Voltammetric measurement of halide ion concentration

A method for determining the concentration of chloride ion in an acid copper electroplating bath, comprising the steps of:

• measuring a copper electrodeposition rate parameter for a copper electrodeposition solution comprising copper ions, an anion, an acid, and at least one organic additive selected from the group consisting of suppressor, anti-suppressor and leveler;
• measuring the copper electrodeposition rate parameter for a test solution comprising the copper electrodeposition solution and a known volume fraction of the acid copper electroplating bath;
• measuring the copper electrodeposition rate parameter for at least one calibration solution comprising the copper electrodeposition solution and a known concentration of chloride ion;
• and
• comparing the copper electrodeposition rate parameters measured, in said steps of measuring, for the copper electrodeposition solution, the test solution, and the calibration solution to determine the concentration of chloride ion in the acid copper electroplating bath.

A method for determining the concentration of chloride ion in an acid copper sulfate electroplating bath, comprising the steps of:

• measuring a CVS copper stripping peak area for a copper electrodeposition solution comprising copper ions, sulfate ion, sulfuric acid, and at least one organic additive selected from the group consisting of suppressor, anti-suppressor and leveler;
• measuring the CVS copper stripping peak area for a test solution comprising the copper electrodeposition solution and a known volume fraction of the acid copper sulfate electroplating bath;
• measuring the CVS copper stripping peak area for at least one calibration solution comprising the copper electrodeposition solution and a known concentration of chloride ion;
• and
• comparing the CVS copper stripping peak areas measured, in said steps of measuring, for the copper electrodeposition solution, the test solution, and the calibration solution to determine the concentration of chloride ion in the acid copper sulfate electroplating bath.