| Abstract |
When a power electronic system fails during the development phase or in the field, it is very difficult to know why in order to avoid such event in the future. By the observation of the silicon die, by experience and with the collaboration of the user it is, most of the time, possible to know why the power semiconductor has failed. The main reasons of the failure could be either from the system itself: Overvoltage, overcurrent, thermal runaway, thermal fatigue, infririgement of safe operating areas, electrostatic discharge, or from the power semiconductor device itself: early failure due to a wrong assembly procedure. By the knowledge of the physical phenomena inside of the silicon crystal and the main overstresses given by each type of application and by a long experience and simulations, it is possible to determine the main reason of the failure. A picture of a failed die by each type of stress will be given to help the electrical engineer in his research of a more reliable system. |
