PtMn层厚度对NiFe/PtMn双层膜交换偏置形成及热稳定性的影响

The formation and thermal stability of exchange bias in NiFe/PtMn bilayers

采用磁控溅射的方法制备了一组以(Ni0·81Fe0·19)1-xCrx作为缓冲层的NiFe/PtMn双层膜样品,研究了NiFe/PtMn双层膜的形成过程和热稳定性.实验表明,Cr成分的不同会引起NiFe/PtMn双层膜中PtMn层晶粒尺寸的不同,使NiFe/PtMn双层膜的交换偏置场与PtMn层厚度之间呈现不同的变化关系.热稳定性实验表明,PtMn晶粒尺寸较大的样品,出现交换偏置现象所需要的临界厚度较小,热稳定性好,这与Mauri的理论模型一致.

（Ni0.81Fe0.19）1-x Crx/NiFe/PtMn films were prepared by magnetron sputtering. The formation and thermal stablitity of NiFe/PtMn bilayers were systematically investigated. The experiment shows that the grain size of PtMn layer depends strongly on the change in Cr eoncent ration. Thermal stability of exchange bias indicates that （Ni0.81 Fe0.19 ）1-x, Crx/NiFe/PtMn films with larger PtMn grains have a higher blocking temperature, and the bigger grain size is helpful in reducing the critical thickness of PtMn layer, which is consistent with Mauri＇s model.