Hostname: page-component-78c5997874-4rdpn Total loading time: 0 Render date: 2024-11-19T05:15:32.816Z Has data issue: false hasContentIssue false

Reconfiguration of van der Waals Gaps as the Key to Switching in GeTe/Sb2Te3 Superlattices

Published online by Cambridge University Press:  21 May 2018

A.V. Kolobov*
Affiliation:
Nanoelectronics Research Institute, National Institute of Advanced Industrial Science & Technology, Tsukuba Central 5, 1-1-1 Higashi, Ibaraki 305-8565, JAPAN
P. Fons
Affiliation:
Nanoelectronics Research Institute, National Institute of Advanced Industrial Science & Technology, Tsukuba Central 5, 1-1-1 Higashi, Ibaraki 305-8565, JAPAN
Y. Saito
Affiliation:
Nanoelectronics Research Institute, National Institute of Advanced Industrial Science & Technology, Tsukuba Central 5, 1-1-1 Higashi, Ibaraki 305-8565, JAPAN
J. Tominaga
Affiliation:
Nanoelectronics Research Institute, National Institute of Advanced Industrial Science & Technology, Tsukuba Central 5, 1-1-1 Higashi, Ibaraki 305-8565, JAPAN
*
Get access

Abstract

GeTe/Sb2Te3 superlattices, also known as interfacial phase-change memory (iPCM), exhibit significantly faster switching and are characterized by much lower power consumption and longer data retention compared to devices based on alloyed materials. In early work, the superior performance of iPCM was linked to a crystal-crystal transition between the SET and RESET states. As the primary mechanism, a change in the stacking order of Ge and Te planes within a GeTe block was suggested. Subsequent STEM studies on epitaxial GeTe/Sb2Te3 superlattices demonstrated that the GeTe blocks were not located between Sb2Te3 quintuple layers but, were incorporated inside the latter, providing a serious challenge to the early explanation. In this work, we demonstrate that changes associated with the reconstruction of the SbTe terminating layers nearest to van der Waals gap leads to a pronounced change in the density of states and can serve as an alternative explanation for a large property contrast between the SET and RESET states in GeTe/Sb2Te3 superlattices.

Type
Articles
Copyright
Copyright © Materials Research Society 2018 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Ovshinsky, S. R., Phys. Rev. Lett., 21, 14501453 (1968).CrossRefGoogle Scholar
Wuttig, M. and Yamada, N., Nature Mater., 6, 824832 (2007).CrossRefGoogle Scholar
Hady, F. T., Foong, A., Veal, B., and Williams, D., Proc. of the IEEE, 105, 18221833 (2017).CrossRefGoogle Scholar
Simpson, R. E., Fons, P., Kolobov, A. V., Fukaya, T., Krbal, M., Yagi, T., and Tominaga, J., Nature Nanotech., 6, 501505 (2011).CrossRefGoogle Scholar
Kolobov, A., Fons, P., Frenkel, A., Ankudinov, A., Tominaga, J., and Uruga, T., Nature Mater., 3, 703708 (2004).CrossRefGoogle Scholar
Kolobov, A. V., Fons, P., Tominaga, J., Hyot, B., and André, B., Nano Letters, 16, 48494856 (2016).CrossRefGoogle Scholar
Petrov, I., Imamov, R., and Pinsker, Z., Sov. Phys. Cryst., 13, 339344 (1968).Google Scholar
Sun, Z., Zhou, J., and Ahuja, R., Phys. Rev. Lett., 96, 055507 (2006).CrossRefGoogle Scholar
Yu, X. and Robertson, J., Sci. Rep., 5, 12612 (2015).CrossRefGoogle Scholar
Tominaga, J., Kolobov, A. V., Fons, P., Nakano, T., and Murakami, S., Adv. Mat. Interf., 1, 1300027 (2014).CrossRefGoogle Scholar
Kim, J., Kim, J., and Jhi, S.-H., Phys. Rev. B, 82, 201312 (2010).CrossRefGoogle Scholar
Momand, J., Wang, R., Boschker, J.E., Verheijen, M.A., Calarco, R., Kooi, B.J., Nanoscale 7, 1913619143 (2015)CrossRefGoogle Scholar
Kellner, J., Bihlmayer, G., Deringer, V. L., Liebmann, M., Pauly, C., Giussani, A., Boschker, J. E., Calarco, R., Dronskowski, R., and Morgenstern, M., Phys. Rev. B, 96, 245408 (2017).CrossRefGoogle Scholar
Küpers, M., Konze, P. M., Maintz, S., Steinberg, S., Mio, A. M., Cojocaru-Mirédin, O., Zhu, M., Müller, M., Luysberg, M., Mayer, J., Wuttig, M., and Dronskowski, R., Angew. Chem. Int. Edit., 56, 1020410208 (2017).CrossRefGoogle Scholar
Kolobov, A. V., Fons, P., Saito, Y., and Tominaga, J., ACS Omega, 2, 62236232 (2017).CrossRefGoogle Scholar
Yu, X. and Robertson, J., Sci. Rep., 6, 37325 (2016).CrossRefGoogle Scholar
Chen, N.-K., Li, X.-B., Wang, X.-P., Xie, S.-Y., Tian, W. Q., Zhang, S., and Sun, H.-B.,IEEE Trans. Nanotechnol., 17, 140146 (2018).CrossRefGoogle Scholar
Momand, J., Wang, R., Boschker, J. E., Verheijen, M. A., Calarco, R., and Kooi, B. J., Nanoscale, 9, 87748780 (2017).CrossRefGoogle Scholar
Lotnyk, A., Hilmi, I., Ross, U., and Rauschenbach, B., Nano Research, 11(3), 16761686 (2018).CrossRefGoogle Scholar