A large-area copper-zinc-tin-sulfur-selenium solar cell assembly and its preparation method and application

Abstract

The present invention discloses a large-area copper-zinc-tin-sulfur-selenium solar cell assembly, its preparation method, and application. The assembly comprises, from bottom to top, a soda-lime glass layer, a molybdenum conductive layer, a copper-zinc-tin-sulfur-selenium absorption layer, a cadmium sulfide buffer layer, a high-resistance window layer, and a conductive layer with a low-resistance window layer. The present invention introduces a scribing process into the preparation of copper-zinc-tin-sulfur-selenium solar cells, thereby achieving large-area preparation, modularization, and series integration of copper-zinc-tin-sulfur-selenium solar cells, allowing multiple copper-zinc-tin-sulfur-selenium solar cells connected in series to transmit electricity to the outside world together. By changing the area and number of cells connected in series, the power requirements of different external circuits can be met. The present invention is one of the important cornerstones for the commercialization of copper-zinc-tin-sulfur-selenium solar cells.

Description

Technical Field

[0001] The present invention belongs to the technical field of thin-film solar cells, and in particular relates to a large-area copper-zinc-tin-sulfur-selenium solar cell assembly and a preparation method and application thereof. Background Art

[0002] Solar energy, a clean and renewable energy source, boasts the advantage of being unrestricted by natural and geographical conditions. Effectively utilizing solar cells is a key foundation for my country's strategy to achieve carbon peak by 2030 and carbon neutrality by 2060. Solar cells convert sunlight into electricity, making them an ideal way to utilize solar energy. The earliest solar cells were silicon-based solar cells, developed by Martin Green of the University of New South Wales. This early-mover advantage has enabled silicon-based solar cells to enjoy a significant market share. However, silicon-based solar cells also have significant drawbacks: large material requirements, high purity requirements, complex manufacturing processes, and limited application scenarios. These drawbacks are the primary reason for the high price of silicon-based solar cells. Therefore, developing new, low-cost solar cells is a crucial support and guarantee for achieving China's strategy of gradually replacing fossil fuels. Meanwhile, copper indium gallium selenide (CIGS) solar cells, which are currently commercially produced and have the potential to replace silicon-based solar cells, remain relatively expensive. Furthermore, the gallium element in CIGS solar cells is scarce in the Earth's crust, and further expansion of production will inevitably lead to a significant increase in their market price. Therefore, copper zinc tin sulfur (CZTS) solar cells, which are derived from copper indium gallium selenide solar cells and whose constituent elements are abundant in the earth's crust, have always been the focus of research, and the research enthusiasm is accelerating.

[0003] The band gap of copper-zinc-tin-sulfur solar cells is 1.0 eV. If the sulfur element in CZTS is replaced by selenium (Se), which is also in Group VI, its band gap can be adjusted within the range of 1.0 to 1.5 eV. The optical absorption coefficient of copper-zinc-tin-sulfur-selenium solar cells in the visible light range is >10 4 A thickness of a few microns is enough to fully utilize sunlight. Therefore, the biggest advantage of copper-zinc-tin-sulfur solar cells lies in their wide source of elemental composition, high abundance, and low toxicity, making them an ideal green photovoltaic material.

[0004] Currently, there are two methods for preparing copper-zinc-tin-sulfur (CuZnS) solar cells: the solution method and the vacuum method. The traditional vacuum method requires complex equipment and has high production costs, which is not conducive to leveraging the low manufacturing cost advantage of CuZnS, TinS, and its efficiency has yet to break IBM's world record of 12.6%. The solution method, on the other hand, does not require complex production equipment or a high-vacuum production environment. Thanks to the unique grain growth mechanism of the solution method, through Ag doping, heterojunction heat treatment, and the use of tetravalent tin, the efficiency of CuZnS solar cells has reached 13%, and this efficiency has been certified by the U.S. Renewable Energy Laboratory. The fact that the efficiency of CuZnS solar cells can be gradually improved indicates that they have the potential for commercial application.

