Numerical simulation on silane plasma chemistry in pulsed plasma process to prepare a-Si :H thin films

Dong Joo Kim, Jin Yi Kang, Anna Nasonova, Kyo Seon Kim, Sang June Choi

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7 Citations (Scopus)

Abstract

We numerically calculated the effects of pulse modulation (plasma-on and -off times) on the concentration changes of the chemical species (SiH 4, SiHx, SiHx + and polymerized negative ions) and also the growth rate of a-Si : H thin films in the pulsed SiH4 plasmas. During the plasma-on, SiHx is generated quickly by a fast dissociative reaction of SiH4, but, during plasma-off, SiHx disappears rapidly by a reaction with hydrogen and also by the deposition onto the reactor wall. During the plasma-on, the negative ions are polymerized by the reactions with SiH4, but, during the plasma-off, they disappear by neutralization reactions with positive ions. As the plasma-on time increases or as the plasma-off time decreases, the time-averaged concentrations of SiHx and negative ions and also the time-averaged film growth rate increase. This study shows quantitatively that polymerized negative ions, which are not considered to be preferred precursors for the high-quality thin films, can be efficiently reduced by the pulsed plasma process.

Original languageEnglish
Pages (from-to)154-164
Number of pages11
JournalKorean Journal of Chemical Engineering
Volume24
Issue number1
DOIs
Publication statusPublished - 2007 Jan 1

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Keywords

  • Highquality thin film
  • Polymerization of negative ions
  • Pulse modulation
  • Pulsed plasmas
  • SiH plasma chemical reactions

ASJC Scopus subject areas

  • Chemistry(all)
  • Chemical Engineering(all)

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