Conditions of temperature and time instability occurrence of reverse-biased semiconductor power devices

An investigation of the boundary states of power semiconductor devices is important with respect to their function reliability. Focus of this article is based on the evaluation of transient temperature increasing of pn-junction under its reverse bias. An influence of positive feedback (heating by some reverse current) is considered on time stability of this reverse current at constant reverse voltage. The temperature is determined which is limiting transiently the reliable function of devices. The problem is solved by two ways. First of them is based on a physical model design describing the heat generation and conduction in semiconductor structure. The second way uses electrical circuit simulation for study of the same structure. Conclusions of both models are applied to collection of experimental data.