Film forming method and film array preparation method

Abstract

The invention provides a forming method of a thin film and a preparation method of a thin film array, and the forming method of the thin film comprises the following steps: combining a substrate-free flexible thin film with a flexible seal to form a flexible seal thin film; floating the flexible seal film in the volatile liquid infiltrated with the non-planar substrate by using the surface tension of the liquid; the volatile liquid is heated and evaporated, so that the flexible seal film is adsorbed to the non-planar substrate; and the flexible seal layer in the flexible seal film is peeled off, and a formed body with the flexible film adsorbed on the non-planar substrate is obtained.

Description

Technical Field

[0001] The present disclosure relates to the field of coating or other thin film forming technologies, and in particular to a thin film forming method and a thin film array preparation method. Background Art

[0002] With the rapid development of flexible electronic technology, the demand for high-performance thin films in flexible electronic devices such as flexible displays, wearable devices and portable solar cells is increasing. Among the many thin film preparation technologies, atomic layer deposition (ALD) technology is widely used in semiconductors, optoelectronics, energy storage, biomedicine and other fields because of its ability to achieve atomic-level thickness control, high shape retention and excellent uniformity.

[0003] However, ALD technology still has some limitations, which restrict its widespread application in fields such as flexible electronics. First, the ALD process usually requires a high deposition temperature, generally above 300°C. High temperature may cause thermal decomposition or performance degradation of the substrate, thereby affecting the stability and service life of the device, making this method difficult to apply to temperature-sensitive substrates. Secondly, ALD technology is limited in the types of thin film materials that can be deposited. Some materials may be incompatible with the ALD process, or the precursor itself may be unstable, toxic or difficult to handle. This greatly restricts the application of ALD technology when faced with the demand for some special thin film materials. In addition, when faced with complex non-planar substrates, ALD technology also faces problems such as high cost, low deposition rate, and poor scalability.

[0004] Therefore, developing a molding method that can be carried out under low temperature conditions and deposit thin film materials on a wider variety of substrates is of great significance for expanding its application in flexible electronic devices, biomedicine and other fields and meeting the needs of emerging technologies. Summary of the invention

[0005] In view of this, the main purpose of the present disclosure is to provide a method for forming a thin film and a method for preparing a thin film array, in order to at least partially solve at least one of the above-mentioned technical problems.

[0006] To achieve the above purpose, the technical solution of the present invention is as follows:

[0007] In one aspect of the present disclosure, a method for forming a thin film is provided, comprising:

[0008] Combining a flexible film without a substrate with a flexible stamp to form a flexible stamp film;

[0009] By utilizing the surface tension of the liquid, the flexible stamp film is floated in a volatile liquid soaked in a non-planar substrate;

[0010] Heating to evaporate the volatile liquid allows the flexible stamp film to be adsorbed onto the non-planar substrate;

[0011] The flexible stamp layer in the flexible stamp film is peeled off to obtain a molded body with the flexible film adsorbed on the non-planar substrate.

[0012] As a second aspect of the present disclosure, a method for preparing a thin film array is provided, comprising:

[0013] Using the above-mentioned film forming method, a formed body with a flexible film adsorbed on a non-planar substrate is obtained;

[0014] Covering the portion of the flexible film molded body that needs to be retained with a photoresist, and developing the flexible film that is not covered by the photoresist with an etching solution;

[0015] After removing the photoresist, a thin film array is formed on the non-planar substrate surface.

[0016] According to an embodiment of the present disclosure, a method for forming a thin film is provided, in which a prepared substrate-free flexible film is transferred by a flexible stamp, and the flexible film is adsorbed onto a non-planar substrate by utilizing the surface tension of the liquid and the principle of heating evaporation. This method does not require direct high-temperature treatment of the non-planar substrate, thereby effectively avoiding the problem of thermal decomposition or performance degradation of the substrate caused by high temperature in traditional thin film deposition technology. At the same time, with the help of the process of liquid surface tension and heating evaporation, the flexible film can fit tightly to a non-planar substrate with a complex shape, and can achieve efficient and precise forming of the flexible film on a non-planar substrate at room temperature or low temperature (below 100°C). BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a schematic diagram of a method for forming a flexible film in an exemplary embodiment of the present disclosure;

