A magneto-optical recording medium having at least two kinds of films consisting of a rare earth metal-transition metal alloy thin film and a dielectric film formed on a substrate. The dielectric film is formed by sputtering a target in an atmosphere containing at least an oxygen gas or a compound gas...http://www.google.de/patents/US5476713?utm_source=gb-gplus-sharePatent US5476713 - Magneto-optical recording medium
