Carrier transport mechanism of GaN vertical Schottky barrier diodes with p-GaN termination

This paper investigates GaN vertical Schottky barrier diodes(SBDs) with p-GaN termination structure. The forward and reverse electrical characteristics of the two devices, namely SBDs with TiN/Au and Ni/Au as anode metals,are systematically investigated, and carrier transport models are established for both devices. The SBD with TiN/Au anode follows the thermionic emission model for forward conduction, while its reverse leakage conforms to a combined model of thermionic emission, Poole Frenkel emission, and trap assisted tunneling. For the SBD with Ni/Au anode, forward conduction is governed by thermionic emission and trap assisted tunneling, and reverse leakage follows a combined model of trap assisted tunneling and phonon assisted tunneling.