An initial consideration of silicon carbide devices in pressure-packages

Fast switching SiC Schottky diodes are known to exhibit significant output oscillations and electromagnetic emissions in the presence of parasitic inductance from the package/module connections. Furthermore, solder pad delamination and wirebond lift-off are common failure modes in high temperature applications. To this end, pressure packages, which obviate the need for wire-bonds and solder/die attach, have been developed for high power applications where reliability is critical like thyristor valves in HVDC line commutated converters. In this paper, SiC Schottky diodes in pressure-packages (press-pack) have been designed, developed and tested. The electrothermal properties of the SiC diode in press-pack have been tested as a function of the clamping force using different thermal contacts, namely molybdenum and Aluminum Graphite. Finite Element Simulations have been used to support the analysis.