Post-Develop Blob Defect Reduction

摘要

This study reports on blob defect reduction and process impacts by Acid Rinse System. Blob defects that appear after develop are a common problem with i-line, KrF, ArF and ArF-immersion resists. Last year we reported Blob defects were influenced by the develop process and were able to be decreased by improving process. Furthermore we identified blob defects were caused from alkaline developer and could be reduced by neutralizing Acid Rinse.rnIn this work, we designed a novel develop process and system that reduced blob defects. We evaluated this system on the non-topcoat immersion resist. The blob defects on immersion resist were also eliminated by this system but affected by each resist surface condition. We also evaluated the impacts from Acid rinse for some kinds of patterns and resists, because we needed to indentify whether there were negatively process impacts.rnWe reports that Acid Rinse System significantly reduced blob defect counts, and whether influenced other process impacts. Finally we report the mechanism of the blob defects reduction.