ONSET LAYER FOR PERPENDICULAR MAGNETIC RECORDING MEDIA
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.
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 %.