Method for evaluating, monitoring or controlling the efficiency, stability, or exhaustion of a complexing or chelating agent present in a chemical solution used for oxidizing, dissolving, etching or stripping a semiconductor wafer

A method for evaluating saturation of a complexing or chelating agent in a solution comprising H.sub.2 O.sub.2 molecules and said complexing or chelating agent, said method comprising the steps of:

• a. monitoring a rate of decomposition of said H.sub.2 O.sub.2 molecules in said solution;
• b. detecting a change in the rate of said decomposition of said H.sub.2 O.sub.2 molecules in said solution, and
• c. correlating said change in the rate of decomposition of said H.sub.2 O.sub.2 molecules to the saturation of said complexing or chelating agent present in said solution.

A method for evaluating stability of a complexing or chelating agent in a solution comprising H.sub.2 O.sub.2 molecules and said complexing or chelating agent, said method comprising the steps of:

• a. monitoring a rate of decomposition of said H.sub.2 O.sub.2 molecules in said solution;
• b. detecting a change in the rate of said decomposition of said H.sub.2 O.sub.2 molecules in said solution, and
• c. correlating said change in the rate of decomposition of said H.sub.2 O.sub.2 molecules to the stability of said complexing or chelating agent present in said solution.