RADIATION-INDUCED REDISTRIBUTION OF IMPLANTED IMPURITIES IN AL

Ion-beam-induced migration of an implanted impurity is studied using a phenomenological model involving diffusion of the impurity, vacancies and coupling between their motion. Redistribution of implanted Mn, Fe and Ni in Al is experimentally observed using the RES technique and a nalyzed using the phenomenological model. Implantations are carried ou t at 200 keV, to a dose of 1 x 10(16) ions cm(-2) and at temperatures ranging from 77 K to 473 K. Coupled continuity equations for implanted atom and vacancy fluxes are solved to obtain theoretical fits to the experimental concentration vs. depth profiles. An effective diffusion coefficient describing radiation-induced thermal and athermal processe s is obtained from the theoretical fits and is found to have a value a few orders of magnitude higher than the normal diffusion coefficients .