Symmetric plasma process chamber
Embodiments of the present invention provide a plasma chamber design that allows extremely symmetrical electrical, thermal, and gas flow conductance through the chamber. By providing such symmetry, plasma formed within the chamber naturally has improved uniformity across the surface of a substrate disposed in a processing region of the chamber. Further, other chamber additions, such as providing the ability to manipulate the gap between upper and lower electrodes as well as between a gas inlet and a substrate being processed, allows better control of plasma processing and uniformity as compared to conventional systems.
1. A plasma processing apparatus, comprising:
an upper liner configured to be disposed within a chamber body and having an inner surface that circumscribes a processing region within the chamber body, wherein the upper liner has a cylindrical wall with a plurality of slots defining openings extending from the inner surface to an outer surface and arranged about a central axis of the upper liner, the upper liner is configured to be arranged symmetrically about a central axis of a substrate support assembly; and
one or more backing liners in conductive contact with the outer surface of the cylindrical wall of the upper liner to cover the openings for all but one of the plurality of slots, wherein a slit valve door is configured to cover the remaining one of the plurality of slots during processing.
2. The plasma processing apparatus of claim 1 , further comprising a mesh liner annularly disposed about the central axis of the substrate support assembly and configured to be electrically coupled to the upper liner.
3. The plasma processing apparatus of claim 2 , wherein the mesh liner comprises a bottom wall and an outer wall extending at an outward and upward angle from the bottom wall.
4. The plasma processing apparatus of claim 3 , wherein the outer wall has a plurality of apertures formed therethrough.
5. The plasma processing apparatus of claim 4 , wherein the plurality of apertures are positioned symmetrically about a center axis of the mesh liner.
6. The plasma processing apparatus of claim 1 , wherein the slit valve door and the upper liner are comprised of the same material.
7. The plasma processing apparatus of claim 1 , wherein the slit valve door and the backing liner are comprised of the same material.
8. The plasma processing apparatus of claim 1 , wherein the upper liner further comprises a bottom wall extending inwardly from the cylindrical wall, wherein the bottom wall has a plurality of passages formed therethrough.
9. The plasma processing apparatus of claim 8 , wherein the plurality of passages formed in the bottom wall are symmetrically positioned about the central axis of the substrate support assembly.
10. A plasma processing apparatus, comprising:
a lid assembly and a chamber body enclosing a processing region;
a substrate support assembly disposed in the processing region;
an upper liner disposed within the chamber body and circumscribes the processing region, wherein the upper liner has a cylindrical wall with a plurality of slots defining openings extending from an inner surface that circumscribes the processing region, to an outer surface and arranged symmetrically about a central axis of the substrate support assembly;
a slit valve door assembly positioned to align a slit valve door with one of the plurality of slots in the upper liner;
a backing liner in conductive contact with the outer surface of the cylindrical wall of the upper liner to cover the opening for at least one of the remaining of the plurality of slots; and
a mesh liner annularly disposed about the substrate support assembly and configured to be electrically coupled to the upper liner.
11. The plasma processing apparatus of claim 10 , wherein the upper liner further comprises a bottom wall extending inwardly from the cylindrical wall, wherein the bottom wall has a plurality of passages formed therethrough, and wherein the plurality of passages are symmetrically positioned about the central axis of the upper liner.