How disjoining pressure drives the dewetting of a polymer film on a silicon surface

We have used optical microscopy, atomic force microscopy, and ellipsometry to study the dewetting of films of a perfluoropolyether polymer on silicon substrates. The disjoining pressure of these films is determined, for the f irst time for a dewetting system, by using noncontact atomic force microsco py to measure the dimensions of the liquid dewetting droplets. The determin ed disjoining pressure explains the different dewetting processes observed for different initial film thicknesses and is dominated by structural fords and by the inability of the polymer to spread on its own monolayer.