Patent ID: 9039864
Filing Date: 2015-05-26
Classification: H01J,Y10T

Abstract:
1. Apparatus for coupling RF power to a plasma chamber, comprising: an electrically grounded chamber wall that surrounds a plasma chamber interior, wherein the electrically grounded chamber wall includes a chamber cover and a chamber side wall; a workpiece passageway in the chamber side wall; a showerhead that is electrically conductive and includes a plurality of gas passageways; and an RF impedance matching network comprising: (i) an input adapted to receive RF power, (ii) an output electrically connected to the showerhead, and (iii) an electrical ground that is electrically connected to a plurality of distinct, non-contiguous connection areas on the chamber cover; wherein said connection areas on the chamber cover collectively are characterized by a geometric centroid having a position that is offset away from the center of the chamber cover toward the workpiece passageway; and wherein said connection areas on the chamber cover collectively constitute the entire area on the chamber cover that is electrically connected to the electrical ground of the RF impedance matching circuit.