Method of forming perovskite compound thin film and method of manufacturing solar cell using the same

Abstract

Provided are a method for forming a perovskite compound thin film and a method for manufacturing a solar cell using the same, the method comprising: a step for supplying a B precursor into a chamber; a step for supplying the X precursor to the chamber for the first time while keeping the power for plasma generation on; and a step for supplying a precursor A, which is formed from at least one compound selected from the group consisting of amine compounds and amidine compounds, into the chamber, the precursor B being formed from an organometallic compound containing a divalent positive ion, the precursor X being formed from a hydrohalide, and the precursor A being formed from at least one compound selected from the group consisting of amine compounds and amidine compounds. The step of supplying the A precursor is performed after the step of supplying the B precursor and the step of supplying the X precursor for the first time.

Description

Technical Field

[0001] The present invention relates to a method for forming a perovskite compound thin film and a method for manufacturing a solar cell using the same. Background Art

[0002] Conventionally, the solution process is mainly used in manufacturing solar cells using perovskite compounds. The solution process is to dissolve the perovskite compound in a predetermined solvent and apply the liquid perovskite compound on a substrate via spin coating, spray coating or slot die.

[0003] This solution process has no problem when applying the perovskite compound to a substrate having a flat surface, but it may be difficult to form a thin film having a uniform thickness when applying the perovskite compound to a crystalline silicon substrate having a pyramid structure for forming a tandem solar cell. Summary of the invention

[0004] Technical issues

[0005] The present invention is to solve the above-mentioned problems and to provide a method for forming a thin film of a perovskite compound using a deposition process (particularly atomic layer deposition) and a method for manufacturing a solar cell using the same.

[0006] Technical Solution

[0007] In order to achieve the above-mentioned purpose, an embodiment of the present invention provides a method for forming a perovskite compound thin film, which includes: a process of supplying a B precursor into a chamber; a process of supplying an X precursor into the chamber for the first time; and a process of supplying an A precursor into the chamber, wherein the B precursor includes an organic metal compound containing a divalent positive ion, the X precursor includes a hydrogen halide, and the A precursor includes at least one compound selected from the group consisting of an amine compound and an amidine compound, wherein the process of supplying the A precursor is performed after the process of supplying the B precursor and the process of supplying the X precursor for the first time.

[0008] The step of supplying the B precursor may include a step of adsorbing the B precursor on the substrate, and the step of supplying the X precursor for the first time may include forming a BX precursor on the substrate by reacting the B precursor with the X precursor. n The step of supplying the A precursor may include providing an intermediate material composed of BX n The intermediate material composed of (n<3) compounds reacts with the A precursor to form ABX on the substrate nA may include at least one monovalent organic cation selected from the group consisting of monovalent organic cations of amine compounds and monovalent organic cations of amidine compounds, B may include a divalent cation, and X may include a halogen compound.

[0009] The method for forming a perovskite compound thin film may further include a blowing process performed in at least one of a period between a process of supplying a B precursor and a process of supplying an X precursor for the first time, a period between a process of supplying an X precursor for the first time and a process of supplying an A precursor, and a period after the process of supplying an A precursor.

[0010] The method of forming a perovskite compound thin film may further include a process of supplying an X precursor into the chamber for a second time after the process of supplying the A precursor.

[0011] The process of supplying the X precursor into the chamber for the second time may include a process of applying power to form plasma.

[0012] The method for forming a perovskite compound thin film may further include a blowing process performed in at least one of a period between a process of supplying a B precursor and a process of supplying an X precursor for the first time, a period between a process of supplying an X precursor for the first time and a process of supplying an A precursor, a period between a process of supplying an A precursor and a process of supplying an X precursor for the second time, and a period after supplying an X precursor for the second time.

[0013] The process of supplying the B precursor may include a process of allowing the B precursor to be adsorbed on the substrate, wherein the process of supplying the X precursor for the first time may include forming a BX precursor on the substrate by reacting the B precursor with the X precursor. n (n<3) compounds, wherein the step of supplying the A precursor may include providing a precursor composed of BX n The primary intermediate material composed of (n<3) compounds reacts with the A precursor to form ABX on the substrate. n (n<3) compound, wherein the second step of supplying X precursor may include the step of making ABX n A step of reacting a secondary intermediate material composed of a (n<3) compound with an X precursor to form an ABX3 compound on a substrate, wherein A may include at least one monovalent organic cation selected from the group consisting of monovalent organic cations of amine compounds and monovalent organic cations of amidine compounds, B may include a divalent cation, and X may include a halogen compound.

[0014] The method for forming a perovskite compound thin film may further include a step of supplying a C precursor into the chamber during the step of supplying the B precursor, wherein the C precursor may include at least one alkali metal compound.

[0015] The process of supplying the B precursor and the C precursor may include a process of adsorbing the B precursor and the C precursor on the substrate, wherein the process of supplying the X precursor for the first time may include forming a CBX on the substrate by reacting the B precursor and the C precursor with the X precursor. n (n<3) intermediate material composed of compounds, wherein the step of supplying the A precursor may include: n The intermediate material composed of (n<3) compounds reacts with the A precursor to form CABX on the substrate n A process for preparing a monovalent organic cation (n<3) compound, wherein A may include at least one monovalent organic cation selected from the group consisting of monovalent organic cations of amine compounds and monovalent organic cations of amidine compounds, B may include a divalent cation, C precursor may include an alkali metal, and X may include a halogen compound.

[0016] The method of forming a perovskite compound thin film may further include a step of supplying a crystal control material into the chamber between the step of supplying the X precursor for the first time and the step of supplying the A precursor.

[0017] The crystal control material may comprise pyridine or a pyridine derivative.

[0018] The process of supplying the X precursor into the chamber for the first time may include a process of applying power to form plasma.

[0019] Another embodiment of the present invention provides a method for forming a perovskite compound film, comprising a process of supplying a B precursor and a C precursor into a chamber; and a process of supplying an X precursor into the chamber for the first time, wherein the B precursor comprises an organic metal compound containing a divalent positive ion, the C precursor comprises at least one alkali metal compound, and the X precursor comprises a hydrogen halide, wherein the process of supplying the X precursor for the first time is performed after the process of supplying the B precursor and the C precursor.

