Thin film deposition equipment, preparation method of perovskite thin film and preparation method of battery

Abstract

The invention relates to the technical field of perovskite batteries, and discloses thin film deposition equipment, a preparation method of a perovskite thin film and a preparation method of a battery. The thin film deposition equipment comprises a cavity and a first heat exchange assembly and / or a second heat exchange assembly, and the cavity is hollow and contains a to-be-deposited material; the first heat exchange assembly comprises a plurality of first heat exchange structures arranged on the side wall face of the cavity in a surrounding mode, a first temperature gradient is formed in the height direction of the cavity, and a longitudinally-changing first temperature field is formed in the cavity. The second heat exchange assembly comprises a plurality of annular second heat exchange structures which are horizontally arranged on the top face of the cavity in a nested mode. A second temperature gradient is formed in the outward direction of the annular center, and a transversely-changing second temperature field is formed in the cavity. The first heat exchange assembly and the second heat exchange assembly transmit energy to the dispersed to-be-deposited material in the cavity in a radiation mode, the gas phase material obtains the temperature field gradient and the moving or diffusing energy gradient in the whole cavity, and precise regulation and control of the deposition rate and direction are achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of perovskite batteries, and in particular to a thin film deposition device, a method for preparing a perovskite thin film, and a method for preparing a battery. Background Art

[0002] At present, solar cells are a major structure for utilizing and developing solar energy. Their working principle is to convert solar energy into electrical energy using the photovoltaic effect. Among them, the perovskite solar cells in the third generation of solar cells have the advantages of simple preparation process and low production cost. The perovskite material as the light absorption layer has the advantages of high carrier mobility, high absorption coefficient, long carrier diffusion length and adjustable band gap. Therefore, perovskite solar cells and related materials have become a research hotspot in the photovoltaic field, and their application prospects are very broad.

[0003] Although perovskite single-junction cells and perovskite-silicon tandem solar cells have broad prospects, they still have a long way to go towards industrialization. Among them, the preparation of perovskite films has become a key factor. However, since the organic compound components of the perovskite film are diffusely deposited during the vacuum thermal evaporation process, it is very difficult to control the deposition direction, deposition rate and deposition uniformity during the deposition process, resulting in the inability to effectively deposit the organic compound layer, reducing the yield and production efficiency, and affecting its industrialization process. Summary of the invention

[0004] In view of this, the present invention provides a thin film deposition device, a method for preparing a perovskite thin film, and a method for preparing a battery to solve the problems of difficult control of perovskite thin film deposition, low yield rate and low production efficiency.

[0005] In the first aspect, the present invention provides a thin film deposition device, comprising: a cavity and a first heat exchange component and / or a second heat exchange component arranged on the cavity, the interior of the cavity is hollow and suitable for accommodating materials to be deposited; the first heat exchange component comprises a plurality of first heat exchange structures arranged around the side wall of the cavity; the plurality of first heat exchange structures are used to form a first temperature gradient along the height direction of the cavity, so as to form a first temperature field that changes longitudinally in the cavity; the second heat exchange component comprises a plurality of second heat exchange structures that are horizontally arranged on the top surface of the cavity; the plurality of second heat exchange structures are annular and nested, and are used to form a second temperature gradient in the direction from the center of the annular ring to the outside, so as to form a second temperature field that changes laterally in the cavity.

[0006] In the present invention, the first heat exchange component radiates temperature inward from the four walls of the cavity, forming a first temperature gradient with longitudinal layered distribution in the cavity, and then forming a first temperature field with longitudinal variation; the second heat exchange component radiates temperature downward from the top of the cavity, forming a second temperature gradient with annular transverse distribution in the cavity, and then forming a second temperature field with annular transverse variation; the first heat exchange component and the second heat exchange component are arranged at the same time, forming a secondary radiation field in the cavity space, and forming temperature gradient changes in different annular areas in the horizontal direction and at different heights in the vertical direction. The first heat exchange component and the second heat exchange component transfer energy to the material to be deposited dispersed in the cavity by radiation. After the gas phase material is radiated by the temperature field of the cavity, it obtains its own temperature field gradient in the entire cavity, thereby realizing the movement of the gas phase material or the diffusion energy gradient, and finally realizing the precise regulation of the deposition rate and deposition direction, and effectively reducing the internal defects of the thin film structure.

