Patents by Inventor Eehern Wong

Eehern Wong 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: 20070251939
    Abstract: The present invention relates generally to control schemes for controlling the temperature of a heater plate of a thermal unit, e.g., of a track lithography tool. In accordance with certain embodiments of the invention, a cold wafer compensation offset value is added to an initial target heater plate temperature setpoint, and this setpoint plus offset is used to control the temperature of the heater plate prior to placement of a semiconductor wafer, e.g., via Proportional-Integral-Derivative (PID) control. Further, in accordance with certain embodiments, upon cold wafer placement, the temperature control is turned off until the temperature of the heater plate reaches the initial target heater plate temperature setpoint. The temperature control (e.g., PID control) is then reinstated, and the heater plate and wafer are controlled to steady state.
    Type: Application
    Filed: April 27, 2006
    Publication date: November 1, 2007
    Applicant: Applied Materials, Inc.
    Inventors: Alex Minkovich, Natarajan Ramanan, Eehern Wong