Chalcogenide materials play essential roles in modern nonvolatile memory technology in the form of both phase‐change memory (PCM) and selector devices. Herein, Bi–Te binary alloys are explored as an alternative candidate for superlattice (SL) or interfacial PCM (iPCM). GeTe/Bi₄Te₃ (GT/BT) SL exhibits similar structural features to conventional GeTe/Sb₂Te₃ (GT/ST) SL, such as highly oriented crystal grains and intermixing. Furthermore, preliminary device measurements show that Ge–Bi–Te (GBT) SL switches in a similar manner to conventional Ge–Sb–Te (GST), suggesting that they may be a promising candidate for memory applications. In addition, Bi₂Te₃/Sb₂Te₃ (BT/ST) heterostructure films have been successfully fabricated and show clear interface stacking at the atomic level. Although the BT/ST heterostructure is ostensibly a p–n junction, rectifying behavior is not observed in current (I)–voltage (V) measurements due to the existence of a large number of carriers in both layers. Finally, density functional theory (DFT)‐based simulations suggest that an ideal BT/ST heterostructure may possess intriguing topological properties that can enable novel functional devices. The Bi–Te binary alloys offer promising potential for optimizing PCM performance as well as for the realization of novel functional electronic devices.

中文翻译：

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用于相变存储器和未来电子应用的硫族化物材料工程：从Sb–Te到Bi–Te

硫族化物材料在现代非易失性存储技术中以相变存储器（PCM）和选择器器件的形式发挥着至关重要的作用。在本文中，Bi-Te二元合金被用作超晶格（SL）或界面PCM（iPCM）的替代候选材料。GeTe / Bi ₄ Te ₃（GT / BT）SL具有与常规GeTe / Sb ₂ Te ₃（GT / ST）SL相似的结构特征，例如高度取向的晶粒和相互混合。此外，初步的器件测量表明，Ge-Bi-Te（GBT）SL的开关方式与传统的Ge-Sb-Te（GST）类似，这表明它们可能是存储器应用的有前途的候选者。另外，Bi ₂ Te ₃ / Sb ₂ Te₃（BT / ST）异质结构薄膜已成功制备，并在原子水平上显示出清晰的界面堆叠。尽管BT / ST异质结构表面上是ap-n结，但由于两层中都存在大量载流子，因此在电流（I）-电压（V）测量中未观察到整流行为。最后，基于密度泛函理论（DFT）的模拟表明，理想的BT / ST异质结构可能具有吸引人的拓扑特性，可以启用新型功能器件。Bi-Te二元合金为优化PCM性能以及实现新型功能性电子设备提供了有希望的潜力。