Thiourea- and cyanide-free bath and process for electrolytic etching of gold
US7150820B2 · kind B2 · utility
2Cited by
50References
13Claims
0Family size
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Inventors
Key dates
| Filing date | Sep 22, 2003 |
| Grant date | Dec 19, 2006 |
| Priority date | — |
| Expiry date | Jul 26, 2024 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC25F3/02
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
An aqueous thiourea-free gold etching bath for electrolytically etching gold from a microelectronic workpiece. One embodiment of the aqueous thiourea-free bath contains: (a) about 0.5–1.5 M iodide; (b) about 0.1–0.3 M sulfite; and (c) about 1.0–3.0 g/L wetting agent. The bath is useful in a process for electrolytically etching gold from a microelectronic workpiece. A tool system in which the baths and processes of the present invention may be used is also described.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.