Selective CVD Ru on W by sequential small molecule inhibitor treatments

This paper presents a method of sequential surface treatments that effectively extends the selectivity of metal deposition onto desired metal surfaces and suppresses undesired nuclei defects. Two different types of Small Molecule Inhibitors (SMIs) were used in this paper to demonstrate that Chemical Vapor Deposition CVD Ruthenium can be deposited on W metal surface selective to SiO2 dielectric surface. A Chemical Mechanical Planarization (CMP) process exposed both W and SiO2 on top of patterned surfaces which was then used for testing the concept of Area Selective Deposition (ASD). Whole wafer In-Line electrical Test (ILT) results were used to demonstrate the selectivity loss. Undesired nuclei defects on the SiO2 surface correspond to an increase in the measured leakage current.