Characterization and aluminum metallization of a parylene AF-4 surface

Abstract The surface of vapor deposited parylene AF-4 [poly( α , α , α ′, α ′-tetrafluoro- p -xylylene)] was characterized by atomic force microscopy (AFM) and X-ray photoelectron spectroscopy (XPS). Subsequent interactions with trimethylaluminum (TMA) were studied by XPS. TMA was adsorbed onto an unmodified parylene AF-4 sample (30 L, 112 K). The sample was then annealed to 300, 550 and 600 K (sequentially) in ultra-high vacuum. A reaction occurs between the precursor, the polymer surface and physisorbed water at or below 300 K, producing Al–C, Al–O and Al–F bonds as evidenced by changes in the XPS spectra. The reaction produces a thermally stable, aluminum-oxide film bound to the polymer through aluminum–carbon bonds. A fluorine concentration gradient exists in the form of a fluorinated aluminum oxide across the film, with increasing fluorination toward the adlayer/polymer interface.