[0020] Another embodiment of the present invention provides a method for forming a perovskite compound film, comprising: a process of supplying a C precursor into a chamber; a process of supplying a B precursor into the chamber; and a process of supplying an X precursor into the chamber for the first time, wherein the B precursor comprises an organic metal compound containing a divalent positive ion, the C precursor comprises at least one alkali metal compound, and the X precursor comprises a hydrogen halide, wherein the process of supplying the C precursor is performed before the process of supplying the B precursor and the process of supplying the X precursor for the first time.

[0021] Another embodiment of the present invention provides a method for manufacturing a solar cell, comprising: forming a crystalline solar cell; forming a buffer layer on the crystalline solar cell; forming a perovskite solar cell on the buffer layer; and forming a first electrode on the perovskite solar cell and forming a second electrode on the crystalline solar cell, wherein forming the perovskite solar cell comprises the method of forming a perovskite compound thin film as described above.

[0022] Beneficial Effects

[0023] According to the present invention, the following effects can be achieved.

[0024] According to the embodiment of the present invention, since the perovskite compound is formed by atomic layer deposition, a tandem solar cell can be easily formed by coating the perovskite compound on a crystalline silicon substrate having a concavo-convex structure.

[0025] According to an embodiment of the present invention, a perovskite compound of ABX3 may be easily prepared by performing the A precursor supplying process after the B precursor supplying process and the X precursor supplying process.

[0026] According to an embodiment of the present invention, since BX is formed n The A precursor supply process is performed after the intermediate material (n≤3), so the compound A of the A precursor is not exposed to the plasma, so that BX can be made without destroying the chemical bond of the compound A of the A precursor. n The intermediate material (n≤3) reacts with the A precursor.

[0027] According to an embodiment of the present invention, an X precursor is first supplied to form BX n (n<3) primary intermediate material of the compound, supplying A precursor to form ABX n The secondary intermediate material of the (n<3) compound is then supplied with an X precursor for a secondary time to form a perovskite compound film of ABX3, thereby making it possible to more flexibly adjust the processing conditions in the vacuum chamber.

[0028] According to an embodiment of the present invention, during the secondary supply process of the X precursor, when the power used for plasma formation is kept in an off state, ABX can be prevented from n The chemical bonds of compound A in the secondary intermediate material of (n<3) are broken. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 is a flowchart showing a process of forming a perovskite compound thin film according to an embodiment of the present invention.

[0030] Figure 2 FIG. 4 is a flowchart showing a process of forming a perovskite compound thin film according to another embodiment of the present invention.

[0031] Figure 3 FIG. 4 is a flowchart showing a process of forming a perovskite compound thin film according to another embodiment of the present invention.

[0032] Figure 4 FIG. 4 is a flowchart showing a process of forming a perovskite compound thin film according to another embodiment of the present invention.

[0033] Figure 5 FIG. 4 is a flowchart showing a process of forming a perovskite compound thin film according to another embodiment of the present invention.

[0034] Figure 6 FIG. 4 is a flowchart showing a process of forming a perovskite compound thin film according to another embodiment of the present invention.

[0035] Figure 7 FIG. 4 is a flowchart showing a process of forming a perovskite compound thin film according to another embodiment of the present invention.

[0036] Figure 8 FIG. 4 is a flowchart showing a process of forming a perovskite compound thin film according to another embodiment of the present invention.

[0037] Fig. 9 FIG. 4 is a flowchart showing a process of forming a perovskite compound thin film according to another embodiment of the present invention.

[0038] Fig.10 FIG. 4 is a flowchart showing a process of forming a perovskite compound thin film according to another embodiment of the present invention.

[0039] Fig.11 FIG. 4 is a flowchart showing a process of forming a perovskite compound thin film according to another embodiment of the present invention.

[0040] Fig.12 FIG. 4 is a flowchart showing a process of forming a perovskite compound thin film according to another embodiment of the present invention.

[0041] Fig.13a is a diagram showing the crystal properties of a perovskite compound thin film prepared according to an embodiment of the present invention, Fig.13b is a diagram showing the crystal properties of a perovskite compound thin film prepared according to another embodiment of the present invention.

[0042] Figures 14a to 14e 1 is a cross-sectional view showing the steps of a method for manufacturing a solar cell according to an embodiment of the present invention. DETAILED DESCRIPTION

[0043] The advantages and features of the present invention and the implementation method of the present invention will be explained by the embodiments described below with reference to the accompanying drawings. However, the present invention can be embodied in different forms and should not be understood as being limited to the embodiments set forth herein. Rather, these embodiments are provided so that the present invention will be thorough and complete, and will fully convey the scope of the present invention to those skilled in the art. In addition, the present invention is limited only by the scope of the claims.

[0044] The shapes, sizes, proportions, angles and quantities disclosed in the accompanying drawings for describing the embodiments of the present invention are only examples, and therefore the present invention is not limited to the details shown. Throughout the application, similar reference numerals represent similar elements. In the following description, when it is determined that the detailed description of the relevant known technology will unnecessarily obscure the focus of the present invention, such detailed description will be omitted. In the case of using "including", "having" and "comprising" described in this specification, unless "only" is used, another component can be added. Unless otherwise specified, the term in the singular form may include the plural form.

[0045] When explaining an element, although the error range is not described in detail, the element should be understood as including the error range.

[0046] When describing a positional relationship, for example, when the positional relationship between two components is described as "on", "above", "under", and "beside", unless "immediately" or "directly" is used, one or more other components may be arranged between the two components.

[0047] When describing a time relationship, for example, when describing a time sequence with "after," "subsequently," "next," and "before," discontinuous cases may be included unless "just" or "directly" is used.

[0048] It will be understood that, although the terms "first", "second", etc. can be used to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another element. For example, without departing from the scope of the present invention, the first element can be named as the second element, and similarly, the second element can be named as the first element.

[0049] The term "at least one" should be understood to include any and all combinations of more than one of the listed items. For example, the meaning of "at least one of the first, second, and third items" means a combination of more than two of the first, second, and third items and all items proposed by the first, second, or third items.

[0050] The features of the various embodiments of the present invention may be combined or combined with each other in part or in whole, and may interact with each other in various ways and be technically driven in a manner that can be fully understood by those skilled in the art. The embodiments of the present invention may be implemented independently of each other, or may be implemented in a mutually dependent relationship.

[0051] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0052] Figure 1 is a flowchart showing a process of forming a perovskite compound thin film according to an embodiment of the present invention.

