Characteristics of Sb$_{6}$Te$_{4}$/VO$_{2}$ Multilayer Thin Films for Good Stability and Ultrafast Speed Applied in Phase Change Memory
Yi-Feng Hu1,3,4**, Xuan Guo1, Qing-Qian Qiu2, Tian-Shu Lai2
1School of Mathematics and Physics, Jiangsu University of Technology, Changzhou 213000 2State Key Laboratory of Optoelectronic Materials and Technology, School of Physics, Sun Yat-Sen University, Guangzhou 510275 3State Key Laboratory of Silicon Materials, Zhejiang University, Hangzhou 310027 4Key Laboratory of Microelectronic Devices & Integrated Technology, Institute of Microelectronics, Chinese Academy of Sciences, Beijing 100029
Abstract：The Sb$_{6}$Te$_{4}$/VO$_{2}$ multilayer thin films are prepared by magnetron sputtering and the potential application in phase change memory is investigated in detail. Compared with Sb$_{6}$Te$_{4}$, Sb$_{6}$Te$_{4}$/VO$_{2}$ multilayer composite thin films have higher phase change temperature and crystallization resistance, indicating better thermal stability and less power consumption. Also, Sb$_{6}$Te$_{4}$/VO$_{2}$ has a broader energy band of 1.58 eV and better data retention (125$^{\circ}\!$C for 10 y). The crystallization is suppressed by the multilayer interfaces in Sb$_{6}$Te$_{4}$/VO$_{2}$ thin film with a smaller rms surface roughness for Sb$_{6}$Te$_{4}$/VO$_{2}$ than monolayer Sb$_{4}$Te$_{6}$. The picosecond laser technology is applied to study the phase change speed. A short crystallization time of 5.21 ns is realized for the Sb$_{6}$Te$_{4}$(2 nm)/VO$_{2}$ (8 nm) thin film. The Sb$_{6}$Te$_{4}$/VO$_{2}$ multilayer thin film is a potential and competitive phase change material for its good thermal stability and fast phase change speed.
2018, Vol. 35 
