substrate 20 may be a substrate having an ion-exchange layer 20a in which at least a portion of the alkali metal ions (excluding potassium ions) are substituted with potassium ions (see FIG. 4). The ion-exchange layer 20a may be, for example, a layer in which at least a portion of the lithium ions and / or sodium ions in the glass material are substituted with potassium ions.

[0055] The ion exchange layer 20a may be formed near at least one surface of the glass substrate 20. The ion exchange layer 20a may be formed near both surfaces of the glass substrate 20.

[0056] The thickness of the ion exchange layer 20a may be determined by the range from the surface of the glass substrate 20 (the surface into which potassium elements have been introduced) where the potassium ion concentration is 5% of the maximum concentration (corresponding to range D in Figure 5). The horizontal axis in Figure 5 indicates the position (depth) in the thickness direction of the glass substrate 20. The vertical axis in Figure 5 indicates the concentration of alkali metal elements in the glass substrate 20. Therefore, Figure 5 shows the relationship between the concentration of alkali metal elements in the glass substrate 20 and the depth of the glass substrate 20. The concentration of alkali metal elements in the thickness direction can be evaluated, for example, by using glow discharge optical emission spectroscopy.

[0057] The concentrations of alkali metal elements shown in Fig. 5 are merely examples. As shown in Fig. 5, the concentration of potassium element in the glass substrate 20 is substantially maximum at the surface of the glass substrate 20 (position "0" on the horizontal axis) and decreases as the depth into the glass substrate 20 increases. On the other hand, the concentration of sodium element in the glass substrate 20 is low at the surface of the glass substrate 20 (position "0" on the horizontal axis) and increases as the depth into the glass substrate 20 increases.

[0058] Such a concentration distribution of alkali metal elements can be achieved by a process of substituting alkali metal ions (excluding potassium ions) in a glass material with potassium ions. The ion exchange of alkali metal ions in a glass material can be performed, for example, by an immersion ion exchange method or an electric field application ion exchange method. The immersion ion exchange method and the electric field application ion exchange method are known as techniques for producing chemically strengthened glass (see Patent Document 2 mentioned above). For example, by contacting a glass material containing sodium and / or lithium with a solution containing potassium ions, at least a portion of the sodium and / or lithium in the glass material can be substituted with potassium.

[0059] The glass substrate 20 may be chemically strengthened glass. Chemically strengthened glass has a so-called compressive stress layer formed by replacing alkali metal ions in the glass material (ion exchange). In this case, the ion exchange layer 20a may correspond to the compressive stress layer of the chemically strengthened glass (see Patent Document 2).

[0060] The thickness of the ion exchange layer 20a may be, for example, 5 μm or more, preferably 8 μm or more, and more preferably 10 μm or more. The upper limit of the thickness of the ion exchange layer 20a is not particularly limited and may be, for example, 200 μm or less. The thicker the ion exchange layer 20a, the greater the amount of potassium in the glass substrate 20, which is thought to prevent a deficiency of potassium in the precursor film 26a described below.

[0061] At the depth of the maximum potassium concentration in the ion exchange layer 20a, the ratio (molar ratio) of the potassium concentration to the sodium concentration may be, for example, 100-50:0-50, preferably 100-80:0-20, and more preferably 100-90:0-10.

[0062] Preferably, the ratio of potassium element among all alkali metal elements may be maximum in at least a part of the depth of the ion exchange layer 20a, in which case the amount of potassium element in the ion exchange layer 20a can be increased.

[0063] 6, step S2 of forming an underlayer 21 and step S3 of forming a first electrode layer 22 are performed. The underlayer 21 is formed on the glass substrate 20. The underlayer 21 can be formed by sputtering, for example.

[0064] The underlayer 21 is made of, for example, SiO ２ , SiO ｘ , MoSi ２ , MoSi ｘ , SiN, SiNx, Al ２ O ３ , Al ｘ O ｙ , Ti, TiO ２ , TiO ｘ, TiN, and TiNx. Here, the positive real numbers x and y may be selected appropriately. These materials may function to adjust the amount of movement of alkali metal elements in the heating step described below. The thickness of the underlayer 21 may be set appropriately to adjust the amount of movement of alkali metal elements in the heating step described below. The thickness of the underlayer 21 may be in the range of, for example, 0.5 to 100 nm, preferably 1 to 50 nm, and more preferably 2 to 30 nm.

