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. 19, 1991
Filed:
May. 08, 1990
Tadamoto Tamai, Tokyo, JP;
Junichi Murakami, Ehime, JP;
Sumitomo Eaton Nova Corporation, Tokyo, JP;
Abstract
In an ion implantation apparatus which is for use in injecting an ion beam (11) onto a wafer (12) in a predetermined direction and which comprises an electric conductor tube (14) divided into a first tube section (17) and a second tube section (18) along the predetermined direction with an insulator interposed therebetween. The first tube section is located in proximity of the wafer and is grounded while the second tube section is remote from the wafer to be used as a target section which is bombarded by primary electrons to generate secondary electrons directed to the wafer. Undesired electrons are trapped by the first tube section and flow through the ground. The electric conductor tube may further comprise a third tube section (21) which is electrically insulated from the second tube section and which is remote from the wafer in comparison with the second tube section in the predetermined direction. The first and the third tube sections are controlled so as to adjust their diameters in dependency upon a diameter of the ion beam.