Perovskite solar cell and method for manufacturing the same

Abstract

The present invention provides a solar cell comprising a light absorption layer containing a perovskite compound and an electron transport layer provided on one surface of the light absorption layer, wherein the electron transport layer comprises a first electron transport layer provided on one surface of the light absorption layer and a second electron transport layer provided on the first electron transport layer, the first electron transport layer comprises an inorganic metal nitride, and the second electron transport layer comprises an inorganic metal oxynitride, and a method for manufacturing the same.

Description

Technical Field

[0001] The present invention relates to a perovskite solar cell and a manufacturing method thereof, and more specifically to an electron transport layer.

Background Art

[0002] A perovskite solar cell includes a light absorption layer containing a perovskite compound, an electron transport layer provided on one surface of the light absorption layer, and a hole transport layer provided on the other surface of the light absorption layer.

[0003] Conventionally, as the electron transport layer, a structure in which an organic layer of C60 and a metal oxide layer are laminated in sequence has been used. However, in such a structure, there is a problem that the efficiency of the solar cell is reduced because the metal oxide layer permeates the organic layer of C60 and oxidizes the perovskite compound constituting the light absorption layer.

Summary of the Invention

Problems to be Solved by the Invention

[0004] The present invention has been devised to solve the above-described conventional problems, and an object of the present invention is to provide a solar cell including an electron transport layer capable of preventing oxidation of a perovskite compound constituting a light absorption layer and a manufacturing method thereof.

Means for Solving the Problems

[0005] To achieve the above object, the present invention includes a light absorption layer containing a perovskite compound and an electron transport layer provided on one surface of the light absorption layer, the electron transport layer including a first electron transport layer provided on one surface of the light absorption layer and a second electron transport layer provided on the first electron transport layer, the first electron transport layer including an inorganic metal nitride, and the second electron transport layer including an inorganic metal oxynitride or the first electron transport layer including an inorganic metal sulfide and the second electron transport layer including an inorganic metal sulfoxide, and provides a solar cell.

[0006] The present invention also provides a solar cell comprising a light absorption layer containing a perovskite compound and an electron transport layer provided on one surface of the light absorption layer, wherein the first electron transport layer comprises a first electron transport layer provided on one surface of the light absorption layer and a third electron transport layer provided on the first electron transport layer, the first electron transport layer comprises an inorganic metal nitride or an inorganic metal sulfide, and the third electron transport layer comprises an inorganic metal oxynitride.

[0007] The present invention also provides a method for manufacturing a solar cell, comprising the steps of forming a light absorption layer containing a perovskite compound and forming an electron transport layer on one surface of the light absorption layer, wherein the step of forming the electron transport layer comprises forming an electron transport precursor layer containing an inorganic metal nitride or an inorganic metal sulfide, and subjecting the electron transport precursor layer to oxygen plasma treatment to form a first electron transport layer containing the inorganic metal nitride or the inorganic metal sulfide and a second electron transport layer containing an inorganic metal oxynitride or an inorganic metal sulfoxide.

[0008] The present invention also provides a method for manufacturing a solar cell, comprising the steps of forming a light absorption layer containing a perovskite compound and forming an electron absorption layer on one surface of the light absorption layer, wherein the step of forming the electron transport layer comprises forming an electron transport precursor layer containing an inorganic metal nitride or an inorganic metal sulfide, and subjecting the electron transport precursor layer to oxygen plasma treatment to form a first electron transport layer containing the inorganic metal nitride or the inorganic metal sulfide and a third electron transport layer containing an inorganic metal oxide.

Advantages of the Invention

[0009] According to the present invention as described above, the following effects can be achieved.

[0010] According to an embodiment of the present invention, an electron transport precursor layer made of an inorganic nitride, particularly an oxygen-free inorganic nitride, specifically SnN or ZnN, is formed on the light absorption layer, or an electron transport precursor layer made of an inorganic sulfide, particularly an oxygen-free inorganic sulfide, specifically SnS, SnS2 or ZnS, is formed. Thereby, since the inorganic nitride such as SnN or ZnN, or the inorganic sulfide such as SnS, SnS2 or ZnS does not contain oxygen, oxidation of the perovskite compound constituting the light absorption layer can be prevented during the process of forming the electron transport precursor layer.

[0011] According to an embodiment of the present invention, the first electron transport layer containing the inorganic nitride or inorganic sulfide can function as a damage prevention film or a barrier film for the lower film thereof. Further, the second electron transport layer containing an inorganic metal oxynitride or an inorganic metaloxysulfide can function as a damage prevention film or a barrier film for the lower film thereof.

[0012] According to an embodiment of the present invention, a first electron transport layer made of an inorganic nitride, particularly an oxygen-free inorganic nitride, specifically SnN or ZnN, is formed on the light absorption layer, or a first electron transport layer made of an inorganic sulfide, particularly an oxygen-free inorganic sulfide, specifically SnS, SnS2 or ZnS, is formed. Thereby, since the inorganic nitride such as SnN or ZnN, or the inorganic sulfide such as SnS, SnS2 or ZnS does not contain oxygen, oxidation of the perovskite compound constituting the light absorption layer provided under the first electron transport layer can be prevented.

[0013] According to an embodiment of the present invention, by forming the thickness of the second electron transport layer 52 to be thicker than the thickness of the first electron transport layer, the electrical conductivity characteristics can be improved.

Brief Description of the Drawings

[0014]

Figure 1A

Figure 1B

Figure 1C

Figure 1D

Figure 2A

Figure 2B

Figure 2C

Figure 2D

Figure 2E

Figure 3A

Figure 3B

Figure 3C

Figure 3D

Figure 3E

Figure 3F

Figure 3G

Figure 4A

Figure 4B

Figure 4C

Figure 4D

Figure 4E

Figure 4F

Figure 4G

Figure 4H

Figure 5A

Figure 5B

Figure 5C

Figure 5D

Mode for Carrying Out the Invention

[0015] The advantages, features, and the methods for achieving them of the present invention will become apparent by referring to the embodiments described in detail below together with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but can be embodied in various different forms, and these embodiments are merely provided to make the disclosure of the present invention complete and to fully inform those with ordinary knowledge in the technical field to which the present invention pertains of the scope of the invention. The present invention is only defined by the scope of the claims.

[0016] The shapes, sizes, ratios, angles, numbers, etc. disclosed in the figures for explaining the embodiments of the present invention are exemplary, and the present invention is not limited to the matters shown in the figures. Throughout the specification, the same reference numerals refer to the same components. In the description of the present invention, when it is determined that a specific description of related known technologies may unnecessarily obscure the gist of the present invention, the detailed description thereof is omitted. When terms such as "including", "having", and "consisting of" are used in the present invention, other parts may be added unless "only" is used. When a component is expressed in the singular, it includes the case of including a plurality unless otherwise explicitly stated.

[0017] In interpreting a component, even if there is no separate explicit description of the error range, it is interpreted as including the error range.

[0018] In the case of an explanation of the positional relationship, for example, when the positional relationship between two parts is explained by "on ~", "above ~", "below ~", "beside ~", etc., unless the expressions "immediately" or "directly" are used, one or more other parts can also be located between the two parts.

[0019] In the case of an explanation of the time relationship, for example, when the temporal precedence relationship is explained by "after ~", "subsequent to ~", "next ~", "before ~", etc., unless the expressions "immediately" or "directly" are used, the case of not being continuous can also be included.

[0020] First, second, etc. are used to explain various components, but these components are not limited by these terms. These terms are merely used to distinguish one component from another. Therefore, the first component mentioned below may also be the second component within the technical idea of the present invention.

[0021] The features of each of several embodiments of the present invention can be partially or wholly combined or combined with each other, enabling various technical linkages and drives, and each embodiment can be implemented independently of each other or implemented together in an associated relationship.

[0022] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings.

[0023] Figures 1A to 1D are manufacturing process diagrams of a solar cell according to an embodiment of the present invention.

[0024] First, as shown in Figure 1A, a first electrode 20 is formed on a substrate 10, a hole transport layer 30 is formed on the first electrode 20, and a light absorption layer 40 is formed on the hole transport layer 30.

[0025] The substrate 10 can be made of a material known in the art such as glass or plastic.

[0026] The first electrode 20 can be made of a conductive oxide such as ITO, but is not necessarily limited thereto. The first electrode 20 can be formed by a deposition process such as ALD (Atomic Layer Deposition).

[0027] The positive hole transport layer 30 can comprise various P-type organic substances known in the art such as Spiro-MeO-TAD, Spiro-TTB, polyaniline, polypyrrole, poly-3,4-ethylenedioxythiophene-polystyrene sulfonate (PEDOT-PSS), or poly-[bis(4-phenyl)(2,4,6-trimethylphenyl)amine] (PTAA), poly(3-hexylthiophene-2,5-diyl) (P3HT), etc., various P-type metal oxides known in the art such as Ni oxide, Mo oxide, or V oxide, W oxide, Cu oxide, etc., and other various P-type organic or inorganic substances known in the art. The positive hole transport layer 30 can be formed by a vapor deposition process such as CVD (Chemical Vapor Deposition) or ALD (Atomic Layer Deposition).

[0028] The light absorption layer 40 is made of a perovskite compound.

[0029] The perovskite compound can be obtained through a process of reacting at least one compound selected from an amine-based compound and an amidine-based compound, an organometallic compound containing a divalent cation, and at least one hydrogen halide through a CVD (Chemical Vapor Deposition) or ALD (Atomic Layer Deposition) process to deposit and form a compound of ABX3.

[0030] In the ABX3, the A can consist of a monovalent organic cation of the amine-based compound, can consist of a monovalent organic cation of the amidine-based compound, or can contain a monovalent organic cation of the amine-based compound and a monovalent organic cation of the amidine-based compound. The A can have a structure in which a monovalent organic cation of the amine-based compound is contained in an x ratio and a monovalent organic cation of the amidine-based compound is contained in a y ratio. Here, x and y are each greater than 0, and x + y = 1.

[0031] In the ABX3, the B consists of the divalent cation.

[0032] In the ABX3, the X consists of at least one halogen compound.

[0033] The amine compound can be selected from the group consisting of methylamine, ethylamine, and phenethylamine.

[0034] The amidine compound can consist of formamidine.

[0035] The organometallic compound containing the divalent cation can contain a metal selected from the group consisting of Pb, Sn, Ge, Sb, Bi, and Ba.

[0036] Specifically, the organometallic compound containing the divalent cation has the following chemical formula 1:

[0037]

Chemical formula

[0038] (wherein, R 1 ~R 12 are each independently hydrogen or an alkyl group, and X is selected from the group consisting of Pb, Sn, Ge, Sb, Bi, and Ba) and can consist of the represented compound.

