Patent ID: 7988815

Claim:
A plasma reactor comprising: a vacuum chamber having a cylindrical side wall, a ceiling and a floor; a workpiece support pedestal in said chamber defining a pumping annulus between said pedestal and said side wall, said workpiece support pedestal comprising a grounded surface adjacent said floor; an RF power applicator, and a process zone defined between said ceiling and said pedestal; a pumping port through said floor; a dielectric element between said grounded surface of said pedestal and said floor; an annular conductive grill in said pumping annulus and displaced above said floor by a grill-to-floor gap, and providing a current path from said side wall to said grounded surface of said pedestal, said grill being generally symmetrical relative to an axis of symmetry of said chamber; a slit valve opening through a circumferential portion of said cylindrical side wall, said slit valve opening being axially confined within an annular section of said cylindrical side wall; at least a first dielectric circular ring in said cylindrical side wall adjacent an axial boundary of said annular section of said side wall; and an array of conductive straps providing axial current paths bypassing said annular section of said cylindrical side wall, each of said conductive straps having a pair of ends, one end being electrically connected to said side wall above said annular section and the other end being electrically connected to said side wall below said annular section, said straps being routed to avoid blocking access to said slit valve opening.