Popis: |
We have used a Ga+ focused ion beam (FIB) milling technique to produce sharp scanning‐probe microscope tips. The FIB procedure employs a roughly 0.2‐μm‐diam 20 keV Ga ion beam vector scanned in an annular pattern across the apex of an electrochemically etched wire. This method usually produces exceptionally sharp conical tips, but occasionally it generates a nearly cylindrical spike at the apex. In this paper, we show examples of the spikes, and we discuss possible mechanisms by which they are produced. |