Piezoelectric-Resonance Effect in a Radio-Frequency-Driven Ferroelectric Plasma Source

The effect of driving frequency on the minimum voltage required to form plasma in a radio-frequency ferroelectric plasma source is examined. When the driving frequency of the plasma source is less than the translational effect radial resonant frequency, the applied electric field and background pressure have an increased effect on plasma formation. Applied-voltage frequencies that are close to the radial mechanical resonance of a ferroelectric/piezoelectric disk cause plasma formation to occur at reduced voltages. In one case, a 75% reduction in the breakdown voltage is realized by altering only the frequency of the applied voltage.