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:
Oct. 18, 2011
Filed:
Feb. 18, 2009
Don Berrian, Topsfield, MA (US);
Steven Fong, San Jose, CA (US);
Don Berrian, Topsfield, MA (US);
Steven Fong, San Jose, CA (US);
Advanced Ion Beam Technology, Inc., San Jose, CA (US);
Abstract
A current branch circuit is electrically coupled with a Faraday cup and an operation amplifier separately. The Faraday cup, the current branch circuit and the operation amplifier are formed as a portion of an ion implanter. When the Faraday cup is electrically coupled with a ground through a conductive structure formed by an ion beam received by the Faraday cup, a current flows from the output of the operation amplifier to the current branch circuit to balance another current flow from the current branch circuit through the Faraday cup to the ground. By dynamically monitoring the voltage of the output of the operation amplifier, current flows through the Faraday cup to the ground and through the resistance of the conductive structure can be dynamically monitored. Accordingly, the difference between the ion current measured by the Faraday cup and the real ion current implanted to the wafer can be dynamically acquired to avoid overdosage of the wafer with the ion beam.