METHOD FOR CONTROLLING CONCENTRATION OF PLATING BATH AND DEVICE THEREFOR

摘要

PROBLEM TO BE SOLVED: To maintain plating component concentration at a prescribed value by measuring the plating component concentration in a plating bath without sampling a plating solution. SOLUTION: A working electrode, a counter electrode and a reference electrode are immersed in the plating bath and these electrodes are connected with a potentiostat. A polarization curve of the plating bath is measured by using the potentiostat and critical current density between the working electrode and the counter electrode is obtained from the polarization curve and further the plating component concentration is obtained from the critical current density.