Method for monitoring metal ion concentrations in plating baths
US4725339A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 13, 1984 |
| Grant date | Feb 16, 1988 |
| Priority date | — |
| Expiry date | Feb 13, 2004 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N27/49
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A rotating disk electrode system operates at constant speed in a solution whose metal ion concentration is held constant at multiple concentrations within a range of concentration. The current at the working electrode is recorded, while the potential at the working electrode is swept at a predetermined rate for each of the concentration values. The diffusion limiting current is determined for each of the concentration values. Then the rotating disk electrode system is operated continuously in a metal plating bath whose metal ion concentration can vary. A voltage applied to the working electrode produces a current at the electrode whose magnitude is compared to the values of the previous calibration to determine the current metal ion concentration. Alternatively, a rotating disk electrode system is operated over a range of speeds in a solution whose ion concentration is held constant over a range of concentration. Current at the working electrode is measured for a given electric potential applied to the working electrode. In this way, a calibration relationship between the current at the electrode and the range of metal ion concentrations is established which can be used with curren…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.