Taking nanolithography beyond semiconductors

A new technique of chemical patterning developed at Penn State combines conventional lithography with molecular self-assembly for the creation of multifunctional surfaces. In this technique, a robust lithographic resist is patterned to protect chemical functionality in selected areas. In unprotected areas, the chemical functionality is selectively removed so that other chemical functionality can be placed in these regions. The process can be repeated to create multifunctional surfaces. (top left) A lateral-force microscopy (LFM) image contrasting COOH-terminated regions of high friction (light) with CH3-terminated regions (dark). (top right) Field-emission scanning-electron microscope (FESEM) image contrasting the COOH-terminated regions (dark) and CH3-terminated regions (light) (bottom) 3D rendered Field-emission scanning-electron microscope (FESEM) image of a surface patterned with two chemical functionalities. Credit: Penn State