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:
Apr. 26, 1994
Filed:
Mar. 02, 1993
Hisato Tanaka, Nirasaki, JP;
Naoki Takayama, Koufu, JP;
Tokyo Electron Limited, Tokyo, JP;
Abstract
Electric discharge gas is made into auxiliary plasma in an electron generating chamber and electrons in the generated auxiliary plasma are introduced into an ion generating chamber. Electrons collide with molecules of material gas in the ion generating chamber to generate primary plasma. Ions in the ion generating chamber are drawn out of the primary plasma through an opening of the ion generating chamber. A magnetic field is formed by electromagnets in order to bring the plasma in the ion generating chamber into a concentrated state. A control unit is provided to store data representing optimum magnetic field intensities for ions of different types involved. The control unit so controls current applied by the power supply for the electromagnets as to produce an optimum magnetic field intensity for the type of ions to be drawn.