Method and apparatus for an improved baffle plate in a plasma processing system

• US 6,837,966 B2
• Filed: 09/30/2002
• Issued: 01/04/2005
• Est. Priority Date: 09/30/2002
• Status: Active Grant

• Current Assignee: Tokyo Electron Limited
• Original Assignee: Tokyo Electron Limited
• Inventors: Nishimoto, Shinya, Nakayama, Hiroyuki, Mitsuhashi, Kouji
• Primary Examiner(s): LUND, JEFFRIE ROBERT
• Application Number:
  US10/259,382
• Publication Number:
  US 20040060658A1
• Time in Patent Office: 827 Days
• Field of Search: 156/345.49, 156/345.51, 156/345.29, 156/345.41, 156/345.43, 156/345.47, 156/345.48, 204/298.07, 118/715, 118/723.R, 118/723.MW, 118/723.ME, 118/723.AN, 118/723.E, 118/723.ER, 118/723.I, 118/723.IR
• US Class Current: 156/345.29
• CPC Class Codes: H01J 37/32623 Mechanical discharge control means
• CPC Class Codes: H01J 37/32633 Baffles
• CPC Class Codes: H01J 37/32834 Exhausting

Abstract

The present invention presents an improved baffle plate for a plasma processing system, wherein the design and fabrication of the baffle plate advantageously provides for a uniform processing plasma in the process space with substantially minimal erosion of the baffle plate.

Claims

1. An improved baffle plate in a plasma processing system comprising:

a ring comprising an upper surface, a lower surface, an inner radial edge coupled to said upper surface and said lower surface, an outer radial edge coupled to said upper surface and said lower surface, and at least one passageway coupled to said upper surface and to said lower surface and configured to permit the flow of a gas therethrough, wherein said upper surface comprises a first mating surface proximate said outer radial edge, said lower surface comprises a second mating surface proximate said outer radial edge and a plurality of fastener mating surfaces proximate said inner radial edge, and each of said at least one passageway comprises an internal passageway surface; and

a protective barrier coupled to a plurality of exposed surfaces of said baffle plate, wherein said exposed surfaces comprise said upper surface excluding said first mating surface, said lower surface excluding said second mating surface and said plurality of fastener mating surfaces, and said internal passageway surface of each of said at least one passageway.

2. The improved baffle plate as recited in claim 1, wherein at least one passageway comprises a slot.

3. The improved baffle plate as recited in claim 2, wherein said slot comprises an entrance area and an exit area, wherein said entrance area is larger than said exit area.

4. The improved baffle plate as recited in claim 1, wherein at least one passageway comprises an orifice.

5. The improved baffle plate as recited in claim 1, wherein, said ring further comprises at least one of a plurality of fastening receptors and a plurality of mounting through-holes, coupled to said upper surface and said lower surface of said baffle plate and configured to receive fastening devices in order to couple said baffle plate to said plasma processing system.

6. The improved baffle plate as recited in claim 5, wherein at least one of said plurality of fastening receptors comprises an entrant cavity, an exit through-hole, and an inner receptor surface.

7. The improved baffle plate as recited in claim 6, wherein said inner receptor surface of at least one of said plurality of fastening receptors comprises a first entrant surface, a first lip surface, a second entrant surface, a second lip surface, and an exit surface.

8. The improved baffle plate as recited in claim 7, wherein said plurality of exposed surfaces further comprises said first entrant surface and said first lip surface.

9. The improved baffle plate as recited in claim 1, wherein said baffle plate comprises a metal.

10. The improved baffle plate as recited in claim 9, wherein said metal comprises aluminum.

11. The improved baffle plate as recited in claim 1, wherein said protective barrier comprises a compound containing at least one of a III-column element and a Lanthanon element.

12. The improved baffle plate as recited in claim 11, wherein said III-column element comprises at least one of Yttrium, Scandium, and Lanthanum.

13. The improved baffle plate as recited in claim 11, wherein said Lanthanon element comprises at least one of Cerium, Dysprosium, and Europium.

14. The improved baffle plate as recited in claim 11, wherein said compound comprises at least one of Yttria (Y₂O₃), Sc₂O₃, Sc₂F₃, YF₃, La₂O₃, CeO₂, Eu₂O₃, and DyO₃.

15. The improved baffle plate as recited in claim 1, wherein said protective barrier comprises a minimum thickness and said minimum thickness is constant across at least one of said plurality of exposed surfaces.

16. The improved baffle plate as recited in claim 1, wherein said protective barrier comprises a minimum thickness and said minimum thickness is variable across at least one of said plurality of exposed surfaces.