Patents by Inventor Mary Frances Doerner

Mary Frances Doerner has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 7419730
    Abstract: An antiferromagnetically coupled (AFC) magnetic recording medium with an AFC master layer comprising at least two magnetic layers with the top magnetic layer including copper is described. The slave layer is separated from the master layer structure by a nonmagnetic spacer layer selected to antiferromagnetically couple the layers. The master layer structure according to the invention includes a bottom and top layer of distinct ferromagnetic materials. Preferably, the top layer of the master layer is a cobalt alloy including from 1 to 5 at. % copper with an example being CoPt13Cr20B8Cu2. The AFC magnetic layer structure can be used with a variety of substrates including circumferentially textured glass and NiP/AlMg.
    Type: Grant
    Filed: August 31, 2004
    Date of Patent: September 2, 2008
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Xiaoping Bian, Mary Frances Doerner, Tetsuya Kanbe, Mark Mercado, Mohammad Mirzamaani, Adam Polcyn, Kai Tang
  • Patent number: 7382590
    Abstract: A magnetic head having a free layer and an antiparallel (AP) pinned layer structure spaced apart from the free layer. The AP pinned layer structure includes at least two pinned layers having magnetic moments that are self-pinned antiparallel to each other, the pinned layers being separated by an AP coupling layer constructed of a Ru alloy. The use of a Ru alloy coupling layer significantly increases the pinning field of the AP pinned layer structure over a pure Ru spacer.
    Type: Grant
    Filed: January 31, 2005
    Date of Patent: June 3, 2008
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Mary Frances Doerner, Eric Edward Fullerton, Wen-yaung Lee, Jinshan Li, Brian R. York
  • Patent number: 6872478
    Abstract: The applicants disclose a thin film magnetic media structure with a pre-seed layer of CrTiAl. The CrTiAl pre-seed layer presents an amorphous or nanocrystalline structure. The CrTiAl pre-seed layer improves in-plane c-axis orientation while maintaining a good orientation ratio. The pulse transition width (PW50) is narrowed and the soft error rate is improved. The preferred seed layer is RuAl.
    Type: Grant
    Filed: June 26, 2003
    Date of Patent: March 29, 2005
    Assignee: Hitachi Global Storage Technologies Netherlands, B.V.
    Inventors: Xiaoping Bian, Mary Frances Doerner, Kai Tang, Qi-Fan Xiao
  • Patent number: 6863993
    Abstract: A thin film structure for a magnetic thin film recording medium including a dual seed layer of RuAl/NiAlB is disclosed. The use of the RuAl/NiAlB structure provides reduced grain size, an increased Mrt orientation ratio (OR), increased SNR and lower PW50 at higher amplitude. The RuAl and NiAlB seed layers each have a B2 crystallographic structure. The RuAl/NiAlB dual seed layer can be used to obtain an underlayer with a preferred in-plane orientation of (200) and a cobalt alloy magnetic film with the preferred in-plane orientation of (11{overscore ( )}20).
    Type: Grant
    Filed: September 30, 2003
    Date of Patent: March 8, 2005
    Assignee: Hitachi Global Storage Technologies Netherlands, B.V.
    Inventors: Mary Frances Doerner, Kai Tang, Qi-Fan Xiao
  • Patent number: 6858331
    Abstract: A thin film magnetic media structure with a bi-layer structure of amorphous chromium titanium (CrTi) followed by an amorphous layer of nickel phosphorus (NiP) is disclosed. After the NiP has been deposited it is exposed to oxygen to form an oxidized surface. Preferably the underlayer is deposited directly onto the oxidized NiP surface. The bi-layer structure of CrTi/NiP promotes excellent in-plane crystallographic orientation in the cobalt alloy magnetic layer(s) and allows an ultra-thin chromium underlayer to be used which provides better control over grain size and distribution. When the CrTi/NiP bi-layer structure is combined with a circumferentially textured substrate, preferably glass, a high Mrt orientation ratio (OR) results.
