Method for forming electron transport layer for perovskite solar cell and method for manufacturing perovskite solar cell

Abstract

The present invention relates to a method for forming an electron transport layer for a perovskite solar cell, the method comprising: a first step for preparing an atomic layer deposition process chamber in which a substrate is accommodated; a second step for introducing a stack into the atomic layer deposition process chamber and positioning the stack on an upper portion of the substrate; a third step for injecting a material for forming an electron transport layer into the atomic layer deposition process chamber; and a fourth step for performing an atomic layer deposition process to form the electron transport layer on an upper portion of the stack, wherein condition (1) is satisfied: A > B. (In condition (1), A represents a temperature inside the atomic layer deposition process chamber, and B represents a temperature of the substrate included in the atomic layer deposition process chamber.)

Description

Technical Field

[0001] The present invention relates to a method for forming an electron transport layer for a perovskite solar cell by performing an atomic layer deposition process under specific temperature conditions, and a method for manufacturing a perovskite solar cell. Background Technology

[0002] In order to address the global environmental problems caused by the consumption and use of fossil fuels, research is being actively conducted on renewable and clean alternative energy sources such as solar, wind and hydropower.

[0003] Interest in solar cells, which directly convert sunlight into electricity, is increasing significantly. Here, a solar cell refers to a battery that uses the photovoltaic effect to generate current and voltage, which produces electrons and holes by absorbing light energy from sunlight.

[0004] Currently, it is possible to manufacture NP diode-based silicon (Si) single-crystal solar cells with a light-to-energy conversion efficiency exceeding 20%, and these are actually being used for solar power generation. Furthermore, solar cells using compound semiconductors such as gallium arsenide (GaAs) with even higher conversion efficiencies also exist. However, these inorganic semiconductor-based solar cells require highly purified materials to achieve high efficiency, thus consuming significant energy in the purification of raw materials. Additionally, the processes for fabricating single crystals or thin films using these raw materials require expensive equipment, which limits the cost reduction of solar cell manufacturing and has become an obstacle to large-scale utilization.

[0005] Therefore, in order to manufacture solar cells at low cost, it is necessary to significantly reduce the cost of materials or manufacturing processes used as core components of solar cells, and research is being conducted on perovskite solar cells as an alternative to inorganic semiconductor-based solar cells that can be manufactured using low-cost materials and processes.

[0006] Recently, perovskite solar cells have been developed that use (NH3CH3)PbX3 (X = I, Br, Cl), a halogen compound with a perovskite structure, as a photoactive agent, and are being researched toward commercialization. The general structural formula of the perovskite structure is ABX3, in which the anion is located at the X position, the large cation is located at the A position, and the small cation is located at the B position.

[0007] Meanwhile, perovskite solar cells are being developed with structures of PIN perovskite single-junction solar cells or two-terminal perovskite / silicon tandem solar cells. In the case of two-terminal perovskite / silicon tandem solar cells, a transparent conductive layer is formed on top of the lower silicon solar cell, and then a hole transport layer, a perovskite light-absorbing layer, an electron transport layer, a transparent electrode, and a metal electrode are formed in sequence to manufacture the tandem solar cell.

[0008] In this context, atomic layer deposition (ALD) can be performed as one of the methods for forming the electron transport layer, and ALD is typically performed at temperatures of 100°C or higher. However, when forming the electron transport layer using such a high-temperature ALD process, there is a problem of degradation of the underlying organic layer due to the high-temperature reaction and chemical bonding of the source and reactants.

[0009] Furthermore, when electron transport layers are formed using atomic layer deposition processes at temperatures below 100°C to avoid such problems, the issue arises that photoelectric conversion efficiency decreases due to changes in the density and band gap of the formed electron transport layer (which degrades the properties of the electron transport layer and its charge transfer characteristics). Summary of the Invention

[0010] Technical issues

[0011] The present invention aims to overcome the above-mentioned problems and provides a method for forming an electron transport layer for perovskite solar cells, the method not only minimizing thermal damage and preventing interface degradation by forming the electron transport layer through an atomic layer deposition process under specific temperature conditions, but also minimizing the reduction in performance of perovskite solar cells and ensuring stability; and a method for manufacturing perovskite solar cells.

[0012] Technical solution

[0013] To address the aforementioned problems, the method for forming an electron transport layer for a perovskite solar cell according to the present invention may include: step 1, preparing an atomic layer deposition chamber therein for accommodating a substrate; step 2, placing a stack in the atomic layer deposition chamber to position the stack on top of the substrate; step 3, injecting an electron transport layer forming material into the atomic layer deposition chamber; and step 4, performing an atomic layer deposition process to form an electron transport layer on top of the stack.

[0014] In a preferred embodiment of the present invention, the method for forming an electron transport layer for a perovskite solar cell according to the present invention can satisfy the following condition (1):

[0015] (1) A > B

[0016] In condition (1), A represents the temperature inside the chamber for atomic layer deposition process, and B represents the temperature of the substrate included inside the chamber for atomic layer deposition process.

[0017] In a preferred embodiment of the present invention, the atomic layer deposition process in step 4 can be performed under the following conditions: the temperature inside the atomic layer deposition process chamber is 85°C to 150°C, and the temperature of the substrate included inside the atomic layer deposition process chamber is 80°C or lower.

[0018] In a preferred embodiment of the present invention, the atomic layer deposition process in step 4 can be performed under the following conditions: the temperature inside the atomic layer deposition process chamber is 85°C to 120°C, and the temperature of the substrate included inside the atomic layer deposition process chamber is 40°C to 70°C.

[0019] In a preferred embodiment of the present invention, the stacked body may be a structure in which a hole transport layer and a perovskite light absorption layer are stacked sequentially, and an electron transport layer may be formed on top of the perovskite light absorption layer.

[0020] In a preferred embodiment of the present invention, the stack may have a structure in which a hole transport layer, a perovskite light absorption layer and an intermediate layer are stacked sequentially, and an electron transport layer may be formed on top of the perovskite light absorption layer.

[0021] In a preferred embodiment of the present invention, the intermediate layer may comprise fullerene-based organic materials.

[0022] In a preferred embodiment of the present invention, the fullerene series organic materials may include those selected from C 60 C 70 One or more of PC60BM and PC70BM.

[0023] In a preferred embodiment of the present invention, the average thickness of the electron transport layer can be from 3 nm to 20 nm.

[0024] In a preferred embodiment of the present invention, the electron transport layer forming material may include materials selected from tin oxide (SnO). x Nickel oxide (NiO) x ), Tin oxide (SnO2), Titanium dioxide (TiO2), Zinc oxide (ZnO), Barium tin oxide (BaSnO3), Niobium hydroxide (NbOH), Hafnium oxide (HfO) x ), zirconium oxide (ZrO x ), vanadium oxide (VO) x One or more of niobium pentoxide (Nb2O5) and niobium pentoxide (Nb2O5).

[0025] Meanwhile, the method for manufacturing perovskite solar cells according to the present invention may include: step 1, manufacturing a stack by forming a perovskite light-absorbing layer on top of a hole transport layer; step 2, forming an electron transport layer on top of the perovskite light-absorbing layer by an atomic layer deposition process; and step 3, sequentially forming a transparent electrode and a metal electrode on top of the electron transport layer.

[0026] In a preferred embodiment of the invention, step 2 of the atomic layer deposition process in the method for manufacturing a perovskite solar cell according to the invention can be performed by including: step 2-1, preparing an atomic layer deposition process chamber in which a substrate is housed; step 2-2, placing a stack in the atomic layer deposition process chamber to position the stack on top of the substrate; step 2-3, injecting an electron transport layer forming material into the atomic layer deposition process chamber; and step 2-4, performing an atomic layer deposition process to form an electron transport layer on top of the perovskite light-absorbing layer.

[0027] Furthermore, the method for manufacturing perovskite solar cells according to the present invention may include: step 1, manufacturing a stack by sequentially forming a perovskite light-absorbing layer and an intermediate layer on top of a hole transport layer; step 2, forming an electron transport layer on top of the intermediate layer by an atomic layer deposition process; and step 3, sequentially forming a transparent electrode and a metal electrode on top of the electron transport layer.

[0028] In a preferred embodiment of the invention, step 2 of the atomic layer deposition process in the method for manufacturing perovskite solar cells according to the invention can be performed by including: step 2-1, preparing an atomic layer deposition process chamber in which a substrate is housed; step 2-2, placing a stack in the atomic layer deposition process chamber to position the stack on top of the substrate; step 2-3, injecting an electron transport layer forming material into the atomic layer deposition process chamber; and step 2-4, performing an atomic layer deposition process to form an electron transport layer on top of an intermediate layer.

[0029] In a preferred embodiment of the present invention, the method for manufacturing perovskite solar cells according to the present invention can satisfy the following condition (1):

[0030] (1) A > B

[0031] In condition (1), A represents the temperature inside the chamber for atomic layer deposition process, and B represents the temperature of the substrate included inside the chamber for atomic layer deposition process.

[0032] In a preferred embodiment of the invention, the atomic layer deposition process of steps 2-4 of the method for manufacturing perovskite solar cells according to the invention can be performed under the following conditions: the temperature inside the atomic layer deposition process chamber is 85°C to 150°C, and the temperature of the substrate included inside the atomic layer deposition process chamber is 80°C or lower.

[0033] Meanwhile, the method for manufacturing a tandem perovskite solar cell according to the present invention may include: step 1, manufacturing a tandem body by sequentially forming a transparent conductive layer, a hole transport layer and a perovskite light-absorbing layer on the top of the solar cell; step 2, forming an electron transport layer on the top of the perovskite light-absorbing layer by an atomic layer deposition process; and step 3, sequentially forming a transparent electrode and a metal electrode on the top of the electron transport layer.

[0034] In a preferred embodiment of the invention, step 2 of the atomic layer deposition process in the method for manufacturing a tandem perovskite solar cell according to the invention can be performed by including: step 2-1, preparing an atomic layer deposition process chamber in which a substrate is housed; step 2-2, placing a stack in the atomic layer deposition process chamber to position the stack on top of the substrate; step 2-3, injecting an electron transport layer forming material into the atomic layer deposition process chamber; and step 2-4, performing an atomic layer deposition process to form an electron transport layer on top of the perovskite light-absorbing layer.

[0035] Furthermore, the method for manufacturing a tandem perovskite solar cell according to the present invention may include: step 1, manufacturing a tandem body by sequentially forming a transparent conductive layer, a hole transport layer, a perovskite light-absorbing layer and an intermediate layer on top of the solar cell; step 2, forming an electron transport layer on top of the intermediate layer by an atomic layer deposition process; and step 3, sequentially forming a transparent electrode and a metal electrode on top of the electron transport layer.

[0036] In a preferred embodiment of the invention, step 2 of the atomic layer deposition process in the method for manufacturing a tandem perovskite solar cell according to the invention can be performed by including: step 2-1, preparing an atomic layer deposition process chamber in which a substrate is housed; step 2-2, placing the tandem body in the atomic layer deposition process chamber to position the tandem body on top of the substrate; step 2-3, injecting an electron transport layer forming material into the atomic layer deposition process chamber; and step 2-4, performing an atomic layer deposition process to form an electron transport layer on top of an intermediate layer.

[0037] In a preferred embodiment of the present invention, the method for manufacturing tandem perovskite solar cells according to the present invention can satisfy the following condition (1):

[0038] (1) A > B

[0039] In condition (1), A represents the temperature inside the chamber for atomic layer deposition process, and B represents the temperature of the substrate included inside the chamber for atomic layer deposition process.

[0040] In a preferred embodiment of the invention, the atomic layer deposition process of steps 2-4 of the method for manufacturing tandem perovskite solar cells according to the invention can be performed under the following conditions: wherein the temperature inside the atomic layer deposition process chamber is 85°C to 150°C, and the temperature of the substrate included inside the atomic layer deposition process chamber is 80°C or lower.

[0041] In a preferred embodiment of the present invention, the solar cell may be a polycrystalline silicon solar cell, a crystalline silicon solar cell, a perovskite solar cell, a gallium arsenide (GaAs) solar cell, a cadmium telluride (CdTe) solar cell, a CIGS (CuInGaSe) solar cell, a CZTS (Cu2ZnSnS4) solar cell, an organic solar cell, a fuel-sensitized solar cell, or a group 3 to 5 compound solar cell.

[0042] Beneficial effects

[0043] The method for forming an electron transport layer for a perovskite solar cell and the method for manufacturing a perovskite solar cell according to the present invention can induce interface stabilization and improve voltage characteristics and fill factor characteristics by enhancing charge transfer characteristics through better-matched energy levels and hole blocking characteristics, thereby leading to an improvement in power conversion efficiency. Attached Figure Description

[0044] Figure 1 This is a schematic diagram illustrating a chamber for an atomic layer deposition process according to a preferred embodiment of the present invention.

[0045] Figure 2 This is an FE-SEM image of the electron transport layer surface of the tandem silicon / perovskite heterojunction solar cell manufactured in Example 1.

[0046] Figure 3 This is an FE-SEM image of the electron transport layer surface of the tandem silicon / perovskite heterojunction solar cell fabricated in Comparative Example 1. Detailed Implementation

[0047] The invention will be described in more detail below.

[0048] Perovskite solar cells are being developed using either PIN perovskite single-junction solar cells or two-terminal perovskite / silicon tandem solar cells. In the case of two-terminal perovskite / silicon tandem solar cells, a transparent conductive layer is formed on top of the lower silicon solar cell, followed by the sequential formation of a hole transport layer, a perovskite light-absorbing layer, an electron transport layer, a transparent electrode, and a metal electrode to fabricate the tandem solar cell.

[0049] In this context, atomic layer deposition (ALD) can be performed as one of the methods for forming the electron transport layer, and ALD is typically performed at temperatures of 100°C or higher. However, when forming the electron transport layer using such a high-temperature ALD process, there is a problem of degradation of the underlying organic layer due to the high-temperature reaction and chemical bonding of the source and reactants.

[0050] Furthermore, when electron transport layers are formed using atomic layer deposition processes at temperatures below 100°C to avoid such problems, the issue arises that photoelectric conversion efficiency decreases due to changes in the density and band gap of the formed electron transport layer (which degrades the properties of the electron transport layer and its charge transfer characteristics).

[0051] Therefore, the present invention relates to a method for forming an electron transport layer for a perovskite solar cell, the method forming the electron transport layer by an atomic layer deposition process under specific temperature conditions, thereby minimizing thermal damage and preventing degradation at the interface, and minimizing the reduction in performance of the perovskite solar cell while ensuring stability; and to a method for manufacturing a perovskite solar cell.

[0052] The method for forming an electron transport layer for a perovskite solar cell according to the present invention includes steps 1 to 4.

[0053] The electron transport layer (ETL) is a layer that transports electrons formed in the perovskite light-absorbing layer while blocking the movement of holes.

[0054] First, when referring to Figure 1 In the description, step 1 of the method for forming an electron transport layer for a perovskite solar cell according to the present invention can be a chamber 10 for preparing an atomic layer deposition (ALD) process in which a substrate 2 is housed.

[0055] Next, step 2 of the method for forming an electron transport layer for a perovskite solar cell according to the present invention may involve placing a stack 20 inside the chamber 10 for the atomic layer deposition process prepared in step 1 to position the stack 20 on top of the substrate 2.

[0056] Next, step 3 of the method for forming an electron transport layer for a perovskite solar cell according to the present invention may be to inject an electron transport layer forming material into the chamber 10 of an atomic layer deposition process.

[0057] In this case, the electron transport layer forming material is a material used to form the electron transport layer via an atomic layer deposition process, and may include materials selected from tin oxide (SnO). x Nickel oxide (NiO) x ), Tin oxide (SnO2), Titanium dioxide (TiO2), Zinc oxide (ZnO), Barium tin oxide (BaSnO3), Niobium hydroxide (NbOH), Hafnium oxide (HfO) x ), zirconium oxide (ZrO x ), vanadium oxide (VO) x It may contain one or more of niobium pentoxide (Nb2O5) and preferably may include tin oxide (SnO2).

