Developing solution, preparation method and application of negative photoresist glue for perovskite battery

Abstract

The application discloses a developing solution, a preparation method and an application of a negative photoresist glue for a perovskite battery, and ingredients of the developing solution include dimethylcyclohexanone 25-35%, dimethylformamide 50-60% and petroleum ether 5-15% in percentage by weight. The ingredients in the developing solution are widely sourced, the dimethylcyclohexanone has low toxicity, the dimethylformamide is a widely used chemical raw material, and the petroleum ether is a light petroleum product, and the three have low cost and low toxicity, and the use of the three has no harm to the human body. By adjusting the concentration of the dimethylcyclohexanone and the dimethylformamide in the petroleum ether, the mixture of the three is stable to the developing performance of the negative photoresist glue, and the situation that incomplete development leads to surface residual photoresist glue and excessive development causes the photoresist glue lines to be excessively dissolved by the developing solution, thereby leading to poor filling effect is solved.

Description

Technical Field

[0001] This application relates to the field of semiconductor device technology that is sensitive to infrared radiation, light, shorter wavelength electromagnetic radiation, or particle radiation, and is specifically suitable for converting such radiation energy into electrical energy, or specifically suitable for controlling electrical energy through such radiation. Specifically, it relates to a developer, preparation method, and application of a negative photoresist for perovskite solar cells. Background Technology

[0002] Photoresists are divided into two categories: negative photoresists and positive photoresists. After exposure and development, the exposed portions of positive photoresists are removed, while the exposed portions of negative photoresists are retained after development. Positive photoresists are generally used for film etching. After exposure, development, and etching, the unremoved portions are removed during the film stripping process. Positive photoresists are only used temporarily during processing and are not present in the final product. Negative photoresists, on the other hand, are part of the product structure and are ultimately retained on the product. To improve resolution, almost every type of photoresist is equipped with a dedicated developer to ensure optimal development results.

[0003] In the fabrication of perovskite solar cells, three laser processing steps are required to achieve a certain voltage output: P1, etching the front electrode layer; P2, etching the perovskite functional film layer and filling it with a metal conductive layer; and P3, etching the back electrode layer. Through these three laser processing steps, the perovskite cell forms a series-connected sub-cell structure, thus achieving a specific voltage output. The P1 laser etching process requires filling with photoresist to prevent short circuits and increase cell reliability. Secondly, tiny pinholes can form in the perovskite layer during fabrication; these defects can cause short circuits between the top and bottom electrodes. Furthermore, the perovskite absorber layer is easily contaminated and corroded by dust and moisture; filling it with photoresist can prevent such contamination.

[0004] After photoresist is filled and cured by exposure, excess photoresist needs to be removed by developing. Commonly used developing solutions for positive photoresist include aqueous solutions of KOH, TMAH, and NaOH; for negative photoresist, aqueous solutions of KOH or Na2CO3 are generally used, with surfactants added to improve the hydrophilicity of the developing solution. Some also use aqueous solutions of H2O2 directly. However, perovskite materials are organic-inorganic hybrid materials with unstable chemical properties, easily decomposing under the influence of water, oxygen, heat, and light. Especially when water vapor reaches the surface of the perovskite film, the combined effect of water and oxygen causes rapid decomposition of the perovskite film surface, ultimately leading to a decrease in the performance of the perovskite battery. Therefore, the aforementioned developing solutions cannot be used for perovskite batteries.

[0005] Currently, domestic and foreign manufacturers generally use acetone or toluene, chlorobenzene, and xylene as developers for perovskite solar cells. However, these components have problems such as poor development stability, which may result in incomplete development and residual photoresist on the surface; overdevelopment, where the photoresist lines are excessively dissolved by the developer, resulting in poor filling effect; and high toxicity, which poses a significant risk to human health, with long-term use leading to chronic poisoning and other negative effects. Summary of the Invention

[0006] This invention aims to at least solve one of the technical problems existing in the prior art. To this end, this invention proposes a developer solution that is less harmful, lower in cost, and provides stable developing results. The technical solution adopted includes: A developer for a negative photoresist used in perovskite solar cells, wherein the developer comprises, by weight percentage: Dimethylcyclohexanone 25%~35%; Dimethylformamide 50%~60%; Petroleum ether 5%~15%.

