Vacuum Annealing Induced Room-Temperature Ferromagnetism in Co0.1 Ti0.9 O2-δ Films Prepared by Sol-Gel Method

摘要

The Co-doped TiO,2 films (Co,0.1 Ti,0.9 O,2-δ) are prepared on silicon substrates by sol-gel method and post annealing. The Co,0.1 Ti,0.9 O,2-δ film annealed in air is non-ferromagnetic at room temperature. After further annealed in a vacuum, the room-temperature ferromagnetism (RTFM) is observed. Experimental evidences show that the RTFM in the Co,0.1 Ti,0.9 O,2-δ film may come from the Co-doped TiO,2 matrix and is related to the oxygen vacancies created by vacuum annealing.