MAGNETIC DISK AND ITS MANUFACTURE, AND MAGNETIC RECORDING APPARATUS

• Main Authors: KOZU JUNICHI, SASAOKA YASUSHI
• Format: Patent
• Language: English
• Published: 29.09.2000
• Edition: 7
• Subjects: CHEMICAL SURFACE TREATMENT; CHEMISTRY; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATIONOR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY IONIMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; COATING MATERIAL WITH METALLIC MATERIAL; COATING METALLIC MATERIAL; DIFFUSION TREATMENT OF METALLIC MATERIAL; INFORMATION STORAGE; INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORDCARRIER AND TRANSDUCER; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION INGENERAL; METALLURGY; PHYSICS; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THESURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION

PROBLEM TO BE SOLVED: To make a magnetic disk appropriate for use in a recording apparatus of a lamp loading system by forming a non-data area to an outer circumferential part, and making a protecting layer of the non-data area thicker than a protecting layer formed in a uniform thickness to the data area of an inner circumferential part. SOLUTION: A protecting layer is normally set to a front face of a magnetic layer and formed of carbon, carbon hydride, carbon nitride, amorphous carbon, SiC or the like carbonaceous substance, an oxide film of SiO2, Zr2O3 or the like, a silicon film, a nitride film of TiN or the like, etc. A thickness of the protecting film formed to a data area is made uniform and as small as possible, i.e., 1-50 nm. A protecting film thicker than this is formed to an outer circumferential part of a disc-shaped non-magnetic substrate. The outer circumferential part of the non-magnetic substrate with the protecting layer is made a non-data area. The non-data area functions as a durability improvement part to a collision to a head arm encountered in the case of a lamp loading system.