Title :
Small signal RF performance of AlGaN/GaN heterojunction bipolar transistors
Author :
McCarthy, L.S. ; Smorchkova, I.P. ; Fini, P. ; Rodwell, M.J.W. ; Speck, J. ; DenBaars, S.P. ; Mishra, U.K.
Author_Institution :
Dept. of Electr. & Comput. Eng., California Univ., Santa Barbara, CA, USA
fDate :
1/31/2002 12:00:00 AM
Abstract :
Small signal RF characteristics of an AlGaN/GaN HBT are presented. The devices had a short circuit current gain cutoff frequency of 2 GHz. The roll off of the short-circuit current gain (H21) of the device was less than 20 dB/decade. We propose that this is due to the distributed nature of the base-collector parasitic resistance-capacitance network caused by a high sheet resistance in the base (100 kΩ/□) and high base contact resistances. Finite element small signal equivalent circuit simulations support this explanation
Keywords :
III-V semiconductors; UHF bipolar transistors; aluminium compounds; equivalent circuits; finite element analysis; gallium compounds; heterojunction bipolar transistors; semiconductor device measurement; semiconductor device models; wide band gap semiconductors; 2 GHz; AlGaN-GaN; AlGaN/GaN heterojunction bipolar transistors; HBT; RE characteristics; base; distributed base-collector parasitic resistance-capacitance network; finite element small signal equivalent circuit simulations; high base contact resistances; high sheet resistance; roll off; short circuit current gain cutoff frequency; short-circuit current gain; small signal RF performance;
Journal_Title :
Electronics Letters
DOI :
10.1049/el:20020101
