PREPARATION OF CU-O FILMS BY SPUTTERING USING HE GAS

Cu-O films have been deposited by rf sputtering using a mixture of Ar, He and O-2 as a sputtering gas. When He was mixed with the sputtering gas, highly oxidized Cu-O films mere obtained with low O-2 content of the sputtering gas, compared with those deposited without He. Activat ed particles in the plasma were investigated by optical emission spect roscopy analysis. This enhancement of oxidation of Cu-O films is relat ed to an increase in O-2(+) and O generated through the Penning ioniz ation process by He-m in neutral excited metastable states.