| 摘要 |
PURPOSE:To raise crystallization temp., to increase crystallization speed and to improve recording sensitivity by using a mixed crystal system consisting of three kinds of compds. and AgSbTe2 as an active material whose optical constant varies. CONSTITUTION:A heat resistant protective layer 2, a recording layer 3, a heat resistant protective layer 4, an adhesive layer 5 and a protective substrate 6 are successively formed on a substrate 1 to obtain a medium. Laser light is projected on the medium from the substrate 1 side to carry out recording, reproduction and erasure. In the recording layer 3, a Te-Sb-Ag-Ge alloy is used as an active material whose optical constant varies. The compsn. of the alloy is within a region defined by a point A(Ge7Sb6Te16), B(AgGe7Sb7Te18), C(AgGe3Sb15Te27) and D(Ge3Sb14Te24) in the GeTe-Ag2Te-Sb2Te3 pseudo-ternary constitutional diagram. |
