Perovskite light-emitting microarray and preparation method and application thereof

Abstract

The invention relates to a perovskite light-emitting microarray and a preparation method and application thereof. According to the preparation method, when a second metal halide perovskite is formed on a monochromatic perovskite light-emitting microarray on which a first metal halide perovskite is formed, a photoetching process is not adopted, and an ink-jet printing process is also not depended; the polymer layer is formed through annealing, and laser etching and orthogonal solvent design are matched, so that the situation that the precision of the first metal halide perovskite is reduced due to the fact that the first metal halide perovskite is damaged when the second metal halide perovskite is formed is effectively avoided. Meanwhile, a polymer layer is formed through annealing, a precise template can be prepared through laser etching, and then the precise template is matched with orthogonal solvent design, so that the second metal halide perovskite has high precision and has no obvious edge diffusion or adjacent pixel crosstalk phenomenon. According to the preparation method disclosed by the invention, metal halide perovskite with different light emitting colors can be integrated on the same substrate.

Description

Technical Field

[0001] The present invention relates to the technical field of luminescent microarrays, and more specifically, to a perovskite luminescent microarray and a preparation method and application thereof. Background Art

[0002] Luminescent microarrays are the fundamental building blocks of full-color Micro-LED displays, and technological advancements have directly driven improvements in full-color display performance and expanded applications. One approach to achieving full-color, high-resolution Micro-LED displays is based on red, green, and blue (RGB) micro-LED chips. However, growing different-color microarrays on the same substrate is extremely difficult, posing significant technical challenges in efficiency, precision, and yield control during the mass transfer process.

[0003] The selection of materials for light-emitting microarrays is another major challenge. Traditional semiconductor materials (such as III-V semiconductors) suffer from high costs, insufficient color purity, and limited luminous efficiency and brightness. These limitations restrict their application and development in high-performance Micro-LED display technology.

[0004] In recent years, metal halide perovskites have attracted widespread attention from researchers due to their advantages such as high photoluminescence quantum yield, wide color gamut coverage, high color purity, and short fluorescence lifetime. One of the existing technical means is to use photolithography to form metal halide perovskites on a substrate. However, as soft ionic compounds, metal halide perovskites are extremely sensitive to high-energy ultraviolet light and developer solvents in the photolithography process. After preparing a metal halide perovskite array of the first color on a substrate, if a photoresist is used to make a metal halide perovskite array template of the second color, the high-energy ultraviolet light will damage the metal halide perovskite array of the first color. At the same time, the developer used for photoresist development will come into contact with the metal halide perovskite array of the first color, causing a certain degree of damage to the metal halide perovskite array of the first color, thereby affecting the precision of the metal halide perovskite array of the first color. In addition, the photolithography process includes multiple steps such as primer coating, spin coating of photoresist, soft baking, alignment exposure, post-baking, development, hard baking, and etching. The process is complex and the preparation cost is high.

[0005] There is also existing technology that uses inkjet printing to form a second color metal halide perovskite array. It can directly deposit functional ink onto the target substrate, thereby preventing the metal halide perovskite from coming into contact with the developer and being destroyed. However, inkjet printing technology is prone to the coffee ring effect, and when using an electrically driven inkjet printing method, halogen ions are prone to migration under the action of a high electric field, resulting in a change in the emission peak position.

[0006] Therefore, it is necessary to develop new technologies that do not rely on photolithography (photoresist) and inkjet printing processes to achieve patterning of metal halide perovskite materials with high pattern accuracy and the ability to integrate metal halide perovskites of different luminescent colors on the same substrate. Summary of the Invention

[0007] The primary purpose of the present invention is to overcome the problems of the above-mentioned existing technologies that it is difficult to integrate metal halide perovskites of different luminescent colors on the same substrate, or the photolithography process has many and complex steps, which can easily have a negative impact on the precision of the metal halide perovskite array, or rely on inkjet printing technology to form metal halide perovskite arrays of multiple luminescent colors, and to provide a method for preparing a perovskite light-emitting microarray.

[0008] A further object of the present invention is to provide a perovskite light-emitting microarray.