[0005] The current research on copper-zinc-tin-sulfur solar cells is mainly based on the effective area less than 1cm 2 These isolated small-area solar cells cannot meet the standards and requirements of commercial solar cells. To solve this problem, we need to increase the area of ​​a single solar cell and develop a reasonable internal structure to connect multiple solar cells in series and transmit power to the outside world. Summary of the Invention

[0006] The purpose of this section is to summarize some aspects of the embodiments of the present invention and briefly introduce some preferred embodiments. Some simplifications or omissions may be made in this section and the abstract and title of this application to avoid obscuring the purpose of this section, the abstract and the title of the invention, and such simplifications or omissions should not be used to limit the scope of the present invention.

[0007] In view of the above problems and / or the problems existing in the prior art, the present invention is proposed.

[0008] Therefore, the purpose of the present invention is to overcome the deficiencies in the prior art and provide a large-area copper-zinc-tin-sulfur-selenium solar cell assembly.

[0009] To solve the above technical problems, the present invention provides the following technical solutions: a large-area copper-zinc-tin-sulfur-selenium solar cell module, characterized in that the cell module is arranged in layers, from bottom to top: a soda-lime glass layer, a molybdenum conductive layer, a copper-zinc-tin-sulfur-selenium absorption layer, a cadmium sulfide buffer layer, a high-resistance window layer, and a low-resistance window layer.

[0010] As a preferred solution of the large-area copper-zinc-tin-sulfur-selenium solar cell assembly described in the present invention, the high-resistance window layer is intrinsic zinc oxide, and the low-resistance window layer is aluminum-doped zinc oxide (AZO) or indium tin oxide (ITO).

[0011] As a preferred solution of the large-area copper-zinc-tin-sulfur-selenium solar cell assembly described in the present invention, the battery assemblies can be connected in series to form a battery pack.

[0012] As a preferred solution of the large-area copper-zinc-tin-sulfur-selenium solar cell assembly of the present invention, each layer of the solar cell assembly contains multiple scratches of varying depths.

[0013] Another object of the present invention is to provide a method for preparing a large-area copper-zinc-tin-sulfur-selenium solar cell assembly.

[0014] In order to solve the above technical problems, the present invention provides the following technical solution: a method for preparing a large-area copper-zinc-tin-sulfur-selenium solar cell module, characterized in that it comprises the following steps:

[0015] (1) Scribing a molybdenum-coated glass substrate to divide the molybdenum conductive layer according to a designed pattern;

[0016] (2) preparing a copper, zinc, tin, sulfur and selenium absorption layer on the molybdenum conductive layer described in step (1);

[0017] (3) preparing a cadmium sulfide buffer layer on the copper-zinc-tin-sulfur-selenium absorption layer described in step (2);

[0018] (4) preparing a window layer of intrinsic zinc oxide on the cadmium sulfide buffer layer described in step (3);

[0019] (5) Scribing the thin film obtained in step (4) by a certain method, scribing according to the designed pattern, and drawing the line to the molybdenum, that is, cutting the intrinsic zinc oxide window layer, the cadmium sulfide buffer layer, and the copper-zinc-tin-sulfur-selenium absorption layer, thereby creating a channel that can be used to connect adjacent copper-zinc-tin-sulfur-selenium solar cells later.

[0020] (6) A window layer of AZO or ITO is prepared on the thin film obtained in step (5), so that the connection channel between the top electrode and the bottom electrode of the adjacent battery is successfully created.

[0021] (7) Scribing the thin film obtained in step (6) according to a certain method to divide the top electrode according to the design. This scribing can remove AZO or ITO according to different methods, or it can be scratched to molybdenum (i.e., removing AZO or ITO; i-ZnO; CdS).

[0022] (8) The thin film prepared in (7) is used to prepare a large-area copper-zinc-tin-sulfur-selenium thin film solar cell module after differentiating the electrodes.

[0023] As a preferred embodiment of the preparation method of the large-area copper-zinc-tin-sulfur-selenium solar cell module described in the present invention, the method comprises the following steps: the copper-zinc-tin-sulfur-selenium absorption layer includes but is not limited to a copper-zinc-tin-sulfur-selenium absorption layer and various absorption layers doped with other elements, a copper-zinc-tin-sulfur absorption layer without selenium and various absorption layers obtained by doping with other elements, a copper-zinc-tin-sulfur absorption layer without sulfur and various absorption layers obtained by doping with other elements.

