Research on the growth of β-(AlGa)2O3 film and the analysis of electrical characteristics of Ni/Au Schottky contact using Tung's model

Single crystalline β-(AlGa)2O3 epilayer was grown on β-Ga2O3 (010) substrate using pulsed laser deposition. By high resolution X-ray diffraction and X-ray photoelectron spectroscopy measurements, the Al composition was determined to be 11%-13%, somewhat larger than that of target. In addition, Schottky diodes were fabricated on epitaxial β-(Al0.11Ga0.89)2O3 film using Ni/Au as the anode contacts and the electrical characteristics were performed in the temperature range from 300 K to 573 K. From the forward I-V curves, the Φb and n were obtained and they are both strongly dependent on the temperature, which was attributed to the inhomogeneous Schottky barrier height distribution. According to the Tung's model, the mean barrier height of 1.38 eV and A* of 46.52 Acm−2K−2 are extracted by the modified Richardson plot.