Local Heat Dissipation of Ag Nanowire Networks Examined with Scanning Thermal Microscopy

Abstract

Silver nanowires (AgNWs) have shown remarkable potential as materials for transparent conductive electrodes in next-generation flexible devices because of their excellent physical properties. However, despite this advantage, breakdown occurs when AgNWs are exposed to a high temperature and current flow, which has been a significant obstacle. Therefore, a thorough understanding of the breakdown based on local thermal and electrical analyses is essential for developing new devices for various electronic applications. As it is difficult to measure the local heat dissipation occurring at a nanoscale, the breakdown process has not yet been analyzed in detail through an experimental approach. In this study, the local breakdown process due to Joule heat and concentrated current density was examined using scanning thermal microscopy when current flowed through a AgNW network. The results showed that the nanowire breaks at ∼453 K, which is lower than the previously reported temperature of breakdown that occurred only via environmental heating. In this study, we found that the AgNW network can be broken down at temperatures below ∼500 K because the atomic flux due to the combined effects of Rayleigh instability and electromigration is applied to atoms on the surface when the nanowires operate electrically. This work proposes that electromigration and Rayleigh instability should be considered in the design of AgNW devices.

Thermo-electro-optical properties of seamless metallic nanowire networks for transparent conductor applications

“…For this reason, accurately accessing the localized temperature distribution of individual nanowire channels experimentally can be extremely difficult at nanometer resolution. 64,70,71,73,74 Zeng et al 64 have studied the electrothermal properties of nanoscale systems by simulating the local current density and temperature distributions in Ag continuous nano-crack networks. They observed significant internal temperature differences throughout the material template that can lead to junction breakdown due to thermalassisted electronic migration mechanisms occurring in the network.…”

“…Seamless networks of nano-cracks have been extensively studied experimentally. 64,70,[73][74][75][76][77][78][79] However, theoretical and computational advancements in this field are limited due to various computational challenges such as exploring a vast parameter phase space, designing and integrating the device with other circuit components, customizing raw materials for specific target applications, and modelling the coupling of distinct physical responses. 64,80,81 In this manuscript, we report an in-depth computational analysis of the thermo-electro-optical properties of templatebased metallic networks with seamless junctions made of different materials including Ag, Au, Al, and Cu.…”

“…13) are sensitive to material and network layout, and our numbers are within the same orders of magnitude as other reports in the literature. 64,[68][69][70]72,73,94,[119][120][121] The contact thermal conductance between the NWN and the substrate is an additional factor addressed in this work that influences the temperature profile distribution inside the metallic seamless NWNs and, subsequently, the sheet resistance. In nanodevices, the contact/interfacial thermal resistance (inverse of contact thermal conductance) plays a major part in the transfer of thermal energy.…”

“…Seamless networks of nano-cracks have been extensively studied experimentally. 64,70,73–79 However, theoretical and computational advancements in this field are limited due to various computational challenges such as exploring a vast parameter phase space, designing and integrating the device with other circuit components, customizing raw materials for specific target applications, and modelling the coupling of distinct physical responses. 64,80,81…”

Resistive Switching of Self‐Assembled Silver Nanowire Networks Governed by Environmental Conditions

“…[28,33,45] However, excessive currents may affect the percolation because of electromigration and the local melting of either the AgNWs or the metallic filaments that are thought to form across the junctions. [46,47] On the other hand, the Ag-PVP-Ag junctions might be the playground for the occurrence of electrochemical processes. For example, Ag + ions remaining from the synthesis, or produced by ambient oxidation of the AgNWs, can act as a charge carriers diffusing through the PVP layer upon the application of an external voltage.…”