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Preparation and effect of oxygen annealing on the electrical and magnetic properties of epitaxial (0001) Zn1−x Co x O thin films

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Abstract

Epitaxial (0001)-oriented Zn1−x Co x O ( x = 0.01, 0.05 and 0.1) thin films were grown on c-sapphire substrates by pulsed laser deposition. The XRD analysis, optical transmittance and XPS measurements revealed that the Co2+ substituted Zn2+ ions were incorporated into the lattice of ZnO in Zn1−x Co x O thin films. The electrical properties measurements revealed that the Co concentration had a nonmonotonic influence on the electrical properties of the Zn1−x Co x O thin films due to the defects resulted from imperfections induced by Co substitution. The resistivity remarkably increased and the carrier concentration remarkably decreased in Zn1−x Co x O thin films after oxygen annealing at 600 ° under 15 Pa O2 pressure for 60 mins. Room-temperature ferromagnetic was observed and the ferromagnetic Co amount was smaller than the nominal Co concentration for Zn1−x Co x O samples before oxygen annealing. After oxygen annealing, the Zn1−x Co x O thin films exhibited paramagnetic behavior. It is suggested that the room-temperature ferromagnetic of Zn1−x Co x O thin films may attribute to defects or carriers induced mechanism.

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References

  1. T Dietl, H Ohno, F Matsukura, et al. Zener Model Description of Ferromagnetism in Zinc-Blende Magnetic Semiconductors[J]. Science, 2000, 287: 1 019–1 022

    Article  CAS  Google Scholar 

  2. K Sato, H Katayama-Yoshida. Material Design for Transparent Ferromagnets with ZnO-Based Magnetic Semiconductors[J]. Jpn. J. Appl. Phys., 2000, 39: L555–L558

    Article  CAS  Google Scholar 

  3. M Bouloudenine, N Viart, S Colis, et al. Antiferromagnetism in Bulk Zn1−x CoxO Magnetic Semiconductors Prepared by the Coprecipitation Technique[J]. Appl. Phys. Lett., 2005, 87(5): 052501

    Article  Google Scholar 

  4. J Alaria, H Bieber, S Colis, et al. Absence of Ferromagnetism in Aldoped Zn0.9Co0.1O Diluted Magnetic Semiconductors[J]. Appl. Phys. Lett., 2006, 88(11): 112 503

    Article  Google Scholar 

  5. H J Lee, S Y Jeong, C R Cho, et al. Study of Diluted Magnetic Semiconductor: Co-doped ZnO[J]. Appl. Phys. Lett., 2002, 81(21): 4 020–4 022

    CAS  Google Scholar 

  6. K J Kim, Y R Park. Spectroscopic Ellipsometry Study of Optical Transitions in Zn1−x CoxO Alloys[J]. Appl. Phys. Lett., 2002, 81(21): 1 420–1 422

    Article  CAS  Google Scholar 

  7. Y Belghazi, D Stoeffler, S Colis, et al. Magnetic Properties of Aldoped Zn0.95Co0.05O Films: Experiment and Theory[J]. J. Appl. Phys., 2009, 105(11): 113 904

    Article  Google Scholar 

  8. Z L Lu, H S Hsu, Y H Tzeng, et al. The Origins of Ferromagnetism in Co-doped ZnO Single Crystalline Films: From Bound Magnetic Polaron to Free Carrier-mediated Exchange Interaction[J]. Appl. Phys. Lett., 2009, 95(10): 102 501

    Google Scholar 

  9. S Luo, L Zhang, C Wang, et al. Fabrication and Characterizations of Zn1−x CoxO Bulk Ceramics Prepared by Solid State Reaction Combined with Spark Plasma Sintering[J]. J. Mater. Sci.: Mater. Electron., 2012, 23(8): 1 477–1 484

    Article  CAS  Google Scholar 

  10. J Narayan, K Dovidenko, A K Sharma, et al. Defects and Interfaces in Epitaxial ZnO/α-Al2O3 and AlN/ZnO/α-Al2O3 Heterostructures[J]. J. Appl. Phys., 1998, 84(5): 2 597–2 601

    Article  CAS  Google Scholar 

  11. Y D Kim, S L Cooper, M V Klein, et al. Spectroscopic Ellipsometry Study of the Diluted Magnetic Semiconductor System Zn(Mn, Fe, Co) Se[J]. Phys. Rev. B, 1994, 49(3): 1 732–1 742

    CAS  Google Scholar 

  12. Y R Lee, A K Ramdas, R L Aggarwal. Energy Gap, Excitonic, and “Internal” Mn2+ Optical Transition in Mn-based II-VI Diluted Magnetic Semiconductors[J]. Phys. Rev. B, 1988, 38(15): 10 600–10 610

    Article  CAS  Google Scholar 

  13. P Koidl. Optical Absorption of Co2+ in ZnO[J]. Phys. Rev. B, 1977, 15(5): 2 493–2 499

    Article  CAS  Google Scholar 

  14. J F Moulder, W F Stickle, P E Sobol, et al. Handbook of X-ray Photo-Spectroscopy[M]. Minnesota: Perkin-Elmer, 1992

    Google Scholar 

  15. K R Kittilstved, N S Norberg, D R Gamelin. Chemical Manipulation of High-T C Ferromagnetism in ZnO Diluted Magnetic Semiconductors[J]. Phys. Rev. Lett., 2005, 94(14): 147 209

    Article  Google Scholar 

  16. X Xu, C Cao. Hydrothermal Synthesis of Co-doped ZnO Flakes with Room Temperature Ferromagnetism[J]. J. Alloy. Compd., 2010, 501(2): 265–268

    Article  CAS  Google Scholar 

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Authors and Affiliations

  1. State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan, 430070, China

    Sijun Luo  (罗嗣俊), Lianmeng Zhang  (张联盟), Chuanbin Wang, Xuan Zhou & Qiang Shen

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  1. Sijun Luo  (罗嗣俊)
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  2. Lianmeng Zhang  (张联盟)
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  3. Chuanbin Wang
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  4. Xuan Zhou
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  5. Qiang Shen
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Correspondence to Lianmeng Zhang  (张联盟).

Additional information

Funded by New Century Excellent Talents in University (No.NCET-10-0662), International Science and Technology Cooperation Project of Hubei Province (No.2010BFA017) and International Science & Technology Cooperation Program of China (No.2011DFA52650)

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Luo, S., Zhang, L., Wang, C. et al. Preparation and effect of oxygen annealing on the electrical and magnetic properties of epitaxial (0001) Zn1−x Co x O thin films. J. Wuhan Univ. Technol.-Mat. Sci. Edit. 28, 893–897 (2013). https://doi.org/10.1007/s11595-013-0788-0

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  • DOI: https://doi.org/10.1007/s11595-013-0788-0

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