Skip to main content
SpringerLink
Log in

Dynamic observation of oxygen vacancies in hafnia layer by in situ transmission electron microscopy

  • Research Article
  • Published:
Nano Research Aims and scope Submit manuscript

Abstract

The charge-trapping process, with HfO2 film as the charge-capturing layer, has been investigated by using in situ electron energy-loss spectroscopy and in situ energy-filter image under positive external bias. The results show that oxygen vacancies are non-uniformly distributed throughout the HfO2 trapping layer during the programming process. The distribution of the oxygen vacancies is not the same as that of the reported locations of the trapped electrons, implying that the trapping process is more complex. These bias-induced oxygen defects may affect the device performance characteristics such as the device lifetime. This phenomenon should be considered in the models of trapping processes.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Log in via an institution

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Similar content being viewed by others

References

  1. Wegener, H. A. R.; Lincoln, A. J.; Pao, H. C.; O’Connell, M. R.; Oleksiak, R. E.; Lawrence, H. The variable threshold transistor, a new electrically-alterable, non-destructive readonly storage device. In 1967 International Electron Devices Meeting, Washington,DC,USA, 1967, pp 70.

    Chapter  Google Scholar 

  2. Yao, Y.; Li, C.; Huo, Z. L.; Liu, M.; Zhu, C. X.; Gu, C. Z.; Duan, X. F.; Wang, Y. G.; Gu, L.; Yu, R. C. In situ electron holography study of charge distribution in high-κ chargetrapping memory. Nat. Commun. 2013, 4, 2764.

    Google Scholar 

  3. Xiong, K.; Robertson, J.; Gibson, M. C.; Clark, S. J. Defect energy levels in HfO2 high-dielectric-constant gate oxide. Appl. Phys. Lett. 2005, 87, 183505.

    Article  Google Scholar 

  4. Shockley, W.; Read, W. T. Statistics of the recombinations of holes and electrons. Phys. Rev. 1952, 87, 835–842.

    Article  Google Scholar 

  5. Park, H.; Jo, M.; Choi, H.; Hasan, M.; Choi, R.; Kirsch, P. D.; Kang, C. Y.; Lee, B. H.; Kim, T. W.; Lee, T. et al. The effect of nanoscale nonuniformity of oxygen vacancy on electrical and reliability characteristics of HfO2 MOSFET devices. IEEE Electr. Dev. Lett. 2008, 29, 54–56.

    Article  Google Scholar 

  6. Sahoo, S. K.; Misra, D. Interfacial layer growth condition dependent carrier transport mechanisms in HfO2/SiO2 gate stacks. Appl. Phys. Lett. 2012, 100, 232903.

    Article  Google Scholar 

  7. Choi, E. A.; Chang, K. J. Charge-transition levels of oxygen vacancy as the origin of device instability in HfO2 gate stacks through quasiparticle energy calculations. Appl. Phys. Lett. 2009, 94, 122901.

    Article  Google Scholar 

  8. Gavartin, J. L.; Ramo, D. M.; Shluger, A. L.; Bersuker, G.; Lee, B. H. Negative oxygen vacancies in HfO2 as charge traps in high-κ stacks. Appl. Phys. Lett. 2006, 89, 082908.

    Article  Google Scholar 

  9. Cho, D. Y.; Lee, Y. J. M.; Oh, S. J.; Jang, H.; Kim, J. Y.; Park, J. H.; Tanaka, A. Influence of oxygen vacancies on the electronic structure of HfO2 films. Phys. Rev. B 2007, 76, 165411.

    Article  Google Scholar 

  10. Perevalov, T. V.; Aliev, V. Sh.; Gritsenko, V. A.; Saraev, A. A.; Kaichev, V. V. Electronic structure of oxygen vacancies in hafnium oxide. Microelectron. Eng. 2013, 109, 21–23.

    Article  Google Scholar 

  11. Zhang, W.; Hou, Z. F. Interaction and electronic structures of oxygen divacancy in HfO2. Phys. Stat. Sol. (b) 2013, 250, 352–355.

