Multi-shape micron-sized metal grid structure based on printing shielding and electroplating thickening and preparation method thereof

Abstract

The invention discloses a multi-shape micron-sized metal grid structure based on printing shielding and electroplating thickening and a preparation method of the multi-shape micron-sized metal grid structure, and belongs to the technical field of micro-nano manufacturing. The aperture of an opening of the metal grid is 30-70 microns, the line width is 15-30 microns, the height is 5-15 microns, the metal grid is made of copper, nickel or an alloy thereof, grid units are circular, square, triangular, hexagonal or a combination thereof, and the performance can be optimized through periodic or non-periodic arrangement. The ratio of the line width to the opening of the grid is 1: 2-1: 4, the balance light transmittance is larger than or equal to 85%, the sheet resistance is smaller than or equal to 10 omega / square, and the performance and the precision of the grid are optimized through parameter collaboration; printing shielding is adopted to replace traditional photoetching, and the manufacturing cost is reduced by more than 30%; by optimizing printing shielding and electroplating processes and combining multi-shape structure innovation, high-precision and low-cost metal grid manufacturing is achieved, and the method has remarkable application value in the fields of flexible electronics, transparent electrodes and the like.

Description

Technical Field

[0001] The present invention relates to the field of micro-nano manufacturing technology, and specifically to a micron-scale metal grid structure prepared by printing masking and electroplating thickening processes, which is suitable for transparent conductive films, flexible electronic devices, electromagnetic shielding, sensors and other fields. Background Art

[0002] Existing metal mesh fabrication technologies use photolithography and etching processes, which are costly and complex. Directly printing conductive inks, however, can produce lines with limited uniformity and line width, making it difficult to meet high-precision requirements. Furthermore, conventional mesh structures (such as single hexagons or squares) face a trade-off between transmittance, conductivity, and mechanical strength. This invention optimizes printing, masking, and electroplating processes, combined with a multi-shape design, to achieve a highly conductive, highly transmittance, and highly reliable metal mesh structure. Summary of the Invention

[0003] In order to solve the above problems, the present invention provides a multi-shaped micron-scale metal grid structure based on printing masking and electroplating thickening and a preparation method thereof.

[0004] The present invention is achieved through the following technical solutions:

[0005] A multi-shaped micron-scale metal grid structure based on printing masking and electroplating thickening has an opening diameter of 30-70μm, a line width of 15-30μm, and a height of 5-15μm. The material is copper, nickel or its alloys, and the grid units are circular, square, triangular, hexagonal or a combination thereof. Performance can be optimized through periodic or non-periodic arrangement.

[0006] Preferably, the metal grid has a square resistance of ≤10Ω / □ and a light transmittance of ≥85%.

[0007] Preferably, the alloy is nickel-cobalt or copper-nickel alloy.

[0008] A method for preparing a multi-shaped micron-scale metal grid structure based on printing masking and electroplating thickening includes the following steps:

[0009] a. Substrate pretreatment: depositing a seed layer on a flexible or rigid substrate;

[0010] b. Printing masking layer: Use nanoimprinting or inkjet printing to form a photoresist / resin mask to define the grid opening area;

[0011] c. Electroplating thickening: Electroplating metal in the opening area, controlling the current density (1-5A / dm 2 ) and time, so that the metal line height reaches 5-15μm;

[0012] d. Post-processing: remove the mask and seed layer, and anneal to improve conductivity.

[0013] Preferably, the flexible substrate is PET or PI.

[0014] Preferably, the rigid substrate is glass or silicon wafer.

[0015] Preferably, the seed layer is made of Cr or Cu.

[0016] Preferably, the electroplating current density in step c is 1-5A / dm 2 The electrolyte used contains copper sulfate or nickel sulfate and brightener.

[0017] Compared with the prior art, the present invention has the following beneficial effects:

[0018] The grid of the present invention has a line width to opening ratio of 1:2 to 1:4, a balanced light transmittance ≥ 85%, and a square resistance ≤ 10Ω / □. These parameters synergistically optimize the performance and accuracy of the grid.

[0019] The present invention uses printing masking to replace traditional photolithography, reducing manufacturing costs by more than 30%;

[0020] The metal grid of the present invention can be designed in various shapes. The triangular grid improves bending resistance and is suitable for flexible devices, while the circular opening reduces light scattering and is suitable for display panels.

[0021] The present invention achieves high-precision, low-cost metal grid manufacturing by optimizing the printing masking and electroplating processes and combining multi-shape structural innovations, and has significant application value in the fields of flexible electronics, transparent electrodes, etc. DETAILED DESCRIPTION

[0022] The present invention will be further described below in conjunction with the embodiments:

[0023] A multi-shaped micron-scale metal grid structure based on printing masking and electroplating thickening has an opening diameter of 30-70μm, a line width of 15-30μm, and a height of 5-15μm. The material is copper, nickel or its alloys, and the grid units are circular, square, triangular, hexagonal or a combination thereof. Performance can be optimized through periodic or non-periodic arrangement.

[0024] The alloy is nickel-cobalt or copper-nickel alloy.

