Microstructure, Stress, and Stress-Induced Damages in Damascene Cu

The adoption of Cu and various low-k materials as metal lines and dielectrics has aggravated new stress-related problems such as huge voiding near a via and via-cracking. It is thought that these failures are originated from the inherent characteristics of damascene Cu lines and thermo-mechanical properties of low-k dielectrics. In this study, we analyzed the microstructure and stress of damascene Cu with various line width and dielectric materials. The relationship between microstructure, stress and mechanical properties of dielectric materials was described though the finite element analysis based on experimental data. Finally, the effect of microstructure and dielectric materials on stress-related failure mechanism was discussed