Research on Chemical Mechanical Polishing Mechanism of Novel Diffusion Barrier Ru for Cu Interconnect

Description

This thesis addresses selected unsolved problems in the chemical mechanical polishing process (CMP) for integrated circuits using ruthenium (Ru) as a novel barrier layer material. Pursuing a systematic approach to resolve the remaining critical issues in the CMP, it first investigates the tribocorrosion properties and the material removal mechanisms of copper (Cu) and Ru in KIO4-based slurry. The thesis subsequently studies Cu/Ru galvanic corrosion from a new micro and in-situ perspective, and on this basis, seeks ways to mitigate corrosion using different slurry additives. The findings presented here constitute a significant advance in fundamental and technical investigations into the CMP, while also laying the groundwork for future research. Front Matter ....Pages i-xviii Introduction (Jie Cheng)....Pages 1-27 Material Removal Mechanism of Cu in KIO4-Based Slurry (Jie Cheng)....Pages 29-48 Material Removal Mechanism of Ru in KIO4-Based Slurry (Jie Cheng)....Pages 49-73 Tribocorrosion Investigations of Cu/Ru Interconnect Structure During CMP (Jie Cheng)....Pages 75-89 Micro-galvanic Corrosion of Cu/Ru Couple in KIO4 Solution (Jie Cheng)....Pages 91-105 Galvanic Corrosion Inhibitors for Cu/Ru Couple During Chemical Mechanical Polishing of Ru (Jie Cheng)....Pages 107-119 Synergetic Effect of Potassium Molybdate and Benzotriazole on the CMP of Ru and Cu in KIO4-Based Slurry (Jie Cheng)....Pages 121-134 Conclusions and Recommendations (Jie Cheng)....Pages 135-137