Barrier Metal Slurry for Low Defect Copper Damascene Chemical Mechanical Polishing

Abstract

To make a superior flat surface in Cu damascene process, chemical mechanical planarization or polishing (CMP) is inevitably utilized. CMP process uses slurry reacts with various materials on wafer surface such as Cu line, barrier metal, and oxide dielectric. Thus, slurry should have balanced reaction between mechanical and chemical effect to achieve flatness. Not only flatness but also defect occurrence on the surface is another important parameter in mass semiconductor fabrication. In present study, we developed slurry having lower defect occurrence than conventional one. Optimizations are applied to components in the slurry such as abrasive morphology, abrasive surface treatment and organics acids in slurry chemical