The effects of gamma irradiation on GaAs HBT

The effects of gamma irradiation on Gallium-Arsenide (GaAs) Heterojunction Bipolar Transistor (HBT) is reported. DC and Radio Frequency (RF) performance are investigated for gamma doses up to 7 Mrad(Si). After 7Mrad(Si) gamma irradiation, an increase of base current (l_b) is observed, the change is thought to be mainly due to the reduction of the effective minority carrier lifetime (τ) in the n-type emitter. Besides, the cutoff frequency (f_T) decreases, which is caused by the decrease of the electron mobility (μ_n) in the base and the collector-base space charge region.