Over 2 GW/cm2 low-conduction loss Ga2O3 vertical SBD with self-aligned field plate and mesa termination

Abstract

In this Letter, a Ga2O3 vertical Schottky barrier diode (SBD) with self-aligned field plate and mesa termination is fabricated and studied. The combination of field plate and mesa termination can effectively make the electric field distribution uniform in the termination, and thus the proposed SBD features high breakdown voltage (BV). Moreover, to eliminate alignment deviation and simplify the fabrication process, a self-aligned etching process is developed. The experimental results show that a low specific on-resistance of 4.405 mΩ·cm2 and a high BV of 3113 V can be simultaneously derived on the proposed SBD, yielding a high power figure of merit of 2.2 GW/cm2. Meanwhile, a considerably low forward voltage of 1.53 V at 100 A/cm2 is also achieved, demonstrating the low conduction loss of the device.