Avalanche capability of today´s power semiconductors

Power semiconductors are used to switch high currents in fractions of a second and therefore belong inherently to a world of voltage spikes. To avoid unnecessary breakdown voltage guardbands, new generations of semiconductors are now avalanche rugged and characterized in avalanche energy. This characterization is often far from application conditions and thus quite useless to the designer. It is easy to verify that an energy rating is not the best approach to a ruggedness quantification because of avalanche energy fluctuations with test conditions. A physical and thermal analysis of the failure mechanisms leads to a new characterization method generating easy-to-use data for safe designs. The short-term avalanche capability is discussed with an insight of the different technologies developed to meet these new ruggedness requirements