[0009] Another object of the present invention is to provide an application of a perovskite light-emitting microarray in the preparation of a full-color Micro-LED display.

[0010] The above-mentioned purpose of the present invention is achieved through the following technical solutions: A method for preparing a perovskite light-emitting microarray comprises the following steps: S1. forming a first metal halide perovskite on a substrate to obtain a monochrome perovskite light-emitting microarray; S2. coating a polymer solution on a single-color perovskite light-emitting microarray, annealing to form a polymer layer, and laser etching the polymer layer to form a second array template; S3. adding a second metal halide perovskite precursor solution to the second array template, annealing to form a second metal halide perovskite, and then removing the polymer layer to obtain a perovskite light-emitting microarray; The solvent of the second metal halide perovskite precursor solution and the solvent of the polymer solution are orthogonal solvents.

[0011] The present invention does not use a photolithography process or rely on an inkjet printing process when forming a second metal halide perovskite on a monochrome perovskite light-emitting microarray formed with a first metal halide perovskite. Instead, it forms a polymer layer through annealing (removing the solvent of the polymer solution), laser etching, and orthogonal solvent design. This effectively avoids damaging the first metal halide perovskite during the formation of the second metal halide perovskite, thereby avoiding reducing the precision of the first metal halide perovskite.

[0012] Furthermore, by annealing the polymer layer and laser etching, a precise template can be created. Combined with orthogonal solvent design, this allows for high-precision second-metal halide perovskites with no noticeable edge diffusion or crosstalk between adjacent pixels. Furthermore, eliminating the need for photoresist can mitigate the high cost associated with expensive photoresists.

[0013] The preparation method of the present invention can also integrate metal halide perovskites of different luminescent colors on the same substrate while maintaining the high precision of different metal halide perovskites, providing a new preparation process for full-color Micro-LED displays.

[0014] In addition, the preparation method of the present invention has simple process, low equipment cost and low operation difficulty.

[0015] It should be understood that the luminescent colors of the first metal halide perovskite and the second metal halide perovskite can be the same or different. When the luminescent colors are the same, the resulting perovskite luminescent microarray is a single-color perovskite luminescent microarray; when the luminescent colors are different, the resulting perovskite luminescent microarray is a dual-color perovskite luminescent microarray.

[0016] Preferably, the substrate is a conductive substrate.

[0017] More preferably, the conductive substrate is at least one of an indium tin oxide glass substrate and an indium tin oxide flexible substrate.

[0018] Preferably, the polymer in the polymer solution is at least one of polystyrene, polymethyl methacrylate or polycarbonate.

[0019] More preferably, the polymer in the polymer solution is at least one of polystyrene or polymethyl methacrylate.

[0020] The polymer in the polymer solution is polystyrene or polymethyl methacrylate, which is more conducive to forming a continuous and dense polymer layer after annealing, thereby further improving the accuracy of the template and further improving the accuracy of the metal halide perovskite.

[0021] Preferably, the solvent of the polymer solution is at least one of toluene, chlorobenzene or dichloromethane.

[0022] Preferably, the concentration of the polymer solution is 0.1-1 g / mL.

[0023] Controlling the concentration of the polymer solution within this range is more conducive to forming a continuous and dense polymer layer after annealing, thereby further improving the accuracy of the template and further improving the accuracy of the metal halide perovskite.

[0024] Preferably, the annealing temperature in each step is 80-100° C., and the annealing time is 10-20 min.

[0025] In step S2, the annealing temperature is controlled within this range, which is more conducive to forming a continuous and dense polymer layer after annealing, thereby further improving the accuracy of the template and further improving the accuracy of the metal halide perovskite.

[0026] The process of forming the first metal halide perovskite in step S1 may adopt an existing process, such as a photolithography (photoresist) process, or other processes that can form a metal halide perovskite array.

[0027] Preferably, the specific process in step S1 is: coating a polymer solution on a substrate, annealing to remove the solvent of the polymer solution to form a polymer layer, and laser etching the polymer layer to form a first array template; adding a first metal halide perovskite precursor solution to the first array template, annealing to form a first metal halide perovskite, and then removing the polymer layer to obtain a monochrome perovskite light-emitting microarray; The solvent of the first metal halide perovskite precursor solution and the solvent of the polymer solution are orthogonal solvents.