[0007] One embodiment of the present invention addresses its technical problem by comprising, by weight percentage: [The following is a technical solution, not part of the technical solution description:] 25% dimethylcyclohexanone; Dimethylformamide 60%; 15% petroleum ether.

[0008] One embodiment of the present invention addresses its technical problem by comprising, by weight percentage: [The following is a technical solution, not part of the technical solution description:] Dimethylcyclohexanone 35%; Dimethylformamide 50%; 15% petroleum ether.

[0009] One embodiment of the present invention addresses its technical problem by comprising, by weight percentage: [The following is a technical solution, not part of the technical solution description:] Dimethylcyclohexanone 35%; Dimethylformamide 60%; 5% petroleum ether.

[0010] This application also proposes a method for preparing a developer for a negative photoresist used in perovskite solar cells, comprising: Step 1: Weigh out dimethylcyclohexanone, dimethylformamide, and petroleum ether according to the weight percentage of the components in the developer solution; Step 2: Add dimethylcyclohexanone to the mixing tank, add petroleum ether while stirring, and then add dimethylformamide while stirring. Stir the mixture until it is homogeneous. Step 3: Pass the mixture through a filter to obtain the developing solution.

[0011] One embodiment of the present invention uses the following technical solution to solve its technical problem: the microfiltration membrane pore size of the filter in step 3 is 0.1μm~0.25μm.

[0012] One embodiment of the present invention adopts the following technical solution to solve its technical problem: Step 3 is carried out in a Class 100 cleanroom environment with no more than 100 particles larger than 0.5 μm per cubic foot of air.

[0013] This application also proposes the application of the developer in the fabrication of perovskite solar cells, including: Step 1: Fabricate a front electrode layer on the substrate and etch a P1 trench on the front electrode layer. Fabricate a negative photoresist layer on the front electrode layer to fill the P1 trench. Expose and cure the negative photoresist in the P1 trench. Use the developing solution as described in claim 1 to develop and clean the negative photoresist on the front electrode layer. Step 2: Sequentially fabricate the first transport layer, the perovskite layer, the second transport layer, and the back electrode layer on the front electrode layer. Then, fabricate a negative photoresist layer on the back electrode layer, fill the pinholes, and expose and cure it. Use the aforementioned developer to develop and clean the negative photoresist on the back electrode layer to obtain the perovskite solar cell.

[0014] The beneficial effects of this invention are: In the developing solution of the negative photoresist for perovskite solar cells described in this application, dimethylcyclohexanone is a widely used pharmaceutical intermediate that can be used in drug synthesis and has low toxicity; dimethylformamide is a widely used chemical raw material; and petroleum ether is a light petroleum product. All three are widely available, low in cost, and low in toxicity, and their use is harmless to the human body. Furthermore, by adjusting the concentrations of dimethylcyclohexanone and dimethylformamide in petroleum ether, the mixture of the three substances was made to stabilize the development performance of negative photoresist, thus solving the problems of incomplete development leading to residual photoresist on the surface and over-development causing the photoresist lines to be excessively dissolved by the developer, resulting in poor filling effect. Attached Figure Description

[0015] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which: Figure 1 This is a schematic diagram of the state in step 1 of embodiment 3 of this application. Figure 1 ; Figure 2 This is a schematic diagram of the state in step 1 of embodiment 3 of this application. Figure 2 ; Figure 3 This is a schematic diagram of the state in step 1 of embodiment 3 of this application. Figure 3 ; Figure 4This is a schematic diagram of the state in step 2 of embodiment 3 of this application. Figure 1 ; Figure 5 This is a schematic diagram of the state in step 2 of embodiment 3 of this application. Figure 2 ; Figure 6 This is a schematic diagram of the state in step 2 of embodiment 3 of this application. Figure 3 . Detailed Implementation

[0016] This section will describe in detail specific embodiments of the present invention. Preferred embodiments of the present invention are shown in the accompanying drawings. The purpose of the drawings is to supplement the textual description with graphics, so that people can intuitively and vividly understand each technical feature and overall technical solution of the present invention, but they should not be construed as limiting the scope of protection of the present invention.

