@article{4b53df7a79124ecfaeb683ca80929c70,

title = "Ab Initio Chemical Kinetics for the Thermal Decomposition of SiH4 + Ion and Related Reverse Ion–Molecule Reactions of Interest to PECVD of a-Si:H Films",

abstract = "The thermal unimolecular decomposition of SiH4 + ion and its related reverse reactions, SiH3 + + H and SiH2 + + H2, have been investigated by ab initio molecular orbital and quantum statistical variational RRKM theory calculations. The potential energy surface has been calculated at different levels of theory; the results at the highest level, CCSD(T)/CBS//CCSD(T)/6-311++G(3df,2p), show that the decomposition of SiH4 + can mainly occur via a barrierless channel giving SiH2 + + H2 lying 11.8 kcal/mol above the reactant, or via a transition state forming SiH3 +···H complex to be followed by a barrierless decomposition yielding SiH3 + + H lying 23.5 kcal/mol above the reactant. Barrierless processes were calculated using the CASPT2 and CASSCF methods with the 6-311++G(3df,2p) basis set and fitted with Morse potentials. The rate constants were predicted by solving master equations based on the RRKM theory at the E,J-resolved level; the results show that the channel SiH4 + → SiH2 + + H2 is predominate under PEVCD conditions. For H- and H2-capturing by SiH3 + and SiH2 + ions, respectively, the rate constants were found to be weakly dependent on temperature at the high-pressure limit and decrease rapidly with pressure. The calculated heats of formation of the SiHx + (x = 2–4) ions are in close agreement with available thermochemical data.",

keywords = "Kinetics, Mechanism, PECVD, SiH, Silicon thin film",

author = "Nguyen, {T. N.} and Lee, {Y. M.} and Jong-Shinn Wu and Ming-Chang Lin",

note = "Publisher Copyright: {\textcopyright} 2017, Springer Science+Business Media New York.",

year = "2017",

month = jul,

day = "1",

doi = "10.1007/s11090-017-9825-7",

language = "English",

volume = "37",

pages = "1249--1264",

journal = "Plasma Chemistry and Plasma Processing",

issn = "0272-4324",

publisher = "Springer New York",

number = "4",

}