The impact of dielectric materials on the reliability of advanced copper (Cu) interconnect is of growing importance. The effect of barrier dielectrics and low-k materials of Inter-Level Dielectric (ILD) on the electromigration (EM) in the line and via-line structure of dual-damascene Cu interconnects was analyzed. The resulting electromigration behavior can then be attributed to Cu barrier layer or low-k dielectrics, depending on the test structure. The SiN barrier layer showed a better electromigration endurance compared to SiC barrier layer for narrow Cu line structure. We had also observed that the carbon-doped oxide (CDO) low-k samples had a higher drift velocity, which results in less electromigration endurance on the via-line structure compared to fluorosilicate glass (FSG). (c) 2005 Elsevier B.V. All rights reserved.