Onset layer for perpendicular magnetic recording media

Abstract

A magnetic storage medium according to one embodiment includes a substrate; an onset layer formed above the substrate, the onset layer comprising ruthenium and titanium oxide; and a magnetic oxide layer formed directly on the onset layer. The onset layer is formed directly on a ruthenium underlayer stack having at least one layer of ruthenium formed under a relatively higher pressure and at least one layer of ruthenium formed under a relatively low pressure. A method according to one embodiment includes sputtering using a target of ruthenium and titanium oxide for forming an onset layer above a substrate, the onset layer comprising ruthenium and titanium oxide; and forming a magnetic oxide layer directly on the onset layer. Additional systems and methods are also presented.

What is claimed is: 
     
         1 . A magnetic storage medium, comprising:
 a substrate;   an onset layer formed above the substrate, the onset layer comprising ruthenium and titanium oxide, wherein a deposition thickness of the onset layer is between about 2 angstroms and about 8 angstroms, wherein a titanium oxide concentration in the onset layer is between about 4.0 molecular % and about 12 molecular %; and   a magnetic oxide layer formed directly on the onset layer,   wherein the onset layer is formed directly on a ruthenium underlayer stack having at least one layer of ruthenium formed under a relatively higher pressure and at least one layer of ruthenium formed under pressure.   
     
     
         2 . The medium as recited in  claim 1 , wherein an oxygen concentration in a sputter chamber during formation of the onset layer is between about 0.01 vol % and about 0.5 vol %. 
     
     
         3 . A method, comprising:
 sputtering using a target of ruthenium and titanium oxide for forming an onset layer above a substrate, the onset layer comprising ruthenium and titanium oxide; and   forming a magnetic oxide layer directly on the onset layer.   
     
     
         4 . The method as recited in  claim 3 , wherein oxygen and an inert gas are flowed into sputtering chamber during the sputtering, wherein a volumetric flow rate of the oxygen is between about 1% and about 4% of a total volumetric flow rate of the oxygen and inert gas. 
     
     
         5 . The method as recited in  claim 3 , wherein oxygen is not flowed into a sputtering chamber during formation of any other layers formed by sputtering. 
     
     
         6 . The method as recited in  claim 3 , wherein the target comprises less than about 8 atomic % ruthenium. 
     
     
         7 . The method as recited in  claim 3 , wherein a deposition thickness of the onset layer is between about 5.0 angstroms and about 10 angstroms. 
     
     
         8 . The method as recited in  claim 3 , wherein a deposition thickness of the onset layer is about 7.0 angstroms. 
     
     
         9 . The method as recited in  claim 3 , wherein a titanium oxide concentration in the onset layer is between about 4.0 molecular % and about 12 molecular %. 
     
     
         10 . The method as recited in  claim 3 , wherein:
 a titanium concentration in the onset layer is between about 1.5 atomic % and about 4.0 atomic %, and   an oxygen concentration in the onset layer is between about 3.0 atomic % and about 8.0 atomic %.