Method for independent control of polycrystalline silicon-germanium in a silicon-germanium HBT and related structure
US6365479B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | Sep 22, 2000 |
| Grant date | Apr 2, 2002 |
| Priority date | — |
| Expiry date | Sep 22, 2020 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/0262
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
In one embodiment a precursor gas for growing a polycrystalline silicon-germanium region and a single crystal silicon-germanium region is supplied. The precursor gas can be, for example, GeH4. The polycrystalline silicon-germanium region can be, for example, a base contact in a heterojunction bipolar transistor while the single crystal silicon-germanium region can be, for example, a base in the heterojunction bipolar transistor. The polycrystalline silicon-germanium region can be grown in a mass controlled mode at a certain temperature and a certain pressure of the precursor gas while the single crystal silicon-germanium region can be grown, concurrently, in a kinetically controlled mode at the same temperature and the same pressure of the precursor gas. The disclosed embodiments result in controlling the growth of the polycrystalline silicon-germanium independent of the growth of the single crystal silicon-germanium.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.