The effect of Fe content in electrodeposited CoFe/Cu multilayers on structural, magnetic and magnetoresistance characterizations.

A series of CoFe/Cu multilayers were electrodeposited on Ti substrates from the electrolytes containing their metal ion under potentiostatic control, but the Fe concentration in the electrolytes was changed from 0.0125 M to 0.2 M. The deposition was carried out in a three-electrode cell at room temperature. The deposition of Cu layers was made at a cathode potential of -0.3 V with respect to saturated calomel electrode (SCE), while the ferromagnetic CoFe layers were deposited at -1.5 V versus SCE. The structural studies by X-ray diffraction revealed that the multilayers have face-centered-cubic structure. The magnetic characteristics of the films were investigated using a vibrating sample magnetometer and their easy-axis was found to be in film plane. Magnetoresistance measurements were carried out using the Van der Pauw method at room temperature with magnetic fields up to +/- 12 kOe. All multilayers exhibited giant magnetoresistance (GMR) and the GMR values up to 8% were obtained.