Heterojunction bipolar transistor structure with a bandgap graded hole barrier layer
US10818781B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 20, 2020 |
| Grant date | Oct 27, 2020 |
| Priority date | — |
| Expiry date | Feb 20, 2040 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10D62/852
Abstract
Provided is a heterojunction bipolar transistor (HBT) structure with a bandgap graded hole barrier layer, including: a sub-collector layer including an N-type group III-V semiconductor on a substrate, a collector layer on the sub-collector layer and including a group III-V semiconductor, a hole barrier layer on the collector layer, a base layer on the hole barrier layer and including a P-type group III-V semiconductor, an emitter layer on the base layer and including an N-type group III-V semiconductor, an emitter cap layer on the emitter layer and including an N-type group III-V semiconductor, and an ohmic contact layer on the emitter cap layer and including an N-type group III-V semiconductor. Bandgaps of the hole barrier layer at least include a gradually increasing bandgap from the base layer towards the collector layer and a largest bandgap of the hole barrier layer is greater than bandgap of the base layer.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.