KR-20260067673-A - Method for manufacturing transparent electrode using conductive nano ink and transparent electrode manufactured thereby

Abstract

The present invention relates to a method for fabricating a transparent electrode using conductive nano ink, comprising the steps of: sequentially stacking a chrome mask (30) having a transparent electrode pattern formed thereon, a photosensitive material (10), and a substrate, and exposing them to ultraviolet light; developing after the ultraviolet light exposure to form a photosensitive material having a transparent electrode pattern formed thereon on the substrate; a step of modifying the photosensitive material having the transparent electrode pattern formed thereon (hereinafter referred to as a 'sacrificial layer') to remove hydrophobicity to the conductive nano ink; b step of applying the conductive nano ink to the sacrificial layer; c step of removing residual conductive nano ink on the upper surface of the sacrificial layer by a spin process; d step of pre-sintering the sacrificial layer to reduce the conductive nano ink inside the sacrificial layer to a solid state; and a step of removing the sacrificial layer to obtain a conductive nano ink pattern of the transparent electrode pattern; and e step of further heat-treating the conductive nano ink pattern to improve conductivity. The present invention provides a method for fabricating a transparent electrode using a conductive nano ink, which has the advantage of simplifying and speeding the process and enabling the formation of a precise large-area fine transparent electrode pattern by using a method of forming a photosensitive material into a transparent electrode mold through a photolithography process.

Inventors

• 김판겸
• 정성일
• 하태규

Assignees

• 한국전기연구원

Dates

Publication Date

20260513

Application Date

20241106

Claims (7)

1. A step of sequentially stacking a chrome mask having a transparent electrode pattern, a photosensitive material, and a substrate, and exposing to ultraviolet light; A step of forming a photosensitive material having a transparent electrode pattern formed on a substrate by developing after the above-mentioned ultraviolet exposure; Step a of modifying a photosensitive material (hereinafter referred to as a 'sacrificial layer') having the above-mentioned transparent electrode pattern formed thereon to remove hydrophobicity to the conductive nanoink; Step b of applying conductive nano ink to the sacrificial layer; Step c, which removes residual conductive nanoink on the upper surface of the sacrificial layer using a spin process; Step d, which involves pre-sintering the sacrificial layer to reduce the conductive nano-ink inside the sacrificial layer to a solid state; Step e, which involves removing the sacrificial layer to obtain a conductive nanoink pattern of a transparent electrode pattern and further heat-treating the conductive nanoink pattern to improve conductivity. A method for fabricating a transparent electrode using conductive nano ink, characterized by comprising
2. In paragraph 1, the above step a A method for fabricating a transparent electrode using a conductive nano ink, characterized by being carried out by plasma treatment or ozone treatment.
3. In paragraph 1, the above step b A method for fabricating a transparent electrode using a conductive nano ink characterized by the conductive nano ink having a solid content dilution ratio of 0.1 wt% to 50 wt% with respect to water.
4. In claim 1, the spin process of step c is Run at a spin speed of 1000 rpm or higher A method for fabricating a transparent electrode using conductive nano ink, characterized by reducing the thickness of the residual conductive nano ink on the upper surface of the sacrificial layer.
5. In paragraph 1, the above step d A method for fabricating a transparent electrode using a conductive nano ink characterized by having a sintering temperature in the range of 90℃ to 120℃.
6. In paragraph 1 A method for fabricating a transparent electrode using a conductive nano ink, characterized in that the heat treatment temperature of step e above is 120℃ or higher.
7. A transparent electrode using a conductive nano ink produced according to one of claims 1 to 6.

Description

Method for manufacturing transparent electrode using conductive nano ink and transparent electrode manufactured thereby The present invention relates to a method for fabricating a transparent electrode by forming a transparent electrode pattern on a photosensitive material using a photolithography method, applying a conductive nanoink to the photosensitive material and heat-treating it, and removing the photosensitive material. Transparent electrode patterns are created by forming a material that has both high transparency and conductivity into a specific shape and utilizing it in various electronic devices. They are mainly used in touchscreens, solar cells, and OLEDs, and recently, they are also being applied to wearable devices and smart windows. Generally, the fabrication of a transparent electrode pattern is carried out in the following steps: substrate preparation, transparent electrode material deposition, patterning, and post-processing. The patterning step is a step of forming a pattern of a desired shape using methods such as photolithography, laser cutting, or inkjet printing, and the post-processing step is a step of increasing the stability of the pattern through heat treatment, plasma treatment, etc., as needed. Indium Tin Oxide (ITO) is the most widely used transparent electrode material for transparent electrode patterns; while it possesses high transmittance and conductivity, it has the disadvantages of being expensive and lacking flexibility. Silver nanowires have high conductivity and flexibility and are attracting attention as a material that can replace ITO, carbon nanotubes have high conductivity and mechanical strength and are suitable for flexible transparent electrodes, and graphene has excellent electrical and mechanical properties but has technical problems that make mass production and ensuring uniform quality difficult. As mentioned above, the patterning step utilizes methods such as photolithography, laser cutting, and inkjet printing, and we will examine the prior art related thereto below. Korean Patent Application No. 10-2015-0041441, 'Method for manufacturing a transparent electrode pattern', forms a transparent electrode pattern by filling a recessed substrate with a conductive nano-ink composition and transferring it twice. Korean Patent Application No. 10-2012-0126998, 'conductive nano ink composition, electrode wire and transparent electrode using the same,' forms a pattern using a conductive nano ink by jet printing. Korean Patent Application No. 10-2010-0040532, 'Large-area printing method of conductive ink', prints conductive nano-ink using a gravure printing method. Korean Patent Application No. 10-2010-0123722, 'Conductive ink and transparent electrode using the same', forms a transparent electrode by wet thin film coating using a carbon structure-based conductive ink. Korean Patent Application No. 10-2014-0059281, 'Method for manufacturing a hybrid transparent electrode and a hybrid transparent electrode,' forms a transparent electrode by filling a groove of a substrate having a groove with a conductive metal ink composition. Korean Patent Application No. 10-2021-0169160, 'Metal Micro-printing Method and Apparatus,' proposes a printing method capable of producing micro-patterns using the interference phenomenon of a laser beam on MOD ink. As such, prior art technologies form transparent electrode patterns by fabricating a stencil with a pre-formed printing pattern or by directly spraying the pattern; however, these methods have the problem of being complex processes or making it difficult to form large-area transparent patterns of precise microelectrodes. FIG. 1 is an explanatory diagram of an embodiment of the present invention. The present invention will be examined below with reference to the drawings. In describing the present invention, if it is determined that a detailed description of related known technologies or configurations may unnecessarily obscure the essence of the invention, such detailed description will be omitted. Furthermore, the terms described below are defined in consideration of their functions in the present invention; since these may vary depending on the intentions or practices of the user or operator, their definitions should be based on the content throughout this specification describing the present invention. The present invention will be examined below in conjunction with FIG. 1. In FIG. 1, step (S100) of the present invention is a step of sequentially stacking a chrome mask (30) with a transparent electrode pattern formed thereon, a photosensitive material (10), and a substrate (20), and exposing them to ultraviolet light. The desired transparent electrode pattern can be fabricated using a chrome mask (30), and can be fabricated with a fine line width of up to 1 µm considering the transmittance. The above substrate (20) is a glass substrate, and a substrate (20) on which HMDS (hexamethyldisilane) is deposited is used to increase the