Patents by Inventor Robert E. Fontana

Robert E. Fontana 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: 7414816
    Abstract: A magnetic head (slider) which requires no lapping is described. The head is fabricated with an air bearing surface that is parallel to the wafer surface. The saw cuts used to separate the individual sliders from the rest of the wafer are perpendicular to the air-bearing surface and do not pass through any critical features. The read and write components are formed from thin films disposed parallel to the air bearing surface and can be side-by-side or tandem in relation to the recording track. The stripe height of the read sensor is controlled by the deposition process rather than by lapping. Various embodiments of the read head include contiguous junction biasing, external hard magnet biasing, and in-stack biasing. In one embodiment a permeable field collector is included below the sensor layer structure. An aperture shield surrounding the sensor at the ABS is included in one embodiment.
    Type: Grant
    Filed: May 28, 2004
    Date of Patent: August 19, 2008
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Robert E. Fontana, Jr., Kuok San Ho, Ching Hwa Tsang
  • Publication number: 20080151596
    Abstract: Magnetic memories and methods are disclosed. A magnetic memory as described herein includes a plurality of stacked data storage layers to form a three-dimensional magnetic memory. Bits may be written to a data storage layer in the form of magnetic domains. The bits can then be transferred between the stacked data storage layers by heating a neighboring data storage layer, which allows the magnetic fields from the magnetic domains to imprint the magnetic domains in the neighboring data storage layer. By imprinting the magnetic domains into the neighboring data storage layer, the bits are copied from one data storage layer to another.
    Type: Application
    Filed: December 22, 2006
    Publication date: June 26, 2008
    Inventors: Robert E. Fontana, Jr., Andreas Moser, Hal J. Rosen, Bruce D. Terris, Ching Hwa Tsang
  • Patent number: 7388776
    Abstract: Magnetic memories and methods are disclosed. A magnetic memory as described herein includes a plurality of stacked data storage layers to form a three-dimensional magnetic memory. Bits may be written to a data storage layer in the form of magnetic domains. The bits can then be transferred between the stacked data storage layers by heating a neighboring data storage layer, which allows the magnetic fields from the magnetic domains to imprint the magnetic domains in the neighboring data storage layer. By imprinting the magnetic domains into the neighboring data storage layer, the bits are copied from one data storage layer to another.
    Type: Grant
    Filed: December 22, 2006
    Date of Patent: June 17, 2008
    Assignee: Hitachi Global Storage Technologies Netherlands, B.V.
    Inventors: Robert E. Fontana, Jr., Andreas Moser, Hal J. Rosen, Bruce D. Terris, Ching Hwa Tsang
  • Publication number: 20080112092
    Abstract: A method and apparatus for oxidizing conductive redeposition in TMR sensors is disclosed. A TMR barrier layer is etched. Redeposition material is oxidized and the barrier is healed using an oxidizing agent selected from the group consisting of ozone and water vapor.
    Type: Application
    Filed: November 10, 2006
    Publication date: May 15, 2008
    Inventors: Robert E. Fontana, Howard G. Zolla
  • Patent number: 7367111
    Abstract: A method and structure for a spin valve transistor (SVT) comprises a magnetic field sensor, an insulating layer adjacent the magnetic field sensor, a bias layer adjacent the insulating layer, a non-magnetic layer adjacent the bias layer, and a ferromagnetic layer over the non-magnetic layer, wherein the insulating layer and the non-magnetic layer comprise antiferromagnetic materials. The magnetic field sensor comprises a base region, a collector region adjacent the base region, an emitter region adjacent the base region, and a barrier region located between the base region and the emitter region. The bias layer is between the insulating layer and the non-magnetic layer. The bias layer is magnetic and is at least three times the thickness of the magnetic materials in the base region.
    Type: Grant
    Filed: January 25, 2006
    Date of Patent: May 6, 2008
    Assignee: Hitachi Global Storage Technologies Netherland BV
    Inventors: Robert E. Fontana, Jr., Jeffrey S. Lille
  • Publication number: 20080088982
    Abstract: Magnetic sensing chips and methods of fabricating the magnetic sensing chips are disclosed. A magnetic sensing chip as described herein includes an EMR sensor formed on a substrate from multiple semiconductor layers. One or more of the semiconductor layers form a quantum well comprising a two-dimensional electron gas (2DEG) or hole gas (2DHG). The magnetic sensing chip also includes one or more transistors formed on the substrate from the multiple semiconductor layers. The transistor(s) likewise include a quantum well comprising a 2DEG or 2DHG. The EMR sensor and the transistor(s) are connected by one or more connections so that the transistor(s) amplifies data signals from the EMR sensor.
