In this study we were able to experimentally correlate the resistivity change with the vacancy ordering in the GST. For this purpose, the fabrication of a highly ordered single-crystalline material was necessary to facilitate the direct experimental observation of the vacancy layers. We succeeded in fabricating GST with out-of-plane stacking of ordered vacancy layers by means of three distinct methods: Molecular beam epitaxy, thermal annealing and application of femtosecond laser pulses, indication of the fact that the ordering in GST occurs regardless of the fabrication method. By means of x-ray diffraction we assessed the degree of vacancy ordering in the material and directly correlated it with the MIT through low temperature electrical measurements. In addition we have shown that is possible produce GST with different degree of ordering, gaining a large range of resistivity. The latter result might allow the realization of ordered GST based cells with larger programming windows.
T. Siegrist et al., Nat. Mater. 2011, 10, 202
Zhang et al. Nat. Mater. 2012, 11, 952
|1||Author||V. Bragaglia , F. Arciprete , W. Zhang , A. M. Mio , E. Zallo , K. Perumal , A. Giussani , S. Cecchi , J. E. Boschker , H. Riechert , S. Privitera , E. Rimini , R. Mazzarello , R. Calarco|
Metal-insulator transition driven by vacancy ordering in GeSbTe phase change materials
|Source||Sci. Rep. , 6 , 23843 ( 2016 )|
: 10.1038/srep23843 |
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