[0007] In an optional embodiment, the first heat exchange structure is configured as a heating element and / or a cooling element, and the first heat exchange component includes a heating element and / or a cooling element; the second heat exchange structure is configured as a heating element and / or a cooling element, and the second heat exchange component includes a heating element and / or a cooling element.

[0008] In the present invention, temperature control is achieved by adding a specific circulating agent inside the first heat exchange structure and the second heat exchange structure. The first heat exchange structure and the second heat exchange structure can be set to heating or cooling according to specific control requirements. The temperature gradient provides energy for heat conduction, the heating element provides heating energy, and the cooling element provides cooling energy. The heating energy intensifies the diffusion of the gas-phase material in the cavity, and the cooling energy hinders the diffusion of the gas-phase material in the cavity, thereby accurately controlling the efficiency and uniformity of thin film deposition.

[0009] In an optional embodiment, the temperature range of the heat exchange structure is -50°C to +50°C; the temperature range of the second heat exchange structure is -50°C to +50°C.

[0010] In the present invention, the temperature of the circulating agent in the first heat exchange structure and the second heat exchange structure is adjusted between -50°C and +50°C to achieve the formation of the temperature field inside the cavity, thereby ensuring the control of the material deposition direction and deposition efficiency.

[0011] In an optional embodiment, the temperature gradient between any adjacent first heat exchange structures varies in the range of 1°C / cm-30°C / cm; the temperature gradient between any adjacent second heat exchange structures varies in the range of 1°C / cm-30°C / cm.

[0012] In the present invention, the temperature difference between the first temperature field and the second temperature field in the chamber is between 1°C and 30°C every 1 cm, thereby forming a stable temperature gradient required for depositing a thin film, improving the control of the deposition direction and deposition rate, and ultimately improving the quality of thin film deposition.

[0013] In an optional embodiment, it also includes: a carrier plate fixed to the top of the inner wall of the cavity; an evaporation source arranged at the bottom of the inner wall of the cavity and corresponding to the carrier plate; the evaporation source is suitable for placing and heating the material to be deposited so that the material to be deposited moves toward the surface of the carrier plate to form a thin film structure on the surface of the carrier plate.

[0014] In the present invention, through the above-mentioned carrier plate and evaporation source, the material to be deposited is uniformly attached to the lower surface of the substrate, which facilitates the stable formation of a high-quality thin film structure.

[0015] In an optional embodiment, in the height direction of the cavity, the lowest point of the first temperature field formed by the first heat exchange component is flush with the highest point of the evaporation source; in the direction perpendicular to the height of the cavity, the area of ​​the second temperature field formed by the second heat exchange component is greater than or equal to the area of ​​the carrier plate.

[0016] In the present invention, the lowest point of the first temperature field is flush with the highest point of the evaporation source to ensure that the temperature change of the first temperature field will not have a direct impact on the evaporation temperature of the evaporation source, thereby avoiding affecting the evaporation of the material to be deposited; the area of ​​the second temperature field is greater than or equal to the area of ​​the carrier plate, thereby ensuring that the influence range of the second temperature field covers almost all the evaporated materials to be deposited, thereby ensuring that the material is always within the adjustment range of the temperature field during the deposition process, ensuring accurate control of the deposition direction and rate of the material to be deposited, and improving the quality of the deposited film.

[0017] In a second aspect, the present invention further provides a method for preparing a perovskite thin film, which is applied to the above-mentioned thin film deposition device and comprises the following steps:

[0018] Placing the substrate in a cavity of a thin film deposition device, and forming a first temperature field and / or a second temperature field in the cavity;

[0019] preparing an inorganic compound layer on a surface of a substrate;

[0020] An organic compound layer is prepared on the side of the inorganic compound layer facing away from the substrate, and the inorganic compound layer and the organic compound layer constitute a perovskite thin film.

[0021] In the present invention, a first temperature field and a second temperature field in different directions are set inside a deposition chamber, and energy is transferred to the material to be deposited evaporated from an evaporation source by radiation. Inorganic materials and organic materials are deposited more evenly under the action of the temperature field energy. At the same time, under the action of the temperature field energy, precise control of the deposition rate and direction is achieved, which effectively promotes the combination of the organic material layer and the inorganic compound layer, reduces the defects of the polycrystalline perovskite film, effectively inhibits the trap density of non-radiative recombination and perovskite lattice strain, and significantly enhances charge transfer, which helps to ultimately obtain high-efficiency, long-term stable and highly repeatable perovskite solar cells and stacked solar cells.

