SCANNING-TUNNELING-MICROSCOPY AND SPECTROSCOPY WITH FULLERENE COATED TIPS

We report a marked improvement in STM images of graphite surfaces take n in air when scanning is performed with tunneling tips which have bee n previously exposed to thin films of fullerenes. Spectroscopy, TEM me asurements, and previous studies on the bonding of C60 to various subs trates indicate that such treatment results in the adsorption of fulle rene molecules on the tip. The adsorbed fullerene molecules stay attac hed to the tip, and once prepared are stable with respect to sample tr ansfer. The reduced noise and enhanced corrugation of the images of gr aphite surfaces obtained with these fullerene-coated tips suggest that a modified Pethica mechanism may play an important role in obtaining these images.