[0028] The above process is used to form the first metal halide perovskite, which does not rely on the photolithography (photoresist) process and avoids the use of expensive photoresist, thus lowering the cost of the preparation process.

[0029] More preferably, the solvent of the first metal halide perovskite precursor solution is at least one of dimethyl sulfoxide, dimethylformamide or γ-butyrolactone.

[0030] Preferably, the chemical formula of the first metal halide perovskite is MPbBr3, (PEA)2N n-1 Pb n Br 3n+1 , LPbI3 or KPbIBr2; wherein, the M is at least one of methylammonium cation (MA), Cs or formamidinium cation (FA); the N is at least one of methylammonium cation, Cs or formamidinium cation; the L is at least one of Cs or formamidinium cation; the K is a methylammonium cation; and the n is an integer greater than or equal to 1.

[0031] More preferably, the first metal halide perovskite is MAPbBr3, CsPbBr3, FAPbBr3, (PEA)2MA n-1 Pb n Br 3n+1 、(PEA)2Cs n-1 Pb n Br 3n+1 、(PEA)2FAn-1 Pb n Br 3n+1 , at least one of CsPbI3, FAPbI3 or MAPbIBr2.

[0032] Further preferably, the first metal halide perovskite is at least one of MAPbBr3, CsPbBr3, and FAPbBr3.

[0033] Preferably, the luminescent color of the first metal halide perovskite is green.

[0034] Preferably, the chemical formula of the second metal halide perovskite is MPbBr3, (PEA)2N n-1 Pb n Br 3n+1 , LPbI3 or KPbIBr2; wherein, the M is at least one of methylammonium cation (MA), Cs or formamidinium cation (FA); the N is at least one of methylammonium cation, Cs or formamidinium cation; the L is at least one of Cs or formamidinium cation; the K is a methylammonium cation; and the n is an integer greater than or equal to 1.

[0035] More preferably, the second metal halide perovskite is MAPbBr3, CsPbBr3, FAPbBr3, (PEA)2MA n-1 Pb n Br 3n+1 、(PEA)2Cs n-1 Pb n Br 3n+1 、(PEA)2FA n-1 Pb n Br 3n+1 , at least one of CsPbI3, FAPbI3 or MAPbIBr2.

[0036] Further preferably, the second metal halide perovskite is (PEA)2MA n-1 Pb n Br 3n+1 、(PEA)2Cs n- 1Pb n Br 3n+1 or (PEA) 2FA n-1 Pb n Br 3n+1 At least one of .

[0037] Preferably, the luminescent color of the second metal halide perovskite is blue.

[0038] Preferably, the solvent of the second metal halide perovskite precursor solution is at least one of dimethyl sulfoxide, dimethylformamide or γ-butyrolactone.

[0039] Preferably, the perovskite light-emitting microarray obtained in step S3 is a dual-color perovskite light-emitting microarray, and the preparation method further comprises steps S4 and S5: S4. coating a polymer solution on the dual-color perovskite light-emitting microarray, annealing to form a polymer layer, and laser etching the polymer layer to form a third array template; S5. adding a third metal halide perovskite precursor solution to the third array template, annealing to form the third metal halide perovskite, and then removing the polymer layer to obtain a perovskite light-emitting microarray; The solvent of the third metal halide perovskite precursor solution and the solvent of the polymer solution are orthogonal solvents.

[0040] The first metal halide perovskite, the second metal halide perovskite, and the third metal halide perovskite may emit light of the same or different colors. When the first metal halide perovskite, the second metal halide perovskite, and the third metal halide perovskite emit light of the same color, the resulting perovskite light-emitting microarray is a single-color perovskite light-emitting microarray; when the first metal halide perovskite, the second metal halide perovskite, and the third metal halide perovskite emit light of different colors, the resulting perovskite light-emitting microarray is a three-color perovskite light-emitting microarray.

