Finding solder cavities in high power modules with temperaturesensitive parameters

Abstract:
The solder layers in power semiconductors are thin and unremarkable, yet essential for function and lifetime of a power module. They conduct the current, transmit the losses to the baseplate and cooler, and have to withstand mechanical tension. Therefore, the quality and the condition of the solder layers are important. Within this paper, several temperature-sensitive parameters are analyzed to determine solder cavities. For this, measurements are made to investigate the effect of solder cavity size on the electric parameters. Moreover, a simulation model is built to test different heating mechanisms and the resulting effect on the temperature-sensitive parameter.