Patterned halogen perovskite thin films, methods of making and applications thereof

Abstract

The application provides a patterned halogen perovskite film and a preparation method and application thereof, and the method comprises the following steps: (1) forming a photoresist film on a halogen perovskite film; (2) exposing the photoresist film obtained in the step (1); (3) developing the photoresist film obtained in the step (2); (4) placing the halogen perovskite film formed with the photoresist film obtained in the step (3) in a hydrogen halide acid solution for etching; and (5) placing the halogen perovskite film with the photoresist film remaining obtained in the step (4) in a mixture of halogen perovskite and an organic solvent for stripping, drying, and obtaining a patterned halogen perovskite film. Thus, the preparation method is compatible with modern microelectronic processes, and the quality and properties of the halogen perovskite film are basically unchanged before and after stripping, and the halogen perovskite film has a wide application prospect in the fields of photoelectric imaging arrays, display arrays, photoelectric logic array devices and the like.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of semiconductor micro-nano processing, in particular to a patterned halogen perovskite film and a preparation method and application thereof. BACKGROUND

[0002] Currently, the preparation methods of dense perovskite films mainly include spin coating, blade coating, etc., wherein the quality of the film obtained by spin coating can be further improved by using an anti-solvent, specifically, a perovskite solution is first prepared and then dropped on a substrate for spin coating, and an anti-solvent such as toluene, isopropyl alcohol, etc. is dropped during the spin coating process to induce rapid crystallization of the perovskite, thereby obtaining a dense perovskite film. However, the patterning of perovskite materials is still in the research stage and cannot be practically applied. For example, the patterning of methylammonium lead iodine perovskite has certain limitations in the method, which cannot be completely applied to different perovskites, and the preparation method itself is relatively complex and cannot be compatible with modern microelectronic silicon processes.

[0003] Therefore, the preparation method of the patterned halogen perovskite film still needs to be further improved. SUMMARY

[0004] The present application aims to at least solve one of the technical problems in the related art. To this end, one object of the present application is to provide a halogen perovskite film and a preparation method and application thereof, which can be compatible with modern microelectronic processes, and the quality and properties of the halogen perovskite film remain basically unchanged before and after stripping, and has a wide application prospect in the fields of photoelectric imaging arrays, display arrays, and photoelectric logic array devices.

[0005] In one aspect of the present application, a method for patterning a halogen perovskite film is provided, which comprises: (1) forming a photoresist film on a halogen perovskite film; (2) exposing the photoresist film obtained in step (1); (3) developing the photoresist film obtained in step (2); (4) etching the halogen perovskite film formed with the photoresist film obtained in step (3) in a hydrogen halide acid solution; (5) stripping the halogen perovskite film remaining with the photoresist film obtained in step (4) in a mixture of halogen perovskite and organic solvent, and drying to obtain a patterned halogen perovskite film. Thus, the preparation method can be compatible with modern microelectronic processes, and the quality and properties of the halogen perovskite film remain basically unchanged before and after stripping, and has a wide application prospect in the fields of photoelectric imaging arrays, display arrays, and photoelectric logic array devices.

[0006] According to some embodiments of the present application, the method further comprises: configuring a halogen perovskite precursor solution, depositing the halogen perovskite precursor solution onto a substrate, and annealing to form the halogen perovskite film.

[0007] According to some embodiments of the present application, the anti-solvent is added dropwise during the deposition process, and the anti-solvent is selected from at least one of ethanol and isopropanol. Thereby, the film formation of halogen perovskite is promoted.

[0008] According to some embodiments of the present application, the mass-volume ratio of the halogen perovskite and the organic solvent in the mixture of the halogen perovskite and the organic solvent is 0.1 mg / mL to 10 mg / mL. Thereby, the degradation of the halogen perovskite is inhibited during the de-bonding process, and the halogen perovskite film is prevented from being damaged during the de-bonding process.

[0009] According to some embodiments of the present application, the mixture of the halogen perovskite and the organic solvent is a colloid.

