Abstract: A thin film magnetic media structure with a pre-seed layer of CrTi is disclosed. The CrTi pre-seed layer presents an amorphous or nanocrystalline structure. The preferred seed layer is RuAl for use with the CrTi pre-seed layer. The use of the CrTi/RuAl bilayer structure provides superior adhesion to the substrate and resistance to scratching, as well as, excellent coercivity and signal-to-noise ratio (SNR) and reduced cost over the prior art. One embodiment of the invention sputter-deposits a CrTi pre-seed layer and a RuAl seed layer followed by at least one underlayer and at least one magnetic layer on a circumferentially polished substrate structure to achieve an Mrt orientation ratio greater than one. Two methods according to the invention allow the Mrt orientation ratio of the disk to be adjusted or maximized by varying the thickness of the RuAl seed layer and/or altering the atomic percentage of titanium in the pre-seed layer.

Abstract: A magnetic thin film disk for use in a disk drive with a ruthenium-aluminum (RuAl) seed layer with B2 structure followed by a NiAl layer is described. The disk has reduced noise and increased squareness which results in improved recording performance in a disk drive utilizing the disk. The improved disk is formed by first depositing the RuAl seed layer on the substrate then the NiAl layer is deposited onto the NiAl, followed by the other layers required for a magnetic disk such as an underlayer material with a lattice parameter compatible with RuAl such as Cr-alloy, followed by a standard hcp magnetic material. The RuAl seed layer promotes a [100] preferred orientation in the underlayer which in turn promotes a [11{overscore (2)}0] preferred orientation in the magnetic layer.

Abstract: A magnetic thin film disk for use in a disk drive with a ruthenium-aluminum (RuAl) seed layer with B2 structure followed by a NiAl layer is described. The disk has reduced noise and increased squareness which results in improved recording performance in a disk drive utilizing the disk. The improved disk is formed by first depositing the RuAl seed layer on the substrate then the NiAl layer is deposited onto the NiAl, followed by the other layers required for a magnetic disk such as an underlayer material with a lattice parameter compatible with RuAl such as Cr-alloy, followed by a standard hcp magnetic material. The RuAl seed layer promotes a [100] preferred orientation in the underlayer which in turn promotes a [11{overscore (2)}0] preferred orientation in the magnetic layer.

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 onset layer has an optimal concentration of 28-33 at. % Cr and an optimal thickness of 0.5 to 2.5 nm and it increases coercivity and improves the Signal-to-Noise Ratio (SNR) of the disk. 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.

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.

Abstract: The thin film disk includes a pre-seed layer of amorphous or nanocrystalline structure which may be CrTa or 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 onset layer has an optimal concentration of 28-33 at. % Cr and an optimal thickness of 0.5 to 2.5 nm and it increases coercivity and improves the Signal-to-Noise Ratio (SNR) of the disk.

Abstract: A thin film magnetic media structure comprising a pre-seed layer CrTi is disclosed. The CrTi pre-seed layer presents an amorphous or nanocrystalline structure. The preferred seed layer is RuAl. The use of the CrTi/RuAl bilayer structure provides superior adhesion to the substrate and resistance to scratching, as well as, excellent coercivity and signal-to-noise ratio (SNR) and reduced cost over the prior art.

Abstract: The design of a magnetic thin film disk, for use in a disk drive, with an amorphous or nanocrystalline pre-seed layer preferably followed by a ruthenium-aluminum (RuAl) seed layer is described. The pre-seed layer may be CrTa or AlTi. The pre-seed layer deposited over a glass substrate, for example, allows a more strongly oriented RuAl seed layer to be deposited and, thus, favorably influences the orientation and grain size in the subsequent layers which include preferably at least one Cr alloy underlayer and at least one magnetic layer.

