High anisotropy alloy for thin film disk
AssigneeHitachi Global Storage Technologies Netherlands B.V.
InventorsXiaoping Bian, Mary Frances Doerner, Tim Minvielle, Mohammad Taghi Mirzamaani, Kai Tang
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Abstract
The thin film disk includes a pre-seed layer of amorphous or nanocrystalline structure which may be AlTi or Alta, and that is deposited upon a disk substrate. The pre-seed layer is followed by the RuAl seed layer, a Cr alloy underlayer, an onset layer composed essentially of CoCr and a magnetic layer. The magnetic layer is comprised of CoPtxCrBy, wherein x is the at. % concentration of Pt, y is the at. % concentration of boron, and x>4+y.
Claims44
A thin film magnetic disk comprising:
- a substrate;
- a pre-seed layer with an amorphous or nanocrystalline structure, said pre-seed layer being comprised of AlTa or AlTi;
- a non-magnetic ruthenium-aluminum (RuAl) seed layer deposited over the pre-seed layer;
- at least one non-magnetic underlayer deposited over the RuAl seed layer;
- at least one onset layer deposited over the underlayer;
- and
- at least one magnetic layer deposited over the onset layer, wherein said magnetic layer alloy is comprised of CoPtxCrBy, wherein x is the at. % concentration of Pt, y is the at. % concentration of boron, and x>4+y.
A disk drive comprising:
- a motor for rotating a spindle;
- a thin film magnetic disk mounted on the spindle;
- and
- an actuator assembly including a head for writing magnetic information on the disk as it rotates, wherein said thin film disk includes:
- a substrate;
- a pre-seed layer with an amorphous or nanocrystalline structure, said pre-seed layer being comprised of AlTa or AITi;
- a non-magnetic ruthenium-aluminum (RuAl) seed layer deposited over the pre-seed layer;
- at least one non-magnetic underlayer deposited over the RuAl seed layer;
- at least one onset layer deposited over the underlayer;
- and
- at least one magnetic layer deposited over the onset layer wherein said magnetic layer alloy is comprised of CoPtxCrBy, wherein x is the at. % concentration of Pt, y is the at. % concentration of boron, and x>4+y.
A method of manufacturing a thin film magnetic disk comprising the steps of:
- depositing a pre-seed layer with an amorphous or nanocrystalline structure onto a substrate;
- depositing a crystalline ruthenium-aluminum (RuAl) seed layer over the pre-seed layer, said pre-seed layer being comprised of AlTa or AlTi;
- depositing at least one non-magnetic underlayer over the RuAl seed layer;
- depositing at least one onset layer over the underlayer;
- and
- depositing at least one magnetic layer over the onset layer, wherein said magnetic layer alloy is comprised of CoPtxCrBy, wherein x is the at. % concentration of Pt, y is the at. % concentration of boron, and x>4+y.
Dependencies are inferred from the claim text.