[0024] As a preferred solution of the method for preparing a large-area copper-zinc-tin-sulfur-selenium solar cell module described in the present invention, scribing includes but is not limited to mechanical scribing, laser scribing, and etching scribing with various etching solutions after protecting specific areas with photoresist.

[0025] As a preferred embodiment of the method for preparing a large-area copper-zinc-tin-sulfur-selenium solar cell module according to the present invention, the order of scribing in steps (1), (5), and (7) includes the situations where the scribing is performed simultaneously or any one of the scribing procedures is performed before, during, or after.

[0026] Another object of the present invention is to provide an application of a large-area copper-zinc-tin-sulfur-selenium solar cell assembly.

[0027] To solve the above technical problems, the present invention provides the following technical solution: an application of a large-area copper-zinc-tin-sulfur-selenium solar cell assembly, which includes: using the prepared large-area copper-zinc-tin-sulfur-selenium thin film battery assembly to prepare a solar cell.

[0028] As a preferred solution for the application of the large-area copper-zinc-tin-sulfur-selenium solar cell assembly of the present invention, the large-area copper-zinc-tin-sulfur-selenium thin-film cells can be connected in series to increase the area of ​​the assembly.

[0029] Beneficial effects of the present invention:

[0030] 1. The present invention prepares large-area solar cells based on copper-zinc-tin-sulfur-selenium materials, and is the first to apply copper-zinc-tin-sulfur-selenium to the preparation of large-area solar cells.

[0031] 2. The present invention is the first to use a solution method to prepare the absorption layer of a large-area copper-zinc-tin-sulfur-selenium solar cell.

[0032] 3. The present invention modularizes solar cells and can obtain high-efficiency copper-zinc-tin-sulfur-selenium solar cells by connecting multiple copper-zinc-tin-sulfur-selenium solar cells in series.

[0033] 4. The present invention is the first to use the method of etching with an etchant after photoresist protection in the scribing of copper-zinc-tin-sulfur-selenium solar cell modules. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. Those skilled in the art can also derive other drawings based on these drawings without inventive effort. Among them:

[0035] Figure 1 Schematic diagram of the finished structure of the copper-zinc-tin-sulfur-selenium solar cell produced by the present invention,

[0036] In the figure, from bottom to top, there are soda-lime glass, molybdenum conductive layer, copper-zinc-tin-sulfur-selenium absorption layer, cadmium sulfide buffer layer, intrinsic zinc oxide window layer, and aluminum-doped zinc oxide;

[0037] Figure 2 Schematic diagram of P1 scratching,

[0038] In the figure, the left side shows P1 before scribing, and the right side shows P1 after scribing;

[0039] Figure 3 This is a schematic diagram of the marking of P2.

[0040] In the figure, the left side shows P2 before marking, and the right side shows P2 after marking;

[0041] Figure 4 This is a schematic diagram of the marking of P3.

[0042] In the figure, the left side shows P3 before marking, and the right side shows P3 after marking;

[0043] Figure 5 This is the overall process flow chart for preparing CZTSSe components;

[0044] Figure 6 Schematic diagram of the overall structure of the CZTSSe module;

[0045] Figure 7 This is a physical picture of the finished product obtained by the first scribing method provided in Example 9 of the present invention;

[0046] Figure 8 This is an IV curve of the finished product obtained by the first scribing method provided in Example 9 of the present invention;

[0047] Figure 9 This is a photo of the finished product obtained by the second scribing method provided in Example 9 of the present invention;

[0048] Figure 10 This is an IV curve of the finished product obtained by the second scribing method provided in Example 9 of the present invention;

[0049] Figure 11 This is a photo of the finished product obtained by the first scribing method provided in Example 9 of the present invention;

[0050] Figure 12 This is an IV curve of the finished product obtained by the first scribing method provided in Example 9 of the present invention;

[0051] Figure 13 This is a SEM image of the finished product obtained by scribing method 1 provided in Example 9 of the present invention;

[0052] Figure 14 This is a SEM image of the finished product obtained by scribing method 2 provided in Example 9 of the present invention;

[0053] Figure 15 This is a SEM image of the finished product obtained by scribing method 3 provided in Example 9 of the present invention;

[0054] Figure 16 A JV curve diagram of a single battery before series connection provided in Example 10 of the present invention;

[0055] Figure 17 This is a flow chart of etching liquid marking provided in Example 10 of the present invention. DETAILED DESCRIPTION

[0056] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the embodiments of the specification.

