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:
Feb. 16, 1993
Filed:
Apr. 18, 1991
Hironobu Matsui, An Yang, KR;
Mikio Ichihashi, Kodaira, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
A charged particle beam apparatus includes at least a charged particle source and an objective lens for converging onto a sample a charged particle beam emitted by the charged particle source. The objective lens is an electrostatic objective lens constituted by a first and a second electrode positioned opposite to each other and having openings through which the charged particle beam passes. The first electrode and the second electrode are located close to the charged particle source and to the sample, respectively. The first electrode is supplied with a positive potential as opposed to the second electrode when the charged particle beam is a negatively charged particle beam. Conversely, the first electrode is supplied with a negative potential as opposed to the second electrode when the charged particle beam is a positively charged particle beam. The principal plane of the electrostatic objective lens is located on the side of the sample below the bottom plane of the second electrode. This constitution allows the apparatus to be very small in size and to provide high resolution for observation.