title: Stability of thin wetting films on chemically nanostructured surfaces.
abstract: The morphology and stability of thin volatile wetting films on model chemically patterned surfaces composed of periodic arrays of alternating completely and partially wettable nanostripes are investigated. The equilibrium film morphology is recorded as a function of undersaturation using noncontact atomic force microscopy. Films spanning the entire pattern are found to be stable only for thicknesses in excess of a critical value, h(c), whereas thinner films spontaneously dewet the partially wettable regions of the substrate. The critical thickness h(c) increases linearly with the width of the partially wettable stripes in good agreement with an interface displacement model derived from microscopic density functional theory. These results provide detailed insights into the dewetting of thin films driven by competing intermolecular forces.
authors.affiliation: Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, New York 11973, USA. checco@bnl.gov
authors.forename: A
authors.initials: A
authors.lastname: Checco
authors.forename: B M
authors.initials: BM
authors.lastname: Ocko
authors.forename: M
authors.initials: M
authors.lastname: Tasinkevych
authors.forename: S
authors.initials: S
authors.lastname: Dietrich