[0022] In an optional embodiment, after the step of preparing the organic compound layer on the side of the inorganic compound layer facing away from the substrate, the method further includes: annealing the perovskite film.

[0023] In the present invention, the phase transformation of the perovskite film crystal is achieved by heating, thereby improving the crystallization quality and stability of the perovskite film.

[0024] In an optional embodiment, the inorganic compound layer and the organic compound layer are prepared by vacuum thermal evaporation, and the evaporation rate of the thermal evaporation method is The thickness of the inorganic compound layer is 1 nm to 1000 nm, and the thickness of the organic compound layer is 1 nm to 1000 nm.

[0025] In the present invention, the evaporation rate is The material evaporation is uniform and stable, which helps to more accurately adjust the deposition direction and rate under the action of the temperature field; through the temperature field control method, two material layers with a thickness range of 1nm-1000nm are formed. The materials in this thickness range are uniform, stable and have good consistency.

[0026] In a third aspect, the present invention also includes a method for preparing a perovskite solar cell, comprising:

[0027] providing a substrate;

[0028] Preparing a first carrier transport structure on one side surface of the substrate;

[0029] On a surface of the first carrier transport structure that is relatively away from the substrate, a perovskite film is prepared, wherein the perovskite film is prepared by the above-mentioned method for preparing a perovskite film;

[0030] forming a second carrier transport structure on a surface of the perovskite film facing away from the substrate;

[0031] An electrode structure is prepared on a surface of the second carrier transport layer that is away from the substrate.

[0032] In the present invention, a perovskite single-junction solar cell is taken as an example. A cell with a perovskite thin film prepared by the temperature field control method of the present invention is compared with a cell with a perovskite thin film prepared by a conventional method in an IV test. The photoelectric conversion efficiency of the cell device prepared by the present invention is increased from 10.17% to 16.52%. That is, the preparation method of the perovskite solar cell adopted by the present invention can accurately control the deposition direction, deposition rate and deposition uniformity of the organic material, effectively promote its combination with the inorganic compound layer, reduce the defects of the polycrystalline perovskite film, effectively inhibit the trap density of non-radiative recombination and perovskite lattice strain, significantly enhance charge transfer, thereby improving the efficiency of the perovskite solar cell, and having a lower cost, it is easy to promote the further commercialization of the perovskite solar cell. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0034] Figure 1 is a schematic diagram of a thin film deposition device according to an embodiment of the present invention;

[0035] Figure 2 is a schematic cross-sectional view of a thin film deposition device according to an embodiment of the present invention;

[0036] Figure 3 is a flowchart of preparing a perovskite film according to an embodiment of the present invention;

[0037] Figure 4 is a flowchart of preparing a perovskite solar cell according to an embodiment of the present invention;

[0038] Figure 5 is a schematic diagram of a perovskite solar cell according to an embodiment of the present invention;

[0039] Figure 6 It is a comparison of the power generation efficiency of the perovskite solar cell of the embodiment of the present invention and the power generation efficiency of the conventional perovskite solar cell.

[0040] Description of reference numerals:

[0041] 10. cavity; 20. first heat exchange structure; 30. second heat exchange structure; 40. carrier plate; 50. evaporation source;

[0042] 1. Substrate; 2. First carrier transport structure; 3. Inorganic compound layer; 4. Organic compound layer; 5. Second carrier transport structure; 61. First electrode; 62. Second electrode. DETAILED DESCRIPTION

[0043] The present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It is understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention. It should also be noted that, for ease of description, only some structures related to the present invention are shown in the accompanying drawings, rather than all structures. In the following description, the description of known structures and technologies is omitted to avoid unnecessary confusion of the concept of the present invention. Various structural schematic diagrams according to embodiments of the present invention are shown in the accompanying drawings. These figures are not drawn to scale, and some details are magnified for the purpose of clear expression, and some details may be omitted. The shapes of various regions and layers shown in the figures and the relative sizes and positional relationships between them are only exemplary, and may be deviated due to manufacturing tolerances or technical limitations in practice, and those skilled in the art may additionally design regions / layers with different shapes, sizes, and relative positions according to actual needs. In the context of the present invention, when a layer / element is referred to as being "on" another layer / element, the layer / element may be directly on the other layer / element, or there may be an intermediate layer / element between them. In addition, if one layer / element is "on" another layer / element in one orientation, then when the orientation is reversed, the layer / element may be "below" the other layer / element.

