(001)-oriented FeAlSi polycrystalline thin films with a flat surface and B2-ordered structure were grown on thermally oxidized SiO₂ substrates using MgO buffer layers. The FeAlSi thin films composition-adjusted to the Sendust alloy exhibited a low coercivity (H_c) after the annealing process. We utilized these films as bottom electrodes of magnetic tunnel junctions (MTJs) and characterized their tunnel magnetoresistance (TMR) effect. The TMR effect was 35.9% at room temperature. In addition, the TMR ratio increased to 51.0% when a thin CoFeB layer was inserted into the FeAlSi/MgO interface, without degrading the small switching field of the FeAlSi electrode. These MTJs with a small switching field and relatively high TMR ratio using the FeAlSi electrode are promising for highly sensitive MTJ-based magnetic sensor devices.

中文翻译：

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FeAlSi电极在磁性隧道结中的隧道磁阻

使用MgO缓冲层在热氧化的SiO ₂衬底上生长具有（001）取向的具有平坦表面和B2有序结构的FeAlSi多晶薄膜。调整为Sendust合金成分的FeAlSi薄膜表现出低矫顽力（H _c）退火过程之后。我们将这些膜用作磁性隧道结（MTJ）的底部电极，并表征了其隧道磁阻（TMR）效应。在室温下，TMR效果为35.9％。另外，当将薄的CoFeB层插入FeAlSi / MgO界面时，TMR比增加到51.0％，而不会降低FeAlSi电极的小开关场。这些使用FeAlSi电极具有较小的开关场和较高的TMR比的MTJ有望用于高度灵敏的基于MTJ的磁传感器设备。