[0039] Alternatively, the organometallic compound containing the divalent cation can be selected from the group consisting of Pb(CH3)4, Pb(C2H5)4, Pb(SCN)2, (C2H5)3PbOCH2C(CH3)3, Pb(C 11 H 19 O2)2, Pb((CH3)3C-COCHCO-C(CH3)3)2, Pb((C6H5)2PCH2P(C6H5)2)2, Pb(N(CH3)2C(CH3)2OH)2, and C 12 H 28 N2O2Pb.

[0040] Depending on the type of the organometallic compound containing the divalent cation, the light absorption rate, band gap, carrier mobility, and material stability of the finally obtained perovskite compound can be controlled.

[0041] The hydrogen halide can be selected from the group consisting of HI, HBr, Hf, and HCl. The band gap of the finally obtained perovskite compound can be adjusted according to the type of the hydrogen halide.

[0042] The amine compound, the amidine compound, the organometallic compound containing the divalent cation, and the hydrogen halide are composed of substances that vaporize at a temperature in the range of normal temperature to 200°C, preferably substances that vaporize at a temperature in the range of 50°C to 150°C. Thereby, the process of manufacturing the ABX3 compound can be carried out through a chemical vapor deposition (CVD) process or atomic layer deposition (ALD) at a temperature of 200°C or lower, preferably 150°C or lower, and the decomposition of the organic matter in the finally obtained ABX3 compound during the CVD or ALD process can be prevented. On the other hand, it is also possible to apply plasma when performing the CVD or ALD process.

[0043] According to another embodiment of the present invention, the perovskite compound can be obtained by reacting at least one compound selected from an amine compound and an amidine compound, at least one alkali metal compound, an organometallic compound containing a divalent cation, and a hydrogen halide through a CVD (Chemical Vapor Deposition) or ALD (Atomic Layer Deposition) process to deposit and form a CABX3 compound.

[0044] In the CABX3, A can consist of a monovalent organic cation of the amine compound, can consist of a monovalent organic cation of the amidine compound, or can include a monovalent organic cation of the amine compound and a monovalent organic cation of the amidine compound.

[0045] In the CABX3, C can consist of at least one of the alkali metals.

[0046] CA can have a structure in which a monovalent organic cation of the amine compound is contained at a ratio of x, a monovalent organic cation of the amidine compound is contained at a ratio of y, and a monovalent cation of the alkali metal is contained at a ratio of z. Here, x, y, and z are each greater than 0, and x + y + z = 1.

[0047] In the CABX3, B consists of the divalent cation, and X consists of at least one halogen compound.

[0048] Since the amine compound, the amidine compound, the organometallic compound containing the divalent cation, and the hydrogen halide are the same as those described above, repeated explanations will be omitted.

[0049] The alkali metal compound has the following Chemical Formula 2:

[0050]

Chemical Formula

[0051] (In the formula, R 1 ~R 6 are each independently hydrogen or an alkyl group, and Y is an alkali metal) and can consist of a compound represented thereby.

[0052] According to another embodiment of the present invention, as follows, by adding at least one alkali metal compound to the reactants, it is possible to compensate for the instability of monovalent organic cations that are vulnerable to moisture, heat, and plasma.

[0053] Next, as can be seen from FIG. 1B, an electron transport precursor layer 50a is formed on the light absorption layer 40.

[0054] The electron transport precursor layer 50a can be made of an inorganic nitride, particularly an inorganic nitride that does not contain oxygen. Specifically, the electron transport precursor layer 50a can be made of SnN or ZnN.

[0055] The electron transport precursor layer 50a can be made of an inorganic sulfide, particularly an inorganic sulfide that does not contain oxygen. Specifically, the electron transport precursor layer 50a can be made of SnS, SnS2, or ZnS.

[0056] Inorganic nitrides such as SnN or ZnN can be formed by a deposition process such as CVD or ALD. Since inorganic nitrides such as SnN or ZnN do not contain oxygen, oxidation of the perovskite compound constituting the light absorption layer 40 can be prevented during the process of forming the electron transport precursor layer 50a.

[0057] Inorganic sulfides such as SnS, SnS2, or ZnS can be formed by a deposition process such as CVD or ALD. Since inorganic sulfides such as SnS, SnS2, or ZnS do not contain oxygen, oxidation of the perovskite compound constituting the light absorption layer 40 can be prevented during the process of forming the electron transport precursor layer 50a.

[0058] Next, as can be seen from FIG. 1C, an oxygen plasma treatment is performed on the electron transport precursor layer 50a.

[0059] Then, oxygen is introduced into the inorganic metal nitrides such as SnN and ZnN, and the electron transport precursor layer 50a can be changed into an electron transport layer 50 including a first electron transport layer 51, a second electron transport layer 52, and a third electron transport layer 53.

[0060] Alternatively, oxygen is introduced into the inorganic metal sulfides such as SnS, SnS2, and ZnS, and the electron transport precursor layer 50a can be changed into an electron transport layer 50 including a first electron transport layer 51, a second electron transport layer 52, and a third electron transport layer 53.

[0061] The first electron transport layer 51 is a layer in contact with the light absorption layer 40 and is made of the same material as the inorganic metal nitride or inorganic metal sulfide that constitutes the electron transport precursor layer 50a without the introduction of oxygen. Therefore, the first electron transport layer 51 can be made of an oxygen-free inorganic metal nitride, specifically SnN or ZnN, or an oxygen-free inorganic metal sulfide, specifically SnS, SnS2, or ZnS.

