Investigation on the performance dependence of proton radiated SiGe HBTs with emitter area and temperature

The DC and AC performances of proton radiated Silicon-Germanium (SiGe) Heterojunction Bipolar Transistors (HBTs) with different emitter areas at liquid nitrogen temperature (77 K), room temperature and heating hotplate (393 K) were presented in this work. Performance dependence on the emitter area and temperature was investigated. Results showed that SiGe HBTs with a large emitter area had more damage by proton radiation. Furthermore, the SiGe HBTs showed better tolerance to proton radiation at extreme temperatures than at room temperature. To reveal the underlying mechanism, the radiated SiGe HBTs were modeled based on the device structure and parameters. The electron density, Shockley–Read–Hall (SRH) recombination and carrier mobility were extracted from the device model and demonstrated to have major impacts on the performance dependence of the radiated SiGe HBTs. The results provide useful guidance for the application of SiGe HBTs at extreme environments.