Optical information recording medium and method of manufacturing the same

Abstract

An optical information recording medium includes an oxide/nitride dielectric film that shows a film forming rate higher than that of SiON film and hence is adapted to mass production. The recording medium shows little change in the reflectivity after a long environment test. A first dielectric layer made of ZnS—SiO, an oxide/nitride dielectric layer made of silicon-nickel oxide/nitride, a second dielectric layer made of ZnS—SiO, a first interface layer made of GeN, a recording layer made of GeSbTe, a second interface layer made of GeN, a third dielectric layer made of ZnS—SiOand a reflection layer are laid sequentially on a transparent substrate in the above mentioned order. The oxide/nitride dielectric layer is formed by reactive sputtering in a mixed gas atmosphere containing Ar gas, Ogas and Ngas. The refractive index of the oxide/nitride dielectric layer is made lower than that of the first dielectric layer and that of the second dielectric layer and the light absorption coefficient of the recording layer is made lower in an amorphous state than in a crystalline state.