Experimental study of the plasma resonance in a planar surface wave plasma

Abstract

In this study, the plasma resonance in a surface wave sustained plasma was investigated. Surface wave discharges have been successfully generated by a microwave planar vane-type slow wave structure. Experimental results clearly demonstrated that the amplitude of the electric field of the microwave always became a local maximum in the position where the plasma density was equal to the same value. When the operating gas pressure and the input microwave power were varied to change the plasma density profile, the location of the maximum of the electric field was found to shift in compliance with the plasma density profile. Meanwhile, the peak of the resonance response was found to be proportional to the plasma density gradient while the spatial width of plasma resonance was inversely proportional to the plasma density gradient. These results were qualitatively in accordance with the theory.