Computational Study for Reactions of H Atoms with Adsorbed SiH3 and Si2H5 on H-Covered Si(100)-(2 脳 1) Surface

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• 作者：Hsin-Tsung Chen ; Hsien-Wei Huang
• 刊名：Journal of Physical Chemistry C
• 出版年：2014
• 出版时间：September 4, 2014
• 年：2014
• 卷：118
• 期：35
• 页码：20314-20322
• 全文大小：468K
• ISSN：1932-7455

文摘

Density functional theory calculations with spin-polarization effect were employed to illustrate the adsorption of Si_xH_y (x = 1鈥?; y = 1鈥?) species and the reactions of H atoms with adsorbed SiH_x (x = 1鈥?) and Si₂H₅ species on the H-covered Si(100)-(2 脳 1) surface. The configurations and energies of these adsorbates were elucidated. It was found that H vacancy sites can be easy created by SiH₃ and Si₂H₅ radicals with small barriers (2.1 and 1.6 kcal/mol for SiH₃ and Si₂H₅, respectively). The Si₂H₅, Si₂H₄, SiHSiH₃, SiH₃, SiH₂, SiH, and Si radials interact with the surface more forcefully than the Si₂H₆ and SiH₄ molecules. Potential energy surfaces for the reaction mechanisms of H + SiH_x(a) and H + Si₂H₅(a) were mapped by using the nudged elastic band method. The calculation results demonstrate that the most favorable pathway is hydrogen abstraction leading to the production of H₂ and Si_xH_y (x = 1鈥?; y = 0鈥?) because of their low barriers and high exothermicities. Rate constant calculations were performed to study the kinetic behavior for simulation of silicon thin-film growth by chemical vapor deposition processes.