[0065] The first electrode layer 22 is formed on the glass substrate 20 or the underlayer 21. When the underlayer 21 is provided, the first electrode layer 22 is formed on the underlayer 21. When the underlayer 21 is not provided, the first electrode layer 22 is formed on the surface of the glass substrate 20.

[0066] The thickness of the first electrode layer 22 may be, for example, 50 nm to 1500 nm, preferably 50 nm to 1200 nm, more preferably 50 nm to 800 nm, and even more preferably 50 nm to 500 nm. From the viewpoint of effectively transferring potassium element in the glass substrate 20 into the photoelectric conversion layer 22 in the heating step described below, it is preferable that the first electrode layer 22 is not too thick.

[0067] The first electrode layer 22 is formed by depositing a material for the first electrode layer 22 on the surface of the glass substrate 20 or the base layer 21 by, for example, sputtering. The material for the first electrode layer 22 is as described above. The sputtering may be a direct current (DC) sputtering method or a radio frequency (RF) sputtering method. Alternatively, the first electrode layer 22 may be formed by a chemical vapor deposition (CVD) method, an atomic layer deposition (ALD) method, or the like instead of sputtering.

[0068] The underlayer 21 and / or the first electrode layer 22 are preferably formed on the surface of the glass substrate 20 on which the ion exchange layer 20a is formed.

[0069] 7, step S4 is performed to form a precursor film 26a on the glass substrate 20. The precursor film 26a is formed on the glass substrate 20, more specifically, on the first electrode layer 22.

[0070] The precursor film 26 a can be formed by, for example, physical vapor deposition (PVD), such as sputtering or evaporation. The evaporation method is a method of forming a film using atoms or the like that are vaporized by heating an evaporation source.

[0071] When forming a CIS-based photoelectric conversion layer 26, step S4 of forming the precursor film 26a includes depositing at least a group I element and a group III element. That is, the precursor film 26a may contain a group I element and a group III element. Preferably, potassium may also be deposited. For example, the precursor film 26a may be formed as a laminate of a film containing a group III element and a film containing a group I element. The group I element may be selected from Ag, Cu, Au, etc. The group III element may be selected from indium, gallium, aluminum, etc. Furthermore, it is preferable that the precursor film 26a additionally contains an alkali metal element such as Li, Na, K, Rb, or Cs, preferably potassium.

[0072] Furthermore, the precursor film 26a may additionally contain tellurium as a Group VI element in addition to selenium and sulfur.

[0073] For example, the precursor film 26 a may be formed as a laminate of a film containing a group I element and a group III element and a film containing a group III element, in which case it is preferable that an alkali metal element, preferably potassium, is contained in one of the films constituting the laminate.

[0074] 7, the precursor film 26a may include a first film 26b containing a group I element and a group III element, a second film 26c containing a group I element and a group III element, and a third film 26c containing a group III element. In this case, it is preferable that at least one of the first film 26b and the second film 26c contains an alkali metal element, preferably potassium.

[0075] On the other hand, when forming a CZTS-based photoelectric conversion layer 26, the precursor layer 26a is formed by depositing at least Cu, Zn, and Sn elements, or by depositing at least Cu, Zn, Sn, Se, and S elements. Preferably, potassium may also be deposited. The precursor layer 26a may be deposited as a thin film of, for example, Cu—Zn—Sn or Cu—Zn—Sn—Se—S. The thin film may contain an alkali metal element, preferably potassium.

[0076] Next, as shown in FIG. 6, step S5 is carried out to heat the glass substrate 20 and the precursor film 26a.

