Title :
GaInP/AlGaAs/GaInP double heterojunction bipolar transistors with zero conduction band spike at the collector
Author :
Lye, Beng-Chye ; Houston, P.A. ; Yow, Ho-Kwang ; Button, C.C.
Author_Institution :
Dept. of Electron. & Electr. Eng., Sheffield Univ., UK
fDate :
12/1/1998 12:00:00 AM
Abstract :
Al0.11Ga0.89As was used in the base, next to the GaInP collector of a DHBT, to eliminate the conduction band spike. The DHBT´s demonstrated high breakdown voltages, BVCEO and BV CBO of 44.5 V and 54.5 V (gain≈20), respectively, for a 1-μm-thick collector doped to 2×1016 cm-3 with no voltage dependence of the current gain. Magneto-transport measurements were made on the AlGaAs bases and indicated limitations on the maximum practical base doping due to the inferior minority electron mobility and lifetime when compared with equivalently doped GaAs. Grading in the base from Al0.11Ga0.89As at the collector to Al0.21Ga0.79As at the emitter introduced a quasielectric field in the base, reduced the base transit time by a factor of ~2.5, and improved the gain over ungraded devices with the same average Al concentration
Keywords :
III-V semiconductors; aluminium compounds; carrier lifetime; conduction bands; electron mobility; gallium arsenide; gallium compounds; heterojunction bipolar transistors; indium compounds; minority carriers; semiconductor device breakdown; GaInP-AlGaAs-GaInP; GaInP/AlGaAs/GaInP double heterojunction bipolar transistor; base doping; base transit time; breakdown voltage; collector; conduction band spike; current gain; magnetotransport; minority electron lifetime; minority electron mobility; quasielectric field; Bipolar transistors; Breakdown voltage; Doping; Double heterojunction bipolar transistors; Electron mobility; Epitaxial growth; Gallium arsenide; Heterojunction bipolar transistors; Microwave devices; Tunneling;
Journal_Title :
Electron Devices, IEEE Transactions on
