Template for repeatedly preparing flexible transparent electrode with metal pattern as well as preparation method and application of template

Abstract

The invention provides a template for repeatedly preparing a flexible transparent electrode with a metal pattern as well as a preparation method and application of the template. The preparation method comprises the following steps: (1) providing a base material; (2) coating photoresist on one surface of the base material, and exposing and developing to obtain the base material of which the surface is provided with a photoetching pattern; (3) etching the surface of the base material obtained in the step (2) to obtain the base material with a groove in the surface; and (4) depositing a metal material on the surface of the base material obtained in the step (3), and removing the photoresist and redundant metal to obtain the template. The template prepared through the preparation method is smooth in surface, high in pattern precision and capable of being repeatedly used; the template is used for preparing the flexible transparent electrode with the metal pattern, it can be guaranteed that the flexible transparent electrode has high precision and good conductivity and light transmission, meanwhile, the production cost can be reduced, and the production efficiency can be improved.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of metal mesh flexible transparent electrode, and particularly relates to a template for repeatedly preparing a flexible transparent electrode with a metal pattern, a preparation method thereof and application. BACKGROUND

[0002] The metal mesh flexible transparent electrode is composed of a flexible substrate and a metal mesh pattern, and is a functional material with high conductivity, excellent flexibility and certain light transmittance. It solves the problem of brittleness and poor flexibility of traditional conductive materials (such as ITO), while maintaining the conductivity close to that of metal, and can be widely used in flexible electronic devices, photovoltaic fields, smart wearable devices and other fields.

[0003] There are various methods for preparing the metal mesh flexible transparent electrode, such as photolithography, nanoimprint, screen printing and the like. However, the photolithography method usually involves multiple steps such as photolithography, etching, sputtering, laser scribing, film forming and the like, resulting in high cost and low production efficiency. The metal mesh prepared by the nanoimprint method, screen printing method and the like cannot be fine, and the conductivity and light transmittance of the transparent electrode prepared thereby are difficult to improve.

[0004] For example, CN114283994A discloses a preparation method of an embedded metal mesh flexible electrode film, which comprises: preparing a metal mesh on a glass substrate by photolithography; coating a polymer on the metal mesh and curing it into a film, and then peeling off the glass substrate to obtain an embedded metal mesh flexible electrode film. The method needs photolithography for each preparation, and uses a metal deposition process to prepare the metal pattern, which is complex.

[0005] For another example, CN107610814A discloses a method for preparing a transparent electrode based on an ultrathin metal mesh, which comprises the following steps: (1) surface modification of a flexible transparent substrate; (2) forming a mask plate on the surface of the flexible transparent substrate by photolithography or colloid printing; (3) depositing a metal layer with a thickness of 1-10 nm in the gap of the mask plate; (4) removing the mask plate to obtain a transparent electrode based on an ultrathin metal mesh. However, the transparent electrode prepared by the method has obvious undulations on the surface and poor pattern accuracy.

[0006] Therefore, it is an urgent problem in the field to develop a method for preparing a metal mesh flexible transparent electrode which can ensure high pattern accuracy, has good conductivity and light transmittance, and can also reduce production cost and improve production efficiency. SUMMARY

[0007] In view of the deficiencies of the prior art, the present application aims to provide a template for repeatedly preparing a flexible transparent electrode with a metal pattern, a preparation method and application thereof; the template prepared by the preparation method has a smooth surface, high pattern accuracy and can be repeatedly used; the template is used to prepare the flexible transparent electrode with the metal pattern, which can not only ensure that the flexible transparent electrode has high accuracy, good conductivity and light transmittance, but also can reduce production cost and improve production efficiency.

[0008] To achieve the above-mentioned purpose, the present application adopts the following technical solutions:

[0009] In a first aspect, the present application provides a preparation method of a template for repeatedly preparing a flexible transparent electrode with a metal pattern, which comprises the following steps:

[0010] (1) providing a substrate;

[0011] (2) coating a photoresist on one surface of the substrate, and obtaining a substrate with a photoetching pattern on the surface after exposure and development;

[0012] (3) etching the surface of the substrate obtained in step (2) to obtain a substrate with a groove on the surface;

[0013] (4) depositing a metal material on the surface of the substrate obtained in step (3), removing the photoresist and excess metal to obtain the template.

