Three-Dimensional Silicon-based MEA with High Spatial Resolution

A new approach based on three-dimensional tip electrodes has been developed as a way to increase the electrical oupling between the neural cells and the individual sensors in a microelectrode array (MEA). With respect to standard planar electrodes, the electrical coupling between an electrode and a neural cell is improved as benefit of an increased cell-electrode contact area. Thus using a custom fab-rication process, three-dimensional MEAs exhibiting a higher spatial resolution than classical inte-grated MEA systems have been manufactured on a silicon wafer. These MEAs have an electrode di-ameter of 3-4 um, a height of 1.75 um, and a pitch dimension of 5-6 um. In-vitro electrical measure-ments and electrophysiological experiments using standard planar electrodes as well as the proposed three-dimension electrodes are currently performed.