Patent ID: 7169533

Claim:
A phase-change optical information recording medium comprising, on a transparent substrate, a recording layer in which an optically detectable reversible change between an amorphous phase and a crystalline phase can be caused by irradiation with an energy beam, a reflective layer, a dielectric layer arranged between the recording layer and the reflective layer, a first interface layer arranged between the recording layer and the dielectric layer, and a second interface layer arranged between the dielectric layer and the reflective layer and in contact with the reflective layer; wherein the recording layer, the dielectric layer, and the reflective layer are formed in this order on the substrate, a main component of the reflective layer is Ag; a main component of the dielectric layer is at least one selected from the group consisting of an oxide of Ta, nitride of Ta and a nitrooxide of Ta; the recording layer includes Sb and Te; a thickness of the first interface layer is at least 1 nm and at most 10 nm; the second interface lager includes at least one selected from the group consisting of carbon (C), a nitride of an element α (wherein α is at least one element selected from Sn, In, Zr, Si, Cr, Al, V, Nb, Mo, W, Ti, Mg and Ge), an oxide of element α, a carbide of element α, and a nitrooxide of element α, and the recording medium being able to record and reproduce information with a laser light beam of 300 to 500 nm wavelength.