Patents by Inventor John G. Forster

John G. Forster 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).

  • Optimized helical resonator for plasma processing
    Patent number: 5241245
    Abstract: An optimized helical resonator which increases the plasma density for efficient processing of semiconductor wafers is characterized by a low inductance and, hence, a low Q. A first embodiment uses either a distributed or lumped capacitance to reduce the value of .omega.L to less than about 200 Ohms. A second embodiment uses a flat spiral coil having a low value of .omega.L and resonant as a 1/4 or 1/2 wave resonator. A third embodiment combines features of the first two embodiments using both spiral and solenoid coils as the helical resonator.
    Type: Grant
    Filed: May 6, 1992
    Date of Patent: August 31, 1993
    Assignee: International Business Machines Corporation
    Inventors: Michael S. Barnes, Dennis K. Coultas, John G. Forster, John H. Keller