Copper films alloyed with 1 wt.% of Ti are metallized on polyimide (PI) films. The surface of the PI is treated with an O-2-containing plasma prior to Cu(Ti) deposition in order to modify the Cu(Ti)/PI interface. The stacked films are characterized, in view of the Ti incorporation and of the PI surface treatment, with scratch tests, Rutherford backscattering spectroscopy, X-ray diffraction, and X-ray photoelectron spectroscopy.