A comparison of the Ge-Sb-Te and Si-Sb-Te film oxidization at atmosphere

New phase change materials development has become one of the most critical modules in the fabrication of low power consumption and good data retention phase change memory (PCM). Among various candidates of new phase change materials, SiSbTe (SST) is one of the most promising materials due to its benefits of low RESET current, high crystallization temperature, good adhesion and small volume shrinkage during phase change from amorphous to crystalline state. However, the oxidization of SST film was found when exposing to the atmosphere. By analyzing the depth profile of chemical states, we found oxygen more easily penetrated into the SST film and bonded with Si and Sb compared to GeSbTe (GST) film. The oxidization mechanism between SST and GST was briefly discussed. We achieved 80% improvement of oxidization issue by nitrogen and argon surface treatment. We proposed a manufacturing solution of SST for PCM.