Rate coefficients for elementary reactions connected to the potential energy wells of SiHCl 3 , SiH 2 Cl 2 , SiHCl 2 , and SiH 3 Cl, which are important Si 1 species in chemical vapor deposition (CVD) processes that use chlorosilanes as silicon source gases, were determined through Rice-Ramsperger-Kassel-Marcus (RRKM) theory for various conditions of temperature and pressure. Many of the unimolecular decomposition channels and chemical activation reactions investigated in this work were found to be in the fall-off regime under subatmospheric to moderately high-pressure conditions, so that it is expected that accurate modeling of the gas phase in chlorosilane CVD reactors requires careful determination of the rate coefficients as functions of temperature and pressure for the conditions of interest, instead of using high-pressure limit rate coefficients. The rate coefficients determined here were tabulated using Chebyshev coefficients and can be used in simulations of systems under a wide range of temperature and pressure conditions. K E Y W O R D Sab initio calculations, chemical vapor deposition, chlorosilane, gas-phase kinetics, Rice-Ramsperger-Kassel-Marcus calculationsThis is an open access article under the terms of the Creative Commons Attribution-NonCommercial-NoDerivs License, which permits use and distribution in any medium, provided the original work is properly cited, the use is non-commercial and no modifications or adaptations are made.

Rate coefficients for elementary reactions connected to the potential energy wells of Si2H2Cl4, Si2Cl6, and Si2Cl4, which are important Si2 species in chemical vapor deposition (CVD) processes that use chlorosilanes as silicon source gases, were determined through the Rice–Ramsperger–Kassel–Marcus theory under various conditions of temperature and pressure. The optimized structures and vibrational frequencies of the reactants, products, and transition state were obtained using (U)B3LYP/6-31+G(d,p), and the single-point energies of the optimized structures were recalculated using the coupled cluster method with single and double excitations plus triple perturbation (U)CCSD(T) with complete basis set extrapolation. Many of the unimolecular decomposition channels and chemical activation reactions investigated in this work were found to be in the fall-off regime under subatmospheric to moderately high-pressure conditions so that it is expected that accurate modeling of the gas phase in the chlorosilane CVD reactor requires careful determination of the rate coefficients as functions of temperature and pressure for the conditions of interest, instead of using high-pressure limit rate coefficients. The rate coefficients determined here were expressed through Chebyshev coefficients and also modified Arrhenius parameters to be used in simulations of systems under a wide range of temperature and pressure conditions.

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