A study on radiation damage of IGBTs by 2-MeV electrons at different irradiation temperatures

摘要

The response of the turn-off time, forward voltage drop and leakage current of IGBT (insulated-gate bipolar transistor) irradiated at different temperatures by 2-MeV electrons for fluences between 10~(13) and 10~(15) e/cm~2, is described. The carrier lifetime, derived from the exponential part of the turn-off current signal, drops from 719 ns before irradiation to 704, 465 and 265 ns, after exposure to a 10~(13), 10~(14) and 10~(15) e/cm~2 fluence, respectively. The forward voltage drop increases from 3.31 V before irradiation to more than 11.0 V for 10~(15) e/cm~2. From the injection current dependence of the lifetime it is shown that the dominant process at high injection changes from Auger recombination before irradiation to Shockley―Read―Hall (SRH) recombination after irradiation. It is finally shown that the degradation of the IGBT electrical parameters decreases with increasing irradiation temperature.