A type-II AlInP/AlGaAsSb/InP double heterojunction bipolar transistor (DHBT) with composition-graded Al content in the base is designed and grown by molecular beam epitaxy. Compared with composition-graded GaAsSb and InGaAsSb bases in DHBT, the graded AlGaAsSb base can generate a larger built-in electric field, thus reducing base transit time and improving device speed. We have fabricated AlGaAsSb graded base DHBTs and demonstrated fT/f MAX450/510GHz for a 0.3 × 2μm2 device.
- double heterojunction bipolar transistor (DHBT)
- millimeter wave
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Electrical and Electronic Engineering