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

•Diamond vertical SBD with SiNX FP structure has been investigated.•Diamond SBDs with and without FP showed good rectification characteristics.•Reverse current-voltage characteristics showed significant reduction of leakage current of SBD with FP. 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.