Patents by Inventor Charles C. Leung

Charles C. Leung 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: 4672023
    Abstract: A method for filling indentations to planarize the surface of a wafer is disclosed. The method includes three steps: (1) coating the wafer surface with a layer of positive photoresist that fills the indentations and covers the surface of the wafer; (2) exposing the layer of photoresist to light or other radiation source of such intensity and duration that the layer of photoresist is exposed down to the surface of the wafer but not into the indentations; and (3) removing the exposed portion of the photoresist by using a developer, resulting in a planarized wafer containing indentations filled with unexposed photoresist. Once the wafer has been planarized by this method, overstructures can be formed over the top of the photoresist filled indentations.
    Type: Grant
    Filed: October 21, 1985
    Date of Patent: June 9, 1987
    Assignee: Avantek, Inc.
    Inventor: Charles C. Leung