Experiments were performed which were aimed at understanding 3 different phenomena which deformed solid surfaces during bombardment with 24MeV heavy ions. These phenomena were density changes, anisotropic growth (thinning of the solid along the normal to the surface and growth in the surface plane without density change) and lateral mass transport. The latter occurred only if the ion beam was not perpendicular to the surface. It involved the displacement of some of the implanted material along the surface in the direction of the component of the ion velocity which was parallel to the surface. It resulted in the creation of a ditch and a dike at opposite edges of the bombarded zone. The contribution of lateral mass transport to the surface deformation was deduced, as a function of fluence, flux, and species, for various projectiles and materials. Auger analysis of the surface eliminated sputtering and surface diffusion as being other possible causes of the ditch and dike structure.

Directional Effects during Ion Implantation: Lateral Mass Transport and Anisotropic Growth M.Chicoine, S.Roorda, L.Cliche, R.A.Masut: Physical Review B, 1997, 56[3], 1551-60