    Type: Application
    Filed: October 16, 2006
    Publication date: April 17, 2008
    Inventors: Liesl Folks, Robert E. Fontana, Bruce A. Gurney, Klaas B. Klaassen, Stefan Maat
  • Publication number: 20080037182
    Abstract: A structure for preventing Electrostatic Discharge (ESD) damage to a magnetoresistive sensor during manufacture. The structure includes a switching element that can be switched off during testing of the sensor and then switched back on to provide ESD shunting to the sensor. The switch can be a thermally activated mechanical relay built onto the slider. The switch could also be a programmable resistor that includes a solid electrolyte sandwiched between first and second electrodes. One of the electrodes functions as an anode. When voltage is applied in a first direction an ion bridge forms across through the electrolyte across electrodes making the resistor conductive. When a voltage is applied in a second direction, the ion bridge recedes and the programmable resistor becomes essentially non-conductive.
    Type: Application
    Filed: June 27, 2006
    Publication date: February 14, 2008
    Inventors: Thomas Robert Albrecht, Robert E. Fontana, Bruce Alvin Gurney, Timothy Clark Reiley, Xiao Z. Wu
  • Patent number: 7324313
    Abstract: Current-perpendicular-to-the-plane (CPP), current-in-to-the-plane (CIP), and tunnel valve type sensors are provided having an antiparallel (AP) coupled free layer structure, an in-stack biasing structure which stabilizes the AP coupled free layer structure and a nonmagnetic spacer layer formed between the in-stack biasing layer and the AP coupled free layer structure. The AP coupled free layer structure has a first AP coupled free layer adjacent to the nonmagnetic spacer layer, a second AP coupled free layer, and an antiparallel coupling (APC) layer formed between the first and the second AP coupled free layers. The net moment of the AP coupled free layer structure has an antiparallel edge magnetostatic coupling with the in-stack biasing structure. At the same time, the first AP coupled free layer has an antiparallel exchange coupling with the second AP coupled free layer.
    Type: Grant
    Filed: September 30, 2004
    Date of Patent: January 29, 2008
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Jeffrey Robinson Childress, Robert E. Fontana, Jr., Kuok San Ho, Ching Hwa Tsang
  • Patent number: 7317596
    Abstract: A continuous-media or patterned-media disk drive with a low ratio of linear bit density in bits per inch (BPI) in the along-the-track direction to track density in tracks per inch (TPI) in the cross-track direction has a magnetoresistive read head with high cross-track spatial resolution. The read head is located between two magnetic shields, with the shields and read head formed on a side surface of the head carrier perpendicular to the carrier's disk-facing surface. The carrier is supported by the disk drive actuator with the side surface of the carrier oriented generally parallel to the data tracks. In this arrangement the high-spatial-resolution direction of the read head (the transverse direction perpendicular to the side surface on which the head is formed) is in the radial or cross-track direction.
    Type: Grant
    Filed: June 21, 2005
    Date of Patent: January 8, 2008
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Thomas R. Albrecht, Robert E. Fontana, Jr., Ching Hwa Tsang, Mason L. Williams, Bruce Alexander Wilson
  • Patent number: 7295406
    Abstract: An extraordinary magnetoresistive sensor having optimal magnetic sensitivity capable of reading a very narrow and short magnetic bit. The sensor includes a layer of semiconductor layer and a layer of electrically conductive material. The first and second leads are electrically connected with an edge of the semiconductor material, one of the leads being located a distance inward from an end of the sensor. The sensor also includes first and second voltage leads, located on either side of and close to one of the current leads.
