SAND IN THE LABORATORY. PRODUCTION AND INTERROGATION OF GAS PHASE SILICATES.

Abstract

Given its technological importance, the literature abounds with models for plasma enhanced chemical vapor deposition of the SiH$_4$/O$_2$/Ar system. In a continuing effort to identify and characterize the optical spectra of Si$_3$ generated in a SiH$_4$/Ar pulsed discharge sourcefootnote{The electronic spectrum of Si$_3$ I: the triplet D$_{3h}$ system� Reilly, N. J.; Kokkin, D. L.; Zhuang, X.; Gupta, V.; Nagarajan, R.; Fortenberry, R. C.; Maier, J. P.; Steimle, T. C.; Stanton, J. F.; McCarthy, M. C., J. Chem. Phys. 136(19), 194307, 2012.}, we detected, via two dimensional (2D) LIF, a relatively strong electronic transition in the 570-600,nm region that is strongly enhanced by the addition of a small amount of O$_2$. The excitation spectrum shows resolved band structure at the pulsed laser resolution of 0.5,cm$^{-1}$ and exhibits a radiative lifetime of 1.97,$mu$s. The dispersed fluorescence exhibits three vibrational progressions and an unusually small splitting of approximately 50,cm$^{-1}$. Here we report on efforts to identify the molecular carrier of these bands, with particular interest paid to species resulting from oxygen impurities in the silane discharge.