Gallium oxide (Ga₂O₃) is emerging as a next-generation power semiconductor material due to its excellent electrical properties, including an ultra-wide bandgap of approximately 4.8 eV and a breakdown electric field of about 7 MV/cm. However, its low thermal conductivity of around 0.13 W/cmK presents significant challenges to the performance and reliability of Ga₂O₃- based devices. In this study, we employed the Silvaco TCAD simulator to analyze the thermal and electrical characteristics of Ga₂O₃ Schottky barrier diodes (SBDs) with heat sinks of varying thermal conductivities. The results demonstrate that heat sinks with higher thermal conductivity effectively mitigate the temperature rise in the device, leading to an increase in current density. The limitation in heat dissipation due to parasitic on-state resistance not only affects device performance but also impacts longterm reliability. Therefore, this study contributes to the development of effective thermal management strategies for Ga₂O₃-based power semiconductors.
In this paper, we discussed the effect of field plate dielectric materials such as silicon dioxide (SiO2), aluminum oxide (Al2O3), and hafnium oxide (HfO2) on the breakdown characteristics of β-Ga2O3 Schottky barrier diodes (SBDs). The breakdown voltage (BV) of the SBDs with a field plate was higher than that of SBDs without a field plate. The higher dielectric constant of HfO2 contributed to the superior reduction in electric field concentration at the Schottky junction edge from 5.4 to 2.4 MV/cm. The SBDs with HfO2 field plate showed the highest BV of 720 V, and constant specific on-resistance (Ron,sp) of 5.6 mΩ·㎠, resulting in the highest Baliga’s figure-of-merit (BFOM) of 92.0 MW/㎠. We also investigated the effect of dielectric thickness and field plate length on BV.