Lightly doped emitter HBT for low-power circuits
- Resource Type
- Periodical
- Authors
- Chang, C.E.; Chen, P.F.; Asbeck, P.M.; Tran, L.T.; Streit, D.C.; Oki, A.K.
- Source
- IEEE Microwave and Guided Wave Letters IEEE Microw. Guid. Wave Lett. Microwave and Guided Wave Letters, IEEE. 7(11):377-379 Nov, 1997
- Subject
- Fields, Waves and Electromagnetics
Heterojunction bipolar transistors
Capacitance
Current density
Microwave devices
Digital circuits
Gallium arsenide
Power dissipation
Space technology
Doping
Logic circuits
- Language
- ISSN
- 1051-8207
1558-2329
We report an approach to reduce the base-emitter capacitance in AlGaAs-GaAs heterojunction bipolar transistors (HBT's) by adding a lightly doped emitter (LDE) region together with appropriate planar (/spl delta/) doping region to a conventional base-emitter junction. This improves both the f/sub t/ and /spl beta/ for low collector current density (J/sub c/) operation while preserving the high peak f/sub t/ at high J/sub c/. When applied to a current mode logic 128/129 programmable prescaler, the LDE HBT results in a reduction in power dissipation and improved bandwidth without any circuit modifications.