Study on the Electron Transport in SiH₄/Ar Mixtures using Monte Carlo Simulation

Abstract

A Monte Carlo technique is used to investigate the electron transport and to compile data on the transportparameters in SiH₄/Ar mixtures under a wide range of the electric field from E/p₀=20 to 1000 V/cmTorr andSiH₄ mixing ratios from 0 to 100%. The calculations show that the drift velocity v_d, the diffusion coefficientp₀D_L, and the electron mean energy εdecrease monotonously with increasing the silane content, except thecase in a low electric field. On the other hand, the ionization rate Ris, the attachment rate R_at, the vibrational excitation rate R_vb13 and R_vb24 and the dissosiation rates R_d2, and R_d3, of the silane molecule have a maximumvalue at a certain mixing ratio. The ionization rate R_ia and the excitation rate R_ext(1-6) of argon atom, however, decrease sharply with increasing the silane content. These results are discussed using the data on thevariations of the electron energy distribution due to the electric field strength and the mixing ratios.