EFFICIENT ANALYSIS OF ORGANIC ADDITIVES IN AN ACID COPPER PLATING BATH

摘要

Suppressor and anti-suppressor additives in an acid copper sulfate plating bath are analyzed by the cyclic voltammetric stripping (CVS) method without cleaning or rinsing the cell between the two analyses. The suppressor analysis is performed first an the suppressor concentration in the resulting measurement solution is adjusted to a predetermined value corresponding to full suppression. This fully-suppressed solution is then used as the background electrolyte for the anti-suppressor analysis. This integrated analysis provides results comparable to those obtained with cell cleaning and rinsing between the analyses but significantl reduces the analysis time, consumption of expensive chemicals, and quality of hazardous waste generated. The figure shows a plot o Ar for a fully-suppressed supporting electrolyte of a commercial acid copper bath vs. volume fraction of anti-suppressor (accelerator) additive.