[0058] Finally, step 4 of the method for forming an electron transport layer for a perovskite solar cell according to the present invention may be to form an electron transport layer on top of a stack 20 introduced into an atomic layer deposition chamber 10 by performing an atomic layer deposition process.

[0059] Meanwhile, the stack 20 may have a structure in which a hole transport layer and a perovskite light absorption layer are stacked in sequence, and the electron transport layer may be formed on top of the perovskite light absorption layer by step 4 of the method for forming an electron transport layer for a perovskite solar cell.

[0060] Furthermore, the stack 20 may have a structure in which a hole transport layer, a perovskite light absorption layer and an intermediate layer are stacked sequentially, and the electron transport layer may be formed on top of the intermediate layer by step 4 of the method for forming an electron transport layer for a perovskite solar cell.

[0061] Meanwhile, the method for forming an electron transport layer for perovskite solar cells according to the present invention can satisfy the following condition (1).

[0062] (1) A > B

[0063] In the above condition (1), A represents the temperature inside chamber 10 of atomic layer deposition process, and B represents the temperature of substrate 2 included inside chamber 10 of atomic layer deposition process.

[0064] In this way, by satisfying the conditions (1) of the present invention and forming an electron transport layer, not only is thermal damage minimized and degradation at the interface prevented, but the performance degradation of the perovskite solar cell is also minimized and stability is ensured.

[0065] Specifically, the atomic layer deposition process in step 4 of the method for forming an electron transport layer for a perovskite solar cell according to the present invention can be performed under the following conditions: the temperature inside chamber 10 of the atomic layer deposition process is 85°C to 150°C, and preferably 85°C to 120°C, and the temperature of the substrate 2 included inside chamber 10 of the atomic layer deposition process is 80°C or lower, preferably 40°C to 70°C, and more preferably 57°C to 63°C. By forming the electron transport layer while satisfying these temperature conditions, not only can thermal damage be minimized and interface degradation prevented, but the performance degradation of the perovskite solar cell can also be minimized and stability can be ensured.

[0066] Furthermore, the average thickness of the electron transport layer formed by the method for forming an electron transport layer for perovskite solar cells according to the present invention can be from 3 nm to 20 nm, preferably from 4 nm to 15 nm, and more preferably from 4 nm to 8 nm. If the average thickness is less than 3 nm, it may be difficult to form a layer with a uniform thickness, which may lead to a problem of potentially deteriorated electron transport characteristics. If it is greater than 20 nm, not only may the electron transport characteristics decrease, but there may also be a problem of increased series resistance.

[0067] The hole transport layer (HTL) included in the stack 20 is a layer that transports holes formed in the perovskite light-absorbing layer while blocking electron movement, and may contain inorganic and / or organic hole transport materials.

[0068] In this case, the inorganic hole transport material may include materials selected from nickel oxide (NiO). x ), CuSCN, CuCrO2, CuI, CuO x One or more of CuS, CuI, CuPc, CIS, CuGaO2, PbS, MoOx, AlOx (aluminum oxide), CuAlOx, aluminum oxide nanoparticles, silica nanoparticles, nickel oxide nanoparticles, hafnium nanoparticles, and V2O5.

[0069] In addition, organic hole transport materials may include one or more of the following: carbazole derivatives, polyarylalkane derivatives, phenylenediamine derivatives, arylamine derivatives, amino-substituted chalcone derivatives, styrene-anthracene derivatives, fluorene derivatives, hydrazone derivatives, stilbene derivatives, silazane derivatives, aromatic tertiary amine compounds, styrene-amine compounds, compounds based on aromatic dimethyl groups, compounds based on porphyrins, compounds based on phthalocyanines, polythiophene derivatives, polypyrrole derivatives, poly(p-phenylene oxide) derivatives, pentacene, coumarin 6 (3-(2-benzothiazolyl)-7-(diethylamino)coumarin), ZnPC (zinc phthalocyanine), CuPC (copper phthalocyanine), TiOPC (titanium oxide phthalocyanine), spiro-MeOT AD (2,2',7,7'-tetratetra(N,N-p-dimethoxyphenylamino)-9,9'-spirodifluorene), F16CuPC (copper(II)1,2,3,4,8,9,10,11,15,16,17,18,22,23,24,25-hexadecylfluoro-29H,31H-phthalocyanine), SubPc (dichloroboron phthalocyanine) and N3 (cis-di(thiocyanoxy)-bis(2,2'-bipyridyl-4,4'-dicarboxylic acid)-ruthenium(II), P3HT (poly[3-hexylthiophene]), MDMO-PPV (poly[2-methoxy-5-(3',7'-dimethyloctyloxy)]-1,4-phenyleneethylene), MEH-PPV (poly[2-methoxy-5-(3',7'-dimethyloctyloxy)]-1,4-phenyleneethylene), [[2,22',7,77'-tetra(N,N-di-p-methoxyaniline)-9,9,9'-spirodifluoro]], P3OT (poly(3-octylthiophene)), POT (poly(octylthiophene)), P3DT (poly(3-decylthiophene)), P3DDT (poly(3-dodecylthiophene)), PPV (poly(p-phenyleneethylene)), TFB (poly(9,9'-dioctylfluorene-copolymer-N-(4-butylphenyl)diphenylamine), polyaniline, spiro-MeOTAD ([2,22',7,77'-tetra(N,N-di-p-methoxyaniline)-9,9,9'-spirodifluoro]), PCPDTBT (poly[2,1,3-benzothiadiazole-4,7-diyl[4,4-bis(2-ethylhexyl-4H-cyclopenta[2,1-b:3,4-b'])) Dithiophene-2,6-diyl]]), Si-PCPDTBT (poly[(4,4'-bis(2-ethylhexyl)dithiophene[3,2-b:2',3'-d]silazopendiene)-2,6-diyl-alternating-(2,1,3-benzothiadiazole)-4,7-diyl]), PBDTTPD (poly((4,8-diethylhexyloxy)), PFDTBT (poly[2,7-(9-(2-ethylhexyl)-9-hexyl-fluorene)-alternating-5,5-(4',7,-di-2-thiophene-2',1',3'-benzothiadiazole)]), PFO-DBT (poly[2,7-9,9-(dioctyl-fluorene)-alternating-5,5-(4',7'-di-2-thiophene-2',1',3'-benzothiadiazole)]), PSiFDTBT (poly[(2,7-dioctylsilylfluorene)-2,7-diyl-alternating-(4,7-bis(2-thienyl)-2,1,3-benzothiadiazole)-5,5'-diyl]), PCDTBT (poly[[9-(1-octylnonyl)-9H-carbazole-2,7-diyl]-2,5-thiophenediyl-2,1,3-benzothiadiazole-4,7-diyl-2,5-thiophenediyl]), PFB (poly(9,9'-dioctylfluorene-copolymer-bis(N,N) '-(4-Butylphenyl))bis(N,N'-phenyl-1,4-phenylene)diamine), F8BT (poly(9,9'-dioctylfluorene-copolymer-benzothiadiazole), PEDOT (poly(3,4-ethylenedioxythiophene)), PEDOT:PSS poly(3,4-ethylenedioxythiophene) poly(styrene sulfonate), PTAA (poly(triarylamine)), 2-PACz, MeO-2PACz, Br-2PACz, Me-4PACz, MeO-4PACz and 6-PACz.

[0070] In addition, methods for forming hole transport layers include coating and vacuum deposition, and methods for applying hole transport layers include gravure coating, bar coating, printing, spraying, spin coating, dip coating and mold coating.

[0071] Furthermore, there is no particular limitation on the thickness of the hole transport layer, but it is preferable to have a thickness of 5 nm to 40 nm, and more preferably 10 nm to 30 nm.

[0072] The perovskite light-absorbing layer included in the stack 20 may contain a general perovskite material used in light-absorbing layers of solar cells, and as a preferred example, it may include a perovskite material represented by the following chemical formula 1.

