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:
Sep. 07, 1999
Filed:
Feb. 25, 1997
Kenji Ohtoshi, Numazu, JP;
Munehiro Ogasawara, Fujisawa, JP;
Jun Takamatsu, Asaka, JP;
Toru Koike, Tokyo, JP;
Kazuyoshi Sugihara, Yokosuka, JP;
Kabushiki Kaisha Toshiba, Kawasaki, JP;
Abstract
A charged beam applying apparatus comprises a column at least having a charged beam generation section and optical system for controlling the charged beam and a chamber for holding a specimen in place which is exposed with the charged beam. At least one inner portion of the column is formed of a specific material whose an atomic number is equal or less than 22. When a contamination is cleaned off in the column through the utilization of an oxidation effect, an oxide film is sometimes formed inside the column. The electric charging of the oxide film causes a beam control error. The specific material such as the metal of the atomic number causes very much less such error. This is because such specific material involves less emission of secondary electrons and less electric charging in the oxide film formed.