Controlled, gas phase process for removal of trace metal contamination and for removal of a semiconductor layer
US5589422A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jan 15, 1993 |
| Grant date | Dec 31, 1996 |
| Priority date | — |
| Expiry date | Jan 15, 2013 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/02046
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A ultra-clean, ULSI-supportable process is described for cleaning and etching very thin layers of a semiconductor surface in a gaseous ambient at approximately room temperature. An oxidized surface is etched and cleaned in the vapors of azeotropic, aqueous acids. The cleaning properties of the vapors of the aqueous acids are such that metallic contaminants residing at the surface or within the oxidized layer are complexed and later rinsed away in a rinsing process. The surface is then re-oxidized in an ozone ambient, the resultant oxidation reaction being self-limiting such that the oxide layer is grown to a consistent, predetermined thickness. The process may be repeated any number of times depending on the depth at which any contaminants reside.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.