Patents by Inventor Robert L. Duffin

Robert L. Duffin 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: 5700721
    Abstract: A metallization alloy for semiconductor devices comprising aluminum, copper, and tungsten is provided. In a method for applying the metallization, the metal is sputtered onto a semiconductor substrate having devices formed therein. After deposition, the metallization is patterned and etched using conventional semiconductor photoresist and etch techniques.
    Type: Grant
    Filed: June 4, 1996
    Date of Patent: December 23, 1997
    Assignee: Motorola, Inc.
    Inventors: Hank Hukyoo Shin, Clarence J. Tracy, Robert L. Duffin, John L. Freeman, Jr., Gordon Grivna, Syd R. Wilson
  • Patent number: 5554889
    Abstract: A metallization alloy for semiconductor devices comprising aluminum, copper, and tungsten is provided. In a method for applying the metallization, the metal is sputtered onto a semiconductor substrate having devices formed therein. After deposition, the metallization is patterned and etched using conventional semiconductor photoresist and etch techniques.
    Type: Grant
    Filed: April 27, 1995
    Date of Patent: September 10, 1996
    Assignee: Motorola, Inc.
    Inventors: Hank H. Shin, Clarence J. Tracy, Robert L. Duffin, John L. Freeman, Jr., Gordon Grivna, Syd R. Wilson
  • Patent number: 5049811
    Abstract: A fast, nondestructive, and low cost method for measuring the integrity of semiconductor multi-layer conducting structures uses a voltage spectral density technique. The method compares the magnitude and frequency of generally non-periodic low frequency voltages induced by direct current flow in test structures to the same parameters of a defect free structure.
    Type: Grant
    Filed: July 2, 1990
    Date of Patent: September 17, 1991
    Assignee: Motorola, Inc.
    Inventors: Michael Dreyer, Robert L. Duffin
  • Patent number: 4970176
    Abstract: Metal step coverage is improved by utilizing a multiple step metallization process. In the first step, a thick portion of a metal layer is deposited on a semiconductor wafer at a cold temperature. The remaining amount of metal is deposited in a second step as the temperature is ramped up to allow for reflow of the metal layer through grain growth, recrystallization and bulk diffusion. The thick portion of the metal layer deposited at the cold temperature is of adequate thickness so that it remains continuous at the higher temperature and enhances via filling.
    Type: Grant
    Filed: September 29, 1989
    Date of Patent: November 13, 1990
    Assignee: Motorola, Inc.
    Inventors: Clarence J. Tracy, John L. Freeman, Jr., Robert L. Duffin, Anthony Polito