Sol-gel thin films of BaFe12O19 from chemically modified alkoxide precursors

Homogeneous BaFe12O19 (BaM) thin films have been prepared by the dip-coating technique on microscope slides and SiO2 wafers using barium and iron alkoxides as precursors, and diethanolamine as a modifier. In order to optimise the coating conditions, the influence of the alkoxide, water and modifier on the sol viscosity, thickness and appearance of the Fe2O3 films has been investigated. For comparison of the crystallisation and magnetic properties, powders of the same composition as the films have been also prepared by the sol-gel method. The BaM phase appears after annealing at 650 degrees C for 6 hours. The BaM film and powder, heated at 850 degrees C for 6 hours, give coercive force of about 3000 and 5500 Oe, respectively.