[0057] In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0058] Secondly, the term "one embodiment" or "embodiment" herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The phrase "in one embodiment" appearing in various places throughout this specification does not necessarily refer to the same embodiment, nor does it refer to a separate or selective embodiment that is mutually exclusive of other embodiments.

[0059] The molybdenum-coated glass used in the present invention is a common commercial product.

[0060] Example 1

[0061] This example is used to illustrate the structure and macroscopic formation mechanism of copper-zinc-tin-sulfur-selenium thin films:

[0062] The molybdenum-plated glass substrate used in this embodiment needs to meet the requirement that the thickness of the molybdenum metal on the glass is between 800 nm and 1000 nm.

[0063] The molybdenum-coated glass substrate is scratched by a certain method, and the molybdenum conductive layer is divided according to the designed pattern. The obtained film is as follows Figure 2 This marking is called P1.

[0064] A copper-zinc-tin-sulfur-selenium absorption layer is prepared on the molybdenum conductive layer;

[0065] A cadmium sulfide buffer layer is prepared on the copper-zinc-tin-sulfur-selenium absorption layer;

[0066] A window layer of intrinsic zinc oxide is prepared on the upper layer of the cadmium sulfide buffer layer;

[0067] The film obtained by the above steps is as follows Figure 3 As shown, a line is scribed on the film using a specific method, following a designed pattern until it reaches the molybdenum layer, thus cutting through the intrinsic zinc oxide window layer, the cadmium sulfide buffer layer, and the copper-zinc-tin-sulfur-selenide absorber layer. This creates a channel that can later connect adjacent copper-zinc-tin-sulfur-selenide solar cells. This scribe is marked P2.

[0068] After P2 is completed, a window layer of AZO or ITO is prepared on the film, so that the top electrode and bottom electrode connection channel of the adjacent cells are successfully created. The film is as follows Figure 4 shown.

[0069] Depend on Figure 4 After the window layer is prepared, the thin film of AZO or ITO is scribed to divide the electrodes according to the design. During this step, the AZO or ITO can be removed, and the line can also be drawn to the molybdenum (i.e., AZO or ITO is removed; i-ZnO; CdS is removed). This scribe is marked as P3.

[0070] Example 2

[0071] This embodiment describes the specific settings of P1:

[0072] In P1, the scribing method can be an etching method or a laser scribing method.

[0073] When using laser scribing, the laser used is picosecond level, with a wavelength of 532nm green light, a frequency of 100KHz, a movement speed of 20mm / s, an output power of 80%-85%, and a scribing depth that is just enough to scratch the molybdenum.

[0074] When the laser scribing power is higher than the above power, the scribing depth will be deepened, which will increase the series resistance of the device and thus reduce the device's photoelectric performance. When the power is lower, the bottom Mo electrode will be connected or the Mo bottom electrode cannot be scratched, resulting in a resistance of less than 20MΩ across the two ends, which will increase the battery leakage and thus reduce the device's photoelectric performance.

[0075] Then use a multimeter to measure the resistance at both ends of the line, and use a step profiler to measure the depth of the line. The resistance at both ends of the line should be greater than 20MΩ, and the depth of the line should be between 800-1200nm. Failure to meet this standard indicates that the bottom electrode of the battery is not completely separated, which will reduce the performance of the device.

[0076] Example 3

[0077] This embodiment is used to illustrate the configuration of preparing a copper-zinc-tin-sulfur-selenium absorption layer on a molybdenum conductive layer:

[0078] The copper-zinc-selenium-sulfur absorption layer is a copper-zinc-tin-sulfur-selenium thin film doped with silver. The preparation steps are as follows:

[0079] Preparation of copper complex: Weigh 319.69g (4.2mol) of thiourea in 2000ml of deionized water, heat and stir to dissolve and maintain the solution temperature at 65°C. After the thiourea is completely dissolved, weigh 138.6g (1.4mol) of cuprous chloride and add it. After the cuprous chloride is completely dissolved, filter the mother liquor hot and let it stand to cool. Colorless transparent crystals precipitated in the filtrate are the target product, copper complex Cu(Tu)3Cl, which is filtered and dried.

