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DOE OSTI · 1774124

Phase evolution and amorphous stability upon solid-state reaction in superlattice like Ge–Sb–Te combinatorial thin-film

Hui, Jian·Hu, Qingyun·Luo, Yuxi·Lai, Tianxing·Zhang, Zhan·Ren, Yang·Zhang, Lanting·Wang, Hong
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Abstract

In this paper, the superlattice-like (SLL) Ge–Sb–Te combinatorial thin films were prepared by using a high-throughput ion beam sputtering system. The phase evolution and amorphous stability of such films undergoing heat treatment as a function of the coating sequence and modulation period were systematically studied. The composition structure diagram was constructed via an automated process of data obtained by high-throughput synchrotron micro-X-ray diffraction and lab-based micro-X-ray fluorescence. Furthermore, the element distribution and microstructure in the depth direction of the SLL thin films were characterized with time-of-flight secondary ion mass spectrometry and transmission electron microscopy, respectively. These studies demonstrated that the coating sequence has a significant effect on the element distribution in the as-deposited SLL thin films and the structure of the final product upon solid-state reaction. Reducing the modulation period of the SLL thin film improves the stability of the amorphous Ge–Sb–Te phase. This work lays a solid foundation for the rational design of SLL Ge–Sb–Te thin films to improve their performance.

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37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRYGe-Sb-Teamorphous stabilitycoating materialscombinatorial thin filmselementslayersphase evolutionsuperlattice likethicknessthin films

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Hui, Jian, Hu, Qingyun, Luo, Yuxi, Lai, Tianxing, Zhang, Zhan, Ren, Yang, Zhang, Lanting, Wang, Hong. 2020-12-04. Phase evolution and amorphous stability upon solid-state reaction in superlattice like Ge–Sb–Te combinatorial thin-film. https://doi.org/10.1021/acsaelm.0c00717

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