[0010] According to some embodiments of the present application, the particle size of the colloid is 10 nm to 1000 nm.

[0011] According to some embodiments of the present application, the de-bonding time is 3 s to 20 s.

[0012] According to some embodiments of the present application, the organic solvent is selected from at least one of acetone, ethanol, isopropanol, N,N-dimethylformamide, dimethyl sulfoxide, N-methyl pyrrolidone, and tetrahydrofuran.

[0013] According to some embodiments of the present application, in step (5), the halogen perovskite is the same as the halogen perovskite in the halogen perovskite film in step (1).

[0014] According to some embodiments of the present application, the hydrogen halide acid includes at least one of HF, HCl, HBr, and HI. Thereby, the halogen perovskite film is etched.

[0015] According to some embodiments of the present application, the halogen perovskite in step (1) is selected from any one of ABX3 and A2CDX6, wherein A is CH3NH3 + or Cs + , B is Pb 2+ or Sn 2+ , C is Ag + , D is Bi 3+ , and X is any one of Cl - , Br - , and I - .

[0016] According to some embodiments of the present application, the solvent in step (1) includes at least one of N,N-dimethylformamide, dimethyl sulfoxide, and γ-butyrolactone.

[0017] According to some embodiments of the present application, the concentration of the halogen perovskite precursor solution is 0.1-1.5 mol / L.

[0018] In another aspect of the present application, a patterned halogen perovskite thin film prepared by the aforementioned method is provided. Thus, the halogen perovskite thin film has all the features and advantages of the halogen perovskite thin film prepared by the aforementioned method, which are not repeated here. In general, the halogen perovskite thin film has at least the advantages of being convenient in film quality and property before and after de-bonding, and can be widely used in photoelectric imaging arrays, display arrays, photoelectric logic array devices, etc.

[0019] In yet another aspect of the present application, the use of the patterned halogen perovskite thin film prepared by the aforementioned method in photoelectric imaging arrays, display arrays, photoelectric logic array devices, etc. is provided. BRIEF DESCRIPTION OF DRAWINGS

[0020] The above and / or additional aspects and advantages of the present application will become apparent and be readily appreciated from the following description, including the appended drawings, of embodiments of the present application.

[0021] Figure 1 A flowchart showing the preparation method of the patterned halogen perovskite thin film in an embodiment of the present application is shown;

[0022] Figure 2 A patterned halogen perovskite thin film prepared in Example 1 of the present application is shown;

[0023] Figure 3 A patterned halogen perovskite thin film prepared in Comparative Example 1 is shown;

[0024] Figure 4 A UV-Vis absorption spectrum of the halogen perovskite thin film prepared in Example 1 of the present application is shown;

[0025] Figure 5 An optical spectrum absorption graph of the halogen perovskite thin film prepared in Example 1 of the present application is shown;

[0026] Figure 6 An optical band gap spectrum of the halogen perovskite thin film prepared in Example 1 of the present application is shown. DETAILED DESCRIPTION

[0027] Embodiments of the present application are described in detail below. The embodiments described below are exemplary only, and are not to be construed as limiting the present application. Unless otherwise defined, technical or scientific terms used in the embodiments have the same meaning as commonly understood by one of ordinary skill in the art to which the present application pertains. Unless otherwise required by context, singular terms shall include pluralities and vice versa. Generally, the nomenclature used herein and the laboratory procedures are in accordance with standard practices of the chemical and biological arts. The nomenclature used herein follows the rules of the International Union of Pure and Applied Chemistry (IUPAC). The practice of the present application will employ, unless otherwise indicated, conventional methods of chemistry, biochemistry, molecular biology, microbiology, cell biology, and immunology, all within the skill of the art.

