Unique interface-driven crystallization mechanism and element-resolved structure imaging of ZnO-Ge2Sb2Te5 nanocomposites

作者：Wang, Guoxiang; Wang, Hui; Lotnyk, Andriy; Wang, Rongping^*; Shen, Xiang^*

来源：Ceramics International, 2018, 44(18): 22497-22503.

DOI：10.1016/j.ceramint.2018.09.020

• Films
• Grain growth
• Electron microscopy
• Structural applications

Amorphous Ge2Sb2Te5 thin films doped with ZnO were prepared and their crystallization behaviors were investigated. Our results showed that thermal annealing of amorphous ZnO-Ge2Sb2Te5 nanocomposites produced face centered-cubic Ge2Sb2Te5-nanocrystals embedded between interfaces. An increase in crystallization temperature and electrical resistance ratio were attributed to the increase of specific interfacial energies and in homogeneous strain at the oxide/Ge2Sb2Te5 interfaces. The formation of the interfaces not only accelerated crystallization, but also limited the grain growth due to the one-dimensional growth mode. We proposed a crystallization model to elucidate the derived kinetic mechanism of the nanocrystal growth in the Ge2Sb2Te5 matrix. These experimental observations suggest that ZnO-Ge2Sb2Te5 nanocomposites are a good candidate for the applications in phase change memory.

• 出版日期2018-12-15
• 单位宁波大学