不同缓冲层对NiFe/FeMn双层膜交换耦合场的影响

Influence of Buffer Layers on Exchange Coupling Field of NiFe/FeMn Bilayers

采用磁控溅射方法制备了NiFe/FeMn双层膜 ,分别以Ta ,Cu作为缓冲层 ,Ta作为保护层。实验发现 ,以Ta为缓冲层的NiFe/FeMn双层膜的交换耦合场比以Cu为缓冲层的NiFe/FeMn双层膜的交换耦合场大 ,而矫顽力却很小。本文分别从织构、界面粗糙度、界面偏聚等几方面对其中的原因进行了分析。除不同缓冲层引起的织构、界面粗糙度不同对交换耦合场有影响外 。

The NiFe/FeMn bilayers were grown by magnetron sputtering with different buffer layers (Ta or Cu) and cover layers.Properties of these bilayers were studied with X ray diffraction,vibrating sample magnetoscopy,X ray photoelectron spectroscopy and atom force microscopy.The results show that the exchange coupling field of the NiFe/FeMn films with Ta buffer layer was higher than that of the films with Cu buffer layer,but the coercivity of the former was lower than that of the latter.We concluded that the buffer layer induced properties,such as the crystallographic texture,the interfacial roughness and the interface segregation,affect the exchange coupling fields of the bilayers to a varying degree.