Palladium coating thickness measurement
US9593931B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 1, 2013 |
| Grant date | Mar 14, 2017 |
| Priority date | — |
| Expiry date | Jul 14, 2035 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N27/26
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
The thickness of a palladium coating on copper (or another substrate) is measured by passing a cathodic current through a predetermined area of the coating in contact with an electrolytic solution and measuring the potential as a function of time. Protons from the electrolytic solution are electrochemically reduced to palladium hydride at cathodic potentials less negative than required for evolution of hydrogen. As formation of the PdH0.58 beta-phase throughout the Pd coating is completed, the cathodic potential increases rapidly to a cathodic potential plateau corresponding to evolution of hydrogen gas on the PdH0.58 surface. This step in the cathodic potential provides an endpoint time for the measurement. The absolute thickness of the Pd coating is calculated from the integrated cathodic charge passed up to the endpoint time and the predetermined area of the coating in contact with the electrolytic solution.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.