Origin of resistivity contrast in interfacial phase-change memory: The crucial role of Ge/Sb intermixing
Origin of resistivity contrast in interfacial phase-change memory: The crucial role of Ge/Sb intermixing
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DOI：
10.1063/1.5088068
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发表时间：
2019-04-01
影响因子：
4
通讯作者：
Robertson, John
中科院分区：
文献类型：
--
作者：
Saito, Yuta;Kolobov, Alexander V.;Robertson, John
基于GeTe-Sb_2 Te_3赝二元合金可逆非晶-晶相变的相变存储器是最有前途的非易失性存储技术之一。最近提出的基于超晶格的存储器或界面相变存储器（iPCM）的特征在于显著更快的切换、更低的能耗和更好的耐久性。iPCM中的开关机制，其中SET和SET状态都是结晶的，仍然有争议。在这里，使用从头算密度泛函理论模拟，一个概念上新的开关机制iPCM的推导，这是基于带隙的潜在景观的变化，与本地偏离整个货车德瓦耳斯间隙的赝二元化学计量和费米能级的相关位移。在这个过程中的关键作用属于Ge/Sb混合的阳离子平面上的iPCM。这些发现提供了一个全面的了解在iPCM的开关机制，是一个重要的一步，有见地的相变存储器技术的发展。由AIP Publishing授权出版。
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. Published under license by AIP Publishing.