We have observed the evolution of stress in Al interconnect lines during the electromigration process using x-ray topography. in a new imaging configuration. Monochromatic x rays from a synchrotron source were reflected in a symmetric geometry by the Si substrate of the interconnect structure. We used a Fresnel zone plate in an off-axis imaging geometry to obtain magnified images of the sample. The results show the establishment of a constant stress gradient in the steady state where the electromigration damage is halted as well as time-dependent behavior of stress leading to that state. The imaging x-ray topography technique offers a number of advantages including better spatial resolution potential by eliminating the blur that occurs in conventional topography due to the. finite distance between the sample and the, detector. (C) 2003 American Vacuum Society.