Process for fabricating devices having dielectric isolation utilizing anodic treatment and selective oxidation
US3954523A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 14, 1975 |
| Grant date | May 4, 1976 |
| Priority date | — |
| Expiry date | Apr 14, 1995 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S148/117
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A process for forming complete dielectrically isolated monocrystalline silicon regions on a substrate by depositing a first epitaxial silicon layer embodying an N-type impurity on a low resistivity silicon substrate embodying a P-type impurity, forming annular P-type impurity regions in the first epitaxial layer, depositing the second epitaxial layer embodying an N-type impurity on the first epitaxial layer, forming annular P-type impurity regions in the second epitaxial layer in registry with the annular regions in the first epitaxial layer, converting the silicon substrate and the annular P-type regions in the first and second epitaxial layers into porous silicon material by an anodic treatment carried out in an aqueous solution of hydrofluoric acid, and oxidizing the porous silicon material to form silicon oxide. A semiconductor structure having a backing substrate of silicon oxide with monocrystalline silicon islands embedded therein. A preferred embodiment includes low resistivity regions that extend through the substrate.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.