Patent ID: 7683347
Filing Date: 2010-03-23
Classification: H01J

Abstract:
1. A method for improving ion implantation throughput and dose uniformity, the method comprising the steps of: measuring an ion beam density distribution in an ion beam; calculating an ion dose distribution across a predetermined region of a workpiece that results from a scan velocity profile, wherein the scan velocity profile comprises a first component and a second component that control a relative movement between the ion beam and the workpiece in a first direction and a second direction respectively, wherein the ion dose distribution is based at least in part on the ion beam density distribution, and wherein the first component is a beam scan velocity profile and the second component is a workpiece scan velocity profile; selecting a workpiece rotation mode based on whether an ion beam profile in the first direction has a predominantly symmetric or asymmetric component in the first direction; adjusting the first component of the scan velocity profile to further enhance the predominantly symmetric or asymmetric component; and adjusting, based on the adjusted first component and the selected workpiece rotation mode, the second component of the scan velocity profile to achieve a desired ion dose distribution.