[0018] Figure 2 A schematic diagram of the structure of preparing a flexible film on a planar substrate according to the present disclosure;

[0019] Figure 3 It is a diagram of forming a flexible film on a non-planar substrate in an exemplary embodiment of the present disclosure;

[0020] Figure 4 is a diagram of a thin film array in an exemplary embodiment of the present disclosure;

[0021] Figure 5 is a scanning electron microscope image of a thin film array in an exemplary embodiment of the present disclosure;

[0022] Figure 6 This is a diagram showing the formation of a flexible film on the surface of a cylindrical substrate in Comparative Example 1 of the present disclosure;

[0023] Figure 7 This is a diagram of the flexible film being formed on the surface of a cylindrical substrate in Comparative Example 2 of the present disclosure. DETAILED DESCRIPTION

[0024] In order to make the objectives, technical solutions and advantages of the present disclosure more clearly understood, the present disclosure is further described in detail below in conjunction with specific embodiments.

[0025] The endpoints and any values ​​of the ranges disclosed in this disclosure are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of each range, the endpoint values ​​of each range and the individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, and these numerical ranges should be regarded as specifically disclosed in this disclosure.

[0026] The terms used herein are only for describing specific embodiments and are not intended to limit the present disclosure. The terms "comprise", "include", etc. used herein indicate the existence of the features, steps, operations and / or components, but do not exclude the existence or addition of one or more other features, steps, operations or components.

[0027] In the process of implementing the concept of the present disclosure, it is found that the current film forming method generally requires a high deposition temperature, which makes it difficult to form on a substrate that is not resistant to high temperatures. In addition, for non-planar substrates, the deposition difficulty is further increased. This makes the application of traditional deposition forming technology subject to greater restrictions when facing some special substrate materials (such as non-planar substrate materials that are not resistant to high temperatures).

[0028] In this regard, the present disclosure proposes a method for forming a film, firstly preparing a flexible film on a planar substrate, avoiding high temperature operation directly on a non-planar substrate, and effectively preventing thermal decomposition or performance degradation of the non-planar substrate material caused by high temperature. Then, the flexible film is transferred by a flexible stamp, and the flexible film is adsorbed onto the non-planar substrate by utilizing the surface tension of the liquid and the principle of heating evaporation, so that the flexible film can fit tightly to the non-planar substrate with a complex shape, thereby realizing the forming of the flexible film on the non-planar substrate. In addition, the present disclosure adopts a step-by-step transfer strategy. First, a planar stamp with a small adsorption force and a certain mechanical strength is used to adsorb the flexible film to ensure the integrity and flatness of the flexible film during the transfer process, and then the flexible film is transferred from the planar stamp to a flexible stamp with a large adsorption force and strong flexibility to ensure the flexibility and fit of the film, and finally the flexible film is adsorbed from the flexible stamp to the non-planar substrate so that it can fit perfectly on the complex non-planar substrate. Through this optimized transfer process, the generation of bubbles and wrinkles on the surface of the flexible substrate during the transfer process is effectively reduced, the transfer quality and molding accuracy of the flexible film are significantly improved, and a reliable technical guarantee is provided for the application of high-performance flexible films on complex-shaped substrates.

[0029] According to an embodiment of one aspect of the present disclosure, there is provided a method for forming a thin film, comprising:

[0030] A flexible film without a substrate is combined with a flexible stamp to form a flexible stamp film; the flexible stamp film is floated in a volatile liquid soaked with a non-planar substrate by utilizing the surface tension of the liquid; the volatile liquid is heated and evaporated to make the flexible stamp film adsorbed onto the non-planar substrate; the flexible stamp layer in the flexible stamp film is peeled off to obtain a molded body with the flexible film adsorbed on the non-planar substrate.