[0044] like Figure 1 and Figure 2 As shown, this embodiment provides a thin film deposition device, including: a cavity 10 and a first heat exchange component and a second heat exchange component arranged on the cavity 10, wherein the interior of the cavity 10 is hollow and suitable for accommodating the material to be deposited; the first heat exchange component includes a plurality of first heat exchange structures 20 arranged around the side wall of the cavity 10, and the plurality of first heat exchange structures 20 are used to form a first temperature gradient along the height direction of the cavity 10, so as to form a first temperature field that changes longitudinally in the cavity 10; the second heat exchange component includes a plurality of second heat exchange structures 30 horizontally arranged on the top surface of the cavity 10, and the plurality of second heat exchange structures 30 are annular and nested, and are used to form a second temperature gradient in the direction from the center of the annular shape to the outside, so as to form a second temperature field that changes laterally in the cavity 10.

[0045] Specifically, the above-mentioned cavity 10 is set as a vacuum cavity; the multiple annular first heat exchange structures 20 of the first heat exchange component are uniformly spaced around the outer wall of the cavity 10 in the vertical direction, each annular first heat exchange structure 20 has the same diameter, and is horizontally arranged on the cavity 10 to form a first temperature gradient in the longitudinal direction of the four walls of the cavity 10; the multiple annular second heat exchange structures 30 of the second heat exchange component are concentrically nested and arranged on the outer surface of the top of the cavity 10 in the horizontal direction, the center of the annular ring is the center point of the upper top surface, and the radius of each annular second heat exchange structure 30 from the center of the annular ring to the outside gradually increases, forming a second temperature gradient in the transverse direction of the top of the cavity 10. The first heat exchange component and the second heat exchange component transfer energy to the material to be deposited dispersed in the cavity 10 by radiation. After the gas phase material is radiated by the temperature field of the cavity 10, it obtains its own temperature field gradient in the entire cavity 10, thereby realizing the movement of the gas phase material or the diffusion energy gradient, and finally realizing the precise control of the deposition rate and deposition direction.

[0046] Of course, the thin film deposition equipment of this embodiment can only be provided with the first heat exchange component, and the temperature is radiated inward from the four walls of the cavity 10 to form a first temperature gradient with longitudinal layered distribution in the cavity 10, thereby forming a first temperature field with longitudinal variation; or only the second heat exchange component can be provided, and the temperature is radiated downward from the top of the cavity 10 to form a second temperature gradient with annular transverse distribution in the cavity 10, thereby forming a second temperature field with annular transverse variation. Both methods set a primary radiation field in the space inside the cavity 10 to control the deposition direction and deposition rate. In this embodiment, it is preferred to set the first heat exchange component and the second heat exchange component at the same time, set a secondary radiation field in the space inside the cavity 10, and form temperature gradient changes in different annular areas in the horizontal direction and at different heights in the vertical direction, so as to more accurately control the deposition direction and deposition rate.

[0047] In one embodiment, the first heat exchange structure 20 is configured as a heating element and / or a cooling element, and the first heat exchange component includes multiple heating elements and / or multiple cooling elements; the second heat exchange structure 30 is configured as a heating element and / or a cooling element, and the second heat exchange component includes multiple heating elements and / or multiple cooling elements.

[0048] Specifically, the above-mentioned heating element and cooling element are realized by adding a specific circulating agent inside thereof, the temperature of the circulating agent is changed by an external refrigeration or heating machine, and then circulated in the heating element or cooling element by a circulating pump. When the temperature of the circulating agent introduced is greater than the set temperature of the carrier 40 for thin film deposition, the heat exchange structure is defined as a heating element, and when the temperature of the circulating agent introduced is less than or equal to the set temperature of the carrier 40 for thin film deposition, the heat exchange structure is defined as a cooling element. The first heat exchange structure 20 and the second heat exchange structure 30 can be set to heating or cooling according to specific control requirements. The temperature gradient provides energy for heat conduction, the heating element provides heating energy, and the cooling element provides cooling energy. The heating energy intensifies the diffusion of the gas phase material in the cavity 10, and the cooling energy hinders the diffusion of the gas phase material in the cavity 10. Taking the first heat exchange component as an example, when the temperature of the multiple first heat exchange structures 20 gradually increases from top to bottom, the first temperature gradient increases from top to bottom. Since evaporation is carried out from bottom to top, the evaporation rate of the material to be deposited will be accelerated and the deposition direction will be further limited to bottom to top, thereby improving the deposition efficiency and uniformity.

