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:
Jun. 12, 2012
Filed:
Oct. 18, 2007
Eiichi Iijima, Chigasaki, JP;
Guo Hua Shen, Chigasaki, JP;
Tohru Satake, Chigasaki, JP;
Ulvac, Inc., Kanagawa, JP;
Abstract
[Object] In the control of electron beam focusing of a pierce-type electron gun, any influences from the space charge effect and space charge neutralizing action within the electron gun are eliminated to attain complete control of an electron beam. [Solving Means] Feedback control of the pressure within the electron gun is performed by directly measuring temperature at an internal of the pierce-type electron gun. It is desirable that locations where the direct measurement of the temperature at the internal of the electron gun is performed are an anode () and a flow register (). Further, the direct measurement can be performed at any one of a ring, an aperture and an exhaust pipe provided at an outlet or an inlet of any one of a cathode chamber (), an intermediate chamber, and a scanning chamber (). Accordingly, all of stabilization of beam producing area (optimized design of electron gun itself), stabilization of beam transporting portion and stabilization of beam using portion have become appropriate.