Interfacial mixing in double-barrier magnetic tunnel junctions with amorphous NiFeSiB layers

B. S. Chun; S. P. Ko; J. Y. Hwang; J. R. Rhee; T. W. Kim; Y. K. Kim

doi:10.1016/j.jmmm.2006.10.683

Interfacial mixing in double-barrier magnetic tunnel junctions with amorphous NiFeSiB layers

B. S. Chun, S. P. Ko, J. Y. Hwang, J. R. Rhee, T. W. Kim, Y. K. Kim

Research output: Contribution to journal › Article › peer-review

Abstract

Double-barrier magnetic tunnel junctions (DMTJs) comprising Ta 45/Ru 9.5/IrMn 10/CoFe 7/AlO_x/free layer (CoFe 4/NiFeSiB 2/CoFe 4, CoFe 10, or NiFeSiB 10)/AlO_x/CoFe 7/IrMn 10/Ru 60 (nm) have been examined with an emphasis given on understanding the interfacial mixing effects. The DMTJ, consisted of NiFeSiB, shows low switching field and low bias voltage dependence because the amorphous NiFeSiB has lower M_S (=800 emu/cm³) and offers smoother interfaces than polycrystalline CoFe. An interesting feature observed in the CoFe/NiFeSiB/CoFe sandwich free layered DMTJ is the presence of a wavy MR transfer curve at high-resistance region. Because the polycrystalline CoFe usually grows into a columnar structure, diamagnetic CoSi, paramagnetic FeSi, and/or diamagnetic CoB might have been formed during the sputter-deposition process. By employing electron energy loss spectrometry (EELS) and Auger electron spectroscopy (AES), we were able to confirm that Si and B atoms were arranged evenly in the top and bottom portions of AlO_x/CoFe interfaces. This means that the interfacial mixing resulted in a distorted magnetization reversal process.

Original language	English
Pages (from-to)	e638-e640
Journal	Journal of Magnetism and Magnetic Materials
Volume	310
Issue number	2 SUPPL. PART 3
DOIs	https://doi.org/10.1016/j.jmmm.2006.10.683
Publication status	Published - 2007 Mar

Bibliographical note

Funding Information:
This work was supported by the Korea Ministry of Science and Technology under contract National Research Laboratory Program, by the National Program for Tera-level Nanodevices as a 21st Century Frontier Program, and by the Korea Research Foundation Grant (No. KRF-2005-015-C00157) funded by the Korean Government (MOEHRD).

Keywords

Intermixing
Magnetic tunnel junction
NiFeSiB

ASJC Scopus subject areas

Electronic, Optical and Magnetic Materials
Condensed Matter Physics

Access to Document

10.1016/j.jmmm.2006.10.683

Cite this

@article{f5a113d570cf43858b04179fc02b436b,

title = "Interfacial mixing in double-barrier magnetic tunnel junctions with amorphous NiFeSiB layers",

abstract = "Double-barrier magnetic tunnel junctions (DMTJs) comprising Ta 45/Ru 9.5/IrMn 10/CoFe 7/AlOx/free layer (CoFe 4/NiFeSiB 2/CoFe 4, CoFe 10, or NiFeSiB 10)/AlOx/CoFe 7/IrMn 10/Ru 60 (nm) have been examined with an emphasis given on understanding the interfacial mixing effects. The DMTJ, consisted of NiFeSiB, shows low switching field and low bias voltage dependence because the amorphous NiFeSiB has lower MS (=800 emu/cm3) and offers smoother interfaces than polycrystalline CoFe. An interesting feature observed in the CoFe/NiFeSiB/CoFe sandwich free layered DMTJ is the presence of a wavy MR transfer curve at high-resistance region. Because the polycrystalline CoFe usually grows into a columnar structure, diamagnetic CoSi, paramagnetic FeSi, and/or diamagnetic CoB might have been formed during the sputter-deposition process. By employing electron energy loss spectrometry (EELS) and Auger electron spectroscopy (AES), we were able to confirm that Si and B atoms were arranged evenly in the top and bottom portions of AlOx/CoFe interfaces. This means that the interfacial mixing resulted in a distorted magnetization reversal process.",

keywords = "Intermixing, Magnetic tunnel junction, NiFeSiB",

author = "Chun, {B. S.} and Ko, {S. P.} and Hwang, {J. Y.} and Rhee, {J. R.} and Kim, {T. W.} and Kim, {Y. K.}",

note = "Funding Information: This work was supported by the Korea Ministry of Science and Technology under contract National Research Laboratory Program, by the National Program for Tera-level Nanodevices as a 21st Century Frontier Program, and by the Korea Research Foundation Grant (No. KRF-2005-015-C00157) funded by the Korean Government (MOEHRD).",

year = "2007",

month = mar,

doi = "10.1016/j.jmmm.2006.10.683",

language = "English",

volume = "310",

pages = "e638--e640",

journal = "Journal of Magnetism and Magnetic Materials",

issn = "0304-8853",

publisher = "Elsevier B.V.",

number = "2 SUPPL. PART 3",

}

TY - JOUR

T1 - Interfacial mixing in double-barrier magnetic tunnel junctions with amorphous NiFeSiB layers

AU - Chun, B. S.

