SWITCHING CHARACTERISTICS OF CERTAIN SPUTTERED THIN-FILMS

Sputtered thin films with compositions consisting of Co75Ni25, [Co75Ni25]90Mol0and [Co75Ni25]90Ta10 atomic percent were evaluated relative to their magnetic properties as a function of thickness. The maximum coercive force at the optimum thickness (<325 A) was determined to be directly proportional to the saturation magnetization. However, the coercive force was inversely proportional to the saturation magnetization in thicker (> 300 A) films. Magnetization reversal of thick films (1, 000 A) was primarily determined by domain wall displacement which may be followed by coherent rotation. The magnetization reversal in thin films, i.e., at optimum thickness for maximum coercive force, primariy agrees with a chain-of-spheres model or a fanning mechanism. © 1990 IEEE