[0014] In the present application, a specific process is adopted, i.e. photoetching, etching and deposition, to obtain a template with a smooth surface and high pattern accuracy, which can accurately control the duty cycle of the metal pattern on the entire transparent electrode, and thus obtain a transparent electrode with good conductivity and light transmittance; and the template can be repeatedly used, which can be used to prepare a metal mesh transparent electrode without the need for photoetching and other steps, thereby simplifying the preparation process of the metal mesh transparent electrode, accelerating the preparation progress, reducing the production cost and improving the production efficiency.

[0015] Preferably, the substrate in step (1) is selected from a substrate with a smooth surface.

[0016] In the present application, the use of a substrate with a smooth surface is beneficial to obtain a template with a smooth surface, and thus obtain a flexible transparent electrode with a metal pattern with better performance (such as conductivity, light transmittance, etc.).

[0017] Preferably, the substrate in step (1) comprises at least one of a silicon oxide substrate, glass and a composite substrate.

[0018] Preferably, the composite substrate comprises a conductive layer and an insulating layer arranged in sequence, and more preferably, the composite substrate is a heavily doped conductive silicon wafer with an oxide layer on the surface.

[0019] In the present application, when the substrate is selected from a composite substrate formed by a conductive layer and an insulating layer, a photoresist is coated on the surface of the insulating layer.

[0020] In the present application, the surface material of the substrate is more preferably silicon oxide. Silicon oxide is resistant to high temperature and corrosion, has a low coefficient of thermal expansion, good electrical insulation, and a precise and perfect etching process. Moreover, silicon oxide glass is common, and a heavy-doped silicon wafer with a surface of silicon oxide is a preferred composite substrate, which has a mature preparation process and is easy to obtain.

[0021] Preferably, the substrate in step (1) comprises a cleaned substrate.

[0022] Preferably, the cleaning agent for cleaning comprises at least one of water, acetone, and isopropyl alcohol; more preferably, water, acetone, and isopropyl alcohol are used in sequence for cleaning.

[0023] In the present application, dust and oil stains on the surface of the substrate are removed by cleaning to avoid affecting subsequent operations.

[0024] Preferably, the coating method in step (2) comprises at least one of blade coating, spraying, and spin coating.

[0025] Preferably, the thickness of the coating in step (2) is 3-10 µm, for example, it can be 4 µm, 5 µm, 6 µm, 7 µm, 8 µm, 9 µm, etc.

[0026] In the present application, when the area of the template is ≤10 cm×10 cm, the spin coating method is used, and when the area of the template is >10 cm×10 cm, the blade coating and / or spraying method is used.

[0027] Preferably, the photoresist in step (2) comprises a positive photoresist and / or a negative photoresist.

[0028] Preferably, the exposure time in step (2) is 30-90 s, for example, it can be 35 s, 40 s, 45 s, 50 s, 55 s, 60 s, 70 s, 80 s, 85 s, etc.; and the developing method comprises soaking in a developing solution for 10-60 s, for example, it can be 12 s, 14 s, 16 s, 18 s, 20 s, 25 s, 30 s, 35 s, 40 s, 45 s, 50 s, 55 s, etc.

[0029] Preferably, the photoetching pattern in step (2) comprises at least one of a continuous honeycomb pattern, a grid pattern, and a discontinuous dot matrix pattern.

[0030] In the present application, the photoetching pattern is not limited to the above-mentioned patterns, but can also be selected from other patterns, and a suitable photoetching pattern can be formed on the surface of the substrate according to actual needs.

[0031] Preferably, the dot matrix pattern is composed of dot matrix units, and the shape of the dot matrix units comprises regular polygons and irregular shapes.

[0032] Preferably, the photoetching pattern is selected from a discontinuous dot matrix pattern, and the substrate is selected from a composite substrate, i.e., a substrate that is conductive at the bottom layer but insulating and flat at the surface layer.

[0033] Preferably, the etching method of step (3) comprises dry etching and / or wet etching.

[0034] In the present application, the etching of step (3) is performed on the surface of the substrate provided with the photoetching pattern obtained in step (2).

