Hybrid BaTiO3/SiNx/AlGaN/GaN lateral Schottky barrier diodes with low turn-on and high breakdown performance
Mohammad Wahidur Rahman, Hareesh Chandrasekar, Towhidur Razzak, Hyunsoo Lee, Siddharth Rajan
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.