Thermal Stability and Reliability of Magneto-Optical Media with Periodic Structures

Using a constant power source and both binary and single target magnetron sputtering, samples with periodic structures were produced while varying the substrate rotation speed. Characteristics reached a maximum at 5 rpm and in-plane magnetization films resulted at 1 rpm. Annealing samples with a protective layer causes all characteristics except the Kerr rotation angle (θ_K) to vary. These variations were peculiar to periodic structures. The change in the coercive force (H_c) indicated a structural transition. The large H_c and saturation magnetization (M_s) values promise superior recording resolution. The carrier-to-noise ratio was improved by one to two dB and showed no changes after 1000 h in the open air at 55°C.