PHOTOCHEMICAL STUDIES OF (AMINOETHYLAMINOMETHYL)PHENETHYLTRIMETHOXYSILANE SELF-ASSEMBLED MONOLAYER FILMS

The deep UV (193 nm) photochemistry of the self-assembled monolayer fi lm PEDA, H2NCH2CH2NHCH2C6H4CH2CH2Si(OCH3)(3), has been studied on Si a nd SiO2 surfaces using UV and X-ray photoelectron spectroscopies, cont act angle goniometry, and laser-desorption Fourier transform mass spec trometry. Mechanistic studies show that Si-C cleavage is the ultimate photochemical pathway; however, interpretation of the photochemical da ta is complicated by formation of a surface-bound intermediate, as wel l as adsorption of photoproducts to the substrate surface. Treatment o f the exposed film with high ionic strength aqueous solutions is found to remove the adsorbed material. Patterned 193 nm exposure of PEDA SA M films on SiO2 produces a surface template of reactive amine groups a t relatively low doses (similar to 400 mi cm(-2)), which can be used f or selective, high-resolution attachment or deposition of materials on the unexposed regions of the film.