Two-dimensional simulations of multi-hollow VHF SiH₄/H₂ plasma

A triode multi-hollow VHF SiH₄/H₂ plasma (60 MHz) was examined at a pressure of 20 Pa by two-dimensional simulations using the fluid model. In this study, we considered the effect of the rate constant of reaction, SiH₃ + SiH₃→SiH₂ + SiH_4, on the plasma characteristics. A typical VHF plasma of a high-electron density with a low-electron temperature was obtained between two discharge electrodes. Spatial profiles of SiH₃⁺, SiH₂⁺, SiH₃^- and SiH₃ densities were similar to that of the electron density while the electron temperature had a maximum value near the two discharge electrodes. It was found that the SiH₃ radical density did not decrease rapidly near the substrate and the electron temperature was lower than 1 eV, suggesting that the triode multi-hollow plasma source can provide high quality amorphous silicon with a high deposition rate.