Gd. Papasouliotis et Sv. Sotirchos, STEADY-STATE MULTIPLICITY PHENOMENA IN THE DEPOSITION OF SILICON-CARBIDE, Journal of the Electrochemical Society, 145(11), 1998, pp. 3908-3919
Citations number
28
Categorie Soggetti
Electrochemistry,"Materials Science, Coatings & Films
An experimental investigation of the occurrence of multiple steady sta
tes in the chemical vapor deposition of silicon carbide from methyltri
chlorosilane, hydrogen, and hydrogen chloride mixtures is presented in
this study. Experiments have been carried out over broad temperature,
pressure, and composition ranges in a hot-wall chemical vapor deposit
ion reactor coupled with an electronic microbalance. It has been found
that in the absence of hydrogen chloride in the feed, multiple steady
states appear at temperatures around 850 degrees C, and that the addi
tion of HCl moves the multiplicity region toward higher temperatures.
Multiple steady states have been observed over the whole temperature (
800-1400 degrees C) and pressure (20-760 Torr) region covered in our e
xperiments, with the difference in the deposition rate between the upp
er and lower stable branches exceeding in some eases two orders of mag
nitude. Since the key parameter involved in the appearance of multiple
steady states is the concentration of hydrogen chloride, which depend
s on the residence time of the reacting mixture in the reactor; the te
mperature profile, and the reactor geometry, the poor agreement among
deposition rate data reported in the literature by different groups ma
y be partly due to the multiple steady-states phenomenon. The appearan
ce of multiplicity is explained qualitatively in terms of a simplified
model of SiC deposition.