[0025] A method for preparing a multi-shaped micron-scale metal grid structure based on printing masking and electroplating thickening includes the following steps:

[0026] a. Substrate pretreatment: depositing a seed layer on a flexible or rigid substrate;

[0027] b. Printing masking layer: Use nanoimprinting or inkjet printing to form a photoresist / resin mask to define the grid opening area;

[0028] c. Electroplating thickening: Electroplating metal in the opening area, controlling the current density (1-5A / dm 2 ) and time, so that the metal line height reaches 5-15μm;

[0029] d. Post-processing: remove the mask and seed layer, and anneal to improve conductivity.

[0030] The flexible substrate is PET or PI.

[0031] The rigid substrate is glass or silicon wafer.

[0032] The seed layer is made of Cr or Cu.

[0033] The electroplating current density in step c is 1-5A / dm 2 The electrolyte used contains copper sulfate or nickel sulfate and brightener.

[0034] Example 1 Preparation of square copper grid

[0035] The preparation method is as follows:

[0036] a. Substrate pretreatment: depositing a seed layer of Cu on the PET substrate;

[0037] b. Printing masking layer: Use nanoimprinting or inkjet printing to form a photoresist / resin mask to define the grid opening area;

[0038] c. Electroplating thickening: Electroplating metal in the opening area, controlling the current density (4A / dm 2 ) and time to make the metal line height reach 10μm;

[0039] d. Post-processing: remove the mask and seed layer, and anneal to improve conductivity.

[0040] The electroplating current density in step c is 4A / dm 2 The electrolyte used contains copper sulfate or nickel sulfate and brightener.

[0041] Finally, the metal grid specifications are obtained with a line width of 20μm, an opening of 50μm, a height of 10μm, a square resistance of 8Ω / □, and a transmittance of 88%, which is used for capacitive touch screens.

[0042] Example 2: Triangular nickel-cobalt alloy grid

[0043] a. Substrate pretreatment: depositing a seed layer of Cu on the silicon wafer substrate;

[0044] b. Printing masking layer: Use nanoimprinting or inkjet printing to form a photoresist / resin mask to define the grid opening area;

[0045] c. Electroplating thickening: Electroplating metal in the opening area, controlling the current density (3A / dm2 ) and time, so that the metal line height reaches 12μm;

[0046] d. Post-processing: remove the mask and seed layer, and anneal to improve conductivity.

[0047] The electroplating current density in step c is 3A / dm 2 The electrolyte used contains copper sulfate or nickel sulfate and brightener.

[0048] Finally, the metal grid specifications are 25μm line width, 60μm opening, 12μm height, and the resistance change is less than 5% when the tensile deformation is 10%, which is suitable for wearable devices.

[0049] The present invention achieves high-precision, low-cost metal grid manufacturing by optimizing the printing masking and electroplating processes and combining multi-shape structural innovations, and has significant application value in the fields of flexible electronics, transparent electrodes, etc.

[0050] In summary, the above is only a preferred embodiment of the present invention and is not intended to limit the scope of implementation of the present invention. All equivalent changes and modifications of the shape, structure, characteristics and spirit described in the scope of the claims of the present invention should be included in the scope of the claims of the present invention.

Claims

1. A multi-shaped micron-scale metal mesh structure based on printing masking and electroplating thickening, characterized by: The metal grid has an opening diameter of 30-70 μm, a line width of 15-30 μm, and a height of 5-15 μm. The material is copper, nickel or their alloys. The grid units are circular, square, triangular, hexagonal or a combination thereof. Performance can be optimized through periodic or non-periodic arrangement.

2. The multi-shaped micron-scale metal mesh structure based on printing masking and electroplating thickening according to claim 1, characterized in that: The metal grid has a square resistance of ≤10Ω / □ and a light transmittance of ≥85%.

3. The multi-shaped micron-scale metal mesh structure based on printing masking and electroplating thickening according to claim 1, characterized in that: The alloy is nickel-cobalt or copper-nickel alloy.

4. A method for preparing a multi-shaped micron-sized metal mesh structure based on printing masking and electroplating thickening according to claim 1, characterized in that: The steps include: a. Substrate pretreatment: depositing a seed layer on a flexible or rigid substrate; b. Printing masking layer: Use nanoimprinting or inkjet printing to form a photoresist / resin mask to define the grid opening area; c. Electroplating thickening: Electroplating metal in the opening area, controlling the current density and time to make the metal line height reach 5-15μm; d. Post-processing: remove the mask and seed layer, and anneal to improve conductivity.

5. The method for preparing a multi-shaped micron-sized metal mesh structure based on printing masking and electroplating thickening according to claim 4, characterized in that: The flexible substrate is PET or PI.

6. The method for preparing a multi-shaped micron-sized metal mesh structure based on printing masking and electroplating thickening according to claim 4, characterized in that: The rigid substrate is glass or silicon wafer.

7. The method for preparing a multi-shaped micron-sized metal mesh structure based on printing masking and electroplating thickening according to claim 4, characterized in that: The seed layer is made of Cr or Cu.

8. The method for preparing a multi-shaped micron-sized metal mesh structure based on printing masking and electroplating thickening according to claim 4, characterized in that: The electroplating current density in step c is 1-5A / dm 2 The electrolyte used contains copper sulfate or nickel sulfate and brightener.