In‐Line Detection and Measurement of Molecular Contamination in Semiconductor Process Solutions

This paper discusses a fully automated metrology tool for detection and quantitative measurement of contamination, including cationic, anionic, metallic, organic, and molecular species present in semiconductor process solutions. The instrument is based on an electrospray ionization time‐of‐flight mass spectrometer (ESI‐TOF/MS) platform. The tool can be used in diagnostic or analytical modes to understand process problems in addition to enabling routine metrology functions. Metrology functions include in‐line contamination measurement with near real‐time trend analysis. This paper discusses representative organic and molecular contamination measurement results in production process problem solving efforts. The examples include the analysis and identification of organic compounds in SC‐1 pre‐gate clean solution; urea, NMP (N‐Methyl‐2‐pyrrolidone) and phosphoric acid contamination in UPW; and plasticizer and an organic sulfur‐containing compound found in isopropyl alcohol (IPA). It is expected that these uni...