[0035] Preferably, the dry etching method comprises at least one of active oxygen etching (AOE) and reactive ion etching (RIE).

[0036] In the present application, the speed of the active oxygen etching is 1000-3000 A / min, for example, it can be 1200 A / min, 1400 A / min, 1600 A / min, 1800 A / min, 2000 A / min, 2200 A / min, 2400 A / min, 2500 A / min, 2600 A / min, 2800 A / min, etc.; and the time is 0.5-5 min, for example, it can be 1 min, 2 min, 3 min, 4 min, 5 min, etc.

[0037] In the present application, the etching gas used in the reactive ion etching comprises CHF3, and / or a mixed gas of CF4 and H2.

[0038] Preferably, the wet etching comprises etching using an etching solution; and the etching solution comprises hydrofluoric acid.

[0039] Preferably, the etching solution for the wet etching is hydrofluoric acid, the mass concentration of the hydrofluoric acid is 30-70%, the temperature for the wet etching is room temperature, and the time for the wet etching is 1-20 min, for example, it can be 2 min, 4 min, 6 min, 8 min, 10 min, 12 min, 14 min, 16 min, 18 min, etc.

[0040] Preferably, the etching depth is 100-1000 nm, for example, it can be 150 nm, 200 nm, 250 nm, 300 nm, 350 nm, 400 nm, 450 nm, 500 nm, 550 nm, 600 nm, 650 nm, 700 nm, 750 nm, 800 nm, 850 nm, 900 nm, 950 nm, etc.

[0041] In the present application, the etching depth is in a certain range, which ensures the conductivity required for electroplating while improving the precision of the pattern; if the etching depth is too small, it cannot embed enough conductive metal material, affecting the subsequent electroplating; if the etching depth is too large, the etching difficulty increases, and the difficulty of embedding metal also increases, affecting the accuracy of the pattern.

[0042] Preferably, the method of step (4) includes a magnetron sputtering method.

[0043] In the present application, the power of the magnetron sputtering is 100-300 W, for example, it can be 120 W, 150 W, 180 W, 200 W, 220 W, 250 W, 280 W, etc.; the time is 1-60 min, for example, it can be 20 min, 25 min, 30 min, 35 min, 40 min, 45 min, 50 min, 55 min, etc.

[0044] Preferably, the metal material of step (4) includes at least one of chromium (Cr), copper (Cu), silver (Ag), and titanium (Ti), and more preferably chromium.

[0045] In the present application, the metal material is preferably selected from chromium, which has high hardness, good corrosion resistance, and strong bonding force with various materials, which is conducive to the repeated use of the template.

[0046] Preferably, the thickness of the deposited metal material of step (4) is the same as the etching depth.

[0047] In the present application, the thickness of the deposited metal material is the same as the etching depth, that is, the metal material completely fills the groove obtained by etching, which is conducive to obtaining a template with a smooth surface.

[0048] In the present application, the method of removing the photoresist and excess metal includes cleaning with an organic solvent; the organic solvent can be a solvent that can dissolve the photoresist, such as acetone, isopropyl alcohol, etc.

[0049] In a second aspect, the present application provides a template for repeatedly preparing a flexible transparent electrode with a metal pattern, which is prepared by the preparation method of the first aspect; the template includes a substrate with a groove on the surface and a metal layer filled in the groove.

[0050] In this invention, the thickness of the metal layer is 100~1000 nm, for example, it can be 150 nm, 200 nm, 250 nm, 300 nm, 350 nm, 400 nm, 450 nm, 500 nm, 550 nm, 600 nm, 650 nm, 700 nm, 750 nm, 800 nm, 850 nm, 900 nm, 950 nm, etc.

[0051] Thirdly, the present invention provides a method for preparing a flexible transparent electrode with a metallic pattern, the method comprising the following steps:

[0052] (S1) Electroplating a metal material onto the template surface as described in the second aspect to obtain a template with a metal pattern on the surface that is the same as the template pattern;

[0053] (S2) Apply polymer material to the surface of the template with metal pattern obtained in step (S1), form a film, peel off, and obtain the flexible transparent electrode with metal pattern.

