Etching solution
US9399734B2 · kind B2 · utility
1Cited by
3References
6Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Apr 8, 2008 |
| Grant date | Jul 26, 2016 |
| Priority date | — |
| Expiry date | Dec 25, 2028 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/76814
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
An etching solution, a process of producing the same, and an etching process using the same, in which the etching solution includes hydrofluoric acid (a), ammonium fluoride (b), and salt (c) formed between hydrogen fluoride and a base having a boiling point higher than that of ammonia; the concentration of ammonium fluoride (b) is not higher than 8.2 mol/kg, and the total amount of ammonium fluoride (b) and salt (c) formed between hydrogen fluoride and a base having a boiling point higher than that of ammonia is not less than 9.5 mol/kg.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.