Potentiodynamic Approach for Determination of Organic Additives Concentration in Electroplating Solutions

A cost-effective method for fast determination of organic additives in electroplating baths is proposed in this paper. The method relies on a voltage-current scan procedure that is performed on a sample from the main bath and not on a whole volume of the bath, thus reducing the time spent for the evaluation. The objective of the scan is to determine the chemical state of the solution in order to control the effectiveness and quality of the plating process. Results obtained using the sample taken from the main bath is then compared to the standard sample where known - i.e. fresh additive as supplied by the manufacturer is used. The voltage-current scan procedure takes place in a three electrode miniature electrochemical cell with a rotating platinum cathode. During the measurement procedure, a voltage between the control electrode and the cathode is controlled at a constant rate from negative to positive voltage limits. For that purpose, a voltage controlled current source is used. The anode-cathode voltage, the measurement electrode-cathode voltage and the current through the plating bath are scanned and data is then sent to the supervising LabView software on the personal computer for further calculations