Application of (MoTe2)xSb1-x thin films with high speed and high stability in phase-change memory

Nanoscale phase change films of (MoTe₂)_xSb_1-x were prepared using magnetron sputtering technique. The investigation focused on the influence of the presence of MoTe₂ on the phase change characteristics of Sb materials as well as the electrical properties of devices. (MoTe₂)_xSb_1-x phase change films showed good thermal stability, especially for (MoTe₂)_0.08Sb_0.92 films. (MoTe₂)_xSb_1-x films had higher phase change temperature (∼185 °C), larger crystallization activation energy (∼4.0 eV), smaller resistance drift index (∼0.03582), and wider band gap (0.629 eV) than pure Sb films, indicating better thermal stability. According to X-Ray Diffraction and Atomic Force Microscope, it could be found that doping MoTe₂ in Sb could inhibit the grain growth and make the surface of Sb film flatter. According to the outcomes stemming from X-ray photoelectron spectroscopy, some bonds involving Mo–Te and Sb–Sb underwent breakage and actively contributed to the formation process of other chemical bonds at the interface. The formation of small Sb₂Te₃ and Sb grains in the as-deposited state played a role in inducing crystallization and accelerating phase transition. The band gap in (MoTe₂)_xSb_1-x films augmented with the increase of MoTe₂ content. The power consumption of the (MoTe₂)_0.08Sb_0.92-based phase-change memory device was considerably reduced compared to GST film and could achieve ultra-fast resistance transition within 10 ns. The results showed that (MoTe₂)_xSb_1-x phase change films have the advantages of high stability, low power consumption, and rapid speed, which is a potential choice for phase change memory.