Thermal impact and process diagnosis of copper chemical mechanical polish

To effectively improve and control copper polish performance, a thermal impact study and a process diagnosis methodology were explored and proposed in this paper for 0.18 μm technology and beyond. Micro and macro thermal impacts on polishing of copper damascene wafers with trench structures were investigated by studying basic chemical kinetics of some mature copper slurries. Infrared thermal camera techniques were employed to in-situ monitor the macro thermal impact responses of the polish pad. Based on these responses, a process diagnosis algorithm was deduced for diagnosis of copper polish nonuniformity at the end of each polish. Several experiments have demonstrated the usefulness of these methodologies