| 摘要 |
<p>PROBLEM TO BE SOLVED: To detect soil and foreign matter included in a chemical or the like, primarily an organic soil and contamination in real time with high sensitivity at low costs by using a detect plate which multiple reflects infrared rays. SOLUTION: The apparatus for evaluating a liquid used in manufacturing semiconductor devices or the like by, e.g. the FTIR method has a detect plate 5 of, for example, an Si wafer or a GaAs wafer provided in a liquid cell 4 to which the liquid 10 to be measured is supplied. For instance, one end face of the detect plate 5 is shaped like a mountain and the other face is mirror polished at right angles. An infrared incident light 12 enters the mountain-shaped end face, is repeatedly totally reflected to fetch information on the liquid on an interface of the wafer, is projected from the opposite face to the mountain- shaped incident face and enters a detector 2. The fetched information is displayed or the like as data of electric signals by a measuring system 26. The apparatus can be constituted so that the infrared light is brought in from one of the opposite end faces of the detect plate 5 and is projected from the other face.</p> |
