For homo-junction Si bipolar transistor operation under common emitter

because of the positive feedback of thermoelectricity

thermal breakdown occurs easily at high collector——emitter voltage and high current

this decreases the safe operation area of transistors.In this paper

due to negative feedback of thermoelectricity

negative resistance characteristics of Si/SiGe/Si double hetero-junction bipolar transistors with heavily doped base at high currents is reported.A new interpretation to this phenomenon is given.This is resulted from Auger recombination in the base and decrease in current gain at high current as temperature increases.This phenomenon has benefit to improve anti-burnout capability of bipolar transitors.The results suggest that Si/SiGe/HBT is suitable for high power applications.