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:
Jan. 11, 1994
Filed:
Nov. 13, 1992
Toshiaki Sugiyama, Tokyo, JP;
NEC Corporation, , JP;
Abstract
The invention provides a novel scanning control system of preventing any over-scanning involved in an ion-implantation apparatus accomplishing an electrostatic X-scanning and a mechanical Y-scanning. The system includes a liner detecting arrangement for detecting over-scanning comprising a horizontal and sequential alignment of plural Faraday tubes. The detecting arrangement having a larger length than a diameter of a wafer is located behind the wafer mounted on a platen. The system also includes an X-scanning width control feature which is electrically connected to the detecting arrangement to fetch results of over-scanning detection. The X-scanning width control feature is determinative of a frequency of X-scanning associated with a width of X-scanning and supplies X-scanning frequency control voltage signals to X-deflector electrode plates making a pair thereby preventing over-scanning. The system further includes a Y-scanning speed control feature for controlling a speed of Y-direction movement of the wafer according to the frequency of the X-scanning thereby securing an uniformity of ion-implantation to the wafer.