Determination of leveler «Top Lucina α-3» in acid copper baths by response curve technique (RC) (Okuno Chemical Industries)

Significance of the Topic

The leveler Top Lucina α-3 plays a crucial role in acid copper plating baths by ensuring uniform deposit thickness and preventing defects on plated surfaces.

Objectives and Overview of the Study

This application note presents a method to quantify Top Lucina α-3 using the response curve (RC) technique combined with cyclic voltammetric stripping (CVS). It aims to provide a reliable, rapid assay for quality control in plating processes.

Methodology and Instrumentation

The procedure employs a platinum rotating disk electrode (Pt-RDE) with Ag/AgCl/KCl reference and platinum auxiliary electrodes. Key parameters include:

• Electrolyte: acid copper bath or virgin make-up solution with CuSO4, H2SO4 and NaCl
• Working electrode: Pt-RDE at 2000 rpm
• CVS settings: potential range 1.625 V to -0.175 V, step 0.006 V, sweep rate 0.1 V/s
• Calibration via RC saturated solutions

Main Results and Discussion

The technique demonstrated a clear stripping peak for copper near 0.2 V, with signal intensity proportional to leveler concentration. The calibration curve exhibited linearity across the tested range, supporting accurate quantification within typical bath concentrations. The method showed good reproducibility and rapid measurement times.

Benefits and Practical Applications of the Method

This approach offers:

• No sample pretreatment required
• Fast analysis suitable for in-process monitoring
• High sensitivity and selectivity for leveler detection

Future Trends and Potential Applications

Adapting this electroanalytical technique for automated inline monitoring and expanding its use to multi-component bath additives represent promising directions. Integration with process control systems and miniaturized electrode designs could enable real-time quality assurance.

Conclusion

The RC-CVS method provides a straightforward, sensitive tool for quantifying Top Lucina α-3 in acid copper baths, enhancing process control in electroplating operations.

Reference

• Okuno Chemical Industries, Application Note No. V-184, Version 1.0