Alleviating the trade-off between thermal stability and fast switching in Ru-doped Sb3Te phase change films

Phase change memory is a promising candidate for next-generation nonvolatile memory. Improving the amorphous thermal stability of phase-change materials usually comes at the expense of crystallization speed, because suppressing nucleation tends to slow phase transition kinetics. Here, we show that Ru doping in Sb3Te films can significantly enhance thermal stability while preserving fast switching speed. Structural analyses indicate that Ru disrupts the long-range order of the crystalline phase, which improves amorphous stability. Meanwhile, transmission electron microscopy demonstrates that although long-range order is perturbed, the crystal grains largely retain an ordered internal structure with only slight orientational adjustment, minimizing the negative impact on crystal growth. This structural characteristic alleviates the trade-off between thermal stability and crystallization speed, enabling Ru-doped Sb3Te to achieve both improved data retention and rapid switching speed. These findings provide a practical strategy for designing high-performance phase change materials for embedded memory applications.