Effective near neutral pH etching solution for molybdenum or tungsten
US4995942A · kind A · utility
15Cited by
1References
21Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Apr 30, 1990 |
| Grant date | Feb 26, 1991 |
| Priority date | — |
| Expiry date | Apr 30, 2010 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC23F1/14
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
A neutral or near neutral pH etching solution for effectively etching molybdenum and tungsten including: an aqueous ferricyanide ion solution, a soluble molybdate or tungstate, and an essential compound such that upon combination of said soluble molybdate or tungstate and said essential compound, a heteropoly compound is formed in which said essential compound contributes at least one heteroatom to said heteropoly compound. The etching solution is most preferably used for etching molybdenum or tungsten which is adhered or proximate to a base-sensitive material.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.