| 摘要 |
PROBLEM TO BE SOLVED: To obtain high recording density by successively forming at least a reproducing layer, nonmagnetic intermediate layer, auxiliary reproducing layer, cutoff layer and recording layer in this order on a transparent substrate in such a manner that each layer except for the nonmagnetic intermediate layer has a specified Curie temp. SOLUTION: A first dialectic layer 12 of a SiN is formed to 70nm thickness on a polycarbonate substrate 11 having 1.1μm track pitch, and then a reproducing layer 13 of Gd0.26 (Fe0.70 Co0.30 )0.74 having 0eum/cc magnetization at room temp. and >=350 deg.C Curie temp. is formed to 20nm to 26nm thickness thereon. Then a nonmagnetic intermediate layer 14 of 5nm thickness, an auxiliary reproducing layer 15 of 30nm thickness, a cutoff layer 16 of 10nm thickness, a recording layer 17 of 40nm thickness, and a second dielectric layer of 18 to 30nm thickness are formed in this order. A protective coating 19 comprising a UV- curing resin is applied on the second dielectric layer 18. It is especially preferable that the nonmagnetic intermediate layer consists of one or more kinds of nitrides of Si, Al, Ti and Ta considering the stability and tenseness of the thin film.
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