Protection of silicon from phosphoric acid using thick chemical oxide
US7384869B2 · kind B2 · utility
2Cited by
10References
17Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Apr 7, 2005 |
| Grant date | Jun 10, 2008 |
| Priority date | — |
| Expiry date | Apr 15, 2025 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/32
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A method for protecting exposed silicon from attack by phosphoric acid during wet etching and stripping processes is provided. According to various embodiments of the method, a thick chemical oxide layer can be formed on the exposed silicon to protect the exposed portion from etching by phosphoric acid. The method can include exposing the silicon to at least one of a hot ozonated sulfuric acid and a hot peroxide sulfuric acid to form the thick chemical oxide.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.