Oxidative scanning probe lithography has been demonstrated to be a very promising method for the fabrication of functional nanodevices.[1,2] Using self-assembly the created patterns can be used as templates for local chemical modification, introducing functionality on spatially defines spots on a substrate. In this contribution we demonstrate the combination of automation and the use of tip arrays towards the large scale surface patterning of octadecyl trichlorosilane (OTS) monolayers on silicon substrates. The electro-oxidation of OTS monolayers has been demonstrated to be a versatile robust platform for a broad range of surface modification reactions. During the oxidation process the terminal methyl groups are converted into carboxylic acids groups.[3] Subsequently the formed patterns can be used as a template in additional surface decoration steps. Additionally patterning of large areas enables the application of surface characterization techniques such as XPS or IR.
Using a tailor-made automated AFM with dedicated software and a programmable sample stage we demonstrate the automated patterning of large areas on a surface with high resolution. Although the final results depend on tip quality we have demonstrated the writing and subsequent surface functionalization of a large number (>1000) of patterns on a millimeter-sizes substrates using a single AFM-tip covering the gap from nanometer patterning to millimeter-sized applications. In addition, we will present the development and use of conductive parallel cantilever arrays. Although oxidation results depend on the applied contact force parallel passive operation of multiple cantilevers will be demonstrated. The obtainable resolution depends critically on the diameter of the used tip, lines with a width down to 10 nm by using uncoated highly doped Si-tips at higher bias voltages instead of metal coated cantilevers.
[1] D. S. Ginger, H. Zhang, C. A. Mirkin, Angew. Chem. Int. Ed. Engl. 2004, 43, 30.
[2] D. Wouters, U. S. Schubert, Angew. Chem. Int. Ed. Engl. 2004, 43, 2480.
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3] a) R. Maoz, E. Frydman, S. R. Cohen, J. Sagiv, Adv. Mat. 2000, 12, 725; b) D. Wouters, U. S. Schubert, Langmuir, 2003, 19, 9033; c) S. Hoeppener, R. Maoz, S. R. Cohen, L. Chi, H. Fuchs, J. Sagiv, Adv. Mat. 2002, 14, 1036.
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