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:
Mar. 18, 2008
Filed:
Mar. 29, 2004
Josef Sellmair, Freising, DE;
Josef Sellmair, Freising, DE;
ICT Integrated Circuit Testing Gesellschaft, Heimstetten, DE;
Abstract
An apparatus for producing a beam of charged particles is provided, which comprises an emitter () and a switching device () adapted to switch between first, second and third beam current levels, wherein the beam current at said first current level is suitable for writing a pixel of an image on the surface of a sample, the beam current at said second current level is suitable for not writing a pixel on the surface of said sample, and the beam current at said third current level is lower than the beam current at the second current level. Furthermore, a method of controlling the beam current of a charged particle beam is provided, comprising the steps of switching the beam current of said charged particle beam between first and second current levels, wherein the beam current at said first current level is suitable for writing a pixel of an image on the surface of a sample and the beam current at said second current level is suitable for not writing a pixel on the surface of said sample, and switching the beam current to a third voltage level, wherein the beam current at said third current level is lower than the beam current at the second current level.