Transmission electron microscopy of Co2(Cr1-xFex)Al sputtered films and their magnetic tunneling junctions

Y. K. Takahashi; T. Ohkubo; K. Hono; S. Okamura; N. Tezuka; K. Inomata

doi:10.1016/j.jmmm.2006.09.023

Transmission electron microscopy of Co₂(Cr_1-xFe_x)Al sputtered films and their magnetic tunneling junctions

Y. K. Takahashi, T. Ohkubo, K. Hono, S. Okamura, N. Tezuka, K. Inomata

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

7 Citations (Scopus)

Abstract

The microstructures of Co₂FeAl and Co₂(Cr_0.4Fe_0.6)Al sputtered films and of their magnetic tunnel junctions (MTJs) have been investigated to discuss the possible reasons for an unexpectedly low tunneling magnetoresistance (TMR). The structure of the Co₂FeAl film changed from B2 to L2₁ with increasing substrate temperature, while that of the Co₂(Cr_0.4Fe_0.6)Al film remained B2 up to 500 °C. The thermodynamically predicted phase separation was not observed in the films. The low TMR values obtained from the MTJs using the Co₂FeAl and Co₂(Cr_0.4Fe_0.6)Al films are attributed to the low-spin polarization expected from the low degree of order in these films. The TMR values depend sensitively on the interfacial structure of the tunnel junctions when the degree of order of the film is low.

Original language	English
Pages (from-to)	378-382
Number of pages	5
Journal	Journal of Magnetism and Magnetic Materials
Volume	313
Issue number	2
DOIs	https://doi.org/10.1016/j.jmmm.2006.09.023
Publication status	Published - 2007 Jun

Keywords

Co(CrFe)Al film
Magnetic tunnel junctions
Microstructure

Access to Document

10.1016/j.jmmm.2006.09.023

Cite this

@article{addba87edef14c65b8ce9e575b5723e8,

title = "Transmission electron microscopy of Co2(Cr1-xFex)Al sputtered films and their magnetic tunneling junctions",

abstract = "The microstructures of Co2FeAl and Co2(Cr0.4Fe0.6)Al sputtered films and of their magnetic tunnel junctions (MTJs) have been investigated to discuss the possible reasons for an unexpectedly low tunneling magnetoresistance (TMR). The structure of the Co2FeAl film changed from B2 to L21 with increasing substrate temperature, while that of the Co2(Cr0.4Fe0.6)Al film remained B2 up to 500 °C. The thermodynamically predicted phase separation was not observed in the films. The low TMR values obtained from the MTJs using the Co2FeAl and Co2(Cr0.4Fe0.6)Al films are attributed to the low-spin polarization expected from the low degree of order in these films. The TMR values depend sensitively on the interfacial structure of the tunnel junctions when the degree of order of the film is low.",

keywords = "Co(CrFe)Al film, Magnetic tunnel junctions, Microstructure",

author = "Takahashi, {Y. K.} and T. Ohkubo and K. Hono and S. Okamura and N. Tezuka and K. Inomata",

note = "Funding Information: This work was in part supported by the Ministry of Education, Science, Sports, and Culture, Grant-in-Aid for Scientific Research (B), 17360346, 2005.",

year = "2007",

month = jun,

doi = "10.1016/j.jmmm.2006.09.023",

language = "English",

volume = "313",

pages = "378--382",

journal = "Journal of Magnetism and Magnetic Materials",

issn = "0304-8853",

publisher = "Elsevier",

number = "2",

}

TY - JOUR

T1 - Transmission electron microscopy of Co2(Cr1-xFex)Al sputtered films and their magnetic tunneling junctions

AU - Takahashi, Y. K.

AU - Ohkubo, T.

AU - Hono, K.

AU - Okamura, S.

AU - Tezuka, N.

AU - Inomata, K.

N1 - Funding Information: This work was in part supported by the Ministry of Education, Science, Sports, and Culture, Grant-in-Aid for Scientific Research (B), 17360346, 2005.

PY - 2007/6

Y1 - 2007/6

N2 - The microstructures of Co2FeAl and Co2(Cr0.4Fe0.6)Al sputtered films and of their magnetic tunnel junctions (MTJs) have been investigated to discuss the possible reasons for an unexpectedly low tunneling magnetoresistance (TMR). The structure of the Co2FeAl film changed from B2 to L21 with increasing substrate temperature, while that of the Co2(Cr0.4Fe0.6)Al film remained B2 up to 500 °C. The thermodynamically predicted phase separation was not observed in the films. The low TMR values obtained from the MTJs using the Co2FeAl and Co2(Cr0.4Fe0.6)Al films are attributed to the low-spin polarization expected from the low degree of order in these films. The TMR values depend sensitively on the interfacial structure of the tunnel junctions when the degree of order of the film is low.

AB - The microstructures of Co2FeAl and Co2(Cr0.4Fe0.6)Al sputtered films and of their magnetic tunnel junctions (MTJs) have been investigated to discuss the possible reasons for an unexpectedly low tunneling magnetoresistance (TMR). The structure of the Co2FeAl film changed from B2 to L21 with increasing substrate temperature, while that of the Co2(Cr0.4Fe0.6)Al film remained B2 up to 500 °C. The thermodynamically predicted phase separation was not observed in the films. The low TMR values obtained from the MTJs using the Co2FeAl and Co2(Cr0.4Fe0.6)Al films are attributed to the low-spin polarization expected from the low degree of order in these films. The TMR values depend sensitively on the interfacial structure of the tunnel junctions when the degree of order of the film is low.

KW - Co(CrFe)Al film

KW - Magnetic tunnel junctions

KW - Microstructure

UR - http://www.scopus.com/inward/record.url?scp=34047260748&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=34047260748&partnerID=8YFLogxK

U2 - 10.1016/j.jmmm.2006.09.023

DO - 10.1016/j.jmmm.2006.09.023

M3 - Article

AN - SCOPUS:34047260748

SN - 0304-8853

VL - 313

SP - 378

EP - 382

JO - Journal of Magnetism and Magnetic Materials

JF - Journal of Magnetism and Magnetic Materials

IS - 2

ER -

Transmission electron microscopy of Co₂(Cr_1-xFe_x)Al sputtered films and their magnetic tunneling junctions

Abstract

Keywords

Access to Document

Other files and links

Fingerprint

Cite this