Plasma treatment equipment, power supply system, and source frequency control methods

Abstract

The plasma processing apparatus disclosed in this invention includes an RF generation unit for plasma generation. In the RF generation unit, a phase difference detector generates a voltage corresponding to the phase difference between a first signal and a second signal for each phase within a repetition period. The first signal and the second signal are the voltage and current of a source RF signal, or the traveling wave and reflected wave of the source RF signal. A voltage-controlled oscillator generates a signal having a source frequency corresponding to the voltage generated by the phase difference detector. An amplifier amplifies the signal generated by the voltage-controlled oscillator to generate source RF signals for each phase within the repetition period. A delay circuit outputs the source RF signals for each phase within the repetition period from the RF generation unit after delaying the source RF signals for each phase by an integer multiple of the repetition period's duration.

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