Method for refining metal grid nodes

Abstract

The invention relates to the technical field of metal grid electrodes, in particular to a method for refining metal grid nodes, which comprises the following steps of: S1, refining the nodes of a photomask; s2, plating copper on the metal grid electrode through an electroplating method; s3, coating the metal grid electrode with a photoresist film; s4, exposing and developing the coated metal grid electrode by using the refined photomask to obtain a required pattern; and S5, removing redundant copper and the photoresist film through etching and demolding to obtain a required circuit. According to the method for refining the nodes of the metal grid, the nodes of the photomask are refined in advance, and after exposure and development, a photoresist film can be correspondingly refined at the nodes, so that enough space is formed for node thickening caused by copper ion mass transfer blocking at the nodes, and the node thickness is reduced; according to the method, the metal grid with normal nodes can be obtained, so that the problems of influence on light transmittance and the like can be avoided.

Description

Technical Field

[0001] The invention relates to the technical field of metal grid electrodes, and in particular to a method for refining metal grid nodes. Background Art

[0002] In the field of capacitive touch screens, metal grids have received widespread attention due to their excellent performance and mature preparation process. The technology of preparing metal grid transparent electrode materials using yellow light subtractive process is becoming more and more mature. However, in the wet preparation process, due to the influence of mass transfer factors, fluid dynamics, etc., the metal grid nodes are relatively large, which is not conducive to the transmittance of the metal grid transparent electrode. In order to refine the nodes, it is necessary to start from the preparation principle of the metal grid yellow light process. The key steps that affect the metal grid nodes are the exposure stage and the etching stage. In this patent, we mainly discuss the method of optimizing the nodes in the exposure stage. Usually we use a mask to expose the photoresist in a pattern, and the photoresist at the exposure is retained during the development process to act as a protective layer for the metal grid lines.

[0003] In the prior art, such as Figure 1 As shown in the figure, if the line width of the mask slit remains consistent, the line width of the photoresist will remain consistent after development. During the etching and side etching processes, the copper ion concentration at the nodes is relatively high, which affects the ion mass transfer and solution exchange during the etching process, resulting in larger nodes. In the process of metal grid preparation, larger nodes will affect the transmittance and other problems, which need to be improved. Summary of the invention

[0004] The object of the present invention is to provide a method for metal mesh node refinement to solve the problems raised in the above background technology.

[0005] To achieve the above object, the present invention provides the following technical solution: a method for metal grid node refinement, comprising the following steps:

[0006] S1: refine the mask nodes;

[0007] S2: Copper is plated on the metal grid electrode by electroplating;

[0008] S3: Covering the metal grid electrode with a photoresist film;

[0009] S4: using the refined photomask to expose and develop the metal grid electrode after lamination to obtain the required pattern;

[0010] S5: Remove excess copper and photoresist film through etching and stripping to obtain the required circuit.

[0011] Preferably, in S1, thinning the mask nodes specifically refers to adding synapses at the nodes so as to reduce the side length of the inscribed square at the nodes.

[0012] Preferably, the width of the mask slit is 10-30 microns.

[0013] Preferably, the side length of the inscribed square at the node is 20-80% of the mask slit width.

[0014] Preferably, the starting width of the synaptic fold line ranges from 10 to 50 microns.

[0015] Compared with the prior art, the present invention has the following beneficial effects:

[0016] The present invention proposes a method for refining metal grid nodes. The nodes of the mask are refined in advance. After exposure and development, the photoresist film is also refined accordingly at the nodes, thereby leaving enough space for the nodes to become thicker due to the obstruction of copper ion mass transfer at the nodes. Through this method, a metal grid with normal nodes can be obtained, thereby avoiding problems such as affecting transmittance. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 The figure is a process flow chart of the prior art.

[0018] Figure 2 It is a process flow chart of the present invention.

[0019] Figure 3 It is an enlarged view of the node of the mask of the present invention.

[0020] In the figure: a is the width of the mask slit, b is the side length of the inscribed square at the node, and c is the starting width of the synaptic fold line. DETAILED DESCRIPTION

[0021] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0022] See also Figures 1 to 3 The present invention provides a technical solution: a method for refining metal mesh nodes, comprising the following steps:

[0023] S1: refine the mask nodes;

[0024] S2: Copper is plated on the metal grid electrode by electroplating;

[0025] S3: Covering the metal grid electrode with a photoresist film;

[0026] S4: using the refined photomask to expose and develop the metal grid electrode after lamination to obtain the required pattern;

[0027] S5: Remove excess copper and photoresist film through etching and stripping to obtain the required circuit.

[0028] In S1, thinning the mask nodes specifically refers to adding synapses at the nodes so as to reduce the side length of the inscribed square at the nodes.

[0029] The width of the mask slit is 10-30 microns.

[0030] The side length of the inscribed square at the node is 20-80% of the slit width of the mask.

[0031] The width of the synaptic fold line starting point ranges from 10 to 50 μm.

[0032] Specific embodiment 1: first, the nodes of the mask are refined so that the slit width is 20 microns, the side length of the inscribed square at the node is 10 microns, and the starting width of the synaptic fold line is 10 microns. Copper is plated on the metal grid electrode by electroplating, and then the metal grid electrode is covered with a photoresist film. The refined mask is used to expose and develop the metal grid electrode after coating to obtain the required pattern, and the excess copper and photoresist film are removed by etching and demolding to obtain the required node-refined circuit.

[0033] Specific embodiment 2: first, refine the nodes of the mask so that the slit width is 30 microns, the side length of the inscribed square at the node is 15 microns, and the starting width of the synaptic fold line is 20 microns. Copper is plated on the metal grid electrode by electroplating, and then the metal grid electrode is covered with a photoresist film. The refined mask is used to expose and develop the metal grid electrode after coating to obtain the required pattern, and the excess copper and photoresist film are removed by etching and demolding to obtain the required node-refined circuit.

[0034] In this aspect, the nodes of the mask are thinned in advance, and after exposure and development, the photoresist film is also thinned accordingly at the nodes, thereby leaving enough space for the nodes to become thicker due to the obstruction of copper ion mass transfer at the nodes. This method can obtain a metal grid with normal nodes, thereby avoiding problems such as affecting transmittance.

[0035] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for metal mesh node refinement, characterized in that: The following steps are included: S1: refine the mask nodes; S2: Copper is plated on the metal grid electrode by electroplating; S3: Covering the metal grid electrode with a photoresist film; S4: using the refined photomask to expose and develop the metal grid electrode after lamination to obtain the required pattern; S5: Remove excess copper and photoresist film through etching and stripping to obtain the required circuit.

2. A method for metal mesh node refinement according to claim 1, characterized in that: In S1, thinning the mask nodes specifically refers to adding synapses at the nodes so as to reduce the side length of the inscribed square at the nodes.

3. A method for metal mesh node refinement according to claim 1, characterized in that: The width of the slit of the photomask is 10-30 microns.

4. The method for metal mesh node refinement according to claim 1, characterized in that: The side length of the inscribed square at the node is 20-80% of the slit width of the mask.

5. A method for metal mesh node refinement according to claim 2, characterized in that: The starting width of the synaptic fold line ranges from 10 to 50 microns.

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