| 摘要 |
A cyclic voltammetric method for measuring the concentration of additives in a plating solution. The method generally includes providing the plating solution, having an unknown concentration of an additive to be measured therein and cycling the potential of an inert working electrode through a series of measurement steps. The series of measurement steps includes a metal stripping step including pulsing from an open circuit potential to a metal stripping potential between about 0.2 V and about 0.8 V, and holding the metal stripping potential until a corresponding current nears 0 mA/cm. The series of measurement steps further includes a cleaning step including pulsing from the metal stripping potential to a cleaning potential between about 1.2 V and about 1.6 V, and holding the cleaning potential for about 2 seconds to about 10 seconds. The series of measurement steps then includes a pre-plating step including pulsing from the cleaning potential to a pre-plating potential between about -0.2 V and about -0.5 V, and holding the pre-plating potential for about 2 seconds to about 10 seconds. The series of measurement steps additionally includes an equilibration step including pulsing from the pre-plating potential to the open circuit potential, and holding the open circuit potential for a predetermined time period, and a metal deposition step including scanning from the open circuit potential of the equilibration step to an additive sensitive potential, holding the additive sensitive potential for about 1 second to about 30 seconds, and scanning back to the open circuit potential. The method further includes plotting a profile of a deposition current resulting from the metal deposition potential as a function of time and integrating the deposition current to determine the concentration of the additive to be measured.
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