Heterojunction bipolar transistor having non-uniformly doped collector for improved safe-operating area
US7012288B2 · kind B2 · utility
9Cited by
3References
4Claims
0Family size
Assignee
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Key dates
| Filing date | Oct 8, 2002 |
| Grant date | Mar 14, 2006 |
| Priority date | — |
| Expiry date | Dec 21, 2022 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10D62/137
Abstract
The safe-operating area (SOA) in a heterojunction bipolar transistor (HBT) is improved by providing a collector region in the transistor having a graded (uniformly or stepped) doping between the base region and the underlying subcollector region with the collector doping being lower near the base and higher near the subcollector and with the collector doping being less than the doping of the subcollector. The non-uniformly doped collector reduces Kirk effect induced breakdown when collector current increases.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.