Analysis on structure, magnetic and magneto-optical properties of vacuum annealed Co/Pt multilayer films

Co/Pt multilayer films were prepared by DC magnetron sputtering. Detailed vacuum annealiug was carried out on them. The results show that moderate annealing at lower temperature canimcrease the coercivity in Co/Pt multilayer films while not affect the shape of Kerr hysterisis loops.Annealing at or above 300℃ will cause the drastic decrease in coercivity, perpendiculax magneticanisotropy ajnd Kerr rotation in Co/Pt multilayer films. The improvement of crystal structure andthe release of stresses in films, the growth of grains, the reduction of effective Co layer thicknesscaused by atom diffusion between layers and further the decrease in Curie temperature are considered to be responsible for the changes in magnetic and magneto-optical properties for Co/Ptmultilayer films during lower, middle and higher temperature annealing, respectively.