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

An in situ X-ray diffraction study was performed to characterize aspects of the kinetics of structural phase formations in transition metals during oxygen implantation. A specially designed high-temperature vacuum chamber for X-ray measurements was installed at the high-energy implantation beamline of the 3MV-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 x 10(18) o(+)- ions/cm(2) 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 process by in situ XRD. The obtained results were compared 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. (C) 2004 Elsevier Ltd. All rights reserved.