[0053] like Figure 1 As shown, a thin film of the perovskite compound ABX3 according to an embodiment of the present invention can be formed by atomic layer deposition (ALD) in a vacuum chamber. Specifically, the atomic layer deposition (ALD) includes a process S10 of supplying a B precursor, a first blowing process S20, a process S30 of supplying an X precursor while the power used for plasma formation is kept in an on state, a second blowing process S40, a process S50 of supplying an A precursor, and a third blowing process S60.

[0054] The process S10 of supplying the B precursor includes a process of supplying the B precursor onto the substrate so that the B precursor is adsorbed on the substrate while the substrate is loaded into the vacuum chamber.

[0055] The B precursor may include an organometallic compound containing a divalent positive ion, and B may include a divalent positive ion.

[0056] The organometallic compound including a divalent positive ion may include a metal selected from the group consisting of lead (Pb), tin (Sn), germanium (Ge), antimony (Sb), bismuth (Bi), and barium (Ba).

[0057] In detail, the organometallic compound including a divalent positive ion may include a compound represented by the following Chemical Formula 1:

[0058] Chemical formula 1

[0059]

[0060] (In Chemical Formula 1, R 1 To R 12 Each independently consists of hydrogen or alkyl, and X is selected from the group consisting of Pb, Sn, Ge, Sb, Bi and Ba. )

[0061] Alternatively, the organometallic compound containing a divalent cation may be selected from the group consisting of Pb(CH3)4, Pb(C2H5)4, Pb(SCN)2, (C2H5)3PbOCH2C(CH3)3, Pb(C11 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 The group composed of N2O2Pb.

[0062] The first purge process S20 may include a removal process of removing the residual B precursor that is not adsorbed on the substrate by supplying a first purge gas into the vacuum chamber.

[0063] The process S30 of supplying the X precursor while the power for plasma formation is kept on may include supplying the X precursor into the vacuum chamber so that the B precursor adsorbed on the substrate reacts with the supplied X precursor to form an intermediate material of the BX3 compound on the substrate.

[0064] The X precursor may comprise a hydrohalide and X may comprise a halogen compound. The hydrohalide may be selected from the group consisting of HI, HBr, HF and HCl. In some cases, the X precursor may be supplied while the power for plasma formation is maintained in an off state rather than an on state. The power for plasma formation may be applied only to a portion of the process period for supplying the X precursor.

[0065] The second purge process S40 may include a process of supplying a second purge gas into the vacuum chamber to remove the X precursor that has not reacted and remains on the substrate. The second purge gas may be the same as the first purge gas, but in some cases, may be different from the first purge gas.

[0066] The process S50 of supplying the A precursor may include a process of supplying the A precursor into the vacuum chamber so that the BX3 compound formed on the substrate reacts with the A precursor, thereby forming a perovskite compound thin film of the ABX3 compound on the substrate.

[0067] The A precursor may include at least one compound selected from the group consisting of an amine compound and an amidine compound. A may consist of a monovalent organic cation of an amine compound, a monovalent organic cation of an amidine compound, or a monovalent organic cation of an amine compound and a monovalent organic cation of an amidine compound. A may have a structure in which a monovalent organic cation of an amine compound is contained in an x ​​ratio and a monovalent organic cation of an amidine compound is contained in a y ratio. In this case, each of x and y is greater than 0, and x+y=1.

[0068] The amine compound may be selected from the group consisting of methylamine, ethylamine and phenethylamine. The amidine compound may consist of formamidine.

[0069] The third purge process S60 may include a process of removing the unreacted precursor A on the substrate by supplying a third purge gas into the vacuum chamber. The third purge gas may be the same as the first purge gas or the second purge gas, but in some cases, may be different from the first purge gas or the second purge gas.

[0070] Precursor A, Precursor B, and Precursor X are composed of materials that evaporate at a temperature in the range of room temperature to 200° C. (preferably, at a temperature in the range of 50° C. to 150° C.). Therefore, the process of manufacturing the ABX3 perovskite compound by atomic layer deposition (ALD) can be performed at a temperature below 200° C. (preferably, below 150° C.). Therefore, during the ALD process, decomposition of organic substances in the finally obtained ABX3 compound can be prevented.

[0071] According to an embodiment of the present invention, the A precursor supplying step S50 is performed after the B precursor supplying step S10 and the X precursor supplying step S30. Therefore, the perovskite compound of ABX3 can be easily prepared by first forming an intermediate material composed of a BX3 compound on a substrate and then reacting the above-mentioned BX3 compound with the A precursor.

[0072] If the A precursor supplying step S50 is performed before the B precursor supplying step S10 to first form an intermediate material composed of the AX3 compound on the substrate and then react the AX3 compound with the B precursor, the ABX3 perovskite compound cannot be easily obtained. This is because the reaction between the AX3 compound and the precursor B does not proceed smoothly.

[0073] In addition, if the A precursor supplying step S50 is performed before the B precursor supplying step S10, and then the step S30 of supplying the X precursor is performed while the power for plasma formation is kept on, the chemical bonds of the compound A composed of organic materials in the A precursor are destroyed by the plasma, so that the AX3 intermediate material cannot be easily obtained, and the final ABX3 perovskite compound cannot be easily obtained.

[0074] On the other hand, according to an embodiment of the present invention, since the A precursor supplying step S50 is performed after the BX3 intermediate material is formed, the compound A in the A precursor is not exposed to plasma. Therefore, the A precursor reacts with the ABX3 perovskite compound without breaking the chemical bond of the compound A of the A precursor, thereby easily obtaining the final ABX3 perovskite compound.

[0075] Figure 2 FIG. 4 is a flowchart showing a process of forming a perovskite compound thin film according to another embodiment of the present invention.

[0076] like Figure 2 As shown, a perovskite compound (ABX3) thin film according to another embodiment of the present invention can be formed by atomic layer deposition (ALD) in a vacuum chamber. Specifically, the atomic layer deposition (ALD) includes a process S10 of supplying a B precursor, a first blowing process S20, a process S30 of supplying an X precursor for the first time while the power for plasma formation is kept in an on state, a second blowing process S40, a process S50 of supplying an A precursor, a third blowing process S60, a process S70 of supplying an X precursor for the second time while the power for plasma formation is kept in an on state or an off state, and a fourth blowing process S80.

