| 摘要 |
IN A MAGNETIC RECORDING MEDIUM, SURFACE ROUGHNESS OF A GLASS SUBSTRATE (1) AND THE VARIATION OF THE SURFACE ROUGHNESS ARE SUPPRESSED TO THE PREDETERMINED RANGE. NAMELY, THE SURFACE ROUGHNESS (Rmax, Ra, Rq) AND THE RELATION (Rmax/Ra) BETWEEN Rmax AND Ra ARE RESTRICTED TO THE PREDETERMINED RANGE. IN THIS EVENT, Ra IS REPRESENTATIVE OF A CENTER-LINE MEAN ROUGHNESS, Rmax IS DEFINED AS A MAXIMUM HEIGHT REPRESENTATIVE OF A DIFFERENCE BETWEEN A HIGHEST POINT AND A LOWEST POINT AND Rq IS REPRESENTATIVE OF A ROOT MEAN SQUARE ROUGHNESS. THEREBY, CRYSTAL GRAINS OF AN UNDERLYING LAYER (2, 3, 5) AND A MAGNETIC LAYER (6) FORMED THEREON ARE EQUALIZED. SPECIFICALLY, THE SURFACE ROUGHNESS IS SPECIFIED BY Rmax < 15 nm, Ra < 1 nm AND Rq < 1.5 nm. FURTHER, THE RATIO BETWEEN THE SURFACE ROUGHNESS Rmax AND THE SURFACE ROUGHNESS Ra IS SPECIFIED BY Rmax/Ra < 30. |
