Influence of substrate surface on Langmuir-Blodgett multilayers

The stacking structure of cadmium stearate Langmuir-Blodgett films as a function of the wettability and coarseness of the substrate surface as controlled by chemical and physical treatments was examined by reflection X-ray diffraction for the purpose of obtaining high quality deposited samples. It is seen that for intermediate surface wettabilities the stacking order tends to be worse than for more hydrophilic or hydrophobic surface states. It is seen that the rather corrosive surface treatments hinder the regular piling up of the monolayers even when the wettability of the substrate surface is suitable. Although these results lead to the somewhat natural conclusion that the surface of a substrate should be smooth and sufficiently hydrophilic or hydrophobic, it is suggestive for further investigations of the influence of the surface state on the order of stacking.