Mechanical Stress Dependence of Power Device Electrical Characteristics

Abstract

This paper describes how mechanical stress affects the electrical characteristics of power devices, depending on the surface structure of the device and stress direction. We applied ideal external uni-axial stress to the various power devices, and studied the mechanism by comparing results from experiments and simulations. We found that the stress dependence of the on-state voltage mainly arose from the MOSFET portion of the IGBT. This consideration gives us the important information for designing a power module with higher output density.