Tapering of nanoelectrodes for an intracellular contact via a double hard mask technique

To realize an intracellular contact between nanoelectrodes and cells, a sufficient small electrode diameter is needed [1]. A sacrificial layer process developed by the Fraunhofer IMS using deep reactive ion etching and atomic layer deposition [2] is varied. A double hard mask technique is used to taper structures in a sacrificial layer and thereby the nanoelectrodes' diameter. The principles and evaluation of the spacing technique, which allows the fabrication of sub-lithographic structures, are presented here.