Dynamic Extraction: A New Technique For Measuring Metallic Extractables From Chemical Handling System Components
Travis A. Lemke – FSI International, Chaska, MN
Donald C. Grant – C T Associates, Excelsior, MN
The extraction of inorganic contamination from fluid handling components degrades the quality of high purity semiconductor process chemicals. This paper presents a novel method, dynamic extraction, which measures the rate at which inorganic contaminants are extracted from components as a function of time. Dynamic extraction overcomes many of the shortcomings of conventional techniques. It allows prediction of the amount of contamination added to chemical in a process tool with time.
Dynamic extraction was used to measure metal ion extraction from pumps, piping and filters used in chemical handling systems. The extraction rate calculated for filters was compared to that predicted by theory. Comparison of the extracted metals and impurities in the piping polymer resins identified the source of the extractable contamination. Information concerning the amount and source of contamination added to process chemicals can be used to make informed decisions about selection and precleaning of components for chemical handling systems.
CTA Publication #21: Proceedings of the 13th Annual Techical Symposium: Partnering for Contamination-Free Manufacturing Millipore Corporation, Bedford, MA, Sept. 1995