Lattice site location and annealing behavior of W implanted TiO2

The implantation damage and lattice site location of W in TiO2 (rutile) was studied using the Rutherford backscattering technique in the channeling mode (RBS-C). The W ions were implanted at room temperature with fluences in the range of 10(15) to 10(17)/cm(2) into both < 1 0 0 > and < 0 0 1 > oriented single crystals. The implanted region becomes completely disordered for W doses higher than 10(16)/cm(2). After annealing experiments at temperatures up to 1100 K the results suggest that lattice recovery depends on the type of TiO2 single crystal used. While in < 0 0 1 > oriented single crystals partial epitaxial solid phase regrowth of the damaged legion is seen, for < 1 0 0 > oriented single crystals a recrystallization process occurs almost to completion. During damage recovery the high dose samples lose more than 80% of the W from the implanted region. Detailed angular scans for the main axial directions show that in the case of full recovery about 82% of the W remaining in the implanted region are incorporated on Ti lattice sites. These observations suggest that there is a strong anisotropy of the lattice recovery and diffusion properties in W implanted TiO2. (C) 1998 Elsevier Science B.V.