Katarzyna Bejtka1,2,Marco Allione1,Gianluca Milano3,Fabrizio Pirri1,2
Politecnico di Torino1,Istituto Italiano di Tecnologia2,INRiM Istituto Nazionale di Ricerca Metrologica3
Katarzyna Bejtka1,2,Marco Allione1,Gianluca Milano3,Fabrizio Pirri1,2
Politecnico di Torino1,Istituto Italiano di Tecnologia2,INRiM Istituto Nazionale di Ricerca Metrologica3
Ag nanowires (NWs) are of interest among others, for memristive applications, including neuromorphic architecture based on self-assembled nanowire networks [1]. In the device the nanowire undergoes breakdown and then the switching behavior is based on creation and rupture of the filament lying across a gap. The experimental in situ observation of the breakdown behavior and reconfiguration of the filament is of high interest as it could provide better understanding of the switching mechanisms in these nanoobjects.<br/>In this work, we investigate breakdown in single memristive Ag NWs, during voltage sweep stimulation, by in-situ TEM. Joule heating and electromigration are the two possible causes of fracture for metal wires during operation and in-situ observation sheds some more light on its mechanisms [2].<br/>It is also of interest to investigate the temperature influence on the morphology and structure of the single NWs and of small networks of NWs. It was observed that the morphology of single Ag NWs starts changing at around 550 <sup>o</sup>C with observable creation of humps and valleys, which indicate surface roughening. Eventually the NWs break at even higher temperatures. Once the NW undergoes breakdown the change in morphology proceeds following the crystalline orientations of preference. We report on the investigation of local structural and morphological evolution over time as a function of the temperature both for the NWs themselves and within the nanogap appearing after the wire breakdown. We also shed some light on the temperature influence on the morphology of the AgNW junctions within nanowire networks.<br/><br/><b>AKCNOWLEDGMENT</b><br/>Part of this work was supported by the European project MEMQuD, code 20FUN06. This project (EMPIR 20FUN06 MEMQuD) has received funding from the EMPIR programme co-financed by the Participating States and from the European Union’s Horizon 2020 research and innovation programme.<br/><br/><b>REFERENCES</b><br/>G. Milano et al. <i>Adv. Intell. Syst</i>. <b>2</b>, 2000096, 2020.<br/>M. Batra et al. <i>Nanoscale</i> <b>11</b>, 3606, 2019.