Characteristics of Ferromagnetic Schottky Diodes on Heavily n-Doped GaN Semiconductor

We have investigated ferromagnetic (Fe, Co and Ni) Schottky diodes on heavily n-doped GaN. We have grown, fabricated, characterized, and analyzed these diodes to extract junction parameters and ascertain transport mechanism. We have observed simple thermionic emission failed to explain the experimental characteristics. Thermionic emission with Gaussian distribution for barrier inhomogeneity can explain the data for high bias voltages. It is observed other transport mechanisms at low bias voltages are important. Direct tunneling have been found to contribute significantly for Fe/GaN Schottky diodes. However, trap assisted tunneling is found to be dominant for Co/GaN and Ni/GaN devices under same condition.