Skip to main content
Log in

Ultrascalability and electron transport properties of ultra-thin film phase change material Ge2Sb2Te5

  • Regular Article
  • Published:
The European Physical Journal B Aims and scope Submit manuscript

Abstract

In the present work, we have used ab initio molecular dynamics (AIMD) and non-equilibrium Green’s function (NEGF) formalism to investigate the scaling behavior of electron transport in ultra-thin films of Ge2Sb2Te5 (GST). The relation between the thickness of GST and its electron transport properties are studied in both crystalline (c-GST) and amorphous (a-GST) phases. For thin films with lower than 36 Å thickness, we have observed a dramatic increase in the conductivity of the amorphous phase and an associated reduction in the conductance contrast between the two phases. Metal-induced gap states (MIGS) near the electrodes are observed in the density of states and the transmission coefficient of a-GST. The disappearance of the bandgap of a-GST due to the overlap of MIGS is responsible for the sharp reduction of crystalline to amorphous conductance ratio (ON/OFF). The ON/OFF ratio of the devices is about one order of magnitude upon downscaling the ultra-thin film of the active bit to 36 Å. This estimation is the ultimate scalability for the simulated PCM device. When the thickness of GST further scales down, the reliable read operation is not possible. Our results show very good agreement with experimental work and it seems promising to engineers and designers of ultra-thin PCM devices.

Graphical abstract

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

Access this article

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

Instant access to the full article PDF.

Similar content being viewed by others

References

  1. V.L. Deringer, R. Dronskowski, M. Wuttig, Adv. Funct. Mater. 25, 6343 (2015)

    Article  Google Scholar 

  2. J. Liang, R.G.D. Jeyasingh, H.Y. Chen, H.S.P. Wong, IEEE Trans. Electron Dev. 59, 1155 (2012)

    Article  ADS  Google Scholar 

  3. F. Xiong, A.D. Liao, D. Estrada, E. Pop, Science 332, 568 (2011)

    Article  ADS  Google Scholar 

  4. F. Xiong, M.H. Bae, Y. Dai, A.D. Liao, A. Behnam, E.A. Carrion, S. Hong, D. Ielmini, E. Pop, Nano Lett. 13, 464 (2013)

    Article  ADS  Google Scholar 

  5. A. Liao, Y. Zhao, E. Pop, Phys. Rev. Lett. 101, 256804 (2008)

    Article  ADS  Google Scholar 

  6. D. Loke, T.H. Lee, W.J. Wang, L.P. Shi, R. Zhao, Y.C. Yeo, T.C. Chong, S.R. Elliott, Science 336, 1566 (2012)

    Article  ADS  Google Scholar 

  7. W. Wang, D. Loke, L. Shi, R. Zhao, H. Yang, L.T. Law, L.T. Ng, K.G. Lim, Y.C. Yeo, T.C. Chong, A.L. Lacaita, Sci. Rep. 2, 360 (2012)

    Article  Google Scholar 

  8. J. Liu, M.P. Anantram, J. Appl. Phys. 113, 063711 (2013)

    Article  ADS  Google Scholar 

  9. J. Liu, X. Xu, M.P. Anantram, J. Comput. Electr. 13, 620 (2014)

    Article  Google Scholar 

  10. J. Liu, X. Xu, M.P. Anantram, IEEE Electr. Dev. Lett. 35, 533 (2014)

    Article  ADS  Google Scholar 

  11. S.G. Sarwat, P. Gehring, G. Rodriguez Hernandez, J.H. Warner, G.A.D. Briggs, J.A. Mol, H. Bhaskaran, Nano Lett. 17, 3688 (2017)

    Article  ADS  Google Scholar 

  12. S. Kim, B.J. Bae, Y. Zhang, R.G.D. Jeyasingh, Y. Kim, I.G. Baek, S. Park, S.W. Nam, H.S.P. Wong, IEEE Trans. Electr. Dev. 58, 1483 (2011)

