Capillarity-induced patterning of thin polymer films and related regular dewetting structures

Abstract

When a thin polymer film is spin-coated oil a solid Substrate and heated above its glass transition temperature (T-g) while in conformal contact with a patterned polydimethytsiloxane (PDMS) mold, capillarity forces the polymer melt to fill up the void space of the mold, thereby forming a negative replica of the polymer after mold removal. In this Study, particular emphasis is given to the nodal dewetting phenomenon in a thin, laterally confined polymer film that sticks to a substrate. When heated above the glass transition temperature, the film dewets from the Substrate through the generation of nodal waves, with the PDMS wall acting as a node. Various superposed waves were observed depending oil the intrinsic period of dewetting and the confining width of the cavity.