| 摘要 |
AN OBJECT OF THE PRESENT INVENTION IS TO PROVIDE A MAGNETIC RECORDING MEDIUM EXHIBITING LOW NOISE AND HAVING SUFFICIENTLY HIGH COERCIVE FORCE. THE MAGNETIC LAYER (4) HAS A GRANULAR STRUCTURE CONSISTING OF FERROMAGNETIC CRYSTAL GRAINS WITH HEXAGONAL CLOSEST PACKED STRUCTURE AND NONMAGNETIC GRAIN BOUNDARY REGION OF MAINLY OXIDE INTERVENING BETWEEN THE CRYSTAL GRAINS. THE UNDERLAYER (2) HAS BODY-CENTERED CUBIC LATTICE STRUCTURE. A NONMAGNETIC INTERMEDIATE LAYER (3) WITH HEXAGONAL CLOSEST PACKED STRUCTURE MAINLY COMPOSED OF ONE OR MORE ELEMENT SELECTED FROM A GROUP CONSISTING OF RU, OS, AND RE IS PROVIDED BETWEEN THE MAGNETIC LAYER (4) AND THE UNDERLAYER (2). A DEGREE OF MISMATCHING ∆=⁄D1-D2/D1 IS AT MOST 10%, PREFERABLY IN THE RANGE FROM 2.5% TO 7.0%,WHERE D1 IS A SPACING OF LATTICE PLANES OF CRYSTAL GRAINS AND D2 IS A SPACING OF THE LATTICE PLANES OF THE CRYSTAL GRAINS IN THE INTERMEDIATE LAYER (3). A PROPORTION OF CRYSTAL GRAINS WITH GRAIN SIZE OF NOT SMALLER THAN 8NM IS AT MOST 10% OF CRYSTAL GRAINS INCLUDED IN THE INTERMEDIATE LAYER (3) AND A STANDARD DEVIATION OF THE GRAIN SIZE IS AT MOST 1.4NM. THE LAYERS ARE DEPOSITED WITHOUT PREHEATING THE SUBSTRATE (1).
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