Measurement of intrinsic stress in silver films by using ellipsometry

Abstract
Annealing of silver films in the temperature range 30–300 °C is found to result in the minimization of stress in the films which, in turn, affects the hillock growth on the film surface. This variation in hillock growth is studied by using ellipsometry. It is found that the numerical value of the thermal stress in the film is approximately equal to that of the intrinsic stress when the hillock growth is retarded. The intrinsic stress in silver films is calculated by using this technique for different film thicknesses. The values of the film thicknesses are so selected that the difference between them is quite large. The results obtained in the present work are found to be in fairly good agreement with those obtained by earlier workers.