Solvent assisted capillary force lithography

Capillary force lithography (CFL) utilizes the capillary-filling phenomenon of a polymeric melt into a cavity to pattern the polymer film coated on a substrate. Most CFL approaches are realized at high temperatures. The solvent-assisted CFL method proposed here realizes patterning at ambient temperature. A swollen PDMS (poly(dimethysilane)) stamp by solvent is placed in contact with a polymer thin film. As the solvent reserved in the PDMS stamp diffuses into the polymer film, the polymer can be dissolved or swollen. Then the capillary force drives the pattern formation. By carefully choosing the experimental conditions, it is possible to produce highly regular and reproducible nano- to micrometer scale polymer patterns using the same microscopic patterned mold. Complex polymer patterns can also be fabricated through the multiple printing.