[0077] Because the step S10 of supplying the B precursor and the first blowing step S20 are Figure 1 The process S10 of supplying the B precursor and the first blowing process S20 are the same, so the repeated description thereof will be omitted.

[0078] The process S30 of supplying the X precursor for the first time while the power for plasma formation is kept in the on state may include supplying the X precursor into the vacuum chamber and reacting the B precursor adsorbed on the substrate with the supplied X precursor to form a BX precursor on the substrate. n (n<3) The process of producing a primary intermediate material composed of compounds.

[0079] Because X precursor and compound X Figure 1 The X precursor and the compound X are the same, so a repeated description thereof will be omitted.

[0080] Because the second blowing step S40 and Figure 1 The second blowing process S40 is the same as that of the embodiment of the present invention, so a repeated description thereof will be omitted.

[0081] The step S50 of supplying the A precursor may include supplying the A precursor into a vacuum chamber and causing the BX formed on the substrate to n The (n<3) compound reacts with the supplied A precursor to form a ABX n (n<3) The process of producing a secondary intermediate material composed of compounds.

[0082] Because the A precursor and compound A are the same as above Figure 1 The A precursor is the same as compound A, so a repeated description thereof will be omitted.

[0083] The third purge process S60 may include a process of removing the unreacted precursor A on the substrate by supplying a third purge gas into the vacuum chamber. The third purge gas may be the same as the first purge gas or the second purge gas, but in some cases, may be different from the first purge gas or the second purge gas.

[0084] The process S70 of supplying the X precursor for the second time while the power for plasma formation is kept in the on state or the off state may include supplying the X precursor into the vacuum chamber and causing the ABX formed on the substrate to n The (n<3) compound reacts with the X precursor supplied for the second time to form an ABX3 perovskite compound thin film on the substrate.

[0085] The X precursor in step S70 may be the same as or different from the X precursor in step S30.

[0086] The fourth purge process S80 may include a process of supplying a fourth purge gas into the vacuum chamber to remove the X precursor that has not reacted and remains on the substrate. The fourth purge gas may be the same as the first purge gas, the second purge gas, or the third purge gas, but in some cases, may be different from the first purge gas, the second purge gas, or the third purge gas.

[0087] According to another embodiment of the present invention, the X precursor is first supplied to form BX n (n<3) primary intermediate material of the compound, supplying A precursor to form ABX n (n<3) compound, and then supplying the X precursor a second time to form an ABX3 perovskite compound film, thereby more flexibly controlling the processing conditions in the vacuum chamber.

[0088] On the other hand, in step S50 of supplying the precursor A, a layer of ABX is formed on the substrate. n Since the compound A composed of an organic material is chemically bonded to the compound B and the compound X, the chemical bonds in the compound A are not easily broken even when the power for plasma formation is turned on in the second supplying process S70 of the X precursor. Therefore, during the second supplying process S70 of the X precursor, the power for plasma formation can be kept turned on.

[0089] However, during the second supply step S70 of the X precursor, in order to prevent the n Since the chemical bonds of the compound A in the secondary intermediate material composed of the (n<3) compound are broken, it is desirable to keep the power for plasma formation in an OFF state during the second supplying step S70 of the X precursor.

[0090] Figure 3 FIG. 4 is a flowchart showing a process of forming a perovskite compound thin film according to another embodiment of the present invention.

[0091] like Figure 3 As shown, a perovskite compound (ABX3) thin film according to another embodiment of the present invention can be formed by atomic layer deposition (ALD) in a vacuum chamber. Specifically, the atomic layer deposition (ALD) includes a process S10 of supplying a B precursor and a C precursor, a first blowing process S20, a process S30 of supplying an X precursor for the first time while the power used for plasma formation is kept in an on state, a second blowing process S40, a process S50 of supplying an A precursor, and a third blowing process S60.

[0092] The process S10 of supplying the B precursor and the C precursor includes a process of supplying the B precursor and the C precursor on the substrate while the substrate is loaded into the vacuum chamber so that the B precursor and the C precursor are adsorbed on the substrate.

[0093] The B precursor and the C precursor can be supplied simultaneously.

[0094] Because B precursor and compound B Figure 1 The B precursor is the same as compound B, so a repeated description thereof will be omitted.

[0095] The C precursor may include at least one alkali metal compound. Compound C may include at least one alkali metal, such as cesium (Cs).

[0096] The alkali metal-based compound may include a compound represented by the following Chemical Formula 2:

[0097] Chemical formula 2

[0098]

[0099] (In Chemical Formula 2, R 1 To R 6 Each independently consists of hydrogen or an alkyl group, and Y is an alkali metal. )

[0100] As described above, according to another embodiment of the present invention, at least one alkali metal compound is added to the reactants to compensate for the unstable characteristics of the monovalent organic positive ions that are susceptible to water, heat and plasma.

[0101] The first purge process S20 may include a process of removing the B precursor and the C precursor remaining without being adsorbed on the substrate by supplying a first purge gas into the vacuum chamber.

[0102] The process S30 of supplying the X precursor while the power for plasma formation is kept in an on state may include a step of supplying the X precursor into the vacuum chamber so that the B precursor and the C precursor adsorbed on the substrate react with the supplied X precursor to form an intermediate material of the CBX3 compound on the substrate.

[0103] X precursor and compound X and Figure 1 The X precursor and compound X are the same.

[0104] The second blowing step S40 and Figure 1 The second blowing step S40 is the same.

[0105] The process S50 of supplying the A precursor may include a process of supplying the A precursor into the vacuum chamber so that the CBX3 compound formed on the substrate reacts with the A precursor to form a perovskite compound thin film of the CABX3 compound on the substrate.

[0106] A precursor and compound A and Figure 1 The A precursor is the same as compound A.

[0107] CA may have a structure in which a monovalent organic positive ion of an amine compound is contained in an x ​​ratio, a monovalent organic positive ion of an amidine compound is contained in an y ratio, and a monovalent positive ion of an alkali metal is contained in an z ratio. In this case, each of x, y, and z is greater than 0, and x+y+z=1.

[0108] The third purge process S60 may include a process of removing the unreacted precursor A on the substrate by supplying a third purge gas into the vacuum chamber. The third purge gas may be the same as the first purge gas or the second purge gas, but in some cases, may be different from the first purge gas or the second purge gas.

