Patents by Inventor Hardayal S. Gill

Hardayal S. Gill 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: 9513349
    Abstract: A scissor type magnetic sensor having a magnetic bias structure extending from the back edge of first and second magnetic free layers. The magnetic bias structure is constructed of a magnetic material having a high magnetic moment, such as NiFe with a high Fe content or CoFe. The high magnetic moment bias structure reduces magnetic signal asymmetry while also maintaining high signal amplitude.
    Type: Grant
    Filed: February 6, 2014
    Date of Patent: December 6, 2016
    Assignee: HGST Netherlands B.V.
    Inventors: Hardayal S. Gill, Kuok S. Ho, Suping Song
  • Patent number: 9047893
    Abstract: A magnetic sensor having a first sensor stack portion that includes a free layer, non-magnetic spacer or barrier layer and a portion of a pinned layer structure. The sensor has second sensor stack portion formed over the first sensor stack portion. The second sensor stack portion include includes a second portion of the pinned layer structure and a layer of antiferromagnetic material formed over the. The first sensor stack portion is configured with a width and stripe height that define the functional width and strip height of the sensor, whereas the upper portion can be made wider and deeper without affecting sensor performance. Because the patterning of the first sensor stack portion is performed on a thinner structure than would be necessary to pattern the entire sensor stack, the patterning can be performed with smaller dimensions and increased resolution.
    Type: Grant
    Filed: January 31, 2014
    Date of Patent: June 2, 2015
    Assignee: HGST Netherlands B.V.
    Inventors: Zheng Gao, Hardayal S. Gill, Ying Hong, Quang Le
  • Patent number: 8988834
    Abstract: A magnetoresistive sensor having employing a Mn containing Huesler alloy for improved magnetoresistive performance in a structure that minimizes corrosion and Mn migration. The sensor can be constructed with a pinned layer structure that includes a lamination of layers of Co2MnX and CoFe, where X is Al, Ge or Si. The Co2MnX can be sandwiched between the layers of CoFe to prevent Mn migration into the spacer/barrier layer. The free layer can also be constructed as a lamination of Co2MnX and CoFe layers, and may also be constructed so that the Co2MnX layer is sandwiched between CoFe layers to prevent Mn migration.
    Type: Grant
    Filed: July 23, 2014
    Date of Patent: March 24, 2015
    Assignee: HGST Netherlands B.V.
    Inventor: Hardayal S. Gill
  • Publication number: 20140335377
    Abstract: A magnetoresistive sensor having employing a Mn containing Huesler alloy for improved magnetoresistive performance in a structure that minimizes corrosion and Mn migration. The sensor can be constructed with a pinned layer structure that includes a lamination of layers of Co2MnX and CoFe, where X is Al, Ge or Si. The Co2MnX can be sandwiched between the layers of CoFe to prevent Mn migration into the spacer/barrier layer. The free layer can also be constructed as a lamination of Co2MnX and CoFe layers, and may also be constructed so that the Co2MnX layer is sandwiched between CoFe layers to prevent Mn migration.
    Type: Application
    Filed: July 23, 2014
    Publication date: November 13, 2014
    Applicant: HGST NETHERLANDS B.V.
    Inventor: Hardayal S. Gill
  • Patent number: 8867177
    Abstract: A magnetic read sensor having improved robustness to withstand thermal variations resulting from thermal fly height heating. Improved thermal robustness comes as a result of improved pinned layer pinning. The read head includes an AFM layer having an increased thickness to provide a higher blocking temperature. The read head further includes a pinned layer structure that includes a first magnetic layer adjacent to and exchange coupled with the AFM layer. The first layer comprises a Co—Fe layer with an increased Fe content of 20-30 atomic percent. The pinned layer structure also includes a second magnetic layer that is antiparallel coupled with the AP1 layer. The AP2 layer can be a multi-layer structure that includes a layer of CoFe, a layer of Co—Fe—Hf formed on the layer of Co—Fe, a layer of Co—Fe—B formed on the layer of Co—Fe—Hf, and a second layer of Co—Fe formed on the layer of Co—Fe—B.
    Type: Grant
    Filed: October 28, 2010
    Date of Patent: October 21, 2014
    Assignee: HGST Netherlands B.V.
