Selective epitaxial formation of semiconductive films
US9312131B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 31, 2012 |
| Grant date | Apr 12, 2016 |
| Priority date | — |
| Expiry date | May 31, 2032 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10D62/822
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
Epitaxial layers are selectively formed in semiconductor windows by a cyclical process of repeated blanket deposition and selective etching. The blanket deposition phases leave non-epitaxial material over insulating regions, such as field oxide, and the selective etch phases preferentially remove non-epitaxial material while deposited epitaxial material builds up cycle-by-cycle. Quality of the epitaxial material improves relative to selective processes where no deposition occurs on insulators. Use of a germanium catalyst during the etch phases of the process aid etch rates and facilitate economical maintenance of isothermal and/or isobaric conditions throughout the cycles. Throughput and quality are improved by use of trisilane, formation of amorphous material over the insulating regions and minimizing the thickness ratio of amorphous:epitaxial material in each deposition phase.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.