[0031] According to an embodiment of the present disclosure, a method for forming a thin film is provided. A flexible film without a substrate is prepared by transferring a flexible stamp, and there is no need to directly perform high-temperature treatment on a non-planar substrate, thereby effectively avoiding the problem of thermal decomposition or performance degradation of the substrate caused by high temperature in traditional thin film deposition technology. The method utilizes the principle of liquid surface tension and heating evaporation. The surface tension of the liquid will cause the liquid to be evenly distributed between the flexible film and the non-planar substrate, filling all gaps, so that the flexible film can fit tightly on the complex surface of the non-planar substrate. During the heating process, the liquid medium gradually evaporates, and the vapor pressure generated during the evaporation process further helps the flexible film to fit the non-planar substrate. As the liquid evaporates, the film is gradually pressed onto the non-planar substrate to form a close contact, and finally the flexible film is adsorbed onto the non-planar substrate. Efficient and precise forming of a flexible film on a non-planar substrate with a complex shape is achieved, while improving the quality and stability of the fit between the flexible film and the non-planar substrate.

[0032] For example, Figure 1 It is a schematic diagram of a method for forming a flexible film in an exemplary embodiment of the present disclosure.

[0033] like Figure 1 As shown, the present invention combines a flexible film without a substrate with a flexible stamp to form a flexible stamp film; utilizes the surface tension of the liquid to float the flexible stamp film in a volatile liquid soaked with a cylindrical three-dimensional structure substrate; heats and evaporates the volatile liquid to adsorb the flexible stamp film onto a non-planar substrate; peels off the flexible stamp layer in the flexible stamp film to obtain a molded body with the flexible film adsorbed on the non-planar substrate. Subsequently, the cylindrical three-dimensional structure substrate is turned over and the above steps are repeated to achieve complete molding of the flexible film on the cylindrical substrate.

[0034] According to an embodiment of the present disclosure, a substrate-free flexible film is combined with a flexible stamp, comprising:

[0035] A sacrificial layer is plated on the surface of a planar substrate, and a flexible film is prepared on the sacrificial layer by a thin film deposition method; a solvent is added to dissolve the sacrificial layer, and a flexible film without a substrate is separated; the surface tension of the liquid is used to adsorb the flexible film onto a planar stamp; the flexible film is adhered to the flexible stamp, and the flexible film is separated from the planar stamp to obtain a flexible film without a substrate, and the flexible film without a substrate is combined with the flexible stamp.

[0036] According to the embodiments of the present disclosure, the introduction of the sacrificial layer can effectively separate the flexible film from the planar substrate, so that after the preparation of the flexible film is completed, it can be separated from the planar substrate without damaging the flexible film by dissolving the sacrificial layer. At the same time, the sacrificial layer provides a flat interface for the growth of the flexible film, which can effectively prevent the formation of strong chemical bonds between the planar substrate and the flexible film, thereby reducing interface defects and contamination, and significantly improving the quality and uniformity of the flexible film. In addition, by combining the flexible film with a planar stamp, the stability and uniformity of the film are further enhanced. Finally, the adhesion of the flexible stamp is used to separate the flexible film from the planar stamp and combine it with the flexible stamp, thereby realizing the efficient preparation and transfer of a substrate-free flexible film.

[0037] For example, Figure 2 It is a schematic diagram of the structure of preparing a flexible film on a planar substrate according to the present disclosure.

[0038] like Figure 2 As shown, the present disclosure plates a sacrificial layer on the surface of a planar substrate, and then uses a thin film deposition method to prepare a target thin film (flexible thin film) on the sacrificial layer.

[0039] According to the embodiments of the present disclosure, the planar substrate includes any one of an oxide substrate, a semiconductor substrate, and a polymer substrate, and different substrate materials can be selected according to the requirements of different application scenarios. The above planar substrate materials all have good high temperature resistance, can meet the requirements of various thin film deposition technologies, and provide a basic guarantee for the high-quality preparation of flexible films.

[0040] The material of the sacrificial layer includes any one of a polymer sacrificial layer, an oxide sacrificial layer, a metal sacrificial layer and a non-metallic sacrificial layer, for example, strontium aluminate (Sr3Al2O6), barium aluminate (Ba3Al2O6), barium strontium aluminate (Sr x Ba 3-x Al2O6) etc. In practical applications, when selecting sacrificial layer materials, choose materials different from the flexible film to ensure that the solvent only dissolves the sacrificial layer materials. By dissolving the sacrificial layer with a solvent, the flexible film can be separated from the flat substrate without damaging it. In addition, the sacrificial layer material can effectively reduce interface defects and contamination while providing a flat deposition interface, thereby significantly improving the quality and uniformity of the flexible film.

