High resolution electron energy loss spectroscopy study of polymer-metal interfaces

Polyimide and polyaniline films are used in a wide range of electronic applications ranging from sensors and displays to integrated circuits. In many of these applications, interfaces between polymers and other materials play an important role in determining device performance. In this work, the vibrational and electronic structure of interfaces formed between metals and vapor-deposited polyimide and polyaniline films was examined using high resolution electron energy loss spectroscopy (HREELS). A state-of-the-art spectrometer was employed in these studies which enabled the organic films to be characterized in unprecedented detail. The results of this investigation demonstrate that interface formation is highly sensitive to specific interactions between polymers and metal substrates. Identifying these interactions was facilitated by probing the adsorption and reaction of individual monomers on metal surfaces. The effect of polymer-substrate interactions was most evident by differences in the chemical and electrical properties between vapor-deposited polyaniline films $\u3c$100 and $\u3e$1000 Angstroms thick. Finally, a comparison of vapor-deposited and solution-cast films revealed that processing conditions can strongly influence polymer morphology and homogeneity. HREELS data indicates that vapor deposition may be a viable alternative to wet-chemical fabrication techniques for incorporating polyimides and polyanilines into a variety of polymer thin film applications