| 摘要 |
PURPOSE:To reduce medium noise by interposing a sputtered Cr-contg. underlayer having prescribed characteristics between a nonmetallic substrate and an underlayer. CONSTITUTION:An amorphous Cr-contg. underlayer 14, a crystalline underlayer 16, a magnetic thin film 18 and a protective carbon overcoat 20 are formed on a hard nonmetallic substrate 12 to produce a disk 10. The crystalline underlayer 14 has about 200-3,000Angstrom thickness and is made of sputtered Cr having (200)-based crystal orientation. The magnetic thin film 18 is formed by sputtering in about 100-800Angstrom thickness. The amorphous Cr-contg. sputtered Cr underlayer 14 has 5-80Angstrom thickness and (110)-based crystal orientation of Cr. Medium noise is reduced by at least about 25%, superior levitation characteristics are ensured and high density recording is carried out. |
