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Abstract: NPN RF power transistors were irradiated with 140MeV Si10+ ions, 100MeV F8+ ions, 50MeV Li3+ ions and Co-60 gamma radiation in the dose range from 100krad to 100Mrad. The transistor characteristics are studied before and after irradiation from which the parameters such as Gummel characteristics, excess base current (ΔI B = I Bpost − I Bpre), dc current gain (h FE), transconductance (g m) and collector-saturation current (I CSat) are determined. The degradation observed in the electrical characteristics is almost the same for different types of ion irradiated NPN RF power transistors with similar total doses although there is a large difference in the linear energy transfer (LET) of the ions. Further, it was observed more degradation in DC I–V characteristics of ion irradiated devices than the Co-60 gamma irradiated devices for higher doses. [Copyright &y& Elsevier]

Abstract: N-channel depletion MOSFETs were irradiated with 140MeV Si10+ ions, 100MeV F8+ ions and 48MeV Li3+ ions in the dose range from 100krad to 100Mrad. The MOSFET parameters such as threshold voltage (V TH), transconductance (g m) and mobility of carriers (μ) were determined by systematically studying the I–V characteristics before and after irradiation. The ion irradiated results were compared with Co-60 gamma irradiated results in the same dose range. The degradation in V TH, g m and μ was found to be more for the devices irradiated with Co-60 gamma radiation than that irradiated with swift heavy ions. [Copyright &y& Elsevier]

N-channel depletion MOSFETs were irradiated with 4 MeV Proton and Co-60 gamma radiation in the dose range of 100 krad(Si) to 100 Mrad(Si). The electrical characteristics of MOSFET such as threshold voltage ( V th ), density of interface trapped charges (Δ N it ), density of oxide trapped charges (Δ N ot ), transconductance ( g m ), mobility ( μ ), leakage current ( I L ) and drain saturation current ( I D Sat ) were studied as a function of dose. A considerable increase in Δ N it and Δ N ot and decrease in V th, g m , μ , and I D Sat was observed after irradiation. The results of 4 MeV Proton irradiation were compared with that of Co-60 gamma radiation and it is found that the degradation is more for the devices irradiated with 4 MeV Protons when compared with the Co-60 gamma radiation. This indicates that Protons induce more trapped charges in the field oxide region when compared to the gamma radiation. [ABSTRACT FROM AUTHOR]

Abstract: We have investigated the effects of 50MeV lithium ion irradiation on the DC electrical characteristics of first-generation silicon–germanium heterojunction bipolar transistors (50GHz SiGe HBTs) in the dose range of 600krad to 100Mrad. The results of 50MeV Li3+ ion irradiation on the SiGe HBTs are compared with 63MeV proton and Co-60 gamma irradiation results in the same dose range in order to understand the damage induced by different LET species. The radiation response of emitter–base (EB) spacer oxide and shallow trench isolation (STI) oxide to different irradiation types are discussed in this paper. We have also focused on the efficacy in the application of a Pelletron accelerator to study total dose irradiation studies in SiGe HBTs. [Copyright &y& Elsevier]

Abstract: Third generation 200GHz silicon–germanium Heterojunction Bipolar Transistors (Si–Ge HBTs) were irradiated with high dose Co-60 gamma radiation up to 100Mrad. Pre-radiation and post-radiation DC figures of merits were used to quantify the radiation tolerance of the different geometry devices. The different electrical characteristics like Gummel measurements, excess base current, current gain, transconductance, neutral base recombination, avalanche multiplication of carriers and output characteristics were studied for different doses from 100krad to 100Mrad of total doses. The Si–Ge HBTs showed robust ionizing radiation tolerance up to a total dose of 100Mrad. [ABSTRACT FROM AUTHOR]