CO-BASED MULTILAYER FILMS AS NOVEL MAGNETOOPTICAL RECORDING MEDIA

Co/Pd and Co/Pt multilayer films prepared by e-beam evaporation and DC sputtering have been extensively studied for the development of novel megneto-optical recording media. The films deposited on glass substrates hava a [111] fcc texture and a columnar structure has been observed in the samples prepared by e-beam and sputtering at high Ar sputtering pressures. It was found that the magnetic and magneto-optical properties were much dependent on the sublayer and total thicknesses of the films as well as on the preparation method. Perpendicular magnetic anisotropy was observed for samples having a thickness of Co smaller than about 6 angstrom and that of the noble metal larger than about 5 angstrom. The multilayer films turned out to be extremely stable after thermal cycling and no evidence of interdiffusion between the two constituents was observed after a 100 million writing-erasing cycle at a 9.5 mW laser power and 500 ns pulse duration. Carrier-to-noise ratios (CNR) of 46 and 52 dB at a 780 nm laser wavelength were obtained for Co/Pd and Co/Pt magneto-optical disks, respectively.