Fast transition RF impedance matching network for plasma reactor ignition

摘要

An impedance matching network for an RF coupled plasma reactor having RF excitation apparatus receiving RF power through the impedance matching network from an RF generator for producing a plasma in the reactor has at least one capacitor connected to the output of the RF generator and having a capacitance value providing an impedance match to the plasma impedance during a steady state of the plasma, at least a first rapidly tunable capacitor connected in parallel with the one capacitor, the rapidly tunable capacitor being rapidly switchable between a high capacitance value providing a match to the plasma impedance during the onset of plasma ignition and a lesser minimum capacitance value, and a controller for rapidly switching the rapidly tunable capacitor from the high to the lesser capacitance value upon reaching the plasma steady state.