[0073] [Chemical Formula 1]

[0074] CMX3

[0075] In the above chemical formula 1, C is a monovalent cation, which may include amines, ammonium, Group 1 metals, Group 2 metals and / or other cations or cation-like compounds, and preferably, it may be formamidinium (FA), methylammonium (MA), FAMA, CsFAMA, CsFA, or N(R)4. + (Here, R can be the same or different groups, and R is a straight-chain alkyl group having 1 to 5 carbon atoms, a branched alkyl group having 3 to 5 carbon atoms, a phenyl group, an alkylphenyl group, an alkoxyphenyl group, or a haloalkyl group.)

[0076] Furthermore, M in Formula 1 is a divalent cation and may include one or both of Fe, Co, Ni, Cu, Sn, Pb, Bi, Ge, Ti, Eu, and Zr.

[0077] Furthermore, X in Formula 1 is a monovalent anion and may include one or more halogen elements selected from F, Cl, Br, and I and / or Group 16 anions. As a preferred example, X may be I. x Br3₋ x (0≤x≤3).

[0078] Furthermore, a preferred embodiment of chemical formula 1 may be FAPbI x Br3₋ x (0≤x≤3), MAPbI x Br3₋ x (0≤x≤3), CSFAPbI x Br3₋ x (0≤x≤3), CSMAFAPbI x Br3₋ x (0≤x≤3), CH3NH3PbX3 (X= Cl, Br, I, BrI2 or Br2I), CH3NH3SnX3 (X= Cl, Br or I), CH(=NH)NH3PbX3 (X= Cl, Br, I, BrI2 or Br2I) or CH(=NH)NH3SnX3 (X= Cl, Br or I).

[0079] Meanwhile, the perovskite light-absorbing layer can be a single layer composed of the same perovskite material, or it can be a multilayer structure in which multiple layers composed of different perovskite materials are stacked. Furthermore, the light-absorbing layer composed of one type of perovskite material can contain heterogeneous perovskite material that is different from the type of perovskite material that has a columnar shape (e.g., columnar, plate-shaped, needle-shaped, linear, or rod-shaped).

[0080] In addition, methods for forming perovskite light-absorbing layers include coating and vacuum deposition, and methods for applying the layer include gravure coating, bar coating, printing, spraying, spin coating, dip coating, inkjet coating, and die coating.

[0081] Furthermore, there is no particular limitation on the thickness of the perovskite light-absorbing layer, but it is preferable to have a thickness of 50 nm to 800 nm, and more preferably 300 nm to 600 nm.

[0082] The intermediate layer included in the laminate 20 may contain fullerene-based organic materials. In this case, the fullerene-based organic materials may include those selected from C 60 C 70One or more of PC60BM and PC70BM, and preferably, it may include C 60 Furthermore, the intermediate layer included in the stack 20 may also contain lithium fluoride (LiF).

[0083] Furthermore, the average thickness of the intermediate layer can be from 3 nm to 30 nm, preferably from 5 nm to 20 nm, and more preferably from 11 nm to 17 nm. If the average thickness is less than 3 nm, the intermediate layer may not be able to form uniformly on the rough surface of the perovskite light-absorbing layer, which may lead to a decrease in charge transfer capability. Furthermore, if the average thickness is greater than 30 nm, the intermediate layer may absorb light that should be absorbed by the perovskite light-absorbing layer, thereby hindering the light-receiving characteristics of the perovskite light-absorbing layer, which may lead to a decrease in the performance of the solar cell.

[0084] Meanwhile, the method for manufacturing perovskite solar cells according to the present invention includes steps 1 to 3.

[0085] First, in step 1 of the method for manufacturing a perovskite solar cell according to the present invention, a stack can be manufactured by forming a perovskite light-absorbing layer on top of the hole transport layer. In this case, the hole transport layer and the perovskite light-absorbing layer are the same as described above.

[0086] Next, in step 2 of the method for manufacturing a perovskite solar cell according to the present invention, an electron transport layer can be formed on the perovskite light-absorbing layer formed in step 1 by an atomic layer deposition process. As described above, the electron transport layer (ETL) is a layer that transports electrons formed in the perovskite light-absorbing layer while simultaneously blocking the movement of holes.

[0087] Specifically, step 2 of the atomic layer deposition process in the method for manufacturing perovskite solar cells according to the present invention includes steps 2-1 to 2-4.

[0088] Reference Figure 1 In step 2-1 of the method for manufacturing perovskite solar cells according to the present invention, a chamber 10 for atomic layer deposition (ALD) process in which a substrate 2 is housed can be prepared.

[0089] Next, in step 2-2 of the method for manufacturing perovskite solar cells according to the present invention, a stack 20 can be placed inside the atomic layer deposition process chamber 10 prepared in step 1, and the stack 20 can be positioned on top of the substrate 2.

[0090] Next, in steps 2-3 of the method for manufacturing perovskite solar cells according to the present invention, material for forming an electron transport layer may be injected into the atomic layer deposition chamber 10.

[0091] In this case, the electron transport layer forming material is a material used to form the electron transport layer via an atomic layer deposition process, and may include materials selected from tin oxide (SnO). x Nickel oxide (NiO) x ), Tin oxide (SnO2), Titanium dioxide (TiO2), Zinc oxide (ZnO), Barium tin oxide (BaSnO3), Niobium hydroxide (NbOH), Hafnium oxide (HfO) x ), zirconium oxide (ZrO x ), vanadium oxide (VO) x It may contain one or more of niobium pentoxide (Nb2O5) and preferably may include tin oxide (SnO2).

[0092] Finally, in steps 2-4 of the method for manufacturing perovskite solar cells according to the present invention, an atomic layer deposition process can be performed to form an electron transport layer on top of the stack 20 placed inside the atomic layer deposition process chamber 10.

[0093] Meanwhile, the stack 20 may have a structure in which a hole transport layer and a perovskite light absorption layer are stacked sequentially, and an electron transport layer may be formed on top of the perovskite light absorption layer by step 2-4 of the method for manufacturing a perovskite solar cell according to the present invention.

[0094] Furthermore, the method for manufacturing perovskite solar cells according to the present invention can satisfy the following condition (1).

[0095] (1) A > B

[0096] In the above condition (1), A represents the temperature inside chamber 10 of atomic layer deposition process, and B represents the temperature of substrate 2 included inside chamber 10 of atomic layer deposition process.

[0097] In this way, by satisfying the conditions (1) of the present invention and forming an electron transport layer, not only is thermal damage minimized and degradation at the interface prevented, but the performance degradation of the perovskite solar cell is also minimized and stability is ensured.

[0098] Specifically, the atomic layer deposition process in steps 2-4 of the method for manufacturing perovskite solar cells according to the present invention can be performed under the following conditions: the temperature inside chamber 10 of the atomic layer deposition process is 85°C to 150°C, and preferably 85°C to 120°C, and the temperature of the substrate 2 included inside chamber 10 of the atomic layer deposition process is 80°C or lower, preferably 40°C to 70°C, and more preferably 57°C to 63°C. By forming an electron transport layer while meeting these temperature conditions, not only can thermal damage be minimized and interface degradation prevented, but the performance degradation of the perovskite solar cell can also be minimized and stability can be ensured.

[0099] Furthermore, the average thickness of the electron transport layer formed in step 2 of the method for manufacturing perovskite solar cells according to the present invention can be from 3 nm to 20 nm, preferably from 4 nm to 15 nm, and more preferably from 4 nm to 8 nm. If the average thickness is less than 3 nm, it may be difficult to form a layer with a uniform thickness, which may lead to a problem of potentially deteriorating electron transport characteristics. If it is greater than 20 nm, not only may the electron transport characteristics be reduced, but there may also be a problem of potentially increasing series resistance.

[0100] Next, in step 3 of the method for manufacturing perovskite solar cells according to the present invention, a transparent electrode and a metal electrode may be sequentially formed on top of the electron transport layer formed in step 2.

[0101] A transparent electrode can be formed on top of the electron transport layer by a deposition process. In this case, the deposition can be performed using general deposition processes used in the art, and preferably, the deposition process can be performed by sputtering.

