High thermal stability and low power dissipation PCM with nanoscale oxygen-doped SS thin film

Abstract

To improve thermal stability and reduce power dissipation of phase-change memory (PCM), the oxygen-doped Sn₁₅Sb₈₅ (SS) thin film is proposed by magnetron sputtering in this study. Comparing to undoped Sn15Sb85(SS), the oxygen-doped-SS thin film has superior thermal stability and better data retention. Meanwhile, the electrical conductivity of crystallisation oxygen-doped-SS thin film is also lower than that of SS, which means its less power consuming in PCM. The electrical conductivity ratio between amorphous and crystalline states for oxygen-doped SS reaches up to two orders of magnitude. After oxygen doping, the root-mean-square surface roughness from amorphous (0.29 nm) to crystalline (0.46 nm) state for oxygen-doped-SS thin films becomes smaller. The switching time of amorphisation process for the oxygen-doped-SS thin film (∼2.07 ns) is shorter than Ge₂Sb₂Te₅ (GST) (∼3.05 ns). X-ray diffractometer is recorded to investigate the change of crystalline structure. Thus, the authors infer that oxygen-doped SS is a promising phase-change thin film for PCM.