Radiation-stimulated surface diffusion of adatoms on a tungsten {321} face
The surface erosion of tungsten bombarded with accelerated 5-keV helium atoms has been studied by the method of field-ion microscopy. Radiation-stimulated appearance of adatoms localized in the central region of terraces on the {321} W face has been observed. The distribution of W adatoms on {321} terraces is characterized by the presence of zones free of adatoms in the vicinity of atomic steps. The existence of “empty” zones upon irradiation is evidence of transient surface diffusion. The diffusion path lengths of adatoms on the {321} W face reach six interatomic distances and reveal anisotropy of the radiation-stimulated transient surface diffusion.