[0041] Thin film deposition techniques include electron beam evaporation (e-Beam), atomic layer deposition (ALD), metal organic chemical vapor deposition (MOCVD), and pulsed laser deposition (PLD). According to the requirements of different materials and applications, the appropriate thin film deposition method can be selected to achieve the deposition of flat, uniform, high-quality flexible films.

[0042] The material of the flat stamp includes silicone rubber or carbon-based rubber, such as butyl rubber, isobutyl rubber, polydimethylsiloxane, etc., and a thermal release tape can also be used in actual applications. The flat stamp material has a certain mechanical strength to ensure the integrity of the flexible film. At the same time, there is a small adsorption force between the flat stamp and the flexible film, which facilitates the transfer and separation of the flexible film. The flexible film can be detached from the flat stamp without being damaged, ensuring the quality of the flexible film.

[0043] The temperature for evaporating water is 70~80℃, for example, it can be 70℃, 72℃, 75℃, 78℃, 80℃, etc. The appropriate water evaporation temperature can ensure that the flexible film is evenly adsorbed onto the flat stamp during the heating process, reduce the generation of bubbles and wrinkles between the flexible film and the flat stamp, and avoid performance degradation or damage of the flexible film due to excessive temperature.

[0044] According to an embodiment of the present disclosure, the material of the flexible stamp is an organic material, including polypropylene carbonate (PPC) or polylactic glycolic acid (PLGA), which can ensure that the flexible film is firmly adhered to the stamp surface during the transfer and molding process, and ensure that the flexible film can be stably transferred to a non-planar substrate. The thickness of the flexible stamp is 100μm ~ 1000μm, for example, it can be 100μm, 300μm, 500μm, 700μm, 1000μm, etc. A flexible stamp of appropriate thickness can have sufficient flexibility while ensuring mechanical properties, so that it can be adsorbed onto a non-planar substrate together with the flexible film, avoiding insufficient mechanical strength due to the stamp being too thin or reduced flexibility due to the stamp being too thick.

[0045] According to the embodiments of the present disclosure, the material of the flexible film includes any one of two-dimensional materials, oxides, nitrides, metals and non-metallic elements, and the thickness of the flexible film is 10-100 nm, for example, 10 nm, 30 nm, 50 nm, 70 nm, 100 nm, etc. A flexible film of appropriate thickness can ensure the flexibility of the film, while enabling it to be better adsorbed on complex non-planar substrates of different shapes, ensuring high efficiency and stability in various application scenarios.

[0046] According to an embodiment of the present disclosure, the volatile liquid includes at least one of water or ethanol, and the heating temperature is 70-80°C, for example, 70°C, 72°C, 75°C, 77°C, 80°C, etc. The appropriate heating temperature can make the volatile liquid evaporate evenly at a suitable rate, thereby ensuring that the flexible film remains flat and intact during the transfer and molding process. It effectively avoids the problems of extended preparation time due to slow evaporation, bubble generation and film damage due to fast evaporation, thereby significantly improving the quality and efficiency of film molding.

[0047] According to an embodiment of the present disclosure, a method for peeling off a flexible stamp layer in a flexible stamp film comprises: using an organic solvent to dissolve the flexible stamp layer, wherein the organic solvent is selected from any one of anisole, dimethyl sulfoxide, tetrahydrofuran, and acetone. It can effectively dissolve organic flexible stamp materials (such as polypropylene carbonate or polylactic acid glycolic acid) without damaging the flexible film of inorganic materials. The integrity of the flexible film during the peeling process is ensured, and it is applicable to flexible films of various inorganic materials (such as oxides, metal foils, and other two-dimensional materials).