[0062] Since the inorganic nitrides such as SnN and ZnN and the inorganic sulfides such as SnS, SnS2, and ZnS do not contain oxygen, oxidation of the perovskite compound constituting the light absorption layer provided under the first electron transport layer 51 can be prevented. Therefore, the first electron transport layer 51 containing the inorganic nitride or inorganic sulfide can function as a damage prevention film or a barrier film for the lower layer film.

[0063] The second electron transport layer 52 is a layer formed on the first electron transport layer 51 while being in contact with the first electron transport layer 51, and is a layer in which oxygen is partially introduced into the inorganic metal nitride or inorganic metal sulfide that constitutes the electron transport precursor layer 50a. Therefore, the second electron transport layer 52 can be made of an inorganic metal oxynitride, specifically SnON or ZnON, or an inorganic metaloxysulfide, specifically SnOS or ZnOS. The second electron transport layer 52 containing the inorganic metal oxynitride or inorganic metaloxysulfide can function as a damage prevention film or a barrier film for the lower layer film.

[0064] The third electron transport layer 53 is a layer formed on the second electron transport layer 52 in contact with the second electron transport layer 52, in which oxygen is introduced into the inorganic metal nitride constituting the electron transport precursor layer 50a and nitrogen is replaced by oxygen, or oxygen is introduced into the inorganic metal sulfide constituting the electron transport precursor layer 50a and sulfur is replaced by oxygen. Therefore, the third electron transport layer 53 can be made of an inorganic metal oxide, specifically SnO or ZnO.

[0065] Since the first electron transport layer 51 is made of an oxygen-free inorganic metal nitride or inorganic metal sulfide, specifically SnN, ZnN, SnS, SnS2 or ZnS, it has the advantage of preventing the oxidation of the perovskite compound constituting the light absorption layer 40 provided thereunder, but has the disadvantage of poor electrical conductivity characteristics.

[0066] In contrast, since the second electron transport layer 52 is made of an inorganic metal oxynitride or inorganic metaloxysulfide, specifically SnON, ZnON, SnOS or ZnOS, it has excellent electrical conductivity characteristics compared to the first electron transport layer 51. Therefore, in order to improve the electrical conductivity characteristics, the thickness (t2) of the second electron transport layer 52 is preferably formed thicker than the thickness (t1) of the first electron transport layer 51.

[0067] In some cases, the second electron transport layer 52 may not be formed in the process of FIG. 1C. Specifically, by performing oxygen plasma treatment on the electron transport precursor layer 50a, instead of forming the second electron transport layer 52 on the upper surface of the first electron transport layer 51 which is the same as the electron transport precursor layer 50a, the third electron transport layer 53 can be directly formed on the upper surface of the first electron transport layer 51.

[0068] As an example, a third electron transport layer 53 made of SnO or ZnO can be directly formed on the upper surface of the first electron transport layer 51 containing an inorganic metal nitride such as SnN or ZnN, and a third electron transport layer 53 made of SnO or ZnO can also be directly formed on the upper surface of the first electron transport layer 51 containing an inorganic metal sulfide such as SnS, SnS2 or ZnS. In this case, the thickness of the third electron transport layer 53 is greater than the thickness of the first electron transport layer 51.

[0069] Next, as can be seen from FIG. 1D, a transparent conductive layer 60 is formed on the electron transport layer 50, and a second electrode 70 is formed on the transparent conductive layer 60.

[0070] The transparent conductive layer 60 can include a substance having electron transport characteristics. The transparent conductive layer 60 can include ITO or IZO, but is not necessarily limited thereto. The transparent conductive layer 60 can be formed by a vapor deposition process such as ALD.

[0071] The second electrode 70 can be made of a metal substance such as Ag. The second electrode 70 can be patterned in a predetermined form so that sunlight can enter the inside of the battery.

[0072] FIGS. 2A to 2E are manufacturing process diagrams of a solar cell according to another embodiment of the present invention.

[0073] First, as can be seen from FIG. 2A, the first electrode 20 is formed on the substrate 10, a hole transport layer 30 is formed on the first electrode 20, and a light absorption layer 40 is formed on the hole transport layer 30.

[0074] The specific configurations of the substrate 10, the first electrode 20, the hole transport layer 30, and the light absorption layer 40 are the same as those in the above-described embodiments, and thus repeated description will be omitted.

[0075] Next, as can be seen from FIG. 2B, an electron transport precursor layer 50a is formed on the light absorption layer 40.

[0076] Since the specific configuration of the electron transport precursor layer 50a is the same as that of the foregoing embodiments, repeated description will be omitted.

[0077] Next, as can be seen from FIG. 2C, an oxygen plasma treatment is performed on the electron transport precursor layer 50a.

[0078] Then, oxygen is introduced into an inorganic metal nitride such as SnN or ZnN, and the electron transport precursor layer 50a can be changed into a first electron transport layer 51 and a second electron transport layer 52.

[0079] Alternatively, oxygen can be introduced into an inorganic metal sulfide such as SnS, SnS2 or ZnS to change the electron transport precursor layer 50a into a first electron transport layer 51 and a second electron transport layer 52.

[0080] The first electron transport layer 51 is a layer in contact with the light absorption layer 40, and is made of the same material as the inorganic metal nitride or inorganic metal sulfide that constitutes the electron transport precursor layer 50a without oxygen being introduced. Therefore, the first electron transport layer 51 can be made of an oxygen-free inorganic metal nitride, specifically SnN or ZnN, or an oxygen-free inorganic metal sulfide, specifically SnS, SnS2 or ZnS.

