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

The formation of self-assembled monolayers of octadecylsiloxane adsorbed fr om dilute solutions of octadecyltrichlorosilane in toluene onto freshly cle aved mica surfaces was investigated using atomic force microscopy (AFM) in tapping mode as a well-suited tool to obtain local information on the adsor ption process. Three different measurement methods have been used: ex situ measurements and in situ measurements under stopped flow/deposition as well as continuous flow/deposition conditions. Although valuable information on the growth process can be obtained under stable and reproducible condition s with all methods addressed, in situ measurements bear a number of signifi cant advantages for the investigation of such dynamic processes. (C) 1999 E lsevier Science B.V. All rights reserved.