Steve Holland, Techcet Group, LLC, USA
ABSTRACT
Chemical Mechanical Polishing (CMP) has become a pervasive process used inmanufacturing virtually every sub-0.25 um generation semiconductor wafer that has a multilevel metal structure. CMP is generally considered to have a high cost of ownership due to the high consumables, and specifically slurry, cost. This article describes technologies that lower cost by delivering precise and reproducible amounts of slurry to the pad. No longerdo chip manufacturers have to use excess slurry flow to insure a minimumslurry flow. There is also antidotal evidence from early adapters ofcontrolled slurry flow devices that using reproducible amounts of slurry can enhance the wafer yields. Furthermore, improved slurry or chemistry metering to the CMP tool will allow optimizing the slurry used by process,or even at different steps of the process. These new flow controltechnologies allow controlled flow without compressive action on the slurry and without any obstruction to the flow, thus greatly reducing the risk of defect generation or particle agglomeration.