Microwave atmospheric discharge for materials processing

Summary form only given. Microwave atmospheric plasma system using TM₀₁₁ mode is successfully designed and built for materials processing applications. The microwave applicator and chamber were specifically designed to maximize microwave coupling into the plasma at resonant frequency. The system consists of a magnetron power supply, a circulator, a directional coupler, a three-stub tuner, a dummy load, a coaxial cavity, and a central cavity. Azimuthal slots were placed between the coaxial and the central cavity for efficient magnetic coupling. The plasma was reliably sustained at atmospheric pressure with good uniformity. Design and construction of the plasma system and diagnostics of atmospheric pressure plasma are presented for various ranges of pressure and gas types.