| 摘要 |
PURPOSE: To rewrite while holding excellent recording and reproducing characteristics by specifying the mean composition of an information recording thin film in its thickness direction. CONSTITUTION: An information recording thin film 3 is formed on a board 1 directly or via a protective layer 2, and information is recorded or reproduced by changing the atomic arrangement generated upon irradiating with an energy beam. The mean composition of the film 3 in the thickness direction is represented by a formula (Gea Sbb Tec )1-d Xd , where X is at least one element selected from a group consisting of Cr, Ag, Ba, Co, Ni, Pt, Si, Sr, Au, Cd, Cu, Li, Mo, Mn, Zn, Al, Fe, Pb, Na, Cs, Ga, Pd, Bi, Sn, Ti, V, In, W and lanthanoid element, a, b, c and d satisfy 0.01<=a<=0.67, 0.01<=b<=0.59, 0.25<=c<=0.97, 0.03<=d<=0.3. |
