Experimental study of burnout of microwave bipolar transistors under action of a series of electric pulses

Burnout of silicon transistors under the action of a periodic train of electric pulses is experimentally studied. A numerical model and a more physically demonstrative analytical model of the pulse-to-pulse heat accumulation are in qualitative and, to a certain extent, quantitative agreement with the measured results. It is demonstrated that catastrophic failure takes place at a melting point of silicon but additional heat is needed for melting of low-temperature eutectics.