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OwnerYuzuru Hosoe, Yoshibumi Matsuda +5inventors
InventorsYuzuru Hosoe, Yoshibumi Matsuda, Totsuo Yahisa, Kiwamu Tanahashi, Hiroyuki Suzuki, Koji Sakamoto, Akira Kato
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In a magnetic recording medium having Co-based alloy magnetic layer containing Pt formed on a substrate through an underlayer, by forming said underlayer with plural underlayers including double layer structure which is formed by piling up 1st underlayer of Cr-based alloy containing Ti and 2nd underlayer of Cr-based alloy containing at least one element selected from a group comprising Mo and W in this sequence, crystal grain diameter is decreased and then medium noise can be decreased, and c axis is oriented to in-plane direction and then high coercivity can be obtained, consequently the magnetic recording medium having high signal to noise ratio at high recording density region is obtained. Further a small size large capacity magnetic recording system can be provided by combination of said magnetic recording media with a MR (magnetoresistive) head.
A magnetic recording medium having a Co-based alloy magnetic layer containing Pt formed on a substrate through a underlayer, characterized in that said underlayer comprises plural underlayers including double layers structure which is formed by piling up 1st underlayer of Cr-based alloy containing Ti, and 2nd underlayer of Cr-based alloy containing at least one element selected from a group comprising Mo and W, in this sequence.
A producing method of a magnetic recording medium characterized in that the producing process includes a process to heat a substrate previous to forming 1st underlayer on the substrate, and a process to form a 1st underlayer, a 2nd underlayer, and a magnetic layer in this sequence in vacuum chambers by sequential sputtering method after heating the substrate, and that a target which comprises Cr-based alloy containing Ti is used to form said 1st underlayer, and a target which comprises Cr-based alloy containing at least one element selected from a group comprising Mo and W is used to form said 2nd underlayer.
Dependencies are inferred from the claim text.