Method of depositing high-quality SiGe on SiGe substrates
US7008864B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 25, 2002 |
| Grant date | Mar 7, 2006 |
| Priority date | — |
| Expiry date | Oct 25, 2022 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/02532
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
This invention provides a method of depositing high-quality Si or SiGe epitaxial layers on SiGe substrates. By first depositing a thin Si seed layer on the SiGe substrate, the quality of the seed layer and of the subsequently deposited layers is greatly improved over what is obtained from depositing SiGe directly onto the SiGe substrate. Indeed, whereas the RMS surface roughness of the deposition of SiGe directly on SiGe, as measured by atomic-force microscopy (AFM), was 3–4 nm, it was more than an order of magnitude better when a thin Si seed layer was employed. This work was performed on an ultra-high-vacuum chemical vapor deposition (UHV/CVD) system; however, the same method would apply to other deposition systems such as atmospheric-pressure, low-pressure and rapid-thermal CVD.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.