[0080] Preparation of the tin complex: Measure 8.8 ml of tin tetrachloride into a sealed round-bottom flask. Use a syringe to draw 50 ml of DMSO solution and inject it into the sealed flask. A vigorous reaction will form a large amount of white precipitate. After the reaction is complete, filter the white precipitate, wash it several times with ethanol, and dry it to obtain the desired product, Sn(DMSO)4Cl4.

[0081] Preparation of the precursor solution: 8 mL of DMSO was measured and put into a reagent bottle, and 1.9 g (6.45 mmol) of copper complex Cu(Tu)3Cl, 0.092 g (0.645 mmol) of silver chloride, 1.667 g (4 mmol) of the prepared tin complex Sn(DMSO)4Cl4, 0.844 g (4.6 mmol) of zinc acetate, 0.3928 g of thiourea and 0.0034 g (0.0645 mmol) of sodium chloride were weighed and added to the reagent bottle in sequence and stirred at room temperature until completely dissolved to obtain the precursor solution ACZTS.

[0082] Preparation of a silver-copper-zinc-tin-sulfur (AgCuZnS) precursor film: Molybdenum glass, scribed P1, was ultrasonically cleaned in ethanol and ultrapure water for 15 minutes each, then dried. The precursor solution, ACZTS, was spin-coated in a glove box at a speed of 2000 rpm for 20 seconds. After spin coating, the sample was annealed on a hot plate at 370°C for 2 minutes. This spin-coating and heating process was repeated seven times to obtain a AgCuZnS precursor film.

[0083] Preparation of silver-copper-zinc-tin-sulfur-selenium thin film: The prepared silver-copper-zinc-tin-sulfur precursor film sample was placed in a graphite box, and about 0.5g of Se particles were weighed and placed symmetrically in the graphite box. The vacuum inside the tube was evacuated to a vacuum degree of 5×10 -2 After 1000 Torr, argon was introduced to atmospheric pressure. The vacuum and regassing operation was repeated three times to completely expel all water and oxygen (H2O and O2) from the tube to ensure that the selenization reaction occurred in a water- and oxygen-free atmosphere. The tube furnace heating program was started with a target temperature of 540°C and a heating rate of 2°C / s. The temperature was maintained at 540°C for 20 minutes. After the temperature was reached, the sample was naturally cooled to room temperature.

[0084] Example 4

[0085] This embodiment is used to illustrate the configuration of the cadmium sulfide buffer layer in Example 1:

[0086] The material of the cadmium sulfide buffer layer is selected from zinc oxysulfide or cadmium sulfide;

[0087] When the material of the buffer layer is cadmium sulfide, the specific preparation method is as follows:

[0088] Take out the selenized absorption layer film and soak it in deionized water for 3 minutes. After soaking, use chemical bath deposition (CBD) to deposit the CdS buffer layer. First, measure 150ml of ultrapure water and place it in a sandwich beaker. Fix the sample with a mold and place it in the sandwich beaker. Then, add 20ml of 1.65mmol / L CdSO4 aqueous solution and 28ml of ammonia water, stir, turn on the water pump, and pass hot water with a temperature of 65°C into the water bath beaker. After 1 minute, add 20ml of 0.825mol / L thiourea aqueous solution and deposit for 8 minutes. Finally, rinse the sample surface with deionized water to remove the cadmium sulfide particles adsorbed on the surface, and blow the sample dry with a nitrogen gun.

[0089] Example 5

[0090] This example illustrates the preparation of intrinsic zinc oxide;

[0091] In preparing an isolation layer of intrinsic zinc oxide on a cadmium sulfide buffer layer, the preparation method of intrinsic zinc oxide is as follows:

[0092] The preparation method of intrinsic zinc oxide is vacuum sputtering method, and the specific parameters are: under argon atmosphere, gas pressure 0.5Pa, sputtering power 80W, and film thickness 50nm.

[0093] Example 6

[0094] This embodiment clarifies the setting of P2:

[0095] The P2 can be scribed by mechanical or laser methods.

