CHARACTERIZATION OF ADSORPTION IN FLOW-TYPE ATOMIC LAYER EPITAXY REACTOR

Numerical model calculations describing the propagation of an adsorpti on wave in a low-pressure channel-type ALE reactor are carried out. Th e effect of channel parameters and flow rate of the carrier gas as wel l as diffusion and sticking coefficients of the precursor on the propa gation of the adsorption wave are studied. It is shown that the surfac e density of adsorption sites and the diffusion coefficient of the pre cursor molecules can be determined from the precursor pulse delay time measurements. Using the time dependence of the precursor concentratio n or that of the surface coverage, both measured at the channel outlet , the sticking coefficient of the precursor can be calculated.