Abstract
Rare earth-transition metal amorphous alloy films are promising for use as a magnetooptical memory material. Corrosion resistance as well as magneto-optical properties is very important to obtain highly reliable memory media. Therefore, a study was made on improving both corrosion resistance and magneto-optical properties for TbFe alloy films by adding Ni and/or Co. Corrosion resistance was estimated quantitatively by measuring optical transmittance changes of films immersed in a 1N NaCl solution. Tc increased when Ni was added in TM rich region, and this increase in Tc decreased with increasing Tb concentration. But in Tb rich region Tc was decreased by the addition of Ni, and Tc increased steeply when Co was added. θk increased when Co was added and decreased gradually when Ni was added. The additions of these materials caused remarkable increase in corrosion resistance. From the results, it is concluded that memory media having both high corrosion resistance and good magneto-optical properties can be obtained by using TbNiCoFe amorphous films.