[0041] More preferably, the chemical formula of the third metal halide perovskite is MPbBr3, (PEA)2N n-1 Pb n Br 3n+1 , LPbI3 or KPbIBr2; wherein, the M is at least one of methylammonium cation (MA), Cs or formamidinium cation (FA); the N is at least one of methylammonium cation, Cs or formamidinium cation; the L is at least one of Cs or formamidinium cation; the K is a methylammonium cation; and the n is an integer greater than or equal to 1.

[0042] Further preferably, the third metal halide perovskite is MAPbBr3, CsPbBr3, FAPbBr3, (PEA)2MA n-1 Pb n Br 3n+1 、(PEA)2Cs n-1 Pb n Br 3n+1 、(PEA)2FA n-1 Pb n Br 3n+1, at least one of CsPbI3, FAPbI3 or MAPbIBr2.

[0043] Further preferably, the third metal halide perovskite is at least one of CsPbI3, FAPbI3 or MAPbIBr2.

[0044] More preferably, the luminescent color of the third metal halide perovskite is red.

[0045] More preferably, the solvent of the third metal halide perovskite precursor solution is at least one of dimethyl sulfoxide, dimethylformamide or γ-butyrolactone.

[0046] Preferably, the polymer layer is removed by dissolving with a solvent, and the solvent is at least one of toluene, chlorobenzene or dichloromethane.

[0047] Preferably, the laser etching conditions include: laser etching power of 0.2-30 W, wavelength of 365-1065 nm, and temperature of 0-50° C.

[0048] Preferably, the number of columns of the first array template is ≥1.

[0049] The present invention also protects a perovskite light-emitting microarray, which is prepared by the above preparation method.

[0050] The present invention also protects the use of the above-mentioned perovskite light-emitting microarray in the preparation of a full-color Micro-LED display.

[0051] Compared with the prior art, the present invention has the following beneficial effects: The present invention does not use a photolithography process or rely on an inkjet printing process when forming a second metal halide perovskite on a monochrome perovskite light-emitting microarray formed with a first metal halide perovskite. Instead, it forms a polymer layer through annealing (removing the solvent of the polymer solution), laser etching, and orthogonal solvent design. This effectively avoids damaging the first metal halide perovskite during the formation of the second metal halide perovskite, thereby avoiding reducing the precision of the first metal halide perovskite.

[0052] Furthermore, by annealing the polymer layer and laser etching, a precise template can be created. Combined with orthogonal solvent design, this allows for high-precision second-metal halide perovskites with no noticeable edge diffusion or crosstalk between adjacent pixels. Furthermore, eliminating the need for photoresist can mitigate the high cost associated with expensive photoresists.

[0053] The preparation method of the present invention can also integrate metal halide perovskites of different luminescent colors on the same substrate while maintaining high precision, providing a new preparation process for full-color Micro-LED displays. Furthermore, the preparation method of the present invention is simple, with low equipment cost and operational difficulty. BRIEF DESCRIPTION OF THE DRAWINGS

[0054] Figure 1 This is a photo of the dual-color perovskite light-emitting microarray prepared in Example 1. DETAILED DESCRIPTION

[0055] In order to more clearly and completely describe the technical solution of the present invention, the present invention is further described in detail through specific embodiments below. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention. Various changes can be made within the scope of the rights of the present invention.

[0056] Example 1 This embodiment provides a method for preparing a dual-color perovskite light-emitting microarray, comprising the following steps: (1) Two metal halide perovskite precursor solutions and polymer solutions with different emission wavelengths were prepared, wherein the solvent of the first metal halide perovskite precursor solution was DMSO, and the solutes were MABr and PbBr2 in a molar ratio of 1:1. After annealing, the first metal halide perovskite precursor solution became MAPbBr3, which emitted green light. The solvent of the second metal halide perovskite precursor solution was DMSO, and the solutes were PEABr, MABr and PbBr2 in a molar ratio of 2:1:2. After annealing, the second metal halide perovskite precursor solution became (PEA)2MAPb2Br7, which emitted blue light. The polymer in the polymer solution was polystyrene, the solvent was toluene, and the concentration of the polymer solution was 0.1 g / mL.

