Fig. 2

Plasma chemistry pictured in a 3D plot. 3D area showing the behavior of the C₂/Hα-ratio as a function of the applied pressure and the methane ratio in the gas mixture. The microwave power is held at a constant value of 1 kW for all measuring points depicted. The bullet points are the measured values for pressures between 20 and 80 mbar and methane ratios in the gas of between 5 and 30 % respectively. The grey leveled area is a logistic fit of the total amount of measured values