TY - JOUR
T1 - Local-field method for resistivity and electromigration in metallic microstructures
T2 - Application to thin films
AU - Chu, Chon-Saar
AU - Sorbello, R. S.
PY - 1988/1/1
Y1 - 1988/1/1
N2 - A local-field method is described for determining the microscopic potential, the electrical resistivity, and the electromigration driving force on an impurity in a metallic microstructure. The method is an extension of Landauers picture of residual-resistivity dipoles to microstructures, with greater emphasis placed upon the details of the quantum-mechanical scattering process. Using a microscopic, surface-impurity model for surface roughness, we apply the method to a metallic thin film. When the film thickness is smaller than the mean free path, the surface resistivity is found to have oscillatory behavior as a function of film thickness. The form of the oscillations depends upon multiple scattering between the surface impurity and the film surfaces. In thicker films, the Fuchs-Sondheimer result is recovered. The local potential set up by impurity scattering is dipolar in the near- and far-field regions. However, unlike the case of residual-resistivity dipoles in bulk, the effective dipole strength is generally different in the two regions. It is found that the residual-resistivity dipole field decays less rapidly with distance in a thin film than in bulk, thus resulting in a larger voltage drop across an impurity in a thin film. This field enhancement is expected in low-dimensional systems.
AB - A local-field method is described for determining the microscopic potential, the electrical resistivity, and the electromigration driving force on an impurity in a metallic microstructure. The method is an extension of Landauers picture of residual-resistivity dipoles to microstructures, with greater emphasis placed upon the details of the quantum-mechanical scattering process. Using a microscopic, surface-impurity model for surface roughness, we apply the method to a metallic thin film. When the film thickness is smaller than the mean free path, the surface resistivity is found to have oscillatory behavior as a function of film thickness. The form of the oscillations depends upon multiple scattering between the surface impurity and the film surfaces. In thicker films, the Fuchs-Sondheimer result is recovered. The local potential set up by impurity scattering is dipolar in the near- and far-field regions. However, unlike the case of residual-resistivity dipoles in bulk, the effective dipole strength is generally different in the two regions. It is found that the residual-resistivity dipole field decays less rapidly with distance in a thin film than in bulk, thus resulting in a larger voltage drop across an impurity in a thin film. This field enhancement is expected in low-dimensional systems.
UR - http://www.scopus.com/inward/record.url?scp=0001403015&partnerID=8YFLogxK
U2 - 10.1103/PhysRevB.38.7260
DO - 10.1103/PhysRevB.38.7260
M3 - Article
AN - SCOPUS:0001403015
VL - 38
SP - 7260
EP - 7274
JO - Physical Review B
JF - Physical Review B
SN - 2469-9950
IS - 11
ER -