[0054] In this invention, the template is used to prepare a flexible transparent electrode with a metal pattern. Only two steps are required: electroplating and film formation. This yields a flexible transparent electrode with high pattern precision, good conductivity, and good light transmittance, simplifying the production process and reducing production costs. Furthermore, after preparation, the template only needs simple cleaning before film formation can be performed again, eliminating the need for repeated photolithography, magnetron sputtering, and other steps. This enables continuous, large-scale production of flexible transparent electrodes with metal patterns. Moreover, the electroplating process forms a metal pattern on the template surface, making the conductive metal denser and better ensuring overall conductivity.

[0055] Preferably, the metallic material in step (S1) includes at least one of nickel (Ni), copper (Cu), silver (Ag), chromium (Cr), and zinc (Zn).

[0056] In this invention, the electroplated metal material can be selected according to actual needs. For example, if better corrosion resistance is required, Ni and Cr can be selected; if better conductivity is required, Cu and Ag can be selected; or a combination of multiple materials can be selected to meet different performance requirements.

[0057] Preferably, the thickness of the metal pattern in step (S1) is 1~30μm, for example, it can be 2μm, 3μm, 4μm, 5μm, 6μm, 7μm, 8μm, 9μm, 10μm, 11μm, 12μm, 13μm, 14μm, 16μm, 18μm, 20μm, 22μm, 24μm, 26μm, 28μm, etc.

[0058] In this invention, the appropriate current is selected during electroplating according to the type of metal material to be electroplated; for example, the current density used for nickel electroplating is 3~5A / dm², and the current density used for copper electroplating is 2~8A / dm². The electroplating time is determined by the thickness of the electroplated material (i.e., the thickness of the metal pattern).

[0059] In this invention, by controlling the thickness of the metal pattern within a specific range, it is beneficial to obtain a flexible transparent electrode with better conductivity and higher precision; if the thickness of the metal pattern is too small, the conductivity will be poor; if the thickness is too large, the precision will decrease.

[0060] Preferably, the method for setting the polymer material in step (S2) includes at least one of chemical vapor deposition and coating.

[0061] Preferably, the polymer material in step (S2) includes at least one of parylene and polyimide.

[0062] In this invention, when the polymer material is selected from parylene, a chemical vapor deposition method is used to form a film; when the polymer material is selected from polyimide, a coating method is used to form a film, in which a polyimide solution is coated on the template surface obtained in step (S1), and then thermosetting to form a film.

[0063] In this invention, the chemical vapor deposition rate is 1~10 A / s, for example, 2 A / s, 4 A / s, 6 A / s, 8 A / s, etc.; the time is 5~15h, for example, 6h, 7h, 8h, 9h, 10h, 11h, 12h, 14h, etc.

[0064] In this invention, the thickness of the thin film formed by the polymer material is 1~30µm, for example, it can be 2µm, 4µm, 6µm, 8µm, 10µm, 12µm, 14µm, 16µm, 18µm, 20µm, 22µm, 24µm, 26µm, 28µm, etc.

[0065] In this invention, the selection of polymer materials and film-forming methods can be made according to actual needs (actual application scenarios); the polymer materials are not limited to those mentioned above, and other types of polymer materials can be selected according to actual needs.

[0066] In this invention, the peeling is achieved by physically pulling the film directly off the template surface to obtain a flexible transparent electrode with an embedded metal pattern.

[0067] Fourthly, the present invention provides a flexible transparent electrode with a metal pattern, wherein the flexible transparent electrode with the metal pattern is prepared by the preparation method described in the third aspect.

[0068] In this invention, the flexible transparent electrode with a metal pattern includes a flexible substrate and a metal material embedded on the surface of the flexible substrate.

[0069] Fifthly, the present invention provides an application of the flexible transparent electrode with a metallic pattern described in the fourth aspect in flexible electronic devices, photovoltaics, and smart wearable devices.

[0070] The numerical range described in this invention includes not only the point values ​​listed above, but also any point values ​​within the numerical ranges not listed above. Due to space limitations and for the sake of brevity, this invention will not exhaustively list all the specific point values ​​included in the range.

