MgO-based magnetic tunnel junction sensors array for non-destructive testing applications: Journal of Applied Physics: Vol 115, No 17

Abstract

A MgO-based magnetic tunnel junction

(MTJ)

sensor including 72 MTJs in series with 50 × 50 μm² was successfully microfabricated. Due to a two-step annealing strategy, a linear transfer curve was obtained. The tunneling magnetoresistance (TMR) value is as high as 159% and the sensitivity reaches 2.9%/Oe. The field detectivity exhibits the lowest value at 1 V bias current, attaining 1.76 nT/Hz^0.5 and 170 pT/Hz^0.5 for 10 Hz and 1 kHz, respectively. The results show that the sensor could be applied in non-destructive testing systems which are used for detecting small defects inside conductive materials.

REFERENCES

1. N. A. Stutzke, S. E. Russek, D. P. Pappas, and M. Tondra, J. Appl. Phys. 97, 10Q107 (2005) https://doi.org/10.1063/1.1861375. Google ScholarScitation
2. M. Pelkner, A. Neubauer, V. Reimund, M. Kreutzbruck, and A. Schiitze, Sensors 12, 12169–12183 (2012). https://doi.org/10.3390/s120912169 , , Google ScholarCrossref
3. C. H. Smith, R. W. Schneider, and A. V. Pohm, J. Appl. Phys. 93, 6864–6866 (2003). https://doi.org/10.1063/1.1558248 , , Google ScholarScitation, CAS
4. B. Wincheski, F. Yu, J. Simpon, P. Williams, and K. Rackow, NDT&E Int. 43, 718–725 (2010). https://doi.org/10.1016/j.ndteint.2010.08.005 , , Google ScholarCrossref, CAS
5. P. P. Freitas, S. Cardoso, R. Ferreira, V. R. Martins, A. Guedes, F. Cardoso, J. Loureiro, R. Macedo, R. Chaves, and J. P. Amaral, J. SPIN 1(1), 71–91 (2011). https://doi.org/10.1142/S2010324711000070 , , Google ScholarCrossref, CAS
6. R. J. Janeiro, L. Gameiro, A. Lopes, S. Cardoso, R. Ferreira, E. Paz, and P. P. Freitas, IEEE Trans. Magn. 48, 4111–4114 (2012). https://doi.org/10.1109/TMAG.2012.2202887 , , Google ScholarCrossref, CAS
7. R. Guerrero, M. Pannetier-Lecoeur, C. Fermon, S. Cardoso, R. Ferreira, and P. P. Freitas, J. Appl. Phys. 105, 113922 (2009). https://doi.org/10.1063/1.3139284 , , Google ScholarScitation, ISI
8. W. Z. Zhang, Q. Hao, and G. Xiao, Phys. Rev. B 84, 094446 (2011). https://doi.org/10.1103/PhysRevB.84.094446 , , Google ScholarCrossref
9. J. M. Almeida, P. Wisniowski, and P. P. Freitas, IEEE Trans. Magn. 44, 2569–2572 (2008). https://doi.org/10.1109/TMAG.2008.2002604 , , Google ScholarCrossref, CAS
10. F. N. Hooge, T. G. M. Kleinpenning, and L. K. J. Vandamme, Rep. Prog. Phys.44, 479 (1981). https://doi.org/10.1088/0034-4885/44/5/001 , , Google ScholarCrossref
11. S. H. Liou, X. L. Yin, S. E. Russek, R. Heindl, F. C. S. Da Silva, J. Moreland, D. P. Pappas, L. Yuan, and J. Shen, IEEE Trans. Magn. 47, 3740–3743 (2011). https://doi.org/10.1109/TMAG.2011.2157997 , , Google ScholarCrossref
12. J. M. Almeida, R. Ferreira, P. P. Freitas, J. Langer, B. Ocker, and W. Maass, J. Appl. Phys. 99, 08B314 (2006). https://doi.org/10.1063/1.2172179 , , Google ScholarScitation
13. J. M. Almeida and P. P. Freitas, J. Appl. Phys. 105, 07E722 (2009). https://doi.org/10.1063/1.3077228 , , Google ScholarScitation
14. J. Y. Chen, N. Carroll, J. F. Feng, and J. M. D. Coey, Appl. Phys. Lett. 101, 262402 (2012). https://doi.org/10.1063/1.4773180 , , Google ScholarScitation
15. D. Mazumdar, W. F. Shen, X. Y. Liu, B. D. Schrag, M. Carter, and G. Xiao, J. Appl. Phys. 103, 113911 (2008). https://doi.org/10.1063/1.2939265 , , Google ScholarScitation
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