Scanning Microscopy


The field ion microscope, with its ability to depict individual metal atoms on crystals, has made it possible to measure diffusivities of individual atoms. After a brief sketch of the technical problems in such quantitative studies of surface diffusion, data on the effects of different surface structures upon the diffusion characteristics of individual a toms are presented for both bee and fee metals. Through the use of the field ion microscope the mechanisms of atomic motion have for the first time become accessible to direct examination; recent studies are presented which indicate that the traditional view of surface diffusion as a random walk of adatoms between adjacent sites on the surface is not generally applicable. The field ion microscope has also revealed the importance of clusters as possible contributors in surface transport, and work aimed at defining the atomic steps important in cluster mobility is therefore briefly reviewed.

Included in

Biology Commons