[0028] In one aspect of the present application, a method for patterning a halogen perovskite film is provided, which comprises: (1) forming a photoresist film on the halogen perovskite film; (2) exposing the photoresist film obtained in step (1); (3) developing the photoresist film obtained in step (2); (4) etching the perovskite film with the photoresist film formed thereon obtained in step (3) in a hydrogen halide acid solution; (5) removing the photoresist film from the perovskite film obtained in step (4) in a mixture of halogen perovskite and organic solvent, drying to obtain a patterned halogen perovskite film. Thus, the preparation method is compatible with modern microelectronic processes, and the quality and properties of the halogen perovskite film remain unchanged before and after removal of the photoresist film, which has broad application prospects in the fields of optoelectronic imaging arrays, display arrays, and optoelectronic logic array devices.

[0029] For the convenience of understanding, the principle of the method capable of achieving the above beneficial effects is described in detail as follows:

[0030] Currently, acetone is used for removing the photoresist film during the preparation of perovskite films, which damages the perovskite film (see Figure 3 ). In the present application, saturated or supersaturated halogen perovskite is added to the organic solvent, so that even if the organic solvent contacts the perovskite film during the removal of the photoresist film, the degradation of the halogen perovskite can be inhibited due to the presence of the saturated or supersaturated halogen perovskite in the organic solvent, thereby protecting the perovskite film. As a result, the quality and properties of the perovskite film remain unchanged before and after removal of the photoresist film, which has broad application prospects in the fields of optoelectronic imaging arrays, display arrays, and optoelectronic logic array devices. Moreover, the method is compatible with modern microelectronic processes, which is further conducive to industrialization.

[0031] Hereinafter, each step of the method is described in detail according to an embodiment of the present application, which is described with reference to Figure 1 , and the method comprises:

[0032] S100: forming a photoresist film on the halogen perovskite film

[0033] In this step, a photoresist film is formed on the halogen perovskite film. According to some embodiments of the present application, the photoresist film can be formed on the halogen perovskite film by spin coating, blade coating, and spraying, etc., and preferably, the photoresist film is formed by spin coating. According to some specific embodiments of the present application, the type of photoresist is not particularly limited, which can be positive photoresist or negative photoresist, and can be freely selected by those skilled in the art.

[0034] According to some embodiments of the present application, the halogen perovskite film can be prepared by the following method:

[0035] S110: configuring a halogen perovskite precursor solution, depositing the halogen perovskite precursor solution onto a substrate, and annealing to form a halogen perovskite thin film

[0036] In this step, the perovskite precursor compounds are weighed according to the proportion and dissolved in a polar solvent, according to some embodiments of the present application, the polar solvent includes at least one of N, N-dimethylformamide, dimethyl sulfoxide, gamma-butyrolactone. It should be particularly pointed out here that after the perovskite precursor is dissolved in the organic solvent, the concentration of the solution is 0.1 mol / L-1.5 mol / L, thereby obtaining a dense thin film.

[0037] According to some embodiments of the present application, the halogen perovskite precursor solution can be deposited on the substrate by spin coating, blade coating and spraying, etc. as long as a uniform thin film can be formed.

[0038] According to some embodiments of the present application, an anti-solvent can be added dropwise during the spin coating process to promote the formation of halogen perovskite film by rapidly evaporating the solvent. The type of anti-solvent is not particularly limited, for example, it can be selected from at least one of ethanol, isopropanol.

[0039] According to some specific embodiments of the present application, an annealing process can also be performed during the film formation process, and the annealing temperature is 180-380°C. At this time, the vacancies, anti-sites and other defects on the surface and inside of the perovskite are repaired. When the annealing temperature is in the above range, the perovskite structure is more stable, and the quality of the prepared crystal is better. The annealing time is 3-30 min, and when the annealing time is in the above range, the vacancies and anti-site defects inside and on the surface of the perovskite can be effectively repaired.

[0040] According to some embodiments of the present application, the halogen perovskite is selected from any one of ABX3 and A2CDX6, wherein A is CH3NH3 + or Cs + , B is Pb 2+ or Sn 2+ , C is Ag + , D is Bi 3+ , and X is any one of Cl - , Br - , I - . Thus, the material system has good carrier lifetime and carrier mobility.