[0102] In addition, the transparent electrode can be a transparent thin film deposited with ITO (indium tin oxide), FTO (fluorine-doped tin oxide), ATO (Sb2O3-doped tin oxide), GTO (gallium-doped tin oxide), ZTO (tin-doped zinc oxide), ZTO:Ga (gallium-doped ZTO), IGZO (indium gallium zinc oxide), IZO (indium-doped zinc oxide), or AZO (aluminum-doped zinc oxide).

[0103] Furthermore, the thickness of the transparent electrode is not individually limited, but it can preferably have a thickness of 50 nm to 200 nm, and more preferably 60 nm to 140 nm.

[0104] Metal electrodes can be formed by patterning a metal material on top of a transparent electrode. Specifically, the patterning process mainly consists of deposition, exposure (photolithography), and etching. The metal electrode can be formed on top of the transparent electrode by spreading a metal material in thin film onto a substrate surface, printing a pattern through exposure, and then removing unwanted portions. Alternatively, the patterning process can also be performed using a metal paste containing the metal material via screen printing.

[0105] In this case, the metallic material may include one or more of the following: Pt, Au, Ni, Cu, Ag, In, Ru, Pd, Rh, Ir, Os, C, and conductive polymers.

[0106] Furthermore, there is no separate limitation on the thickness of the metal electrode, but it can preferably have a thickness of 50 nm to 2.5 μm.

[0107] Meanwhile, as another method, the method for manufacturing perovskite solar cells according to the present invention includes steps 1 to 3.

[0108] First, in step 1 of the method for manufacturing a perovskite solar cell according to the present invention, a stack can be manufactured by sequentially forming a perovskite light-absorbing layer and an intermediate layer on top of a hole transport layer. In this case, the hole transport layer, the perovskite light-absorbing layer, and the intermediate layer are the same as described above.

[0109] Next, in step 2 of the method for manufacturing a perovskite solar cell according to the present invention, an electron transport layer can be formed on top of the intermediate layer formed in step 1 by an atomic layer deposition process. As described above, the electron transport layer (ETL) is a layer that transports electrons formed in the perovskite light-absorbing layer while simultaneously blocking the movement of holes.

[0110] Specifically, step 2 of the atomic layer deposition process in the method for manufacturing perovskite solar cells according to the present invention includes steps 2-1 to 2-4.

[0111] Reference Figure 1 In step 2-1 of the method for manufacturing perovskite solar cells according to the present invention, a chamber 10 for atomic layer deposition (ALD) process in which a substrate 2 is housed can be prepared.

[0112] Next, in step 2 of the method for manufacturing perovskite solar cells according to the present invention, a stack 20 can be placed inside the atomic layer deposition process chamber 10 prepared in step 1, and the stack 20 can be positioned on top of the substrate 2.

[0113] Next, in steps 2-3 of the method for manufacturing perovskite solar cells according to the present invention, material for forming an electron transport layer may be injected into the atomic layer deposition chamber 10.

[0114] In this case, the electron transport layer forming material is a material used to form the electron transport layer via an atomic layer deposition process, and may include materials selected from tin oxide (SnO). x Nickel oxide (NiO) x ), Tin oxide (SnO2), Titanium dioxide (TiO2), Zinc oxide (ZnO), Barium tin oxide (BaSnO3), Niobium hydroxide (NbOH), Hafnium oxide (HfO) x ), zirconium oxide (ZrO x ), vanadium oxide (VO) x It may contain one or more of niobium pentoxide (Nb2O5) and preferably may include tin oxide (SnO2).

[0115] Finally, in steps 2-4 of the method for manufacturing perovskite solar cells according to the present invention, an atomic layer deposition process can be performed to form an electron transport layer on top of the stack 20 placed inside the atomic layer deposition process chamber 10.

[0116] Meanwhile, the stack 20 may have a structure in which a hole transport layer, a perovskite light absorption layer and an intermediate layer are stacked in sequence, and an electron transport layer may be formed on top of the intermediate layer by step 2-4 of the method for manufacturing perovskite solar cells according to the present invention.

[0117] Furthermore, the method for manufacturing perovskite solar cells according to the present invention can satisfy the following condition (1).

[0118] (1) A > B

[0119] In the above condition (1), A represents the temperature inside chamber 10 of atomic layer deposition process, and B represents the temperature of substrate 2 included inside chamber 10 of atomic layer deposition process.

[0120] In this way, by satisfying the conditions (1) of the present invention and forming an electron transport layer, not only is thermal damage minimized and degradation at the interface prevented, but the performance degradation of the perovskite solar cell is also minimized and stability is ensured.

[0121] Specifically, the atomic layer deposition process in steps 2-4 of the method for manufacturing perovskite solar cells according to the present invention can be performed under the following conditions: the temperature inside chamber 10 of the atomic layer deposition process is 85°C to 150°C, and preferably 85°C to 120°C, and the temperature of the substrate 2 included inside chamber 10 of the atomic layer deposition process is 80°C or lower, preferably 40°C to 70°C, and more preferably 57°C to 63°C. By forming an electron transport layer while meeting these temperature conditions, not only can thermal damage be minimized and interface degradation prevented, but the performance degradation of the perovskite solar cell can also be minimized and stability can be ensured.

[0122] Furthermore, the average thickness of the electron transport layer formed in step 2 of the method for manufacturing perovskite solar cells according to the present invention can be from 3 nm to 20 nm, preferably from 4 nm to 15 nm, and more preferably from 4 nm to 8 nm. If the average thickness is less than 3 nm, it may be difficult to form a layer with a uniform thickness, which may lead to a problem of potentially deteriorating electron transport characteristics. If it is greater than 20 nm, not only may the electron transport characteristics be reduced, but there may also be a problem of potentially increasing series resistance.

[0123] Next, in step 3 of the method for manufacturing a perovskite solar cell according to the present invention, a transparent electrode and a metal electrode may be sequentially formed on the electron transport layer formed in step 2. In this case, the transparent electrode and the metal electrode are the same as described above.

[0124] Furthermore, the method for manufacturing tandem perovskite solar cells according to the present invention includes steps 1 to 3.

[0125] First, in step 1 of the method for manufacturing a tandem perovskite solar cell according to the present invention, the tandem structure can be manufactured by sequentially forming a transparent conductive layer, a hole transport layer, and a perovskite light-absorbing layer on top of the solar cell. In this case, the hole transport layer and the perovskite light-absorbing layer are the same as described above.

[0126] Solar cells can be polycrystalline silicon solar cells, crystalline silicon solar cells, perovskite solar cells, gallium arsenide (GaAs) solar cells, cadmium telluride (CdTe) solar cells, CIGS (CuInGaSe) solar cells, CZTS (Cu2ZnSnS4) solar cells, organic solar cells, fuel-sensitized solar cells, or group 3 to 5 compound solar cells.

[0127] Furthermore, the thickness of the solar cell is not individually limited, but it is preferably 140 μm to 250 μm, and more preferably 160 μm to 200 μm.

[0128] The transparent conductive layer is a layer that induces the recombination of electrons and holes in solar cells and perovskite light-absorbing layers, and can be a transparent thin film deposited thereon with ITO (indium tin oxide), FTO (fluorine-doped tin oxide), ATO (Sb2O3-doped tin oxide), GTO (gallium-doped tin oxide), ZTO (tin-doped zinc oxide), ZTO:Ga (gallium-doped ZTO), IGZO (indium gallium zinc oxide), IZO (indium-doped zinc oxide), or AZO (aluminum-doped zinc oxide).

[0129] Furthermore, as an example of forming a transparent conductive layer, when using silicon solar cells doped with n-type or p-type impurities as solar cells, the silicon solar cells doped with n-type or p-type impurities are treated with hydrofluoric acid to remove SiO. x An oxide film is removed, and then residual hydrofluoric acid is removed using ultrapure water. A transparent conductive layer can then be formed on top of the silicon solar cell from which the oxide film has been removed by sputtering.

[0130] Furthermore, there is no particular limitation on the thickness of the transparent conductive layer, but it is preferable to have a thickness of 5 nm to 50 nm, and more preferably 15 nm to 25 nm.

