Effect of Annealing on the Magnetic Properties of Y_3Fe_5O_(12) and Y_(2.95)La_(0.05)Fe_(4.7)Ga_(0.3)O_(12) Films

摘要

We have studied the effect of high-temperature (1273-1673 K) and low-temperature (523-873 K) anneals in air, O_2, and N_2 on the magnetic properties of Y_3Fe_5O_(12) and Y_(2.95)La_(0.05)Fe_(4.7)Ga_(0.3)O_(12) garnet ferrite films. The films, 5-15 urn in thickness, were grown on (11 l)-oriented gadolinium gallium garnet (Gd_3Ga_5O_(12)) substrates by liquid phase epitaxy. High-temperature annealing was shown to change the saturation magnetization and increase the ferromagnetic resonance linewidth AH of the films. Low-temperature annealing at 723 K in flowing dry oxygen for 20 h reduces the AH of the ferromagnetic resonance by 18-25% and makes it insensitive to changes in temperature and ambient humidity.