COMPARATIVE STUDY OF PLASMA PARAMETERS AND COMPOSITIONS IN CF4, Cl2 AND HBr + Ar GAS MIXTURES
Abstract
This work discusses the plasma characteristics and chemistry in CF4 + Ar, Cl2 + Ar and HBr + Ar gas systems under one and the same operating condition. The investigation was carried out using the combination of plasma diagnostics by Langmuir probes and 0-dimensional plasma modeling in the planar inductively coupled plasma reactor at constant gas pressure (10 mTorr), input power (800 W) and bias power (300 W), but with variable (0–80%) Ar fraction in a feed gas.The main attention was attracted to the parameters influencing the steady-state densities of plasma active species (electron temperature, electron density, electron-impact rate coefficients) and the kinetics of ion-assisted chemical reaction (fluxes of halogen atoms, ion bombardment energy, ion energy flux).
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