Schottky barrier heights of InxAl1−xAs (0≤x≤0.35) epilayers on GaAs

The electrical characteristics of Al Schottky diodes on n‐type InxAl1−xAs (0≤x≤0.35) were investigated in detail by current‐voltage and capacitance‐voltage measurements. These high‐quality InAlAs epilayers were grown on GaAs using step‐graded buffers under proper growth conditions. It was found that the Schottky barrier height of the epilayers increases with Al content as opposed to what was predicted previously. The effect of the interfacial oxide layer on the determination of Schottky barrier height is also presented.