Spinodal dewetting of thin films with large interfacial slip: implications from the dispersion relation

TL;DR

This paper investigates how large interfacial slip affects the dispersion relation in spinodally dewetting thin films, revealing significant shifts in the power spectrum that impact experimental assessments of disjoining pressure.

Contribution

It demonstrates that large slip lengths cause notable shifts in the dispersion relation's maximum, affecting methods to measure disjoining pressure in thin films.

Findings

Maximum of the dispersion relation shifts to larger wavelengths with increased slip.

Predicted 20% shift in power spectrum maximum for PS films on OTS-covered Si wafers.

Large slip lengths significantly influence the interpretation of roughness spectra.

Abstract

We compare the dispersion relations for spinodally dewetting thin liquid films for increasing magnitude of interfacial slip length in the lubrication limit. While the shape of the dispersion relation, in particular the position of the maximum, are equal for no-slip up to moderate slip lengths, the position of the maximum shifts to much larger wavelengths for large slip lengths. Here, we discuss the implications of this fact for recently developed methods to assess the disjoining pressure in spinodally unstable thin films by measuring the shape of the roughness power spectrum. For PS films on OTS covered Si wafers (with slip length b approx. 1 mum) we predict a 20% shift of the position of the maximum of the power spectrum which should be detectable in experiments.