Stacked power module with integrated thermal management

Abstract

Current power electronics devices are unable to realize their full capabilities due to the challenges of standard planar packaging including heat dissipation, reliability and parasitic inductance. This work aims to address all of these challenges simultaneously, thus creating a revolutionary approach to power packaging which significantly improves overall capability. The new approach stacks power devices between copper layers with an integrated heat sink. By stacking devices, the module is no longer constrained by the limitations of planar packaging; however it is limited by the ability to remove heat which is solved by integrating heat sinks directly in contact with both the top and bottom of each die. The key-enabling feature of this packaging approach is the multi-functional components (MFCs) which act as electrical, thermal and mechanical attachments concurrently. This co-designed approach aims to eliminate single function components such as wirebonds and heat sinks whose sole purpose is electrical conduction or heat removal, respectively, and replace them with MFCs. This work describes the fabrication of the module and also shows thermal, fluid, and mechanical modeling results. The modeling showed a total package thermal resistivity of 0.25 K-cm2/W. This new power module configuration has the potential to significantly reduce size, weight and cost while improving reliability and performance.