Current–voltage–temperature and capacitance–voltage–temperature characteristics of TiW alloy/p-InP Schottky barrier diode

Abstract

We systematically characterize TiW alloy/p-InP Schottky barrier diode using current–voltage (I–V) and capacitance–voltage (C–V) measurements for different temperatures from 300 K to 400 K. The electrical parameters such as barrier height (Φb0) and ideality factor (n) have been obtained from the thermal emission (TE) theory. Φb0 increases and n decreases with the increasing of temperature. The temperature dependency of barrier characteristics is interpreted by TE theory assuming a Gaussian distribution of the barrier heights according to the inhomogeneous model. The mean barrier height Φ¯b0(T=0K)=1.09V and standard deviation σ0 = 135 mV are obtained by plotting Φb0 versus 1/2kT, indicating the Gaussian distribution of the barrier heights. The value of extracted Richardson constant A* is 56.2504 Acm−2 K−2, which is in good agreement with the theoretical value. All these obtained results show that the carrier transport process can be modeled by the TE theory. In addition, the C–V characteristics are analyzed by taking into account series resistance (Rs). The extracted interface states distribution shows the increase of the interface state density from midgap towards the top of the valence band.