Patent ID: 6388226
Filing Date: 2002-05-14
Classification: H01J

Abstract:
An apparatus for dissociating gases in a plasma comprising:a) a plasma chamber; b) a transformer having a primary winding and having a magnetic core surrounding a portion of the plasma chamber; c) a switching power supply in electrical communication with the primary winding; d) a resonance capacitor in electrical communication with the primary winding and the switching power supply, the resonance capacitor and the switching power supply forming a resonant circuit at switching frequency of the switching power supply, the resonant circuit outputting a resonance voltage on the primary winding; and e) an electronic control circuit in electrical communication with the primary winding and the switching power supply; wherein the control circuit maintains current in the primary winding at a first value while the resonance voltage is on the primary winding, adjusts current in the primary winding to a second value upon ignition of a plasma in the chamber, and raises current in the primary winding to a third value subsequent to switching off of the resonant circuit from the primary winding, thereby controlling ignition of the plasma.