Morphological instabilities of silver nanowires induced by electric current injection

Abstract

Over the past decade, transparent conducting materials (TCMs) have been extensively studied for their application in devices such as heaters, solar cells, light-emitting diodes, and smart windows. These devices often rely on transparent electrodes based on indium tin oxide (ITO). Although ITO offers good transparency and electrical conductivity, it suffers from several drawbacks, including brittleness and the scarcity of indium. Silver nanowire (AgNW) networks have thus emerged as a promising alternative to ITO based materials, due to their excellent electrical conductivity, high optical transparency, mechanical flexibility, and compatibility with low-cost fabrication processes.

As a result of these advantageous properties, AgNW networks are exposed to various types of stress. This work specifically investigates morphological instabilities induced by electrical stress, revealing both localized failures in individual nanowires and large-scale breakdown regions. The respective contributions of electromigration and the Joule effect are analyzed to better understand the behavior of the network under electrical stress. Moreover, the maximum current density that a nanowire can sustain is evaluated to determine the critical threshold leading to morphological instabilities. Finally, a digital twin approach is employed to further explore and illustrate the behavior of AgNW networks under electrical stress.