Patents by Inventor Calvin S. Lo

Calvin S. Lo 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: 11488629
    Abstract: A method for forming a magnetic recording medium according to one embodiment includes forming a magnetic layer above an underlayer. The magnetic layer includes a first magnetic material and particulates. A protective layer is formed above the magnetic layer, the protective layer including a second material. A method for forming a magnetic recording medium according to another embodiment includes forming a first nonmagnetic layer above a base film. The first nonmagnetic layer has first nonmagnetic particles. A second nonmagnetic layer is formed above the first nonmagnetic layer, the second nonmagnetic layer having second nonmagnetic particles. A magnetic layer is formed above the second nonmagnetic layer, the magnetic layer including a magnetic material.
    Type: Grant
    Filed: June 20, 2019
    Date of Patent: November 1, 2022
    Assignee: International Business Machines Corporation
    Inventors: Robert G. Biskeborn, Calvin S. Lo
  • Patent number: 11393501
    Abstract: A magnetic recording medium according to one embodiment includes a base film and a first nonmagnetic layer above the base film. The first nonmagnetic layer has first nonmagnetic particles. A second nonmagnetic layer is positioned above the first nonmagnetic layer, the second nonmagnetic layer having second nonmagnetic particles. A magnetic layer is positioned above the second nonmagnetic layer, the magnetic layer including a magnetic material.
    Type: Grant
    Filed: June 20, 2019
    Date of Patent: July 19, 2022
    Assignee: International Business Machines Corporation
    Inventors: Robert G. Biskeborn, Calvin S. Lo
  • Patent number: 11322175
    Abstract: A magnetic recording medium according to one embodiment includes an underlayer and a magnetic layer above the underlayer. The magnetic layer includes a first magnetic material and particulates. A solid protective layer is positioned above the magnetic layer, the protective layer including a second material. At least some of the particulates of the magnetic layer protrude completely through the protective layer. A method for forming a magnetic recording medium according to one embodiment includes forming a magnetic layer above a substrate, the magnetic layer including a first magnetic material and particulates, and forming a solid protective layer above the magnetic layer to a thickness whereby some of the particulates protrude through the protective layer and are exposed along an upper surface of the protective layer.
    Type: Grant
    Filed: June 20, 2019
    Date of Patent: May 3, 2022
    Assignee: International Business Machines Corporation
    Inventors: Robert G. Biskeborn, Calvin S. Lo
  • Patent number: 11056132
    Abstract: In one embodiment, an apparatus includes a module having a substrate and a closure, an array of transducers in a thin film structure on the substrate, the array being positioned along a tape bearing surface of the module, and a heating element positioned in the thin film structure and recessed from the tape bearing surface, and a controller electrically coupled to the heating element. The controller is configured to apply a current pulse of size, shape and duration sufficient to induce a permanent expansion of the array of transducers.
    Type: Grant
    Filed: January 8, 2019
    Date of Patent: July 6, 2021
    Assignee: International Business Machines Corporation
    Inventors: Robert G. Biskeborn, Hugo E. Rothuizen, Calvin S. Lo
  • Patent number: 11037587
    Abstract: An apparatus, according to one embodiment, includes a sensor having an active region, a magnetic shield adjacent the active region, a spacer between the active region and the magnetic shield, a second magnetic shield on an opposite side of the active region as the magnetic shield, and a second spacer between the active region and the second magnetic shield. Both spacers include an electrically conductive ceramic layer. The sensor is an electronic lapping guide.
    Type: Grant
    Filed: January 7, 2020
    Date of Patent: June 15, 2021
    Assignee: International Business Machines Corporation
    Inventors: Robert G. Biskeborn, Calvin S. Lo, Philip M. Rice, Teya Topuria
  • Patent number: 11031031
    Abstract: Provided is a method for forming a tape head module having recessed portion to provide air bearing between a tape medium and a tape bearing surface of the tape head module. A module of the tape head has a first end, a second end opposite the first end, a first side and a second side, opposite the first side, between the first and the second ends, a tape bearing surface and a second surface, opposite the tape bearing surface, between the first end, the second end, the first side, and the second side. Material is removed from the tape bearing surface of the module to form a first recessed portion between the first end and before a region of the tape bearing surface having an array of transducers, and between the first side and the second side.
