High-Temperature Au Implantation into Ni-Be and Ni-Si Alloys

Abstract

ABSTRACTThe effects of implantation temperature and target composition on the depth distribution of the implanted species were systematically investigated in the present work. Au+ ions were implanted at 300 keV into polycrystalline Ni-Be and Ni-Si alloys at temperatures between 25 and 700 °C to a dose of 1016 cm−2. The depth distributions of Au were analyzed with RBS using He+ at both 1.7 and 3.0 MeV, and those of the other alloying elements by SIMS. Theoretical modeling of compositional redistribution during implantation at elevated temperatures was also carried out with the aid of a comprehensive kinetic model. The analysis indicated that below ∼250 °C, the primary controlling processes were preferential sputtering and displacement mixing, while between 250 and 600 °C radiation-induced segregation was dominant. Above 600 °C, thermal-diffusion effects were most important. A systematic fitting of model calculations to experimental measurements provided values for various defect migration and formation parameters.