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:
Oct. 29, 1991
Filed:
Oct. 23, 1990
Shigeru Noguchi, Tokyo, JP;
Dai Nippon Insatsu Kabushiki Kaisha, Tokyo, JP;
Abstract
The apparatus comprising an ion source producing an ion beam, a limiting aperture plate having a limiting aperture through which the ion beam passes, a condensor lens making the ion beam parallel, monitoring electrodes generating an electric field which deflect the paralleled ion beam, a monitoring aperture plate having a monitoring aperture and an objective lens focusing the ion beam is inspected. A voltage is applied to the monitoring electrodes to deflect the ion beam and an electric current which flows in the monitoring aperture plate is detected. A diameter of the limiting aperture is determined based on a change of the electric current with respect to deflecting of the ion beam. On a surface of a sample, secondary charged particles are generated by collision of the ion beam. Intensity of the particles can be detected instead of detecting the electric current. A dimameter of the limiting aperture can also be determined based on a change of the intensity with respect to deflecting of the ion beam.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile