Quantitative aspects of some unimolecular isomerization reactions of organosilicon intermediates

Understanding the Mechanism of SiC Plasma-Enhanced Chemical Vapor Deposition (PECVD) and Developing Routes toward SiC Atomic Layer Deposition (ALD) with Density Functional Theory

Understanding the mechanism of SiC chemical vapor deposition (CVD) is an important step in investigating the routes toward future atomic layer deposition (ALD) of SiC. The energetics of various silicon and carbon precursors reacting with bare and H-terminated 3C-SiC (011) are analyzed using ab initio density functional theory (DFT). Bare SiC is found to be reactive to silicon and carbon precursors, while H-terminated SiC is found to be not reactive with these precursors at 0 K. Furthermore, the reaction pathways of silane plasma fragments SiH₃ and SiH₂ are calculated along with the energetics for the methane plasma fragments CH₃ and CH₂. SiH₃ and SiH₂ fragments follow different mechanisms toward Si growth, of which the SiH₃ mechanism is found to be more thermodynamically favorable. Moreover, both of the fragments were found to show selectivity toward the Si-H bond and not C-H bond of the surface. On the basis of this, a selective Si deposition process is suggested for silicon versus carbon-doped silicon oxide surfaces.

Shock-tube study of the decomposition of tetramethylsilane using gas chromatography and high-repetition-rate time-of-flight mass spectrometry

The decomposition of tetramethylsilane was studied in shock-tube experiments in a temperature range of 1270–1580 K and pressures ranging from 1.5 to 2.3 bar behind reflected shock waves combining GC/MS and HRR-TOF-MS.

Theoretical calculations on the tetramethyldisilene rearrangement: a new approach to an old mechanistic problem

Roark and Peddle first observed that, when not trapped, Me(2)Si=SiMe(2) underwent a series of rearrangements to give two major isomeric products: 1,1-dimethyl-1,3-disilacyclobutane and 1,3-dimethyl-1,3-disilacyclobutane. The widely accepted mechanism for this rearrangement was proposed by Barton and co-workers. However, little is known about the thermodynamic or kinetic properties of this reaction, because the relevant data are limited to the product ratios of the two isomers. Our calculations predict that the product ratio is driven by kinetic control rather than thermodynamic control. We also show that new DFT functionals, such as MPW1K and M052X, produce thermochemical results comparable with CCSD(T) calculations.