Plasma reactor with minimal D.C. coils for cusp, solenoid and mirror fields for plasma uniformity and device damage reduction

摘要

A plasma reactor for processing a workpiece, includes a vacuum chamber defined by a sidewall and ceiling, and a workpiece support pedestal having a workpiece support surface in the chamber and facing the ceiling and including a cathode electrode. An RF power generator is coupled to the cathode electrode. Plasma distribution is controlled by an external annular inner electromagnet in a first plane overlying the workpiece support surface, an external annular outer electromagnet in a second plane overlying the workpiece support surface and having a greater diameter than the inner electromagnet, and an external annular bottom electromagnet in a third plane underlying the workpiece support surface. D.C. current supplies are connected to respective ones of the inner, outer and bottom electromagnets.