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. 29, 2005
Filed:
Dec. 08, 2003
Masato Muraki, Tokyo, JP;
Osamu Kamimura, Tokyo, JP;
Masaki Takakuwa, Tokyo, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
In a charged-particle-beam exposure apparatus for exposing a wafer using a charged-particle beam, an electron beam emitted from an electron source serving as a source of charged particles is substantially collimated by a collimator lens and irradiates an aperture array (), which has apertures for forming a plurality of electron beams used to expose a wafer. A current detector array has current detectors for measuring the intensities (currents) of electron beams at portions of the-aperture array other than where the apertures are present. During the wafer exposure operation, each current detector of the current detector array measures the intensity of the electron beam. The electron-beam intensity distribution is evaluated based upon the results of measurement and, when necessary, the optical power of electrostatic lenses that construct the collimator lens () is adjusted to uniformalize the electron-beam intensity distribution.