蚀刻液中铜离子、硫酸、氟化氢铵、过氧化氢含量

Copper ion (Cu2+) contained in the etching solution is quantified using chelatometric titration method based on chemical reaction shown below. The AQUACOUNTER’s COM series Titrator with Photometric unit is provided with an optical probe and optimum filter. The effect of acidic compounds contained in etching treatment solution becomes deteriorated with repeated use in process. In this application, the sample may contain mainly the following two acidic compounds: sulfuric acid and ammonium hydrogen fluoride, three inflection points will appear in the measurement of used etching solution. By linking three condition files, a sequential titration can be performed to detect all end points. Hydrogen peroxide is contained in etching solutions as the surface treatment solution for copper foil on printed circuit boards, and it acts as oxidant or reductant depending on the compound it reacts with. The amount of the hydrogen peroxide can be determined by a typical redox titration with potassium permanganate titrant.