[0077] The inventors of the present application have found that step S5 of heating the glass substrate 20 and the precursor film 26a provides the following advantages: If the glass substrate 20 does not have an ion exchange layer in which at least a portion of the alkali metal ions (excluding potassium ions) are substituted with potassium ions, potassium elements in the precursor film 26a may be substituted with alkali metal ions (excluding potassium ions) in the glass substrate 20 during heating in step S5. This may reduce the amount of potassium elements contained in the photoelectric conversion layer after heating, which may result in a decrease in the photoelectric conversion efficiency of the photoelectric conversion element.

[0078] In this embodiment, the glass substrate 20 has an ion-exchange layer 20a in which at least a portion of the alkali metal ions (excluding potassium ions) have been replaced with potassium ions. That is, the ion-exchange layer 20a of the glass substrate 20 contains a certain amount of potassium as an alkali metal element before heating. In this case, heating the precursor film 26a and the glass substrate 20 can reduce the amount of potassium migrating from the precursor film 26a to the glass substrate 20 and can migrate the potassium in the ion-exchange layer 20a of the glass substrate 20 into the precursor film 26a (photoelectric conversion layer 26). Therefore, it is possible to suppress a deficiency of potassium in the photoelectric conversion layer 26 after heating and maintain or increase the amount of potassium in the photoelectric conversion layer 26. This can suppress a decrease in the photoelectric conversion efficiency of the photoelectric conversion element 10 and improve the photoelectric conversion efficiency.

[0079] Furthermore, sodium elements in the glass substrate 20 can be moved into the precursor film 26a (photoelectric conversion layer 26) by heating the precursor film 26a and the glass substrate 20. This makes it possible to maintain or increase the amount of sodium elements contained in the photoelectric conversion layer 26 after heating.

[0080] From the viewpoint of moving potassium ions in the ion exchange layer 20a of the glass substrate 20 toward the precursor film 26a (photoelectric conversion layer 26), it is considered that the heating temperature in the heating step S5 is better. In the heating step S5, the glass substrate 20 and the precursor film 26a may be heated to, for example, 250°C or higher, preferably 350°C or higher, and more preferably 450°C or higher. The glass substrate 20 and the precursor film 26a may be heated to, for example, an upper limit temperature of 950°C or lower, preferably 850°C or lower, and more preferably 750°C or lower.

[0081] From the viewpoint of suppressing a decrease in the photoelectric conversion efficiency of the manufactured photoelectric conversion element 10, it is preferable that the amount of potassium element in the film (photoelectric conversion layer 26) corresponding to the precursor film 26a after heating in the heating step S5 be equal to or greater than the amount of potassium element in the precursor film 26a before heating. The amount of potassium element in the precursor film 26a after heating can be increased by increasing the concentration of potassium element in the ion exchange layer 20a of the glass substrate 20 or by adjusting the heating temperature and heating time of the glass substrate 20 and the precursor film 26a.

[0082] In the heating step S5, the potassium concentration in the film (photoelectric conversion layer 26) corresponding to the precursor film 26a after heating can be more than twice the potassium concentration in the precursor film 26a before heating. Furthermore, in the heating step S5, the potassium concentration in the film (photoelectric conversion layer 26) corresponding to the precursor film 26a after heating can be more than three times the potassium concentration in the precursor film 26a before heating. Note that the potassium concentration in the photoelectric conversion layer 26 after heating may be, for example, 30 times or less, 20 times or less, or 10 times or less the potassium concentration in the precursor film 26a before heating.

[0083] In this embodiment, the heating step S5 includes heating the glass substrate 20 and the precursor film 26 a and chalcogenizing the material that constitutes the precursor film 26 a. The chalcogenization may include at least one of selenization and sulfurization, and preferably both.

[0084] The precursor film 26 a is chalcogenized to form a chalcogen compound semiconductor, thereby forming a photoelectric conversion layer 26 containing a chalcogen compound semiconductor on the glass substrate 20 .

[0085] When forming the CIS-based photoelectric conversion layer 26, the precursor film 26a is subjected to chalcogenization treatment by heating the precursor film 26a containing at least Group I and Group III elements and the glass substrate 20 in an atmosphere containing Group VI elements. As a result, the precursor film 26a is chalcogenized, and the photoelectric conversion layer 26 is formed.

