Design of an edge tapered 915 MHz/TM021 microwave plasma reactor by numerical analysis

Microwave plasma reactor is often of particular interest due to their wide range of industrial applications, especially in high-end manufacturing. However, there exist problems of unstable plasma and small discharge area in conventional microwave reactors at 2.45 GHz. An edge tapered 915 MHz/TM021 microwave reactor evolved from reactors at 2.45 GHz is presented to improve the strength, area, and uniformity of microwave field for plasma applications. An electromagnetic model of a microwave reactor with the new coupling antenna composed of a tapered platform and a coaxial inner conductor is simulated. The simulation results show that the electric field strength in the new reactor with a size optimized coupling structure is more concentrated compared to similar reactors. A 2D axisymmetric hydrogen plasma discharge model based on self-consistent fluid simulation of this new reactor is presented. The obtained results show that this kind of model can lead to a better understanding of the physical processes occurring in these kinds of microwave reactors.