Short-range order in semiconductor alloys: does it exist or matter?

ORAL

Abstract

Chemical short-range order (SRO) in alloys refers to a statistical deviation from a random distribution of atoms in lattice within a short atomic distance. Although SRO has been linked to important properties in metallic alloys and ceramics, its existence and relevance in semiconductor alloys have remained virtually unknown. In early studies we predicted SRO in group IV semiconductor alloys and the induced significant change in electronic and topological properties. Through synergistic efforts combining advanced characterization including 4D-STEM, APT, and EXAFS and our recently developed machine-learning potential, we have explicitly demonstrated the existence and relevance of SRO in group IV alloys. Extending our theoretical development to III-nitrides alloys, we find atomic ordering carries a contrasting form but significantly impacts piezoelectric and ferroelectric properties. The substantial change in properties thus calls for the need for investigating potential routes for controlling SRO to harness novel properties via SRO engineering.

*This work was supported as part of the μ-ATOMS, an Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science, Basic Energy Sciences under Award No. DE-SC0023412.

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Publication: (1) Cao, B.; Chen, S.; Jin, X.; Liu, J.; Li, T. Short-Range Order in GeSn Alloy. ACS Appl. Mater. Interfaces 2020, 12, 57245–57253. https://doi.org/10.1021/acsami.0c18483.
(2) Jin, X.; Chen, S.; Li, T. Coexistence of Two Types of Short-Range Order in Si–Ge–Sn Medium-Entropy Alloys. Commun Mater 2022, 3 (1), 66. https://doi.org/10.1038/s43246-022-00289-5.
(3) Liang, Y.; Chen, S.; Jin, X.; West, D.; Yu, S.-Q.; Li, T.; Zhang, S. Group IV Topological Quantum Alloy and the Role of Short-Range Order: The Case of Ge-Rich Ge1–XPbx. npj Comput. Mater. 2024, 10 (1), 82. https://doi.org/10.1038/s41524-024-01271-0.
(4) Chen, S.; Jin, X.; Zhao, W.; Li, T. Intricate Short-Range Order in GeSn Alloys Revealed by Atomistic Simulations with Highly Accurate and Efficient Machine-Learning Potentials. Phys. Rev. Mater. 2024, 8 (4), 043805. https://doi.org/10.1103/physrevmaterials.8.043805.
(5) Liu, S.; et al. Atomistic short-range order in SiGeSn alloys, under review, https://doi.org/10.21203/rs.3.rs-4909892/v1
(6) Vogl, L,; et al. Identification of short-range order motifs, under review.

Presenters

  • Tianshu Li

    • George Washington University

Authors

  • Tianshu Li

    • George Washington University

  • Shunda Chen

    • George Washington University

  • Xiaochen Jin

    • George Washington University

  • Lilian Vogl

    • University of California, Berkeley

  • Andrew M Minor

    • University of California, Berkeley

  • Shang Liu

    • Dartmouth College

  • Jifeng Liu

    • Dartmouth College