Thermal properties of ultrawide-bandgap semiconductors towards thermal managing of high-power electronic devices

The research project is focused on the thermal properties of ultrawide-bandgap semiconductors AlGaN, ScAlN, YAlN, and beta-(AlGa)2O3.

Due to their high breakdown electric field, these materials are very promising for high-power electronics and have a potential to over-perform SiC- and GaN-based devices.

The performance of power electronic devices, which are driven at high voltages and high current densities, is greatly limited by the removal of the heat generated during the operation.

Therefore, an efficient heat dissipation is necessary to maintain low device temperature and achieving a high level of stability and reliability.

The heat dissipation depends on both the thermal conductivity of the constituent materials and the thermal boundary resistance (TBR) at the interfaces in the device structures. We will grow and examine epitaxial layers and hetero-structures based of ternary alloys.

The thermal conductivity and the TBR at different interfaces will be measured by transient thermoreflectance in a temperature range of 80-500 K.

For data analysis, appropriate models which account for the phonon scattering due to the lattice anharmonicity, intrinsic and extrinsic defects, alloy-disorder, and layer boundaries, will be developed.

The obtained results are expected to provide a deeper understandings of the thermal properties of the ultrawide-bandgap semiconductors, and thus to facilitate the thermal management of next-generation high-power electronic devices.