Study on the modulation of sb phase change thin films and device properties by MoTe₂ heterojunction layer

In this study, MoTe₂/Sb heterojunction films were fabricated through alternating deposition of MoTe₂ and Sb materials, and their properties were thoroughly examined. When compared to single-layer Sb films, the MoTe₂/Sb heterojunction films exhibited a higher crystallization temperature (∼ 180.5 °C), an improved 10-year data retention temperature (∼ 97.41 °C), and a greater crystallization activation energy (∼ 2.81 ± 0.16 eV), indicating superior thermal stability. Near-infrared spectrophotometry revealed that the band gap of the crystalline MoTe₂/Sb heterojunction films was wider than that of Sb films. Furthermore, X-ray diffractometer analysis demonstrated that the MoTe₂ layer inhibited grain growth in Sb, resulting in smaller grain sizes. Atomic force microscopy observations revealed that the surface of MoTe₂/Sb heterojunction films was smoother than that of single-layer Sb films. Phase change memory devices utilizing MoTe₂/Sb heterojunction films demonstrated the reversible SET-RESET conversion across various pulse widths with lower operating power consumption compared to single-layer Sb films. These results demonstrate that the properties of Sb films can be effectively modulated through the MoTe₂ heterojunction, yielding phase change materials with exceptional overall performance.