    Article  ADS  Google Scholar 

  13. R.E. Simpson, M. Krbal, P. Fons, A.V. Kolobov, J. Tominaga, T. Uruga, H. Tanida, Nano Lett. 10, 414 (2010)

    Article  ADS  Google Scholar 

  14. N. Yamada, T. Matsunaga, J. Appl. Phys. 88, 7020 (2000)

    Article  ADS  Google Scholar 

  15. B. Zhang, W. Zhang, Z. Shen, Y. Chen, J. Li, S. Zhang, Z. Zhang, M. Wuttig, R. Mazzarello, E. Ma, X. Han Zhang, Appl. Phys. Lett. 108, 191902 (2016)

    Article  ADS  Google Scholar 

  16. W.K. Njoroge, H.W. Woltgens, M. Wuttig, J. Vacuum Sci. Technol. A: Vacuum Surfaces Films 20, 230 (2002)

    ADS  Google Scholar 

  17. J.M. Soler, E. Artacho, J.D. Gale, A. Garcia, J. Junquera, P. Ordejon, D. Sanchez-Portal, J. Phys.: Condens. Matter 14, 2745 (2002)

    ADS  Google Scholar 

  18. J. Taylor, H. Guo, J. Wang, Phys. Rev. B 63, 121104 (2001)

    Article  ADS  Google Scholar 

  19. M. Sato, T. Matsunaga, T. Kouzaki, N. Yamada, MRS Online Proc. Libr. Arch. 803, (2003)

  20. J. Akola, R.O. Jones, J. Phys.: Condens. Matter 20, 465103 (2008)

    ADS  Google Scholar 

  21. A. Roohforouz, A.A. Shokri, AIP Adv. 9, 055120 (2019)

    Article  ADS  Google Scholar 

  22. M. Brandbyge, J.L. Mozos, P. Ordejon, J. Taylor, K. Stokbro, Phys. Rev. B 65, 165401 (2002)

    Article  ADS  Google Scholar 

  23. N. Trouillier, J.L. Martins, Phys. Rev. B 43, 1993 (1991)

    Article  ADS  Google Scholar 

  24. J.P. Perdew, K. Burke, M. Ernzerhof, Phys. Rev. Lett. 77, 3865 (1996)

    Article  ADS  Google Scholar 

  25. S. Datta,Electronic transport in mesoscopic systems (Cambridge University Press, Cambridge, UK, 1997)

  26. M.P. Anantram, M.S. Lundstrom, D.E Nikonov, Proc. IEEE 96, 1511 (2008)

    Article  Google Scholar 

  27. R. Landauer, IBM J. Res. Dev. 1, 223 (1957)

    Article  Google Scholar 

  28. M. Büttiker, Phys. Rev. Lett. 57, 1761 (1986)

    Article  ADS  Google Scholar 

  29. S. Raoux, M. Wuttig,Phase Change Materials Science and Applications (Springer, New York, 2009)

  30. V. Heine, Phys. Rev. A 138, 1689 (1965)

    Article  ADS  Google Scholar 

  31. W. Monch, inElectronic structure of metal-semiconductor contacts (Springer Science and Business Media, 2012), Vol. 4

  32. A. Pirovano, A.L. Lacaita, A. Benvenuti, F. Pellizzer, R. Bez, IEEE Trans. Electr. Dev. 51, 452 (2004)

    Article  ADS  Google Scholar 

  33. M. Kiguchi, K. Saiki, J. Surf. Sci. Nanotechnol. 2, 191 (2004)

    Article  Google Scholar 

  34. T. Frederiksen, M. Paulsson, M. Brandbyge, A.P. Jauho, Phys. Rev. B 75, 205413 (2007)

    Article  ADS  Google Scholar 

  35. M. Paulsson, M. Brandbyge, Phys. Rev. B 76, 115117 (2007)

    Article  ADS  Google Scholar 

Download references

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Aliasghar Shokri.

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Roohforouz, A., Shokri, A. Ultrascalability and electron transport properties of ultra-thin film phase change material Ge2Sb2Te5. Eur. Phys. J. B 92, 279 (2019). https://doi.org/10.1140/epjb/e2019-100353-1

Download citation

  • Received:

  • Revised:

  • Published:

  • DOI: https://doi.org/10.1140/epjb/e2019-100353-1

Keywords

Navigation