Method for etching and filling deep trenches
US8273664B2 · kind B2 · utility
4Cited by
3References
13Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jun 8, 2011 |
| Grant date | Sep 25, 2012 |
| Priority date | — |
| Expiry date | Jun 8, 2031 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/76232
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A method of etching and tilling deep trenches is disclosed, which includes: forming an ONO(oxide-nitride-oxide) sandwich layer on a semiconductor substrate; forming deep trenches by using top oxide of the sandwich layer as a stop layer; removing the top oxide and middle SiN of the sandwich layer; tilling the deep trenches with epitaxial film or polysilicon film; polishing the wafer to get a planarized surface by stopping at the surface of the bottom oxide layer; removing the bottom oxide layer.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.