Assessment of Mask Quality Assurance Method of Critical Layers with High MEEF

摘要

Currently, the wafer design rule is being reduced, and 130 AE100nm Lithography process development being accelerated. The specification of the mask quality assurance for 130 AE100nm lithography is about in the process of being fixed. It is commonly said that a 150nm Pixel grid is small enough for 130nm generation mask inspection. But We don't yet have verification results concerning whether the spec is adequate enough or not. This time, we had an experiment that at mask incoming inspection, KLA detect as repeating defect even through the mask shop inspection. We feed back this results to mask shop, and find out the route cause. Then we establish the assurance method for current and next generation mask inspection. We realized that the current mask inspection spec for each generation might not be adequate enough.