| 摘要 |
PURPOSE:To make possible an increase in recording capacity by providing one or plural layers of recording layers whose heat conductivity is smaller in the intra-plane direction than in the thickness direction on a substrate. CONSTITUTION:The recording layer consisting of one or plural layers is provided on the substrate. The recording layer of which the heat conductivity in the depth direction is larger than in the intra-plane direction is used. Holes of different depths can be formed by changing the recording layers to be formed with holes in the case of laminating the four different recording layers 3-6 on the substrate 2. The heat conductivity in the intra-plane direction is suppressed and the holes having the uniform diameter in the depth direction are formed unless the heat conductivity in the depth direction is larger than the intra-plane direction. Thin films formed by subjecting a material such as BeO or ZnS to C-axis orientation in the thickness direction or the thin films laminated alternately with many layer of said films and the thin films of vanadyl phthalcyanine, Te, etc. are also usable as the medium having the heat conductive anisotropy. |
