Packaging of high voltage power semiconductor modules

As the breakdown voltage capability of power semiconductor devices increases, new methods have become necessary to facilitate these devices in the packaging of high voltage power semiconductor modules. Silicon carbide has been hailed as one of the successors to silicon power semiconductor devices due to its wide bandgap, low on-state resistance, and high operating temperature, among others. As the breakdown voltage of the next generation of silicon carbide devices pass the 10kV threshold, new packaging schemes must be utilized to take full advantage of these devices. This thesis investigates a direct attachment packaging scheme and the use of benzocyclobutene (BCB) as a substrate passivation layer for the high-voltage silicon carbide power module. A discussion on the physics of breakdown through gasses and solids is presented as well as simulations for determining electric field strength in a high voltage module. The processing steps required to coat a direct bond copper substrate with BCB are detailed in addition to materials selection and fabrication procedures necessary to construct the final high voltage module. Final testing resulted in a module capable of blocking up to 6.3 kV without failure.