[0096] When mechanical scribing is used, a blade or mechanical scribing device is used to scribe the line to the molybdenum (i.e., the intrinsic zinc oxide window layer, cadmium sulfide buffer layer, CZTSSe absorption layer, and molybdenum selenide layer) on one side of P1 according to the design, so that it crosses the entire battery, thereby creating a channel that can connect the adjacent top and bottom electrodes.

[0097] When the scribing method is laser scribing, the laser used is picosecond level, with a wavelength of 532nm green light, a frequency of 100KHz, and a movement speed of 20mm / s. According to the design, on one side of P1, the line is scratched to the molybdenum (that is, the intrinsic zinc oxide window layer, the cadmium sulfide buffer layer, the CZTSSe absorption layer, and the molybdenum selenide layer are scratched). The line width is increased to 50-60 microns by 4 laser scribings (each time at an interval of 10 microns). If the value is higher than this, the series resistance will not be significantly reduced, while lowering this value will increase the series resistance.

[0098] In the present invention, the method for detecting whether the molybdenum selenide is scratched in step (5) is to use a probe station to detect the resistance between the inner part of the second scratched line and the bottom molybdenum. Preferably, the resistance should be in the ohm range. A resistance higher than this indicates the presence of molybdenum selenide or metal melt that has not been completely removed.

[0099] When performing P2 scribing, the following operations are performed to optimize the scribing effect: P2 scribing is divided into two steps: the first step uses a higher power to perform the initial scribing. This step scribing is performed until the MoSe layer is reached. Usually, this step will leave some MoSe and a certain amount of molten metal residue. Therefore, a second step with a lower power is added to achieve the purpose of cleaning. The optimization process is provided below:

[0100] Six thick lines were drawn using power levels of 20%, 25%, 30%, 35%, 40%, and 45%. (Each thick line consists of four thin lines drawn continuously with a laser at intervals of 10 microns, using 532nm green light.) The lines at 40% and 45% penetrated the Mo and transmitted light directly, without the need for further testing. The lines obtained at the remaining power levels were tested using a probe station, and the results are shown in Table 1.

[0101] Table 1 The line depth and resistance between the bottom of the line and the Mo electrode at different marking powers during the first P2 marking

[0102]

[0103] Table 1 shows that a power of 30% (4 lines) is sufficient to scribe the line to the Mo. However, some molten metal and MoSe may remain on the surface. Therefore, a second, lower-power laser pass can be used to clean the residue from the original P2 line. As shown in the left figure, the first line was scribed at 30% (4 lines, 0.01mm spacing). Then, the scribed line was cleaned at 0%, 19%, 20%, and 21% power levels. The resistance between these two lines and the bottom Mo was measured, and the data obtained are shown in Table 2.

[0104] Table 2 Line depth and line bottom and Mo electrode resistance corresponding to different powers of the second P2 cleaning and scribing

[0105]

[0106] As shown in Table 2, the minimum resistance value is obtained by using a power of 30+21%. 30+21% power is the best choice. When the power is increased from 21%, in addition to increasing energy consumption, the remaining molybdenum selenide may be less, and it is easy to cause damage to the electrode molybdenum, thus seriously affecting the performance of the product.

[0107] Example 7

[0108] This embodiment clarifies the setting of P3:

[0109] The scribing methods of P3 can be mechanical scribing, chemical etching scribing and laser scribing;

[0110] When mechanical scribing is used, a blade or mechanical scribing device is used to draw another line on the side of P2 away from P1 (i.e., to cut through the aluminum-doped zinc oxide, intrinsic zinc oxide, cadmium sulfide, and copper-zinc-tin-sulfur-selenium absorption layer), so that it crosses the entire battery and separates the top electrodes of adjacent batteries. In this way, the modular and integrated series structure of the battery is successfully realized;

[0111] like Figure 17When chemical etching is used, a layer of positive photoresist is spin-coated on the component surface. The first spin-coating speed is 500 rpm for 10 seconds, and the second spin-coating speed is 4000 rpm for 40 seconds. The layer is then cured at 150°C for 1 minute. The layer is then exposed to a 355nm UV laser to selectively expose specific areas of the photoresist according to the design, or a 365nm UV photolithography machine and mask are used to selectively expose specific areas of the photoresist. The layer is then developed with a developer and etched with an AZO etchant for 1 minute and 40 seconds. (If the etching time is too short, the top electrode will not be disconnected, and the resistance across the P3 line will not meet the requirements. If the etching time is too long, the P3 line will be too wide and lose optoelectronic performance. In severe cases, the AZO channel of the P2 line will be etched away, destroying the series structure of the cell.) Because the CZTSSe absorber layer is not easily corroded by hydrochloric acid, this method can specifically remove AZO, i-ZnO, and cadmium sulfide.