[0057] (2) 0.05 mL of the polymer solution prepared in step (1) was added dropwise onto an ITO glass substrate (1.5 cm × 1.5 cm block). After spin coating in a slurry coater, the polymer solution was annealed at 80°C for 10 minutes to remove the solvent to form a polymer layer having a thickness of approximately 100 nm. The polymer layer was then laser etched (power 2 W, wavelength 1065 nm, temperature 25°C) to form small pores that could accommodate liquids, thereby obtaining a first array template. (3) adding a first metal halide perovskite precursor solution dropwise onto the first array template of step (2), using a spin coater to spin coat the first metal halide perovskite precursor solution to fill the small holes, annealing at 80°C for 10 minutes to form the first metal halide perovskite, then placing it in toluene to remove the polymer layer, heating to volatilize the toluene, and obtaining a monochrome perovskite light-emitting microarray; (4) 0.05 mL of the polymer solution of step (1) was added dropwise onto the monochrome perovskite light-emitting microarray, and after spin coating in a gel coater, the polymer solution was annealed at 80°C for 10 minutes to remove the solvent to form a polymer layer with a thickness of about 100 nm. The polymer layer was then laser etched (power 2 W, wavelength 1065 nm, temperature 25°C) to form small holes that could accommodate liquid, thereby obtaining a second array template; (5) Add a second metal halide perovskite precursor solution onto the second array template of step (4), use a spin coater to spin coat the second metal halide perovskite precursor solution to fill the small holes, anneal at 80°C for 10 minutes to form a second metal halide perovskite, then place it in toluene to remove the polymer layer, heat to volatilize the toluene, and obtain a two-color perovskite light-emitting microarray.

[0058] The photo of the dual-color perovskite light-emitting microarray prepared in this example is shown in FIG. Figure 1 As shown. Figure 1 It can be seen that the first metal halide perovskite and the second metal halide perovskite of the two-color perovskite light-emitting microarray prepared in this embodiment both present a highly uniform periodic arrangement, the size of each unit is highly consistent and the boundaries are clear, and there is no obvious edge diffusion or crosstalk between adjacent pixels. This shows that the perovskite light-emitting microarray prepared in Example 1 has excellent graphic accuracy and pixel yield.

[0059] Example 2 This embodiment provides a method for preparing a dual-color perovskite light-emitting microarray. The difference from Example 1 is that in step (1), the DMSO solvent of the first metal halide perovskite precursor solution is replaced by DMF; and the DMSO solvent of the second metal halide perovskite precursor solution is replaced by DMF.

[0060] Example 3 This embodiment provides a method for preparing a dual-color perovskite light-emitting microarray. The difference from Example 1 is that in step (1), the toluene in the polymer solution is replaced by chlorobenzene; and in steps (3) and (5), the toluene used to remove the polymer layer is replaced by chlorobenzene.

[0061] Example 4 This embodiment provides a method for preparing a dual-color perovskite light-emitting microarray. The difference from Example 1 is that in step (1), the polystyrene in the polymer solution is replaced by polymethyl methacrylate.

[0062] Example 5 This embodiment provides a method for preparing a dual-color perovskite light-emitting microarray. The difference from Example 1 is that in step (1), the concentration of the polymer solution is 0.5 g / mL.

[0063] Example 6 This embodiment provides a method for preparing a dual-color perovskite light-emitting microarray. The difference from Example 1 is that in steps (2), (4) and (6), the power of the laser etching is 10 W.

[0064] Example 7 This embodiment provides a method for preparing a three-color perovskite light-emitting microarray, which differs from embodiment 1 in that it further includes steps (6) and (7): (6) 0.05 mL of the polymer solution of step (1) was added dropwise onto the dual-color perovskite light-emitting microarray, and after spin coating in a gel coater, the polymer solution was annealed at 80°C for 10 minutes to remove the solvent to form a polymer layer with a thickness of about 100 nm. The polymer layer was then laser etched (power 2 W, wavelength 1065 nm, temperature 25°C) to form small holes that could accommodate liquid, thereby obtaining a third array template; (7) adding a third metal halide perovskite precursor solution dropwise onto the third array template of step (6), using a spin coater to spin coat the third metal halide perovskite precursor solution to fill the small holes, annealing at 80°C for 10 minutes to form a third metal halide perovskite, then placing it in toluene to remove the polymer layer, heating to volatilize the toluene, and obtaining a three-color perovskite light-emitting microarray; Among them, the solvent of the third metal halide perovskite precursor solution is DMSO, the solute is MAI:PbBr2 with a molar ratio of 1:1, and the third metal halide perovskite precursor solution becomes MAPbIBr2, which emits red light, after annealing.

