Transit time effect in high-frequency characteristics of HBTs

Author

Lee, S. ; Gopinath, A.

Author_Institution

Dept. of Electr. Eng., Minnesota Univ., Minneapolis, MN, USA

fYear

1992

fDate

1-5 June 1992

Firstpage

271

Abstract

Multiple negative resistance bands are predicted at frequencies beyond f/sub max/ in the conventional mesa-type emitter-up AlGaAs-GaAs HBTs (heterojunction bipolar transistors) with careful design and reduced parasitics. Thus, HBT power gain may be obtained in these frequency bands with the negative resistance even above f/sub max/. To obtain the usable transit time effect with large negative resistance, the increase of collector transit time is preferable to increasing base transit time. Therefore, for transit time HBTs, the base should be designed to be as thin as possible, and the collector should be thick enough to obtain the large transit time in the frequency range of interest, while keeping parasitics small.<>

Keywords

III-V semiconductors; aluminium compounds; equivalent circuits; gallium arsenide; heterojunction bipolar transistors; negative resistance; semiconductor device models; solid-state microwave devices; AlGaAs-GaAs; HBT; HF characteristics; emitter-up device; heterojunction bipolar transistors; high-frequency characteristics; mesa-type; multiple negative resistance bands; power gain; small-signal circuit model; transit time effect; Conductivity; Contact resistance; Delay effects; Electric resistance; Electron emission; Equivalent circuits; Frequency; Gallium arsenide; Heterojunction bipolar transistors; Parasitic capacitance;

fLanguage

English

Publisher

ieee

Conference_Titel

Microwave Symposium Digest, 1992., IEEE MTT-S International

Conference_Location

Albuquerque, NM, USA

ISSN

0149-645X

Print_ISBN

0-7803-0611-2

Type

conf

DOI

10.1109/MWSYM.1992.187964

Filename

187964