    Type: Grant
    Filed: August 29, 2003
    Date of Patent: February 22, 2005
    Assignee: Hitachi Global Storage Technologies Netherlands, B.V.
    Inventors: Xiaoping Bian, Mary Frances Doerner, Mohammad S. Mirzamaani, Adam Polcyn, Qi-Fan Xiao
  • Patent number: 6852430
    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.
    Type: Grant
    Filed: January 29, 2002
    Date of Patent: February 8, 2005
    Assignee: Hitachi Global Storage Technologies Netherlands, B.V.
    Inventors: Xiaoping Bian, Mary Frances Doerner, James A. Hagan, Tim Minvielle, Mohammad Taghi Mirzamaani, Adam Daniel Polcyn, Kai Tang
  • Patent number: 6846543
    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.
    Type: Grant
    Filed: May 21, 2004
    Date of Patent: January 25, 2005
    Assignee: Hitachi Global Storage Technologies Netherlands, B.V.
    Inventors: Xiaoping Bian, Mary Frances Doerner, Jinshan Li, Mohammad Taghi Mirzamaani, Kai Tang
  • Publication number: 20040265637
    Abstract: The applicants disclose a thin film magnetic media structure with a pre-seed layer of CrTiAl. The CrTiAl pre-seed layer presents an amorphous or nanocrystalline structure. The CrTiAl pre-seed layer improves in-plane c-axis orientation while maintaining a good orientation ratio. The pulse transition width (PW50) is narrowed and the soft error rate is improved. The preferred seed layer is RuAl.
    Type: Application
    Filed: June 26, 2003
    Publication date: December 30, 2004
    Inventors: Xiaoping Bian, Mary Frances Doerner, Kai Tang, Qi-Fan Xiao
  • Publication number: 20040213950
    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.
    Type: Application
    Filed: May 21, 2004
    Publication date: October 28, 2004
    Inventors: Xiaoping Bian, Mary Frances Doerner, Jinshan Li, Mohammad Taghi Mirzamaani, Kai Tang
  • Patent number: 6677052
    Abstract: A magnetic recording disk is provided having an amorphous preseed layer of chromium, titanium, and yttrium. The use of the preseed layer improves the magnetic performance of the disk including signal to noise, inplane orientation, and readback pulsewidth.
    Type: Grant
    Filed: May 29, 2002
    Date of Patent: January 13, 2004
    Assignees: Hitachi Global Storage Technologies, Netherlands B.V.
    Inventors: Xiaoping Bian, Mary Frances Doerner, Kai Tang, Qi-Fan Xiao
  • Publication number: 20030224211
    Abstract: A magnetic recording disk is provided having an amorphous preseed layer of chromium, titanium, and yttrium. The use of the preseed layer improves the magnetic performance of the disk including signal to noise, inplane orientation, and readback pulsewidth.
    Type: Application
    Filed: May 29, 2002
    Publication date: December 4, 2003
    Inventors: Xiaoping Bian, Mary Frances Doerner, Kai Tang, Qi-Fan Xiao
  • Patent number: 6607842
    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.
    Type: Grant
    Filed: January 9, 2001
    Date of Patent: August 19, 2003
    Assignee: Hitachi Globel Storage Technologies Netherlands, B.V.
    Inventors: Xiaoping Bian, Mary Frances Doerner, Tim Minvielle, Mohammad Taghi Mirzamaani, Kai Tang
  • Patent number: 6599642
    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.
    Type: Grant
    Filed: January 9, 2001
    Date of Patent: July 29, 2003
    Assignee: Hitachi Global Storage Technologies Netherlands, B.V.
    Inventors: Xiaoping Bian, Mary Frances Doerner, Tim Minvielle, Mohammad Taghi Mirzamaani, Kai Tang
  • Patent number: 6596409
    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.
    Type: Grant
    Filed: January 9, 2001
    Date of Patent: July 22, 2003
    Assignee: Hitachi Global Storage Technologies Netherlands, B.V.
    Inventors: Xiaoping Bian, Mary Frances Doerner, Tim Minvielle, Mohammad Taghi Mirzamaani, Kai Tang
  • Patent number: 6593009
    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.
