Toward Single Atom Chemical Analysis with STM

Abstract

An important function of microscopy is the chemical analysis of the sample. Chemical analysis with an atomic resolution microscope can mean two different things. First, for a sample of known composition or adsorbed species, it means distinguishing the chemical species from the atomic image. Second, for a sample of unknown composition, it means the identification of the chemical components from the atomic resolution image. Here I compare available methods of chemical identification in field ion microscopy (FIM) and scanning tunneling microscopy (STM), and report our progress in achieving true atomic resolution for a non-destructive chemical analysis of a sample surface using STM.