Backside gettering method employing a monocrystalline germanium-silicon layer
US5229306A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 27, 1989 |
| Grant date | Jul 20, 1993 |
| Priority date | — |
| Expiry date | Dec 27, 2009 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/3221
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A method for gettering metal atoms (28) from a subsequently contaminated silicon substrate (12) is disclosed. A smoothed or polished first surface (16) has a thin germanium silicon layer (20) deposited thereon. A silicon layer (24) is deposited onto the germanium silicon layer (20) to seal the layer (20) between the substrate (12) and the silicon layer (24). Electronic components (26) are fabricated on a second surface (14) of the silicon substrate (12) which causes the metal atoms (28) to contaminate the substrate as a result of contamination in normal processing (12). As the substrate (12) is heated during normal processing of the devices, metal atoms (28) in the substrate of a result of contamination, diffuse in the substrate (12) to the misfit dislocations at the germanium-silicon (20)/silicon interface.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.