[en] Radioactive ³¹Si was used as a tracer to study silicon self-diffusion in thin film silicides of cobalt, nickel, palladium and platinum. The specimens were prepared by sequential electron beam evaporation of radioactive ³¹Si and of the metal onto cleaned silicon wafers. By vacuum annealing at the appropriate formation temperature a silicide about 250 nm thick containing a sharp radioactive band about 50 nm thick was generally formed. Subsequent heating above the formation temperature resulted in a spreading of the activity owing to silicon self-diffusion. Activity profiles in the silicides were measured by a combination of ion beam sputtering, radioactivity counting and Rutherford backscattering of charged nuclear particles. (orig.)