SPUTTERED HEXAGONAL BA-FERRITE FILMS FOR HIGH-DENSITY MAGNETIC RECORDING MEDIA

Ba-ferrite (BaM) thin films were prepared by both a facing targets spu ttering (FTS) system and dc magnetron sputtering (DCMS) at loom temper ature. They were successively annealed to crystallize. The films prepa red by FTS system were crystallized at 650 degrees C, while those prep ared by DCMS system were crystallized at 700 degrees C. Saturation mag netization, coercivity, and squareness ratio of the films prepared by FTS are 210 emu/cc, 3.3 kOe, and 0.7 in perpendicular direction, respe ctively, after the annealing at 650 degrees C. It was found that oxidi zed Fe is partially reduced to metallic Fe by high-temperature anneali ng. (C) 1996 American Institute of Physics.