Structure and surface morphology of Mn-implanted TiO2

A study of structure and surface morphology together with magnetic properties of Mn-implanted rutile-type TiO2 single crystals is performed. Homogenous thin films of about 100 nm with different MnxTi1 − xO2 (x = 0.03; 0.05 and 0.07) chemical formula were obtained. The Mn ion implanted surface exhibited a dense microstructure with a nano grain size. The dependence of c/a axial ratio on manganese content suggests that Mn3+ species substituted tetragonal Ti4+. The annealing at 873 K caused changes in surface structure, morphology and roughness. A migration of manganese ions into the rutile single crystal takes place and in certain conditions Ti2O phase occurs. Mn-implanted samples exhibit room temperature ferromagnetism and a Curie temperature of 680 K. Electron spin resonance analysis evidenced that manganese is incorporated by substitution as magnetically isolated Mn4+, Mn3+ and Mn2+ species. At 0.07% contents the Mn3+ species may enter in interstitial sites contributing to extinction of substitutional magnetic moment.