School of Materials Science and Engineering, University of New South Wales , Sydney, NSW 2052, Australia.
ACS Appl Mater Interfaces. 2018 Jan 24;10(3):2716-2724. doi: 10.1021/acsami.7b16142. Epub 2018 Jan 9.
Silver nanowire (Ag NW) networks have been widely studied because of a great potential in various electronic devices. However, nanowires usually undergo a fragmentation process at elevated temperatures due to the Rayleigh instability that is a result of reduction of surface/interface energy. In this case, the nanowires become completely insulating due to the formation of randomly distributed Ag particles with a large distance and further applications are hindered. Herein, we demonstrate a novel concept based on the combination of ultraviolet/ozone irradiation and a low-temperature annealing process to effectively utilize and control the fragmentation behavior to realize the resistive switching performances. In contrast to the conventional fragmentation, the designed Ag/AgO interface facilitates a unique morphology of short nanorod-like segments or chains of tiny Ag nanoparticles with a very small spacing distance, providing conduction paths for achieving the tunneling process between the isolated fragments under the electric field. On the basis of this specific morphology, the Ag NW network has a tunable resistance and shows volatile threshold switching characteristics with a high selectivity, which is the ON/OFF current ratio in selector devices. Our concept exploits a new function of Ag NW network, i.e., resistive switching, which can be developed by designing a controllable fragmentation.
银纳米线（AgNW）网络由于在各种电子设备中具有巨大的潜力而被广泛研究。然而，由于表面/界面能的减少导致瑞利不稳定性，纳米线通常在高温下经历碎裂过程。在这种情况下，由于形成了具有大距离的随机分布的 Ag 颗粒，纳米线完全变成绝缘的，进一步的应用受到阻碍。在此，我们展示了一种基于结合紫外线/臭氧辐照和低温退火过程的新概念，以有效地利用和控制碎裂行为，实现电阻开关性能。与传统的碎裂相比，设计的 Ag/AgO 界面促进了短纳米棒状段或微小 Ag 纳米颗粒链的独特形态，具有非常小的间隔距离，为在电场下实现隔离碎片之间的隧道过程提供了导电路径。基于这种特定的形态，AgNW 网络具有可调电阻，并表现出具有高选择性的易失性阈值开关特性，即选择器器件中的导通/关断电流比。我们的概念利用了 AgNW 网络的一个新功能，即电阻开关，通过设计可控碎裂可以实现这一功能。