AU - Ko, S. P.

AU - Hwang, J. Y.

AU - Rhee, J. R.

AU - Kim, T. W.

AU - Kim, Y. K.

N1 - Funding Information: This work was supported by the Korea Ministry of Science and Technology under contract National Research Laboratory Program, by the National Program for Tera-level Nanodevices as a 21st Century Frontier Program, and by the Korea Research Foundation Grant (No. KRF-2005-015-C00157) funded by the Korean Government (MOEHRD).

PY - 2007/3

Y1 - 2007/3

N2 - Double-barrier magnetic tunnel junctions (DMTJs) comprising Ta 45/Ru 9.5/IrMn 10/CoFe 7/AlOx/free layer (CoFe 4/NiFeSiB 2/CoFe 4, CoFe 10, or NiFeSiB 10)/AlOx/CoFe 7/IrMn 10/Ru 60 (nm) have been examined with an emphasis given on understanding the interfacial mixing effects. The DMTJ, consisted of NiFeSiB, shows low switching field and low bias voltage dependence because the amorphous NiFeSiB has lower MS (=800 emu/cm3) and offers smoother interfaces than polycrystalline CoFe. An interesting feature observed in the CoFe/NiFeSiB/CoFe sandwich free layered DMTJ is the presence of a wavy MR transfer curve at high-resistance region. Because the polycrystalline CoFe usually grows into a columnar structure, diamagnetic CoSi, paramagnetic FeSi, and/or diamagnetic CoB might have been formed during the sputter-deposition process. By employing electron energy loss spectrometry (EELS) and Auger electron spectroscopy (AES), we were able to confirm that Si and B atoms were arranged evenly in the top and bottom portions of AlOx/CoFe interfaces. This means that the interfacial mixing resulted in a distorted magnetization reversal process.

AB - Double-barrier magnetic tunnel junctions (DMTJs) comprising Ta 45/Ru 9.5/IrMn 10/CoFe 7/AlOx/free layer (CoFe 4/NiFeSiB 2/CoFe 4, CoFe 10, or NiFeSiB 10)/AlOx/CoFe 7/IrMn 10/Ru 60 (nm) have been examined with an emphasis given on understanding the interfacial mixing effects. The DMTJ, consisted of NiFeSiB, shows low switching field and low bias voltage dependence because the amorphous NiFeSiB has lower MS (=800 emu/cm3) and offers smoother interfaces than polycrystalline CoFe. An interesting feature observed in the CoFe/NiFeSiB/CoFe sandwich free layered DMTJ is the presence of a wavy MR transfer curve at high-resistance region. Because the polycrystalline CoFe usually grows into a columnar structure, diamagnetic CoSi, paramagnetic FeSi, and/or diamagnetic CoB might have been formed during the sputter-deposition process. By employing electron energy loss spectrometry (EELS) and Auger electron spectroscopy (AES), we were able to confirm that Si and B atoms were arranged evenly in the top and bottom portions of AlOx/CoFe interfaces. This means that the interfacial mixing resulted in a distorted magnetization reversal process.

KW - Intermixing

KW - Magnetic tunnel junction

KW - NiFeSiB

UR - http://www.scopus.com/inward/record.url?scp=33847640521&partnerID=8YFLogxK

U2 - 10.1016/j.jmmm.2006.10.683

DO - 10.1016/j.jmmm.2006.10.683

M3 - Article

AN - SCOPUS:33847640521

SN - 0304-8853

VL - 310

SP - e638-e640

JO - Journal of Magnetism and Magnetic Materials

JF - Journal of Magnetism and Magnetic Materials

IS - 2 SUPPL. PART 3

ER -

Interfacial mixing in double-barrier magnetic tunnel junctions with amorphous NiFeSiB layers

Abstract

Bibliographical note

Keywords

ASJC Scopus subject areas

Access to Document

Other files and links

Fingerprint

Cite this