[0086] In the chalcogenization process, for example, selenization is first performed by vapor-phase selenization. Selenization is performed by heating the precursor layer in an atmosphere of a selenium source gas (e.g., hydrogen selenide or selenium vapor) containing selenium as a Group VI element source. Although not particularly limited, selenization is preferably performed in a heating furnace at a temperature ranging from 250°C to 650°C, preferably from 350°C to 650°C, and more preferably from 450°C to 650°C.

[0087] As a result, the precursor film is converted into a compound (photoelectric conversion layer 26) containing a group I element, a group III element, and selenium. Note that the compound (photoelectric conversion layer 26) containing a group I element, a group III element, and selenium may be formed by a method other than vapor-phase selenization. For example, such a compound can also be formed by solid-phase selenization, vapor deposition, ink application, electrodeposition, or the like.

[0088] Next, the compound containing the Group I element, the Group III element, and selenium is sulfurized. The sulfurization is performed by heating the selenized precursor film and the glass substrate 20 in an atmosphere of a sulfur-containing sulfur source gas (e.g., hydrogen sulfide or sulfur vapor). As a result, the photoelectric conversion layer 26 is converted into a semiconductor compound containing the Group I element, the Group III element, and selenium and sulfur as Group VI elements. The sulfur source gas serves to substitute sulfur for selenium in crystals composed of the Group I element, the Group III element, and selenium, for example, chalcopyrite crystals, on the surface portion of the photoelectric conversion layer 26.

[0089] The sulfurization is preferably carried out in a heating furnace at a temperature in the range of 450° C. to 650° C., for example.

[0090] The chalcogenization converts the precursor film 26 a into the photoelectric conversion layer 26. In addition, as the chalcogenization proceeds, a first buffer layer 27 containing a compound made of a transition metal material such as M0, W, Ti, V, Cr, Nb, or Ta that constitutes the first electrode layer 22 and a chalcogen element such as O, S, or Se is formed between the first electrode layer 22 and the photoelectric conversion layer 26.

[0091] On the other hand, when forming the CZTS-based photoelectric conversion layer 26, the precursor layer 26a containing Cu, Zn, and Sn and the glass substrate 20 are subjected to chalcogenization treatment in a hydrogen sulfide atmosphere and a hydrogen selenide atmosphere at a temperature in the range of, for example, 450° C. to 650° C. In this way, Cu ２ ZnSn(S,Se) ４ Furthermore, by the sulfurization and selenization, a first buffer layer 27 is formed between the first electrode layer 22 and the photoelectric conversion layer 26.

[0092] The heating in step S5 of heating the glass substrate 20 and the precursor film 26a may correspond to the heating performed in the above-mentioned chalcogenization (selenization and / or sulfurization).

[0093] In the above embodiment, both selenization and sulfurization are performed when converting the precursor film 26a into the photoelectric conversion layer 26. However, the present invention is not limited to this, and the precursor film may be converted into the photoelectric conversion layer 26 by any chalcogenization process.

[0094] 9, step S6 of forming a second buffer layer 28 and step S7 of forming a second electrode layer 24 are performed. The second buffer layer 28 is formed by depositing a film on the photoelectric conversion layer 26 by a method such as CBD (chemical bath deposition), sputtering, CVD, or ALD. The material constituting the second buffer layer 28 is as described above.

[0095] The second electrode layer 24 is formed on the second buffer layer 28 by a method such as sputtering, CVD, or ALD. Alternatively, if the second buffer layer 28 is not formed, the second electrode layer 24 is formed directly on the photoelectric conversion layer 26. The material constituting the second electrode layer 24 is as described above.

[0096] Next, step S8 is performed to form the collecting electrode 30. The collecting electrode 30 is formed on the second electrode layer 24. The collecting electrode 30 can be formed by applying, for example, a sputtering method, a CVD method, an ALD method, an AD method, or a vapor deposition method, as well as a printing process such as an inkjet method or a screen printing method.

[0097] The collecting electrode 30 may include a plurality of linear first portions 31 and second portions 32 connected to the plurality of first portions 31. If necessary, wiring 50 is joined to the collecting electrode 30. Here, the collecting electrode 30, the wiring 50, etc. are not essential, and may not be formed if unnecessary.

