“Second Breakdown” in Transistors

In the paper "Second Breakdown" in Transistors, each of the mechanisms that had been proposed in the literature was examined and shown to be inadequate. A more complete description of the characteristics of second breakdown was given and it was shown that it is a fundamental property of the transistor. On the basis of an observed delay time before the initiation of the breakdown, it was proposed that the phenomenon is related to a thermal mechanism. It was shown that the onset of second breakdown cannot be predicted simply in terms of voltage and current, as had been the practice, but that it is important to characterize second breakdown in terms of the energy dissipated in the transistor. It was also shown that the energy threshold (or delay time) is dependent on other factors such as ambient temperature and the biasing base current of the transistor.