Patents by Inventor Andrew J. Nagengast

Andrew J. Nagengast 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).

  • Publication number: 20020081956
    Abstract: A carrier head for chemical mechanical polishing that has a base having at least a portion formed of a polymer, a mounting assembly connected to the base having a surface for contacting a substrate, a retainer secured to the portion of the base to prevent the substrate from moving along the surface, and a dampening material secured between the retainer and the base.
    Type: Application
    Filed: October 10, 2001
    Publication date: June 27, 2002
    Applicant: Applied Materials, Inc.
    Inventors: Doyle E. Bennett, Andrew J. Nagengast, Hung Chih Chen
  • Patent number: 6325706
    Abstract: A technique for utilizing a sensor to monitor fluid pressure from a fluid bearing located under a polishing pad to detect a polishing end point. A sensor is located at the leading edge of a fluid bearing of a linear polisher, which is utilized to perform chemical-mechanical polishing on a semiconductor wafer. The sensor monitors the fluid pressure to detect a change in the fluid pressure during polishing, which change corresponds to a change in the shear force when the polishing transitions from one material layer to the next. In order to ensure that there is a noticeable difference in the shear force variation at the polishing end point, a slurry having a particular pH level is selected. The pH level ensures that the zeta potential changes noticeably from one material to the next, so as to induce a change in the shear force, which is detected by a change in the fluid pressure.
    Type: Grant
    Filed: October 29, 1998
    Date of Patent: December 4, 2001
    Assignee: Lam Research Corporation
    Inventors: Wilbur C. Krusell, Andrew J. Nagengast, Anil K. Pant
  • Patent number: 6186865
    Abstract: A technique for utilizing a sensor to monitor fluid pressure from a fluid bearing located under a polishing pad to detect a polishing end point. A sensor is located at the leading edge of a fluid bearing of a linear polisher, which is utilized to perform chemical-mechanical polishing on a semiconductor wafer. The sensor monitors the fluid pressure to detect a change in the fluid pressure during polishing, which change corresponds to a change in the shear force when the polishing transitions from one material layer to the next.
    Type: Grant
    Filed: October 29, 1998
    Date of Patent: February 13, 2001
    Assignee: Lam Research Corporation
    Inventors: Brian Thornton, Andrew J. Nagengast, Robert G. Boehm, Jr., Anil K. Pant, Wilbur C. Krusell