Spinodal dewetting of thin polymer films

Abstract

Dewetting of polystyrene films on a silicon substrate is investigated as a function of film thickness h. We observe the nucleation of holes in the early stage of dewetting for relatively thick films (h>100Å), as observed previously, but the breakup of thinner films occurs through the growth of uniformly distributed surface undulations (“spinodal dewetting”). The average amplitude dh of these undulations increases exponentially up to the film rupture point where dh becomes comparable to h, as predicted by a capillary wave instability model. © 1998 The American Physical Society.