SURFACE CHARACTERIZATION OF PULSED UV-LASER MODIFIED POLYAMIDE FILMS

Thin film samples of Kapton HF polyamide have been modified by UV-radi ation using a pulsed excimer laser with per pulse fluence ranging from 29-50 mJ/cm(2). The resulting samples have been characterized using S canning Tunneling Microscopy, Atomic Force Microscopy. FTIR ATR spectr oscopy and Surface Enhanced Raman Spectroscopy. Topographical results indicate that, as per pule fluence increases, surface melting, vaporiz ation and eventually surface ablation occur. Raman results indicate th e formation of graphitic carbon at the surface of the film. For highly modified samples the graphitic carbon exists in regions which exhibit localized structure on the nanometer scale. For these samples, only g raphitic carbon is present at the surface of the film. For samples whi ch involve a lesser degree of modification, both polyamide and carbon are present at the surface of the film, FTIR ATR results are consisten t with a loss of crystallinity and an introduction of new conformation al states in the bulk of the polyamide film due to subsurface heating. (C) 1997 Elsevier Science S.A.