[0071] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0072] The present invention provides a method for preparing a template for reproducibly fabricating flexible transparent electrodes with metallic patterns. This method employs a specific process, namely photolithography, etching, and deposition, to produce a template with a smooth surface and high pattern precision. It allows for precise control of the duty cycle of the metallic pattern across the entire transparent electrode, resulting in a transparent electrode with both good conductivity and light transmittance. Furthermore, the template is reusable; it can be used to prepare metal mesh transparent electrodes without requiring further photolithography steps, simplifying the fabrication process, accelerating the fabrication progress, reducing production costs, and improving production efficiency. Attached Figure Description

[0073] Figure 1 This is a flowchart illustrating the method for preparing a template for repeatedly fabricating a flexible transparent electrode with a metallic pattern, as provided by the present invention.

[0074] The process includes: 1-Providing a substrate; 2-Coating photoresist; 3-Exposure and development; 4-Etching; 5-Depositing metal material; 6-Removing photoresist and excess metal material.

[0075] Figure 2 A flowchart illustrating the method for fabricating a flexible transparent electrode with a metallic pattern provided by this invention.

[0076] Wherein, 1- Electroplating of metal material on the template surface; 2- Film formation; 3- Peeling.

[0077] Figure 3 This is a schematic diagram of the metal pattern on the surface of the flexible transparent electrode with a metal pattern obtained in Embodiment 1 of the present invention.

[0078] Figure 4 This is a schematic diagram of the metal pattern on the surface of the flexible transparent electrode with a metal pattern obtained in Embodiment 2 of the present invention.

[0079] Figure 5This is a schematic diagram of the metal pattern on the surface of the flexible transparent electrode with a metal pattern obtained in Embodiment 3 of the present invention. Detailed Implementation

[0080] The technical solution of the present invention will be further illustrated below through specific embodiments. Those skilled in the art should understand that the embodiments described are merely illustrative of the present invention and should not be construed as limiting the invention in any way.

[0081] All materials used in this invention can be purchased commercially or prepared using conventional methods. Unless otherwise specified, the materials used in this invention are as follows.

[0082] Photoresist: Anzhi AZ6130 imported photoresist, Shenzhen Ruige Ruisi Technology Co., Ltd.

[0083] Parylene: Parker Nanotechnology (Suzhou) Co., Ltd.

[0084] Polyimide: Dongguan Zhanyang Polymer Materials Co., Ltd.

[0085] Example 1

[0086] This embodiment provides a method for preparing a template for repeatedly fabricating flexible transparent electrodes with metallic patterns, the flowchart of which is shown below. Figure 1 As shown, the specific steps include:

[0087] (1) Provide a substrate, wherein the substrate is a silicon oxide glass substrate with a glass thickness of 1.1 mm; the substrate is sequentially cleaned with water, acetone and isopropanol for 10 min each, and dried at 60°C to obtain the cleaned substrate.

[0088] (2) Coating the substrate surface with photoresist to a thickness of 5µm, exposing for 60s, and immersing in AZ300MIF developer at 23°C for 60s to obtain a substrate with a photolithographic pattern on the surface.

[0089] (3) The substrate obtained in step (2) is etched with photoresist to obtain a substrate with grooves on the surface; wherein the etching method is active oxygen etching, and the etching is performed at a speed of 2500A / min for 2min; the etching depth is 500nm.

[0090] (4) Magnetron sputtering of chromium metal onto the substrate surface obtained in step (3) at a power of 200W for 25 minutes, and then immersing it in acetone for ultrasonic cleaning to remove photoresist and excess metal, thereby obtaining the template; the template includes a groove with a depth of 500nm on its surface and a chromium metal layer filled in the groove, the thickness of the chromium metal layer being 500nm.

[0091] This embodiment provides a method for fabricating a flexible transparent electrode with a metallic pattern, the flowchart of which is shown below. Figure 2 As shown, the specific steps include:

[0092] (S1) Electroplating of copper metal onto the surface of the template, with a current of 0.2A and a time of 40min, yields a template with a metal pattern of 8μm thickness on its surface.

[0093] (S2) A parylene film (10µm thick) is prepared on the surface of the template with the metal pattern by chemical vapor deposition. The specific process of chemical vapor deposition is as follows: deposition is carried out at a rate of 4A / s for 10h; then the film is peeled off from the template surface by physical pulling to obtain the flexible transparent electrode with the metal pattern; the flexible transparent electrode with the metal pattern includes a parylene substrate and a metal pattern (8µm thick, grid pattern, pattern shape as shown) embedded on the surface of the parylene substrate. Figure 3 (As shown).

