Patent ID: 6562189
Filing Date: 2003-05-13
Classification: H01J

Abstract:
A plasma reactor comprising:a ceiling and side wall defining a vacuum chamber with an axis of symmetry about said side wall, said side wall having a vacuum side radially inwardly facing the interior of said chamber; a wafer support pedestal within said vacuum chamber facing said ceiling and having a pedestal wall having a vacuum side thereof radially outwardly facing a lower portion of said side wall and at least generally coaxial therewith whereby to define between said pedestal wall and said side wall a pumping annulus surrounding said wafer support pedestal; a plasma-confining tri-magnet assembly, comprising: a short magnet ring adjacent one wall, said one wall comprising one of said pedestal wall and said side wall, and at least generally coaxial with said one wall and having opposing poles spaced axially from one another by a gap distance which a fraction of the radial gap distance between said pedestal wall and said side wall, said short magnet ring having a magnetic orientation along one direction of said axis of symmetry; an elongate magnet ring adjacent the other one of said pedestal wall and said side wall in generally facing relationship with said short magnet ring and at least generally coaxial with said other one wall and having opposing poles spaced axially from one another by a pole displacement distance which is at least nearly as great as said gap distance, said elongate magnet ring having a magnetic orientation along said axis of symmetry.