PROPERTIES AND APPLICATIONS OF VACUUM-DEPOSITED CU-CR FILMS

The application of Cu films is restricted by their low oxidation stabi lity and poor adhesive behaviour. Suggested by the metallurgical and t hin film properties of Cr, one can expect that Cu-Cr composite films a re able to overcome these disadvantages. Films of Cu0.53Cr0.47 prepare d by magnetron sputtering from a mixed target were investigated by ana lytical (transmission electron microscopy, energy-dispersive X-ray spe ctroscopy, Auger electron spectroscopy), electrical (rho(T), temperatu re coefficient of resistivity (TCR)) and mechanical (sigma(T)) measure ments. In combination with the annealing treatment it was found that t he films go through a structural and phase evolution known from co-spu ttering experiments: metastable b.c.c. phase, decomposition into a two -phase region (b.c.c. and f.c.c. phases), further phases by oxidation. The electrical behaviour is characterized by small TCR caused by weak electron localization and by good stability by a self-passivating (Cr 2O3) surface layer. The results of electrical measurements show that t he Cu-Cr films may be used as a metallization system or as a low ohmic resistor at elevated working temperatures.