Conductive particles for anisotropic conductive interconnection

Abstract

Embodiments of the present invention include a conductive particle that includes a conductive nickel/gold (Ni/Au) complex metal layer having a phosphorous content of less than about 1.5 weight percent formed on the surface of a polymer resin particle. Methods of forming the same are also included. A conductive particle with a Ni/Au complex metal layer having less than about 1.5 weight percent of phosphorous may have relatively high conductivity while providing relatively good adhesion of the Ni/Au metal layer to the polymer resin particle.

Description

Claims

1. A conductive particle comprising a conductive nickel/gold (Ni/Au) complex metal layer having a phosphorous content of less than about 1.5 weight percent formed on the surface of a polymer resin particle.

2. The conductive particle according to claim 1, wherein the phosphorous content is in a range of about 0.3 to about 1.5 weight percent.

3. The conductive particle according to claim 1, wherein the Ni/Au complex metal layer comprises a first layer that is substantially Ni encompassed by a second layer that is substantially Au.

4. The conductive particle according to claim 1, wherein the Ni/Au complex metal layer comprises a Au density gradient wherein the Ni/Au complex metal layer consists essentially of Ni at the surface of the polymer resin particle and consists essentially of Au at the outer surface of the conductive particle.

5. The conductive particle according to claim 1, wherein the Ni/Au complex metal layer includes a gold plating layer having a thickness in a range of about 0.01 to about 0.5 μm.

6. The conductive particle according to claim 1, wherein the difference between the 10% K value of the polymer resin particle and the conductive particle is about 100 kgf/mm2 or less.

7. The conductive particle according to claim 1, wherein the polymer resin particle has a 10% K value in a range of about 200 to about 700 kgf/mm2.

8. The conductive particle according to claim 1, wherein the polymer resin particle has an average diameter of about 1 to about 20 μm, a CV value of about 10% or less and an aspect ratio of about 1.3 or less.

9. The conductive particle according to claim 1, wherein the polymer resin particle comprises a crosslinked polymer resin comprising a monomer selected from the group consisting of allyl compounds, polyethylene glycol diacrylate, polyethylene glycol dimethacrylate, polypropylene glycol diacrylate, polypropylene glycol dimethacrylate, pentaerythritol tetraacrylate, pentaerythritol tetramethacrylate, pentaerythritol triacrylate, pentaerythritol trimethacrylate, pentraerythritol diacrylate, pentaerythritol dimethacrylate, trimethylolpropane triacrylate, trimethylol propane trimethacrylate, dipentaerythritol hexaacrylate, dipentaerythritol hexamethacrylate, dipentaerythritol pentaacrylate, dipentaerythritol pentamethacrylate, glycerol triacrylate and glycerol trimethacrylate.

10. An anisotropic adhesive composition comprising the conductive particle of claim 1.

11. A method of forming a conductive particle comprising performing electroless Ni plating of a polymer resin particle followed by performing gold plating of the polymer resin particle to form the conductive particle;wherein the conductive particle has a Ni/Au complex metal layer having a phosphorous content of less than about 1.5 weight percent.

12. A method of forming a conductive particle comprising performing gold plating during electroless Ni plating of a polymer resin particle to form the conductive particle;wherein the conductive particle has a Ni/Au complex metal layer having a phosphorous content of less than about 1.5 weight percent.