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Title: Interlayer segregation of nonmagnetic metal spacers and its influence on exchange coupling in magnetic multilayers

Abstract

Two sets of NiFe/FeMn films with Ta and Ta/Cu buffer layers were prepared by magnetron sputtering to study the influence of different buffers on the exchange coupling process. The results show that the exchange bias field (H{sub ex}) of NiFe/FeMn films with a Ta/Cu buffer is lower than that of films with a Ta buffer. There is no apparent difference in the texture and roughness of films both with Ta and Ta/Cu buffers. However, the segregation of Cu atoms on the surface of NiFe in the trilayer of Ta/Cu/NiFe was found by using angle-resolved x-ray photoelectron spectroscopy (XPS). A decrease of H{sub ex} for NiFe/FeMn films with a Ta/Cu buffer layer is primarily caused by the segregation of Cu atoms to the interface of the NiFe and FeMn layers. In order to suppress the Cu segregation, we deposited Bi insetting layers at the interface of Cu and NiFe in Ta/Cu/NiFe/FeMn/Ta films and found that H{sub ex} of NiFe/FeMn can be doubled when the proper quantity of Bi is deposited. XPS analysis shows that Bi insetting layers deposited at the interface of Cu and NiFe effectively suppress the Cu segregation on the NiFe layer. As a result, H{sub ex} is increased.more » However, if the insetting Bi is deposited excessively, it will partially migrate to the FeMn layer, damaging the antiferromagnetic property of the FeMn layer, thereby resulting in decreased H{sub ex}. When Ag and Pb were deposited at the interface of Cu and NiFe in Ta/Cu/NiFe/FeMn/Ta films, similar experimental results were obtained.« less

Authors:
; ; ;  [1];  [2];  [2];  [2]
  1. Department of Materials Physics, University of Science and Technology Beijing, Beijing 100083 (China)
  2. (China)
Publication Date:
OSTI Identifier:
20982767
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 101; Journal Issue: 6; Other Information: DOI: 10.1063/1.2713949; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ANTIFERROMAGNETIC MATERIALS; ANTIFERROMAGNETISM; BUFFERS; COPPER; DEPOSITION; FERROMAGNETIC MATERIALS; LAYERS; MANGANESE ALLOYS; PERMALLOY; ROUGHNESS; SEGREGATION; SPUTTERING; TANTALUM; TEXTURE; THIN FILMS; X-RAY PHOTOELECTRON SPECTROSCOPY

Citation Formats

Li, M. H., Yu, G. H., Zhu, F. W., Lai, W. Y., College of Mechanical Engineering, South China University of Technology, Guangzhou 510640, Department of Materials Physics, University of Science and Technology Beijing, Beijing 100083, and Institute of Physics, Chinese Academy of Sciences, Beijing 100080. Interlayer segregation of nonmagnetic metal spacers and its influence on exchange coupling in magnetic multilayers. United States: N. p., 2007. Web. doi:10.1063/1.2713949.
Li, M. H., Yu, G. H., Zhu, F. W., Lai, W. Y., College of Mechanical Engineering, South China University of Technology, Guangzhou 510640, Department of Materials Physics, University of Science and Technology Beijing, Beijing 100083, & Institute of Physics, Chinese Academy of Sciences, Beijing 100080. Interlayer segregation of nonmagnetic metal spacers and its influence on exchange coupling in magnetic multilayers. United States. doi:10.1063/1.2713949.
Li, M. H., Yu, G. H., Zhu, F. W., Lai, W. Y., College of Mechanical Engineering, South China University of Technology, Guangzhou 510640, Department of Materials Physics, University of Science and Technology Beijing, Beijing 100083, and Institute of Physics, Chinese Academy of Sciences, Beijing 100080. Thu . "Interlayer segregation of nonmagnetic metal spacers and its influence on exchange coupling in magnetic multilayers". United States. doi:10.1063/1.2713949.
@article{osti_20982767,
title = {Interlayer segregation of nonmagnetic metal spacers and its influence on exchange coupling in magnetic multilayers},
author = {Li, M. H. and Yu, G. H. and Zhu, F. W. and Lai, W. Y. and College of Mechanical Engineering, South China University of Technology, Guangzhou 510640 and Department of Materials Physics, University of Science and Technology Beijing, Beijing 100083 and Institute of Physics, Chinese Academy of Sciences, Beijing 100080},
abstractNote = {Two sets of NiFe/FeMn films with Ta and Ta/Cu buffer layers were prepared by magnetron sputtering to study the influence of different buffers on the exchange coupling process. The results show that the exchange bias field (H{sub ex}) of NiFe/FeMn films with a Ta/Cu buffer is lower than that of films with a Ta buffer. There is no apparent difference in the texture and roughness of films both with Ta and Ta/Cu buffers. However, the segregation of Cu atoms on the surface of NiFe in the trilayer of Ta/Cu/NiFe was found by using angle-resolved x-ray photoelectron spectroscopy (XPS). A decrease of H{sub ex} for NiFe/FeMn films with a Ta/Cu buffer layer is primarily caused by the segregation of Cu atoms to the interface of the NiFe and FeMn layers. In order to suppress the Cu segregation, we deposited Bi insetting layers at the interface of Cu and NiFe in Ta/Cu/NiFe/FeMn/Ta films and found that H{sub ex} of NiFe/FeMn can be doubled when the proper quantity of Bi is deposited. XPS analysis shows that Bi insetting layers deposited at the interface of Cu and NiFe effectively suppress the Cu segregation on the NiFe layer. As a result, H{sub ex} is increased. However, if the insetting Bi is deposited excessively, it will partially migrate to the FeMn layer, damaging the antiferromagnetic property of the FeMn layer, thereby resulting in decreased H{sub ex}. When Ag and Pb were deposited at the interface of Cu and NiFe in Ta/Cu/NiFe/FeMn/Ta films, similar experimental results were obtained.},
doi = {10.1063/1.2713949},
journal = {Journal of Applied Physics},
number = 6,
volume = 101,
place = {United States},
year = {Thu Mar 15 00:00:00 EDT 2007},
month = {Thu Mar 15 00:00:00 EDT 2007}
}
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