The Fraunhofer IMS has recently developed a technique for producing nanoelectrodes that are generated by atomic layer deposition (ALD) in a via deep reactive ion etching (DRIE) structured sacrificial layer. This method enables the fabrication of CMOS- and biocompatible nanoelectrodes with suitable ALD-materials. Improvements of the established fabrication processes and the electrochemical characterization of such electrodes are presented. In the frame of the Fraunhofer-Max-Planckcooperation project ZellMOS different types of nanoelectrodes are studied. Their diameter is in the range of 200 nm and thereby sufficiently small to be taken up by living cells. In addition, the electrodes are mechanically enforced by an oxide layer at the nanoelectrodes’ bottom.