Light-addressed sub-μm electrodes for extracellular recording and stimulation of excitable cells

An array of light-addressable sub-mum electrodes for contacting excitable cells is fabricated. These electrodes provide a free selectable cell-electrode contact with a high signal-to-noise ratio and high spatial resolution. A great number of lateral isolated sub-mum electrodes is placed on top of a photoconductor layer: hydrogenated amorphous silicon (a-Si:H). By use of a laser beam these sub-pm electrodes located under the cell can be selected forming an electrical contact via an indium tin oxide (ITO) lead to an amplifier, thus providing a high seal resistance at the cell-electrodes interface. The feasibility of light-addressing electrodes and fabrication of sub-mum electrodes on photoconductor layer is shown. (C) 2001 Elsevier Science B.V. All rights reserved.