The Role of Stacking Faults on the Atom Migration in Ag Nanowire Under Biasing

Abstract

In this study we investigated the effect of stacking faults (SFs) on electromigration in silver nanowires (AgNWs) in particular, with respect to their effects on necking and void growth. We used the galvanic replacement reaction to synthesize the AgNWs in bulk at low cost. By varying the concentration of silver nitrate, we obtained AgNWs with and without SFs. In situ TEM analysis provided strong evidence that the SFs could effectively suppress the migration of surface atoms. Furthermore, an investigation of the void growth process revealed that SF facets parallel to the {111} plane contributed to the anisotropic change in morphology, and slowed down the rate of void growth by 135 times. Thus, planar defects can be beneficial to extending the lifetimes of devices by causing intrinsic changes to the material properties.

Keywords: electromigration, Ag nanowires, stacking faults, current-resist ability, galvanic replacement reaction