ABSTRACT
A general method has been developed for transferring interfacially trapped, submonolayer hexagonal arrays of silica particles for nano- and mesoscopic surface patterning. Poly(n-butyl acrylate) and poly(n-butyl acrylate-random-N,N-diethylaminoethyl acrylate) brushes were grafted on the substrates via the "graft-from" method using atom transfer radical polymerization. The polymer brush served as an adhesive promoter between the particles and the substrate and proved to be effective for locking the particles in the hexagonal lattice against the lateral capillary force arising from a thin layer of water attached to the surface of the substrate. Several parameters that influence preservation of the order of the particle arrays were examined. These include brush thickness, brush composition, interparticle distance, and particle diameter.
ABSTRACT
A colloidal lithography method has been developed for patterning nonplanar surfaces. Hexagonal noncontiguously packed (HNCP) colloidal particles 127 nm-2.7 µm in diameter were first formed at the air-water interface and then adsorbed onto a substrate coated with a layer of polymer adhesive â¼17 nm thick. The adhesive layer plays the critical role of securing the order of the particles against the destructive lateral capillary force generated by a thin film of water after the initial transfer of the particles from the air-water interface. The soft lithography method is robust and very simple to carry out. It is applicable to a variety of surface curvatures and for both inorganic and organic colloidal particles.
