Processes on the target surface under vanadium reactive sputtering in Ar-O2 mixtures

Experimental realization of the hysteresis-free mode of vanadium reactive magnetron sputtering in Ar-O₂ mixtures made it possible to perform detailed measurements of the discharge current-voltage characteristics for the first time. They appeared to be not smooth, as predicted by the existing model of reactive sputtering, but having a kink. The experimental data can be interpreted on the assumption that the target surface is oxidized at a depth not less than two monolayers at low ion current densities.