4-kV Quasi-Vertical GaN Schottky Barrier Diode With Reverse p-n Junction Termination

In this paper, we demonstrate high-performance quasi-vertical GaN-on-Sapphire Schottky barrier diodes (SBD) with a reverse GaN p-n junction termination (RPN). The SBD has a current output of 1 kA/cm 2 at V₅=2. 5 V, a low V₎₍ of 0. 66 V ± 0. 017 V, a low R₎₍, ₒ₏ of 1. 4 m cm 2, current ON/OFF ratio of over 10^9 (−3 V~3 V). By introducing the RPN, the breakdown voltage can boost from 459 V to 1419 V, and power figure-of-merit (FOM) can reach 1438 MV/cm 2. It is shown that the presence of the RPN with a suitable anode recess depth can generate an electric field (EF) opposite to the built-in EF at the center of the second top p-n junction, which can decrease the EF peak intensity and make the electric field more uniformly distributed inside the device. Finally, the leakage current of the SBD is inhibited and the breakdown voltage is increased.