Physical properties of Al doped Ba hexagonal ferrite thin films

摘要: We developed the thin film microwave magnetic material, M-type barium hexagonal ferrite (BaM) doped with Al, for signal processing devices operating above 40 GHz little to no applied field. Al was chosen as dopant material because it significantly increases already strong anisotropy field of BaM. A series BaAlxFe12-xO19 samples, x ranging from 0 2 in 0.25 steps, were deposited on Pt templates using a metal-organic decomposition growth technique. The resulting films are polycrystalline and highly textured, c-axis directed out plane. These also self-biasing; easy axis hysteresis loops have high squareness ratio, s, 0.83-0.92 range. As expected, x, 1.34 2.19 × 106 A/m (16.9-27.5 kOe) x = 0-2, while saturation magnetization Ms decreases 0.334 0.175 × 106 A/m (4πMs = 4.2-2.2 kG) x = 0-2. values measured at room temperature, but tem...