Patent ID: 7462844
Filing Date: 2008-12-09
Classification: H01J

Abstract:
1. A method for improving doping uniformity in a high-tilt ion implantation, the method comprising the steps of: positioning a wafer along an axis perpendicular to an ion beam scan plane to form an angle between a surface of the wafer and a plane perpendicular to the ion beam; measuring a current of the ion beam at each of a plurality of locations by moving a current detector across the ion beam in the two dimensions of the ion beam scan plane in a path substantially coplanar with a surface of the wafer, the current detector measuring current at the plurality of locations that form a line; determining a spot beam profile from the current measured at each of the plurality of locations; adjusting at least one of an electrostatic lens and an electromagnetic lens such that a first and second dimension of each spot beam profile determined for each of the plurality of locations is substantially the same; and adjusting a uniformity of the ion beam current based on the measuring step.