Research Progress on Effect of Length Scale on Electrical Resistivity of Metals

With the development of micro/nano-technologies, microstructural scales or geometrical dimensions of metal conductors in the micro/nano-devices are becoming shrunk from macroscopic scale to micron scale, submicron scale and even nanometer scale, leading to the fact that the electrical resistivity of metal conductors at room temperature tends to exhibit evident size effects. Recent studies on the electrical resistivity of metal conductors at different length scales were reviewed in this paper, focusing on the effects of the geometrical scales of microscalematerials and of the scale of microstructures and defects in the materials as well as the relevant theoretical models. Finally the developing tendency of the investigations on the electrical resistivity of metal conductors and the service reliability of the microscale metals in the future are also addressed.