[0041] S200: exposure

[0042] In this step, the photoresist thin film obtained in the above step is placed under a mask for exposure. The exposure method is not particularly limited, preferably, by ultraviolet exposure, the part of the photoresist irradiated by light is denatured, and is washed out or retained during development; the exposure time is 10-60 s.

[0043] S300: developing

[0044] In this step, the exposed photoresist film is developed. According to some embodiments of the present application, the type of developing solution is not particularly limited. When the photoresist is a positive photoresist, a positive developing solution can be used so that the exposed part is dissolved in the developing solution to form a predetermined pattern. When the photoresist is a negative photoresist, a negative developing solution can be used so that the unexposed part is dissolved in the developing solution to form a predetermined pattern.

[0045] S400: etching

[0046] In this step, the perovskite film exposed at the position where the developed photoresist film is dissolved is etched using a hydrogen halide solution. Thus, the hydrogen halide can coordinate with the metal ions in the halogen perovskite and etch the halogen perovskite by virtue of its acidity. In addition, the hydrogen halide can prevent the halogen perovskite from hydrolyzing. According to some embodiments of the present application, the hydrogen halide includes at least one of HF, HCl, HBr, and HI, and the etching time is 3 s to 30 s so that the halogen perovskite is completely etched but not excessively etched.

[0047] S500: removing photoresist

[0048] In this step, the film with residual photoresist is placed in a halogen perovskite and organic solvent mixture to remove the photoresist. According to some embodiments of the present application, the halogen perovskite is the same as the halogen perovskite in the halogen perovskite film in step S100. According to some embodiments of the present application, the mass / volume ratio of the halogen perovskite to the organic solvent in the halogen perovskite and organic solvent mixture is 0.1 mg / mL to 10 mg / mL. Thus, the organic solvent contains saturated or supersaturated halogen perovskite, which prevents the perovskite film from degrading and the organic solvent from damaging the perovskite film during the removal of the photoresist, thereby ensuring that the quality and performance of the perovskite film before and after the removal of the photoresist do not change substantially. It should be particularly noted that the halogen perovskite can form a solution, a suspension, or the like in the organic solvent. Preferably, the halogen perovskite and organic solvent mixture is a colloid. Thus, according to the dissolution-precipitation balance of the colloid system, the perovskite component ions in the liquid phase of the mixture are kept in a saturated state. The inventors have found that if the concentration of the halogen perovskite in the organic solvent does not reach the saturation concentration, the perovskite film will dissolve.

[0049] According to some embodiments of the present application, when the mixture of halogen perovskite and organic solvent is a colloid, the particle size of the formed colloid is 10 nm to 1000 nm. When the particle size of the colloid is within the above range, the dissolution of the perovskite film can be prevented, and meanwhile, there is no obvious residue of the colloidal particles. The inventors have found that when the particle size of the colloid is too small, the saturation of ions in the system cannot be guaranteed, and the perovskite film can be dissolved; when the particle size of the colloid is too large, the colloidal particles are easy to be left on the surface of the perovskite film, which can change the morphology of the film.

[0050] According to some embodiments of the present application, the organic solvent is not particularly limited, and can be selected by those skilled in the art as needed, for example, can be selected from at least one of acetone, ethanol, isopropanol, N,N-dimethylformamide, dimethyl sulfoxide, N-methyl pyrrolidone and tetrahydrofuran. According to some embodiments of the present application, the stripping time is not particularly limited, as long as the remaining photoresist can be completely removed, for example, the stripping time can be 3 to 20 s, thereby ensuring the complete removal of the photoresist.

[0051] In another aspect of the present application, a patterned halogen perovskite film is provided, which is prepared by the above method. Thus, the halogen perovskite film has all the features and advantages of the halogen perovskite film prepared by the above method, which will not be repeated here. In general, at least the film quality and properties before and after stripping are not affected, and can be widely used in the fields of optoelectronic imaging array, display array, optoelectronic logic array device, etc.

[0052] In yet another aspect of the present application, the use of the patterned halogen perovskite film in optoelectronic imaging array, display array, optoelectronic logic array device is provided.

