Anisotropic electrical properties of NiOx /β-Ga2O3 p-n heterojunctions on (2̅01), (001), and (010) crystal orientations

Abstract

NiOx/β-Ga2O3 p-n heterojunctions fabricated on (201 ̅), (001), and (010) β-Ga2O3 substrates show distinctly anisotropic electrical properties. All three devices exhibited excellent rectification 109, and turn-on voltages >2.0 V. The (010) device showed very different turn-on voltage, specific on-resistance, and reverse recovery time compared with (201 ̅) and (001) devices. Moreover, it is calculated that the interface trap state densities for (201 ̅), (001), and (010) plane devices are 4.3 × 1010, 7.4 × 1010, and 1.6 × 1011 eV–1cm–2, respectively. These differences in the NiOx/β-Ga2O3 heterojunctions are attributed to the different atomic configurations, the density of dangling bonds, and interface trap state densities.