TITLE

Magnetotransport properties of Co–Fe/Al–N/Co–Fe tunnel junctions with large tunnel magnetoresistance ratio

AUTHOR(S)
Tae Sick Yoon; Chong Oh Kim; Shoyama, Toshihiro; Tsunoda, Masakiyo; Takahashi, Migaku
PUB. DATE
July 2004
SOURCE
Applied Physics Letters;7/5/2004, Vol. 85 Issue 1, p82
SOURCE TYPE
Academic Journal
DOC. TYPE
Article
ABSTRACT
The magnetotransport properties of tunnel junctions with the structure of Ta 5 nm/Cu 20 nm/Ta 5 nm/Ni76Fe24 2 nm/Cu 5 nm/Mn75 Ir25 10 nm/Co71Fe29 4 nm/Al–N/Co71Fe29 4 nm/Ni76Fe2420 nm/Ta 5 nm were investigated. When the Al thickness, nitridation time, and annealing temperature were 1 nm(0.8 nm), 50 s(35 s), and 280 °C(300 °C), tunnel magnetoresistance (TMR) ratio and resistance-area product were 49%(34%) and 3×104 Ω μm2(1.5×104Ωμ m2), respectively. In order to clarify the annealing temperature dependence of TMR ratio, the local transport properties were studied using conducting atomic force microscope for Ta 5 nm/Cu 20 nm/Ta 5 nm/Ni76Fe24 2 nm/Cu 5 nm/Mn75Ir25 10 nm/Co71Fe29 4 nm/Al(0.8 nm)–N junction fabricated with the nitridation time of 35 s and Ar+N2 plasma as a function of annealing temperature. The large TMR at 300 °C, where the TMR ratio of the corresponding magnetic tunnel junction had the maximum value of 34%, could be well elucidated by the enhancement of the average barrier height [lowercase_phi_synonym]ave, and the reduction of its fluctuation. After annealing at 340 °C, the leakage current was observed and the TMR ratio decreased.
ACCESSION #
13605574

 

Related Articles

  • Co2MnSi Heusler alloy as magnetic electrodes in magnetic tunnel junctions. Kämmerer, S.; Thomas, A.; Hütten, A.; Reiss, G. // Applied Physics Letters;7/5/2004, Vol. 85 Issue 1, p79 

    As a consequence of the growing theoretical predictions of 100% spin-polarized half- and full-Heusler compounds over the past six years, Heusler alloys are among the most promising materials class for future magnetoelectronic and spintronic applications. We have integrated Co2MnSi, as a...

  • Spin-polarized tunneling between ferromagnetic films. Gu, R. Y.; Xing, D. Y.; Dong, Jinming // Journal of Applied Physics;12/15/1996, Vol. 80 Issue 12, p7163 

    Deals with a study which derived the general expressions for spin-polarized tunneling conductances and magnetoresistance (MR) in ferromagnetic/insulator/ferromagnetic junctions. Utilization of a tunneling Hamiltonian process in expression derivation; Discussion on the case of anti-parallel...

  • Giant tunnel magnetoresistance and high annealing stability in CoFeB/MgO/CoFeB magnetic tunnel junctions with synthetic pinned layer. Lee, Y. M.; Hayakawa, J.; Ikeda, S.; Matsukura, F.; Ohno, H. // Applied Physics Letters;7/24/2006, Vol. 89 Issue 4, p042506 

    We investigated the relationship between tunnel magnetoresistance (TMR) ratio and the crystallization of CoFeB layers through annealing in magnetic tunnel junctions (MTJs) with MgO barriers that had CoFe/Ru/CoFeB synthetic ferrimagnet pinned layers with varying Ru spacer thickness (tRu). The TMR...

  • Magnetoresistance of spin-dependent tunnel junctions with composite electrodes. Ho, C. H.; Lin, Minn-Tsong; Yao, Y. D.; Lee, S. F.; Liao, C. C.; Chen, F. R.; Kai, J. J. // Journal of Applied Physics;12/15/2001, Vol. 90 Issue 12, p6222 

    Spin-dependent tunnel junctions, Co/Al[sub 2]O[sub 3]/Co (CoFe)/NiFe, were fabricated to investigate the effect of the additional Co (CoFe) interlayer on tunneling magnetoresistance. The quality of the junction was examined with a cross-sectional image generated by high-resolution transmission...

  • Thermally stable exchange-biased magnetic tunnel junctions over 400 °C. Matsukawa, Nozomu; Odagawa, Akihiro; Sugita, Yasunari; Kawashima, Yoshio; Morinaga, Yasunori; Satomi, Mitsuo; Hiramoto, Masayoshi; Kuwata, Jun // Applied Physics Letters;12/16/2002, Vol. 81 Issue 25, p4784 

    Exchange-biased magnetic tunnel junctions (MTJs) with interposed Fe[sub 1 - x]Pt[sub x] metal alloy layers between the Al oxide barrier and the ferromagnetic electrodes maintain large tunneling magnetoresistance (TMR) after thermal treatment in excess of 400 °C, owing to an improved barrier...

  • Spin-polarized transport in diluted GaMnAs/AlAs/GaMnAs ferromagnetic semiconductor tunnel junctions. Tao, Y.C.; Hu, J.G.; Liu, H. // Journal of Applied Physics;7/1/2004, Vol. 96 Issue 1, p498 

    Taking into account the basic physics of diluted ferromagnetic semiconductors (DMS), in which the variation of the splitting energy with temperature is included, we apply a quantum-mechanical approach to studying the spin-polarized transport in GaMnAs/AlAs/GaMnAs DMS tunnel junctions. It is...

  • Current driven resistance changes in low resistance x area magnetic tunnel junctions with ultra-thin Al-Ox barriers. Deac, A.; Redon, O.; Sousa, R. C.; Dieny, B.; Nozières, J. P.; Zhang, Z.; Y. Liu; Freitas, P. P. // Journal of Applied Physics;6/1/2004, Vol. 95 Issue 11, p6792 

    Current induced resistance changes were investigated in magnetic tunnel junctions with ultrathin Al-Ox barriers. The nonuniformity of the insulator induced a strong coupling between the two magnetic electrodes and no magnetoresistance. However, the current-voltage (I–V) characteristics at...

  • Magnetic noise evolution in CoFeB/MgO/CoFeB tunnel junctions during annealing. Stearrett, Ryan; Wang, W. G.; Shah, L. R.; Xiao, J. Q.; Nowak, E. R. // Applied Physics Letters;12/13/2010, Vol. 97 Issue 24, p243502 

    We report on the evolution of equilibrium magnetoresistive (MR) 1/f noise due to the exchange-biased magnetic layer in MgO-based magnetic tunnel junctions as a function of annealing time at 380 and 430 °C. The resistance susceptibility and MR noise are observed to increase rapidly with...

  • Magnetoresistance of ferromagnetic tunnel junctions with Al[sub 2]O[sub 3] barriers formed by rf sputter etching in Ar/O[sub 2] plasma. Nassar, J.; Hehn, M.; Vaure`s, A.; Petroff, F.; Fert, A. // Applied Physics Letters;8/3/1998, Vol. 73 Issue 5 

    Co/Al[sub 2]O[sub 3]/Ni[sub 80]Fe[sub 20] tunnel junctions were grown by sputtering at room temperature on glass and Si substrates, the barrier being formed by rf sputter etching of aluminum in a Ar/O[sub 2] plasma. The resistance is controlled for a given junction area by adjusting the oxide...

Share

Read the Article

Courtesy of VIRGINIA BEACH PUBLIC LIBRARY AND SYSTEM

Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics