The contradictory nature of increasing the crystallization speed while extending the amorphous stability for phase-change materials (PCMs) has long been the bottleneck in pursuing ultrafast yet persistent phase-change random-access memory. Scandium antimony telluride alloy (Sc_xSb₂Te₃) represents a feasible route to resolve this issue, as it allows a subnanosecond SET speed but years of reliable retention of the RESET state. To achieve the best device performances, the optimal composition and its underlying working mechanism need to be unraveled. Here, by tuning the doping dose of Sc, we demonstrate that Sc_0.3Sb₂Te₃ has the fastest crystallization speed and fairly improved data nonvolatility. The simultaneous improvement in such ‘conflicting’ features stems from reconciling two dynamics factors. First, promoting heterogeneous nucleation at elevated temperatures requires a higher Sc dose to stabilize more precursors, which also helps suppress atomic diffusion near ambient temperatures to ensure a rather stable amorphous phase. Second, however, enlarging the kinetic contrast through a fragile-to-strong crossover in the supercooled liquid regime should require a moderate Sc content; otherwise, the atomic mobility for crystal growth at elevated temperatures will be considerably suppressed. Our work thus reveals the recipe by tailoring the crystallization kinetics to design superior PCMs for the development of high-performance phase-change working memory technology.

长期以来，追求超快而持久的相变随机存取存储器一直是瓶颈，在增加结晶速度的同时扩展相变材料（PCM）的非晶稳定性的矛盾性质。tell碲化锑锑合金（Sc _x Sb ₂ Te ₃）代表了解决此问题的可行途径，因为它可以实现亚纳秒的SET速度，并且可以可靠地保持RESET状态多年。为了获得最佳的设备性能，需要阐明最佳的组成及其潜在的工作机制。在这里，通过调整Sc的掺杂剂量，我们证明了Sc _0.3 Sb ₂ Te ₃具有最快的结晶速度和相当大的数据非易失性。这种“冲突”特征的同时改进源于协调两个动力学因素。首先，在高温下促进异相成核需要更高的Sc剂量来稳定更多的前驱物，这也有助于抑制原子在环境温度附近扩散，以确保相当稳定的非晶相。第二，然而，通过在过冷液体状态下从脆弱到强烈的交叉来扩大动力学对比，应该需要适度的Sc含量；否则，将大大抑制在高温下晶体生长的原子迁移率。