[0109] Figure 4 FIG. 4 is a flowchart showing a process of forming a perovskite compound thin film according to another embodiment of the present invention.

[0110] like Figure 4 As shown, a perovskite compound (ABX3) thin film according to another embodiment of the present invention can be formed by atomic layer deposition (ALD) in a vacuum chamber. Specifically, the atomic layer deposition (ALD) includes a process S10 of supplying a B precursor and a C precursor, a first blowing process S20, a process S30 of supplying an X precursor for the first time while the power for plasma formation is kept in an on state, a second blowing process S40, a process S50 of supplying an A precursor, a third blowing process S60, a process S70 of supplying an X precursor for the second time while the power for plasma formation is kept in an on state or an off state, and a fourth blowing process S80.

[0111] Since the step S10 of supplying the B precursor and the C precursor and the first blowing step S20 are Figure 3 The step S10 of supplying the B precursor and the C precursor and the first blowing step S20 in FIG. 1 are the same, so repeated descriptions thereof will be omitted.

[0112] The process S30 of supplying the X precursor for the first time while the power for plasma formation is kept in the on state may include supplying the X precursor into the vacuum chamber and reacting the B precursor and the C precursor adsorbed on the substrate with the supplied X precursor to form a CBX on the substrate. n (n<3) primary intermediate material composed of compounds.

[0113] Because X precursor and compound X Figure 3 The X precursor and the compound X are the same, so a repeated description thereof will be omitted.

[0114] Because the second blowing step S40 and Figure 3 The second blowing process S40 is the same as that of the embodiment of the present invention, so a repeated description thereof will be omitted.

[0115] The step S50 of supplying the A precursor may include supplying the A precursor into a vacuum chamber and causing the CBX formed on the substrate to n The (n<3) compound reacts with the supplied A precursor to form a CABX n (n<3) The process of producing a secondary intermediate material composed of compounds.

[0116] Because the A precursor and compound A are the same as above Figure 3 The A precursor is the same as compound A, so a repeated description thereof will be omitted.

[0117] The third purge process S60 may include a process of removing the unreacted precursor A on the substrate by supplying a third purge gas into the vacuum chamber. The third purge gas may be the same as the first purge gas or the second purge gas, but in some cases, may be different from the first purge gas or the second purge gas.

[0118] The process S70 of supplying the X precursor for the second time while the power for plasma formation is kept in the on state or the off state may include supplying the X precursor into the vacuum chamber and causing the CABX formed on the substrate to n The (n<3) compound reacts with the X precursor supplied for the second time to form a CABX3 perovskite compound thin film on the substrate.

[0119] The X precursor in step S70 may be the same as or different from the X precursor in step S30.

[0120] The fourth purge process S80 may include a process of supplying a fourth purge gas into the vacuum chamber to remove the X precursor that has not reacted and remains on the substrate. The fourth purge gas may be the same as the first purge gas, the second purge gas, or the third purge gas, but in some cases, may be different from the first purge gas, the second purge gas, or the third purge gas.

[0121] According to another embodiment of the present invention, the X precursor is first supplied to form CBX n (n<3) primary intermediate material of compound, supplying A precursor to form CABX n (n<3) compound, and then supplying the X precursor a second time to form a CABX3 perovskite compound film, thereby more flexibly controlling the processing conditions in the vacuum chamber.

[0122] On the other hand, a CABX film is formed on the substrate by supplying the precursor A in step S50. n Since the compound A composed of an organic material is chemically bonded to the compound C, the compound B, and the compound X, the chemical bonds in the compound A are not easily broken even when the power for plasma formation is turned on in the second supplying process S70 of the X precursor. Therefore, during the second supplying process S70 of the X precursor, the power for plasma formation can be kept turned on.

[0123] However, during the second supply step S70 of the X precursor, in order to prevent the n Since the chemical bonds of the compound A in the second intermediate material composed of the (n<3) compound are broken, it is desirable to keep the power for plasma formation in an OFF state during the second supplying step S70 of the X precursor.

[0124] Figure 5 FIG. 4 is a flowchart showing a process of forming a perovskite compound thin film according to another embodiment of the present invention.

[0125] Figure 5 With the above Figure 1 The difference is that between the second purge step S40 and the A precursor supply step S50 , a pyridine supply step S43 and a third purge step S46 are additionally performed.

[0126] According to another embodiment of the present invention, the crystal properties of the finally obtained ABX3 compound can be improved by supplying pyridine or a pyridine derivative to an intermediate material composed of a BX3 compound and then supplying a precursor A. In the following description, pyridine or a pyridine derivative is collectively referred to as pyridine.

[0127] The pyridine derivative may include, but is not limited to, 4-methylpyridine or 4-tert-butylpyridine.

[0128] In addition to pyridine, a crystal control material or a growth control material of a perovskite compound of an ABX3 compound may be additionally supplied. The crystal control material or the growth control material may improve crystal stability by removing dangling bonds in the crystal via a passivation effect.

[0129] exist Figure 5 In the third blowing step S46, the third blowing gas may be supplied into the vacuum chamber to remove the pyridine or pyridine derivative remaining on the substrate. Figure 5 In the embodiment, since the third blowing step S46 is added, the blowing step S50 performed after the step of supplying the A precursor becomes the fourth blowing step S60.

[0130] Figure 6 FIG. 4 is a flowchart showing a process of forming a perovskite compound thin film according to another embodiment of the present invention.

[0131] Figure 6 With the above Figure 2 The difference is that between the second purge step S40 and the A precursor supply step S50 , a pyridine supply step S43 and a third purge step S46 are additionally performed.

[0132] exist Figure 6 In the embodiment, the third purge process S46 may include a process of removing pyridine or a pyridine derivative remaining on the substrate by supplying a third purge gas into the vacuum chamber.

[0133] In addition, Figure 6 In the embodiment, since the third blowing step S46 is added, the blowing step performed after the step S50 of supplying the A precursor becomes the fourth blowing step S60, and the blowing step performed after the step S70 of supplying the X precursor for the second time while the power used for plasma formation is kept in the on state or the off state becomes the fifth blowing step S80.

[0134] Figure 7 FIG. 4 is a flowchart showing a process of forming a perovskite compound thin film according to another embodiment of the present invention.

