Method for fabricating silicon-on-insulator structures
US5057450A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 1, 1991 |
| Grant date | Oct 15, 1991 |
| Priority date | — |
| Expiry date | Apr 1, 2011 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S148/135
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A fabrication method for forming SOI structures where perfect material is grown epitaxially on a substrate and then, through a series of selective etches and oxidations, an insulating layer is formed below the epitaxial silicon. In the method, low temperature epitaxial techniques are employed to grow a layered structure including a first layer p++ silicon on a substrate wafer, a layer of intrinsic silicon is then formed on the first p++ silicon layer, and a second layer of p++ silicon is formed on the intrinsic silicon layer, and a finally a layer of p-silicon is fabricated on top of the second p++ silicon layer. Grooves are formed through the p-layer, the second p++ silicon layer, the intrinsic silicon layer, and stopped in the first p++ silicon layer. An etch is then employed to remove the intrinsic layer long enough for the p++ silicon layer to be totally undercut, leaving an air gap between the two p++ silicon layers. An oxidation step is then performed to form a bottom insulator consisting of the oxidized first p++ silicon layer and on an upper insulator consisting of the oxidized second p++ silicon layer.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.