Method of fabricating deep-shallow trench isolation
US6214696A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Sep 10, 1999 |
| Grant date | Apr 10, 2001 |
| Priority date | — |
| Expiry date | Sep 10, 2019 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/76232
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
The method includes forming a pad oxide, a polysilicon layer over a substrate. Next, an oxide layer is formed over the polysilicon layer. An opening is formed in the oxide layer, the polysilicon layer, and the pad layer. A trench is formed by etching the substrate using the oxide layer as a mask. A sidewall structure is then formed on the opening. Next, an exposed portion of the substrate is etched by using the sidewall structure as a mask. The sidewall structure and the oxide layer are then removed. An oxide and an oxynitride layer are then formed on the aforesaid feature. A semiconductor layer is then formed over the oxynitride layer. A portion of the semiconductor layer is oxidized for forming an insulating layer. Finally, a refilling layer is formed over the insulating layer and the substrate is planarized for having a planar surface.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.