An investigation of the electroforming processes for platinum discontinuous thinfilms is detailed. Current–voltage characteristics, for metal nanoislandsdeposited by sputtering, were obtained in vacuum and air and typically showedvoltage-controlled negative resistance (VCNR) behaviour. The current maximumshifted with the electrode separation. Electroforming under high current densityregimes was non-regenerative as samples showed irreversible resistance changes.SEM examination of the film revealed a change in the metal microstructure. Suchmodifications arise as a result of the current flowing through the film inducingelectro and thermal migration. Current-induced effects were studied by modellingthe metal nanoisland (MN) layer as an array of cubic cells. Plots of currentdistribution showed that hot-spots develop along conductive paths.Electromigration combined with resistive heating can lead to progressivedestruction of current channels at these hot-spots. Hence, current profiles andSEM micrographs were interpreted as evidence of a ‘macroscopic’ electricalbreakdown of sample conduction due to microstructural modifications of the thinfilm. The reduction of ohmic component and consequent resistive heating alongthe current channels prevented the metal migration and stable current profileswere obt
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