Experimental investigation of electron transport properties of (Mo/Au)/Al0.26Ga0.74N/GaN/Si Schottky barrier diodes

AlGaN/GaN/Si Schottky barrier diodes have been investigated using the current-voltage measurements in the wide temperature range of 125 - 500K. Measurements were performed an increase in barrier height and a decrease in the ideality factor with increasing temperature. This is attribued to barrier inhomogeneities by assuming a Gaussian distribution of barrier heights. It is also found that the values of series resistance obtained from Cheung's method strongly depend on temperature and decrease with increasing temperature. As is shown, the temperature-dependent current-voltage characteristics of the Schottky barrier diodes have been explained by invoking a double Gaussian distribution at the metal/semiconductor interface. Finally, the thermionic field emission is considered as the phenomena responsible for the excess currents observed in Schottky barriers.