[0048] According to the embodiments of the present disclosure, the molding method of the present disclosure is applicable to most non-planar substrates containing Gaussian surfaces, and the non-planar substrates include any one of cylindrical substrates, conical substrates, and rectangular substrates. The film molding method of the present disclosure can be widely used in various scenarios requiring high-performance film bonding, whether it is a cylindrical or conical structure with a simple curvature, or a rectangular structure with a complex geometric shape, the flexible film can be tightly attached to the surface of these non-planar substrates, ensuring that the film can achieve high-quality coverage and functionalization on substrates of different shapes, thereby meeting the diverse needs of flexible electronic devices, biomedical sensors, optical devices and other fields for high-performance films.

[0049] For example, Figure 3 FIG. 4 is a diagram of forming a flexible film on a non-planar substrate in an exemplary embodiment of the present disclosure. Figure 3 a is a diagram showing the formation of a flexible film on a nail in an exemplary embodiment of the present disclosure; Figure 3 b is a diagram showing the formation of a flexible film on hair in an exemplary embodiment of the present disclosure; Figure 3 c is a diagram showing the formation of a flexible film on a raised rectangular parallelepiped in an exemplary embodiment of the present disclosure.

[0050] like Figure 3 a~ Figure 3 As shown in c, the film forming method disclosed in the present invention can realize the forming of flexible films on substrate surfaces with various structures.

[0051] According to another embodiment of the present disclosure, there is provided a method for preparing a thin film array, comprising:

[0052] By using the above-mentioned thin film forming method, a molded body with a flexible thin film adsorbed on a non-planar substrate is obtained; the surface of the molded body of the flexible thin film is covered with photoresist, and a mask printed with a preset pattern is covered on the photoresist. After ultraviolet lithography, a developer is used to develop the part not covered by the mask printed with the preset pattern, and the photoresist of the part not covered by the mask printed with the preset pattern is removed to obtain a flexible thin film not covered by the photoresist; an etching solution is used to etch the flexible thin film not covered by the photoresist; after removing the photoresist, a thin film array is formed on the surface of the non-planar substrate.

[0053] According to the embodiments of the present disclosure, the method for preparing a thin film array of the present disclosure can efficiently realize the patterning and arraying of flexible thin films on non-planar substrates. It can not only adapt to non-planar substrates with complex shapes, such as cylindrical, conical, rectangular, etc., but also achieve high-precision patterning. The preparation of flexible thin film arrays is no longer limited to planar substrates, which significantly expands its application range in the fields of flexible electronic devices, sensor arrays, optical devices, etc. At the same time, the method simplifies the traditional process flow, reduces the preparation cost, improves the production efficiency, can meet the application requirements of high-performance thin film arrays on complex structures, and has important practical application value and broad market prospects.

[0054] For example, Figure 4 is a diagram of a thin film array in an exemplary embodiment of the present disclosure, Figure 5 FIG. 4 is a scanning electron microscope image of a thin film array in an exemplary embodiment of the present disclosure.

[0055] like Figure 4 and Figure 5 As shown, the thin film array preparation method disclosed in the present invention can successfully prepare a precise and clear thin film array structure on a substrate.

[0056] According to the embodiments of the present disclosure, in actual application, the photoresist may be, for example, S1813 positive photoresist, the developer may be, for example, a solution of AZ400K: water = 1:4, and the development time may be, for example, 8 to 12 seconds. By selecting different photoresists and etching solutions, and optimizing the development time, the preparation parameters of the thin film array may be flexibly adjusted according to the requirements of different patterns and arrays, thereby achieving a variety of pattern and array designs.

[0057] In order to make the purpose, technical scheme and advantages of the present disclosure more clear, the present disclosure is further described in detail below in conjunction with specific embodiments. Specific techniques or conditions not specified in the embodiments are conventional methods and can be carried out according to the techniques or conditions described in the literature in the art or according to the product instructions.

[0058] Embodiment 1:

[0059] This embodiment provides a film forming method, comprising the following steps S1 to S8:

[0060] Step S1: a strontium aluminate (Sr3Al2O6) sacrificial layer is plated on the surface of a planar substrate, and a flexible film is prepared on the sacrificial layer using a pulsed laser deposition device (PLD);

[0061] Step S2: adding water to dissolve the sacrificial layer, and separating to obtain a flexible film soaked in water;

[0062] Step S3: heating at 70-80° C. to evaporate the water, so that the flexible film is adsorbed onto the polydimethylsiloxane flat stamp;

[0063] Step S4: using a polypropylene carbonate flexible stamp to adhere the flexible film, so that the flexible film is separated from the polydimethylsiloxane flat stamp to obtain a flexible film without a substrate, and combining the flexible film without a substrate with the polypropylene carbonate flexible stamp to form a flexible stamp film.