[0135] Figure 7 With the above Figure 3 The difference is that between the second purge step S40 and the A precursor supply step S50 , a pyridine supply step S43 and a third purge step S46 are additionally performed.

[0136] exist Figure 7In the embodiment, the third purge process S46 may include a process of removing pyridine or a pyridine derivative remaining on the substrate by supplying a third purge gas into the vacuum chamber.

[0137] In addition, Figure 7 In the embodiment, since the third blowing step S46 is added, the blowing step performed after the step S50 of supplying the A precursor becomes the fourth blowing step S60.

[0138] Figure 8 FIG. 4 is a flowchart showing a process of forming a perovskite compound thin film according to another embodiment of the present invention.

[0139] Figure 8 With the above Figure 4 The difference is that between the second purge step S40 and the A precursor supply step S50 , a pyridine supply step S43 and a third purge step S46 are additionally performed.

[0140] exist Figure 8 In the embodiment, the third purge process S46 may include a process of removing pyridine or a pyridine derivative remaining on the substrate by supplying a third purge gas into the vacuum chamber.

[0141] In addition, Figure 8 In the embodiment, since the third blowing step S46 is added, the blowing step performed after the step S50 of supplying the A precursor becomes the fourth blowing step S60, and the blowing step performed after the step S70 of supplying the X precursor for the second time while the power used for plasma formation is kept in the on state or the off state becomes the fifth blowing step S80.

[0142] Fig. 9 FIG. 4 is a flowchart showing a process of forming a perovskite compound thin film according to another embodiment of the present invention.

[0143] like Fig. 9 As shown, a perovskite compound (CBX3) thin film according to another embodiment of the present invention can be formed in a vacuum chamber by atomic layer deposition (ALD). Specifically, the atomic layer deposition (ALD) includes a process S10 of supplying a B precursor and a C precursor, a first blowing process S20, a process S30 of supplying an X precursor while the power used for plasma formation is kept in an on state, and a second blowing process S40.

[0144] Since each process is the same as the above-mentioned process, repeated description will be omitted. The same is true for the following embodiments.

[0145] Fig.10 is a flowchart showing a process of forming a perovskite compound thin film according to an embodiment of the present invention.

[0146] like Fig.10 As shown, a thin film of the perovskite compound CBX3 according to an embodiment of the present invention can be formed by atomic layer deposition (ALD) in a vacuum chamber. Specifically, the atomic layer deposition (ALD) includes a process S10 of supplying a C precursor, a first blowing process S20, a process S30 of supplying a B precursor, a second blowing process S40, a process S50 of supplying an X precursor while the power used for plasma formation is kept in an on state, and a third blowing process S60.

[0147] Fig.11 is a flowchart showing a process of forming a perovskite compound thin film according to an embodiment of the present invention.

[0148] like Fig.11 As shown, a thin film of the perovskite compound CBX3 according to an embodiment of the present invention can be formed by atomic layer deposition (ALD) in a vacuum chamber. Specifically, the atomic layer deposition (ALD) includes a process S10 of supplying a B precursor and a C precursor, a first blowing process S20, a process S30 of supplying an X precursor while the power used for plasma formation is kept in an on state, a second blowing process S40, a process S50 of supplying pyridine, and a third blowing process S60.

[0149] Fig.12 is a flowchart showing a process of forming a perovskite compound thin film according to an embodiment of the present invention.

[0150] like Fig.12 As shown, a thin film of a perovskite compound CBX3 according to an embodiment of the present invention can be formed by atomic layer deposition (ALD) in a vacuum chamber. Specifically, the atomic layer deposition (ALD) includes a process S10 of supplying a C precursor, a first blowing process S20, a process S30 of supplying a B precursor, a second blowing process S40, a process S50 of supplying an X precursor while the power used for plasma formation is kept in an on state, a third blowing process S60, a process S70 of supplying pyridine, and a fourth blowing process S80.

[0151] Figures 9 to 12 The embodiment may further include, after each purge process, a process of supplying an X precursor while power for plasma formation is maintained in an on state or an off state and a subsequent purge process.

[0152] Fig.13a is a diagram showing the crystal properties of a perovskite compound thin film prepared according to an embodiment of the present invention, Fig.13b is a diagram showing the crystal properties of a perovskite compound thin film prepared according to another embodiment of the present invention.

[0153] In FIG. 13a and FIG. 13b, the X-axis represents the angle of the light beam irradiation, and the Y-axis represents the size of the crystal.

[0154] in particular, Fig.13a It is shown that according to Figure 2 Figure 2 shows the crystal properties of the perovskite compound thin film prepared by the process of Fig.13b It is shown that according to Figure 6 Figure 2 shows the crystalline properties of the perovskite compound thin films prepared by the process.

[0155] Specifically, Fig.13a The crystal properties of the perovskite compound of MAPbl3 prepared by supplying Pb(C2H5)4 as a B precursor, performing a first purge, supplying HI as an X precursor for the first time while the power for plasma formation is kept on to form PbI2 on a substrate, performing a second purge, supplying methylamine (MA) as an A precursor to form MAPbI2 on the substrate, performing a third purge, supplying HI as an X precursor for the second time while the power for plasma formation is kept on to form MAPbI3 on ​​the substrate, and performing a fourth purge are shown.

[0156] Fig.13b The crystal properties of the perovskite compound of MAPbl3 prepared by supplying Pb(C2H5)4 as a B precursor, performing a first purge, supplying HI as an X precursor for the first time while the power for plasma formation is kept on to form Pbl2 on a substrate, performing a second purge, supplying pyridine, performing a third purge, supplying methylamine (MA) as an A precursor to form MAPbl2 on a substrate, performing a fourth purge, supplying HI as an X precursor for the second time while the power for plasma formation is kept on to form MAPbI3 on ​​a substrate, and performing a fifth purge are shown.

[0157] In accordance with Fig.13a In the case of the prepared perovskite compound, the direction (110) as the crystal growth direction is the main peak, but additional peaks also grow, so the characteristic of the crystal growth direction being arranged in one direction is reduced, and the characteristics of amorphous characteristics are shown in the range of 10° to 40°.

[0158] On the other hand, according to Fig.13b In the case of the prepared perovskite compound, the crystal growth direction (110) is the main peak and the additional peak hardly grows, which means that the property of arranging the crystal growth direction in one direction is improved.

