Frequency of Power Source

The glow discharge initiated by an AC power source can be visualized by an alternating cathode and anode in the DC glow discharge, up to a certain frequency. 

At a higher frequency (e.g., more than 100 kHz), an electron can no longer travel the distance to reach the anode before the polarity changes depending on the 

Because of the oscillation of electrons rather than linear motion, the influence of magnetic field imposed by the magnetrons also diminishes. Thus, the predominant role of the cathode observed in DC and AC discharge diminishes in 13.5-MHz discharge. The deposition rate characteristics (on electrode surface), i.e., the system pressure dependence and the refractive index of the deposit, are completely different from those for DC or 40-kHz discharge [1]. 

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