## 摘要

Gas-phase kinetics and mechanisms of SiH_{3} reactions with SiH_{4}, Si_{2}H_{6}, Si_{3}H_{8}, and Si_{4}H_{10}, processes of relevance to a-Si thin-film deposition, have been investigated by ab initio molecular orbital and transition-state theory (TST) calculations. Geometric parameters of all the species involved in the title reactions were optimized by density functional theory at the B3LYP and BH&HLYP levels with the 6-311++G(3df,2p) basis set. The potential energy surface of each reaction was refined at the CCSD(T)/6-311++G(3df,2p) level of theory. The results show that the most favorable low energy pathways in the SiH_{3} reactions with these silanes occur by H abstraction, leading to the formation of SiH_{4} + Si_{x}H_{2x+1} (silanyl) radicals. For both Si_{3}H _{8} and n-Si_{4}H_{10} reactions, the lowest energy barrier channels take place by secondary Si-H abstraction, yielding SiH _{4} + s-Si_{3}H_{7} and SiH_{4} + s-Si _{4}H_{9}, respectively. In the i-Si_{4}H_{10} reaction, tertiary Si-H abstraction has the lowest barrier producing SiH _{4} + t-Si_{4}H_{9}. In addition, direct SiH _{3}-for-X substitution reactions forming Si_{2}H_{6} + X (X = H or silanyls) can also occur, but with significantly higher reaction barriers. A comparison of the SiH_{3} reactions with the analogous CH_{3} reactions with alkanes has been made. The rate constants for low-energy product channels have been calculated for the temperature range 300-2500 K by TST with Eckart tunneling corrections. These results, together with predicted heats of formation of various silanyl radicals and Si _{4}H_{10} isomers, have been tabulated for modeling of a-Si:H film growth by chemical vapor deposition.

原文 | English |
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頁（從 - 到） | 13353-13361 |

頁數 | 9 |

期刊 | Journal of Physical Chemistry A |

卷 | 114 |

發行號 | 51 |

DOIs | |

出版狀態 | Published - 30 12月 2010 |

## 指紋

深入研究「Ab initio chemical kinetics for SiH_{3}reactions with Si

_{x}H

_{2x+2}(x = 1-4)」主題。共同形成了獨特的指紋。