[0112] When the etching time of AZO etching solution is too short, the top electrode cannot be disconnected, and the resistance at both ends of the P3 line does not meet the requirements. If the etching time is too long, P3 will be too wide and lose the photoelectric performance. In severe cases, the AZO channel of P2 will be etched away, causing the series structure of the battery to be destroyed. The etching time is selected as 1min40s.

[0113] The formula of AZO etching solution is: the volume ratio is set to: dilute hydrochloric acid (volume fraction 36%-38%): water = 2:30 (that is, 2 ml of dilute hydrochloric acid mixed with 30 ml of water); when the concentration used is low, the etching time becomes longer, which is not conducive to improving production efficiency. When the concentration used is high, the reaction is too intense and is not conducive to line control.

[0114] After the P3 scribing process is completed, the method for testing P3 is: use a multimeter to test the resistance between the two ends of the P3 line. The resistance should be greater than 500Ω / cm 2 If the value is lower than this standard, it means that the top electrode of the battery is not completely separated or there is battery leakage.

[0115] Example 8

[0116] This embodiment is used to illustrate the preparation method of battery electrodes:

[0117] Using a knife, scrape out the molybdenum on the far left and far right sides;

[0118] The scraped-out molybdenum areas are then plated with indium to create the positive and negative electrodes.

[0119] Method to determine the positive and negative poles: Take any P1, then find the nearest P2, draw a perpendicular line perpendicular to P1 and P2, and the intersection points are A (intersection with P1) and B (intersection with P2). The electrode in the AB direction is the negative pole, and vice versa.

[0120] Example 9

[0121] This example is used to illustrate the preferred preparation sequence:

[0122] Possible line drawing method:

[0123] The marking method of P1 adopts the laser marking method described above;

[0124] The marking method of P2 adopts the mechanical marking method described above;

[0125] The P3 marking method adopts the mechanical marking method.

[0126] The resulting components are Figure 7 As shown,

[0127] Finally, the device efficiency is obtained, such as Figure 8 As shown. Open circuit voltage (V oc ) is the 2.26V short-circuit current (I sc ) is 38.6mA, the fill factor (FF) is 33.4%, the cell conversion efficiency is 1.74%, and the total cell area is 16cm 2

[0128] Two possible line drawing methods:

[0129] The marking method of P1 adopts the laser marking method described above;

[0130] The marking method of P2 adopts the laser marking method described above;

[0131] The P3 marking method adopts the mechanical marking method.

[0132] The resulting components are Figure 9 As shown,

[0133] Finally, the device efficiency is obtained, such as Figure 10 As shown. Open circuit voltage (V oc ) is 2.658V short-circuit current (I sc ) is 56.9mA, the fill factor (FF) is 49.2%, the cell conversion efficiency is 4.65%, and the total cell area is 16cm 2

[0134] There are three possible ways to draw lines:

[0135] The marking method of P1 adopts the laser marking method described above;

[0136] The marking method of P2 adopts the laser marking method described above;

[0137] The P3 scribing method adopts the scribing method of etching with the etching solution.

[0138] The resulting components are Figure 11 As shown,

[0139] Finally, the device efficiency is obtained, such as Figure 12 As shown. Open circuit voltage (V oc ) is 2.482V short-circuit current (I sc ) is 35.8mA, the fill factor (FF) is 25.1%, the cell conversion efficiency is 1.16%, and the total cell area is 16cm 2 .

[0140] Example 10

[0141] The electrical performance of the series-connected battery prepared by the marking method 3 in Example 9 is compared with that of the single-cell battery. Figure 16 and Figure 17 shown.

