Phase change abilities of SiO 2 doped Sb 2 Te 3 phase change materials were systemically studied. Compared to pure Sb 2 Te 3 , crystallization temperature ( T C ) is increased obviously (153°C), and phase change characteristics are remarkably improved.SiO 2 doping will not cause oxidization of Sb and Te elements. The grain size of Sb 2 Te 3 is restrained remarkably by amorphous SiO 2 . The average diameter of the Sb 2 Te 3 particles is about 10 nm. The Set and Reset voltages for SiO 2 -Sb 2 Te 3 based PCM cell are much lower than those of Ge 2 Sb 2 Te 5 based PCM cell. Meanwhile, PCM cell using this material shows good endurance with cycles up to 3.5 × 10 6 .