    Inventors: Satoru Araki, Hardayal S. Gill, Hiroaki Chihaya, Dustin W. Erickson, Haiwen Xi, Chang Man Park
  • Patent number: 8286334
    Abstract: Various embodiments of the present invention pertain to manufacturing pre-sliders by annealing to saturation. According to one embodiment, pre-sliders are lapped to prepare for air bearing surfaces for the pre-sliders. The pre-sliders are annealed to saturation to level off the amount of overcoat expansion for the pre-sliders.
    Type: Grant
    Filed: July 14, 2006
    Date of Patent: October 16, 2012
    Assignee: Hitachi Global Storage Technologies, Netherlands B.V.
    Inventors: Damaris Davis, Hardayal S. Gill, Kenneth D. MacKay, Xiao Z. Wu
  • Patent number: 8284525
    Abstract: A current to perpendicular to plane (CPP) magnetoresistance (MR) read head using current confinement proximal to an air bearing surface (ABS) is disclosed. A CPP MR read head includes a first shield, an MR sensor formed on the first shield, and a second shield contacting the MR sensor proximal to an ABS. The CPP MR read head further includes insulating material between the MR sensor and the second shield, where the insulating material is distal to the ABS to electrically isolate the MR sensor from the second shield distal to the ABS. Sense current injected from the second shield through the MR sensor and into the first shield is confined proximal to the ABS at a location where the second shield contacts the MR sensor.
    Type: Grant
    Filed: December 8, 2011
    Date of Patent: October 9, 2012
    Assignee: HGST Netherlands, B.V.
    Inventors: Hardayal S. Gill, Werner J. Douglas, Wipul P. Jayasekara, Wen-Chien Hsiao
  • Publication number: 20120106006
    Abstract: A magnetic read sensor having improved robustness to withstand thermal variations resulting from thermal fly height heating. Improved thermal robustness comes as a result of improved pinned layer pinning. The read head includes an AFM layer having an increased thickness to provide a higher blocking temperature. The read head further includes a pinned layer structure that includes a first magnetic layer adjacent to and exchange coupled with the AFM layer. The first layer comprises a Co—Fe layer with an increased Fe content of 20-30 atomic percent. The pinned layer structure also includes a second magnetic layer that is antiparallel coupled with the AP1 layer. The AP2 layer can be a multi-layer structure that includes a layer of CoFe, a layer of Co—Fe—Hf formed on the layer of Co—Fe, a layer of Co—Fe—B formed on the layer of Co—Fe—Hf, and a second layer of Co—Fe formed on the layer of Co—Fe—B.
    Type: Application
    Filed: October 28, 2010
    Publication date: May 3, 2012
    Applicant: Hitachi Global Storage Technologies Netherlands B. V.
    Inventors: Satoru Araki, Hardayal S. Gill, Hiroaki Chihaya, Dustin W. Erickson, Haiwen Xi, Chang Man Park
  • Patent number: 8151442
    Abstract: Magnetoresistive (MR) elements having flux guides defined by the free layer. The MR element includes a free layer, a spacer/barrier layer, a pinned layer, and a pinning layer. A back edge of the free layer (opposite the sensing surface of the MR element) extends past a back edge of the spacer/barrier layer. The portion of the free layer extending past the back edge of the spacer/barrier layer defines a continuous flux guide. The flux guide is processed to reduce the conductive characteristics of the flux guide, thereby reducing current shunt loss in the flux guide.
    Type: Grant
    Filed: March 31, 2010
    Date of Patent: April 10, 2012
    Assignee: Hitachi Global Strorage Technologies Netherlands, B.V.
    Inventor: Hardayal S. Gill
  • Publication number: 20120075751
    Abstract: A current to perpendicular to plane (CPP) magnetoresistance (MR) read head using current confinement proximal to an air bearing surface (ABS) is disclosed. A CPP MR read head includes a first shield, an MR sensor formed on the first shield, and a second shield contacting the MR sensor proximal to an ABS. The CPP MR read head further includes insulating material between the MR sensor and the second shield, where the insulating material is distal to the ABS to electrically isolate the MR sensor from the second shield distal to the ABS. Sense current injected from the second shield through the MR sensor and into the first shield is confined proximal to the ABS at a location where the second shield contacts the MR sensor.
