Axial Density Profile of 27 Mhz Capacitively Coupled Rf Plasma; Power and Pressure Dependence

Abstract

Axial density profiles of Confined Capacitively Coupled Plasma (CCCP) are measured for different pressure and power levels with a microwave interferometer. Abel inversion is used to deduce radial density profiles, which show that density diffuses from center to the quartz tube walls and indicate different density profiles depending on the pressure and power. The preheat like potential drop from center to close to the boundary edge is approximately twice the electron temperature, while the density drops approximately five to eight times

Keywords

• Plasma density, Microwave interferometer, Confined Capacitively Coupled Plasma, Pre-sheath

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