[0081] The second electron transport layer 52 is a layer formed on the first electron transport layer 51, and is a layer in which oxygen is partially introduced into the inorganic metal nitride or inorganic metal sulfide that constitutes the electron transport precursor layer 50a. Therefore, the second electron transport layer 52 can be made of an inorganic metal oxynitride, specifically SnON or ZnON, or an inorganic metaloxysulfide, specifically SnOS or ZnOS.

[0082] Similar to the above-described embodiments, it is preferable that the thickness (t2) of the second electron transport layer 52 is formed thicker than the thickness (t1) of the first electron transport layer 51.

[0083] In the above-described step of FIG. 1C, the third electron transport layer 53 was further formed on the second electron transport layer 52 by subjecting the electron transport precursor layer 50a to oxygen plasma treatment. However, depending on the process conditions, even if oxygen is introduced into the inorganic metal nitride or inorganic metal sulfide constituting the electron transport precursor layer 50a, nitrogen or sulfur may not be completely replaced by oxygen, so that the third electron transport layer 53 may not be formed.

[0084] Next, as can be seen from FIG. 2D, a third electron transport layer 53 is formed on the second electron transport layer 52, and an electron transport layer 50 including the first electron transport layer 51, the second electron transport layer 52, and the third electron transport layer 53 is formed.

[0085] The third electron transport layer 53 can be made of an inorganic metal oxide, specifically SnO or ZnO. The third electron transport layer 53 can be formed by a vapor deposition process such as ALD.

[0086] Here, the thickness (t3) of the third electron transport layer 53 is preferably formed thicker than the thickness (t1) of the first electron transport layer 51 in order to improve the electrical conductivity characteristics. Also, the thickness (t3) of the third electron transport layer 53 can be formed thicker than the thickness (t2) of the second electron transport layer 52.

[0087] In some cases, the above-described step of FIG. 2C is omitted, and the step of FIG. 2D is performed after the above-described step of FIG. 2B, whereby the third electron transport layer 53 made of an inorganic metal oxide, specifically SnO or ZnO, is formed on the upper surface of the first electron transport layer 51 made of the electron transport precursor layer 50a.

[0088] Next, as can be seen from FIG. 2E, a transparent conductive layer 60 is formed on the electron transport layer 50, and a second electrode 70 is formed on the transparent conductive layer 60.

[0089] Since the specific configurations of the transparent conductive layer 60 and the second electrode 70 are the same as those in the above-described embodiments, repeated description will be omitted.

[0090] In the above embodiment, the state where the hole transport layer 30 is formed on the lower surface of the light absorption layer 40 and the electron transport layer 50 is formed on the upper surface of the light absorption layer 40 is disclosed. However, it is not necessarily limited thereto. The hole transport layer 30 can also be formed on the upper surface of the light absorption layer 40, and the electron transport layer 50 can be formed on the lower surface of the light absorption layer 40. The same applies to the following embodiments.

[0091] Figs. 3A to 3G are manufacturing process diagrams of a solar cell according to another embodiment of the present invention, and relate to a tandem solar cell of a perovskite solar cell and a crystalline solar cell.

[0092] First, as can be seen from Fig. 3A, the crystalline solar cell 100 is manufactured.

[0093] The crystalline solar cell 100 can be manufactured by a process of etching one surface and the other surface of a semiconductor substrate 110 such as a wafer to form an uneven structure, doping a predetermined dopant on one surface of the semiconductor substrate 110 to form a first semiconductor layer 120, and doping a predetermined dopant on the other surface of the semiconductor substrate 110 to form a second semiconductor layer 130.

[0094] By forming one surface and the other surface of the semiconductor substrate 110 into an uneven structure, the first semiconductor layer 120 and the second semiconductor layer 130 each have a shape corresponding to the uneven structure.

[0095] On the other hand, although the figure shows the state where both one surface and the other surface of the semiconductor substrate 110 are formed into an uneven structure, it is not necessarily limited thereto. Either one of one surface and the other surface of the semiconductor substrate 110 can be formed into an uneven structure, and the other one can be formed into a flat structure. In some cases, both one surface and the other surface of the semiconductor substrate 110 can be formed into a flat structure.

[0096] The semiconductor substrate 110 can be made of a P-type or N-type wafer. The first semiconductor layer 120 can be doped with a dopant having a polarity different from that of the semiconductor substrate 110, and the second semiconductor layer 130 can be doped with a dopant having the same polarity as the semiconductor substrate 110. As an example, the semiconductor substrate 110 can be made of a P-type wafer, the first semiconductor layer 120 can be doped with an N-type dopant, and the second semiconductor layer 130 can be doped with a P-type dopant to form a P+ layer.

[0097] Next, as can be seen from FIG. 3B, a buffer layer 200 is formed on the upper surface of the crystalline solar cell 100.

[0098] The buffer layer 200 is formed on the first semiconductor layer 120. Since the first semiconductor layer 120 is formed in an uneven structure, the buffer layer 200 also has an uneven structure.

[0099] The buffer layer 200 is provided between the crystalline solar cell 100 and a perovskite solar cell 300 to be described later, so that the solar cell according to an embodiment of the present invention has a tandem solar cell structure through a tunnel junction.

[0100] The buffer layer 200 is preferably made of a material that allows long-wavelength light transmitted through the perovskite solar cell to be incident on the crystalline solar cell 100 without loss. As an example, the buffer layer 200 can be made of a transparent conductive oxide, a carbonaceous conductive material, a metallic material, or a conductive polymer, and in some cases, the material can be doped with an n-type or p-type dopant.

