Fast crystallization of Mg-doped Sb4Te for phase change memory

• Mg19.8(Sb4Te)80.2 exhibits a better thermal stability compared with Ge2Sb2Te5.
• Mg19.8(Sb4Te)80.2 exhibits a better data retention ability at 113.6 °C for ten years.
• Mg19.8(Sb4Te)80.2 exhibits fast crystallization speed 20 ns at a laser power of 60 mW.

We prepared Mg-doped Sb4Te films and investigated their structural, electrical and optical properties. It was found that Mg could increase the crystallization temperature and improve the activation energy of crystallization as well as amorphous state stability of the Sb4Te film. Compared with Ge2Sb2Te5, the optimal composition of Mg19.8(Sb4Te)80.2 exhibits a higher crystallization temperature (∼187 °C), and better data retention ability (keeping the amorphous state at 113.6 °C for ten years). Moreover, fast full crystallization (∼20 ns at a laser power of ∼60 mW) in the Mg19.8(Sb4Te)80.2 film is confirmed, which is essential to achieve rapid data recording in phase change memory.