Integrating an ultramicroelectrode in an AFM cantilever: Combined technology for enhanced information

We present a novel approach to develop and process a microelectrode integra ted in a standard AFM. tip. The presented fabrication process allows the in tegration of an electroactive area at an exactly defined distance above of the end of a scanning probe tip and the subsequent remodeling and sharpenin g of the original AFM tip using a focused ion beam; (FIB) technique (See re f 1 for patent information). Thus, the functionality of scanning electroche mical microscopy (SECM) can be integrated into any standard atomic force mi croscope (AFM). With the demonstrated approach, a precisely defined and con stant distance between the microelectrode and the sample surface can be obt ained, alternatively to the indirect determination of this distance usually applied in SECM experiments, Hence, a complete separation of the topograph ical information and the electrochemical signal is possible. The presented technique is a significant step toward electrochemical imaging with submicr ometer electrodes as demonstrated by the development of the first integrate d frame submicroelectrode.