[0017] In this invention, unless otherwise explicitly defined, the terms "setting," "installing," and "connecting" should be interpreted broadly. For example, they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to a fixed connection, a detachable connection, or an integrally formed connection; they can refer to a mechanical connection; they can refer to the internal connection of two components or the interaction between two components. Those skilled in the art can reasonably determine the specific meaning of the above terms in this invention in conjunction with the specific content of the technical solution.

[0018] Example 1 This application discloses a developer for a negative photoresist used in perovskite solar cells. The components of the developer, by weight percentage, include: Dimethylcyclohexanone 25%~35%; Dimethylformamide 50%~60%; Petroleum ether 5%~15%.

[0019] The developer in this application is petroleum ether with added dimethylcyclohexanone and dimethylformamide. Dimethylcyclohexanone and dimethylformamide can dissolve negative photoresist respectively. Dissolving both dimethylcyclohexanone and dimethylformamide in petroleum ether in a certain proportion can effectively develop negative photoresist, avoiding and solving the problems of incomplete development leading to residual photoresist on the surface and over-development causing the photoresist lines to be excessively dissolved by the developer, resulting in poor filling effect.

[0020] Example 2 Based on the embodiments, a method for preparing a developer for a negative photoresist used in perovskite solar cells is proposed, comprising: Step 1: Weigh out dimethylcyclohexanone, dimethylformamide, and petroleum ether according to the weight percentage of the components in the developer solution; Step 2: Add dimethylcyclohexanone to the mixing tank, add petroleum ether while stirring, and then add dimethylformamide while stirring. Stir the mixture until it is homogeneous. Step 3: Pass the mixture through a filter to obtain the developing solution.

[0021] Specifically, the microfiltration membrane of the filter in step 3 has a pore size of 0.1μm to 0.25μm. Step 3 is carried out in a Class 100 cleanroom environment with no more than 100 particles larger than 0.5μm per cubic foot of air, which can effectively prevent the developer from mixing into the developer and affecting the developing effect.

[0022] Example 3 Based on the developer disclosed in Example 1, this example proposes the application of the developer in the fabrication of perovskite solar cells, including: Step 1, refer to Figure 1-3 As shown, a front electrode layer 102 is fabricated on the substrate 101, and a P1 trench 103 is etched on the front electrode layer 102. A negative photoresist layer is fabricated on the front electrode layer 102 to fill the P1 trench 103. The negative photoresist in the P1 trench 103 is exposed and cured. The negative photoresist on the front electrode layer 102 is developed and cleaned using the developing solution described in Example 1. Step 2, refer to Figure 4-6 As shown, a first transport layer 104, a perovskite layer 105, a second transport layer 106, and a back electrode layer 107 are sequentially fabricated on the front electrode layer 102. A negative photoresist layer is fabricated on the back electrode layer 107 and filled with pinholes 108 before exposure and curing. The negative photoresist on the back electrode layer 107 is developed and cleaned using the developing solution described in Example 1 to obtain a perovskite solar cell.

[0023] The developer in steps 1 and 2 consists of 25% dimethylcyclohexanone, 60% dimethylformamide, and 15% petroleum ether by weight percentage. The development is complete, with no residual photoresist or overdevelopment on the surface, and the filling effect is good.

[0024] Example 4 The difference between Example 4 and Example 3 is that the developer in Step 1 and Step 2 contains 35% dimethylcyclohexanone, 50% dimethylformamide and 15% petroleum ether by weight percentage. The development is complete, there is no residual photoresist on the surface, no over-development, and the filling effect is good.

