Novel Probes for Molecular Electronics

摘要

In molecular electronics, interactions between the molecules and the underlying substrate must be minimized to ensure that their electronic properties are not disturbed. Insulating films or bulk insulators are ideal substrates in this regard. However, insulating substrates require characterization tools that do not depend on conductivity. One possibility is to probe molecules on ultrathin in-rnsulating films with low-current scanning tunneling microscopy (STM) (7). Alternatively, non-contact atomic force microscopy (AFM) (2) can be used to image molecules on insulating films or bulk insulators. On page 1428 of this issue, Gross et al. (3) use an extension of the latter technique to image adatoms on thin insulating films and to probe the charge state of these adatoms. This powerful tool may find applications well beyond molecular electronics.