Improve the Stability of Atmospheric Microwave Plasma by Gas-flow Control

Microwave atmospheric pressure discharge in a coaxial structure generator fed by 200W 2.45GHz microwave power with Argen(Ar)-Hydrogen(H-2) gas combination was studied. In this study, a coaxial structured microwave plasma generator was employed to produce plasma, and two-way gas flow was used to reduce airflow and to improve plasma stability. Combined with the gas-flow simulation, the morphology of plasma and its reflected microwave power has shown that the airflow of Ar in central conductor 1000sccm used as the working gas and H-2 ia side path 200sccm used as the protective gas could sustain the plasma well. Furthermore, we have analyzed the effect of H-2 on the plasma front the perspective of ionization energy.