| 摘要 |
PURPOSE:To provide a phase-change type optical information recording medium which can prevent deterioration of a recording mark by reproducing for a long time without large variation in recording and erasing characteristics and has excellent recording and erasing repeating characteristics. CONSTITUTION:A recording layer is formed of alloy containing antimony(Sb), tellurium(Te), germanium(Ge), and sulfur(S), wherein when presence ratio of atoms in the alloy is set to (Sb-Te-Ge):S=(100-W):W, W is set larger than 0 and 40 or less, and Sb:Te:Ge=(5-60):(35-65):(5-65) is set. Thus, when a sulfur atomic ratio W is No. 1-2-1-4, a decrease in C/N upon increasing of number of reproduction (number of passes) is remarkably improved. |
