Patents by Inventor Hong Ho-Cheng

Hong Ho-Cheng 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).

  • Method for monitoring polishing pad used in chemical-mechanical planarization process
    Patent number: 6194231
    Abstract: A method for monitoring a condition of a polishing pad used in a chemical-mechanical planarization (CMP) process to polish a semiconductor wafer is disclosed. The method uses a linear multi-dimensional scanning device arranged above the polishing pad in a radial direction to monitor the changes in profile of the surface of the polishing pad, and determines the condition of the polishing pad according to the profile information. When the change in profile of the surface of the polishing pad substantially exceeds a preset value, e.g. 2 mm, it is indicated that the polishing pad should be changed.
    Type: Grant
    Filed: March 1, 1999
    Date of Patent: February 27, 2001
    Assignee: National Tsing Hua University
    Inventors: Hong Ho-Cheng, Kuo-Hsing Liu