[0101] Next, as can be seen from FIG. 3C, a hole transport layer 30 is formed on the buffer layer 200, and a light absorption layer 40 is formed on the hole transport layer 30.

[0102] The specific configurations of the hole transport layer 30 and the light absorption layer 40 are the same as those in the above-described embodiments, and thus repeated descriptions will be omitted.

[0103] Next, as can be seen from FIG. 3D, an electron transport precursor layer 50a is formed on the light absorption layer 40.

[0104] The specific configuration of the electron transport precursor layer 50a is the same as that in the above-described embodiments, and thus repeated descriptions will be omitted.

[0105] Next, as can be seen from FIG. 3E, oxygen plasma treatment is performed on the electron transport precursor layer 50a.

[0106] Then, oxygen is introduced into an inorganic metal nitride such as SnN or ZnN or an inorganic metal sulfide such as SnS2 or ZnS, and the electron transport precursor layer 50a can be changed into an electron transport layer 50 including a first electron transport layer 51, a second electron transport layer 52, and a third electron transport layer 53.

[0107] The specific configuration of the electron transport layer 50 including the first electron transport layer 51, the second electron transport layer 52, and the third electron transport layer 53 is the same as that in FIG. 1C described above, and thus repeated descriptions will be omitted.

[0108] Next, as can be seen from FIG. 3F, a transparent conductive layer 60 is formed on the electron transport layer 50.

[0109] The specific configuration of the transparent conductive layer 60 is the same as that in the foregoing embodiments, and thus repeated descriptions will be omitted.

[0110] Next, as can be seen from FIG. 3G, a first electrode 20 is formed on the lower surface of the crystalline solar cell 100, and a second electrode 70 is formed on the upper surface of the transparent conductive layer 60.

[0111] Since the second electrode 70 is formed on the incident surface on which sunlight is incident, it is patterned in a predetermined form. Since the first electrode 20 is also patterned in a predetermined form, the reflected light of sunlight can be configured to enter the inside of the solar cell, but it is not necessarily limited to this.

[0112] The first electrode 20 and the second electrode 70 can be formed by various conductive materials known in the art by various patterning methods.

[0113] Specifically, although not shown in the figure, a passivation layer can be formed on the second electrode 70. Here, a part of the passivation layer is etched so that the second electrode 70 is exposed.

[0114] Figs. 4A to 4H are manufacturing process diagrams of a solar cell according to another embodiment of the present invention, and relate to a tandem solar cell of a perovskite solar cell and a crystalline solar cell.

[0115] First, as can be seen from Fig. 4A, a crystalline solar cell 100 is manufactured.

[0116] The crystalline solar cell 100 can be manufactured by a process of etching one surface and the other surface of the semiconductor substrate 110 such as a wafer to form an uneven structure, doping a predetermined dopant on one surface of the semiconductor substrate 110 to form a first semiconductor layer 120, and doping a predetermined dopant on the other surface of the semiconductor substrate 110 to form a second semiconductor layer 130.

[0117] The specific configurations of the semiconductor substrate 110, the first semiconductor layer 120, and the second semiconductor layer 130 are the same as those in Fig. 3A described above, so repeated explanations will be omitted.

[0118] Next, as can be seen from Fig. 4B, a buffer layer 200 is formed on the upper surface of the crystalline solar cell 100.

[0119] Since the specific configuration of the buffer layer 200 is the same as that shown in FIG. 3B described above, repeated description will be omitted.

[0120] Next, as can be seen from FIG. 4C, a hole transport layer 30 is formed on the buffer layer 200, and a light absorption layer 40 is formed on the hole transport layer 30.

[0121] Since the specific configurations of the hole transport layer 30 and the light absorption layer 40 are the same as those shown in FIG. 3C described above, repeated description will be omitted.

[0122] Next, as can be seen from FIG. 4D, an electron transport precursor layer 50a is formed on the light absorption layer 40.

[0123] Since the specific configuration of the electron transport precursor layer 50a is the same as that shown in FIG. 3D described above, repeated description will be omitted.

[0124] Next, as can be seen from FIG. 4E, oxygen plasma treatment is performed on the electron transport precursor layer 50a.

[0125] Then, oxygen is introduced into an inorganic metal nitride such as SnN or ZnN or an inorganic metal sulfide such as SnS2 or ZnS, and the electron transport precursor layer 50a changes into a first electron transport layer 51 and a second electron transport layer 52.

[0126] Since the specific configurations of the first electron transport layer 51 and the second electron transport layer 52 are the same as those shown in FIG. 2C described above, repeated description will be omitted.

[0127] Next, as can be seen from FIG. 4F, a third electron transport layer 53 is formed on the second electron transport layer 52, and an electron transport layer 50 including the first electron transport layer 51, the second electron transport layer 52, and the third electron transport layer 53 is formed.

[0128] Since the specific configuration of the third electron transport layer 53 is the same as that shown in FIG. 2D described above, repeated description will be omitted. Similar to the above-described embodiment, by omitting the step of FIG. 4E and performing the step of FIG. 4F after the step of FIG. 4D, it is also possible to form an electron transport layer 50 including the first electron transport layer 51 and the third electron transport layer 53 provided on the upper surface of the first electron transport layer 51.

[0129] Next, as can be seen from FIG. 4G, a transparent conductive layer 60 is formed on the electron transport layer 50.

[0130] Since the specific configuration of the transparent conductive layer 60 is the same as that shown in FIG. 3F described above, repeated description will be omitted.

