AN ELLIPSOMETRIC STUDY OF LB FILMS IN A CONTROLLED-ATMOSPHERE

Langmuir-Blodgett (LB) films of Cu(II) [tetrakis-(3,3-dimethyl-1-butox ycarbonyl)] phthalocyanine have already been the subject of thorough s tudy; in this case, the absorption spectrum in the UV-VIS spectral ran ge and the optical constants of the as-deposited LB film were studied. Furthermore, in order to use these LB films as optical gas sensors, e llipsometric measurements carried out on our LB films in the presence of dry air and their interaction with toluene and tetrachloroethene ar e discussed. Ln particular, reference values for thickness and complex refractive index have been determined. Moreover, the variations of th e relative thickness, the normalised refractive index and extinction c oefficient at a fixed wavelength, when these films are exposed to diff erent concentrations of toluene and tetrachloroethene, are presented. (C) 1998 Elsevier Science S.A. All rights reserved.