[0049] In one embodiment, the temperature range of the first heat exchange structure 20 is -50°C to +50°C; the temperature range of the second heat exchange structure 30 is -50°C to +50°C. Exemplarily, the temperature of the circulating agent in the first heat exchange structure 20 and the second heat exchange structure 30 is adjusted between -50°C and +50°C to achieve the formation of the temperature field inside the cavity 10, ensuring the control of the material deposition direction and deposition efficiency. The heating or cooling method of the four walls of the cavity 10 has the temperature adjustability in the vertical direction, and can form a first temperature gradient change at different heights from the heating source in the vertical direction; the heating or cooling method of the chamber top has the temperature adjustability in the horizontal direction, and can form a second temperature gradient change in different annular areas in the horizontal direction.

[0050] In one embodiment, the temperature gradient between any adjacent first heat exchange structures 20 varies in the range of 1°C / cm-30°C / cm; the temperature gradient between any adjacent second heat exchange structures 30 varies in the range of 1°C / cm-30°C / cm. In other words, the temperature difference between the first temperature field and the second temperature field in the chamber is between 1°C-30°C per 1 cm, thereby forming a stable temperature gradient required for depositing thin films, improving the control of deposition direction and deposition rate, and ultimately improving the quality of thin film deposition.

[0051] On the basis of the above scheme, Figure 2 As shown, the thin film deposition equipment also includes: a carrier 40 and an evaporation source 50, the carrier 40 is fixed to the top of the inner wall of the cavity 10; the evaporation source 50 is arranged at the bottom of the inner wall of the cavity 10 and corresponds to the carrier 40; the evaporation source 50 is suitable for placing and heating the material to be deposited so that the material to be deposited moves toward the surface of the carrier 40 to form a thin film structure on the surface of the carrier 40.

[0052] Specifically, a carrier plate 40 is arranged on the top surface inside the cavity 10, and the carrier plate 40 is used to fix the substrate 1 for thin film deposition. As a preferred method, the carrier plate 40 is arranged as a rotatable structure to drive the substrate 1 to rotate evenly when depositing materials; an evaporation source 50 with a heating function is arranged at the bottom of the cavity 10, and is preferably arranged coaxially with the upper carrier plate 40, and the evaporation source 50 has a groove for placing the material to be deposited. As the temperature of the evaporation source 50 rises, the material to be deposited in the evaporation source 50 gradually evaporates upward, and the carrier plate 40 drives the substrate 1 to rotate evenly, and the material to be deposited below gradually and evenly adheres to the lower surface of the substrate 1 to form a thin film structure; through the above-mentioned carrier plate 40 and evaporation source 50, the material to be deposited is evenly and consistently adhered to the lower surface of the substrate 1 to form a high-quality thin film structure.

[0053] Specifically, the thin film structure in this embodiment is a perovskite thin film, which includes two steps of inorganic component deposition and organic component deposition. The step-by-step evaporation method is adopted to first evaporate a layer of perovskite precursor inorganic compound or inorganic halide by changing the temperature gradient and temperature field in the vacuum cavity 10, and then evaporate a layer of perovskite precursor organic compound or organic halide on the inorganic compound, and finally heat to form the perovskite film.

[0054] In one embodiment, in the height direction of the cavity 10, the lowest point of the first temperature field formed by the first heat exchange component is flush with the highest point of the evaporation source 50 to ensure that the temperature change of the first temperature field will not have a direct impact on the evaporation temperature of the evaporation source 50, thereby avoiding affecting the evaporation of the material to be deposited; in the direction perpendicular to the height of the cavity 10, the area of ​​the second temperature field formed by the second heat exchange component is greater than or equal to the area of ​​the carrier 40. Usually, the area of ​​the carrier 40 is larger than the area of ​​the evaporation source 50. Therefore, setting the area of ​​the second temperature field larger than the area of ​​the carrier 40 can ensure that the influence range of the second temperature field covers almost all the evaporated materials to be deposited, thereby ensuring that the material is always within the adjustment range of the temperature field during the deposition process, ensuring precise control of the deposition direction and rate of the material to be deposited, and improving the quality of the deposited film.

