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:
Mar. 13, 2007
Filed:
Dec. 18, 2003
Rosario Mollica, Wilmington, MA (US);
Rosario Mollica, Wilmington, MA (US);
Varian Semiconductor Equipment Associates, Inc., Gloucester, MA (US);
Abstract
An apparatus and method are provided for optimizing ion implantation uniformity in a workpiece, such as a semiconductor wafer, which includes an ion beam generator for generating an ion beam, a beam scanning mechanism for diverging the ion beam and generating substantially parallel ion beam trajectories towards the workpiece, and an ion beam detector for measuring the ion beam current of the parallel ion beam trajectories as a function of the position of the ion beam detector. A uniformity controller filters the ion beam current measured by the ion beam detector to at least one predetermined resolution range and generates a uniformity signal to the beam scanning mechanism in response to the filtered ion beam current so that the workpiece is uniformly implanted. The uniformity controller determines a controllable frequency range for optimizing ion implantation uniformity control by making controllable frequencies observable and uncontrollable frequencies unobservable. As a result, the uniformity controller observes and controls spacially distributed components of the profiled beam current for optimizing the implantation of doses to the workpiece in a time and cost efficient manner.