| 摘要 |
PURPOSE:To prevent spread of pits, enable crosstalk to be small, and achieve high density by forming a part with a low thermal conductivity in concentric or spiral shape on a recording layer by oxidation, etc. CONSTITUTION:A substrate is rotated within an oxygen atmosphere or a pressure-reduced oxygen atmosphere and at the same time a laser beam 26 is emitted. A part 28 irradiated with the laser beam 26 is oxidized but a part 30 not irradiated with the laser beam 26 is not oxidized since there is no temperature increase and a recording layer 14 is oxidized in concentric or spiral shape. With recording of information, a laser beam with a certain output is applied to a non-oxidized part 22 and at the same time a magnetic field is applied for aligning magnetization of the non-oxidized part 22 of the recording layer 14 in a certain direction, then a direction of application of magnetic field is inverted, a laser beam which is modulated according to information is applied to the non-oxidized part 22 for inverting magnetization and forming pits. At this time, since thermal conductivity at an oxidized part is low, the temperature increase is small and spread of pits can be restricted. |
