Method for forming a bottom corner rounded STI
US6524930B1 · kind B1 · utility
8Cited by
10References
21Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Apr 25, 2002 |
| Grant date | Feb 25, 2003 |
| Priority date | — |
| Expiry date | Apr 25, 2022 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/76235
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
Methods are disclosed for the formation of isolation structures and trenches in semiconductor devices, in which lower corners of an isolation trench are rounded after trench formation using an oxidation process which oxidizes substrate material from the trench sidewalls and bottom faster than from the lower corners of the trench. The oxide formed during the rounding process is then removed prior to performing other etch processes, to expose substrate material having rounded lower corners. Thereafter, a liner is formed and the trench is filled with dielectric material to complete the isolation structure.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.