Enhancement of heat dissipation in β-GaO Schottky diodes through Cu-filled thermal vias: experimental and simulation investigations

β-Ga 2 O 3 with ultrahigh bandgap has emerged as a promising material for next-generation power semiconductors owing to its superior electrical properties. However, its low-thermal conductivity presents challenges for heat dissipation under high-power conditions. In this study, we propose and investigate an efficient device structure for β-Ga 2 O 3 devices featuring Cu-filled thermal through-vias to facilitate direct heat dissipation from the channel to the exterior parts. Through-vias were formed in the β-Ga 2 O 3 substrate using ultraviolet laser drilling and subsequently filled with highly thermally conductive Cu using electroplating. The thermal performance of the Cu-filled through-vias was assessed by applying low (1.2 W mm −3 ) and high (5.7 W mm −3 ) power settings to the device and analyzing the surface temperature with a high-resolution thermal imaging camera. Finite element simulations were employed to verify the heat dissipation improvement achieved by the thermal vias. Experimental results demonstrate that at 5.7 W mm −3 , the temperature increase is suppressed by approximately 21%, and the time to reach peak temperature steady-state decreases by approximately 90% when a thermal through-via is used. The simulation results demonstrate a temperature reduction effect of approximately 33%, which is more effective than the experimental observations. Additional simulations indicated that two or more thermal vias with diameters