| 摘要 |
PURPOSE:To obtain the function to accelerate the rapid cooling of a recording film at the time of conversion to an amorphous state and to enable overwriting by using a high thermal conductor having the m. p. higher than the m. p. of the recording film and the thermal conductivity higher than the thermal conductivity of the recording film to form at least one protective film. CONSTITUTION:At least one of the protective film of the protective films 2, 4 provided to sandwich the recording film 3 or adjacently to one surface of the recording film 3 is formed of the material (metallic film or semiconductor film)having the m. p. higher than the m. p. of the recording film 3 and the thermal conductivity higher than the thermal conductivity of the recording film 3. Namely, the deformation or oxidation of the recording film 3 with the heat history at the time of recording is prevented by using the film of a high melting material, for example, a high melting metal film as the protective films 2, 4 and further, the diffusion of the heat generated in the recording film 3 at the time of recording into the protective films 2, 4 without stagnation in the recording film is possible by using the film having the thermal conductivity higher than the thermal conductivity of the recording film 3 is used as the high melting metal film. The rapid cooling of the phase change film at the time of conversion of the film to the amorphous state by heating the recording film 3 to its m. p. or above and rapidly cooling the film is accelerated. Overwriting is thus enabled. |
