自旋阀巨磁电阻传感单元线性处理研究

摘要

为研究自旋阀传感器单元自由层易轴取向对其线性度的影响,通过改变诱导磁场取向,制备了自由层易轴沿传感单元电阻条长轴与短轴的两组样品.基于传感单元巨磁电阻效应的测试,发现自由层易轴沿传感单元电阻条短轴的样品,其性能稳定,矫顽力和线性范围基本不受电阻条宽度的影响；而对于自由层易轴沿传感器电阻条长轴的样品,随电阻条宽度的减小,传感器单元的线性范围增大,矫顽力降低.基于能量最小原理,发现自由层形状各向异性能是决定传感单元的线性度的关键参数,通过对其调制,可有效控制巨磁电阻传感器的线性度.%For researching the effect of free layer easy axis orientation on linearity of spin valve sensor element, we made two groups of samples by changing the direction of induced magnetic field, with free layer along the long axis and short axis of the element. It was found that the samples with free layer easy axis along the short axis has stable performance, and their coercivity and linear range are independent of samples' width; for the samples with free layer easy axis along the long axis, their performance are dependent of samples' width. With decreasing the width, the sensor element's linear range increases, and the coercivity decreases, which is consistent with the effect of the shape anisotropy energy of free layer.