Analysis of failure mechanisms in electrically stressed Au nanowires

Abstract

An analysis of polycrystalline Au thin film interconnects of widths ranging from 850 to 25 nm and lengths ranging from 1.0 μm to 20 nm which are electrically stressed to the point of failure is presented. The mean time to failure for fixed current density is seen to decrease with decreasing wire width. The failure current density for a given wire width increases as the length decreases. An analysis of the temperature profile based on calculations of a simple model is presented which shows that this width-dependent behavior of narrow lines is not anticipated from the assumption of a homogeneous line subject to thermally-assisted electromigration alone.