SnSb4/SiO2 multilayered thin films for phase change memory applications

• SnSb4/SiO2 multilayer thin films were prepared in this paper.
• The thermal stability of SnSb4 thin film increased after compositing with SiO2 layer.
• A lower thermal conductivity was obtained for SnSb4/SiO2 multilayer thin film.
• A lower reset power was achieved for SnSb4/SiO2 multilayer thin film.

SnSb4/SiO2 (SS/SiO2) multilayer thin films were prepared by using a radio-frequency (RF) magnetron sputtering method. The amorphous-to-crystalline transitions of SS/SiO2 films were investigated by in situ film resistance measurements. The thermal stability of amorphous SS thin films was greatly improved by the addition of SiO2. However, the thermal conductivity of SS/SiO2 multilayer thin films (0.23 W/(m·K)) was much lower than that of monolayer SS thin film (1.37 W/(m·K)). The result of X-ray diffractomer (XRD) measurement indicated that excess Sb composition existed in SS/SiO2 multilayer thin films, which could accelerate the phase change of the material. The multilayer configuration of SS/SiO2 multilayer thin film before and after crystallization was confirmed by transmission electron microscopy (TEM). Phase change memory (PCM) devices based on [SS(2 nm)/SiO2(1.5 nm)]14 thin film were fabricated and the low power consumption for the RESET operation was achieved (7.8 × 10− 12 J), which was significantly lower than that of GST cell (2.6 × 10− 9 J).