Download PDFOpen PDF in browserEffects of temperatures on pressure-induced structural changes in amorphous Si: A molecular-dynamics study5 pages•Published: May 14, 2020AbstractThe structural changes of amorphous silicon (a-Si) under compressive pressure were examined by molecular-dynamics simulations using the Tersoff interatomic potential. a-Si prepared by melt-quenching methods was pressurized up to 30 GPa under different temperatures (300K and 500K). The density of a-Si increased from 2.26 to 3.24 g/cm3 with pressure, suggesting the occurrence of the low-density to high-density amorphous phase transformation. This phase transformation occurred at the lower pressure with increasing the temperature because the activation barrier for amorphous-to-amorphous phase transformation could be exceeded by thermal energy. The coordination number increased with pressure and time, and it was saturated at different values depending on the pressure. This suggested the existence of different metastable atomic configurations in a-Si. Atomic pair-distribution functions and bond-angle distribution functions suggested that the short-range ordered structure of high-density a-Si is similar to the structure of the high-pressure phase of crystalline Si (β-tin and Imma structures).Keyphrases: amorphous si, crystalline si, high pressure phase, molecular dynamics study (md), phase transformation In: Tich Thien Truong, Trung Nghia Tran, Quoc Khai Le and Thanh Nha Nguyen (editors). Proceedings of International Symposium on Applied Science 2019, vol 3, pages 118-122.
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