TY - JOUR
T1 - Tuning the Crystallization Mechanism by Composition Vacancy in Phase Change Materials
AU - Song, Wen Xiong
AU - Tang, Qiongyan
AU - Zhao, Jin
AU - Veron, Muriel
AU - Zhou, Xilin
AU - Zheng, Yonghui
AU - Cai, Daolin
AU - Cheng, Yan
AU - Xin, Tianjiao
AU - Liu, Zhi Pan
AU - Song, Zhitang
N1 - Publisher Copyright:
© 2024 American Chemical Society
PY - 2024/3/27
Y1 - 2024/3/27
N2 - Interface-influenced crystallization is crucial to understanding the nucleation- and growth-dominated crystallization mechanisms in phase-change materials (PCMs), but little is known. Here, we find that composition vacancy can reduce the interface energy by decreasing the coordinate number (CN) at the interface. Compared to growth-dominated GeTe, nucleation-dominated Ge2Sb2Te5 (GST) exhibits composition vacancies in the (111) interface to saturate or stabilize the Te-terminated plane. Together, the experimental and computational results provide evidence that GST prefers (111) with reduced CN. Furthermore, the (8 - n) bonding rule, rather than CN6, in the nuclei of both GeTe and GST results in lower interface energy, allowing crystallization to be observed at the simulation time in general PCMs. In comparison to GeTe, the reduced CN in the GST nuclei further decreases the interface energy, promoting faster nucleation. Our findings provide an approach to designing ultrafast phase-change memory through vacancy-stabilized interfaces.
AB - Interface-influenced crystallization is crucial to understanding the nucleation- and growth-dominated crystallization mechanisms in phase-change materials (PCMs), but little is known. Here, we find that composition vacancy can reduce the interface energy by decreasing the coordinate number (CN) at the interface. Compared to growth-dominated GeTe, nucleation-dominated Ge2Sb2Te5 (GST) exhibits composition vacancies in the (111) interface to saturate or stabilize the Te-terminated plane. Together, the experimental and computational results provide evidence that GST prefers (111) with reduced CN. Furthermore, the (8 - n) bonding rule, rather than CN6, in the nuclei of both GeTe and GST results in lower interface energy, allowing crystallization to be observed at the simulation time in general PCMs. In comparison to GeTe, the reduced CN in the GST nuclei further decreases the interface energy, promoting faster nucleation. Our findings provide an approach to designing ultrafast phase-change memory through vacancy-stabilized interfaces.
KW - Te-terminated boundary
KW - crystallization mechanism
KW - interface-influenced crystallization
KW - interface-influenced grain size
KW - phase change material
KW - vacancy-stabilized interface
UR - https://www.scopus.com/pages/publications/85188142890
U2 - 10.1021/acsami.3c18538
DO - 10.1021/acsami.3c18538
M3 - 文章
C2 - 38498850
AN - SCOPUS:85188142890
SN - 1944-8244
VL - 16
SP - 15023
EP - 15031
JO - ACS Applied Materials and Interfaces
JF - ACS Applied Materials and Interfaces
IS - 12
ER -