Numerical modeling of gas-phase reactions of tetraethoxysilane/O2/Ar atmospheric dielectric barrier discharge for deposition

A chemical kinetic model is developed to study the decomposition of tetraethoxysilane (TEOS) in O-2/Ar atmospheric pressure dielectric barrier discharge and compared with gas chromatography and optical emission spectroscopy results. The calculations indicate that the excited Ar dominates the fragmentation of TEOS in the absence of oxygen and mainly breaks the carbon-carbon bonds in TEOS. However, in the presence of oxygen, the primary decomposition process of TEOS is the substitution of ethoxy (-OC2H5) by hydroxyl (-OH). The variation of these two reactions with oxygen composition could explain the transition of the deposition layer from organic to norganic. The model and its results provide a theoretical basis for further modeling and regulating the quality of the deposition layer.