Investigation of condensation of small portions of Ag at thermal evaporation in vacuum

Abstract

The formation of arrays of Ag nanoparticles from vapor phase on the unheated surface of the amorphous carbon by sequential evaporation of the two portions with decreasing masses has been studied using scanning electron microscopy. The dependence of particle size and their surface density on the amount of evaporated Ag was detected. The precipitate after condensation is in an unstable state: thermal treatment at low temperatures (200-250°C) leads to significant changes and the array goes into a metastable state. This is manifested in the absence of further changes after repeated heat treatment at the same temperature or 100°C higher. It is shown that sequential evaporation of the two portions of the silver with a decrease in mass leads to bimodal distribution of particle sizes in the array.