本實驗中，使用雷射脈衝沉積儀(Pulsed Laser Deposition，PLD)成長鉑(Pt)/鈷(Co)/氧化鎂(MgO)/鉭(Ta)之四層膜結構，藉由調控其中氧化鎂之厚度、以及其成長時之氧分壓，以及退火溫度，研究鉑(Pt)/鈷(Co)介面以及鈷(Co)/氧化鎂(MgO)介面因自旋軌道耦合(spin-orbit coupling，SOC)產生的磁垂直異向性(perpendicular magnetic anisotropy，PMA)。再以此垂直異向性之研究為基礎，探討此結構之自旋軌道轉矩(spin-orbit torque，SOT)之電性。調控四層膜結構中鉭(Ta)之厚度，研究鉭(Ta)厚度對此結構之自旋軌道轉矩的影響。

Compared to other random-access memory device, the magnetic random-access memory (MRAM) has more advantages including of non-volatility, faster data processing, higher integration density and lower power consumption. Therefore, the research of the perpendicular magnetic anisotropy (PMA) and spin-orbit torques (SOTs) is an important topic. In this study, the SOTs in Pt/Co/MgO /Ta multilayers are obtained by analyzing Hall measurement results. The PMA properties of Pt/Co/MgO /Ta multilayers are investigated as a function of the MgO thickness and its annealing temperature. A strong PMA is improved by post-annealing up to 450 °C due to the significant change in the Co/MgO interface. The spin Hall angle of the multilayers obtained from SOT results is constant because the MgO layers prevent the spin current in the multilayers.

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