Tungsten-silicide reoxidation technique using a CVD oxide cap
US4774201A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 7, 1988 |
| Grant date | Sep 27, 1988 |
| Priority date | — |
| Expiry date | Jan 7, 2008 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S148/118
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A tungsten silicide reoxidation technique for forming a reoxidation layer in a CMOS MOSFET device. After forming an insulated gate member, which has a tungsten silicide layer overlying a polysilicon layer, a CVD oxide layer is deposited on the exposed and crystallized tungsten silicide layer to function as a cap prior to the formation of the reoxidation layer. The CVD oxide layer operates to slow the passage of oxygen atoms to combine with the tungsten atoms of the silicide layer but allows free migration of silicon atoms from the polysilicon layer to the tungsten silicide surface and combine with the oxygen atoms in forming a substantially planarized and uncontaminated reoxidation layer without the requirement of a substantially pure nitrogen ambient.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.