[0131] Next, as can be seen from FIG. 4H, a first electrode 20 is formed on the lower surface of the crystalline solar cell 100, and a second electrode 70 is formed on the upper surface of the transparent conductive layer 60.

[0132] Since the specific configurations of the first electrode 20 and the second electrode 70 are the same as those shown in FIG. 3G described above, repeated description will be omitted.

[0133] Specifically, although not shown in the figure, a passivation layer can be formed on the second electrode 70. Here, a part of the passivation layer is etched so that the second electrode 70 can be exposed.

[0134] FIGS. 5A to 5D are manufacturing process diagrams of a solar cell according to another embodiment of the present invention, which is different from FIGS. 1A to 1D described above in that it further includes a step of forming a passivation layer 80 and an organic layer 90.

[0135] First, as can be seen from FIG. 5A, a first electrode 20 is formed on a substrate 10, a hole transport layer 30 is formed on the first electrode 20, a light absorption layer 40 is formed on the hole transport layer 30, a passivation layer 80 is formed on the light absorption layer 40, and an organic layer 90 is formed on the passivation layer 80.

[0136] The specific configurations of the substrate 10, the first electrode 20, the hole transport layer 30, and the light absorption layer 40 are the same as those in the above-described embodiments, and thus repeated descriptions will be omitted.

[0137] The passivation layer 80 can be made of an inorganic insulating layer, for example, an oxygen-free inorganic insulating layer such as silicon nitride.

[0138] The organic layer 90 can be made of fullerene or a fullerene derivative. As an example, the organic layer 90 can be made of C60 or PCBM ([6,6]-phenyl-C61-butyric acid methyl ester).

[0139] Next, as can be seen from FIG. 5B, an electron transport precursor layer 50a is formed on the light absorption layer 40.

[0140] The specific configuration of the electron transport precursor layer 50a is the same as that in FIG. 1B described above, and thus repeated descriptions will be omitted.

[0141] Next, as can be seen from FIG. 5C, oxygen plasma treatment is performed on the electron transport precursor layer 50a.

[0142] Then, oxygen is introduced into an inorganic metal nitride such as SnN or ZnN, and the electron transport precursor layer 50a can be changed into an electron transport layer 50 including a first electron transport layer 51, a second electron transport layer 52, and a third electron transport layer 53.

[0143] Alternatively, oxygen is introduced into an inorganic metal sulfide such as SnS, SnS2 or ZnS, and the electron transport precursor layer 50a can be changed into an electron transport layer 50 including a first electron transport layer 51, a second electron transport layer 52, and a third electron transport layer 53.

[0144] The specific configurations of the first electron transport layer 51, the second electron transport layer 52, and the third electron transport layer 53 are the same as those in FIG. 1C described above, and thus repeated descriptions will be omitted.

[0145] Here, the first electron transport layer 51 and the second electron transport layer 52 can function as a damage prevention film or a barrier film that prevents damage to the passivation layer 80 and the organic layer 90.

[0146] Next, as can be seen from FIG. 5D, a transparent conductive layer 60 is formed on the electron transport layer 50, and a second electrode 70 is formed on the transparent conductive layer 60.

[0147] Since the specific configurations of the transparent conductive layer 60 and the second electrode 70 are the same as those in FIG. 1D described above, repeated description will be omitted.

[0148] Specifically, although not shown in the figure, the formation steps of the passivation layer 80 and the organic layer 90 can also be additionally included in the embodiments according to FIGS. 2A to 2E described above. That is, in the step of FIG. 2A described above, the passivation layer 80 and the organic layer 90 are sequentially formed on the light absorption layer 40, and then, in the step of FIG. 2B, an electron transport precursor layer 50a can be formed on the organic layer 90.

[0149] In addition, the formation steps of the passivation layer 80 and the organic layer 90 can also be additionally included in the embodiments according to FIGS. 3A to 3G described above. That is, in the step of FIG. 3C described above, the passivation layer 80 and the organic layer 90 are sequentially formed on the light absorption layer 40, and then, in the step of FIG. 3D, an electron transport precursor layer 50a can be formed on the organic layer 90.

[0150] In addition, the formation steps of the passivation layer 80 and the organic layer 90 can also be additionally included in the embodiments according to FIGS. 4A to 4H described above. That is, in the step of FIG. 4C described above, the passivation layer 80 and the organic layer 90 are sequentially formed on the light absorption layer 40, and then, in the step of FIG. 4D, an electron transport precursor layer 50a can be formed on the organic layer 90.

[0151] The embodiments of the present invention have been described in more detail with reference to the accompanying drawings above. However, the present invention is not necessarily limited to such embodiments, and can be implemented in various modifications without departing from the technical idea of the present invention. Therefore, the embodiments disclosed in the present invention are not intended to limit the technical idea of the present invention but to explain it, and the scope of the technical idea of the present invention is not limited by such embodiments. Therefore, it must be understood that the embodiments described above are illustrative in all respects and not restrictive. The protection scope of the present invention must be interpreted by the scope of the claims, and all technical ideas within the equivalent scope thereof must be construed as being included in the scope of the rights of the present invention.

Claims

1. A light absorption layer containing a perovskite compound, and an electron transport layer provided on one surface of the light absorption layer, wherein the electron transport layer includes a first electron transport layer provided on one surface of the light absorption layer and a second electron transport layer provided on the first electron transport layer, the first electron transport layer contains an inorganic metal nitride, and the second electron transport layer contains an inorganic metal oxynitride, or the first electron transport layer contains an inorganic metal sulfide, and the second electron transport layer contains an inorganic metal sulfoxide, a solar cell.

