Sequential and parallel patterning by local chemical nanolithography

Abstract

Nanometre-size menisci of various liquids such as water, ethanol, 2-propanol, octane, and 1-octene have been formed and used to confine chemical reactions by using an atomic force microscope. The application of a bias voltage between a conductive scanning probe tip separated a few nanometres from a sample surface enables the field-induced formation of a nanometre-size liquid meniscus. Those menisci are subsequently used to fabricate nanometre-size structures on different materials. The growth kinetics of the fabricated nanostructures depends on the chemical nature of the liquid. Higher growth rates are obtained with octane. The differences in growth rates underline differences in the chemical composition of the fabricated motifs. We report the fabrication of different nanostructures such as arrays of dots, wires and stripes. The fabricated motifs can be used as templates for the growth of conjugated molecular materials. We also show that the local chemical processes can be scaled up for parallel patterning. Patterning arrays of parallel lines 100 nm apart has been demonstrated over mm2 regions.