    Type: Application
    Filed: December 8, 2011
    Publication date: March 29, 2012
    Inventors: Hardayal S. Gill, Werner J. Douglas, Wipul P. Jayasekara, Wen-Chien Hsiao
  • Patent number: 8136226
    Abstract: Methods and apparatus provide a refill configuration adjacent a back-edge that defines a height of a magnetoresistive read sensor. Milling through layers of the sensor forms the back-edge and may be initially conducted at a first angle of incidence greater than a second angle of incidence. In combination, an insulating material and a polish resistant material, such as a non-magnetic metal, disposed on the insulating material fills a void created by the milling. The sensor further includes first and second magnetic shields with the layers of the sensor along with the polish resistant material and insulating material disposed between the first and second magnetic shields.
    Type: Grant
    Filed: May 16, 2008
    Date of Patent: March 20, 2012
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Hardayal S. Gill, Wipul P. Jayasekara
  • Patent number: 8098463
    Abstract: A current to perpendicular to plane (CPP) magnetoresistance (MR) read head using current confinement proximal to an air bearing surface (ABS) is disclosed. A CPP MR read head includes a first shield, an MR sensor formed on the first shield, and a second shield contacting the MR sensor proximal to an ABS. The CPP MR read head further includes insulating material between the MR sensor and the second shield, where the insulating material is distal to the ABS to electrically isolate the MR sensor from the second shield distal to the ABS. Sense current injected from the second shield through the MR sensor and into the first shield is confined proximal to the ABS at a location where the second shield contacts the MR sensor.
    Type: Grant
    Filed: July 30, 2008
    Date of Patent: January 17, 2012
    Assignee: Hitachi Global Storage Technologies Netherlands, B.V.
    Inventors: Hardayal S. Gill, Werner J. Douglas, Wipul P. Jayasekara, Wen-Chien Hsiao
  • Patent number: 7974047
    Abstract: A current to perpendicular to plane (CPP) differential magnetoresistance (DMR) read head using current confinement proximal to an air bearing surface (ABS) is disclosed. The CPP DMR read head includes a first electrically conductive lead, a first MR sensor formed on the first lead, and a non-magnetic electrically conductive spacer formed on the first MR sensor proximate to the ABS. The CPP DMR read head further includes insulating material on the first MR sensor distal to the ABS. A second MR sensor is formed in contact with the conductive spacer such that the second MR sensor is in electrical contact with the first MR sensor proximate to the ABS and is electrically isolated from the first MR sensor distal to the ABS. A second electrically conductive lead is in contact with the second MR sensor. Sense current injected into the first and the second MR sensor is confined proximate to the ABS.
    Type: Grant
    Filed: September 2, 2008
    Date of Patent: July 5, 2011
    Assignee: Hitachi Global Storage Technologies Netherlands, B.V.
    Inventors: Hardayal S. Gill, Douglas J. Werner, Wen-Chien Hsiao, Wipul P. Jayasekara
  • Publication number: 20100187198
    Abstract: Magnetoresistive (MR) elements having flux guides defined by the free layer are disclosed. The MR element includes a free layer, a spacer/barrier layer, a pinned layer, and a pinning layer. A back edge of the free layer (opposite the sensing surface of the MR element) extends past a back edge of the spacer/barrier layer. The portion of the free layer extending past the back edge of the spacer/barrier layer defines a continuous flux guide. The flux guide is processed to reduce the conductive characteristics of the flux guide, thereby reducing current shunt loss in the flux guide.
    Type: Application
    Filed: March 31, 2010
    Publication date: July 29, 2010
    Inventor: HARDAYAL S. GILL
  • Patent number: 7746602
    Abstract: A magnetic read head and a method for manufacturing a magnetic read head are provided. In one embodiment, the method includes providing the magnetic read head comprising a pinning layer disposed over a substrate of the magnetic read head, a pinned layer, a reference layer, a tunneling barrier layer, and a free layer, wherein the free layer is in contact with the tunneling barrier layer. The method further includes milling partially through the free layer from a back surface, thereby creating an exposed face of the free layer which is parallel to the substrate and oxidizing a portion of the free layer between the exposed face and the tunneling barrier layer. The method further includes milling through the free layer, tunneling barrier layer, reference layer, pinned layer, and pinning layer along lateral sides of the magnetic read head.
