Patent ID: 6639227
Filing Date: 2003-10-28
Classification: H01J

Abstract:
An ion implanter comprising:an ion beam generator providing a beam including ions to be implanted in a substrate, an accelerator to accelerate the beam with ions to a desired implant energy, and an energy filter for removing non-desired ions from the accelerated beam before implantation in a substrate, the filter including a beam channel having a beam entrance and a beam exit, said beam channel defining, between said entrance and said exit, a predetermined curved path, in a plane of curvature, for the accelerated beam, electrodes arranged for producing over said curved path an electric field in said plane transverse to said path, magnetic poles arranged for producing over said path a magnetic field transverse to said plane, and a controller for controlling the strength of said electric field and the strength of said magnetic field to operate the energy filter selectively at least in a first mode with substantially zero magnetic field strength and a selected constant electric field strength, and in a second mode with substantially zero electric field strength and a selected constant magnetic field strength.