Extreme reduction of on-resistance in vertical GaN p-n diodes by low dislocation density and high carrier concentration GaN wafers fabricated using oxide vapor phase epitaxy method

Abstract

Low dislocation density and low-resistance GaN wafers are in high demand for improving the performance of vertical GaN power devices. Recently, GaN wafers with the dislocation density of 8.8 × 104 cm-2 and the resistivity of 7.8 × 10-4 Ω cm, were fabricated using oxide vapor phase epitaxy (OVPE). In this study, GaN p-n diodes on GaN wafers prepared by the OVPE method were evaluated for verifying their suitability as vertical GaN power devices. An extremely low-differential specific on-resistance of 0.08 mΩ cm2 and a high breakdown voltage of 1.8 kV were obtained from forward and reverse I-V measurements.