Space and time averaged values of the atomic oxygen density obtained experimentally for different numbers of driving harmonics, N, and molecular oxygen admixtures for “peaks”-voltage waveforms at fixed z = −15 mm. The base frequency is f0 = 13.56 MHz and the peak-to-peak value of the driving voltage waveform is kept constant at 500 V.
Experimental data are marked as exp
Calculated data are marked as calc
Harmonics used: 1-4
x (N),y (exp mean atomic oxygen densities (cm-3)),

Oxygen admixtures used: 0.05 %(red), 0.1 %(blue), 0.2 %(cyan), 0.4 %(olive green), 0.6 %(dark blue), 0.8 %(green), 1.0 %(orange)