    Type: Grant
    Filed: July 22, 2004
    Date of Patent: November 13, 2007
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Amitava Chattopadhyay, Robert E. Fontana, Jr., Bruce Alvin Gurney, Stefan Maat, Ernesto E. Marinero
  • Patent number: 7290324
    Abstract: A magnetic head including a media heating device. Following the fabrication of the heating device, a sacrificial layer of material is deposited to protect the heating device during subsequent process steps. Thereafter, write head components, such as write head induction coils and/or a P1 pole pedestal are fabricated above the heating device, and the sacrificial layer is substantially consumed in protecting the heating device during the aggressive etching and milling steps used to create those components. Further components, including a second magnetic pole are thereafter fabricated to complete the fabrication of the write head portion of the magnetic head. The sacrificial layer may be comprised of alumina, or a material such as NiFe that can act as a seed layer for a subsequent head components such as the P1 pole pedestal.
    Type: Grant
    Filed: September 19, 2005
    Date of Patent: November 6, 2007
    Assignee: Hitachi Global Storage Technologies Netherlands, B.V.
    Inventors: Robert E. Fontana, Jr., Jeffrey S. Lille
  • Patent number: 7253991
    Abstract: A magnetic head (slider) for perpendicular recording which requires no lapping is described. The head is fabricated with an air bearing surface that is parallel to the wafer surface. The coil and pole pieces are formed from thin films disposed parallel to the air bearing surface. Standard lithographic techniques can be used to define the shapes, gaps and pole piece dimensions. Non-rectilinear shapes can be formed; for example, side shields that conform around the write pole piece region. The thickness of the main and return pole pieces are controlled by the deposition process rather than by lapping. The saw cuts used to separate the individual sliders from the rest of the wafer are perpendicular to the air-bearing surface and do not pass through any critical features.
    Type: Grant
    Filed: April 30, 2004
    Date of Patent: August 7, 2007
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Robert E. Fontana, Jr., Kuok San Ho, Ching Hwa Tsang
  • Patent number: 7203036
    Abstract: An extraordinary magnetoresistance (EMR) sensor has a planar shunt and planar leads formed on top of the sensor and extending downward into the semiconductor active region, resulting. Electrically conductive material, such as Au or AuGe, is first deposited into lithographically defined windows on top of the sensor. After liftoff of the photoresist a rapid thermal annealing process causes the conductive material to diffuse downward into the semiconductor material and make electrical contact with the active region. The outline of the sensor is defined by reactive etching or other suitable etching techniques. Insulating backfilling material such as Al-oxide is deposited to protect the EMR sensor and the edges of the active region. Chemical mechanical polishing of the structure results in a planar sensor that does not have exposed active region edges.
    Type: Grant
    Filed: July 30, 2004
    Date of Patent: April 10, 2007
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Amitava Chattopadhyay, Robert E. Fontana, Jr., Bruce A. Gurney, Stefan Maat, Ernesto E. Marinero
  • Patent number: 7148072
    Abstract: A method and apparatus for oxidizing conductive redeposition in TMR sensors is disclosed. A TMR barrier layer is etched. Redeposition material is oxidized and the barrier is healed using an oxidizing agent selected from the group consisting of ozone and water vapor.
    Type: Grant
    Filed: May 28, 2004
    Date of Patent: December 12, 2006
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Robert E. Fontana, Jr., Howard G. Zolla
  • Patent number: 7079354
    Abstract: A magnetic head including a second magnetic pole (P2 pole) that is fabricated upon a write gap layer that is deposited upon a flat surface. To achieve the flat surface, a P1 pole pedestal is formed upon the P1 pole layer with a sufficient thickness that the induction coil structure can be fabricated beneath the write gap layer. In the preferred embodiment, an etch stop layer is formed upon the P1 pole layer and an ion etching process is utilized to form the induction coil trenches in an etchable material that is deposited upon the etch stop layer. Following the fabrication of the induction coil structure a CMP process is conducted to obtain a polished flat surface upon which to deposit the write gap layer, and the P2 pole is then fabricated upon the flat write gap layer.
    Type: Grant
    Filed: August 14, 2000
    Date of Patent: July 18, 2006
    Assignee: Hitachi Global Storage Technologies Netherlands, B.V.
    Inventors: Robert E. Fontana, Richard Hsiao, Yuexing Zhao
  • Patent number: 7043823
    Abstract: A current-perpendicular-to the-plane (CPP) magnetoresistive device, such as a magnetic tunnel junction (MTJ), is formed by patterning a capping layer (e.g., using resist) in the shape of a central region of an underlying free ferromagnetic layer that in turn resides over additional layers of the MTJ. Side regions of the capping layer are removed by ion milling or etching down into the free ferromagnetic layer. Unmasked side regions of the ferromagnetic layer are then oxidized to render them locally non-ferromagnetic and electrically insulating.
