Thermal Evaluation of Chip-Scale Packaged Gallium Nitride Transistors

With power converters demanding higher power density, transistors must be accommodated in an ever-decreasing board space. Beyond gallium nitride (GaN)-based power transistors' ability to improve electrical efficiency, they must also be more thermally efficient. In this paper, we will evaluate the thermal performance of chip-scale packaged enhancement-mode GaN field-effect transistors and compare their in-circuit electrical and thermal performances with state-of-art silicon MOSFETs. This paper will conclude with the proposal of a thermal figure of merit for designers to use as a tool to quickly compare the thermal efficiency of device packaging technologies.