    Article  Google Scholar 

  12. Pandey, R. K.; Sathiyanarayanan, R.; Kwon, U.; Narayanan, V; Murali, K. V. R. M. Role of point defects and HfO2/TiN interface stoichiometry on effective work function modulation in ultra-scaled complementary metal-oxide-semiconductor devices. J. Appl. Phys. 2013, 114, 034505.

    Article  Google Scholar 

  13. Jang, J. H.; Jung, H. S.; Kim, J. H.; Lee, S. Y.; Hwang, C. S.; Kim, M. Investigation of oxygen-related defects and the electrical properties of atomic layer deposited HfO2 films using electron energy-loss spectroscopy. J. Appl. Phys. 2011, 109, 023718.

    Article  Google Scholar 

  14. Jo, M.; Park, H.; Chang, M.; Jung, H. S.; Lee, J. H.; Hwang, H. Oxygen vacancy induced charge trapping and positive bias temperature instability in HfO2 nMOSFET. Microelectron. Eng. 2007, 84, 1934–1937.

    Article  Google Scholar 

  15. Broqvist, P.; Pasquarello, A. Oxygen vacancy in monoclinic HfO2: A consistent interpretation of trap assisted conduction, direct electron injection, and optical absorption experiments. Appl. Phys. Lett. 2006, 89, 262904.

    Article  Google Scholar 

  16. Bersuker, G.; Gilmer, D. C.; Veksler, D.; Kirsch, P.; Vandelli, L.; Padovani, A.; Larcher, L.; McKenna, K.; Shluger, A.; Iglesias, V. et al. Metal oxide resistive memory switching mechanism based on conductive filament properties. J. Appl. Phys. 2011, 110, 124518.

    Article  Google Scholar 

  17. Yu, S. M.; Gao, B.; Dai, H. B.; Sun, B.; Liu, L. F.; Liu, X. Y.; Han, R. Q.; Kang, J. F.; Yu, B. Improved uniformity of resistive switching behaviors in HfO2 thin films with embedded Al layers. Electrochem. Solid-St. Lett. 2010, 13, H36–H38.

    Article  Google Scholar 

  18. Tran, X. A.; Zhu, W.; Liu, W. J.; Yeo, Y. C.; Nguyen, B. Y.; Yu, H. Y. Self-selection unipolar HfOx-based RRAM. IEEE Trans. Electr. Dev. 2013, 60, 391–395.

    Article  Google Scholar 

  19. Chen, Y. Y.; Goux, L.; Clima, S.; Govoreanu, B.; Degraeve, R.; Kar, G. S.; Fantini, A.; Groeseneken, G.; Wouters, D. J.; Jurczak, M. Endurance/retention trade-off on cap 1T1R bipolar RRAM. IEEE Trans. Electr. Dev. 2013, 60, 1114–1121.

    Article  Google Scholar 

  20. Lin, Y. S.; Zeng, F.; Tang, S. G.; Liu, H. Y.; Chen, C.; Gao, S.; Wang, Y. G.; Pan, F. Resistive switching mechanisms relating to oxygen vacancies migration in both interfaces in Ti/HfOx/Pt memory devices. J. Appl. Phys. 2013, 113, 064510.

    Article  Google Scholar 

  21. Zhang, H. W.; Liu, L. F.; Gao, B.; Qiu, Y. J.; Liu, X. Y.; Lu, J.; Han, R.; Kang, J. F.; Yu, B. Gd-doping effect on performance of HfO2 based resistive switching memory devices using implantation approach. Appl. Phys. Lett. 2011, 98, 042105.

    Article  Google Scholar 

  22. Lee, J.; Bourim, E. M.; Lee, W.; Park, J.; Jo, M.; Jung, S.; Shin, J.; Hwang, H. Effect of ZrOx/HfOx bilayer structure on switching uniformity and reliability in nonvolatile memory applications. Appl. Phys. Lett. 2010, 97, 172105.

