Ellipsometry and x-ray reflectometry characterization of self-assembly process of polystyrenesulfonate and polyallylamine

Self-assembly of polyelectrolytes-polystyrenesulfonate (PSS) and polyallylamine (PAH) with added salts of MnCl and NaBr was studied by x-ray reflectometry and ellipsometry technique. The thickness of PSS-PAH bilayer was measured to be 5.1±0.2 nm according to reflectometry and 6.1±0.7 nm according to ellipsometry. The discrepancy in data is attributed to the difference in the interaction of the interfaces with x-rays and visible light. The films are found to be rather homogeneous and the deposition process regular. The refraction indices of the deposited films were found to ben0=1.50±0.05,k0=0.07±0.05,ne=1.53±0.05ke=0, optical axis being perpendicular to the surface. The values of refractivity characterize the whole film (up to seven bilayers) and do not vary with increasing thickness.