Showerhead faceplate having flow apertures configured for hollow cathode discharge suppression

Patent metadata

Field	Value
Publication number	US-11515124-B2
Application number	US-202117211256-A
Country	US
Kind code	B2
Filing date	Mar 24, 2021
Priority date	Oct 10, 2018
Publication date	Nov 29, 2022
Grant date	Nov 29, 2022

Abstract

A faceplate of a showerhead has a bottom side that faces a plasma generation region and a top side that faces a plenum into which a process gas is supplied during operation of a substrate processing system. The faceplate includes apertures formed through the bottom side and openings formed through the top side. Each of the apertures is formed to extend through a portion of an overall thickness of the faceplate to intersect with at least one of the openings to form a corresponding flow path for process gas through the faceplate. Each of the apertures has a cross-section that has a hollow cathode discharge suppression dimension in at least one direction. Each of the openings has a cross-section that has a smallest cross-sectional dimension that is greater than the hollow cathode discharge suppression dimension.

First claim

What is claimed is:

1. A method for manufacturing a faceplate of a showerhead for delivering process gas to a plasma generation region within a substrate processing system, comprising:
providing a disc having a bottom side and a top side, the bottom side of the disc to face the plasma generation region during operation of the substrate processing system, the top side of the disc to face one or more plenums into which one or more process gases are supplied during operation of the substrate processing system, the disc having an overall thickness as measured between the bottom side and the top side of the disc;
forming apertures through the bottom side of the disc, each of the apertures having a cross-section oriented parallel with the bottom side of the disc, the cross-section of each of the apertures having a size in at least one direction within a range extending from about 0.005 inch to about 0.04 inch; and
forming openings through the top side of the disc to intersect with at least one of the apertures within the disc to form a corresponding flow path for process gas through the disc, each of the openings having a cross-section oriented parallel with the top side of the disc, each of the openings formed to have a smallest cross-sectional dimension that is greater than a hollow cathode discharge suppression dimension.

2. The method as recited in claim 1 , wherein each of the openings is formed to extend through at least 50% of the overall thickness of the disc.

3. The method as recited in claim 1 , wherein each of the openings is formed to extend through at least 90% of the overall thickness of the disc.

4. The method as recited in claim 1 , wherein the apertures are formed to extend through less than the overall thickness of the disc.

5. The method as recited in claim 1 , wherein the apertures are formed to extend into the disc from the bottom side of the disc by a distance within a range extending from about 0.001 inch to about 0.03 inch.

6. The method as recited in claim 1 , wherein the hollow cathode discharge suppression dimension is within a range extending from about 0.005 inch to about 0.04 inch.

7. The method as recited in claim 1 , wherein the hollow cathode discharge suppression dimension is within a range extending from about 0.008 inch to about 0.018 inch.

8. The method as recited in claim 1 , wherein the openings are formed as respective circular holes.

9. The method as recited in claim 8 , further comprising:
arranging the openings in either a hexagonal lattice array, a square lattice array, a rectangular lattice array, a rhombic lattice array, a parallelogrammic lattice array, a Vogel pattern, or a customized pattern.

10. The method as recited in claim 9 , wherein the apertures are formed as slots that extend through the bottom side of the disc.

11. The method as recited in claim 10 , wherein each of the slots is formed to extend in a continuous manner across the bottom side of the disc, and wherein the slots are oriented parallel to each other.

12. The method as recited in claim 10 , wherein the slots are formed at locations of the openings, the slots formed separate from each other.

13. The method as recited in claim 12 , wherein each of the slots is formed to have a substantially rectangular cross-sectional shape in an orientation parallel with the bottom side of the disc, the slots oriented either parallel with respect to each other, or in an ordered manner with respect to each other, or in a random manner with respect to each other.

14. The method as recited in claim 12 , wherein each of the slots is formed to have a curved cross-sectional shape in an orientation parallel with the bottom side of the disc.

15. The method as recited in claim 14 , wherein each opening is formed to intersect a separate pair of slots.

16. The method as recited in claim 14 , wherein the curved cross-sectional shape is either a C-shape or a bracket shape.

17. The method as recited in claim 8 , wherein each of the apertures is formed to have a circular cross-sectional shape in an orientation parallel with the bottom side of the disc.

18. The method as recited in claim 8 , further comprising:
arranging the openings in a Vogel pattern, the apertures formed as grooves that extend through the bottom side of the disc, the grooves formed in a Vogel pattern to intersect the openings.

19. The method as recited in claim 1 , wherein the openings are formed as a first set of grooves that extend through the top side of the disc, and the apertures are formed as a second set of grooves that extend through the bottom side of the disc, the first set of grooves formed in a first Vogel pattern, the second set of grooves formed in a second Vogel pattern, the first and second Vogel patterns traversing in reverse direction with respect to each other.

20. The method as recited in claim 1 , wherein the openings are formed as a first set of grooves that extend through the top side of the disc, and the apertures are formed as a second set of grooves that extend through the bottom side of the disc, the first set of grooves formed in a radial-spoke pattern, the second set of grooves also formed in the radial-spoke pattern to intersect with the first set of grooves.

21. The method as recited in claim 1 , wherein the openings are formed as a first set of grooves that extend through the top side of the disc, and the apertures are formed as a second set of grooves that extend through the bottom side of the disc, the first set of grooves formed in a radial-spoke pattern, the second set of grooves formed in a concentric-circular pattern to intersect with the first set of grooves.

Assignees

• Lam Res Corp

Inventors

• Selep Michael John
• Breiling Patrick G
• Leeser Karl Frederick
• Thomas Timothy Scott
• Kamp David William
• Donnelly Sean M

Classifications

• H01J37/3244 Primary

  Gas supply means · CPC title

• H01J37/32596

  Hollow cathodes · CPC title

• H01J37/32623

  Mechanical discharge control means · CPC title