Si _xSb ₂Te materials with stable phase for phase change random access memory applications

The physical and electrical properties of Si _xSb ₂Te system materials with various Si contents have been systemically studied with the aim of finding the most suitable composition for the phase change random access memory (PCRAM) applications. Si _xSb ₂Te shows better thermal stability than Ge ₂Sb ₂Te ₅ due to no Te separation under high annealing temperatures. The increase of Si content can enhance the data retention ability of Si _xSb ₂Te materials. When the value of x is larger than 0.44, the 10-year data retention temperature for Si _xSb ₂Te will exceed 110 ° C, which meets the long-term data retention requirement. Furthermore, Si-rich Si _xSb ₂Te materials exhibit the improvement on thickness change after annealing compared with Ge ₂Sb ₂Te ₅. In addition, the PCRAM devices based on Si _xSb ₂Te (x = 0.31, 0.44) were fabricated and the electrical operations were carried out. Both of them show the outstanding performances with long-term operations.