| 摘要 |
PURPOSE:To obtain the titled optical disk capable of being recorded with low output by using a metal or an alloy forming a crystal structure different from an equilibrium phase at room temp. by quenching the metal from a solid state at high temps. for the optical recording medium thin film. CONSTITUTION:The thin film of a Zn alloy contg. 40wt% Ag is vapor-deposited on a glass substrate 1 as a recording film 2 by sputtering, then a Ta2O5 film is vapor-deposited thereon by sputtering, and further a protective layer 4 is vapor-deposited thereon by sputtering. The crystal structure of the recording film 2 different from the equilibrium phase at room temp. is shown as the difference in the reflectance of a laser beam. For example, the reflectance of the part irradiated with a laser beam is locally increased, and the reflectance of the unrecorded part is lower than the foregoing reflectance. The optical properties are applied to information recording by transducing the properties into an electric signal. In this case, the reflectance of the recording film 2 which is a metallic film is high, and a laser beam is not sufficiently absorbed. Accordingly, the Ta2O5 thin film having a high refractive index is provided to improve the absorptance. By such a constitution, recording can be carried out with low output, and reproduction and erasing can be performed efficiently. |
