| 摘要 |
<p>PURPOSE:To prevent metal impurities from being eluted from the case which contains wafer cleaning chemicals into the chemicals by immersing a resin pellet into a mixed acid including an nitric acid and a hydrofluoric acid, so that metal impurities contained in the pellet are eliminated, and by forming a container using this pellet. CONSTITUTION:A mixed acid including 50%, nitric acid and 5 %, hydrofluoric acid is poured in a 'Teflon(R)' container, and a poly ethylene pellet is immersed into this acid. Nitrogen is subjected to bubbling at a temperature of 40 deg.C for four weeks, so that metal impurities of the pellet are dissolved into the acid. Thereafter, a container is produced from this pellet. Thereby, it is possible to significantly reduce the dissolution of metal impurities from the chemical container for wafer cleaning purposes, and to prevent the deterioration of the electric characteristics of the wafer caused by contamination by the chemicals, whereby it is possible to improve the integrated circuit product yield.</p> |
