LTCC Embedding of SiC Power Devices for High Temperature Applications over 400 °C

Abstract

This paper encompasses a novel packaging concept based on the embedding of semiconductor devices in Low Temperature Cofired Ceramic (LTCC) multilayer substrates. The wide-bandgap power semiconductor made out of silicon carbide (SiC) is embedded within the co-firing process of the LTCC at around 750 to 850 °C. Filled vias and inlays, realized in the same process, form the electrical interconnection and heat dissipation. This approach combines high-temperature stability over 400 °C junction temperature, compactness, and 3D integration ability into one concept to fulfill all advantages of SiC power semiconductors and other future wide bandgap devices. Moreover, the package design aims for hermetical sealing and harsh environment applications. Various geometric concepts for LTCC pre-packages are developed to investigate the thermal behavior. Two of the ideas could improve the thermal resistance up to 45 % compared to the state of the art power modules. Afterward, complete power modules were designed. In the end, electrical simulations have been executed to analyze the parasitic inductances and the different concepts are discussed.