    Type: Grant
    Filed: May 1, 2018
    Date of Patent: June 8, 2021
    Assignee: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Robert Biskeborn, Calvin S. Lo
  • Patent number: 10984823
    Abstract: An apparatus, according to one embodiment, includes: an array of write transducers. Each of the write transducers include: a first write pole having a pole tip extending from a media facing side of the first write pole, and a second write pole having a pole tip extending from a media facing side of the second write pole. Each of the write transducers also include a nonmagnetic write gap between the pole tips of the write poles, and a first high moment layer between the write gap and the pole tip of the second write pole. The first high moment layer further includes a higher magnetic moment than a magnetic moment of the pole tip of the second write pole. Other systems, methods, and computer program products are described in additional embodiments.
    Type: Grant
    Filed: February 13, 2019
    Date of Patent: April 20, 2021
    Assignee: International Business Machines Corporation
    Inventors: Robert G. Biskeborn, Robert E. Fontana, Jr., Calvin S. Lo
  • Patent number: 10971176
    Abstract: In one general approach, an apparatus includes a sensor having an active tunnel magnetoresistive region, magnetic shields flanking the active tunnel magnetoresistive region, and gaps between the active tunnel magnetoresistive region and the magnetic shields. The active tunnel magnetoresistive region includes a free layer, a tunnel barrier layer and a reference layer. At least one of the gaps includes a seed layer of a chromium alloy and an electrically conductive layer having a refractory material formed on the seed layer. The seed layer in this configuration is more resistant to corrosion than elemental chromium when used in a magnetic recording head and/or in a structure exposed to even trace amounts of fluorine.
    Type: Grant
    Filed: February 21, 2019
    Date of Patent: April 6, 2021
    Assignee: International Business Machines Corporation
    Inventors: Robert G. Biskeborn, Calvin S. Lo, Jason Liang
  • Patent number: 10902868
    Abstract: Provided are a tape head module, tape drive, and method for moving a tape medium over a tape head having a recessed portion to provide air bearing between a tape medium and a tape bearing surface of the module. The tape head includes a tape bearing surface, an array of transducers, including read and/or write transducers, on the tape bearing surface, and a recessed portion formed on the tape bearing surface, wherein the array of transducers is located on the tape bearing surface between the recessed portion and an end of the module to perform read and/or write operations with respect to the tape medium.
    Type: Grant
    Filed: September 24, 2019
    Date of Patent: January 26, 2021
    Assignee: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Robert G. Biskeborn, Calvin S. Lo
  • Patent number: 10839837
    Abstract: A method for measuring a distance between features of a sample, according to one embodiment, includes moving a precision stage having the sample thereon for positioning a first feature of the sample in a field of view of an imaging device. The imaging device is instructed to generate a first image of the first feature of the sample. The sample is moved a defined distance using the precision stage. The imaging device is instructed to generate a second image of a second feature of the sample at the defined distance. The first image and the second image are used to determine an actual distance between the first feature and the second feature. A product, according to one embodiment, includes a thin film structure having a plurality of elements, and at least two features dedicated for enabling measurement therebetween. Each feature is positioned at a known position relative to a respective one of the elements.