[0053] Example 1

[0054] 1. A DMSO solution of halogen perovskite precursors CsBr, AgBr and BiBr3 is spin-coated on a silicon wafer at a spin speed of 700 rpm for 10 s, and then the spin speed is adjusted to 2000 rpm for 1 min;

[0055] When the spin speed is 2000 rpm for about 20 s, an anti-solvent isopropanol is added dropwise to promote crystallization and film formation, and then the film is annealed at 280°C for about 5 min to obtain a uniform and dense halogen perovskite film on the silicon wafer;

[0056] 2. Then AZ601 photoresist positive glue is spin-coated on the perovskite film at a spin speed of 700 RPM for 7 s, and then the spin speed is adjusted to 3000 RPM for 40 s to obtain a photoresist film;

[0057] 3. The photoresist film is exposed to a mask for 40 s using a photoetching machine in an ultraviolet contact exposure mode;

[0058] 4. Then immerse in positive photoresist developer for about 20 s to obtain the pattern of photoresist, and rinse off the residual developer;

[0059] 5. Etch using aqueous hydrobromic acid for about 5 s;

[0060] 6. Place 10 mg of Cs2AgBiBr6 in an acetone solution, dissolve the filter membrane to obtain a saturated Cs2AgBiBr6-acetone mixture, use the Cs2AgBiBr6-acetone mixture to remove the residual photoresist, rinse and dry to obtain a patterned halogen perovskite thin film.

[0061] Example 2

[0062] 1. Use the spin coating method to spin coat a DMSO solution of halogen perovskite precursors CsI and BiI3 on a silicon wafer, with spin coating parameters of 700 rpm for 10 s, and adjust the spin coating speed to 2000 rpm for 1 min;

[0063] When the spin coating speed is 2000 rpm for about 20 s, drop the anti-solvent ethanol to promote crystallization and film formation, and then anneal at 280°C for about 5 min to obtain a uniform and dense perovskite thin film on the silicon wafer;

[0064] 2. Then spin coat 3000PY photoresist negative resist on the halogen perovskite thin film, with a spin coating speed of 700 RPM for 7 s, and then adjust the speed to 3000 RPM for 40 s to obtain a photoresist thin film;

[0065] 3. Expose for 40 s using a photoetching machine and a mask, with an ultraviolet contact exposure method;

[0066] 4. Then immerse in negative photoresist developer for about 20 s to obtain the pattern of photoresist, and rinse off the residual developer;

[0067] 5. Etch using aqueous hydrobromic acid for about 5 s;

[0068] 6. Place 10 mg of Cs3Bi2I9 in an acetone solution, dissolve the filter membrane to obtain a saturated Cs3Bi2I9-acetone mixture, use the Cs3Bi2I9-acetone mixture to remove the residual photoresist, rinse and dry to obtain a patterned halogen perovskite thin film.

[0069] Comparative Example 1

[0070] 1. Use the spin coating method to spin coat a DMSO solution of halogen perovskite precursors CsBr, AgBr and BiBr3 on a silicon wafer, with spin coating parameters of 700 rpm for 10 s, and adjust the spin coating speed to 2000 rpm for 1 min;

[0071] When the spin coating speed is 2000 rpm and about 20 seconds, the antisolvent ethanol is added dropwise to promote crystallization and film formation. Then, the film is annealed at 280℃ for about 5 minutes to obtain a uniform and dense perovskite film on the silicon wafer.

[0072] 2. Then spin-coat AZ601 photoresist onto the halide perovskite film. Spin-coat at 700 RPM for 7 seconds, then adjust the speed to 3000 RPM for 40 seconds to obtain the photoresist film.

[0073] 3. Expose for 40 seconds using a lithography machine and photomask; the exposure method is ultraviolet contact exposure.

[0074] 4. Then soak in positive photoresist developer (as a comparative example of Example 1) for about 20 seconds to obtain the photoresist pattern, and rinse off the residual developer.

