电子辐照对GaAs HBT残余电压与饱和电压的影响

研究了GaAs HBT高能电子(～1MeV)辐照的总剂量效应。结果表明,电子辐照后GaAs HBT的基极电流增大,辐照损伤程度随辐照总剂量增加而增加,这和其他研究观察到的现象相同。所不同的是,实验中发现随辐照剂量增大器件集电极饱和电压、残余电压均增大。因此认为,高能电子辐照造成的位移损伤在GaAs HBT集电区和BC结内诱生的大量复合中心使集电极串联电阻增大,以及BE、BC结内形成的复合中心俘获结内载流子使载流子浓度降低造成BE、BC结自建电势差下降是集电极饱和电压和残余电压增加的主要原因。

Study on Voffset and Vsat Shift of GaAs Heterojunction Bipolar Transistors under Electron Irradiation

The total dose effect of high energy(～1 MeV)electron irradiation on the DC characteristic of GaAs single HBT was investigated. It was shown that the base current and irradiation-introduced degradation of GaAs HBT increased with the total dose based on our experimental results which is same with the phenomena observed by other researches. An significant effect of increase in collector-emitter saturation voltage and offset voltage was observed after irradiation. The shift of collector-emitter saturation voltage and offset voltage is due to the irradiation-introduced recombination centers in collector region and base-collector junction region. These recombination centers response for collector series resistance. In the other hand,built-in potential decrease in the emitter-base junction and base-collector junction is due to capturing carrier by recombination centers,which is an are other reason for the shift.