Device topological thermal management of β-Ga2O3 Schottky barrier diodes*

Abstract

The ultra-wide bandgap semiconductor β gallium oxide (β-Ga2O3) gives promise to low conduction loss and high power for electronic devices. However, due to the natural poor thermal conductivity of β-Ga2O3, their power devices suffer from serious self-heating effect. To overcome this problem, we emphasize on the effect of device structure on peak temperature in β-Ga2O3 Schottky barrier diodes (SBDs) using TCAD simulation and experiment. The SBD topologies including crystal orientation of β-Ga2O3, work function of Schottky metal, anode area, and thickness, were simulated in TCAD, showing that the thickness of β-Ga2O3 plays a key role in reducing the peak temperature of diodes. Hence, we fabricated β-Ga2O3 SBDs with three different thickness epitaxial layers and five different thickness substrates. The surface temperature of the diodes was measured using an infrared thermal imaging camera. The experimental results are consistent with the simulation results. Thus, our results provide a new thermal management strategy for high power β-Ga2O3 diode.