Patents by Inventor David P. Maddex

David P. Maddex 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).

  • Alumina material useful with thin film heads
    Patent number: 5357389
    Abstract: A process for sputtering and depositing sputtered alumina uses a mixture of two gases, preferably argon and air, for the deposition phase. No external heat is supplied to the sputtering system during the presputtering, sputter etch and deposition phases of the process. The alumina that is produced is crypto-crystalline and is characterized by crystal size of less than one micron. The alumina is very hard, impervious to attack by acid or base solutions and has improved machining qualities. The alumina is useful as a transducing gap layer in a thin film magnetic head.
    Type: Grant
    Filed: August 2, 1993
    Date of Patent: October 18, 1994
    Assignee: Read-Rite Corporation
    Inventors: Curtis N. Blanchette, David P. Maddex, Richard F. Shimek
  • Alumina material useful with thin film heads
    Patent number: 5256266
    Abstract: A process for sputtering and depositing sputtered alumina uses a mixture of two gases, preferably argon and air, for the deposition phase. No external heat is supplied to the sputtering system during the presputtering, sputter etch and deposition phases of the process. The alumina that is produced is crypto-crystalline and is characterized by crystal size of less than one micron. The alumina is very hard, impervious to attack by acid or base solutions, and has improved machining qualities. The alumina is useful as a transducing gap layer in a thin film magnetic head.
    Type: Grant
    Filed: October 31, 1991
    Date of Patent: October 26, 1993
    Assignee: Read-Rite Corporation
    Inventors: Curtis N. Blanchette, David P. Maddex, Richard F. Shimek