Heterojunction bipolar transistor including collector/base heterojunction achieving high operation efficiency
US6399969B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | May 19, 2000 |
| Grant date | Jun 4, 2002 |
| Priority date | — |
| Expiry date | May 19, 2020 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10D10/821
Abstract
A hetero junction bipolar transistor has an emitter region, a base region, a collector region and a subcollector region which are serially arranged. The collector region includes a plurality of sub-regions. An energy bandgap in each of the sub-regions is constant or linearly changes, and an energy band edge where mobile charge carriers run in the collector region is continuous at each boundary between the sub-regions. Two-dimensional or quasi-two-dimensional charge layer is formed at the boundary of the sub-regions so as to compensate quasi-electric field caused by differences in electron affinity and energy bandgap between the sub-regions. The mobile charge carriers pass through the collector region from the base region without encountering barriers and thereby this heterojunction bipolar transistor achieves a high operating efficiency.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.