Before a new analytical electrochemical method is developed, the interactions between bath components should be investigated and understood. For this purpose, we utilized an electrochemical cell with three electrodes connected to a potentiostat/galvanostat. We studied the responses of organic components under varying electrochemical and hydrodynamic conditions as well as at different concentrations of bath components. Fig. 1 shows the electrochemical responses of organic additives used in commercial lead-free plating baths [2]. All tests were performed with the working and counter platinum electrodes and a low maintenance Ag/AgCl double junction reference electrode.
Optimized electrochemical analysis parameters enable the determination of a wide range of concentrations of organic plating additives without interference from other bath components.
Analysis of organic additives can be performed with relatively simple fluidics that include a single electrochemical cell with accurate temperature control. Typical analysis steps include fast electrode conditioning in support electrolyte, several injections of plating solution to determine changes in plating rate, and then subsequent calculation of the concentrations.
This presentation will provide more information related to the electrochemical behavior of organic additives and inorganic components. Results of Electrochemical Impedance Spectroscopy investigations will also be presented. Results of electrochemical analyses will be correlated to data obtained with an HPLC analytical technique. The presentation will be concluded with a discussion of analytical results for each organic additive at different concentration levels.
References:
- Pavlov, D. Lin, E. Shalyt, I. Tsimberg, “Electrochemical Analysis of Semiconductor Plating Baths”, MAM Conference, Milano, Italy, March 18-21, 2018
- Foyet, M. Clauss, W. Zang-Beglinger, J. Woertink, Y. Qin, J. Prange, P. Lopez, , “Electroplating baths of silver and tin alloys”, US Patent, US9512529B2