Plasma processing chamber with flexible symmetric RF return strap

摘要

Chambers for processing semiconductor wafers are provided. One such chamber includes an electrostatic chuck having a surface for supporting a substrate. A ground assembly is provided that surrounds a periphery of the electrostatic chuck. The ground assembly includes a first annular part and a second annular part and a space between the first annular part and the second annular part. A conductive strap having flexibility is provided. The conductive strap is annular and has a curved cross-sectional shape with a first end and a second end. The conductive strap is disposed in the space such that the first is electrically connected to the first annular part and the second end is electrically connected to the second annular part. The curved cross-sectional shape has an opening that faces away from the electrostatic chuck when the annular conductive strap is in the space.

主权项

1. A chamber for processing semiconductor wafers, comprising:
an electrostatic chuck having a surface for supporting a substrate; a ground assembly surrounding a periphery of the electrostatic chuck, the ground assembly including a first annular part and a second annular part and a space between the first annular part and the second annular part; and a conductive strap having flexibility, the conductive strap being annular and having a curved cross-sectional C-shape with a first end and a second end, the conductive strap disposed in the space such that the first end is electrically connected to the first annular part and the second end is electrically connected to the second annular part, wherein the curved cross-sectional C-shape has an opening that faces away from the electrostatic chuck and toward a surround wall of the chamber and the conductive strap remains within the space; wherein the first annular part has an L shape in cross-section and the second annular part has an L shape in cross-section, wherein a long side of the L shapes define a tubular portion and a short side of the L shapes define extensions that are parallel to each other and the short side of both of the L shapes of the first and second annular parts face in a same direction that is away from the electrostatic chuck and toward the surround wall of the chamber, wherein the space is between the short sides of the L shapes that define the extensions; wherein the first and second annular parts of the ground assembly are disposed below a perforated plasma confinement ring, and the L shape of the first annular part is configured to move vertically up toward the perforated plasma confinement ring and move vertically down away from the perforated plasma confinement ring.