[0025] Example 5 The difference between Example 5 and Example 3 is that the developer in steps 1 and 2 contains 35% dimethylcyclohexanone, 60% dimethylformamide and 5% petroleum ether by weight percentage. The development is complete, with no residual photoresist on the surface, no over-development, and good filling effect.

[0026] Comparative Example 1 The difference between Comparative Example 1 and Example 4 is that the developer in steps 1 and 2 contains 15% dimethylcyclohexanone, 70% dimethylformamide and 15% petroleum ether by weight percentage, resulting in incomplete development and residual photoresist on the surface.

[0027] Comparative Example 2 The difference between Comparative Example 2 and Example 4 is that the developer in steps 1 and 2 contains 45% dimethylcyclohexanone, 40% dimethylformamide and 15% petroleum ether by weight percentage. Due to overdevelopment, the photoresist in the exposed and cured P1 trench 103 and pinhole 108 is overly dissolved by the developer, resulting in poor filling effect.

[0028] Of course, the present invention is not limited to the above-described embodiments. Those skilled in the art can make equivalent modifications or substitutions without departing from the spirit of the present invention. All such equivalent modifications and substitutions are included within the scope defined by the claims of this application.

Claims

1. A developing solution for a negative photoresist used in perovskite solar cells, characterized in that, The components of the developer, by weight percentage, include: Dimethylcyclohexanone 25%~35%; Dimethylformamide 50%~60%; Petroleum ether 5%~15%.

2. The developing solution for the negative photoresist used in perovskite solar cells according to claim 1, characterized in that, The components of the developer, by weight percentage, include: 25% dimethylcyclohexanone; Dimethylformamide 60%; 15% petroleum ether.

3. The developing solution for the negative photoresist used in perovskite solar cells according to claim 1, characterized in that, The components of the developer, by weight percentage, include: Dimethylcyclohexanone 35%; Dimethylformamide 50%; 15% petroleum ether.

4. The developing solution for the negative photoresist used in perovskite solar cells according to claim 1, characterized in that, The components of the developer, by weight percentage, include: Dimethylcyclohexanone 35%; Dimethylformamide 60%; 5% petroleum ether.

5. A method for preparing a developer for a negative photoresist for perovskite solar cells as described in any one of claims 1-4, characterized in that, include: Step 1: Weigh out dimethylcyclohexanone, dimethylformamide, and petroleum ether according to the weight percentage of the components in the developer solution; Step 2: Add dimethylcyclohexanone to the mixing tank, add petroleum ether while stirring, and then add dimethylformamide while stirring. Stir the mixture until it is homogeneous. Step 3: Pass the mixture through a filter to obtain the developing solution.

6. The method for preparing the developing solution of the negative photoresist for perovskite solar cells according to claim 5, characterized in that, The microfiltration membrane of the filter in step 3 has a pore size of 0.1 μm to 0.25 μm.

7. The method for preparing the developing solution of the negative photoresist for perovskite solar cells according to claim 5, characterized in that, Step 3 is performed in a Class 100 cleanroom environment with no more than 100 particles larger than 0.5 μm per cubic foot of air.

8. The application of the developer as described in any one of claims 1-4 in the fabrication of perovskite solar cells, characterized in that, include: Step 1: A front electrode layer (102) is fabricated on a substrate (101), and a P1 trench (103) is etched on the front electrode layer (102). A negative photoresist layer is fabricated on the front electrode layer (102) to fill the P1 trench (103). The negative photoresist in the P1 trench (103) is exposed and cured. The negative photoresist on the front electrode layer (102) is developed and cleaned using the developer solution as described in claim 1. Step 2: Sequentially fabricate a first transport layer (104), a perovskite layer (105), a second transport layer (106), and a back electrode layer (107) on the front electrode layer (102). After fabricating a negative photoresist layer on the back electrode layer (107) and filling the pinholes (108), expose and cure it. Use the developer solution as described in claim 1 to develop and clean the negative photoresist on the back electrode layer (107) to obtain a perovskite solar cell.

Images