Silicon Carbide (SiC) MOSFETs offer excellent properties as switches in power converters. However, the package of the device is an issue that prevents utilizing the advantages of SiC, as for instance fast switching speed. The packages of currently available SiC devices are the same as those previously used for silicon devices with moderate electrical and thermal characteristics resulting in accelerated aging and reliability issues. Furthermore, the parasitic inductance caused by the package, limits the switching time and operating frequency. By excluding the package, the parasitic inductances will be eliminated to a large extent. In this study, the procedure of manufacturing a half-bridge planar power module, using four SiC MOSFET bare dies and PCB, is described. According to simulations in ANSYS-Q3D, the parasitic inductance Lstray of the structureis approximately 96% lower than most commercial half-bridge modules. It is also shown that double-side cooling can bee mployed for the proposed module if substrates with low thermal resistance are used.
QC 20180209