[0094] The template in this embodiment can be reused after it is prepared. The subsequent preparation of flexible transparent electrodes with metal patterns no longer requires repeated tedious operations such as photolithography, etching, and magnetron sputtering. The metal mesh pattern on the template will not be damaged or deformed in subsequent operations, which simplifies the process of preparing flexible transparent electrodes with metal patterns and reduces the manufacturing cost.

[0095] Example 2

[0096] This embodiment provides a method for preparing a template for reproducibly fabricating a flexible transparent electrode with a metallic pattern, specifically including the following steps:

[0097] (1) Provide a substrate, wherein the substrate is a heavily doped conductive silicon wafer substrate with a 300nm oxide layer on the surface and a thickness of 625µm; the substrate is sequentially cleaned with water, acetone and isopropanol for 10min each, and dried at 60℃ to obtain the cleaned substrate.

[0098] (2) Coating the substrate surface with photoresist to a thickness of 5µm, exposing for 60s, and immersing in AZ300MIF developer at 23°C for 60s to obtain a substrate with a photolithographic pattern on the surface.

[0099] (3) The substrate obtained in step (2) is etched with photoresist to obtain a substrate with grooves on the surface; wherein the etching method includes reactive ion etching, the corrosion gas is CHF3, and the etching depth is 300nm.

[0100] (4) Magnetron sputtering of chromium metal onto the substrate surface obtained in step (3) at a power of 200W for 15 minutes, followed by cleaning with acetone to remove photoresist and excess metal, to obtain the template; the template includes a groove with a depth of 300nm on its surface and a chromium metal layer filled in the groove, the thickness of the chromium metal layer being 300nm.

[0101] This embodiment provides a method for preparing a flexible transparent electrode with a metallic pattern, specifically including the following steps:

[0102] (S1) Electroplating of copper metal onto the surface of the template, with a current of 0.2A and a time of 20min, yields a template with a metal pattern of 4μm thickness on its surface.

[0103] (S2) A polyimide film (5µm thick) is prepared on the surface of the template with the metal pattern by a coating method. The specific method includes: coating a polyimide solution (20% solid content, DMAC solvent) onto the template surface, and curing it sequentially at 100℃ for 0.5h, 150℃ for 0.5h, and 280℃ for 2h; then peeling the film off the template surface by physical pulling to obtain the flexible transparent electrode with the metal pattern; the flexible transparent electrode with the metal pattern includes a polyimide substrate and a metal pattern (4µm thick, continuous honeycomb pattern, pattern shape as shown) embedded on the surface of the polyimide substrate. Figure 4 (As shown).

[0104] The template in this embodiment can be reused after it is prepared. The subsequent preparation of flexible transparent electrodes with metal patterns no longer requires repeated tedious operations such as photolithography, etching, and magnetron sputtering. The metal mesh pattern on the template will not be damaged or deformed in subsequent operations, which simplifies the process of preparing flexible transparent electrodes with metal patterns and reduces the manufacturing cost.

[0105] Example 3

[0106] This embodiment provides a method for preparing a template for reproducibly fabricating a flexible transparent electrode with a metallic pattern, specifically including the following steps:

[0107] (1) Provide a substrate, wherein the substrate is a heavily doped conductive silicon wafer substrate with a 150nm oxide layer on the surface and a thickness of 625µm; the substrate is sequentially cleaned with water, acetone and isopropanol for 10min each, and dried at 60℃ to obtain the cleaned substrate.

[0108] (2) Coating the substrate surface with photoresist to a thickness of 5µm, exposing for 60s, and immersing in AZ300MIF developer at 23°C for 60s to obtain a substrate with a photolithographic pattern on the surface.

[0109] (3) The substrate obtained in step (2) is etched with photoresist to obtain a substrate with grooves on the surface; wherein the etching method is to use hydrofluoric acid for etching, and immerse in 40% HF solution at room temperature for 3 minutes; the etching depth is 150 nm.

