In-situ X-ray diffraction investigations during high-energy oxygen ion iplantation in transition metals

An in-situ X-ray diffraction study was performed to characterize aspects of the kinetics of struc-tural phase formations in transition metals during oxygen implantation. A special designed high-temperature vacuum chamber for X-ray measurements was installed at the high-energy implantation beamline of the 3 MV-Tandetron accelerator. Titanium and molybdenum sheets were implanted with oxygen ions with an energy of 1.5 MeV up to a fluence of 1.6 × 10¹⁸ O⁺-ions/cm² without sample cooling. During implantation, the phase formation was continually investigated by in-situ and real-time X-ray diffraction (XRD) with a position sensitive proportional counter system. The phase formation was studied during annealing treatments by in-situ XRD. The obtained results were com-pared with ex-situ XRD measurements performed by different techniques at a standard diffractometer. The analysis of XRD patterns indicates the formation of a buried MoO₂ layer in molybdenum. In the Ti-samples no buried oxide is formed due to significant oxygen diffusion.