[0098] Experimental Example 1 Next, Experimental Example 1 will be described. First, aluminosilicate glass including an ion exchange layer in which at least a portion of the sodium ions were substituted with potassium ions was prepared as the glass substrate 20. Specifically, the glass substrate 20 was chemically strengthened aluminosilicate glass. The chemically strengthened aluminosilicate glass is formed by bringing aluminosilicate glass into contact with a solution in which potassium ions are dissolved at high temperature.

[0099] After cleaning the glass substrate 20, the underlayer 21 and the first electrode layer 22 were formed on the glass substrate 20 by sputtering. The material constituting the underlayer 21 was SiO ２ The material forming the first electrode layer 22 was molybdenum.

[0100] Next, a precursor film 26a was formed by sputtering on the first electrode layer 22. The precursor film 26a was formed of a laminate of a CuGaK film 26b, a CuGa film 26c, and an In film 26d. The amount of potassium element in the precursor film 26a was 0.013 μmol / cm ２ It was.

[0101] Next, the glass substrate 20 and the precursor film 26a were reacted (chalcogenized) with hydrogen selenide and hydrogen sulfide at a high temperature of 500°C or higher to obtain the photoelectric conversion layer 26 (heating step S5). The photoelectric conversion layer 26 is mainly composed of Cu(In,Ga)(Se,S). ２ was formed by

[0102] ICP (Inductively Coupled Plasma) analysis was performed on the sample formed up to the photoelectric conversion layer 26. Specifically, a Shimadzu Corporation multichannel type ICP emission spectrometer ICPE-9000 was used. Furthermore, calibration curves were drawn using three types of standard solutions: (1) no alkali (Na, K) added, (2) containing 100 ppb each of Na and K, and (3) containing 200 ppb each of Na and K. The prepared sample was then immersed in a mixed acid of hydrochloric acid and nitric acid, thereby dissolving the first electrode layer 22 and the photoelectric conversion layer 26 entirely in the acid. After diluting this acid solution with ultrapure water, ICP analysis was performed to quantitatively measure the sodium concentration, potassium concentration, and molybdenum concentration.

[0103] Reference Example 1 will now be described. In Reference Example 1, aluminosilicate glass not including an ion exchange layer in which at least a portion of alkali metal ions (excluding potassium ions) were substituted with potassium ions was prepared as glass substrate 20. Under the same conditions as in Experimental Example 1, except that glass substrate 20 did not include an ion exchange layer, base layer 21, first electrode layer 22, and photoelectric conversion layer 26 were formed on glass substrate 20.

[0104] Furthermore, the sample having the photoelectric conversion layer 26 formed thereon was subjected to ICP analysis in the same manner as in Experimental Example 1, to quantitatively measure the sodium concentration, potassium concentration, and molybdenum concentration.

[0105] (Table 1)

[0106] Table 1 shows the sodium concentration, potassium concentration, and molybdenum concentration measured in Experimental Example 1 and Reference Example 1. As described above, the concentration of potassium element in the precursor film 26a before chalcogenization was 0.013 μmol / cm２ Furthermore, sodium element is not added to the precursor film 26a before chalcogenization.

[0107] In Reference Example 1, the sodium concentration after chalcogenization was 0.095 μmol / cm ２ , which is an increase from the concentration before chalcogenization. Therefore, it is considered that the sodium element in the glass substrate 20 has migrated toward the precursor film 26a. On the other hand, the potassium concentration after chalcogenization is 0.007 μmol / cm ２ This indicates that the potassium element contained in the precursor film has migrated into the glass substrate 20.

[0108] In Experimental Example 1, the sodium concentration after chalcogenization was 0.083 μmol / cm ２ , which is an increase from the concentration before chalcogenization. Therefore, it is considered that the sodium element in the glass substrate 20 has migrated toward the precursor film 26a. On the other hand, the potassium concentration after chalcogenization is 0.047 μmol / cm ２ This is a significant increase from the concentration before chalcogenization. Therefore, it is believed that potassium elements in the ion exchange layer 20a of the glass substrate 20 have migrated toward the precursor film 26a (photoelectric conversion layer 26).

