Tungsten-silicide reoxidation process including annealing in pure nitrogen and subsequent oxidation in oxygen
US4833099A · kind A · utility
25Cited by
6References
12Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Jan 7, 1988 |
| Grant date | May 23, 1989 |
| Priority date | — |
| Expiry date | Jan 7, 2008 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S148/147
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A tungsten silicide reoxidation technique for forming a reoxidation layer in a CMOS device is disclosed. After forming an insulated gate member, which has a silicon-rich tungsten silicide layer overlying a polysilicon layer, it is first oxidized and the oxide is removed to expose WSi for forming a particular source/drain doped device. Then it is annealed in a substantially pure nitrogen ambient for a given time period. A subsequent growth of the reoxidation layer over the gate member by introducing oxygen results in a substantially planarized surface. The combination between tungsten and oxygen is prevented.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.