[0110] (4) Magnetron sputtering of chromium metal onto the substrate surface obtained in step (3) at a power of 200W for 9 minutes, followed by cleaning with acetone to remove photoresist and excess metal, to obtain the template; the template includes a groove with a depth of 150nm on its surface and a chromium metal layer filled in the groove, the thickness of the chromium metal layer being 150nm.

[0111] This embodiment provides a method for preparing a flexible transparent electrode with a metallic pattern, specifically including the following steps:

[0112] (S1) Electroplating of copper metal onto the surface of the template, with a current of 0.2A and a time of 1h, yields a template with a metal pattern of 13μm thickness on the surface.

[0113] (S2) A polyimide film (15µm thick) is prepared on the surface of the template with the metal pattern by a coating method, the specific method being the same as in Example 2; then the film is peeled off from the template surface by physical pulling to obtain the flexible transparent electrode with the metal pattern; the flexible transparent electrode with the metal pattern includes a polyimide substrate and a metal pattern (13µm thick, discontinuous dot matrix pattern, composed of multiple square dot matrix units, the pattern shape is as follows) embedded on the surface of the polyimide substrate. Figure 5 (As shown).

[0114] The template in this example can be reused after it is prepared. Subsequent preparation of flexible transparent electrodes with metal patterns no longer requires repeated tedious operations such as photolithography, etching, and magnetron sputtering. The metal mesh pattern on the template will not be damaged or deformed in subsequent operations, simplifying the process of preparing flexible transparent electrodes with metal patterns and reducing manufacturing costs.

[0115] Example 4

[0116] This embodiment provides a method for preparing a template for reproducible flexible transparent electrode with metal pattern. The difference between this method and Example 1 is that step (4) involves magnetron sputtering of metallic copper, while the other steps and process parameters are the same as in Example 1.

[0117] This embodiment provides a method for preparing a flexible transparent electrode with a metallic pattern, and the specific steps are the same as in Embodiment 1.

[0118] The template in this embodiment can be reused after preparation. However, copper is a relatively soft material. After being reused 5 times, the metal pattern will be partially deformed and incomplete, which will affect the accuracy of the subsequent preparation of flexible transparent electrodes with metal patterns. As the number of repetitions increases, the deformation and incompleteness of the metal pattern will increase until the template is damaged.

[0119] Example 5

[0120] This embodiment provides a method for preparing a template for repeatedly preparing a flexible transparent electrode with a metal pattern. The difference between this method and that of Embodiment 1 is that the etching depth in step (3) is 50 nm, while the other steps and process parameters are the same as those in Embodiment 1.

[0121] This embodiment provides a method for preparing a flexible transparent electrode with a metallic pattern, and the specific steps are the same as in Embodiment 1.

[0122] In this embodiment, the template metal pattern is too thin. Due to insufficient conductivity during the electroplating process, the quality of the electroplated metal mesh is poor, which affects the conductivity of the flexible transparent electrode.

[0123] Example 6

[0124] This embodiment provides a method for preparing a template for reproducible flexible transparent electrode with a metal pattern. The difference between this method and that of Embodiment 1 is that the etching depth in step (3) is 1200 nm, while the other steps and process parameters are the same as those in Embodiment 1.

[0125] This embodiment provides a method for preparing a flexible transparent electrode with a metallic pattern, and the specific steps are the same as in Embodiment 1.

[0126] In this embodiment, the etching depth is too deep, which affects the accuracy of the template metal pattern. The 1200nm metal conductive layer sputtered is difficult to remove excess metal afterward, affecting the surface flatness of the template. Consequently, the accuracy of the prepared flexible transparent electrode with metal pattern decreases and the surface undulation increases.

[0127] In summary, the method for preparing a template for reproducibly fabricating flexible transparent electrodes with metallic patterns provided by this invention employs a specific process, namely photolithography, etching, and deposition, to produce a template with a smooth surface and high pattern precision. This allows for precise control of the duty cycle of the metallic pattern across the entire transparent electrode, resulting in a transparent electrode with both good conductivity and light transmittance. Furthermore, the template is reusable; it can be used to prepare metal mesh transparent electrodes without requiring further photolithography steps, simplifying the fabrication process, accelerating the fabrication progress, reducing production costs, and improving production efficiency.

[0128] The applicant declares that the above description is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention fall within the protection and disclosure scope of the present invention.

