Contour Offset Algorithm (COA) in nano Replication Printing (nRP) for fabricating nano-precision features

Abstract

A Contour Offset Algorithm (COA) has been developed to fabricate nano-precision figures or patterns in the range of several microns by a nano-Replication Printing (nRP) process. In the nRP process, a ferntosecond laser illuminated on photosensitive monomer resin to induce polymerization of the liquid monomer according to a volume pixel (voxel) matrix which is transformed from a two-tone (black and white) bitmap file. After two-photon absorbed photo-polymerization (TPP), a droplet of ethanol is dropt on a glass plate to remove the unnecessary remaining liquid resin, leaving only polymerized patterns on the glass plate. In the nRP process, the replicated patterns do not precisely coincide with the initial designs due to an essential shortage of nRP process. Fabricated patterns by means of the nRP process become larger than the design in the amount of the voxel radius. In this work, an outer contour matrix of an initial design was constructed and reduced according to an offset-ratio calculated by the COA in order to obtain more precise patterns. Both the effectiveness and the accuracy of the proposed algorithm were demonstrated through chosen example.