Patents by Inventor Yu C. Douglas

Yu C. Douglas 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).

  • Process to minimize a seam in tungsten filled contact holes
    Patent number: 5622894
    Abstract: A process has been developed in which high aspect ratio contact holes, are filled with chemically vapor deposited tungsten plugs, exhibiting little or no seam at the center of the tungsten plug. The process features protection of the tungsten plug from the final removal and overetch steps, needed to remove residual tungsten from areas outside the contact hole. This is accomplished by delaying the residual removal procedure, until the tungsten plug is protected by an overlying interconnect metallization structure.
    Type: Grant
    Filed: March 15, 1996
    Date of Patent: April 22, 1997
    Assignee: Taiwan Semiconductor Manufacturing Company Ltd
    Inventors: Syun-Ming Jang, Yu C. Douglas