Bevel etch profile control
Implementations described herein generally relate to methods and apparatus for processing a substrate. More particularly, implementations described herein relate to methods and an apparatus for bevel etch processing. In one embodiment, a method of cleaning a bevel edge of a semiconductor substrate is provided. The method includes placing a substrate on a cover plate inside of a processing chamber, the substrate having a deposition layer, which includes a center, and a bevel edge. A mask is placed over the substrate. The edge ring is disposed around/under the substrate. The method also includes flowing a process gas mixture adjacent the bevel edge, and flowing a purge gas through a first hole, a second hole, and a third hole of the mask in the center of the substrate adjacent a top of the substrate.
1. A method comprising:
placing a substrate on a cover plate inside of a processing chamber, the substrate having a dielectric layer, a center, and a bevel edge, wherein the processing chamber comprises a mask disposed above the substrate and an edge ring disposed under the substrate, and wherein the edge ring has an annular body;
raising the edge ring to contact the mask;
flowing a process gas comprising an etchant along an outer surface of the mask and to the bevel edge, wherein the process gas is ignited to produce a plasma;
exposing an upper surface of the substrate at the bevel edge to the process gas; and
flowing a purge gas from two or more holes positioned on an inner surface of the mask to the center of the substrate and adjacent a top of the substrate.
2. The method of claim 1 , wherein the cover plate is disposed on a substrate support.
3. The method of claim 1 , wherein the cover plate has scalloped edges.
4. The method of claim 1 , wherein the cover plate has a central aperture and a plurality of openings surrounding the central aperture.
5. The method of claim 1 , wherein the plasma is produced by a plasma source adjacent the mask.
6. The method of claim 1 , wherein the distance between the substrate and the mask is less than 100 mil.
7. The method of claim 1 , wherein the process gas comprises N 2 , O 2 , NF 3 , Ar, He, or any combination thereof.
8. A method comprising:
placing a substrate on a cover plate inside of a processing chamber, the substrate having a dielectric layer, a center, and a bevel edge, wherein the processing chamber comprises a mask disposed above the substrate and an edge ring disposed under the substrate;
raising the edge ring to contact the mask;
flowing a process gas comprising an etchant along an outer surface of the mask and to the bevel edge, wherein the process gas is ignited to produce a plasma;
exposing an upper surface of the substrate at the bevel edge to the process gas; and
flowing a purge gas from two or more holes positioned on an inner surface of the mask to the center of the substrate and adjacent a top of the substrate.
9. The method of claim 8 , wherein the cover plate is disposed on a substrate support.
10. The method of claim 8 , wherein the cover plate has scalloped edges.
11. The method of claim 8 , wherein the cover plate has a central aperture and a plurality of openings surrounding the central aperture.
12. The method of claim 8 , wherein the plasma is produced by a plasma source adjacent the mask.
13. The method of claim 8 , wherein the distance between the substrate and the mask is less than 100 mil.
14. The method of claim 8 , wherein the process gas comprises N 2 , O 2 , NF 3 , Ar, He, or any combination thereof.
15. A method comprising:
placing a substrate on a cover plate inside of a processing chamber, the substrate has a center and a bevel edge and comprises a dielectric layer thereon, wherein the processing chamber comprises a mask disposed above the substrate and an edge ring disposed under the substrate, and wherein the edge ring comprises a ceramic material;
raising the edge ring to contact the mask;
flowing a process gas along an outer surface of the mask and to the bevel edge, wherein the process gas comprises N 2 , O 2 , NF 3 , Ar, He, or any combination thereof, and wherein the process gas is ignited to produce a plasma;
exposing an upper surface of the substrate at the bevel edge to the process gas and etching the dielectric layer; and
flowing a purge gas from two or more holes positioned on an inner surface of the mask to the center of the substrate and adjacent a top of the substrate.
16. The method of claim 15 , wherein the cover plate is disposed on a substrate support.
17. The method of claim 15 , wherein the cover plate has scalloped edges.
18. The method of claim 15 , wherein the cover plate has a central aperture and a plurality of openings surrounding the central aperture.
19. The method of claim 15 , wherein the plasma is produced by a plasma source adjacent the mask.
20. The method of claim 15 , wherein the distance between the substrate and the mask is less than 100 mil.