Abstract: In a thin film magnetic disk, a crystalline CrNi pre-seed layer is sputtered onto a substrate such as glass, followed by a RuAl seed layer. The CrNi pre-seed layer reduces grain size and its distribution, and improves in-plane crystallographic orientation, coercivity (Hc) and SNR. In a preferred embodiment the RuAl seed layer is followed by a Cr alloy underlayer. In a preferred embodiment the Cr alloy underlayer is followed by an onset layer and a magnetic layer, or by two or more magnetic layers antiferromagnetically coupled through one or more spacer layers. The crystalline CrNi pre-seed layer allows use of a thinner RuAl seed layer which results in smaller overall grain size, as well as a reduction in manufacturing cost due to relatively high cost of ruthenium. The CrNi pre-seed layer also allows use of a thinner Cr alloy underlayer which also contributes to reduce overall grain size.

Abstract: A thin film magnetic media structure with a pre-seed layer of CrTi is disclosed. The CrTi pre-seed layer presents an amorphous or nanocrystalline structure. The preferred seed layer is RuAl for use with the CrTi pre-seed layer. The use of the CrTi/RuAl bilayer structure provides superior adhesion to the substrate and resistance to scratching, as well as, excellent coercivity and signal-to-noise ratio (SNR) and reduced cost over the prior art. One embodiment of the invention sputter-deposits a CrTi pre-seed layer and a RuAl seed layer followed by at least one underlayer and at least one magnetic layer on a circumferentially polished substrate structure to achieve an Mrt orientation ratio greater than one. Two methods according to the invention allow the Mrt orientation ratio of the disk to be adjusted or maximized by varying the thickness of the RuAl seed layer and/or altering the atomic percentage of titanium in the pre-seed layer.

Abstract: A thin film magnetic media structure comprising a pre-seed layer CrTi is disclosed. The CrTi pre-seed layer presents an amorphous or nanocrystalline structure. The preferred seed layer is RuAl. The use of the CrTi/RuAl bilayer structure provides superior adhesion to the substrate and resistance to scratching, as well as, excellent coercivity and signal-to-noise ratio (SNR) and reduced cost over the prior art.

Abstract: The thin film magnetic disk of the present invention includes a non-metallic substrate having a seed layer deposited on the substrate, an underlayer deposited upon the seed layer composed of a chromium alloy having a relatively high oxygen concentration portion of from 2,000 ppm to 20,000 ppm and preferably approximately 4,000 ppm to 12,000 ppm, followed by a relatively low oxygen concentration portion of from 0-2,000 ppm, and preferably from 500 ppm to 1,500 ppm and a magnetic layer that is deposited upon the underlayer. The underlayer total thickness is in the range of from approximately 250 Å to approximately 700 Å with a preferred thickness of approximately 450 Å, wherein approximately half of the underlayer thickness is the high oxygen concentration portion and half is the low oxygen concentration portion.

Abstract: The thin film disk of the invention includes a thin film pre-seed layer of amorphous or nanocrystalline structure. The pre-seed layer, which may be chromium-tantalum (CrTa) or aluminum-titanium (AlTi) or aluminum-tantalum (AlTa), is deposited prior to a first crystalline layer. Although the pre-seed layer may be amorphous or nanocrystalline, for brevity it will be referred to herein as amorphous which is intended to encompass a nanocrystalline structure. In the preferred embodiment of the present invention, a pre-seed layer is sputtered onto a non-metallic substrate such as glass, followed by a ruthenium-aluminum (RuAl) layer with B2 structure. The use of the pre-seed layer improves grain size and its distribution, in-plane crystallographic orientation, coercivity (Hc) and SNR. In a preferred embodiment of the present invention, the pre-seed layer is followed by the RuAl seed layer, a Cr alloy underlayer, an onset layer and a magnetic layer.

Abstract: The thin film disk of the invention includes a thin film pre-seed layer of amorphous or nanocrystalline structure. The pre-seed layer, which may be CrTa or AlTi or AlTa, is deposited prior to a first crystalline layer. Although the pre-seed layer may be amorphous or nanocrystalline, for brevity it will be referred to herein as amorphous which is intended to encompass a nanocrystalline structure. In the preferred embodiment of the present invention, a pre-seed layer is sputtered onto a nonmetallic substrate such as glass, followed by a ruthenium-aluminum (RuAl) layer with B2 structure. The use of the pre-seed layer improves grain size and its distribution, in-plane crystallographic orientation, coercivity (Hc) and SNR. In a preferred embodiment of the present invention, the pre-seed layer is followed by the RuAl seed layer, a Cr alloy underlayer, an onset layer and a magnetic layer.

