【摘要】 利用金属掩模法和Ir2 2 Mn78合金反铁磁钉扎层 ,制备了四种钉扎型的Py Al2 O3 Py ,Py Al2 O3 Co ,Co Al2 O3 Py和Co Al2 O3 Co磁性隧道结 ,坡莫合金的成分为Py =Ni79Fe2 1 .例如 :利用狭缝宽度为 1 0 0 μm的金属掩模 ,直接制备出室温隧穿磁电阻比值为 1 7 2 %的磁性隧道结Co Al2 O3 Co,其结电阻为 76Ω ,结电阻和结面积的积矢为 76× 1 0 4 Ωμm2 ,自由层的偏转场为 1 1 1 4A m ,并且在外加磁场 0— 1 1 1 4A·m- 1 之间时室温磁电阻比值从零跳跃增加到 1 7 2 % ,磁场灵敏度达到 0 1 % (1 0 3A·m- 1 ) .钉扎型Co Al2 O3 Py的隧穿磁电阻实验曲线具有较好的方形度 .结果表明 ,这种利用金属掩模法制备的钉扎型磁性隧道结亦可用于制备磁随机存储器等原型演示器件或其他种类原型磁敏传感器件更多还原

【Abstract】 Four types of pinned magnetic tunnel junctions (MTJs) with three key layer structures of Py/Al 2O 3/Py,Py/Al 2O 3/Co, Co/Al 2O 3/Py, Co/Al 2O 3/Co were fabricated using a contact shadow mask method and an antiferromagnetically pinned layer of Ir 22 Mn 78 . The slit width of the shadow mask is 100?μm, and the composition of permalloy is Py=Ni 79 Fe 21 .For example, the MTJs of Co/Al 2O 3/Co with a tunneling magnetoresistance (TMR) ratio of 17 2%, the junction resistance of 76?Ω, the resistance area product RS of 760?kΩμm 2, and the free layer reversal field of 1114?A·m -1 defined as the field where the TMR rises to 50% of the total jump were achieved at the as deposited state at room temperature. Furthermore, when the magnetic field increases from 0 to 1114?A·m -1 the TMR ratio jumps from 0 to 17 2% with one step, which shows that the magnetic field sensitivity of the junction reached at 0 1%/(10 3A·m -1 ). While, the TMR vs external filed H curves for the pinned MTJs of Co/Al 2O 3/Py show a good rectangular shape with a small free layer reversal filed of 1114?A·m -1 . Our experimental results show that such MTJs can be used to fabricate the magnetic field sensitive sensors or prototype demonstration devices of magnetoresistive random access memory.更多还原