[0109] In this way, if the glass substrate 20 has the ion exchange layer 20a in which at least a portion of the alkali metal ions (excluding potassium ions) are substituted with potassium ions, the potassium elements in the ion exchange layer 20a can suppress a deficiency of the potassium elements in the precursor film 26a (photoelectric conversion layer 26) or increase the amount of the potassium elements in the precursor film 26a (photoelectric conversion layer 26).

[0110] In Experimental Example 1, the concentration of potassium element in the photoelectric conversion layer 26 after heating (after chalcogenization) is two to three times or more the concentration of potassium element in the precursor film 26a before heating.

[0111] Furthermore, as shown in Table 1, the total concentration of potassium and sodium elements in Experimental Example 1 is greater than the total concentration of potassium and sodium elements in Reference Example 1. In this way, it is also possible to increase the overall concentration of alkali metal elements in the photoelectric conversion layer 26.

[0112] Experimental Example 2 Next, Experimental Example 2 will be described. First, aluminosilicate glass including an ion exchange layer 20a in which at least a portion of the sodium ions were replaced with potassium ions was prepared as the glass substrate 20. Specifically, the glass substrate 20 was chemically strengthened aluminosilicate glass. The chemically strengthened aluminosilicate glass was formed by bringing aluminosilicate glass into contact with a high-temperature potassium ion molten salt solution. After cleaning the glass substrate 20, an underlayer 21 and a first electrode layer 22 were formed on the glass substrate 20 by sputtering. The material constituting the underlayer 21 was SiO ２ The material forming the first electrode layer 22 was molybdenum.

[0113] Next, a precursor film 26a was formed by sputtering on the first electrode layer 22. The precursor film 26a was formed of a laminate of a CuGaK film 26b, a CuGa film 26c, and an In film 26d. The amount of potassium element in the precursor film 26a was 0.013 μmol / cm ２ It was.

[0114] Next, the glass substrate 20 and the precursor film 26a were reacted (chalcogenized) with hydrogen selenide and hydrogen sulfide at a high temperature of 500°C or higher to obtain the photoelectric conversion layer 26 (heating step S5). The photoelectric conversion layer 26 is mainly composed of Cu(In,Ga)(Se,S). ２ was formed by

[0115] A PL evaluation was carried out on the sample formed up to the photoelectric conversion layer 26. In the PL evaluation, light was irradiated onto the photoelectric conversion layer 26, and light (emission spectrum) generated when excited electrons returned to the ground state was observed.

[0116] After the PL evaluation, a cadmium sulfide layer was formed as the second buffer layer 28 on the surface of the photoelectric conversion layer 26 by a dipping method. Furthermore, an indium tin oxide film was formed as the second electrode layer 24 on the second buffer layer 28 by a sputtering method. The current-voltage characteristics of the photoelectric conversion element thus obtained were measured. In measuring the current-voltage characteristics, a simulated sunlight irradiation device (a solar simulator (model number: WXS-350S-L2MS) manufactured by Wacom Denso Co., Ltd.) was used as the light source, and the light intensity was 1 sun (AM 1.5 G, 100 mW / cm ２ The photoelectric conversion element was irradiated with light of 1 sun, and the output current was measured while changing the bias voltage.

[0117] Reference Example 2 will now be described. In Reference Example 2, aluminosilicate glass not including an ion exchange layer in which at least a portion of alkali metal ions (excluding potassium ions) were substituted with potassium ions was prepared as glass substrate 20. Under the same conditions as in Experimental Example 2, except that glass substrate 20 did not include ion exchange layer 20a, base layer 21, first electrode layer 22, and photoelectric conversion layer 26 were formed on glass substrate 20. PL evaluation was performed using the same procedure as in Experimental Example 2 for a sample formed up to photoelectric conversion layer 26.

[0118] After the PL evaluation, the second buffer layer 28 and the second electrode layer 24 were formed using the same procedures and materials as in Experimental Example 2. The current-voltage characteristics of the photoelectric conversion element thus obtained were measured in the same manner as in Experimental Example 2.