[0064] Step S5: placing the columnar substrate in a beaker, adding ethanol so that the liquid level exceeds the columnar substrate, placing the flexible stamp film on the ethanol liquid level, and floating the flexible film face down in the ethanol soaked with the columnar substrate;

[0065] Step S6: heating at 70-80° C. to evaporate the ethanol, and waiting for the ethanol liquid to completely evaporate before the flexible film is adsorbed on the column;

[0066] Step S7: using anisole to dissolve the polypropylene carbonate flexible stamp;

[0067] Step S8: Turn over the cylindrical substrate and repeat the above steps S1 to S7.

[0068] In Example 1 of the present disclosure, a molded body having a flexible film adsorbed on a cylindrical substrate is obtained.

[0069] Comparative Example 1

[0070] Comparative Example 1 of the present disclosure provides a film forming method, comprising the following steps S1 to S7:

[0071] Step S1: a strontium aluminate (Sr3Al2O6) sacrificial layer is plated on the surface of a planar substrate, and a flexible film is prepared on the sacrificial layer using a pulsed laser deposition device (PLD);

[0072] Step S2: adding water to dissolve the sacrificial layer, and separating to obtain a flexible film soaked in water;

[0073] Step S3: heating at 70-80° C. to evaporate the water, so that the flexible film is adsorbed onto the polydimethylsiloxane flat stamp;

[0074] Step S4: placing the columnar substrate in a beaker, adding ethanol so that the liquid level exceeds the columnar substrate, placing the polydimethylsiloxane flat stamp adsorbed with the flexible film on the ethanol liquid surface, and floating the flexible film face downward in the ethanol soaked with the columnar substrate;

[0075] Step S6: heating and evaporating ethanol at 70-80° C., and after all the ethanol liquid evaporates, the flexible film is separated from the polydimethylsiloxane flat stamp and adsorbed on the columnar body;

[0076] Step S7: Turn over the cylindrical substrate and repeat the above steps S1 to S6.

[0077] Figure 6 This is a diagram of the flexible film being formed on the surface of a cylindrical substrate in Comparative Example 1 of the present disclosure.

[0078] like Figure 6 As shown, the flexible film of comparative example 1 of the present disclosure cannot be adsorbed and formed on the cylindrical substrate. Since the polydimethylsiloxane flat stamp itself has high elasticity and low flexibility, it will not deform with the shape of the non-planar substrate, and the adsorption and transfer of the flexible film cannot be achieved.

[0079] Comparative Example 2

[0080] Comparative Example 1 of the present disclosure provides a film forming method, comprising the following steps S1 to S7:

[0081] Step S1: a strontium aluminate (Sr3Al2O6) sacrificial layer is plated on the surface of a planar substrate, and a flexible film is prepared on the sacrificial layer using a pulsed laser deposition device (PLD);

[0082] Step S2: adding water to dissolve the sacrificial layer, and separating to obtain a flexible film soaked in water;

[0083] Step S3: heating at 70-80° C. to evaporate the water, so that the flexible film is adsorbed onto the polypropylene carbonate flexible stamp to form a flexible stamp film;

[0084] Step S4: placing the columnar substrate in a beaker, adding ethanol so that the liquid level exceeds the columnar substrate, placing the flexible stamp film on the ethanol liquid level, and floating the flexible film face down in the ethanol soaked with the columnar substrate;

[0085] Step S5: heating at 70-80° C. to evaporate ethanol, and waiting for the ethanol liquid to completely evaporate before the flexible film is adsorbed on the column;

[0086] Step S6: using anisole to dissolve the polypropylene carbonate flexible stamp;

[0087] Step S7: Turn over the cylindrical substrate and repeat the above steps S1 to S6.

