Apparatus for measuring the thickness of a thin film having eddy current coil sensor
US6700370B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 5, 2001 |
| Grant date | Mar 2, 2004 |
| Priority date | — |
| Expiry date | Nov 5, 2021 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01B21/08
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
The thickness of a conductive film formed on a substrate can be measured efficiently at low cost with a film thickness measuring apparatus of the invention, which includes an eddy current coil sensor, disposable at a predetermined position near a conductive film, for generating a predetermined eddy current in the conductive film and for detecting a magnetic field caused by the eddy current. The apparatus also includes a displacement sensor for measuring a displacement between the eddy current coil sensor and the conductive film. The thickness of the conductive film is measured in accordance with a variation in inductance of the eddy current coil sensor and the amount of displacement measured by the displacement sensor.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.