The polarizabilities and activation energies for the surface diffusion of adatoms were determined by using field-ion microscopic techniques. The polarizability and activation energy were deduced from an investigation of adatom surface diffusion on a Mo tip, with and without an applied electric field, respectively. The applied electric field imposed a driving force on the adatoms and, by measuring the migration velocity of directional walks of the adatoms, the polarizabilities could be obtained. The activation energies were determined by measuring the displacements of adatoms on the tip surface, at various temperatures, using random walk theory. The values which were obtained for the activation energies were 0.25, 0.30, and 0.50eV for Ga, In, and Sn, respectively. The values of the polarizabilities were lower than those for free atoms.

A.R.Saadat: Journal of Physics D, 1994, 27[2], 356-9