Study on the coercivity variation in Pt/Co multilayer films after vacuum annealing

Effects of vacuum annealing on the coercivity in sputtered and evaporated Pt/Co multilayer films were detailedly investigated. Our experimental results showed that the coercivity experienced an initial increase and a subsequent decrease with the process of annealing. The saturation magnetization decreased slowly at initial annealing stage and then dropped drastically when the annealing temperature was further raised. The coercivity variation after vacuum annealing can be explained by the improvement of f.c.c. (111) texture and the reduction of Co layer thickness.