,Interlayer Segregation of Cu Atoms in Metal Multilayers

• 作 者: 于广华 李明华 朱逢吾 姜宏伟 赖武彦 柴春林
• 机 构: Department of Materials Physics,University of Science and Technology Beijing Beijing,100083“,”Instit
• 出 处: 中国物理快报（英文版）
• 发表日期: 2001年9期

The experimental results show that the exchange coupling field Hex of NiFe/FeMn for Ta/NiFe/FeMn/Ta multilayers is higher than that for the spin valve multilayers Ta/NiFe/Cu/NiFe/FeMn/Ta. The composition and chemical states at the surface of Ta(12 nm)/NiFe( 7 nm), Ta(12 nm)/NiFe(7 nm)/Cu(4 nm) and Ta(12 nm)/NiFe(7 nm)/Cu(3nm)/NiFe(5 nm) were studied by using x-ray photoelectron spectroscopy. The results show that no element from the underlayers floats out or segregates to the surface for Ta(12nm)/NiFe(7nm), Ta(12nm)/NiFe(7nm)/Cu(4nm). However, Cu atoms segregate to the surface of Ta(12nm)/NiFe(7nm)/Cu(3nm)/NiFe(5nm) multilayers, I.e. To the NiFe/FeMn interface for Ta/NiFe/Cu/NiFe/FeMn/Ta multilayers. We believe that the presence of Cu atoms at the interface of NiFe/FeMn is one of the important factors which will cause the exchange coupling field Hex of Ta/NiFe/FeMn/Ta multilayers to be higher than that of Ta/NiFe/Cu/NiFe/FeMn/Ta multilayers.