4英寸热氧化硅衬底上磁性隧道结的微制备

Microfabrication of magnetic tunnel junctions on 4-inch Si/SiO_2 substrate

就如何在 4英寸热氧化硅衬底上沉积高质量的磁性隧道结纳米多层薄膜材料和如何利用光刻方法微加工制备均匀性较好的磁性隧道结方面做了初步研究 ,并对磁性隧道结的磁电性质及其工作特性进行了初步测量和讨论 .利用现有的光刻设备和工艺条件在 4英寸热氧化硅衬底上直接制备出的磁性隧道结 ,其结电阻与面积的积矢的绝对误差在 10 %以内 ,隧穿磁电阻的绝对误差在 7%以内 ,样品的磁性隧道结性质具有较好的均匀性和一致性 。

Magnetic tunnel junctions (MTJs) with different sizes from 5μm×5μm to 15μm×60μm were fabricated on 4_inch Si/SiO 2 substrates. Their magnetoelectronic properties were investigated using the four_probe measuring system. The typical values of junction resistance_area product and tunneling magnetoresistance (TMR) ratio of the MTJs are 16 kΩμm 2 and 18% respectively. The absolute errors of junction resistance_area product and TMR ratio are within 10% and 7% respectively for all the MTJs. All of the MTJs fabricated and measured show a good uniformity. Our experimental results show that such MTJs can be used to fabricate the prototype demonstration devices for magnetoresistive random access memory.