[0159] In particular, Fig.13bIn the graph, the peak is formed larger, which means that the crystal is formed larger. When the crystal is formed larger in this way, the occurrence rate of loss between crystals is low and the conductivity is excellent.

[0160] Figures 14a to 14e 1 is a process cross-sectional view showing a method of manufacturing a solar cell according to an embodiment of the present invention.

[0161] First, if Fig.14a As shown, a crystalline solar cell 100 is manufactured.

[0162] The crystalline solar cell 100 is manufactured by a process of etching one surface and the other surface of a semiconductor substrate 110, such as a wafer, to form a concave-convex structure, doping a specific dopant on the one surface of the semiconductor substrate 110 to form a first semiconductor layer 120, and doping a specific dopant on the other surface of the semiconductor substrate 110 to form a second semiconductor layer 130.

[0163] Since the one surface and the other surface of the semiconductor substrate 110 are formed in the concavo-convex structure, the first semiconductor layer 120 and the second semiconductor layer 130 are formed in shapes corresponding to the concavo-convex structure.

[0164] On the other hand, the drawings show that both the one surface and the other surface of the semiconductor substrate 110 are formed into a concavo-convex structure, but it is not necessarily limited to this. The one surface of the semiconductor substrate 110 may be formed into a concavo-convex structure, and the other surface may be formed into a flat structure. Alternatively, the other surface of the semiconductor substrate 110 may be formed into a concavo-convex structure, and the one surface may be formed into a flat structure. In some cases, the one surface and the other surface of the semiconductor substrate 110 may be formed into a flat structure.

[0165] The semiconductor substrate 110 may be formed of a P-type or N-type wafer, the first semiconductor layer 120 may be doped with a dopant having a different polarity from that of the semiconductor substrate 110, and the second semiconductor layer 130 may be doped with a dopant having the same polarity as that of the semiconductor substrate 110. For example, the semiconductor substrate 110 may be made of a P-type wafer, the first semiconductor layer 120 may be doped with an N-type dopant, and the second semiconductor layer 130 may be doped with a P-type dopant to form a P+ layer.

[0166] Although not shown, an I-type semiconductor layer may be additionally formed between the semiconductor substrate 110 and the first semiconductor layer 120 and between the semiconductor substrate 110 and the second semiconductor layer 130 .

[0167] Then, if Fig.14bAs shown, a buffer layer 200 is formed on the crystalline solar cell 100 .

[0168] The buffer layer 200 is formed on the first semiconductor layer 120. Since the first semiconductor layer 120 is formed in a concavo-convex structure, the buffer layer 200 is formed in a shape corresponding to the concavo-convex structure.

[0169] The buffer layer 200 is disposed between the crystalline solar cell 100 and a perovskite solar cell 300 described below, and thus the solar cell according to the embodiment of the present invention has a structure of a tandem solar cell based on a tunnel junction.

[0170] It is preferable that the buffer layer 200 contains a material for enabling light having a long wavelength to pass through the perovskite solar cell 300 without loss to be incident on the crystalline solar cell 100. For example, the buffer layer 200 may be formed of a transparent conductive oxide, a carbonaceous conductive material, a metallic material, or a conductive polymer, and in some cases, may be doped with an n-type or p-type dopant with the material.

[0171] Then, if Fig.14c As shown, a perovskite solar cell 300 is formed on the buffer layer 200. Since the buffer layer 200 is formed in a concavo-convex structure, the perovskite solar cell 300 may also be formed in a concavo-convex structure.

[0172] The perovskite solar cell 300 may include a first conductive charge transfer layer disposed on the buffer layer 200 , a light absorbing layer disposed on the first conductive charge transfer layer, and a second conductive charge transfer layer disposed on the light absorbing layer.

[0173] The first conductive charge transfer layer may be formed of an electron transfer layer, and the second conductive charge transfer layer may be formed of a hole transfer layer. Alternatively, the first conductive charge transfer layer may be formed of a hole transfer layer, and the second conductive charge transfer layer may be formed of an electron transfer layer.

[0174] The electron transfer layer may include N-type organic materials such as bathocuproine (BCP), C60 or phenyl-C6l-butyric acid methyl ester (PCBM), various N-type metal oxides such as ZnO, c-TiO2 / mp-TiO2, SnO2 or IZO known to those skilled in the art, and compounds including various N-type organic or inorganic materials.

[0175] The hole transfer layer may contain 2,2′,7,7′-tetrakis[N,N-di(4-methoxyphenyl)amino]-9,9′-spirobifluorene (Spiro-MeO-TAD), 2,2′,7,7′-tetrakis(N,N-di-p-tolyl)amino-9,9-spirobifluorene (Spiro-TTB), polyaniline, polyphenol, poly(3,4-ethylenedioxythiophene)-poly(styrene sulfonate) and the like. sulfonate, PEDOT-PSS), various p-type organic materials such as poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine] (poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine], PTAA, and poly(3-hexylthiophene-2,5-diyl), P3HT; various P-type metal oxides such as Ni oxide, Mo oxide, V oxide, W oxide or Cu oxide known to those skilled in the art; and compounds containing various P-type organic or inorganic materials.

[0176] The light absorbing layer includes the aforementioned perovskite compound thin film, and thus repeated description of the light absorbing layer will be omitted.

[0177] Then, if Fig.14d As shown, a first electrode 400 is formed on the top surface of the perovskite solar cell 300 , and a second electrode 500 is formed on the bottom surface of the crystalline solar cell 100 .

[0178] Since the first electrode 400 is formed on the incident surface for incident sunlight, the first electrode 400 is patterned into a predetermined shape. The second electrode 500 may also be configured to allow reflected light of sunlight to enter the solar cell by forming a pattern of a predetermined shape, but is not limited thereto.

[0179] Then, if Fig.14e As shown, a passivation layer 600 is formed on the first electrode 400. In this case, a portion of the passivation layer 600 is etched to expose the first electrode 400.

[0180] Since the perovskite solar cell 300 is formed into a concavo-convex structure, the passivation layer 600 may also be formed into a concavo-convex structure. The passivation layer 600 may be formed of various materials such as SiO, SiON, SiN, Al2O3, or MgF. In particular, the passivation layer 600 may be made of polydimethylsiloxane, and when polydimethylsiloxane is formed on the perovskite solar cell 300, a concavo-convex structure of a micro-pyramid may be obtained.

