MAGNETIC RECORDING MEDIUM AND ITS PRODUCTION

摘要

PROBLEM TO BE SOLVED: To reduce medium noise, to increase coercive force and to improve overwriting characteristics by specifying value given by subtracting the interplanar spacing of a prescribed face of a nonmagnetic middle layer from that of a prescribed face of a magnetic film. SOLUTION: An underlayer 2 on a glass substrate 1 consists of a thin Al film 2a, a thin Cr film 2b and a thin CrV film 2c from the substrate 1 side. A nonmagnetic middle layer 4 between magnetic layers 3, 5 of a CoPtCr alloy is made of a CrV alloy. Value [d(002) -d(110) ] given by subtracting the interplanar spacing of the bcc (110) face of the middle layer 4 from that of the hcp (002) face of the magnetic layer 5 is 0.002-0.032Å.