    Article  Google Scholar 

  23. Yang, Y.; Lü, W. M.; Yao, Y.; Sun, J. R.; Gu, C. Z.; Gu, L.; Wang, Y. G.; Duan, X. F.; Yu, R. C. In situ TEM observation of resistance switching in titanate based device. Sci. Rep. 2013, 4, 3890.

    Google Scholar 

  24. Kwon, D. H.; Kim, K. M.; Jang, J. H.; Jeon, J. M.; Lee, M. H.; Kim, G. H.; Li, X. S.; Park, G. S.; Lee, B.; Han, S. et al. Atomic structure of conducting nanofilaments in TiO2 resistive switching memory. Nat. Nanotechnol. 2010, 5, 148–153.

    Article  Google Scholar 

  25. Park, G. S.; Kim, Y. B.; Park, S. Y.; Li, X. S.; Heo, S.; Lee, M. J.; Chang, M.; Kwon, J. H.; Kim, M.; Chung, U. I. et al. In situ observation of filamentary conducting channels in an asymmetric Ta2O5-x /TaO2-x bilayer structure. Nat. Commun. 2013, 4, 2382.

    Google Scholar 

  26. Liu, Q.; Sun, J.; Lv, H. B.; Long, S. B.; Yin, K. B.; Wan, N.; Li, Y. T.; Sun, L. T.; Liu, M. Real-time observation on dynamic growth/dissolution of conductive filaments in oxideelectrolyte- based ReRAM. Adv. Mater. 2012, 24, 1844–1849.

    Article  Google Scholar 

  27. Guedj, C.; Hung, L.; Zobelli, A.; Blaise, P.; Sottile, F.; Olevano, V. Evidence for anisotropic dielectric properties of monoclinic hafnia using valence electron energy-loss spectroscopy in high-resolution transmission electron microscopy and ab initio time-dependent density-functional theory. Appl. Phys. Lett. 2014, 105, 222904.

    Article  Google Scholar 

  28. Park, J.; Yang, M. Determination of complex dielectric functions at HfO2/Si interface by using STEM-VEELS. Micron 2009, 40, 365–369.

    Article  Google Scholar 

  29. Kang, Y. S.; Kim, D. K.; Kang, H. K.; Cho, S.; Choi, S.; Kim, H.; Seo, J. H.; Lee, J.; Cho, M. H. Defect states below the conduction band edge of HfO2 grown on InP by atomic layer deposition. J. Phys. Chem. C 2015, 119, 6001–6008.

    Article  Google Scholar 

  30. Sawa, A. Resistive switching in transition metal oxides. Mater. Today 2008, 11, 28–36.

    Article  Google Scholar 

  31. Bersuker, G.; Yum, J.; Vandelli, L.; Padovani, A.; Larcher, L.; Iglesias, V.; Porti, M.; Nafría, M.; McKenna, K.; Shluger A. et al. Grain boundary-driven leakage path formation in HfO2 dielectrics. Solid-State Electron. 2011, 65–66, 146–150.

    Article  Google Scholar 

  32. Lanza, M. A review on resistive switching in high-κ dielectrics: A nanoscale point of view using conductive atomic force microscope. Materials 2014, 7, 2155–2182.

    Article  Google Scholar 

  33. Broqvist, P.; Pasquarello, A. First principles investigation of defects at interfaces between silicon and amorphous high-κ oxides. Microelectron. Eng. 2007, 84, 2022–2027.

    Article  Google Scholar 

  34. Zhang, T.; Ou, X.; Zhang, W. F.; Yin, J.; Xia, Y. D.; Liu, Z. G. High-κ-rare-earth-oxide Eu2O3 films for transparent resistive random access memory (RRAM) devices. J. Phys. D: Appl. Phys. 2014, 47, 065302.

