Self-Limited Growth of Nanocrystals in Structural Heterogeneous Phase-Change Materials during the Heating Process

• DOI: 10.1021/acs.cgd.8b01745
• Publication Date: 2019-01-04T16:00:42Z
• Authors: Guoxiang Wang; Yawen Zhang; Chao Li; Andriy Lotnyk; Yegang Lu; Xiang Shen
• Keywords: Orthorhombic crystal system; Metastability

Typical nanocomposite heterogeneous ZnSb-Al2O3 and ZnSb-ZnO phase-change materials were prepared. A direct comparison of the distinct structures in amorphous, metastable, stable states between two different was investigated systematically. Upon heating, films show a two-step crystallization process with formation metastable orthorhombic ZnSb phase ahead trigonal phase, while could exhibit one-step when ZnO-doping concentration is more than 12.3 atom %. In case ZnSb-Al2O3, structural transition to accompanied by pronounced increase grain size up 100 nm. Such an crystal not found films; i.e., nanocrystals do grow significantly crystallized film precipitated phase. By method advanced scanning transmission electron microscopy, we clearly find that growth limited separated ZnO domain formation, which improves amorphous thermal stability optimized 10-year data retention ability 229.2 °C for (ZnSb)81.8(ZnO)18.2 film.