[0181] Above, the embodiments of the present invention have been described in more detail with reference to the accompanying drawings, but the present invention is not limited to these embodiments and can be modified in various ways without departing from the technical spirit of the present invention. Therefore, it should be understood that the above embodiments are only exemplary and non-restrictive in all aspects. It should be explained that the scope of the present invention is defined by the following claims rather than by the embodiments, and the scope and meaning of the claims and all changes and modifications derived from the concepts equivalent to the claims are included in the scope of the present invention.

Claims

1. A method for forming a perovskite compound film, comprising: A step of supplying a B precursor into the chamber; A step of supplying an X precursor into the chamber for the first time; as well as The step of supplying the A precursor into the chamber, wherein the B precursor comprises an organic metal compound containing a divalent positive ion, the X precursor comprises a hydrogen halide, and the A precursor comprises at least one compound selected from the group consisting of amine compounds and amidine compounds, and The process of supplying the A precursor is performed after the process of supplying the B precursor and the process of supplying the X precursor for the first time.

2. The method for forming a perovskite compound thin film according to claim 1, wherein: The step of supplying the B precursor includes the step of adsorbing the B precursor on a substrate, and The first step of supplying the X precursor includes forming a BX precursor on the substrate by reacting the B precursor with the X precursor. n (n<3) intermediate materials composed of compounds, The process of supplying the A precursor comprises: n The intermediate material composed of (n<3) compounds reacts with the A precursor to form ABX on the substrate n (n<3) compounds, and Wherein, A comprises at least one monovalent organic positive ion selected from the group consisting of the monovalent organic positive ions of the amine compounds and the monovalent organic positive ions of the amidine compounds, B comprises a divalent positive ion, and X comprises a halogen compound.

3. The method for forming a perovskite compound thin film according to claim 1, further comprising a blowing process performed in at least one of a period between the process of supplying the B precursor and the process of supplying the X precursor for the first time, a period between the process of supplying the X precursor for the first time and the process of supplying the A precursor, and a period after the process of supplying the A precursor. 4 . The method for forming a perovskite compound thin film according to claim 1 , further comprising a step of supplying the X precursor into the chamber for a second time after the step of supplying the A precursor.

5. The method for forming a perovskite compound thin film according to claim 4, wherein: The process of supplying the X precursor into the chamber for the second time includes a process of applying power to form plasma.

6. The method for forming a perovskite compound thin film according to claim 4, further comprising a blowing process performed in at least one of a period between the process of supplying the B precursor and the process of supplying the X precursor for the first time, a period between the process of supplying the X precursor for the first time and the process of supplying the A precursor, a period between the process of supplying the A precursor and the process of supplying the X precursor for the second time, and a period after the process of supplying the X precursor for the second time.

7. The method for forming a perovskite compound thin film according to claim 4, wherein: The step of supplying the B precursor includes the step of adsorbing the B precursor on a substrate, and The first step of supplying the X precursor includes forming a BX precursor on the substrate by reacting the B precursor with the X precursor. n (n<3) primary intermediate materials composed of compounds, The process of supplying the A precursor comprises: n The primary intermediate material composed of (n<3) compounds reacts with the A precursor to form ABX on the substrate. n (n<3) The process of secondary intermediate materials composed of compounds, The second step of supplying the X precursor comprises: n The step of reacting the secondary intermediate material composed of (n<3) compounds with the X precursor to form an ABX3 compound on the substrate, and Wherein, A comprises at least one monovalent organic positive ion selected from the group consisting of the monovalent organic positive ions of the amine compounds and the monovalent organic positive ions of the amidine compounds, B comprises a divalent positive ion, and X comprises a halogen compound.

8. The method for forming a perovskite compound thin film according to claim 1, further comprising the step of supplying a C precursor into the chamber in the step of supplying the B precursor, in, The C precursor comprises at least one alkali metal compound.

9. The method for forming a perovskite compound thin film according to claim 8, wherein: The step of supplying the B precursor and the C precursor includes the step of adsorbing the B precursor and the C precursor on a substrate, and The first step of supplying the X precursor includes forming a CBX on the substrate by reacting the B precursor and the C precursor with the X precursor. n (n<3) intermediate materials composed of compounds, The process of supplying the A precursor comprises: n The intermediate material composed of (n<3) compounds reacts with the A precursor to form CABX on the substrate n (n<3) compounds, and Wherein, A comprises at least one monovalent organic cation selected from the group consisting of the monovalent organic cation of the amine compound and the monovalent organic cation of the amidine compound, B comprises a divalent cation, C comprises an alkali metal, and X comprises a halogen compound.

10. The method for forming a perovskite compound thin film according to claim 1, further comprising a step of supplying a crystal control material into the chamber between the step of supplying the X precursor for the first time and the step of supplying the A precursor.

11. The method for forming a perovskite compound thin film according to claim 10, wherein: The crystal control material comprises pyridine or a pyridine derivative.

12. The method for forming a perovskite compound thin film according to claim 1, wherein: The process of supplying the X precursor into the chamber for the first time includes a process of applying power to form plasma.

13. A method for forming a perovskite compound film, comprising: A step of supplying a B precursor and a C precursor into a chamber; as well as a step of supplying an X precursor into the chamber for the first time, The B precursor comprises an organic metal compound containing a divalent positive ion, the C precursor comprises at least one alkali metal compound, and the X precursor comprises a hydrogen halide. The process of supplying the X precursor for the first time is performed after the process of supplying the B precursor and the C precursor.

14. A method for forming a perovskite compound film, comprising: The step of supplying a C precursor into the chamber; The step of supplying a B precursor into the chamber; as well as a step of supplying an X precursor into the chamber for the first time, The B precursor comprises an organic metal compound containing a divalent positive ion, the C precursor comprises at least one alkali metal compound, and the X precursor comprises a hydrogen halide. The step of supplying the C precursor is performed before the step of supplying the B precursor and the step of supplying the X precursor for the first time.

15. A method for manufacturing a solar cell, comprising: forming crystalline solar cells; forming a buffer layer on the crystalline solar cell; forming a perovskite solar cell on the buffer layer; as well as forming a first electrode on the perovskite solar cell and forming a second electrode on the crystalline solar cell, Wherein, forming the perovskite solar cell comprises the method for forming a perovskite compound thin film as described in claim 1.

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