Nuclear Science and Engineering / Volume 191 / Number 1 / July 2018 / Pages 98-103
Technical Paper / dx.doi.org/10.1080/00295639.2018.1450004
For evaluating the SiGe heterojunction bipolar transistors (HBTs) performance during and after gamma-ray irradiation, the characteristics of the direct current (dc) gain of the test samples changed with increasing irradiation dose, and collector current injection levels during 60Co gamma irradiation were measured and analyzed. The experimental results of the typical dc and alternating current (ac) electronic parameters before and after irradiation revealed that the base current Ib, the collector current IC, the dc current gain, and the maximum oscillation frequency fmax exhibited degradation. While other electronic parameters including the cut-off frequency fT, the ac current gain |H21|, and output capacitance CBC did not exhibit any significant change compared with those of pre-irradiation. The degradation mechanisms of the typical dc and ac parameters measured in this work were primarily analyzed. The tested results of SiGe HBTs offered some reference data for evaluating the behavior of the test type of device operated in an ionizing radiation environment.