The further investigation of N-doped β-Ga2O3 thin films with native defects for Schottky-barrier diode

The structural, electronic and optical properties of β-Ga2O3 thin films with different N ion concentrations are investigated. With N concentrations increasing, the crystallization degrades and even polycrystalline appears. After Ar annealing treatment, the crystallization of N-doped β-Ga2O3 thin films improved owing to recovery of the implantation-damaged crystals. The N-doped Ga2O3 thin films were used to construct vertical Schottky diodes comprising Ga2O3:N/n-Ga2O3. The net carrier concentrations of these devices degrade one-two orders due to the compensation effect of more N implantation, which suggests that hole could be mobile although N is a deep acceptor dopant. The phenomenon could be explained by the decrease of the ionization energy of N dopant due to the complex defects NGa2O3VO (N-doped β-Ga2O3 with O vacancy) and NGa2O3VGa (N-doped β-Ga2O3 with Ga vacancy). Thus, the development of N ion implantation for β-Ga2O3 has its potential opportunity for β-Ga2O3 power devices.