The effects of proton irradiation on the RF performance of SiGeHBTs

The effects of proton irradiation on the RF performance of SiGe Heterojunct ion Bipolar Transistors (HBTs) are reported in this paper. Frequency respon se and broadband noise properties are investigated in SiGe HBTs for proton fluences up to 5x10(13) p/cm(2). The current gain in the radio frequency (R F) bias region and the cutoff frequency (f(T)) show little degradation at e ven extreme proton fluence (realistic space fluences are 1-5x10(11) p/cm(2) ). The slight degradation of NFmin is due to the irradiation-induced increa se in the total emitter and base resistance. The associated available gain GA,assoc at noise matching is 20.2 dB at f=2 GHz and I-C=2.6 mA for a proto n fluence of 5x10(13) p/cm(2). These results suggest that space-borne RF ci rcuit applications of SiGe HBTs should be robust to proton irradiation.