Hybrid BaTiO3/SiNx/AlGaN/GaN lateral Schottky barrier diodes with low turn-on and high breakdown performance

Abstract

In this Letter, we demonstrate hybrid GaN lateral Schottky barrier diodes with enhanced breakdown characteristics and a low turn-on voltage. These diodes incorporate a lateral Schottky barrier in combination with a high permittivity material beneath the field plate, enabling high average breakdown fields and a low turn-on voltage. Average electric fields up to 2.38 MV/cm were achieved for devices with an anode-cathode spacing of 4 μm, while maintaining with a turn-on voltage of 0.48 V. In contrast, SiNx/AlGaN/GaN control lateral Schottky diodes displayed an average breakdown field of ∼0.7 MV/cm for devices with similar dimensions with a turn-on voltage of 0.46 V. The use of a high-permittivity dielectric can more effectively utilize the high breakdown fields in wide bandgap materials by proper management of the electric field. This demonstration provides an innovative way to integrate high-permittivity materials with GaN lateral devices for improved breakdown and resistance characteristics.