FAILURE ANALYSIS OF POWER TRANSISTORS

This article illustrates a number of types of degradation and material damage found in the microstructures of the component parts of power t ransistors. The various types of damage are clarified with reference t o the results of metallographical investigations which clearly trace t he microstructural changes and damage sustained back to causes such as current or voltage overload, or temperature cycling in service,The th ermomechanical fatigue processes presented show that semiconductor com ponents are subject to damage by long term material degradation.