Micromachined SPM probes with sub-100 nm features at tip apex

Abstract

We have developed a fabrication process that allows thin films to be patterned at the end of a sharp tip. Using this method, many different material contrasts can be achieved on the apex of a scanning probe microscope tip. For example, small apertures down to 30 nm have been patterned into an aluminium film covering quartz tips to form scanning near-field optical microscopy probes. Also, small well-defined metal electrodes can be fabricated on the tip apex, which can be used for electrochemical measurements. The tip structuring process is a batch fabrication method and is based on CMOS-compatible technologies, which means that it can be integrated easily into an existing microfabrication process. Furthermore, it allows the patterning of a wide range of tip heights, materials or geometries. Copyright © 1999 John Wiley & Sons Ltd.