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. 28, 2005
Filed:
Oct. 02, 2002
Grant Kenji Larsen, Gloucester, MA (US);
Grant Kenji Larsen, Gloucester, MA (US);
Varian Semiconductor Equipment Associates, Inc., Gloucester, MA (US);
Abstract
A method of determining beam twist and/or calibrating tilt angles of an ion beam of an ion beam implanter relative to a first channel of a crystalline target. The method can be used to calibrate the machine to an accuracy which is comparable to the precision of variance of such angle. The method includes the steps of a) providing reference data defining a known relationship between the beam tilt and twist angles and beam channeling in at least one preselected second channel of the crystalline target, at least some of the data providing first and second reference tilt angles at which channeling occurs for a given twist angle, the first and second tilt angles being different, b) without varying the twist angle, measuring channeling severity around a range of estimated tilt angles surrounding each of said first and second reference tilt angles and determining from the measurements a point of maximum channeling severity within each range; and c) comparing the determined points to the reference data to determine the twist angle and/or calibrate the tilt angle.