The presence of colloidal silica in ultrapure water can cause silica residue to remain on water surfaces which later adversely affects the integrity of a semiconductor device. A general accepted approach to measuring colloidal silica is to take the difference between the values of a total silica and a dissolved silica measurement. In this study, there different techniques, colorimetry, ICP-AES and ICP-MS, were developed and evaluated for measuring total silica at ppb levels. Read more