Dependence of the longitudinal strain coefficient of resistivity of silver films on thickness and grain size diameter

A grain boundary model modified by including the Fuchs size effect has been used to derive a general expression for the longitudinal strain coefficient of resistivity of continuous polycrystalline silver films, of thickness greater than the intrinsic mean free path, in terms of the grain size diameter and the film thickness. It has been found that the longitudinal strain coefficient of film resistivity has zero value for very small grain size and attains the bulk value when the grain size and the film thickness are very large. It has also been found that a threshold value of the grain size diameter exists, below which the film thickness has practically no effect on the strain coefficient of film resistivity. However, for grain size diameters greater than the threshold value, thicker films have values of the strain coefficient or resistivity higher than those for thinner films.