THE AGING OF EVAPORATED SILVER FILMS

Abstract

The spontaneous aging of thin films of silver was studied by following electrical resistance variations with time immediately after deposition in vacuo. In one series of experiments films, all deposited in a fixed time of 100 seconds and with initial resistances from 170,000 Ω to 20 Ω, were investigated. The resistance of some films rose rapidly with time; in others it dropped rapidly, and in still others resistance changes were less pronounced. In a second series eight films were formed, all with equal initial resistances (5000 Ω) but deposited in different times. The rate of decrease in resistance was greater as the rate of deposition increased. The limiting value of resistance depended on the time of deposition. A possible qualitative explanation of the results on the basis of distortion decay and film aggregation is proposed.