In situ and ex situ AFM investigation of the formation of octadecylsiloxane monolayers

The formation of self-assembled monolayers of octadecylsiloxane adsorbed from dilute solutions of octadecyltrichlorosi- lane in toluene onto freshly cleaved mica surfaces was investigated using atomic force microscopy AFM.in tapping mode as a well-suited tool to obtain local information on the adsorption process. Three different measurement methods have been used: ex situ measurements and in situ measurements under stopped flowrdeposition as well as continuous flowrdeposition conditions. Although valuable information on the growth process can be obtained under stable and reproducible conditions with all methods addressed, in situ measurements bear a number of significant advantages for the investigation of such dynamic processes. q1999 Elsevier Science B.V. All rights reserved.