Patent ID: 6291938
Filing Date: 2001-09-18
Classification: H01J

Abstract:
An apparatus for generating plasma in a gas for plasma processing using inductively coupled RF power, the apparatus comprising:an RF power source;an RF power induction coil having a resonant section, the resonant section comprising at least a tenth of a coil turn the resonant section being connected with the RF power source for receiving RF power, the resonant section being disposed so as to couple RF power to the gas;at least one nonresonant section, the nonresonant section being electrically conductive, the nonresonant section being electrically connected with a location on the resonant section; andwhereby, a substantially constant input of RF power to the resonant section of the RF coil, in the absence of the plasma, causes the at least one nonresonant section to maintain voltages that create an enhanced electric field in the gas so that the enhanced electric field facilitates igniting the plasma, and, when the plasma is present, the input of RF power causes the at least one nonresonant section to maintain lower voltages and the plasma is sustained by inductive coupling of RF power from the resonant section.