1992 Volume 18 Issue 5 Pages 576-583
To evaluate a performance of a water purification system, ultrapure water qual-ities were measured using conventional indexes and a new index, total solid (TS), denoting total impurities remaining after evaporation.
Tested ultrapure water was good enough for cleaning water for 16 Mbit wafers production according to an evaluation using conventional indexes, but it had a few impurities as indicated by the TS index.
From data analysis using the TS value and TOC (total organic carbon) value, it was thought that impurities dissolved in ultrapure water from each component in the ultrapure water process line, and that they differed from that in pure water supplied to this line.
