A set of [Co(0.2 nm)/Ni(0.4 nm)]10 multilayers (MLs) thin films were fabricated on silicon and glass substrate under various distinct conditions (i) as‐prepared films without an under‐layer, (ii) films with a copper [Cu(2 nm)] underlayer (UL), (iii) films with an in situ annealed Ta/Cu UL during sputtering, and (iv) films with post‐annealing treatment, by using a DC magnetron sputtering machine. The [Co/Ni] MLs thin films prepared under various conditions exhibit in‐plane magnetic anisotropic behavior except as‐prepared films which show isotropic behavior. The maximum saturation magnetization was observed in the as‐prepared films prepared on both silicon and glass substrate. The Ta/Cu UL in situ annealing followed by post‐annealing films exhibit highest coercivity, moderate saturation magnetization but lowest squareness in contrast to the films deposited under other conditions. The I‐V curves of the films show diode like behavior with breakdown voltage of 42, 58, 14, and 21 V for [Co/Ni] MLs under four different conditions.