FOCUS RING ARRANGEMENT FOR SUBSTANTIALLY ELIMINATING UNCONFINED PLASMA IN A PLASMA PROCESSING CHAMBER

摘要

A FOCUS RING ASSEMBLY CONFIGURED TO SUBSTANTIALLY ENCIRCLE A CHUCK OF A PLASMA PROCESSING CHAMBER. THE FOCUS RING ASSEMBLY INCLUDES AN ANNULAR DIELECTRIC BODY; AND AN ELECTRICALLY CONDUCTIVE SHIELD SURROUNDING THE ANNULAR DIELECTRIC BODY. THE ELECTRICALLY CONDUCTIVE SHIELD IS CONFIGURED TO BE ELECTRICALLY GROUNDED WITHIN THE PLASMA PROCESSING CHAMBER AND INCLUDES A TUBE-SHAPED PORTION BEING DISPOSED OUTSIDE OF THE ANNULAR DIELECTRIC BODY AND SURROUNDING AT LEAST PART OF THE ANNULAR DIELECTRIC BODY. THE ELECTRICALLY CONDUCTIVE SHIELD FURTHER INCLUDES AN INWARDLY-PROTRUDING FLANGE PORTION BEINGIN ELECTRICAL CONTACT WITH THE TUBE-SHAPED PORTION. THE FLANGE PORTION FORMS BEING IN ELECTRICAL CONTACT WITH THE TUBE-SHAPED PORTION. THE FLANGE PORTION IS EMBEDDED WITHIN THE ANNULAR DIELECTRIC BODY. (FIG 3)