Formation of Metallic Nanowires by Utilizing Electromigration

Abstract

A technique for forming metallic nanowires by utilizing electromigration, which is the phenomenon of atomic diffusion due to high current densities, is presented. These diffused atoms can be used for creating metallic nanowires. To specify the position at which a nanowire is formed, some specific conditions need to be established. These conditions are, first, to control the atomic diffusion so the accumulation of atoms produces the desired higher compressive stress; second, to design the structure to control the areas in which diffusion takes place; third, to adjust the thickness of the passivation layer deposited on the metal; and fourth, to form a small slot in the passivation layer through which the compressive stress is released by discharging the diffused atoms. It is shown that when these factors are satisfied, an Al nanowire can be successfully generated in a passivated metal track composed of an Al line buried in a W line.