Investigation of Thermal Properties of β-Ga₂O₃Nanomembranes on Diamond Heterostructure Using Raman Thermometry

The β-Ga2O3 nanomembrane (NM)/diamond heterostructure is one of the promising ultra-wide bandgap heterostructures that offers numerous complementary advantages from both materials. In this work, we have investigated the thermal properties of the β-Ga2O3 NM/diamond heterostructure with three different thicknesses of β-Ga2O3 nanomembranes (NMs), namely 100 nm, 1000 nm, and 4000 nm thick β-Ga2O3 NMs using Raman thermometry. The thermal property-temperature relationships of these β-Ga2O3 NM/diamond heterostructures, such as thermal conductivity and interfacial thermal boundary conductance were determined under different temperature conditions (from 100 K to 500 K with a 40 K interval). The result provides benchmark knowledge about the thermal conductivity of β-Ga2O3 NMs over a wide temperature range for the design of novel β-Ga2O3-based power electronics and optoelectronics.