Self-exposure method for surface of conductive particles anchored in polymer layer, method of fabricating anisotropic conductive film using the self-exposure method and the anisotropic conductive film

Patent metadata

Field	Value
Publication number	US-11021616-B2
Application number	US-201816057582-A
Country	US
Kind code	B2
Filing date	Aug 7, 2018
Priority date	Jan 25, 2018
Publication date	Jun 1, 2021
Grant date	Jun 1, 2021

Abstract

Disclosed are a self-exposure method for a surface of conductive particles anchored in a polymer layer, a method of fabricating an anisotropic conductive film using the self-exposure method, and the anisotropic conductive film. A self-exposure method for a surface of conductive particles within a polymer layer may include controlling surface energy of multiple conductive particles so that a difference between surface energy of polymer to be used to fabricate the polymer layer and surface energy of the multiple conductive particles to be included in the polymer layer is a preset difference or more, forming a polymer solution by dissolving the polymer into a solvent in which the conductive particles having controlled surface energy have been mixed, and generating the polymer layer from which at least part of a surface of the multiple conductive particles has been externally exposed due to a difference in the surface energy by drying the polymer solution.

First claim

What is claimed is:

1. A self-exposure method for a surface of conductive particles within a polymer layer, the method comprising:
controlling a surface energy of multiple conductive particles so that a difference between a surface energy of polymer to be used to fabricate the polymer layer and the surface energy of the multiple conductive particles to be included in the polymer layer is a preset difference or more;
forming a polymer solution by dissolving the polymer into a solvent in which the conductive particles having controlled surface energy have been mixed; and
generating the polymer layer from which at least part of a surface of the multiple conductive particles has been externally exposed due to a difference not less than the preset difference between the surface energy of the polymer and the surface energy of the multiple conductive particles by drying the polymer solution,
wherein controlling the surface energy comprises controlling the surface energy of the conductive particles by coating a hydrophobic substance on the surface of the conductive particles if the polymer has a hydrophilic property or coating a hydrophilic substance on the surface of the conductive particles if the polymer has a hydrophobic property.

2. A self-exposure method for a surface of conductive particles within a polymer layer, the method comprising:
controlling a surface energy of multiple conductive particles so that a difference between a surface energy of polymer to be used to fabricate the polymer layer and the surface energy of the multiple conductive particles to be included in the polymer layer is a preset difference or more;
forming a polymer solution by dissolving the polymer into a solvent in which the conductive particles having controlled surface energy have been mixed; and
generating the polymer layer from which at least part of a surface of the multiple conductive particles has been externally exposed due to a difference not less than the preset difference between the surface energy of the polymer and the surface energy of the multiple conductive particles by drying the polymer solution,
wherein controlling the surface energy comprises stirring a hydrophobic substance if the polymer has a hydrophilic property or a hydrophilic substance if the polymer has a hydrophobic property by dissolving the substance into the solvent in which the multiple conductive particles have been mixed so that the substance is coated on the surface of the conductive particles.

3. The method of claim 2 , wherein controlling the surface energy comprises controlling a degree that the surface energy of the conductive particles is changed by adjusting content of the hydrophobic substance dissolved into the solvent in which the multiple conductive particles have been mixed or content of the hydrophilic substance dissolved into the solvent.

4. The method of claim 1 , wherein the hydrophobic substance or hydrophilic substance coated on the surface of the conductive particles has conductivity.

5. A self-exposure method for a surface of conductive particles within a polymer layer, the method comprising:
controlling a surface energy of multiple conductive particles so that a difference between a surface energy of polymer to be used to fabricate the polymer layer and the surface energy of the multiple conductive particles to be included in the polymer layer is a preset difference or more;
forming a polymer solution by dissolving the polymer into a solvent in which the conductive particles having controlled surface energy have been mixed; and
generating the polymer layer from which at least part of a surface of the multiple conductive particles has been externally exposed due to a difference not less than the preset difference between the surface energy of the polymer and the surface energy of the multiple conductive particles by drying the polymer solution, wherein:
the polymer comprises polyacrylonitrile having a hydrophilic property, and
controlling the surface energy comprises controlling the surface energy of the conductive particles by coating oleic acid on the surface of the conductive particles in order to assign a hydrophobic property.

6. The method of claim 1 , wherein controlling the surface energy comprises controlling the surface energy of the conductive particles by coating oleic acid having content of 20 wt % or more with respect to the polymer solution on the surface of the conductive particles in such a way as to stir the oleic acid by dissolving the oleic acid into the solvent in which the multiple conductive particles have been mixed.

7. The method of claim 1 , further comprising fabricating an anisotropic conductive film (ACF) by laminating an adhesive layer made of a non-conductive film (NCF) at a top and bottom of the polymer layer.

8. The method of claim 1 , wherein the polymer layer comprises polymer having tensile stress to limit a flow of the multiple conductive particles when the polymer layer connects the multiple conductive particles and a flow of resin occurs due to a bonding process.

9. The method of claim 1 , wherein generating the polymer layer comprises fabricating the polymer layer to limit a flow of the conductive particles by roll-to-roll-coating the polymer solution.

Assignees

• Korea Advanced Inst Sci & Tech

Inventors

• Paik Kyoungwook
• Yoon Dal Jin

Classifications

• H10P95/00

  Generic processes or apparatus for manufacture or treatments not covered by the other groups of this subclass · CPC title

• C08K9/04 Primary

  Ingredients treated with organic substances {(treated with macromolecular compounds C08K9/08)} · CPC title

• C08K2201/001

  Conductive additives · CPC title

• C09J2203/326

  for bonding electronic components such as wafers, chips or semiconductors · CPC title

• H01B1/20

  Conductive material dispersed in non-conductive organic material {(organic macromolecular compounds or compositions C08)} · CPC title