Title :
Graded base type-II InP/GaAsSb DHBT with fT=475 GHz
Author :
Snodgrass, W. ; Bing-Ruey Wu ; Hafez, W. ; Keh-Yung Cheng ; Milton Feng
Author_Institution :
Dept. of Electr. & Comput. Eng., Univ. of Illinois, Urbana, IL, USA
Abstract :
The first demonstration of a type-II InP/GaAsSb double heterojunction bipolar transistor (DHBT) with a compositionally graded InGaAsSb to GaAsSb base layer is presented. A device with a 0.4×6 μm2 emitter dimensions achieves peak fT of 475 GHz (fmax=265 GHz) with current density at peak fT exceeding 12 mA/μm2. The structure consists of a 25-nm InGaAsSb/GaAsSb graded base layer and 65-nm InP collector grown by MBE with breakdown voltage /spl sim/4 V which demonstrates the vertical scaling versus breakdown advantage over type-I DHBTs.
Keywords :
III-V semiconductors; gallium arsenide; heterojunction bipolar transistors; indium compounds; molecular beam epitaxial growth; submillimetre wave transistors; 25 nm; 265 GHz; 475 GHz; 65 nm; DHBT; InGaAsSb-GaAsSb-InP; MBE; breakdown voltage; current density; graded base layer; type-II double heterojunction bipolar transistor; Bipolar transistors; Breakdown voltage; Current density; Cutoff frequency; Double heterojunction bipolar transistors; Electron emission; Heterojunction bipolar transistors; Indium gallium arsenide; Indium phosphide; Thermal conductivity; Heterojunction bipolar transistors (HBTs);
Journal_Title :
Electron Device Letters, IEEE
DOI :
10.1109/LED.2005.862673