    Type: Grant
    Filed: June 21, 2006
    Date of Patent: June 29, 2010
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventor: Hardayal S. Gill
  • Patent number: 7746603
    Abstract: A magnetoresistive sensor and method for forming the magnetoresistive sensor. The magnetoresistive sensor includes a first layer and an antiparallel free layer disposed on the first layer. The antiparallel free layer includes a first free layer disposed on the first layer and a first ferromagnetic coupling free layer disposed on the first free layer. The first ferromagnetic coupling layer is configured to provide increased coupling between the first free layer and an antiferromagnetic coupling layer. The antiparallel free layer also includes the antiferromagnetic coupling layer disposed on the first ferromagnetic coupling free layer, a second ferromagnetic coupling free layer disposed on the antiferromagnetic coupling layer, and a second free layer disposed on the second ferromagnetic coupling free layer. The second ferromagnetic coupling layer is configured to provide increased coupling between the second free layer and the antiferromagnetic coupling layer.
    Type: Grant
    Filed: December 19, 2006
    Date of Patent: June 29, 2010
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventor: Hardayal S. Gill
  • Patent number: 7719801
    Abstract: Magnetoresistive (MR) elements having flux guides defined by the free layer are disclosed. The MR element includes a free layer, a spacer/barrier layer, a pinned layer, and a pinning layer. A back edge of the free layer (opposite the sensing surface of the MR element) extends past a back edge of the spacer/barrier layer. The portion of the free layer extending past the back edge of the spacer/barrier layer defines a continuous flux guide. The flux guide is processed to reduce the conductive characteristics of the flux guide, thereby reducing current shunt loss in the flux guide.
    Type: Grant
    Filed: April 18, 2006
    Date of Patent: May 18, 2010
    Assignee: Hitachi Global Storage Technologies Netherlands, B.V.
    Inventor: Hardayal S. Gill
  • Publication number: 20100053818
    Abstract: A current to perpendicular to plane (CPP) differential magnetoresistance (DMR) read head using current confinement proximal to an air bearing surface (ABS) is disclosed. The CPP DMR read head includes a first electrically conductive lead, a first MR sensor formed on the first lead, and a non-magnetic electrically conductive spacer formed on the first MR sensor proximate to the ABS. The CPP DMR read head further includes insulating material on the first MR sensor distal to the ABS. A second MR sensor is formed in contact with the conductive spacer such that the second MR sensor is in electrical contact with the first MR sensor proximate to the ABS and is electrically isolated from the first MR sensor distal to the ABS. A second electrically conductive lead is in contact with the second MR sensor. Sense current injected into the first and the second MR sensor is confined proximate to the ABS.
    Type: Application
    Filed: September 2, 2008
    Publication date: March 4, 2010
    Inventors: Hardayal S. Gill, Douglas J. Werner, Wen-Chien Hsiao, Wipul P. Jayasekara
  • Publication number: 20100027167
    Abstract: A current to perpendicular to plane (CPP) magnetoresistance (MR) read head using current confinement proximal to an air bearing surface (ABS) is disclosed. A CPP MR read head includes a first shield, an MR sensor formed on the first shield, and a second shield contacting the MR sensor proximal to an ABS. The CPP MR read head further includes insulating material between the MR sensor and the second shield, where the insulating material is distal to the ABS to electrically isolate the MR sensor from the second shield distal to the ABS. Sense current injected from the second shield through the MR sensor and into the first shield is confined proximal to the ABS at a location where the second shield contacts the MR sensor.
    Type: Application
    Filed: July 30, 2008
    Publication date: February 4, 2010
    Inventors: Hardayal S. Gill, Werner J. Douglas, Wipul P. Jayasekara, Wen-Chien Hsiao
  • Patent number: 7633724
    Abstract: Dual-type tunneling magnetoresistance (TMR) elements and associated methods of fabrication are disclosed that allow for higher bias voltages. In one embodiment, the dual-type TMR element includes a lower pinned layer structure, a lower tunnel barrier layer, a ferromagnetic free layer structure, an upper tunnel barrier layer, and an upper pinned layer structure. The lower pinned layer structure has a first Fermi level, while the upper pinned layer structure has a second Fermi level that is different than the first Fermi level of the lower pinned layer structure. By having different Fermi levels, the bias voltage induced in the TMR element may advantageously be increased without a significant reduction in TMR.
    Type: Grant
    Filed: March 31, 2006
    Date of Patent: December 15, 2009
    Assignee: Hitachi Global Storage Technologies Netherlands, B.V.
    Inventor: Hardayal S. Gill