Patents by Inventor Thomas C. Anthony

Thomas C. Anthony 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: 5216560
    Abstract: A magnetoresistive sensor having a longitudinal field that is produced along its axis and that stabilizes the sensor. The longitudinal field is produced by the current in conductors that are connected to the magnetoresistive sensor elements. By controlling the direction and distribution of the current in the conductors, a longitudinal field is produced that has the required direction and magnitude to stabilize the single domain state of the sensor. The resulting lack of domain wall motion in the sensor during operation prevents instabilities in its electrical output, commonly known as Barkhausen noise. Four different sensor designs are provided that include two single element sensors with two conductors, a dual element sensor with four conductors, and a dual element sensor with three conductors. The ease of implementation makes the stabilized sensor of the present invention superior to conventional approaches that rely on permanent magnets or exchange coupled layers to provide longitudinal bias.
    Type: Grant
    Filed: September 19, 1991
    Date of Patent: June 1, 1993
    Assignee: Hewlett-Packard Company
    Inventors: James A. Brug, Thomas C. Anthony
  • Patent number: 4933209
    Abstract: A thin film recording head which utilizes polyimide as the coil encapsulant. The polyimide encapsulant is self planarizing and lends itself to processing of the coil vias, magnetic shunt vias and apex tapers. Methods of fabricating a thin film recording head and forming coil vias, magnetic shunt vias and apex tapers are also disclosed. In general, an insulating material is deposited on a bottom magnetic yoke. A first layer of polyimide is then deposited of the insulating material. Then, a three layer photoresist structure is deposited on the first layer of polyimide, which includes a transfer layer deposited between two layers of photoresist. The top layer of photoresist is developed and the transfer layer is etched. The first layer of photoresist is then etched into the polyimide layer to form troughs therein. The coil material is then deposited into the etched troughs. The coil material comprises a layer of metal having a relatively thin passivation layer deposited thereover.
    Type: Grant
    Filed: June 28, 1989
    Date of Patent: June 12, 1990
    Assignee: Hewlett-Packard Company
    Inventors: Thomas C. Anthony, Steven L. Naberhuis, Robert A. Garcia, Hardayal S. Gill
  • Patent number: 4853080
    Abstract: A lift-off process for patterning bottom shields used in thin film magnetic recording heads. The lift-off process comprises the steps of depositing a first layer of resist material (22) on a substrate (20) and hard baking the resist material (22). A transfer layer (24) is deposited over the first layer of resist material (22) and a second layer of resist material (26) is deposited on top of the transfer layer (24). The second layer of resist material (24) is then patterned and developed. The patterned structure is then etched to form a mask structure wherein the transfer layer (24) overhangs the first layer of resist material (22). An adhesion layer (30) and an amorphous magnetic alloy material (32) are then sequentially deposited on the exposed surface of the substrate (20). The amorphous magnetic alloy material (32) is sputter deposited at a pressure of about 3.4 mT, a condition that resists the stress in the amorphous alloy material to less than 10.sup.9 dynes per square centimeter.
    Type: Grant
    Filed: December 14, 1988
    Date of Patent: August 1, 1989
    Assignee: Hewlett-Packard
    Inventor: Thomas C. Anthony