The in-diffusion of Pt into a low-doped n-type float zone Si guided and enhanced by radiation damage produced by co-implantation of He ions was investigated. The implantation of 1MeV Pt ions at different doses ranging from 5 x 1011 to 5 x 1012/cm2 was used to produce a finite source for Pt diffusion. Single and multiple energy implantation of He ions with energies 7, 9, 11 and 13MeV introducing different profiles of radiation defects were applied to enhance and shape the diffusion of Pt atoms performed by 1200s annealing at 725C in vacuum. The distribution of in-diffused Pt was studied by monitoring the acceptor level of substitutional Pt, Pts-/0 (EC−ET = 0.23eV) by deep level transient spectroscopy. Results showed that the He co-implantation significantly enhances Pt diffusion and allows its control up to the depths of hundreds of μm. The resulting Pts distribution was given by the profile of radiation damage produced by He ions while the amount of in-diffused Pts could be controlled by the dose of Pt implantation. It was also shown that an extra annealing at 685C performed prior to He implantation substantially increased the amount of in-diffused Pt. Radiation Enhanced Diffusion of Implanted Platinum in Silicon Guided by Helium Coimplantation for Arbitrary Control of Platinum Profile. P.Hazdra, J.Vobecký: Nuclear Instruments and Methods in Physics Research Section B, 2005, 230[1-4], 225-9