Effect of oxygen vacancies in the magnetic properties of the amorphous CoFe2O4 films

Amorphous CoFe2O4 films with different thicknesses were deposited on MgO(001) substrates to examine the correlation between the oxygen vacancy and magnetic properties of the films. As the film thickness increased, the films became packed and smooth with well-defined interfaces. The magnetic hysteresis loop on the out-of-plane and in-plane showed an increased saturation magnetization and decreased coercivity when the film thickness was increased. Furthermore, the number of oxygen vacancies decreased with increasing films thickness. Those observations suggest that the presence of the correlation between the magnetic property variations and number of oxygen vacancies.