Claims
- 1. A process for electroless gold plating a workpiece, comprising the steps of:
- contacting said workpiece with an electroless gold plating solution, the electroless gold plating solution comprising water, a thiosulfato gold (I) complex in an amount of 0.001 to 0.2 mol/l, a thiosulfate in an amount of 0.001 to 0.5 mol/l, thiourea, a pH regulator and a stabilizer; and
- depositing gold from said electroless gold plating solution on said workpiece by electroless deposition.
- 2. A process according to claim 1, wherein said workpiece includes a metallic surface, and the gold is deposited on said metallic surface.
- 3. A process according to claim 2, wherein said contacting is performed by immersing said metallic surface in said electroless gold plating solution.
- 4. A process according to claim 3, wherein said metallic surface is a gold surface.
- 5. A process according to claim 4, wherein said gold surface is gold formed by displacement plating.
- 6. A process according to claim 4, wherein said gold surface is gold formed by electroplating.
- 7. A process according to claim 1, wherein said solution is at a temperature of 60.degree.-90.degree. C. during said contacting.
- 8. An electroless gold plating process, comprising the steps of:
- forming a first conductor material on a substrate;
- forming a second conductor made from nickel on said first conductor material;
- forming a gold film, by displacement gold plating, on said second conductor; and
- forming a further gold film by electroless gold plating on said gold film, said electroless gold plating being performed by contacting said gold film with an electroless gold plating solution comprising water, a thiosulfato gold (I) complex in an amount of 0.001 to 0.2 mol/l, a thiosulfate in an amount of 0.001 to 0.5 mol/l, thiourea, a pH regulator and a stabilizer, and electrolessly depositing said further gold film from said electroless gold plating solution.
- 9. A process according to claim 8, wherein said substrate is made of a ceramic material.
- 10. A process according to claim 8, wherein said first conductor material forms a bonding pad.
- 11. A process according to claim 8, wherein said first conductor material forms a lead.
- 12. A process according to claim 9, wherein the substrate is made of an alumina ceramic material.
- 13. A process according to claim 9, wherein the first conductor material is tungsten.
Priority Claims (2)
Number |
Date |
Country |
Kind |
60-226738 |
Oct 1985 |
JPX |
|
61-88269 |
Apr 1986 |
JPX |
|
Parent Case Info
This application is a divisional application of application Ser. No. 918,498, filed Oct. 14, 1986 now abandoned.
US Referenced Citations (2)
Foreign Referenced Citations (3)
Number |
Date |
Country |
2803147 |
Jul 1979 |
DEX |
0150762 |
Sep 1981 |
DDX |
1203131 |
Aug 1970 |
GBX |
Divisions (1)
|
Number |
Date |
Country |
Parent |
918498 |
Oct 1986 |
|