Ran Ke, Jo Janghyun, Cruces Sofía, Wang Zhenxing, Dunin-Borkowski Rafal E, Mayer Joachim, Lemme Max C
Advanced Microelectronic Center Aachen, AMO GmbH, Aachen, Germany.
Central Facility for Electron Microscopy GFE, RWTH Aachen University, Aachen, Germany.
Nat Commun. 2025 Aug 12;16(1):7433. doi: 10.1038/s41467-025-62592-2.
Advanced operando transmission electron microscopy (TEM) techniques enable the observation of nanoscale phenomena in electronic devices during operation. Here, we investigated lateral memristive devices composed of two dimensional layered MoS with Pd and Ag electrodes. Under external bias voltage, we visualized the formation and migration of Ag conductive filaments (CFs) between the two electrodes, and their complete dissolution upon reversing the biasing polarity. The CFs exhibited a wide range of sizes, from several Ångströms to tens of nanometers, and followed diverse pathways: along the MoS surfaces, within the van der Waals gap between MoS layers, and through the spacing between MoS bundles. Our method enables correlation between current-voltage responses and real-time TEM imaging, offering insights into failed and anomalous switching behaviors, and clarifying the cycle-to-cycle variabilities. Our findings provide solid evidence for the electrochemical metallization mechanism, elucidate the formation dynamics of CFs, and reveal key parameters influencing the switching performance.
先进的原位透射电子显微镜（TEM）技术能够在电子器件运行过程中观察纳米级现象。在此，我们研究了由二维层状MoS与Pd和Ag电极组成的横向忆阻器件。在外部偏置电压下，我们可视化了两个电极之间Ag导电细丝（CFs）的形成和迁移，以及在反转偏置极性时它们的完全溶解。CFs呈现出从几埃到几十纳米的广泛尺寸范围，并遵循多种路径：沿着MoS表面、在MoS层之间的范德华间隙内以及穿过MoS束之间的间距。我们的方法能够实现电流-电压响应与实时TEM成像之间的关联，深入了解故障和异常开关行为，并阐明逐周期变化情况。我们的研究结果为电化学金属化机制提供了确凿证据，阐明了CFs的形成动力学，并揭示了影响开关性能的关键参数。
