Growth and characterization of thick oriented barium hexaferrite films on MgO (111) substrates

Highly oriented films of BaFe12O19 have been deposited onto MgO (111) subst rates by pulsed laser ablation deposition. In contrast to epitaxial BaFe12O 19 films grown on Al2O3 (001) substrates, these films experience an in-plan e biaxial compressive stress, and do not crack or delaminate to thicknesses of at least 28 mu m. X-ray diffraction, magnetometry, torque magnetometry, and ferrimagnetic resonance results all indicate excellent c-axis orientat ion normal to the film plane, and magnetic properties comparable to bulk va lues. The thickness and properties of these films approach those required f or applications in low-loss self-biased nonreciprocal microwave devices. (C ) 2000 American Institute of Physics. [S0003-6951(00)01324-3].