Patents by Inventor Angelo R. Tretola

Angelo R. Tretola 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 of controlling a plasma etching process by monitoring the impedance changes of the RF power
    Patent number: 4207137
    Abstract: A plasma etching process wherein the end point of the reaction can be accurately determined for fine line definition. This is accomplished by monitoring the impedance of the plasma during the reaction. The reaction is stopped at, or a predetermined time after, the change in impedance reaches a zero value, which is either a maximum or minimum depending upon the gases utilized.
    Type: Grant
    Filed: April 13, 1979
    Date of Patent: June 10, 1980
    Assignee: Bell Telephone Laboratories, Incorporated
    Inventor: Angelo R. Tretola