    Type: Grant
    Filed: May 22, 2018
    Date of Patent: November 17, 2020
    Assignee: International Business Machines Corporation
    Inventors: Robert G. Biskeborn, Jason Liang, Calvin S. Lo
  • Patent number: 10832721
    Abstract: An apparatus for burnishing media, according to one embodiment, includes a first block with a media bearing surface having a plurality of channels and lands. The channels and lands alternate in a direction of media travel. Each of the lands has at least one skiving edge along a width thereof. The width of each land extends orthogonally to the direction of media travel. The apparatus also includes a mechanism for inducing a wrap angle of the media relative to media bearing surfaces of at least some of the lands. Each induced wrap angle is greater than zero degrees. An apparatus for burnishing media according to another embodiment includes channels having widths that are less than a width of the media.
    Type: Grant
    Filed: April 25, 2018
    Date of Patent: November 10, 2020
    Assignee: International Business Machines Corporation
    Inventors: Robert G. Biskeborn, Gary M. Decad, Jason Liang, Calvin S. Lo
  • Patent number: 10832725
    Abstract: In one embodiment, a computer program product for determining a wrap angle includes a computer readable storage medium having program instructions embodied therewith, wherein the computer readable storage medium is not a transitory signal per se. The program instructions are executable by a processor to cause the processor to perform a method that includes receiving, by the processor, a measurement of a distance from an edge to a transducer, receiving, by the processor, a predefined height of tenting of a magnetic recording tape above the transducer, and determining, by the processor, a wrap angle for inducing tenting of the magnetic recording tape above the transducer at the predefined height when the magnetic recording tape passes over the edge in a direction of tape travel thereacross.
    Type: Grant
    Filed: June 19, 2019
    Date of Patent: November 10, 2020
    Assignee: International Business Machines Corporation
    Inventors: Robert G. Biskeborn, W. Stanley Czarnecki, Calvin S. Lo
  • Patent number: 10832740
    Abstract: In one embodiment, an apparatus includes a module having: an array of transducers formed in thin film structure on a substrate, the array being positioned along a tape bearing surface of the module, and a heating element positioned in the thin film structure and recessed from the tape bearing surface. An apparatus, according to another embodiment, includes a module having an array of transducers formed on a substrate, the array being positioned along a tape bearing surface of the module between skiving edges thereof. A slot is formed in the substrate adjacent one of the skiving edges. A heating element is positioned in the slot.
    Type: Grant
    Filed: October 18, 2018
    Date of Patent: November 10, 2020
    Assignee: International Business Machines Corporation
    Inventors: Robert G. Biskeborn, Calvin S. Lo
  • Patent number: 10818315
    Abstract: An apparatus according to one embodiment includes a magnetic head having at least two tunneling magnetoresistance sensors, where a resistance of a tunnel barrier of each of the tunneling magnetoresistance sensors of the magnetic head is about 25 ohms or less, a drive mechanism for passing a magnetic medium over the magnetic head, and a controller electrically coupled to the magnetic head. In addition, the controller includes a biasing circuit, where the biasing circuit restricts a maximum voltage drop across the tunnel barrier.
    Type: Grant
    Filed: January 9, 2019
    Date of Patent: October 27, 2020
    Assignee: International Business Machines Corporation
    Inventors: Robert G. Biskeborn, W. Stanley Czarnecki, Jason Liang, Calvin S. Lo
  • Patent number: 10803889
    Abstract: An apparatus according to one approach includes a servo reader transducer structure on a module. The servo reader transducer structure has a lower shield, an upper shield above the lower shield, the upper and lower shields providing magnetic shielding, a current-perpendicular-to-plane sensor between the upper and lower shields, an electrical lead layer between the sensor and one of the shields, and a spacer layer between the electrical lead layer and the one of the shields. The electrical lead layer is in electrical communication with the sensor. The conductivity of the electrical lead layer is higher than the conductivity of the spacer layer. An array of writers is also present on the module. Writer modules having this structure are less susceptible to shorting, and therefore enable use of TMR servo readers on writer modules.
