Lifetime analysis of power modules with new packaging technologies

Abstract

Several novel packaging technologies for power modules have been recently introduced to meet the future requirements of higher reliability and temperature stability. Using copper wire bonds for the top-side interconnect and silver sintered or diffusion soldered die attach layers led to a significant increase of lifetime. It was subsequently shown that the power cycling lifetime of modules without a baseplate is mainly limited by the substrate metallization, while modules employing a baseplate and a substrate-to-baseplate solder interconnect fail due to degradation within the solder layer. The investigations in this paper continue with the description and systematization of degradation effects in new interconnect technologies of power modules. As a result first lifetime models for modules with and without baseplate are provided. Thereby, accepted lifetime models for standard technologies are adopted to the degradation patterns of the new technologies.