[0065] The two-color perovskite light-emitting microarrays prepared in Examples 2 to 6 and the three-color perovskite light-emitting microarray in Example 7 are similar to Example 1. The first metal halide perovskite and the second metal halide perovskite or the first metal halide perovskite, the second metal halide perovskite and the third metal halide perovskite present a highly uniform periodic arrangement, and the size of each unit is highly consistent and the boundary is clear, without obvious edge diffusion or crosstalk between adjacent pixels. This indicates that the perovskite light-emitting microarray prepared by the present invention has excellent graphic accuracy and pixel yield.

[0066] Obviously, the above embodiments of the present invention are merely examples for the purpose of clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. Those skilled in the art will appreciate that other variations or modifications can be made based on the above description. It is not necessary and impossible to enumerate all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the claims of the present invention.

Claims

1. A method for preparing a perovskite light-emitting microarray, characterized in that: The following steps are involved: S1. forming a first metal halide perovskite on a substrate to obtain a monochrome perovskite light-emitting microarray; S2. coating a polymer solution on a single-color perovskite light-emitting microarray, annealing to form a polymer layer, and laser etching the polymer layer to form a second array template; S3. adding a second metal halide perovskite precursor solution to the second array template, annealing to form a second metal halide perovskite, and then removing the polymer layer to obtain a perovskite light-emitting microarray; The solvent of the second metal halide perovskite precursor solution and the solvent of the polymer solution are orthogonal solvents.

2. The preparation method according to claim 1, wherein The polymer in the polymer solution is at least one of polystyrene, polymethyl methacrylate or polycarbonate.

3. The preparation method according to claim 1, wherein The solvent of the polymer solution is at least one of toluene, chlorobenzene or dichloromethane.

4. The preparation method according to claim 1, wherein The concentration of the polymer solution is 0.1-1 g / mL.

5. The preparation method according to claim 1, wherein The annealing temperature in each step is 80-100° C., and the annealing time is 10-20 min.

6. The preparation method according to claim 1, wherein The specific process in step S1 is: coating a polymer solution on a substrate, annealing to remove the solvent of the polymer solution to form a polymer layer, and laser etching the polymer layer to form a first array template; adding a first metal halide perovskite precursor solution to a first array template, annealing to form a first metal halide perovskite, and then removing the polymer layer to obtain a single-color perovskite light-emitting microarray; The solvent of the first metal halide perovskite precursor solution and the solvent of the polymer solution are orthogonal solvents.

7. The preparation method according to claim 1, wherein The perovskite light-emitting microarray obtained in step S3 is a dual-color perovskite light-emitting microarray, and the preparation method further includes steps S4 and S5: S4. coating a polymer solution on the dual-color perovskite light-emitting microarray, annealing to form a polymer layer, and laser etching the polymer layer to form a third array template; S5. adding a third metal halide perovskite precursor solution to the third array template, annealing to form the third metal halide perovskite, and then removing the polymer layer to obtain a perovskite light-emitting microarray; The solvent of the third metal halide perovskite precursor solution and the solvent of the polymer solution are orthogonal solvents.

8. The preparation method according to claim 1, wherein The laser etching conditions include: laser etching power of 0.2-30 W, wavelength of 365-1065 nm, and temperature of 0-50° C.

9. A perovskite light-emitting microarray, characterized in that: The compound is prepared by the preparation method according to any one of claims 1 to 8.

10. Use of the perovskite light-emitting microarray according to claim 9 in the preparation of a full-color Micro-LED display.

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