TY - JOUR
T1 - Origin of resistivity contrast in interfacial phase-change memory
T2 - The crucial role of Ge/Sb intermixing
AU - Saito, Yuta
AU - Kolobov, Alexander V.
AU - Fons, Paul
AU - Mitrofanov, Kirill V.
AU - Makino, Kotaro
AU - Tominaga, Junji
AU - Robertson, John
N1 - Funding Information:
This study was supported by JST CREST No. JPMJCR14F1 and KAKENHI JP16K04896 and 18K14306.
Publisher Copyright:
© 2019 Author(s).
PY - 2019/4/1
Y1 - 2019/4/1
N2 - Phase-change memories based on reversible amorphous-crystal transformations in pseudobinary GeTe-Sb2Te3 alloys are one of the most promising nonvolatile memory technologies. The recently proposed superlattice-based memory, or interfacial phase-change memory (iPCM), is characterized by significantly faster switching, lower energy consumption, and better endurance. The switching mechanism in iPCM, where both the SET and RESET states are crystalline, is still contentious. Here, using the ab initio density functional theory simulations, a conceptually new switching mechanism for iPCM is derived, which is based on the change in the potential landscape of the bandgap, associated with local deviations from the pseudobinary stoichiometry across the van der Waals gaps and the associated shift of the Fermi level. The crucial role in this process belongs to Ge/Sb intermixing on the cation planes of iPCM. These findings offer a comprehensive understanding of the switching mechanisms in iPCM and are an essential step forward to the insightful development of phase-change memory technology.
AB - Phase-change memories based on reversible amorphous-crystal transformations in pseudobinary GeTe-Sb2Te3 alloys are one of the most promising nonvolatile memory technologies. The recently proposed superlattice-based memory, or interfacial phase-change memory (iPCM), is characterized by significantly faster switching, lower energy consumption, and better endurance. The switching mechanism in iPCM, where both the SET and RESET states are crystalline, is still contentious. Here, using the ab initio density functional theory simulations, a conceptually new switching mechanism for iPCM is derived, which is based on the change in the potential landscape of the bandgap, associated with local deviations from the pseudobinary stoichiometry across the van der Waals gaps and the associated shift of the Fermi level. The crucial role in this process belongs to Ge/Sb intermixing on the cation planes of iPCM. These findings offer a comprehensive understanding of the switching mechanisms in iPCM and are an essential step forward to the insightful development of phase-change memory technology.
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U2 - 10.1063/1.5088068
DO - 10.1063/1.5088068
M3 - Article
AN - SCOPUS:85063728385
SN - 0003-6951
VL - 114
JO - Applied Physics Letters
JF - Applied Physics Letters
IS - 13
M1 - 132102
ER -
