Defect-insensitive current–voltage characteristics of Schottky barrier diode formed on heteroepitaxial α-Ga2O3 grown by mist chemical vapor deposition

An n-type α-Ga2O3 layer was grown by mist chemical vapor deposition on a sapphire substrate, and a Ti/α-Ga2O3 Schottky barrier diode was fabricated. Although the α-Ga2O3 layer has a high threading dislocation density (larger than 109 cm−2), the ideality factor of 1.03 was obtained from the forward current–voltage characteristic in the range of 298 K–423 K, indicating the clear thermionic emission transport. The reverse current–voltage characteristic was also investigated, and the leakage current showed good agreement with the theoretical calculation based on the thermionic field emission model without any fitting parameter in the temperature range of 298 K–423 K.