Preliminary experimental data on the chemical composition and properties of films 1200-2000 Å thick from representative monomers of silanes, siloxanes and silazane are presented. Fourier transform IR spectroscopy, electron spectroscopy for chemical analysis (ESCA) and contact angle measurements were used to characterize the films as deposited at ambient temperature and after thermal treatment up to 300 °C. For an evaluation of the film integrity the relative pinhole density was determined using an electrolytic bubble trail technique. For the as-deposited films the elemental ratios derived from the ESCA study are similar to those calculated for the corresponding monomers. These analyses show that the post-deposition thermal annealing causes a significant change in the surface and bulk composition and consistently provides defect-free films. © 1983.