Formation and evaluation of self-assembled monolayers derived from conjugated silylthiophene derivatives

We synthesized soluble rod-like silylthiophene, silylbithiophene, and silylquaterthiophene derivatives with various functional groups. Their self-assembled monolayer films on silicon oxide were evaluated by atomic force microscopy, X-ray photoelectron spectroscopy, water contact angle measurements, and fourier transform infrared-reflection absorption spec- troscopy. We found that the molecular density moleculesrarea.of the resultant films increased with thiophene moiety. This is probably due to the effective p-stacking of aromatic rings between molecules. q1999 Elsevier Science B.V. All rights reserved.