AFM Studies of Confined Dewetting On Gradient Patterned Surfaces

Published

August 1, 2000

Author(s)

Alamgir Karim, A Sehgal, Eric J. Amis

Abstract

Spinodal dewetting of ultra thin films driven by thermal fluctuations is considered analogous to phase separation accompanied by composition fluctuations. Such dynamic processes are extremely sensitive to perturbation by external fields. In this study dewetting of thin polymer films on a self-assembled monolayer (SAM) pattern of chemical functionality is investigated. The SAM patterns are created by the stamping technique to give a step gradient in the period of bands of methyl and carboxyl terminated alkyl chains tethered to the substrate. AFM is used to study the change in droplet dimensions, the size distribution, and their spatial ordering. The temporal evolution of the dewetting in the early stages is also monitored. Both the early stage spinodal breakup as well as the late stage droplet array reflect the symmetry of the underlying SAM pattern showing sensitivity of the process to variations of substrate surface energy. Decreasing the bandwidth of the striped pattern in a regular fashion across the substrate results in a complete snapshot ranging from multiple droplets per band, to their coalescence, confinement, and disorder with narrowing bandwidths. The control of this spontaneous random phenomenon may be used to create surface topologies that can serve as polymeric platforms for nanoscale templated applications

Proceedings Title

American Chemical Society National; Division of Polymer Chemistry, Meeting | | | American Chemical Society (ACS)

Volume

41

Issue

No. 2

Conference Dates

August 20-24, 2000

Conference Location

Undefined

Conference Title

Polymer Preprints

Pub Type

Conferences

Download Paper

Local Download

Keywords

combinatorial, polymer thin films, SAM Patterns, spinodal dewetting

Citation

Karim, A. , Sehgal, A. and Amis, E. (2000), AFM Studies of Confined Dewetting On Gradient Patterned Surfaces, American Chemical Society National; Division of Polymer Chemistry, Meeting | | | American Chemical Society (ACS), Undefined, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=851744 (Accessed December 26, 2024)