Metal coating, forming method thereof, and metal wiring

• US 20090197045A1
• Filed: 05/17/2006
• Published: 08/06/2009
• Est. Priority Date: 05/30/2005
• Status: Active Grant

• Current Assignee: Sumitomo Electric Industries Limited (Sumitomo Corporation)
• Original Assignee: Sumitomo Electric Industries Limited (Sumitomo Corporation)
• Inventors: Shimoda, Kohei, Okada, Issei
• Granted Patent: US 8,507,104 B2
• Time in Patent Office: Days
• US Class Current: 428/141
• CPC Class Codes: C22C 5/06 Alloys based on silver
• CPC Class Codes: C23C 24/00 Coating starting from inorganic powder spraying of the coating material in molten state C23C4/00; solid state diffusion C23C8/00 - C23C12/00
• CPC Class Codes: C23C 24/08 by application of heat or pressure and heat C23C24/04 takes precedence
• CPC Class Codes: C23C 26/00 Coating not provided for in groups C23C2/00 - C23C24/00
• CPC Class Codes: H01B 1/02 mainly consisting of metals or alloys
• CPC Class Codes: H01B 1/22 the conductive material comprising metals or alloys
• CPC Class Codes: H05K 1/097 Inks comprising nanoparticles and specially adapted for being sintered at low temperature H05K1/095 takes precedence
• CPC Class Codes: Y10T 428/12 All metal or with adjacent metals
• CPC Class Codes: Y10T 428/12014 having metal particles
• CPC Class Codes: Y10T 428/24355 Continuous and nonuniform or irregular surface on layer or component [e.g., roofing, etc.]
• CPC Class Codes: Y10T 428/24917 including metal layer

Abstract

The present invention provides a metal coating formed by baking after applying a metal-nanoparticles-dispersed liquid onto a surface of a base material, the metal-nanoparticles-dispersed liquid being composed of metal nanoparticles, water, and a dispersant having a molecular weight of 2000-30000 and having a solid form at room temperature, wherein the metal coating comprises an alloy including (1) Ag and (2) at least one kind of metal selected from the group consisting of Au, Pt, Pd, Ru, Ir, Sn, Cu, Ni, Fe, Co, Ti and In, the content ratio of Ag being 80-99.9% by atomic percent in the total quantity of the alloy, and wherein the metal coating has an average grain size of 0.2-5 μm. The metal coating has small surface roughness, and superior smoothness and denseness, and has excellent properties for etching and adhesion to a base material. Also, the invention provides a method of forming such metal coating as well as a metal wiring formed by pattern formation of the metal coating.

Claims

1. A metal coating formed by baking after applying a metal-nanoparticles-dispersed liquid onto a surface of a base material, the metal-nanoparticles-dispersed liquid being composed of metal nanoparticles, water, and a dispersant having a molecular weight of 2000-30000 and having a solid form at room temperature,

wherein the metal coating comprises an alloy including (1) Ag and (2) at least one kind of metal selected from the group consisting of Au, Pt, Pd, Ru, Ir, Sn, Cu, Ni, Fe, Co, Ti and In, the content ratio of Ag being 80-99.9% by atomic percent in the total quantity of the alloy, and

wherein the metal coating has an average grain size of 0.2-5 μ

m.

2. A metal coating formed according to claim 1, wherein the metal coating comprises an alloy including (1) Ag and (2-1) a first metal, i.e., at least one kind of metal selected from the group consisting of Au, Pt, Pd, Ru, and Ir, and (2-2) a second metal, i.e., at least one kind of metal selected from the group consisting of Sn, Cu, Ni, Fe, Co, Ti and In, the content ratio of the second metal being 0.1-2% by atomic percent in the total quantity of the alloy.

3. A metal coating as set forth in claim 1, wherein the metal coating has an arithmetic mean roughness Ra of 100 nm or less.

4. A metal coating as set forth in claim 1, wherein the metal coating is formed using a metal-nanoparticles-dispersed liquid containing a water soluble organic solvent.

5. A metal coating as set forth in claim 1, wherein the metal coating is formed using a metal-nanoparticles-dispersed liquid having an electric conductivity of 5 mS/cm or more.

6. A method of forming a metal coating set forth in claim 1, comprising the steps of:

applying a metal-nanoparticles-dispersed liquid onto a surface of a base material, the metal-nanoparticles-dispersed liquid being composed of metal nanoparticles, water and a dispersant having a molecular weight of 2000-30000 and having a solid form at room temperature;

forming a coated film by drying the so-applied liquid; and

forming a metal coating by baking the coated film at a temperature of 700°

C. or less.

7. A metal wiring formed by pattern formation of a metal coating set forth in claim 1.

8. A metal wiring as set forth in claim 7, wherein the metal wiring is made by etching in pattern formation of the metal coating formed on a base material.