Gaussian distribution of inhomogeneous nickel–vanadium Schottky interface on silicon (100)

Abstract

This study presents the characterization of the nickel–vanadium (NiV) Schottky diode on n-type silicon (Si) in the temperature range 75 K–300 K. The experimental current–voltage (I–V) measurements are first analyzed by using the thermionic emission (TE) theory. For this purpose, the vertical optimization method is used to find the values of the TE parameters, i.e. the values of the ideality factor, barrier height, and series resistance. It is found that these parameters exhibit strong temperature dependence, i.e. an increase of the ideality factor and a decrease of the barrier height and the series resistance when the temperature decreases, which is due to inhomogeneities at the Schottky interface. Therefore, we employ Werner’s model under the assumption of a Gaussian distribution to analyze the temperature dependence of the TE parameters. The mean and standard deviation of the barrier height are obtained as and , respectively. In addition, we show that the apparent barrier height and apparent ideality factor are in accordance with Werner’s model. Furthermore, we use the modified Richardson plot to find the value of the Richardson constant. The obtained value of the latter is A cm−2 K−2 and is very close to the theoretical value of 112 A cm−2 K−2 of n-type Si. Finally, we investigate the temperature dependence of the ideality factor and show the validity of the T0-effect for the NiV/Si Schottky diode.