Method and an apparatus for detecting concentration of a chemical treating solution and an automatic control apparatus thereof
US5450870A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 16, 1993 |
| Grant date | Sep 19, 1995 |
| Priority date | — |
| Expiry date | Dec 16, 2013 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T137/2509
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
According to the present invention, the changing rate of the predetermined component concentration is determined, based on the difference between the predetermined component concentration in a chemical treating solution (a plating solution) which is analyzed this time and the predetermined component concentration analyzed last time, both measured by an analytical means, and the difference of each sampling time for analysis of each component concentration by the analytical means (140). Subsequently, the correction amount for the analyzed result of this time based on the changing rate obtained above and the elapsed time from the sampling point of time of the plating solution of this time for analysis of the plating solution by the analytical means to the current point of time (150), and then the analyzed result is corrected based on the resulting correction amount to compute or calculate the current concentration (160). As the result, the current concentration can be detected accurately regardless of the analyzing time of the plating solution by the analytical means.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.