[0131] Next, in step 2 of the method for manufacturing a tandem perovskite solar cell according to the present invention, an electron transport layer can be formed on the perovskite light-absorbing layer formed in step 1 by an atomic layer deposition process. As described above, the electron transport layer (ETL) is a layer that transports electrons formed in the perovskite light-absorbing layer while blocking the movement of holes.

[0132] Specifically, step 2 of the atomic layer deposition process in the method for manufacturing tandem perovskite solar cells according to the present invention includes steps 2-1 to 2-4.

[0133] Reference Figure 1 In step 2-1 of the method for manufacturing tandem perovskite solar cells according to the present invention, a chamber 10 for atomic layer deposition (ALD) process in which a substrate 2 is housed can be prepared.

[0134] Next, in step 2-2 of the method for manufacturing a tandem perovskite solar cell according to the present invention, the stack 20 can be placed inside the atomic layer deposition process chamber 10 prepared in step 1, and the stack 20 can be positioned on top of the substrate 2.

[0135] Next, in steps 2-3 of the method for manufacturing tandem perovskite solar cells according to the present invention, material for forming an electron transport layer may be injected into the atomic layer deposition chamber 10.

[0136] In this case, the electron transport layer forming material is a material used to form the electron transport layer via an atomic layer deposition process, and may include materials selected from tin oxide (SnO). x Nickel oxide (NiO) x ), Tin oxide (SnO2), Titanium dioxide (TiO2), Zinc oxide (ZnO), Barium tin oxide (BaSnO3), Niobium hydroxide (NbOH), Hafnium oxide (HfO) x ), zirconium oxide (ZrO x ), vanadium oxide (VO) x It may contain one or more of niobium pentoxide (Nb2O5) and preferably may include tin oxide (SnO2).

[0137] Finally, in steps 2-4 of the method for manufacturing tandem perovskite solar cells according to the present invention, an atomic layer deposition process may be performed to form an electron transport layer on top of the tandem body 20 placed inside the atomic layer deposition process chamber 10.

[0138] Meanwhile, the stacked body 20 may have a structure in which a solar cell, a transparent conductive layer, a hole transport layer and a perovskite light-absorbing layer are stacked in sequence, and an electron transport layer may be formed on top of the perovskite light-absorbing layer by step 2-4 of the method for manufacturing a stacked perovskite solar cell according to the present invention.

[0139] Furthermore, the method for manufacturing tandem perovskite solar cells according to the present invention can satisfy the following condition (1).

[0140] (1) A > B

[0141] In the above condition (1), A represents the temperature inside chamber 10 of atomic layer deposition process, and B represents the temperature of substrate 2 included inside chamber 10 of atomic layer deposition process.

[0142] In this way, by satisfying the conditions (1) of the present invention and forming an electron transport layer, not only is thermal damage minimized and degradation at the interface prevented, but the performance degradation of the perovskite solar cell is also minimized and stability is ensured.

[0143] Specifically, the atomic layer deposition process in steps 2-4 of the method for manufacturing a tandem perovskite solar cell according to the present invention can be performed under the following conditions: the temperature inside chamber 10 of the atomic layer deposition process is 85°C to 150°C, and preferably 85°C to 120°C; and the temperature of the substrate 2 included inside chamber 10 of the atomic layer deposition process is 80°C or lower, preferably 40°C to 70°C, and more preferably 57°C to 63°C. By forming an electron transport layer while meeting these temperature conditions, not only can thermal damage be minimized and interface degradation prevented, but the performance degradation of the perovskite solar cell can also be minimized and stability can be ensured.

[0144] Furthermore, the average thickness of the electron transport layer formed by step 2 of the method for manufacturing tandem perovskite solar cells according to the present invention can be from 3 nm to 20 nm, preferably from 4 nm to 15 nm, and more preferably from 4 nm to 8 nm. If the average thickness is less than 3 nm, it is difficult to form a layer with a uniform thickness, which may lead to a deterioration in electron transport characteristics. If it is greater than 20 nm, not only will the electron transport characteristics decrease, but the series resistance may also increase.

[0145] Next, in step 3 of the method for manufacturing a tandem perovskite solar cell according to the present invention, a transparent electrode and a metal electrode may be sequentially formed on the electron transport layer formed in step 2. In this case, the transparent electrode and the metal electrode are the same as described above.

[0146] Furthermore, the method for manufacturing tandem perovskite solar cells according to the present invention includes steps 1 to 3.

[0147] First, in step 1 of the method for manufacturing a tandem perovskite solar cell according to the present invention, the tandem structure can be manufactured by sequentially forming a transparent conductive layer, a hole transport layer, a perovskite light-absorbing layer, and an intermediate layer on top of the solar cell. In this case, the solar cell, the transparent conductive layer, the hole transport layer, the perovskite light-absorbing layer, and the intermediate layer are the same as described above.

[0148] Next, in step 2 of the method for manufacturing a tandem perovskite solar cell according to the present invention, an electron transport layer can be formed on top of the intermediate layer formed in step 1 by an atomic layer deposition process. As described above, the electron transport layer (ETL) is a layer that transports electrons formed in the perovskite light-absorbing layer while blocking the movement of holes.

[0149] Specifically, step 2 of the atomic layer deposition process in the method for manufacturing tandem perovskite solar cells according to the present invention includes steps 2-1 to 2-4.

[0150] Reference Figure 1 In step 2-1 of the method for manufacturing tandem perovskite solar cells according to the present invention, a chamber 10 for atomic layer deposition (ALD) process in which a substrate 2 is housed can be prepared.

[0151] Next, in step 2-2 of the method for manufacturing a tandem perovskite solar cell according to the present invention, the stack 20 can be placed inside the atomic layer deposition process chamber 10 prepared in step 1, and the stack 20 can be positioned on top of the substrate 2.

[0152] Next, in steps 2-3 of the method for manufacturing tandem perovskite solar cells according to the present invention, material for forming an electron transport layer may be injected into the atomic layer deposition chamber 10.

[0153] In this case, the electron transport layer forming material is a material used to form the electron transport layer via an atomic layer deposition process, and may include materials selected from tin oxide (SnO). x Nickel oxide (NiO) x ), Tin oxide (SnO2), Titanium dioxide (TiO2), Zinc oxide (ZnO), Barium tin oxide (BaSnO3), Niobium hydroxide (NbOH), Hafnium oxide (HfO) x ), zirconium oxide (ZrO x ), vanadium oxide (VO) x It may contain one or more of niobium pentoxide (Nb2O5) and preferably may include tin oxide (SnO2).

[0154] Finally, in steps 2-4 of the method for manufacturing tandem perovskite solar cells according to the present invention, an atomic layer deposition process may be performed to form an electron transport layer on top of the tandem body 20 placed inside the atomic layer deposition process chamber 10.

[0155] Meanwhile, the stacked body 20 may have a structure in which a solar cell, a transparent conductive layer, a hole transport layer, a perovskite light-absorbing layer and an intermediate layer are stacked in sequence, and an electron transport layer may be formed on top of the intermediate layer by step 2-4 of the method for manufacturing a stacked perovskite solar cell according to the present invention.

[0156] Furthermore, the method for manufacturing tandem perovskite solar cells according to the present invention can satisfy the following condition (1).

[0157] (1) A > B

[0158] In the above condition (1), A represents the temperature inside chamber 10 of atomic layer deposition process, and B represents the temperature of substrate 2 included inside chamber 10 of atomic layer deposition process.

[0159] In this way, by satisfying the conditions (1) of the present invention and forming an electron transport layer, not only is thermal damage minimized and degradation at the interface prevented, but the performance degradation of the perovskite solar cell is also minimized and stability is ensured.

[0160] Specifically, the atomic layer deposition process in steps 2-4 of the method for manufacturing a tandem perovskite solar cell according to the present invention can be performed under the following conditions: the temperature inside chamber 10 of the atomic layer deposition process is 85°C to 150°C, and preferably 85°C to 120°C; and the temperature of the substrate 2 included inside chamber 10 of the atomic layer deposition process is 80°C or lower, preferably 40°C to 70°C, and more preferably 57°C to 63°C. By forming an electron transport layer while meeting these temperature conditions, not only can thermal damage be minimized and interface degradation prevented, but the performance degradation of the perovskite solar cell can also be minimized and stability can be ensured.

