Selective oxidation process
US5923994A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Feb 6, 1998 |
| Grant date | Jul 13, 1999 |
| Priority date | — |
| Expiry date | Feb 6, 2018 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/76202
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A selective oxidation process includes conducting a former phase of an oxidation process employing a thick mask layer to produce an oxide layer having a thickness less than the finished thickness of a desired semiconductor device isolation insulator. Then the thickness of the mask layer is reduced and a latter phase of the oxidation process using the reducing thickness mask layer is performed to produce the desired semiconductor device isolation insulator having the ultimate thickness. The use of both a thick mask layer and a reduced thickness mask layer for various phases of the oxidation process limits both the growth of the bird's beak and the growth of crystalline defects in the bird's beak.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.