CR METALLIZATION OF POLYPHENYLACETYLENE THIN-FILM INVESTIGATED BY XPS

The early stages of Cr/polyphenylacetylene (PPA) interface formation h ave been investigated by means of X-ray photoemission spectroscopy (XP S). The core level C 1s and Cr 2p3/2 spectra of the substrate and of t he metal respectively, recorded at a constant metal evaporation rate, suggest the formation of a charge-transfer complex involving the pi-co njugated chain carbons mainly, while a weak interaction with the aroma tic carbons of the phenyl group occurs at initial Cr coverages (0.5-3 angstrom). The growth-mode of Cr on PPA seems to proceed at first by m etal monolayer deposition followed by cluster formation.