Optical measurement arrangement, in particular for layer thickness measurement

US6618154B2 · kind B2 · utility

Assignee

• Leica Microsystems Jena GmbH · DE

Inventors

• Horst Engel · Gießen, DE
• Hakon Mikkelsen · Göttingen, DE
• Lambert Danner · Wetzlar, DE
• Matthias Slodowski · Jena, DE
• Kuno Backhaus · Stadtroda, DE
• Joachim Wienecke · Jena, DE

Key dates

• Filing date: May 2, 2001
• Grant date: Sep 9, 2003
• Expiry date: Aug 17, 2021

Classification

• Technology area (CPC G): Physics
• CPC primary: G01B11/0625
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

The invention refers to an optical measurement arrangement, in particular for layer thickness measurement and for ascertaining optical material properties such as refractive index, extinction factor, etc. of a specimen (P), having an illumination device (1) for emitting a measurement light beam (6), a beam splitter (8) for dividing the measurement light beam (6) into a specimen light beam (10) and a reference light beam (9), a measurement objective for directing the specimen light beam (10) onto a measurement location (M) on the surface of the specimen (P) and for acquiring the light reflected from the measurement location (M), and an analysis device (11) into which the reference light beam (9) and the specimen light beam (10) reflected from the specimen (P) are coupled in order to obtain information about the specimen (P), in particular about layer thicknesses present thereon. Light-guiding devices (23, 25) having a plurality of light-guiding fibers are provided for coupling the specimen light beam (10) and the reference light beam (9) into the analysis device (11). The result is to create a compact optical measurement arrangement that can be flexibly set up and is insensitive to …