(449d) Non-Lithographic Microetching of Transparent Conductive Oxides (Ito and Zno) and Semiconductors (Gaas) Based on Reaction-Diffusion Conference: AIChE Annual MeetingYear: 2006Proceeding: 2006 AIChE Annual MeetingGroup: Engineering Sciences and FundamentalsSession: Interfacial Phenomena in Conducting and Semiconducting Systems Time: Wednesday, November 15, 2006 - 4:30pm-4:55pm Authors: Smoukov, S. K., North Carolina State University Grzybowski, B. A., Northwestern University A benchtop, one-step, maskless-but-parallel method of etching micropatterns is described. Transparent conducting oxides and semiconductors are etched with lateral resolution down to 200nm using a reaction-diffusion process. Patterned hydrogel stamps act as a reservoir and a two-way "pump" transporting etchant onto the substrate while removing reaction products into its bulk. This low-cost method is suitable for rapid rototyping of bulk and thin film materials, minimizing the need for multistep lithographic processing.