[0142] like Figure 16 As shown, the open-circuit voltage of a single cell is only 0.499V. Different methods will affect the final series efficiency, but the open-circuit voltages of these cells are all multiples of the single-cell open-circuit voltage, which conforms to the principle of increasing voltage in series circuits. The metallization of CZTSSe-based absorber layers during laser scribing requires further verification. Under current conditions, the optimal preparation processes are laser scribing for P1 and P2 and mechanical scribing for P3. In the future, once the characteristics and kinetic thermodynamics of the metallization of CZTSSe-based absorber layers during laser processing are clarified, laser scribing for P3 may be more advantageous.

[0143] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. A large-area copper-zinc-tin-sulfur-selenium solar cell module, characterized by: The battery components are arranged in layers, from bottom to top: soda-lime glass layer, molybdenum conductive layer, copper-zinc-tin-sulfur-selenium absorption layer, cadmium sulfide buffer layer, high resistance window layer, low resistance window layer; The method for preparing the large-area copper-zinc-tin-sulfur-selenium solar cell assembly comprises the following steps: (1) scribing a molybdenum-plated glass substrate to divide the molybdenum conductive layer according to a designed pattern; (2) preparing a copper, zinc, tin, sulfur and selenium absorption layer on the molybdenum conductive layer described in step (1); (3) preparing a cadmium sulfide buffer layer on the copper-zinc-tin-sulfur-selenium absorption layer described in step (2); (4) preparing a window layer of intrinsic zinc oxide on the cadmium sulfide buffer layer described in step (3); (5) scribing the thin film obtained in step (4) by a certain method, scribing according to the designed pattern, and scribing the line to the molybdenum, that is, cutting the intrinsic zinc oxide window layer, the cadmium sulfide buffer layer, and the copper-zinc-tin-sulfur-selenium absorption layer, thereby creating a channel connecting adjacent copper-zinc-tin-sulfur-selenium solar cells; (6) preparing a window layer of AZO or ITO on the film obtained in step (5), so that the top electrode and bottom electrode connection channel of adjacent cells are successfully created; (7) Scribing the thin film obtained in step (6) according to a certain method to divide the top electrode according to the design; this time, the AZO or ITO is removed according to different methods and the scribing line is drawn to the molybdenum; (8) using the thin film prepared in (7) to prepare a large-area copper-zinc-tin-sulfur-selenium thin film solar cell module after differentiating the electrodes; The scribing in step (5) includes: a first step of using a high power of 30% for preliminary scribing, the line being scribed to the molybdenum; a second step of using a low power of 21% for scribing, thereby cleaning the molybdenum selenide and the metal melt remaining after the first step of scribing; The marking methods in steps (1) (5) (7) are laser marking, laser marking, and mechanical marking, respectively.

2. The large-area copper-zinc-tin-sulfur-selenium solar cell assembly according to claim 1, characterized in that: The high-resistance window layer is intrinsic zinc oxide, and the low-resistance window layer is AZO or ITO.

3. The large-area copper-zinc-tin-sulfur-selenium solar cell assembly according to claim 1, characterized in that: The battery components are connected in series to form a battery pack.

4. The large-area copper-zinc-tin-sulfur-selenium solar cell assembly according to claim 1, characterized in that: There are a number of lines of varying depths in each layer of the battery assembly.

5. The large-area copper-zinc-tin-sulfur-selenium solar cell assembly according to claim 1, characterized in that: The copper-zinc-tin-sulfur-selenium absorption layer includes but is not limited to a copper-zinc-tin-sulfur-selenium absorption layer and various absorption layers doped with other elements, a copper-zinc-tin-sulfur absorption layer without selenium and various absorption layers obtained by doping with other elements, a copper-zinc-tin-sulfur absorption layer without sulfur and various absorption layers obtained by doping with other elements.

6. Use of the large-area copper-zinc-tin-sulfur-selenium solar cell assembly according to claim 1 in the preparation of solar cells.

7. Use of the large-area copper-zinc-tin-sulfur-selenium solar cell assembly according to claim 6 in the preparation of solar cells, characterized in that: The large-area copper-zinc-tin-sulfur-selenium thin film battery achieves an increase in the area of ​​the component by connecting in series.

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