Tetrachlorosilane Consumption in Radio Frequency Glow Discharge

Time-resolved mass spectrometry was used for analysis of the plasma reactions in radio frequency (RF) SiCl₄and SiCl₄–O₂discharges as functions of starting partial pressure and electrical power. Molecular concentrations of the reactants and products from SiCl₄alone and with O₂were obtained from the mass spectra and used for plotting the kinetic curves. The SiCl₄and O₂consumption rates were calculated from the kinetic curves and compared with results of theoretical simulation of the reaction. Direct electron impact decomposition was found to be the main pathway for pure SiCl₄conversion. On the contrary, the consumption of SiCl₄in the SiCl₄+O₂mixtures was largely chemical. The experimental macrokinetics are in agreement with a model in which oxidation is caused by the atomic oxygen.