[0088] Figure 7 This is a diagram of the flexible film being formed on the surface of a cylindrical substrate in Comparative Example 2 of the present disclosure.

[0089] like Figure 7As shown, bubbles and wrinkles exist on the surface of the molded body with the flexible film adsorbed on the cylindrical substrate in Comparative Example 2 of the present disclosure. This is because the flexible film is relatively flexible and the flexible stamp has a strong adsorption to it, so bubbles and wrinkles are easily generated when the flexible film is adsorbed on the surface of the flexible stamp. When the flexible film is further adsorbed on the cylindrical substrate, these bubbles and wrinkles cannot be eliminated, resulting in the inability to form a flat structure.

[0090] The specific embodiments described above further illustrate the purpose, technical solutions and beneficial effects of the present disclosure. It should be understood that the above description is only a specific embodiment of the present disclosure and is not intended to limit the present disclosure. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present disclosure should be included in the protection scope of the present disclosure.

Claims

1. A film forming method, characterized in that: The molding method comprises: Combining a flexible film without a substrate with a flexible stamp to form a flexible stamp film; Utilizing the surface tension of the liquid, the flexible stamp film is floated in a volatile liquid soaked in a non-planar substrate; heating and evaporating the volatile liquid so that the flexible stamp film is adsorbed onto the non-planar substrate; The flexible stamp layer in the flexible stamp film is peeled off to obtain a molded body with the flexible film adsorbed on the non-planar substrate.

2. The molding method according to claim 1, characterized in that: The volatile liquid includes at least one of water or ethanol; The heating temperature is 70-80°C.

3. The molding method according to claim 1, characterized in that: The material of the flexible stamp includes polypropylene carbonate or polylactic acid glycolic acid; The thickness of the flexible stamp is 100 μm to 1000 μm; The material of the flexible film includes any one of two-dimensional materials, oxides, nitrides, metals and non-metallic elements; The thickness of the flexible film is 0.1-100 nm.

4. The molding method according to claim 1, characterized in that: The method of combining a substrate-free flexible film with a flexible stamp comprises: Plating a sacrificial layer on the surface of a planar substrate, and preparing the flexible film on the sacrificial layer by a thin film deposition method; dissolving the sacrificial layer to separate and obtain the flexible film; Using surface tension to make the flexible film adsorb onto the flat stamp; The flexible film is adhered to the flexible film by using a flexible stamp, so that the flexible film is separated from the planar stamp to obtain a flexible film without a substrate, and the flexible film without a substrate is combined with the flexible stamp.

5. The molding method according to claim 4, characterized in that: The sacrificial layer includes any one of a polymer sacrificial layer, an oxide sacrificial layer, a metal element sacrificial layer and a non-metal element sacrificial layer; The material of the planar stamp includes any one of silicone rubber and carbon-based rubber.

6. The molding method according to claim 4, characterized in that: The planar substrate includes any one of an oxide substrate, a semiconductor substrate, and a polymer substrate; The thin film deposition method includes any one of electron beam evaporation, atomic layer deposition, metal organic chemical vapor deposition, and pulsed laser deposition.

7. The molding method according to claim 1, characterized in that: The method for stripping the flexible stamp layer in the flexible stamp film comprises: dissolving the flexible stamp layer by using an organic solvent, wherein the organic solvent is selected from any one of anisole, dimethyl sulfoxide, tetrahydrofuran and acetone.

8. The molding method according to claim 1, further comprising: The non-planar substrate includes any one of a cylindrical substrate, a conical substrate, and a rectangular substrate.

9. A method for preparing a thin film array, characterized in that: The preparation method comprises: Using the thin film forming method according to any one of claims 1 to 8, a formed body having a flexible film adsorbed on the non-planar substrate is obtained; The surface of the molded body of the flexible film is covered with photoresist, and a mask printed with a preset pattern is covered on the photoresist. After ultraviolet lithography, a developer is used to develop the portion not covered by the mask printed with the preset pattern, and the photoresist of the portion not covered by the mask printed with the preset pattern is removed to obtain a flexible film not covered by the photoresist; Etching the flexible film not covered by the photoresist using an etching solution; After removing the photoresist, a thin film array is formed on the surface of the non-planar substrate.

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