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Si + SiH4 Reactions and Implications for Hot-Wire CVD of a-Si:H: Computational Studies

Published online by Cambridge University Press:  17 March 2011

Richard P. Muller
Affiliation:
Materials and Process Simulation Center
Jason K. Holt
Affiliation:
Department of Chemical Engineering
David G. Goodwin
Affiliation:
Division of Engineering and Applied Science, California Institute of Technology, Pasadena, California, 91125
William A. Goddard III
Affiliation:
Division of Engineering and Applied Science, California Institute of Technology, Pasadena, California, 91125
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Abstract

Gas phase chemistry is believed to play an important role in hot-wire CVD of amorphous silicon, serving to convert the highly-reactive atomic Si produced at the wire into a less-reactive species by reaction with ambient SiH4. In this paper, we use quantum chemistry computations (B3LYP/cc-pvTZ) to examine the energetics and rates of possible gas-phase reactions between Si and SiH4. The results indicate that formation of disilyne (Si2H2) is energetically favorable. Unlike other products of this reaction, Si2H2 does not require collisional stabilization, and thus this species is the most likely candidate for a benevolent precursor that participates in the growth of high-quality Si films.

Type
Research Article
Copyright
Copyright © Materials Research Society 2000

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References

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