Reduction of copper oxide thin films with hydrogen plasma generated by a dielectric-barrier glow discharge

The reduction behavior of sputtered thin Cu2O films with hydrogen plasma generated by a dielectric-barrier glow discharge was investigated by means of surface characterization and hydrogen plasma diagnosis using the vacuum ultraviolet (VUV) line absorption technique. The reduction model was derived by assuming that the diffusion of atomic hydrogen in the reduced layer is the rate-determining step, This reduction model provides a good approximation of the Cu2O reduction process. The surface hydrogen concentration estimated from this model is higher by an order of 10(5)-10(6) than the hydrogen atom concentration in the plasma phase measured by means of the plasma diagnosis. It is verified that the number of hydrogen atoms transported onto the solid surface satisfactorily agrees with that consumed in the Cu2O layer.