| 摘要 |
Acid copper electroplating baths used to form ultra-fine circuitry features on semiconductor chips contain suppressor, anti-suppressor and leveler additives that must be closely controlled in order to obtain acceptable copper deposits. Cyclic voltammetric stripping (CVS) methods are available to measure the concentrations of the suppressor and anti-suppressor based on the effects of these additives on the copper electrodepositionrate. The present invention is a method that also uses measurements of the copper electrodepositionrate to determine the concentration of the leveler additive. The other two additives are included in the measurement solution at concentrations determined to provide the optimum compromise between minimal interference, high sensitivity and good reproducibility for the leveler analysis. In this case, measurement precision is greatly improved compared to that provided by inclusion of the interfering additives in the measurement solution at their concentrations in the bath sample at the time of the analysis, which would be the standard analytical procedure.
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