Reduction in reverse leakage current of diamond vertical Schottky barrier diode using SiNX field plate structure

Abstract

Diamond vertical Schottky barrier diodes (SBDs) with SiNX field-plate (FP) structure has been investigated. Ti/Au and Zr/Ni/Au metal stacks are used as ohmic and Schottky metal, respectively. The forward current density of SBDs with and without FP are 1600 and 3300 A/cm2 at −10 V, respectively. The depletion layer’s thickness and net doping concentration are 380 nm and 1.4 × 1016 cm−3, respectively, as extracted from the capacitance-voltage measurement. The reverse leakage current of SBDs with and without FP are 1.8 × 10−6 and 6.3 A/cm2 at 100 V, respectively, indicating that the FP technique can significantly suppress reverse leakage current at the Schottky junction edge.