Mo/GaAs Schottky barriers prepared by d.c. sputtering

Mo/GaAs Schottky barriers have been prepared by d.c. sputtering, for different values of the sputtering voltage. Current-voltage and capacitance-voltage measurements show that these barriers can have very good properties (near one ideality factor, very low inverse saturation current) if suitable preparation conditions are chosen. A detailed study of the current-voltage characteristics as a function of the temperature allows us to analyse the carrier transport mechanisms and to correlate them to the preparation conditions. The experimental results show that the behaviour of the Mo/GaAs Schottky barriers, prepared by d.c. sputtering, can be successfully explained on the basis of the unified defect model proposed for the GaAs schottky barriers.