[0161] Furthermore, the average thickness of the electron transport layer formed by step 2 of the method for manufacturing tandem perovskite solar cells according to the present invention can be from 3 nm to 20 nm, preferably from 4 nm to 15 nm, and more preferably from 4 nm to 8 nm. If the average thickness is less than 3 nm, it is difficult to form a layer with a uniform thickness, which may lead to a deterioration in electron transport characteristics. If it is greater than 20 nm, not only will the electron transport characteristics decrease, but the series resistance may also increase.

[0162] Next, in step 3 of the method for manufacturing a tandem perovskite solar cell according to the present invention, a transparent electrode and a metal electrode may be sequentially formed on top of the electron transport layer formed in step 2. In this case, the transparent electrode and the metal electrode are the same as described above.

[0163] The present invention will be described in more detail below by way of examples, but the following examples do not limit the scope of the invention, but should be interpreted as helpful in understanding the invention.

[0164] Example 1: Fabrication of tandem silicon / perovskite heterojunction solar cells

[0165] (1) Prepare silicon solar cells doped with n-type or p-type impurities (thickness: 180 μm), and remove SiO by hydrofluoric acid treatment. x An oxide film was removed, and residual hydrofluoric acid was removed using ultrapure water. A 20 nm thick transparent conductive layer (ITO) was then formed on top of the silicon solar cell from which the oxide film had been removed using a sputtering process.

[0166] (2) Next, a nickel oxide (NiO) layer with a thickness of 20 nm is deposited on top of the transparent conductive layer by sputtering vacuum deposition. x Furthermore, a hole transport layer is formed by spin-coating a 5 nm thick Me-4PACz onto the top of the deposited nickel oxide.

[0167] (3) Next, a yellow light-absorbing layer solution dissolved in dimethylformamide (DMF) and dimethyl sulfoxide (DMSO) is formed on top of the hole transport layer by spin coating, and a perovskite light-absorbing layer (CSFAPbI) with a thickness of 400 nm and a perovskite crystal structure is formed by heat treatment at 150 °C for 10 minutes. x Br3₋ x (0≤x≤3)).

[0168] (4) Next, lithium fluoride (LiF) with an average thickness of 1 nm is deposited on top of the perovskite light-absorbing layer by vacuum deposition, and C with an average thickness of 15 nm is deposited on top of the deposited lithium fluoride by vacuum deposition. 60 Fullerenes are used to form an intermediate layer, thereby creating a laminate.

[0169] (5) such as Figure 1 As shown, an atomic layer deposition (ALD) chamber 10 is prepared to house a substrate 2, and a stack 20 is placed inside the ALD chamber 10. In this case, the stack 20 is positioned on top of the substrate 2 such that the silicon solar cell of the stack 20 is in contact with the substrate 2. An electron transport layer forming material is injected into the ALD chamber 10, and an ALD process is performed for 15 minutes to form an electron transport layer with an average thickness of 6 nm on top of the stack 20. In this case, the ALD process is performed under the following conditions: the temperature inside the ALD chamber 10 is 110°C, and the temperature of the substrate 2 is 60°C. Furthermore, tin oxide (SnO2) is used as the electron transport layer forming material.

[0170] (6) Next, a 75 nm thick transparent electrode (ITO) is formed on top of the electron transport layer by sputtering.

[0171] (7) Finally, in 1 × 10 -7 Silver (Ag) is deposited to a thickness of 100 nm on top of the transparent electrode under pressure to form a metal electrode, thereby fabricating a tandem silicon / perovskite heterojunction solar cell in which a silicon solar cell, a transparent conductive layer, a hole transport layer, a perovskite light-absorbing layer, an intermediate layer, an electron transport layer, a transparent electrode, and a metal electrode are stacked in sequence.

[0172] Example 2: Fabrication of tandem silicon / perovskite heterojunction solar cells

[0173] A tandem silicon / perovskite heterojunction solar cell was fabricated using the same method as in Example 1. However, unlike Example 1, when forming the electron transport layer using an atomic layer deposition (ALD) chamber, the ALD process was performed under the following conditions: the internal temperature of the ALD chamber was 110°C, and the substrate temperature was 75°C.

[0174] Example 3: Fabrication of tandem silicon / perovskite heterojunction solar cells

[0175] A tandem silicon / perovskite heterojunction solar cell was fabricated using the same method as in Example 1. However, unlike in Example 1, when the electron transport layer was formed using an atomic layer deposition process, the electron transport layer was formed with an average thickness of 10 nm.

[0176] Example 4: Fabrication of tandem silicon / perovskite heterojunction solar cells

[0177] A tandem silicon / perovskite heterojunction solar cell was fabricated using the same method as in Example 2. However, unlike in Example 2, when the electron transport layer was formed using an atomic layer deposition process, the electron transport layer was formed with an average thickness of 10 nm.

[0178] Comparative Example 1: Fabrication of tandem silicon / perovskite heterojunction solar cells

[0179] A tandem silicon / perovskite heterojunction solar cell was fabricated using the same method as in Example 1. However, unlike Example 1, when forming the electron transport layer using an atomic layer deposition (ALD) chamber, the ALD process was performed under the following conditions: the internal temperature of the ALD chamber was 110°C, and the substrate temperature was 110°C.

[0180] Experimental Example 1: Surface SEM Image Analysis of the Electron Transport Layer in a Solar Cell

[0181] In Example 1, during the fabrication of a tandem silicon / perovskite heterojunction solar cell, immediately after the formation of the electron transport layer, an image of the surface of the electron transport layer was captured using a field emission scanning electron microscope (FE-SEM), and the captured FE-SEM image is shown below. Figure 2 In addition, in Comparative Example 1, when fabricating a tandem silicon / perovskite heterojunction solar cell, immediately after forming the electron transport layer, an image of the surface of the electron transport layer was captured using a field emission scanning electron microscope, and the captured FE-SEM image is shown below. Figure 3 middle.

[0182] As in Figure 2 and Figure 3 It can be confirmed that similar grains were observed in the electron transport layer of Example 1 and the electron transport layer of Comparative Example 1. This confirms that when the electron transport layer is formed using an atomic layer deposition process chamber, even under conditions where the temperature inside the atomic layer deposition process chamber is 110°C and the temperature of the substrate is 60°C, the electron transport layer is formed in a similar manner to the conditions where the temperature inside the atomic layer deposition process chamber is 110°C and the temperature of the substrate is 110°C.

[0183] Experimental Example 2: Analysis of the Surface Chemical Properties of the Electron Transport Layer

[0184] The surface chemical properties of the electron transport layer in each of the tandem silicon / perovskite heterojunction solar cells fabricated in Example 1 and Comparative Example 1 were analyzed using photoelectron spectroscopy (XPS), and the results are shown in Table 1 below.

[0185] [Table 1]

[0186]

[0187] As can be confirmed in Table 1 above, compared with the tandem silicon / perovskite heterojunction solar cell manufactured in Comparative Example 1, the tandem silicon / perovskite heterojunction solar cell manufactured in Example 1 exhibits an increased valence band maximum (VBM), a decreased work function (WF), and an increased O / Sn ratio. With the increase in the valence band maximum (VBM) and the decrease in the work function (WF), energy level matching and electron transport characteristics become favorable, which can improve power conversion efficiency through improved open-circuit voltage. Furthermore, it was confirmed that the increased oxygen (O) ratio and the reduction in defect states above the valence band maximum (VBM) enhance hole blocking characteristics.

[0188] Experiment Example 3: Measurement of Solar Cell Performance

[0189] For each of the tandem silicon / perovskite heterojunction solar cells manufactured in Examples 1 to 4 and Comparative Example 1, efficiency was measured using a solar simulation apparatus, a JV Keithley apparatus, and an initial JV curve. After storing the solar cells in a desiccator for 9 days, the JV curve was measured to measure the change in solar cell characteristics after aging, and the results are shown in Table 2 below.

