Effect of sputter voltage on the electrical characteristics of argon ion sputtered n-type GaAs

Epitaxially grown n-type GaAs was sputtered by bombarding it with Ar ions at voltages between 0.5 and 5 kV at a dose of 1013 ions/cm2. The electrical characteristics of the sputtered GaAs were investigated by studying the sputter induced defects using deep level transient spectroscopy (DLTS). The effect of these defects on the electrical characteristics of gold (Au) Schottky barrier diodes (SBDs) was studied by current-voltage (I-V) and capacitance-voltage (C-V) measurements. It was found that the barrier height of the SBDs changed nonmonotonically with sputter voltage, and this could be correlated with the combined effect of sputter induced defects with discrete and continuous energy levels in the GaAs band gap. (orig.)