Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE · 2010 · 10 citations · 0 references
Natural SciencesChemical EngineeringChemistryAir PollutionAnalytical ChemistryEnvironmental ChemistryAir PollutantsAir Pollution MeasurementAir Pollution SourcesAir QualityEnvironmental Analytical ChemistryVolatile Organic CompoundsChemical Reaction MechanismsChemical Reaction NetworksClean Room Contamination ControlCleanroom Contamination ControlPhotolithographyPhotolithography CleanlinessReal-time ProcessingVolatile Organic Compound Monitoring
A case study of drastic photolithography defectivity reduction on i-line and Deep-UV (DUV) tools is presented. We show how this result is linked with reduction of Airborne Molecular Contamination (AMC) in clean room by combined installation of novel type of filters on tracks and on the recirculation air treatment. The root cause was identified to be the presence of acetic acid in clean room created by a reaction with the filters (mounted on track tools to exclude ammonia contamination of the process) and the photo solvent itself (here mainly 1-methoxy-2-propanol acetate: PGMEA). Crucial for the project success was the use of a real time monitoring tool to detect the sources of Volatile Organic Compounds (VOC). Finally, a model of chemical reaction of satellite defects creation is discussed based on a Time of Flight Static SIMS (TOF SSIMS) analysis together with new AMC specification for acetic acid for the photolithography area.