2. the first electron transport layer contains SnN, and the second electron transport layer contains SnON, or the first electron transport layer contains ZnN, and the second electron transport layer contains ZnON, or The first electron transport layer comprises SnS or SnS ２ and the second electron transport layer comprises SnOS or the first electron transport layer contains ZnS, and the second electron transport layer contains ZnOS, the solar cell according to Claim 1.

3. The solar cell according to Claim 1, further comprising a passivation layer between the light absorption layer and the electron transport layer.

4. The solar cell according to Claim 3, further comprising an organic layer between the passivation layer and the electron transport layer.

5. The solar cell according to Claim 1, wherein the thickness of the second electron transport layer is greater than the thickness of the first electron transport layer.

6. the electron transport layer further includes a third electron transport layer provided on the second electron transport layer, the third electron transport layer contains an inorganic metal oxide, the solar cell according to Claim 1.

7. The solar cell according to Claim 6, wherein the third electron transport layer contains SnO or ZnO.

8. A light absorption layer containing a perovskite compound, and an electron transport layer provided on one surface of the light absorption layer, wherein the electron transport layer includes a first electron transport layer provided on one surface of the light absorption layer and a third electron transport layer provided on the first electron transport layer, the first electron transport layer contains an inorganic metal nitride or an inorganic metal sulfide, the third electron transport layer contains an inorganic metal oxide, a solar cell.

9. The first electron transport layer contains SnN, SnS or SnS ２ and the third electron transport layer comprises SnO or The solar cell according to Claim 8, wherein the first electron transport layer contains ZnN or ZnS, and the third electron transport layer contains ZnO.

10. The solar cell according to Claim 8, wherein the thickness of the third electron transport layer is greater than the thickness of the first electron transport layer.

11. The solar cell according to claim 8, further comprising a passivation layer provided between the light absorption layer and the electron transport layer, and an organic layer provided between the passivation layer and the electron transport layer.

12. Further comprising a transparent conductive layer on the electron transport layer, The solar cell according to claim 8, wherein the transparent conductive layer comprises a substance having electron transport characteristics.

13. A buffer layer provided on the other surface of the light absorption layer, and The solar cell according to claim 8, further comprising a crystalline solar cell provided on the buffer layer.

14. A buffer layer provided on the other surface of the light absorption layer, and The solar cell according to claim 1, further comprising a crystalline solar cell provided on the buffer layer.

15. A step of forming a light absorption layer containing a perovskite compound, and A step of forming an electron transport layer on one surface of the light absorption layer, The step of forming the electron transport layer includes a step of forming an electron transport precursor layer containing an inorganic metal nitride or an inorganic metal sulfide, and A method for manufacturing a solar cell, comprising a step of performing oxygen plasma treatment on the electron transport precursor layer to form a first electron transport layer containing the inorganic metal nitride or the inorganic metal sulfide, and a second electron transport layer containing an inorganic metal oxynitride or an inorganic metaloxysulfide.

16. The electron transport precursor layer and the first electron transport layer contain SnN, and the second electron transport layer contains SnON, or The electron transport precursor layer and the first electron transport layer contain ZnN, and the second electron transport layer contains ZnON, or The electron transport precursor layer and the first electron transport layer contain SnS or SnS ２ and the second electron transport layer contains SnOS or The electron transport precursor layer and the first electron transport layer contain ZnS, and the second electron transport layer contains ZnOS, according to the method for manufacturing a solar cell according to claim 15.

17. Further comprising a step of forming a third electron transport layer containing an inorganic metal oxide on the second electron transport layer, The method for manufacturing a solar cell according to claim 15, wherein the third electron transport layer comprises SnO or ZnO.

18. The method for manufacturing a solar cell according to claim 15, further comprising a step of forming a passivation layer between the light absorption layer and the electron transport layer, and a step of forming an organic layer between the passivation layer and the electron transport layer.

19. A step of forming a light absorption layer containing a perovskite compound, and A step of forming an electron transport layer on one surface of the light absorption layer, The step of forming the electron transport layer includes a step of forming an electron transport precursor layer containing an inorganic metal nitride or an inorganic metal sulfide, and a step of performing oxygen plasma treatment on the electron transport precursor layer to form a first electron transport layer containing the inorganic metal nitride or the inorganic metal sulfide and a third electron transport layer containing an inorganic metal oxide, the method for manufacturing a solar cell.

20. The first electron transport layer contains SnN, SnS, or SnS ２ and the third electron transport layer comprises SnO or The method for manufacturing a solar cell according to claim 19, wherein the first electron transport layer contains ZnN or ZnS, and the third electron transport layer contains ZnO.

21. The method for manufacturing a solar cell according to claim 19, further including a step of forming a passivation layer between the light absorption layer and the electron transport layer, and a step of forming an organic layer between the passivation layer and the electron transport layer.

22. The method for manufacturing a solar cell according to claim 19, further including a step of forming a transparent conductive layer containing a substance having electron transport characteristics on the electron transport layer.

23. Before the step of forming the light absorption layer, further including a step of forming a crystalline solar cell, and a step of forming a buffer layer on the crystalline solar cell, The method for manufacturing a solar cell according to claim 19, wherein the light absorption layer is formed on the buffer layer.

24. Before the step of forming the light absorption layer, further including a step of forming a crystalline solar cell, and a step of forming a buffer layer on the crystalline solar cell, The method for manufacturing a solar cell according to claim 15, wherein the light absorption layer is formed on the buffer layer.

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