Simplified processes using conductive passivation film for the fabrication of Al micro-wires by electromigration

Abstract

Techniques for the fabrication of Al micro-wires by utilizing and controlling electromigration (EM), the phenomenon of atomic diffusion in a metallic film with high-density electron flow, have been investigated. These fabrication methods are based on atomic diffusion, using which accumulation was purposely induced in a specific area of a sample and discharged at a certain position by utilizing EM. In the creation of Al micro-wires, a passivation film is necessary. The passivation film forms the topmost layer and prevents unintended hillock formation. Passivation film is composed of the nonconductive material SiO2. We propose an improved approach for the fabrication of micro-wires using an electrically conductive passivation film composed of TiN. Conductive passivation film simplifies the process of fabricating samples and decreases the risk of the interruption in the current supply caused by open circuits along the Al line. As a result, the time and cost associated with the proposed method are less than half of those of the previously used techniques.