Patents by Inventor Wee-chen Richard Gan

Wee-chen Richard Gan 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: 7070484
    Abstract: A chemical mechanical polishing (CMP) method is disclosed in which a new polishing pad is broken-in and conditioned into a steady operating state while using a silica (SiO2) based CMP slurry and where the broken-in and conditioned pad is afterwards used for polishing patterned workpieces (e.g., semiconductor wafers) with a ceria (CeO2) based CMP slurry. The approach shortens break-in time and appears to eliminate a first wafer effect usually seen following break-in with ceria-based CMP slurries.
    Type: Grant
    Filed: May 21, 2004
    Date of Patent: July 4, 2006
    Assignee: Mosel Vitelic, Inc.
    Inventors: Kuo-Chun Wu, Wee-chen Richard Gan, Karen Wong
  • Patent number: 7040958
    Abstract: A chemical mechanical polishing (CMP) method is disclosed in which a torque-based end-point algorithm is used to determine when polishing should be stopped. The end-point algorithm is applicable to situations where a ceria (CeO2) based CMP slurry is used for further polishing, pre-patterned and pre-polished workpieces (e.g., semiconductor wafers) which have a high friction over-layer (e.g., HDP-oxide) and a comparatively, lower friction and underlying layer of sacrificial pads (e.g., silicon nitride pads). A mass production wise, reliable and consistent signature point in the friction versus time waveform of a torque-representing signal is found and used to trigger an empirically specified duration of overpolish. A database may be used to define the overpolish time as a function of one or more relevant parameters.
    Type: Grant
    Filed: May 21, 2004
    Date of Patent: May 9, 2006
    Assignee: Mosel Vitelic, Inc.
    Inventors: Wee-chen Richard Gan, Karen Wong, Kuo-Chun Wu