The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Nov. 22, 2016
Filed:
Sep. 29, 2014
Hseb Dresden Gmbh, Dresden, DE;
Bernd Srocka, Berlin, DE;
Ralf Langhans, Dresden, DE;
HSEB Dresden GmbH, Dresden, DE;
Abstract
An arrangement for optically detecting buried layers of flat objects having a plurality of layers, in particular wafers, containing a radiation source for illuminating the surface of the object at an angle; a polarization filter arranged in the beam path; and a detector for detecting radiation reflected by the surface of the object or transmitted by the object; is characterized in that that layer of the object which is closest to the radiation source at least partially transmits the radiation from the radiation source; the polarization filter transmits only radiation which is polarized parallel to the plane of incidence; and the surface of the object is illuminated at the Brewster angle. The surface of the object is preferably illuminated with unpolarized radiation and the polarization filter is arranged in the beam path between the surface of the object and the detector.