    Type: Grant
    Filed: June 15, 2004
    Date of Patent: May 16, 2006
    Inventors: Jeffrey R. Childress, Elizabeth A. Dobisz, Robert E. Fontana, Jr., Kuok San Ho, Ching Hwa Tsang, Son Van Nguyen
  • Patent number: 7016167
    Abstract: A method and structure for a spin valve transistor (SVT) comprises a magnetic field sensor, an insulating layer adjacent the magnetic field sensor, a bias layer adjacent the insulating layer, a non-magnetic layer adjacent the bias layer, and a ferromagnetic layer over the non-magnetic layer, wherein the insulating layer and the non-magnetic layer comprise antiferromagnetic materials. The magnetic field sensor comprises a base region, a collector region adjacent the base region, an emitter region adjacent the base region, and a barrier region located between the base region and the emitter region. The bias layer is between the insulating layer and the non-magnetic layer. The bias layer is magnetic and is at least three times the thickness of the magnetic materials in the base region.
    Type: Grant
    Filed: April 3, 2003
    Date of Patent: March 21, 2006
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Robert E. Fontana, Jr., Jeffrey S. Lille
  • Patent number: 6999277
    Abstract: A magnetic head including a media heating device. Following the fabrication of the heating device, a sacrificial layer of material is deposited to protect the heating device during subsequent process steps. Thereafter, write head components, such as write head induction coils and/or a P1 pole pedestal are fabricated above the heating device, and the sacrificial layer is substantially consumed in protecting the heating device during the aggressive etching and milling steps used to create those components. Further components, including a second magnetic pole are thereafter fabricated to complete the fabrication of the write head portion of the magnetic head. The sacrificial layer may be comprised of alumina, or a material such as NiFe that can act as a seed layer for a subsequent head components such as the P1 pole pedestal.
    Type: Grant
    Filed: July 30, 2003
    Date of Patent: February 14, 2006
    Assignee: Hitachi Global Storage Technologies Netherlands, B.V.
    Inventors: Robert E. Fontana, Jr., Jeffrey S. Lille
  • Patent number: 6972935
    Abstract: A current-in-the-plane (CIP) giant magnetoresistive (GMR) spin valve sensor has its free layer magnetization stabilized by longitudinal biasing through the use of free layer end-region antiferromagnetic exchange coupling. An antiparallel coupling (APC) layer, such as Ru, is formed on the free layer and a ferromagnetic bias layer is formed on the APC layer. The bias layer is a continuous layer that extends across the entire width of the free layer. The central region of the bias layer is formed of nonmagnetic oxides of one or more of the elements making up the bias layer, with the bias layer end regions remaining ferromagnetic. The oxidized central region of the bias layer defines the central active track-width region of the underlying free layer. The ferromagnetic end regions of the bias layer are antiferromagnetically coupled across the APC layer to the corresponding underlying free layer end regions to provide the longitudinal biasing.
    Type: Grant
    Filed: August 13, 2004
    Date of Patent: December 6, 2005
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Elizabeth A. Dobisz, Robert E. Fontana, Jr., James L. Nix, Neil Smith
  • Patent number: 6949200
    Abstract: The magnetic head of the present invention, includes a second magnetic pole (P2 pole) that is fabricated upon a write gap layer that is deposited upon a flat surface. To achieve the flat surface, a P1 pole pedestal is formed upon the P1 pole layer with a sufficient thickness that the induction coil structure can be fabricated beneath the write gap layer. In the preferred embodiment, an etch stop layer is formed upon the P1 pole layer and an ion etching process is utilized to form the induction coil trenches in an etchable material that is deposited upon the etch stop layer. Following the fabrication of the induction coil structure a CMP process is conducted to obtain a polished flat surface upon which to deposit the write gap layer, and the P2 pole is then fabricated upon the flat write gap layer. The magnetic head of the present invention can be reliably fabricated with a more narrow P2 pole tip base width, such that data tracks written by the magnetic head are likewise narrower.
    Type: Grant
    Filed: June 30, 2003
    Date of Patent: September 27, 2005
    Assignee: Hitachi Global Storage Technologies Netherlands, B.V.
    Inventors: Robert E. Fontana, Richard Hsiao, Yuexing Zhao