AbstractA detailed investigation was made by ESCA of the gross structural features and chemical composition of ultrathin plasma polymer films prepared from tetrafluoropyridazine. The data reveal evidence of extensive rearrangement that accompanied polymerization and that the C:F and C:N stoichiometries of the polymer films were similar to those of the starting monomer. From an initially high contact angle with water the surfaces became completely wettable with time and this is attributed to surface hydrolysis. A comparison is made between surface and bulk compositions. Brief consideration is also given to sleeve effects.