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:
Apr. 17, 2001
Filed:
Dec. 18, 1998
Jan M. Krans, Eindhoven, NL;
Marcellinus P. C. M. Krijn, Eindhoven, NL;
Alexander Henstra, Eindhoven, NL;
FEI Company, Hillsboro, OR (US);
Abstract
The detector,for the secondary electrons in a SEM provided with an electrostatic objective,is arranged ahead of the objective, thus enabling a high detection efficiency. According to the invention, the deflection of the beam is performed electrically and the deflection electrodes,are arranged between the detector,and the last two electrodes,of the objective. The beam deflection is realized by means of two oppositely directed electrical deflection fields in such a manner that the tilting point of the scanning motion is situated at the center,of the objective lens, thus avoiding additional lens defects and obstruction of the beam by the limited dimensions of the objective bore. This results in a large field of view, without loss of resolution. Furthermore, deflection by means of two oppositely directed fields has the effect that the paths,of the secondary electrons traveling to the detector,are shaped such that a larger part thereof reaches the detection material