Abstract: The thin film disk of the invention includes a thin film pre-seed layer of amorphous or nanocrystalline structure. The pre-seed layer, which may be chromium-tantalum (CrTa) or aluminum-titanium (AlTi) or aluminum-tantalum (AlTa), is deposited prior to a first crystalline layer. Although the pre-seed layer may be amorphous or nanocrystalline, for brevity it will be referred to herein as amorphous which is intended to encompass a nanocrystalline structure. In the preferred embodiment of the present invention, pre-seed layer is sputtered onto a nonmetallic substrate such as glass, followed by a ruthenium-aluminum (RuAl) layer with B2 structure. The use of the pre-seed layer improves grain size and its distribution, in-plane crystallographic orientation and coercivity (Hc) and SNR. In a preferred embodiment of the present invention, the pre-seed layer is followed by the RuAl seed layer, a Cr alloy underlayer, an onset layer and a magnetic layer.

Abstract: A thin film magnetic disk (and a disk drive using the magnetic disk) with improved recording performance having a thin seed layer consisting of tantalum (Ta), a suitable underlayer and a CoPtCrB magnetic layer is described. The underlayer is preferably a Cr alloy with a grain size which is smaller than that of pure Cr. CrTi is suitable as an underlayer. An appropriate overcoat such as hydrogenated carbon can be applied.

Abstract: A thin film disk and a disk drive using the thin film disk are described. The disk has an onset layer between the underlayer and the boron containing magnetic layer, for example. The onset layer of the invention is useful because the boron containing magnetic layer material resists being deposited with the C-axis in plane. The onset layer material is selected to promote an in-plane C-axis orientation. When a boron containing magnetic layer is deposited on the onset layer the resulting in-plane PO is improved. The preferred onset layer is of hexagonal closed pack structured material which may be magnetic or nonmagnetic. Materials which are usable for the onset layer include a wide range of pure elements and cobalt alloys such as CoCr, CoPtCr, CoPtCrTa and CoCrB.

Abstract: A thin film disk with laminated magnetic layers, for use in a disk drive, is described which exhibits a single switching behavior resulting in a smooth hysteresis loop. This is achieved by depositing a seed layer prior to depositing the Cr or Cr alloy underlayer. The seed layer material is selected to promote a [112] PO in the underlayer and subsequently a [1010] PO in the two or more laminated magnetic layers. The [1010] PO aids in maintaining minimal Hc variations between the magnetic layers. The seed layer can be a B2 type structure material such as NiAl or FeAl or any other material which results in the [112] PO in the underlayer. The underlayer is preferably Cr or a Cr alloy; the magnetic layers are preferably CoPtCr, CoPtCrTa or CoPtCrB. The spacer layer between the magnetic layers may be made from the same material as the underlayer, but may also be different, e.g. an hexagonal crystalline material such as Ru.

Abstract: The present invention describes a disk drive and a thin film magnetic disk with improved recording performance of a magnetic medium having a thin seed layer material consisting of a CrTi alloy between the underlayer and the substrate. The seed layer thickness should be between 5-150.ANG. with 5-30.ANG. being preferable. The percentage of Ti should be greater than 5 at % with recording performance of the magnetic medium improving with increased percentage of Ti. The addition of Ti to Cr, increases the operable thickness range for the seed layer and, thereby, improves the manufacturability.

Abstract: A thin film cobalt alloy magnetic recording disk has a metal nitride layer located between the disk substrate and the top surface of the disk to provide texturing of the disk at the head-disk interface. The texturing layer is made up of generally contiguous clusters of aluminum nitride (AlN) with rounded upper surfaces that are formed on top of the substrate and under the conventional Cr underlayer. The AlN texturing layer is formed by sputtering an Al target in the presence of N.sub.2 gas. The subsequently sputter-deposited Cr underlayer, cobalt alloy magnetic layer and protective amorphous carbon overcoat replicate the upper surface of the contiguous AlN clusters, resulting in a textured surface at the head-disk interface. The AlN texturing layer may also be sputter deposited above the magnetic layer in the middle of the protective carbon overcoat.