M. Dekeijser et Gjm. Dormans, MODELING OF ORGANOMETALLIC CHEMICAL-VAPOR-DEPOSITION OF LEAD TITANATE, Journal of crystal growth, 149(3-4), 1995, pp. 215-228
The growth of lead titanate by organometallic chemical vapour depositi
on using the precursors tetraethyllead, tetraisopropoxidetitanium and
oxygen, is modelled. An initial partial decomposition of the precursor
s is postulated to take place in the gas phase. These partial decompos
ed species then diffuse to the surface followed by a dissociative adso
rption. The Pb and Ti adsorbates make use of the same sort of adsorpti
on site thereby introducing a competitive adsorption mechanism. In a n
ext step the adsorbates decompose further and react with adsorbed oxyg
en, leading to the formation of intermediate compounds of lead oxide,
and titanium dioxide. These individual oxides then either react to for
m the lead titanate or are incorporated in the film as such. Desorptio
n of the intermediate lead oxide compound is included in the model. Th
e model may be used to describe the dependence of the growth rate and
the composition of the layer as a function of the deposition temperatu
re, precursor and oxygen partial pressures. A reasonable agreement bet
ween the model predictions and experimental results is obtained.