Enhanced Crystalline and Magnetic Properties of Co-Doped TiO₂ Films Grown by Ultraviolet-Assisted Pulsed Laser Deposition

Using in situ ultraviolet irradiation during pulsed laser deposition (UVPLD), enhanced magnetic properties (larger remanence and coercivity) were obtained in Co-doped anatase TiO₂ films. The UVPLD grown films exhibited smaller full width at half-maximum value for the (004) peak of the Co-doped TiO₂ layer, indicating higher crystallinity. No superparamagnetic behavior was examined in the zero field cooled/field cooled measurements, suggesting an intrinsic diluted magnetic semiconductor characteristic. X-ray photoelectron spectroscopy results indicated that the cobalt in the films was in the +2 formal oxidation state and a much stronger binding coordination between oxygen and cations (Co and Ti) was inferred in the UVPLD grown films.