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:
Dec. 24, 2002
Filed:
Jun. 23, 1999
Eugen Weimer, Essingen, DE;
Volker Drexel, Königsbronn, DE;
Abstract
In an electron beam device such as a raster electron microscope, two annular detectors are arranged at a distinct distance along the optical axis between a beam producer and an objective. The distance between the two detectors amounts to at least 25% of the distance between the specimen-side detector and the specimen. The source-side detector serves for detection of back-scattered or secondary electrons which are transmitted through the bore provided through the specimen-side detector for the passage of the primary particle beam. The source-side detector is a conversion diaphragm with an Everhart Thornley detector arranged laterally thereof. The conversion diaphragm produces secondary electrons on impingement of charged particles. By application of two detectors offset in the direction of the optical axis, the yield of the secondary electrons used for image production is increased. The secondary electrons are separated according to their angle of emergence from the specimen.