[0190] Table 2

[0191]

[0192] As can be confirmed in Table 2 above, the tandem silicon / perovskite heterojunction solar cell manufactured in Example 1 exhibits the best power conversion efficiency.

[0193] The above description and examples have been illustrated with reference to specific embodiments. However, the present invention is not limited to the above embodiments, and those skilled in the art can make various modifications and implementations without departing from the spirit of the inventive concept described in the appended claims.

Claims

1. A method for forming an electron transport layer for a perovskite solar cell, the method comprising: Step 1: Prepare a chamber for atomic layer deposition process to accommodate the substrate; Step 2: Place the stack in the atomic layer deposition chamber to position the stack on top of the substrate; Step 3: Inject electron transport layer forming material into the chamber used in the atomic layer deposition process; as well as Step 4: Perform atomic layer deposition to form an electron transport layer on top of the stack. Among them, the following condition (1) is met: (1) A > B In condition (1), A represents the temperature inside the chamber for the atomic layer deposition process, and B represents the temperature of the substrate included inside the chamber for the atomic layer deposition process.

2. The method of claim 1, wherein the atomic layer deposition process in step 4 is performed under the following conditions: the temperature inside the atomic layer deposition process chamber is 85°C to 150°C, and the temperature of the substrate included inside the atomic layer deposition process chamber is 80°C or lower.

3. The method of claim 2, wherein the atomic layer deposition process in step 4 is performed under the following conditions: the temperature inside the atomic layer deposition process chamber is 85°C to 120°C, and the temperature of the substrate included inside the atomic layer deposition process chamber is 40°C to 70°C.

4. The method according to claim 1, wherein the stacked body has a structure in which a hole transport layer and a perovskite light absorption layer are sequentially stacked, and The electron transport layer is formed on top of the perovskite light-absorbing layer.

5. The method according to claim 1, wherein the stacked body has a structure in which a hole transport layer, a perovskite light absorption layer and an intermediate layer are sequentially stacked, and The electron transport layer is formed on top of the perovskite light-absorbing layer.

6. The method of claim 5, wherein the intermediate layer comprises a fullerene series organic material.

7. The method according to claim 6, wherein the fullerene series organic materials include those selected from C 60 C 70 One or more of PC60BM and PC70BM.

8. The method of claim 1, wherein the average thickness of the electron transport layer is 3 nm to 20 nm.

9. The method of claim 1, wherein the electron transport layer forming material comprises tin oxide (SnO) selected from... x Nickel oxide (NiO) x Tin oxide (SnO2), titanium dioxide (TiO2), zinc oxide (ZnO), barium tin oxide (BaSnO3), niobium hydroxide (NbOH), hafnium oxide (HfO) x ), zirconium oxide (ZrO x ), vanadium oxide (VO) x One or more of niobium pentoxide (Nb2O5) and niobium pentoxide (Nb2O5).

10. A method for manufacturing a perovskite solar cell, the method comprising: Step 1: A stack is fabricated by forming a perovskite light-absorbing layer on top of the hole transport layer; Step 2: An electron transport layer is formed on top of the perovskite light-absorbing layer using an atomic layer deposition process; as well as Step 3: A transparent electrode and a metal electrode are sequentially formed on top of the electron transport layer. The atomic layer deposition process mentioned above includes: Step 2-1: Prepare a chamber for the atomic layer deposition process to accommodate the substrate; Step 2-2: Place the stack in the atomic layer deposition chamber to position the stack on top of the substrate; Steps 2-3 involve injecting an electron transport layer forming material into the chamber used in the atomic layer deposition process; and Steps 2-4 involve performing atomic layer deposition to form an electron transport layer on top of the perovskite light-absorbing layer. Among them, the following condition (1) is met: (1) A > B In condition (1), A represents the temperature inside the chamber for the atomic layer deposition process, and B represents the temperature of the substrate included inside the chamber for the atomic layer deposition process.

11. A method for manufacturing a perovskite solar cell, the method comprising: Step 1: A stack is fabricated by sequentially forming a perovskite light-absorbing layer and an intermediate layer on top of the hole transport layer; Step 2: An electron transport layer is formed on top of the intermediate layer using an atomic layer deposition process; as well as Step 3: A transparent electrode and a metal electrode are sequentially formed on top of the electron transport layer. The atomic layer deposition process mentioned above includes: Step 2-1: Prepare a chamber for the atomic layer deposition process to accommodate the substrate; Step 2-2: Place the stack in the atomic layer deposition chamber to position the stack on top of the substrate; Steps 2-3 involve injecting an electron transport layer forming material into the chamber used in the atomic layer deposition process; and Steps 2-4 involve performing atomic layer deposition to form an electron transport layer on top of the intermediate layer. Among them, the following condition (1) is met: (1) A > B In condition (1), A represents the temperature inside the chamber for the atomic layer deposition process, and B represents the temperature of the substrate included inside the chamber for the atomic layer deposition process.

12. The method according to claim 10 or 11, wherein the atomic layer deposition process in steps 2-4 is performed under the following conditions: wherein the temperature inside the atomic layer deposition process chamber is 85°C to 150°C, and the temperature of the substrate included inside the atomic layer deposition process chamber is 80°C or lower.

13. A method for manufacturing a tandem perovskite solar cell, the method comprising: Step 1: A stack is fabricated by sequentially forming a transparent conductive layer, a hole transport layer, and a perovskite light-absorbing layer on top of the solar cell. Step 2: An electron transport layer is formed on top of the perovskite light-absorbing layer using an atomic layer deposition process; as well as Step 3: A transparent electrode and a metal electrode are sequentially formed on top of the electron transport layer. The atomic layer deposition process mentioned above includes: Step 2-1: Prepare a chamber for the atomic layer deposition process to accommodate the substrate; Step 2-2: Place the stack in the atomic layer deposition chamber to position the stack on top of the substrate; Steps 2-3 involve injecting an electron transport layer forming material into the chamber used in the atomic layer deposition process; and Steps 2-4 involve performing atomic layer deposition to form an electron transport layer on top of the perovskite light-absorbing layer. Among them, the following condition (1) is met: (1) A > B In condition (1), A represents the temperature inside the chamber for the atomic layer deposition process, and B represents the temperature of the substrate included inside the chamber for the atomic layer deposition process.

14. A method for manufacturing a tandem perovskite solar cell, the method comprising: Step 1: A stacked structure is fabricated by sequentially forming a transparent conductive layer, a hole transport layer, a perovskite light-absorbing layer, and an intermediate layer on the top of the solar cell. Step 2: An electron transport layer is formed on top of the intermediate layer using an atomic layer deposition process; as well as Step 3: A transparent electrode and a metal electrode are sequentially formed on top of the electron transport layer. The atomic layer deposition process mentioned above includes: Step 2-1: Prepare a chamber for the atomic layer deposition process to accommodate the substrate; Step 2-2: Place the stack in the atomic layer deposition chamber to position the stack on top of the substrate; Steps 2-3 involve injecting an electron transport layer forming material into the chamber used in the atomic layer deposition process; and Steps 2-4 involve performing atomic layer deposition to form an electron transport layer on top of the intermediate layer. Among them, the following condition (1) is met: (1) A > B In condition (1), A represents the temperature inside the chamber for the atomic layer deposition process, and B represents the temperature of the substrate included inside the chamber for the atomic layer deposition process.

15. The method according to claim 13 or 14, wherein the atomic layer deposition process in steps 2-4 is performed under the following conditions: wherein the temperature inside the atomic layer deposition process chamber is 85°C to 150°C, and the temperature of the substrate included inside the atomic layer deposition process chamber is 80°C or lower.

16. The method according to claim 13 or 14, wherein the solar cell is a polycrystalline silicon solar cell, a crystalline silicon solar cell, a perovskite solar cell, a gallium arsenide (GaAs) solar cell, a cadmium telluride (CdTe) solar cell, a CIGS (CuInGaSe) solar cell, a CZTS (Cu2ZnSnS4) solar cell, an organic solar cell, a fuel-sensitized solar cell, or a group III-V compound solar cell.

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