Optical film topography and thickness measurement
US6999180B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 2, 2003 |
| Grant date | Feb 14, 2006 |
| Priority date | — |
| Expiry date | Feb 19, 2024 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01B11/2441
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An apparatus capable of measuring topography and transparent film thickness of a patterned metal-dielectric layer on a substrate without contact with the layer. A broadband interferometer measures an absolute phase of reflection at a plurality of wavelengths from a plurality of locations within a field of view on the metal-dielectric patterned layer on the substrate, and produces reflection phase data. An analyzer receives the reflection phase data and regresses the transparent film thickness and the topography at each of the plurality of locations from the reflection phase data. In this manner, the apparatus is not confused by the phase changes produced in the reflected light by the transparent layers, because the thickness of the transparent layers are determined by using the reflection phase data from multiple wavelengths. Further, the surface topography of the layer, whether it be opaque or transparent is also determinable. Thus, the present invention provides a means by which both transparent layer thickness and topography can be determined on an array surface of transparent and opaque layers, without contacting the surface of the layers.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.