Characterization of Langmuir-Blodgett films of cadmium stearate by penning ionization electron spectroscopy

Abstract

The characterization of cadmium stearate films prepared on silicon substrates by the conventional Langmuir-Blodgett method (for 1 layer) and those by the horizontal lifting (HL) method (for 2–4 layers) was carried out by means of Penning ionization electron spectroscopy and UV photoelectron spectroscopy. The analysis of the relative band intensities of the Penning spectrum indicates that the hydrocarbon end of the stearate ion is exposed outside the surface for all the films studied. The combination of this result and those of an X-ray diffraction study suggests that the films prepared by the HL method have a Y-type structure. The structural changes in the film due to increases in film thickness and to thermal annealing were also studied by Penning ionization and photoelectron spectroscopies.