KINETICS OF EVAPORATION OF BEADED AG FILM ON SAPPHIRE AND ON ALUMINA SCALE

Morphological changes of beaded Ag film on sapphire and on alumina sca le were investigated by means of scanning electron microscopy and Auge r spectroscopy in the temperature range of 822-973 K. It was found tha t the decrease of the effective thickness and the shift of the boundar y of the layer can be attributed to the evaporation of silver into the gas phase. Experimental results were analyzed in terms of the model d eveloped by Kaganovskii and Beke. Our results show that the process is controlled by surface diffusion and temperature dependence of the sur face mass transport coefficients is deduced from the experimental data . (C) 1996 American Institute of Physics.