Date of Graduation


Document Type


Degree Name

Doctor of Philosophy in Engineering (PhD)

Degree Level



Electrical Engineering


H. Alan Mantooth

Committee Member

Zhong Chen

Second Committee Member

Yarui Peng

Third Committee Member

Morgan Ware


Compact Modeling, Cryogenic, Gallium Nitride, HEMT, Power Electronics, Semiconductor


Since power converters shape a wide range of power electronic applications, the 'heart' of these conversions, such as solid-state switches, is crucial for achieving higher power density, lower loss, and higher efficiency operations. Although the limitations imposed by silicon-based power devices have been reduced by introducing novel devices such as IGBTs and super junction MOSFETs to allow for broader applications, solutions beyond silicon have presented a continuous challenge to the device engineers. Driving these converters at a higher switching frequency allows for higher power density. However, to support a higher frequency and operating temperature, superior materials, e.g., wide bandgap materials, are also needed. Two such materials, namely silicon carbide (SiC) and gallium nitride (GaN), thanks to their excellent material properties like higher mobility, higher breakdown electric field, and lower leakage, are paving the way to improved efficiency and high power density with broader functionality. Although SiC plays a vital role in a wider range of power electronics applications, the use of SiC outside of standard operation regions, e.g., cryogenic temperature (

Available for download on Monday, February 17, 2025