NANOMETER-SCALE SYNTHESIS AND ATOMIC-SCALE MODIFICATION WITH THE SCANNING TUNNELING MICROSCOPE

The structure or composition of a surface may be locally altered in either of two fundamental ways using the scanning tunneling microscope (STM). A modification of the surface may be induced resulting in the rearrangement and/or removal of surface atoms, or in the transfer of atoms from the tip to the sample surface. In many recent experiments, the modification of surfaces has involved a single atom or an ensemble of a few atoms. Alternatively, the localized synthesis of a new material from reactants external to the STM tip and sample can be induced using at least three experimental strategies. A typical distance scale involved in such experiments is 10 nm (i.e., the smallest lateral dimension of the material synthesized). Progress in the areas of localized modification and localized syntheses with the STM (with greater emphasis on the latter) is summarized in this review.