Modification of parylene AF-4 surfaces using activated water vapor

In this study, we investigate the addition of oxygen functionalities to par ylene AF-4 using X-ray photoelectron spectroscopy (XPS). Subsequent reactio ns with trimethylaluminum (TMA) were also studied by XPS. Samples were expo sed to water vapor that was passed over a heated W filament, and comparison is made with similarly exposed polystyrene. Oxygen incorporation occurred in both polymers and was substantially greater in polystyrene. Defluorinati on occurred in the parylene sample, and X-ray photoelectron spectra indicat e that the oxygen is chemically bound to the polymer surface. TMA was dosed at room temperature onto the parylene samples, and prior modification of t he AF-4 surface resulted in enhanced reactivity toward TMA. Atomic force mi croscopy (AFM) is used to characterize the surfaces and demonstrates that n o significant surface roughness occurred due to the modification process. ( C) 1999 Elsevier Science B.V. All rights reserved.