IMAGING NANOMETER-SIZE METALLIC CLUSTERS WITH THE ATOMIC-FORCE MICROSCOPE

The atomic force microscope has been used in the attractive (non-conta ct) force mode to produce images of individual nanometer-size clusters pre-formed in the gas phase and deposited on a wide variety of atomic ally-flat substrates. Using this technique, it is now possible to reli ably image pre-formed clusters in their as-deposited positions. Studie s of nanometer-size Au clusters supported on highly oriented pyrolitic graphite clearly show how the clusters are distributed across the sca nned region. Cluster coverages inferred from atomic force studies are compared to those obtained from TEM studies of amorphous carbon grids simultaneously exposed to the same cluster beam.