[0055] like Figure 3 As shown, this embodiment also provides a method for preparing a perovskite film, which is applied to the above-mentioned thin film deposition device and includes the following steps:

[0056] S101 , placing a substrate 1 in a chamber 10 of a thin film deposition device, and forming a first temperature field and / or a second temperature field in the chamber 10 .

[0057] The substrate 1 is arranged above the cavity 10, and the cavity 10 has a first temperature field with a longitudinal gradient on the four walls of the cavity 10 and a second temperature field with a circular lateral gradient on the top of the cavity 10; or the first temperature field and the second temperature field can also act separately, and the deposition direction and rate of the thin film deposition are controlled by the temperature change of the temperature field.

[0058] S102 , preparing an inorganic compound layer 3 on the surface of the substrate 1 .

[0059] The inorganic material for preparing the inorganic compound layer 3 is one or more of lead iodide (PbI2), lead bromide (PbBr2), lead chloride (PbCl2), cesium iodide (CsI), cesium bromide (CsBr), and cesium chloride (CsCl).

[0060] S103, preparing an organic compound layer 4 on the side of the inorganic compound layer 3 facing away from the substrate 1, the inorganic compound layer 3 and the organic compound layer 4 constitute a perovskite thin film.

[0061] The organic material for preparing the organic compound layer 4 is one or more of methylammonium iodide (MAI), methylammonium bromide (MABr), methylammonium chloride (MACl), formamidine hydroiodide (FAI), formamidine hydrobromide (FABr), and formamidine hydrochloride (FACl).

[0062] By setting the first temperature field and the second temperature field in different directions in the deposition chamber 10, energy is transferred to the to-be-deposited material evaporated from the evaporation source 50, including inorganic materials and organic materials, by radiation, so that the material can be deposited more evenly under the action of the temperature field energy. At the same time, under the action of the temperature field energy, the deposition rate and direction are precisely controlled to solve the problems of deposition direction, deposition rate and deposition uniformity of the to-be-deposited material, especially the organic compound layer 4, during vacuum thermal evaporation, effectively promote the combination of the organic material layer and the inorganic compound layer 3, reduce the defects of the polycrystalline perovskite film, effectively suppress the trap density of non-radiative recombination and perovskite lattice strain, significantly enhance charge transfer, and ultimately help to obtain high-efficiency, long-term stable and highly repeatable perovskite solar cells and stacked solar cells.

[0063] In one embodiment, after the step of preparing the organic compound layer 4 on the side of the inorganic compound layer 3 facing away from the substrate 1, the method further comprises:

[0064] S104, annealing the perovskite film to achieve phase transformation of the perovskite film crystals by heating annealing, thereby improving the crystallization quality and stability of the perovskite film.

[0065] In one embodiment, the inorganic compound layer 3 and the organic compound layer 4 are prepared by vacuum thermal evaporation, and the evaporation rate of the thermal evaporation method is At this evaporation rate, the material evaporates evenly and stably, and it helps to adjust the deposition direction and rate more accurately under the action of the temperature field; the thickness of the inorganic compound layer 3 is 1nm-1000nm, and the thickness of the organic compound layer 4 is 1nm-1000nm. The two material layers in the above thickness range are formed by the above-mentioned temperature field control method, and the materials in this thickness range are uniform, stable and consistent.

[0066] like Figure 4 As shown, this embodiment also provides a method for preparing a perovskite solar cell. The structure of the prepared perovskite solar cell is as shown in Figure 5 As shown, the preparation method comprises the following steps:

[0067] S201, providing a substrate 1.

[0068] Exemplarily, the substrate 1 can be set as a transparent substrate such as ITO conductive glass, FTO conductive glass, etc. Before depositing the material on the ground, the substrate is first ultrasonically cleaned for 15 minutes with glass cleaning agent, deionized water, acetone, isopropanol, ethanol, etc. in sequence, and the surface of the substrate 1 is cleaned according to the cleaning ability of different reagents; then the substrate 1 is blown dry with dry air, and finally UV-ozone treatment is performed for 20 minutes to obtain a dry and clean substrate 1.

