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. 07, 1995
Filed:
Nov. 18, 1992
Takahisa Nagayama, Amagasaki, JP;
Naomitsu Fujishita, Amagasaki, JP;
Kazuhiko Noguchi, Amagasaki, JP;
Hidenobu Murakami, Amagasaki, JP;
Mitsubishi Denki Kabushiki Kaisha, Tokyo, JP;
Abstract
The present invention aims to extract a large electron beam and extend the service life of an electron source by effectively radiating an electron beam with low energy from a plasma chamber toward an ion extraction port, and optimally neutralizing space charges of ions in the vicinity of the ion extraction port. An electron source is installed behind a plasma chamber to control an extraction power supply, an electron accelerating power supply, and a lens power supply. Thereby, an electron beam is extracted from the power source, and accelerated. Then, the electron beam is carried through an electric field lens at a high speed, decelerated in the vicinity of the plasma chamber, then converged to radiate toward the ion extraction port. An aperture is installed at a crossover point of the electron beam to diminish backward flow of ionic gas from the plasma chamber to the electron source.