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. 14, 2009
Filed:
Aug. 30, 2006
Diederik Jan Maas, Breda, NL;
Sjoerd Antonius Maria Mentink, Eindhoven, NL;
Jeroen Jan Lambertus Horikx, Eindhoven, NL;
Bert Henning Freitag, Eindhoven, NL;
Diederik Jan Maas, Breda, NL;
Sjoerd Antonius Maria Mentink, Eindhoven, NL;
Jeroen Jan Lambertus Horikx, Eindhoven, NL;
Bert Henning Freitag, Eindhoven, NL;
Fei Company, Hillsboro, OR (US);
Abstract
The invention relates to a method for determining lens errors in a Scanning Electron Microscope, more specifically to a sample that enables such lens errors to be determined. The invention describes, for example, the use of cubic MgO crystals which are relatively easy to produce as so-called 'self-assembling' crystals on a silicon wafer. Such crystals have almost ideal angles and edges. Even in the presence of lens errors this may give a clear impression of the situation if no lens errors are present. This enables a good reconstruction to be made of the cross-section of the beam in different under- and over-focus planes. The lens errors can then be determined on the basis of this reconstruction, whereupon they can be corrected by means of a corrector.