Over 3.5 kV (011) β-Ga 2 O 3 Schottky Barrier Diode and First Demonstration of 4.7 kV NiO-based (011) β-Ga 2 O 3 Heterojunction Diode

The superior material properties of β-Ga2O3make it a promising candidate for high-voltage applications. High quality epi-layers are essential for power devices to enhance the breakdown voltage (BV). However, the widely used (001) β-Ga2O3epi-layer encounters challenges in increasing thickness and reducing carrier concentration, which limits the further improvement of the BV. Importantly, the (011) β-Ga2O3epi-layer does not suffer from these bottlenecks. In this work, we compared the characteristics of Schottky barrier diodes (SBDs) based on (011) and (001) epi-layers. Owing to the fully depleted epi-layer, the BV of (011) SBD without termination reached 1785 V, which is significantly higher than that of (001) SBD. Furthermore, we demonstrated the first NiO-based heterojunction diode (HJD) on (011) β-Ga2O3epi-layer. By utilizing a 3-layers junction termination extension structure, the BV of SBD and HJD improved to 3505 V and 4720 V respectively, confirming the superiority of (011) epi-layer in constructing high-voltage devices.