[0119] Fig. 10 is a graph showing the results of PL (photoluminescence) evaluation in Experimental Example 2 and Reference Example 2. In Fig. 10, the horizontal axis represents the wavelength of light, and the vertical axis represents the intensity of the emission spectrum.

[0120] The intensity of the emission spectrum in Experimental Example 2 is higher than that in Reference Example 2. This suggests that there are fewer non-radiative recombination centers in the photoelectric conversion layer 26 in Experimental Example 2. Therefore, it is understood that the photoelectric conversion layer 26 in Experimental Example 2 is likely to be more suitable as a light absorption layer.

[0121] 11 is a graph showing the results of the current-voltage characteristics (IV characteristics) of the photoelectric conversion elements according to Experimental Example 2 and Reference Example 2. In FIG. 11, the horizontal axis represents voltage values, and the vertical axis represents current values. Referring to FIG. 11, the current-voltage curve of the photoelectric conversion element according to Experimental Example 2 is generally higher than the current-voltage curve of the photoelectric conversion element according to Reference Example 2. Therefore, it can be seen that the output of the photoelectric conversion element according to Experimental Example 2 is higher, and the current-voltage characteristics are improved.

[0122] [Photoelectric Conversion Module] Next, a photoelectric conversion module according to an embodiment will be described with reference to Fig. 12. Fig. 12 is a schematic plan view of the photoelectric conversion module according to an embodiment.

[0123] The photoelectric conversion module 100 may include one or more photoelectric conversion elements 10. Fig. 12 shows a photoelectric conversion module 100 including a plurality of photoelectric conversion elements 10. The one or more photoelectric conversion elements 10 may be sealed with, for example, a sealing material. The configuration of each photoelectric conversion element 10 is as described in the above embodiment.

[0124] When the photoelectric conversion module 100 includes a plurality of photoelectric conversion elements 10, the plurality of photoelectric conversion elements 10 may be arranged in at least one direction, preferably in a lattice pattern. In this case, the plurality of photoelectric conversion elements 10 may be electrically connected to each other in series and / or parallel.

[0125] In the example shown in Fig. 12, adjacent photoelectric conversion elements 10 arranged in one direction partially overlap each other. Specifically, as shown in Fig. 12, a photoelectric conversion element 10 is arranged so as to cover a part of another photoelectric conversion element 10 adjacent thereto.

[0126] Adjacent photoelectric conversion elements 10 may be electrically connected to each other by a connector. In this case, the connector may extend across the adjacent photoelectric conversion elements 10.

[0127] Instead of the embodiment shown in FIG. 12, the photoelectric conversion elements 10 adjacent to each other may be arranged with a gap therebetween.

[0128] [Satellite and Paddle for Satellite] Next, a satellite equipped with a photoelectric conversion module and a paddle for the satellite will be described. Fig. 13 is a schematic perspective view of a satellite equipped with a photoelectric conversion module. The satellite 900 may have a base 910 and a paddle 920. The base 910 may include equipment (not shown) necessary for controlling the satellite 900. An antenna 940 may be attached to the base 910.

[0129] The paddle 920 may include the above-described photoelectric conversion module 100. The paddle 920 including the photoelectric conversion module 100 can be used as a power source for operating various devices provided on the base 910. In this way, the photoelectric conversion module 100 can be applied to paddles for artificial satellites.

[0130] The paddle 920 may have a connecting portion 922 and a hinge portion 924. The connecting portion 922 corresponds to the portion that connects the paddle 920 to the base portion 910.

[0131] The hinge portion 924 extends in one direction, allowing the paddle 920 to be folded around the hinge portion 924 as a rotation axis. Each paddle 920 may have at least one, and preferably a plurality of, hinge portions 924. This allows the paddle 920 equipped with the photovoltaic conversion module 100 to be foldable into a small size. When the satellite 900 is launched, the paddle 920 may be in a folded state. The paddle 920 may be unfolded when receiving sunlight to generate power.

