Role of polycrystalline titanium grain size in the formation of the concentration profiles of implanted aluminum ions

The dependence of the depth of penetration of implanted aluminum atoms into polycrystalline titanium on the grain size of initial target samples is analyzed. The irradiation was carried out by a pulse-frequency ion beam of a Diana-2 source. The increase in the modified layer thickness to 250 nm with decreasing grain size in the initial material is revealed. In the interpretation of the observed regularities, we take into account the energetically inhomogeneous composition of a beam represented by three components and probable intense sputtering of the target surface by ions. In terms of the simulation, it is found that, in samples with relatively fine grains, a significant contribution to the formation of the depth profiles of implanted atoms comes from the radiation-induced diffusion; in samples with coarse grains, it comes from the diffusion along migrating extended defects, which appear and rearrange themselves in the process of ion implantation.