Patent ID: 7566523

Claim:
An optical information-recording medium, for which recording is performed by irradiating a recording film with a laser beam to change the reflectivity or the optical phase of the recording film, comprising: a first transparent substrate through which the laser beam enters; a first information-recording layer deposited on the first transparent substrate; a first reflection film formed on the first information-recording layer; an intermediate layer deposited on the first reflection film; a second information-recording layer formed on the intermediate layer; a second reflection film deposited on the second information-recording layer; and a second substrate provided on the second reflection film, wherein each of the first and the second information-recording layers is formed such that recording films are sandwiched between first and second dielectric layers, and wherein the recording film of each of the first and second information-recording layers has a main composition represented by (GeTe) x Sb 2−y In y Te 3 , and its composition ratio is within ranges of 0.04≦y≦0.3 and 4≦x≦8, and wherein the thickness of the recording film of each of the first and second information-recording layers is equal to or greater than 6 nm, and equal to or smaller than 13 nm.