    Type: Grant
    Filed: March 2, 2001
    Date of Patent: July 15, 2003
    Assignee: Hitachi Global Storage Technologies Netherlands N.V.
    Inventors: Xiaoping Bian, Mary Frances Doerner, Mohammad Taghi Mirzamaani, Tim Minvielle, Kai Tang
  • Patent number: 6586116
    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.
    Type: Grant
    Filed: February 9, 2000
    Date of Patent: July 1, 2003
    Assignee: Hitachi Global Storage Technologies Netherlands, B.V.
    Inventors: Xiaoping Bian, Mary Frances Doerner, Tim Minvielle, Mohammad Taghi Mirzamaani, Kai Tang, Li Tang
  • Patent number: 6572989
    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.
    Type: Grant
    Filed: June 6, 2001
    Date of Patent: June 3, 2003
    Assignee: International Business Machines Corporation
    Inventors: Xiaoping Bian, Mary Frances Doerner, Tim Minvielle, Mohammad Taghi Mirzamaani, Kai Tang
  • Patent number: 6567236
    Abstract: An antiferromagnetically coupled layer structure for magnetic recording wherein the top ferromagnetic structure is a bilayer structure including a relatively thin first sublayer of ferromagnetic material in contact with the coupling/spacer layer. The first sublayer has a higher magnetic moment than the second sublayer. The layer structure of the invention results improved manufacturability and improved performance. A preferred embodiment of a layer structure according to the invention includes: a bottom ferromagnetic layer preferably of CoCr; an antiferromagnetic coupling/spacer layer preferably of Ru; and a top ferromagnetic structure including a thin first sublayer of material preferably of CoCr, CoCrB or CoPtCrB, and a thicker second sublayer of material preferably of CoPtCrB with a lower moment than the first sublayer.
    Type: Grant
    Filed: November 9, 2001
    Date of Patent: May 20, 2003
    Assignee: International Business Machnes Corporation
    Inventors: Mary Frances Doerner, Eric E. Fullerton, David T. Margulies, Kai Tang
  • Publication number: 20030090831
    Abstract: The applicants disclose an antiferromagnetically coupled layer structure for magnetic recording wherein the top ferromagnetic structure is a bilayer structure including a relatively thin first sublayer of ferromagnetic material in contact with the coupling/spacer layer. The first sublayer has a higher magnetic moment than the second sublayer. The layer structure of the invention results improved manufacturability and improved performance. A preferred embodiment of a layer structure according to the invention includes: a bottom ferromagnetic layer preferably of CoCr; an antiferromagnetic coupling/spacer layer preferably of Ru; and a top ferromagnetic structure including a thin first sublayer of material preferably of CoCr, CoCrB or CoPtCrB, and a thicker second sublayer of material preferably of CoPtCrB with a lower moment than the first sublayer.
    Type: Application
    Filed: November 9, 2001
    Publication date: May 15, 2003
    Inventors: Mary Frances Doerner, Eric E. Fullerton, David Thomas T. Margulies, Kai Tang
  • Patent number: 6537684
    Abstract: A magnetic recording medium for data storage uses a magnetic recording layer having at least two ferromagnetic films exchange coupled together antiferromagnetically across a nonferromagnetic spacer film. In this antiferromagnetically-coupled (AFC) recording layer the magnetic moments of the two ferromagnetic films are oriented antiparallel, and thus the net remanent magnetization-thickness product (Mrt) of the AFC recording layer is the difference in the Mrt values of the two ferromagnetic films. This reduction in Mrt is accomplished without a reduction in thermal stability of the recording medium. The lower ferromagnetic film in the AFC recording layer is a boron-free ferromagnetic CoCr alloy that does not require a nucleation layer between it and the Cr alloy underlayer.
    Type: Grant
    Filed: August 4, 2000
    Date of Patent: March 25, 2003
    Assignee: International Business Machines Corporation
    Inventors: Mary Frances Doerner, Eric Edward Fullerton, David Thomas Margulies