    Type: Grant
    Filed: February 21, 2019
    Date of Patent: October 13, 2020
    Assignee: International Business Machines Corporation
    Inventors: Robert G. Biskeborn, Calvin S. Lo
  • Patent number: 10796718
    Abstract: An apparatus, according to one embodiment, includes a first circuit electrically coupled to a first read transducer and a first parallel circuit, the first read transducer having a tunnel valve structure having a resistance. A second circuit is electrically coupled to a second read transducer having a tunnel valve structure. An area of a tunnel barrier portion of the second read transducer along a plane of deposition thereof is larger than an area of a tunnel barrier portion of the first read transducer along a plane of deposition thereof.
    Type: Grant
    Filed: June 26, 2019
    Date of Patent: October 6, 2020
    Assignee: International Business Machines Corporation
    Inventors: Robert G. Biskeborn, Robert E. Fontana, Jr., Calvin S. Lo
  • Publication number: 20200273491
    Abstract: In one general approach, an apparatus includes a sensor having an active tunnel magnetoresistive region, magnetic shields flanking the active tunnel magnetoresistive region, and gaps between the active tunnel magnetoresistive region and the magnetic shields. The active tunnel magnetoresistive region includes a free layer, a tunnel barrier layer and a reference layer. At least one of the gaps includes a seed layer of a chromium alloy and an electrically conductive layer having a refractory material formed on the seed layer. The seed layer in this configuration is more resistant to corrosion than elemental chromium when used in a magnetic recording head and/or in a structure exposed to even trace amounts of fluorine.
    Type: Application
    Filed: February 21, 2019
    Publication date: August 27, 2020
    Inventors: Robert G. Biskeborn, Calvin S. Lo, Jason Liang
  • Publication number: 20200273487
    Abstract: An apparatus according to one approach includes a servo reader transducer structure on a module. The servo reader transducer structure has a lower shield, an upper shield above the lower shield, the upper and lower shields providing magnetic shielding, a current-perpendicular-to-plane sensor between the upper and lower shields, an electrical lead layer between the sensor and one of the shields, and a spacer layer between the electrical lead layer and the one of the shields. The electrical lead layer is in electrical communication with the sensor. The conductivity of the electrical lead layer is higher than the conductivity of the spacer layer. An array of writers is also present on the module. Writer modules having this structure are less susceptible to shorting, and therefore enable use of TMR servo readers on writer modules.
    Type: Application
    Filed: February 21, 2019
    Publication date: August 27, 2020
    Inventors: Robert G. Biskeborn, Calvin S. Lo
  • Patent number: 10755732
    Abstract: An apparatus according to one embodiment includes a module having a plurality of tunnel valve read transducers arranged in an array extending along the tape bearing surface of the module. Each of the tunnel valve read transducers has upper and lower shields for providing magnetic shielding. A sensor structure is positioned between the shields. An electrical lead layer is positioned between the sensor structure and one of the shields. The electrical lead layer is in electrical communication with the sensor structure. A spacer layer is positioned between the electrical lead layer and the one of the shields. A conductivity of the electrical lead layer is higher than a conductivity of the spacer layer. At least some of the sensor structures are recessed from a plane extending along the tape bearing surface. An at least partially polycrystalline coating is positioned on a media facing side of the recessed sensor structures.
    Type: Grant
    Filed: December 12, 2017
    Date of Patent: August 25, 2020
    Assignee: International Business Machines Corporation
    Inventors: Robert G. Biskeborn, Calvin S. Lo
  • Patent number: 10748573
    Abstract: An apparatus according to one embodiment includes a beam and a module coupled to the beam. The module has an array of transducers. A displacement device is positioned between the beam and the module for bending the module, thereby altering a pitch of the transducers. A method according to one embodiment includes applying a control signal to a displacement device positioned between a module having an array of transducers and a beam for bending the module, thereby altering a pitch of the transducers.
    Type: Grant
    Filed: January 14, 2019
    Date of Patent: August 18, 2020
    Assignee: International Business Machines Corporation
    Inventors: Robert G. Biskeborn, Calvin S. Lo, Hugo E. Rothuizen