[0075] 5. Use hydrobromic acid aqueous solution for etching, the etching time is about 5 seconds;

[0076] 6. Use acetone to remove residual photoresist, rinse and dry to obtain a patterned halide perovskite film.

[0077] Performance testing

[0078] Figure 2 , Figure 3 These are images from a scanning electron microscope test. The equipment used was a scanning electron microscope from FEI Corporation, and the imaging method was secondary electron imaging. Figure 4 The image shows a UV-Vis absorption spectrum, measured using a Hach SOE-151 UV spectrophotometer (solid-state).

[0079] Figure 2 and Figure 3 The strip-shaped structures in the image represent perovskite. As can be seen from the image, perovskite removed directly with acetone was partially dissolved, while perovskite removed using Cs2AgBiBr6-acetone colloid remained very dense, showing no damage. Figure 4 As can be seen, the absorption spectrum of perovskite degummed directly with acetone is significantly weaker than that of perovskite degummed using Cs2AgBiBr6-acetone colloid, indicating that perovskite degummed directly with acetone suffers severe degradation; from Figure 5 and Figure 6 It can be seen that the optical absorption and optical band gap of the perovskite material remain almost unchanged before and after patterning.

[0080] In the description of the specification, the description of the terms "one embodiment", "some embodiments", "an example", "a specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are contained in at least one embodiment or example of the present application. In the specification, the illustrative description of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any suitable manner in any one or more embodiments or examples. In addition, the person skilled in the art can combine and combine the different embodiments or examples described in the specification and the features of the different embodiments or examples without contradiction.

[0081] Although the embodiments of the present application have been shown and described above, it is understood that the above-described embodiments are exemplary and are not to be construed as limiting the present application, and those skilled in the art can make changes, modifications, replacements and variations to the above-described embodiments within the scope of the present application.

Claims

1. A method for patterning halide perovskite thin films, characterized in that, include: (1) Prepare a haloperovskite precursor solution, deposit the haloperovskite precursor solution onto a substrate, anneal it to form a haloperovskite thin film, and form a photoresist film on the haloperovskite thin film. (2) Expose the photoresist film obtained in step (1); (3) Develop the photoresist film obtained in step (2); (4) The halide perovskite film with the photoresist film obtained in step (3) is placed in a hydrogen halide acid solution for etching; (5) The halide perovskite film with the photoresist film remaining obtained in step (4) is placed in a mixture of halide perovskite and organic solvent to remove the photoresist and dry it to obtain a patterned halide perovskite film. The mass-to-volume ratio of the haloperovskite to the organic solvent in the mixture of haloperovskite and organic solvent is 0.1 mg / mL to 10 mg / mL; The mixture of the halide perovskite and the organic solvent is a colloid; The particle size of the colloid is 10 nm to 1000 nm; Glue removal time: 3~20s; The concentration of the halide perovskite precursor solution is 0.1 mol / L to 1.5 mol / L.

2. The method according to claim 1, characterized in that, An antisolvent is added dropwise during the deposition process, the antisolvent being selected from at least one of ethanol and isopropanol.

3. The method according to claim 1, characterized in that, In step (5), the organic solvent is selected from at least one of acetone, ethanol, isopropanol, N,N-dimethylformamide, dimethyl sulfoxide, N-methylpyrrolidone and tetrahydrofuran; In step (5), the halo perovskite is the same as the halo perovskite in the halo perovskite film in step (1).

4. The method according to claim 1, characterized in that, The hydrogen halide includes at least one of HF, HCl, HBr, and HI.

5. The method according to claim 1, characterized in that, The halide perovskite in the halide perovskite film described in step (1) is selected from either ABX3 or A2CDX6, wherein A is CH3NH3. + or Cs + B is Pb 2+ or Sn 2+ C is Ag + D is Bi 3+ X is Cl - ,Br - I - Any one of them.

6. The method according to claim 1, characterized in that, The solvent in the halide perovskite precursor solution includes at least one of N,N-dimethylformamide, dimethyl sulfoxide, and γ-butyrolactone.

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