Synchrotron x-ray microscopy studies on electromigration of a two-phase material

Abstract

Basic issues involving movement of conductive constituents and microstructural evolution from high current density in single phase materials are well documented. Recently, electromigration of conductive constituents in multiphase materials has gained attention due to the necessity of employing such alloys for interconnects in microelectronics. Reported studies on these alloys using complicated industrial geometry suffer from contributions such as current crowding. Hence a basic understanding on operative mechanisms during electromigration in multiphase alloys cannot be gained from these studies. Consequently, several mechanisms proposed from these studies involve fitting parameters and not well-understood complex diffusional processes. A joint configuration designed to avoid current crowding and associated local Joule heating is suitable for evaluating electromigration induced microstructural events. Synchrotron x-ray microscopy has provided information regarding two- and three-dimensional crystallographic orientations and strain fields in such joints, aiding the development of a basic understanding of electromigration in two-phase alloys.