Method of fabricating semiconductor devices including PMOS devices having embedded SiGe
US9449834B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 4, 2011 |
| Grant date | Sep 20, 2016 |
| Priority date | — |
| Expiry date | Nov 11, 2032 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10D62/822
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A method of fabricating semiconductor device is provided. First, a recess having a substantially rectangular cross section is formed in a substrate. Then, oxide layers are formed on sidewalls and bottom of the recess by oxygen ion implantation process, wherein oxide layer on sidewalls of recess is thinner than oxide layer on bottom of recess. Thereafter, oxide layer on sidewalls of recess is completely removed, and only a portion of oxide layer on bottom of recess remains. Then, sidewalls of recess are shaped into Σ form by orientation selective wet etching using oxide layer remained on bottom of recess as a stop layer. Finally, oxide layer on bottom of recess is removed. By forming oxide layer on bottom of recess and using it as stop layer in subsequent orientation selective wet etching, the disclosed method can prevent a Σ-shaped recess with a cuspate bottom.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.