[0069] S202 , preparing a first carrier transport structure 2 on one side surface of the substrate 1 .

[0070] For example, the first carrier transport structure 2 is a hole transport structure, which is configured as nickel oxide (NiO x )+phosphonic acid (Meo-2pacz) double hole transport layer structure. Among them, NiO x At a concentration of 20 mg / ml, ultrasonically vibrate in deionized water for 30 minutes and filter before use. Then, at a concentration of 1 mg / ml, ultrasonically vibrate Meo-2pacz in deionized water for 30 minutes and filter before use. x The deposition parameters of the hole transport layer are set as: carrier 40 speed 3000 rpm, deposition time 30 s and annealing at 200°C for 20 min; the deposition parameters of the Meo-2pacz hole transport layer are set as: carrier 40 speed 3000 rpm, deposition time 30 s and annealing at 200°C for 10 min.

[0071] S203, preparing a perovskite film on a surface of the first carrier transport structure 2 opposite to the substrate 1, wherein the perovskite film is prepared by the above-mentioned method for preparing a perovskite film.

[0072] Specifically, the steps include:

[0073] S2031, preparing the inorganic compound layer 3 by evaporation method, placing PbI2, PbBr2, and CsI in the evaporation source 50 of the evaporation chamber 10 for three-source co-evaporation, and the thickness of the deposited inorganic compound layer 3 is 250 nm.

[0074] S2032, preparing the organic compound layer 4 by evaporation method, putting FAI into the evaporation source 50 of the evaporation chamber 10 for evaporation, and depositing the organic compound layer 4 to a thickness of 250 nm.

[0075] S2033, annealing at 150°C for 30 min in air with relative humidity Rh=30%.

[0076] In the above steps S2031 to S2033, the deposition direction and deposition efficiency of the perovskite thin film deposition process are controlled by adding temperature field control, and a uniform perovskite thin film layer is obtained by evaporation.

[0077] S204 , forming a second carrier transport structure 5 on a surface of the perovskite film that is away from the substrate 1 .

[0078] Exemplarily, the second carrier transport structure 5 is an electron transport structure, which in this embodiment is set to a double electron transport layer structure of C60 electron transport layer + BCP (2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline) electron transport layer; the C60 electron transport layer is deposited at about 20nm and the BCP electron transport layer is deposited at about 8nm.

[0079] S205 , preparing an electrode structure on a surface of the second carrier transport layer that is away from the substrate 1 .

[0080] Exemplarily, the electrode structure is a metal electrode, including a first electrode 61 and a second electrode 62 serving as positive and negative electrodes respectively. Specifically, the electrode structure is a metal silver electrode with a thickness of 120 nm in this embodiment.

[0081] The perovskite solar cell of this embodiment may be a perovskite single-junction solar cell including a perovskite thin film prepared by the above-mentioned thin film deposition equipment, or may be a full perovskite stacked solar cell or a crystalline silicon-perovskite stacked solar cell.

[0082] Taking a perovskite single junction solar cell as an example, a cell having a perovskite film prepared by the temperature field control method of this embodiment is compared with a cell having a perovskite film prepared by a conventional method by IV testing. Figure 6As shown, curve a is the test curve corresponding to the solar cell of this embodiment, and curve b is the test curve corresponding to the conventional solar cell. It can be obtained that the photoelectric conversion efficiency of the battery device prepared in this embodiment is increased from 10.17% to 16.52%. Therefore, the preparation method of the perovskite solar cell of this embodiment can accurately control the deposition direction, deposition rate and deposition uniformity of the organic material, effectively promote its combination with the inorganic compound layer 3, reduce the defects of the polycrystalline perovskite film, effectively inhibit the trap density of non-radiative recombination and perovskite lattice strain, significantly enhance charge transfer, thereby improving the efficiency of the perovskite solar cell, and has a low cost, which is easy to promote the further commercialization of perovskite solar cells.

[0083] In the above description, the technical details of the patterning and etching of each layer are not described in detail. However, those skilled in the art should understand that various technical means can be used to form layers, regions, etc. of desired shapes. In addition, in order to form the same structure, those skilled in the art can also design methods that are not completely the same as the methods described above. In addition, although the various embodiments are described above separately, this does not mean that the measures in the various embodiments cannot be used in combination to advantage.

