Microwave and magnetic properties of barium hexaferrite films having the c-axis in the film plane by liquid phase epitaxy technique

Abstract

We report the growth of thick barium hexaferrite (BaFe12O19,BaM) films on m-planes ([11_00] or [101_0]) sapphire (Al2O3) substrates by the liquid phase epitaxy deposition technique. The procedure entailed the deposition of seed layers of BaFe12O19 onto the substrate by the pulsed laser ablation deposition and then dipping the substrate into a molten flux for 2 h. The total thickness ranged from 60 μm to 200 μm. The vibrating sample magnetometer (VSM) measurement data showed that the film exhibited magnetic uniaxial anisotropy axis in the film plane. The coercive field was relatively small, range of Hc was from 0.007 kOe to 0.08 kOe, and the saturation magnetization (4πMs)≅4.42 kG. The ferrimagnetic resonance (FMR) linewidth (ΔH) at 59.9 GHz was ∼0.08 kOe. This value of ΔH should be contrasted with previous FMR linewidth measurement of films deposited by the PLD technique which showed a ΔH of ∼1.20 kOe.