Vol.2 No.3 2009
Research paper : A marked improvement in the reliability of the measurement of trace moisture in gases (H. Abe)−217−Synthesiology - English edition Vol.2 No.3 (2009) Horiba STEC Co., Ltd., and Fujikin Inc., who cooperated in the development and improvement of the instruments. I am also thankful to Mr. Masaaki Maruyama of the Chemicals Evaluation and Research Institute, who helped organize the calibration service system. I thank all those who exchanged opinions about the performance of the conventional trace moisture analyzers.TerminologyFrost point: The temperature at which condensation occurs when a humid gas is cooled under constant pressure is called the dew point. The dew point is lower when there is less vapor content of the gas. It is called a frost point when frosting occurs below a freezing point.Primary measurement standard: A standard that is established without relation to a measurement standard of a quantity of the same kind. It has the highest metrological quality and must be given a complete table of uncertainty according to the SI.Enhancement factor: A coefficient to compensate for the change in vapor pressure caused by the presence of dry air; in the presence of dry air, the vapor pressure obtained is different from that when there is vapor only, because of the additional pressure generated by the dry air, dissolution into water, and interaction with water molecules.Term 1. Term 2.Term 3.ReferencesInternational Technology Roadmap for Semiconductors 2007, http://strj-jeita.elisasp.net/strj/ITRS07/Roadmap-2007.htmY. Kobayashi, H. Mangyo, H. Ono, T. Ikeda, K. Ikenaga, I. Matsumoto, K. Sugihara and K. Shibuya: Effects of Moisture Impurities in NH3 Gas on Nitride-Semiconductor Films Grown by Metal Organic Vapor Phase Epitaxy, Taiyo Nissan Giho (Technical Report of Taiyo Nissan), 26, 1-6 (2007) (in Japanese). http://www.tn-sanso.co.jp/jp/rd/report26.htmlH. H. Funke, B. L. Grissom, C. E. McGrew and M. W. 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