[0084] Although the embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art may make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations are all within the scope defined by the appended claims.

Claims

1. A thin film deposition device, characterized in that: include: A cavity (10), wherein the cavity (10) is hollow inside and is suitable for accommodating a material to be deposited; and arranged on the cavity (10): A first heat exchange component, comprising a plurality of first heat exchange structures (20) arranged around the side wall of the cavity (10); the plurality of first heat exchange structures (20) are used to form a first temperature gradient in a height direction along the cavity (10), so as to form a first temperature field that varies longitudinally in the cavity (10); and / or a second heat exchange component, comprising a plurality of second heat exchange structures (30) horizontally arranged on the top surface of the cavity (10); the plurality of second heat exchange structures (30) are annular and nested, and are used to form a second temperature gradient in a direction outward from the center of the annular shape, so as to form a second temperature field that changes laterally in the cavity (10).

2. The thin film deposition device according to claim 1, characterized in that: The first heat exchange structure (20) is configured as a heating element and / or a cooling element, and the first heat exchange component comprises a heating element and / or a cooling element; The second heat exchange structure (30) is configured as a heating element and / or a cooling element, and the second heat exchange component comprises a heating element and / or a cooling element.

3. The thin film deposition device according to claim 2, characterized in that: The temperature range of the heat exchange structure is -50°C to +50°C; the temperature range of the second heat exchange structure (30) is -50°C to +50°C.

4. The thin film deposition device according to claim 3, characterized in that: The temperature gradient between any adjacent first heat exchange structures (20) varies in the range of 1°C / cm-30°C / cm; the temperature gradient between any adjacent second heat exchange structures (30) varies in the range of 1°C / cm-30°C / cm.

5. The thin film deposition device according to any one of claims 1 to 4, characterized in that: Also includes: A carrier plate (40) fixed to the top of the inner wall of the cavity (10); An evaporation source (50) is arranged at the bottom of the inner wall of the cavity (10) and corresponds to the carrier (40); the evaporation source (50) is suitable for placing and heating the material to be deposited, so that the material to be deposited moves toward the surface of the carrier (40) to form a thin film structure on the surface of the carrier (40).

6. The thin film deposition device according to claim 5, characterized in that: In the height direction of the cavity (10), the lowest point of the first temperature field formed by the first heat exchange component is flush with the highest point of the evaporation source (50); In a direction perpendicular to the height of the cavity (10), the area of ​​the second temperature field formed by the second heat exchange component is greater than or equal to the area of ​​the carrier plate (40).

7. A method for preparing a perovskite thin film, applied to the thin film deposition device according to any one of claims 1 to 6, characterized in that: include: Placing a substrate (1) in a cavity (10) of a thin film deposition device, wherein a first temperature field and / or a second temperature field is formed in the cavity (10); Preparing an inorganic compound layer (3) on the surface of the substrate (1); An organic compound layer (4) is formed on the side of the inorganic compound layer (3) facing away from the substrate (1), and the inorganic compound layer (3) and the organic compound layer (4) constitute a perovskite thin film.

8. The method for preparing a perovskite thin film according to claim 7, characterized in that: After the step of preparing the organic compound layer (4) on the side of the inorganic compound layer (3) facing away from the substrate (1), the method further comprises: The perovskite film is subjected to annealing treatment.

9. The method for preparing a perovskite thin film according to claim 8, characterized in that: The inorganic compound layer (3) and the organic compound layer (4) are prepared by vacuum thermal evaporation, and the evaporation rate of the thermal evaporation method is The thickness of the inorganic compound layer (3) is 1 nm to 1000 nm, and the thickness of the organic compound layer (4) is 1 nm to 1000 nm.

10. A method for preparing a perovskite solar cell, characterized in that: include: Providing a substrate (1); Preparing a first carrier transport structure (2) on one side surface of the substrate (1); A perovskite film is prepared on a surface of the first carrier transport structure (2) which is relatively away from the substrate (1), wherein the perovskite film is prepared by the method for preparing a perovskite film according to any one of claims 7 to 9; forming a second carrier transport structure (5) on a surface of the perovskite film that is away from the substrate (1); An electrode structure is prepared on the surface of the second carrier transport layer on the side facing away from the substrate (1).

Images