Study On The Characteristics Of Low-power Microwave Microplasma Based On Microstrip Split-ring Resonator

In recent years, research on microwave microplasma source has become a hot spot which can be integrated in the micro-electromechanical systems (MEMS). It is a high-tech including microwave technology and plasma technology. Compared with other plasma source, the microwave microplasma source is characteristic of small size, computability, long life and low pollution, and has potential applications on micro-chemical analysis system, biological MEMS sterilization, small-scale materials processing, micro thrusters and particle detection.A kind of microstrip split-ring resonator with round-edge gap and the dielectric substrate made of alumina ceramic is selected in the thesis, and the characteristics of the capacitively-coupled microwave microplasma are studied. Firstly, the theories of plasma and microstrip split-ring resonator are introduced, and microplasma impedance, reflection coefficient and microwave ignition power with a permanent magnet are discussed.Secondly, the characteristics of the low-power microwave microplasma are analyzed at different air pressure (3.0Torr,3.7Torr and5.0Torr) and different magnetic field strength (360G,990G and2840G), including microwave microplasma excitation, S-parameter, temperature and spectrum.Finally, the preliminary experimental results show that microwave ignition power is regular with air pressure; it is easier for low-power microwave microplasma source with magnet to ignite microwave microplasma than without magnet; the magnet pole also has an impact on microplasma excitation. The study provides the basis for further miniaturization of low-power microwave plasma source.