Studies on microstructure, residual stress, electrical and magnetic properties of nano-crystalline Ni–Cu alloy films deposited by DC magnetron co-sputtering

Nanocrystalline Ni–Cu alloy films with varying Cu concentration from 11% to 43% have been deposited on p-type silicon (100) substrate by DC magnetron co-sputtering. X-ray diffraction technique (XRD) has been used for phase identification, grain size determination and residual stress measurement. Compressive nature of residual stress has been observed in NiCu alloy films. A field emission scanning electron microscopy (FESEM) and a transmission electron microscope (TEM) have been used for the both microstructural and compositional analyses. The electrical resistivity measured by Vander Pauw four probe method increases with increase in alloying element (Cu) concentration in the Ni–Cu alloy films. The magnetic properties analyzed by superconducting quantum interference device (SQUID) shows decrease in both coercivity and saturation magnetization with increase in Cu concentration. (paper)