Numerical study of Schottky diode based on single GaN NW on Si

Numerical modelling of Schottky diode formed by single GaN nanowire on Si substrate was performed. Two metals, namely, gold and platinum forming the Schottky barrier were considered. The potential barrier height was calculated taking into account occurrence of image force as well as Fermi level pinning at metal/semiconductor interface. Volt-ampere characteristics were obtained for different NW doping levels considering Wentzel–Kramers–Brillouin tunneling model. Cutoff frequencies are evaluated from current-time relaxation curves for different NW lengths and doping levels. It is shown that such diode structure demonstrates high-speed performance with cutoff frequency in the range from 0.1 to 0.9 THz for both studied metals.