Title :
A cryogenic GaAs HBT microwave amplifier and its application to a superconductor digital IC
Author :
Kobayashi, K.W. ; Kobayashi, J.H. ; Leung, M. ; Oki, A.K. ; Matloubian, M. ; Chan, S. ; Streit, D.C.
Author_Institution :
TRW, Redondo Beach, CA, USA
Abstract :
The first microwave GaAs HBT (heterojunction bipolar transistor) amplifier results at 4.2 K are benchmarked. The amplifier nominal gain is 6 dB and is measured from 130 MHz to 10 GHz at fixture temperatures of 295 K, 77 K, and 4.2 K. The maximum gain variation over temperature was found to be about 2 dB. Maximum gain occurred at temperatures around 50-85 K, whereas at 4.2 K the gain seemed to drop slightly from that at room temperature. Only slight RF evidence of carrier freeze-out was observed at a fixture temperature of 4.2 K, although HBT junction temperatures are estimated to be around 25-30 K. This chip was integrated as a buffer amplifier with a high-temperature-superconductor digital logic gate and has shown functionality up to 320 MHz.<>
Keywords :
III-V semiconductors; digital integrated circuits; gallium arsenide; heterojunction bipolar transistors; microwave amplifiers; microwave integrated circuits; superconducting integrated circuits; 130 MHz to 10 GHz; 295 K; 4.2 K; 6 dB; 77 K; amplifier nominal gain; buffer amplifier; carrier freeze-out; cryogenic GaAs HBT microwave amplifier; gain variation; high-temperature-superconductor digital logic gate; superconductor digital IC; Application specific integrated circuits; Cryogenics; Digital integrated circuits; Gallium arsenide; Heterojunction bipolar transistors; Microwave amplifiers; Microwave integrated circuits; Superconducting integrated circuits; Superconducting microwave devices; Temperature;
Conference_Titel :
Microwave Symposium Digest, 1993., IEEE MTT-S International
Conference_Location :
Atlanta, GA, USA
Print_ISBN :
0-7803-1209-0
DOI :
10.1109/MWSYM.1993.276799