Claims

1. A method for preparing a template for reproducibly fabricating flexible transparent electrodes with metallic patterns, characterized in that, The preparation method includes the following steps: (1) Provide a substrate; (2) Photoresist is coated on one surface of the substrate, and after exposure and development, a substrate with a photolithographic pattern on the surface is obtained; (3) Etch the surface of the substrate obtained in step (2) to obtain a substrate with grooves on the surface; (4) Deposit metal material on the substrate surface obtained in step (3), remove photoresist and excess metal, and obtain the template.

2. The preparation method according to claim 1, characterized in that, The substrate mentioned in step (1) is selected from a substrate with a flat surface; Preferably, the substrate in step (1) includes at least one of silicon oxide substrate, glass, and composite substrate; Preferably, the composite substrate includes a conductive layer and an insulating layer disposed sequentially; more preferably, the composite substrate is a heavily doped conductive silicon wafer with an oxide layer disposed on its surface. Preferably, the substrate in step (1) includes a cleaned substrate; Preferably, the cleaning agent includes at least one of water, acetone, and isopropanol; more preferably, water, acetone, and isopropanol are used sequentially for cleaning.

3. The preparation method according to claim 1 or 2, characterized in that, The coating method in step (2) includes at least one of scraping, spraying, and spin coating; Preferably, the coating thickness in step (2) is 3~10µm; Preferably, the photoresist in step (2) includes positive photoresist and / or negative photoresist; Preferably, the exposure time in step (2) is 30-90 seconds, and the development method includes immersion in the developing solution for 10-60 seconds; Preferably, the photolithographic pattern in step (2) includes at least one of a continuous honeycomb pattern, a grid pattern, and a discontinuous dot matrix pattern; Preferably, the dot pattern is composed of dot matrix units, and the shape of the dot matrix units includes regular polygons and / or irregular shapes; Preferably, the photolithographic pattern is selected from discontinuous dot matrix patterns, and the substrate is selected from composite substrates.

4. The preparation method according to any one of claims 1 to 3, characterized in that, The etching method described in step (3) includes dry etching and / or wet etching; Preferably, the dry etching method includes at least one of reactive oxygen species etching and reactive ion etching; Preferably, the wet etching includes etching with an etching solution; the etching solution includes hydrofluoric acid; Preferably, the etching solution used in the wet etching is hydrofluoric acid, the mass concentration of the hydrofluoric acid is 30-70%, the wet etching temperature is room temperature, and the wet etching time is 1-20 min. Preferably, the etching depth is 100~1000nm.

5. The preparation method according to any one of claims 1 to 4, characterized in that, The deposition method in step (4) includes magnetron sputtering; Preferably, the metallic material in step (4) includes at least one of chromium, copper, silver, and titanium, more preferably chromium; Preferably, the thickness of the deposited metal material in step (4) is the same as the depth of the etching.

6. A template for reproducibly fabricating flexible transparent electrodes with metallic patterns, characterized in that, The template is prepared using the preparation method described in any one of claims 1 to 5; The template includes a substrate with grooves on its surface and a metal layer filled in the grooves.

7. A method for preparing a flexible transparent electrode with a metallic pattern, characterized in that, The preparation method includes the following steps: (S1) Electroplating a metal material on the template surface as described in claim 6 to obtain a template with a metal pattern on the surface that is the same as the template pattern; (S2) Apply polymer material to the surface of the template with metal pattern obtained in step (S1), form a film, peel off, and obtain the flexible transparent electrode with metal pattern.

8. The preparation method according to claim 7, characterized in that, The metallic material mentioned in step (S1) includes at least one of nickel, copper, silver, chromium, and zinc; Preferably, the thickness of the metal pattern in step (S1) is 1~30μm; Preferably, the method for setting the polymer material in step (S2) includes at least one of chemical vapor deposition and coating. Preferably, the polymer material in step (S2) includes at least one of parylene and polyimide.

9. A flexible transparent electrode with a metallic pattern, characterized in that, The flexible transparent electrode with the metallic pattern is prepared using the preparation method described in claim 7 or 8.

10. The application of a flexible transparent electrode with a metallic pattern according to claim 9 in flexible electronic devices, photovoltaics, and smart wearable devices.

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