Simultaneous analysis of current-voltage and capacitance-voltage characteristics of metal-insulator-semiconductor diodes with a high mid-gap trap density

Abstract

The effect of Zn doping concentration on the current transport in Au MIS contacts on In0.21Ga0.79As layers grown on highly doped GaAs substrates is studied using an improved method to simultaneously analyze the reverse current-voltage and high frequency capacitance-voltage characteristics of an MIS diode. Based on the numerical solutions of the Poisson's and continuity equations, the method reveal that Zn inhibits the formation of the native oxide at the surface of the In0.21Ga0.79As epilayers. The barrier height at zero bias at room temperature is independent of the Zn doping concentration.