    Article  Google Scholar 

  35. Lyons, J. L.; Janotti, A.; Van de Walle, C. G. The role of oxygen-related defects and hydrogen impurities in HfO2 and ZrO2. Microelectron. Eng. 2011, 88, 1452–1456.

    Article  Google Scholar 

  36. Mao, L. F.; Wang, Z. O. First-principles simulations of the leakage current in metal-oxide-semiconductor structures caused by oxygen vacancies in HfO2 high-κ gate dielectric. Phys. Stat. Sol. (a) 2008, 205, 199–203.

    Article  Google Scholar 

  37. Nadimi, E.; Roll, G.; Kupke, S.; Öttking, R.; Plänitz, P.; Radehaus, C.; Schreiber, M.; Agaiby, R.; Trentzsch, M.; Knebel, S. et al. The degradation process of high-κ SiO2/HfO2 gate-stacks: A combined experimental and first principles investigation. IEEE Trans. Electr. Dev. 2014, 61, 1278–1283.

    Article  Google Scholar 

  38. Perevalov, T. V.; Gritsenko, V. A. Application and electronic structure of high-permittivity dielectrics. In Proceedings of the 2010 27th International Conference on Microelectronics Proceedings, Nis, Serbia, 2010, pp 123–126.

    Chapter  Google Scholar 

  39. Padovani, A.; Larcher, L.; Bersuker, G.; Pavan, P. Charge transport and degradation in HfO2 and HfOx dielectrics. IEEE Electr. Dev. Lett. 2013, 34, 680–682.

    Article  Google Scholar 

  40. Mao, L. F.; Wang, Z. O.; Wang, J. Y.; Zhu, C. Y. The conduction band alignment of HfO2 caused by oxygen vacancies and its effects on the gate leakage current in MOS structures. Eur. Phys. J. Appl. Phys. 2007, 40, 59–63.

    Article  Google Scholar 

  41. Mannequin, C.; Gonon, P.; Vallée, C.; Latu-Romain, L.; Bsiesy, A.; Grampeix, H.; Salaün, A.; Jousseaume, V. Stressinduced leakage current and trap generation in HfO2 thin films. J. Appl. Phys. 2012, 112, 074103.

    Article  Google Scholar 

  42. Egerton, R. F. Electron Energy-Loss Spectroscopy in the Electron Microscope; Springer: New York, USA, 1995.

    Book  Google Scholar 

Download references

Author information

Authors and Affiliations

  1. Beijing National Laboratory of Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China

    Chao Li, Yuan Yao, Xi Shen, Yanguo Wang, Junjie Li, Changzhi Gu & Richeng Yu

  2. Laboratory of Nano-Fabrication and Novel Devices Integrated Technology, Institute of Microelectronics, Chinese Academy of Sciences, Beijing, 100029, China

    Qi Liu & Ming Liu

Authors
  1. Chao Li
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Yuan Yao
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. Xi Shen
    View author publications

    You can also search for this author in PubMed Google Scholar

  4. Yanguo Wang
    View author publications

    You can also search for this author in PubMed Google Scholar

  5. Junjie Li
    View author publications

    You can also search for this author in PubMed Google Scholar

  6. Changzhi Gu
    View author publications

    You can also search for this author in PubMed Google Scholar

  7. Richeng Yu
    View author publications

    You can also search for this author in PubMed Google Scholar

  8. Qi Liu
    View author publications

    You can also search for this author in PubMed Google Scholar

  9. Ming Liu
    View author publications

    You can also search for this author in PubMed Google Scholar

Corresponding authors

Correspondence to Richeng Yu or Ming Liu.

Additional information

These authors contributed equally to this work.

Electronic supplementary material

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Li, C., Yao, Y., Shen, X. et al. Dynamic observation of oxygen vacancies in hafnia layer by in situ transmission electron microscopy. Nano Res. 8, 3571–3579 (2015). https://doi.org/10.1007/s12274-015-0857-0

Download citation

  • Received:

  • Revised:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s12274-015-0857-0

Keywords

Search

Navigation