Structural and magnetic properties of Mn-doped anatase TiO2 films synthesized by atomic layer deposition

Mn-doped anatase TiO2 (Mn: 1.2, 2.4 at%) thin films were grown on Si(100) via atomic layer deposition (ALD). The synthesis utilized Ti(OCH(CH3)2)4 and H2O as ALD precursors and Mn(DPM)3 as a dopant source. X-ray photoelectron spectroscopy measurements indicate that Mn is successfully doped in the TiO2 matrix and reveal information about film composition and elemental chemical states. Microstructure, crystallinity, and density were investigated with scanning electron microscopy, X-ray diffraction, and X-ray reflectivity. All ALD-synthesized films exhibited room-temperature ferromagnetism; the microstructure, density, and magnetic field-dependent magnetization of the TiO2 varied with the concentration of Mn. ALD permits precise composition and thickness control, and much higher process throughput compared to alternative techniques.