Resistance Drift Convergence and Inversion in Amorphous Phase Change Materials
Resistance Drift Convergence and Inversion in Amorphous Phase Change Materials
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DOI：
10.1002/adfm.202207194
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发表时间：
2022-09-25
影响因子：
19
通讯作者：
Wuttig, Matthias
中科院分区：
文献类型：
--
作者：
Pries, Julian;Stenz, Christian;Wuttig, Matthias
相变材料（PCM）是人工智能技术发展的关键，如高密度存储器和神经形态计算，这要归功于它们通过逐步电阻编码进行多级数据存储的能力。通过调整存储单元的结晶和非晶体积分数来实现各个电阻水平。然而，非晶相表现出电阻随时间的漂移，这迄今为止阻碍了多级存储方案的商业实现。在这项研究中，基本的物理过程中的电阻漂移与建模的目标阐明，这将有助于最大限度地减少和潜在地克服PCM存储器设备中的漂移。提供了明确的证据表明，电阻漂移是由玻璃动力学。实验证明了非晶硫属化物Ge_（15）Te_（85）和相变材料Ge_（3Sb6）Te_（5）的电阻率收敛和漂移反转，并成功地用玻璃动力学模型预测了这些变化。这种对电阻漂移过程的新见解为先进PCM器件的开发提供了工具。
Phase change materials (PCMs) are key to the development of artificial intelligence technologies such as high-density memories and neuromorphic computing, thanks to their ability for multi-level data storage through stepwise resistive encoding. Individual resistance levels are realized by adjusting the crystalline and amorphous volume fraction of the memory cell. However, the amorphous phase exhibits a drift in resistance over time that has so far hindered the commercial implementation of multi-level storage schemes. In this study, the underlying physical process of resistance drift with the goal of modeling is elucidated that will help minimize and potentially overcome drift in PCM memory devices. Clear evidence is provided that the resistance drift is dominated by glass dynamics. Resistivity convergence and drift inversion for the amorphous chalcogenide Ge15Te85 and the PCM Ge3Sb6Te5 are experimentally demonstrated and these changes are successfully predicted with a glass dynamics model. This new insight into the resistance drift process provides tools for the development of advanced PCM devices.