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Redox current amplification has been demonstrated using carbon interdigitated array ͑IDA͒ nanoelectrodes derived from precursor polymer microstructures through conventional photolithography and pyrolysis. This simple conversion process, also known as carbon-microelectromechanical systems, enables nanometer-level fabrication of carbon materials in a reproducible and an economic manner. We demonstrated that with carbon IDA nanoelectrodes fabricated in two mask processes a current amplification factor of 25 can be obtained. This high amplification factor is a result of the efficient recycling of redox species between the 1:1 aspect ratio carbon nanoelectrodes. This type of a current amplification value is hard to obtain when using more traditional flat nanometer level spaced noble metal IDA electrodes fabricated with more expensive nanopatterning processes such as E-beam lithography.

The study of the biocompatible properties of carbon microelectromechanical systems (carbon-MEMS) shows that this new microfabrication technique is a promising approach to create novel platforms for the study of cell physiology. Four different types of substrates were tested, namely, carbon-MEMS on silicon and quartz wafers, indium tin oxide (ITO) coated glass and oxygen-plasma-treated carbon thin films. Two cell lines, murine dermal fibroblasts and neuroblastoma spinal cord hybrid cells (NSC-34) were plated onto the substrates. Both cell lines showed preferential adhesion to the selectively plasma-treated regions in carbon films. Atomic force microscopy and Fourier transform infrared spectroscopy analyses demonstrated that the oxygen-plasma treatment modifies the physical and chemical properties of carbon, thereby enhancing the adsorption of extracellular matrix-forming proteins on its surface. This accounts for the differential adhesion of cells on the plasma-treated areas. As compared to the methods reported to date, this technique achieves alignment of the cells on the carbon electrodes without relying on direct patterning of surface molecules. The results will be used in the future design of novel biochemical sensors, drug screening systems and basic cell physiology research devices.

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We demonstrate a novel method to fabricate arrays of resorcinolformaldehyde xerogel (RFX) based high aspect ratio (HAR) threedimensional (3-D) hierarchical C-MEMS structures. Starting from a master pattern of HAR 3-D posts fabricated in SU-8 negative photoresist by photolithography, a negative PDMS stamp with arrays of holes was prepared by micromolding. The PDMS stamp was then used to fabricate HAR 3-D RFX posts by replica molding. The 3-D RFX posts thus fabricated were electrosprayed with SU-8 or an RF sol in the form of submicron or nano sized droplets and followed by pyrolysis to yield HAR 3-D hierarchical carbon posts. To characterize their use in C-MEMS based batteries, galvanostatic (charge and discharge) experiments on RFX derived carbon showed that it can be reversibly intercalated with Li ions and possesses superior intercalation properties as compared to SU-8 derived carbon which is a widely used material in C-MEMS. 10.1149/06107.0045ecst ©The Electrochemical Society ECS Transactions, 61 (7) 45-54 (2014) 45 ) unless CC License in place (see abstract). ecsdl.org/site/terms_use address. Redistribution subject to ECS terms of use (see 218.248.6.153 Downloaded on 2015-03-17 to IP