Magnetic recording medium, method of manufacturing the same, and magnetic recording/reproduction apparatus

Abstract

According to one embodiment, a magnetic recording medium includes a substrate, an auxiliary layer formed on the substrate, and at least one perpendicular magnetic recording layer formed on the auxiliary layer. The perpendicular magnetic recording layer includes a magnetic dot pattern. The perpendicular magnetic recording layer is made of an alloy material containing one element selected from iron and cobalt, and one element selected from platinum and palladium. This alloy material has the L1 0 structure, and is (001)-oriented. The auxiliary layer includes a dot-like first region covered with the magnetic dot pattern, and a second region not covered with the magnetic dot pattern. The first region is made of a (100)-oriented nickel oxide. The second region contains nickel used in the first region as a main component.

1 . A magnetic recording medium comprising:
 a substrate;   an auxiliary layer on the substrate; and   a perpendicular magnetic recording layer on the auxiliary layer, the perpendicular magnetic recording layer having a magnetic dot pattern comprising a (001)-oriented alloy material, the alloy material having an L1 0  structure and comprising an element selected from the group consisting of iron and cobalt and an element selected from the group consisting of platinum and palladium, and,   wherein the auxiliary layer includes a dot-like first region covered with the magnetic dot pattern and comprising a (100)-oriented nickel oxide, and a second region not covered with the magnetic dot pattern and comprising nickel as a main component.   
     
     
         2 . The medium of  claim 1 , wherein nickel in the second region is formed by reducing a layer made of a (100)-oriented nickel oxide in a reducing ambient by using the magnetic dot pattern as a mask. 
     
     
         3 . The medium of  claim 1 , further comprising a non-magnetic underlayer between the substrate and the auxiliary layer. 
     
     
         4 . The medium of  claim 3 , wherein the non-magnetic underlayer comprises at least one material selected from the group consisting of a (100)-oriented nickel oxide, a (100)-oriented magnesium oxide, a (100)-oriented titanium nitride, and (100)-oriented chromium. 
     
     
         5 . The medium of  claim 3 , further comprising, between the non-magnetic underlayer and the substrate, an amorphous seed layer comprising at least one alloy selected from the group consisting of an Ni—Nb alloy, an Ni—Ta alloy, an Ni—Zr alloy, an Ni—Mo alloy, and an Ni—V alloy. 
     
     
         6 . The medium of  claim 3 , further comprising a soft magnetic underlayer between the substrate and the non-magnetic underlayer. 
     
     
         7 . A method of manufacturing a magnetic recording medium, the method comprising:
 forming, on a substrate, an auxiliary layer by depositing a (100)-oriented nickel oxide;   forming, on the auxiliary layer, a perpendicular magnetic recording layer comprising a (001)-oriented alloy comprising an element selected from the group consisting of iron and cobalt and an element selected from the group consisting of platinum and palladium, and having an L1 0  structure;   partially exposing the auxiliary layer by processing the perpendicular magnetic recording layer into a magnetic dot pattern; and   depositing a protective layer on the perpendicular magnetic recording layer,   wherein before the protective layer is formed, the magnetic dot pattern and the auxiliary layer are exposed to a reducing ambient, and the partially exposed auxiliary layer is reduced by using the magnetic dot pattern as a mask, thereby forming, in the auxiliary layer, a dot-like first region covered with the magnetic dot pattern and comprising the nickel oxide, and a second region not covered with the magnetic dot pattern and comprising nickel as a main component.   
     
     
         8 . The method of  claim 7 , wherein forming the perpendicular magnetic recording layer material comprises heating the substrate to 250° C. to 700° C. 
     
     
         9 . The method of  claim 7 , wherein depositing the perpendicular magnetic recording layer comprises sputtering at a pressure of 3 to 12 Pa. 
     
     
         10 . A magnetic recording/reproduction apparatus comprising:
 a magnetic recording medium comprising:
 a substrate, 
 an auxiliary layer on the substrate, and 
 a perpendicular magnetic recording layer on the auxiliary layer, the perpendicular magnetic recording layer having a magnetic dot pattern comprising a (001)-oriented alloy material, the alloy material having an L1 0  structure and comprising an element selected from the group consisting of iron and cobalt and an element selected from the group consisting of platinum and palladium, 
   auxiliary layer comprising a dot-like first region covered with the magnetic dot pattern and comprising a (100)-oriented nickel oxide, and a second region not covered with the magnetic dot pattern and comprising nickel as a main component; and   a recording/reproduction head.   
     
     
         11 . The apparatus of  claim 10 , wherein nickel in the second region is formed by reducing a layer made of a (100)-oriented nickel oxide in a reducing ambient by using the magnetic dot pattern as a mask. 
     
     
         12 . The apparatus of  claim 10 , further comprising a non-magnetic underlayer between the substrate and the auxiliary layer. 
     
     
         13 . The apparatus of  claim 12 , wherein the non-magnetic underlayer comprises at least one material selected from the group consisting of a (100)-oriented nickel oxide, a (100)-oriented magnesium oxide, a (100)-oriented titanium nitride, and (100)-oriented chromium. 
     
     
         14 . The apparatus of  claim 12 , further comprising, between the non-magnetic underlayer and the substrate, an amorphous seed layer comprising at least one alloy selected from the group consisting of an Ni—Nb alloy, an Ni—Ta alloy, an Ni—Zr alloy, an Ni—Mo alloy, and an Ni—V alloy. 
     
     
         15 . The apparatus of  claim 12 , further comprising a soft magnetic underlayer between the substrate and the non-magnetic underlayer.