[0132] 13 , the paddle 920 may have a cylindrical shape formed by being wound. This allows the paddle 920 to assume a generally flat, deployed state by rotating the wound portion. When the satellite 900 is launched, the paddle 920 may maintain a generally cylindrical shape. The paddle 920 may be deployed to a generally flat state when receiving sunlight and generating power.

[0133] As described above, the contents of the present invention have been disclosed through the embodiments, but the descriptions and drawings that form part of this disclosure should not be understood to limit the present invention. Various alternative embodiments, examples, and operating techniques will become apparent to those skilled in the art from this disclosure. Therefore, the technical scope of the present invention is defined only by the inventive features of the claims that can be reasonably understood from the above description.

[0134] This application claims priority based on Japanese Patent Application No. 2024-048497, filed on March 25, 2024, the entire contents of which are incorporated herein by reference.

Claims

1. A method for manufacturing a photoelectric conversion element, comprising the steps of: preparing a glass substrate having an ion exchange layer in which at least a portion of alkali metal ions (excluding potassium ions) are substituted with potassium ions; forming a precursor film on the glass substrate; and heating the glass substrate and the precursor film.

2. A method for manufacturing a photoelectric conversion element as described in claim 1, wherein in the heating step, the amount of potassium element in the film corresponding to the precursor film after heating is the same as or greater than the amount of potassium element in the precursor film before heating.

3. A method for manufacturing a photoelectric conversion element as described in claim 1 or 2, wherein in the heating step, the concentration of potassium element in the film corresponding to the precursor film after heating is at least twice the concentration of potassium element in the precursor film before heating.

4. A method for manufacturing a photoelectric conversion element according to any one of claims 1 to 3, wherein in the heating step, the concentration of potassium element in the film corresponding to the precursor film after heating is at least three times the concentration of potassium element in the precursor film before heating.

5. The method for producing a photoelectric conversion element according to any one of claims 1 to 4, wherein the ratio of potassium element among all alkali metal elements is maximum in at least a portion of the depth of the ion exchange layer.

6. The method for producing a photoelectric conversion element according to any one of claims 1 to 5, wherein the ion exchange layer has a thickness of 5 μm or more.

7. The method for manufacturing a photoelectric conversion element according to any one of claims 1 to 6, wherein the glass substrate is chemically strengthened glass.

8. The method for manufacturing a photoelectric conversion element according to any one of claims 1 to 7, wherein the heating step includes heating the glass substrate and the precursor film at 250°C or higher.

9. A method for manufacturing a photoelectric conversion element according to any one of claims 1 to 8, wherein the step of forming the precursor film includes depositing a film of at least a group I element and a group III element, depositing a film of at least Cu, Zn, and Sn elements, or depositing a film of at least Cu, Zn, Sn, Se, and S elements.

10. The method for manufacturing a photoelectric conversion element according to any one of claims 1 to 9, wherein the step of forming the precursor film includes depositing a film containing elemental potassium.

11. A method for manufacturing a photoelectric conversion element according to any one of claims 1 to 10, wherein the heating step includes heating the glass substrate and the precursor film and chalcogenizing the material that constitutes the precursor film.

12. A photoelectric conversion element comprising: a glass substrate having an ion exchange layer in which at least a portion of alkali metal ions (excluding potassium ions) are substituted with potassium ions; and a photoelectric conversion layer containing a chalcogen compound semiconductor formed on the glass substrate.

13. The photoelectric conversion element according to claim 12, wherein the ratio of potassium element to all alkali metal elements is maximum in at least a portion of the depth of said ion exchange layer.

14. The photoelectric conversion element according to claim 12 or 13, wherein the ion exchange layer has a thickness of 5 μm or more.

15. The photoelectric conversion element according to any one of claims 12 to 14, wherein the glass substrate is chemically strengthened glass.

16. The photoelectric conversion element according to any one of claims 12 to 15, wherein the photoelectric conversion layer contains a chalcogen compound semiconductor.

17. The photoelectric conversion element according to any one of claims 12 to 16, wherein the photoelectric conversion layer contains potassium.

18. A photoelectric conversion module comprising a plurality of photoelectric conversion elements according to any one of claims 12 to 17.

19. A paddle comprising the photoelectric conversion module of claim 18.

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