Method and apparatus for an improved optical window deposition shield in a plasma processing system

• US 7,163,585 B2
• Filed: 03/19/2004
• Issued: 01/16/2007
• 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, Takase, Taira, Saigusa, Hidehito
• Primary Examiner(s): Hassanzadeh; Parviz
• Assistant Examiner(s): DHINGRA, RAKESH KUMAR
• Application Number:
  US10/803,994
• Publication Number:
  US 20040173155A1
• Time in Patent Office: 1,033 Days
• Field of Search: 156/345.25, 118/715
• US Class Current: 118/715
• CPC Class Codes: H01J 37/32458 Vessel
• CPC Class Codes: H01J 37/32495 Means for protecting the vessel against plasma
• CPC Class Codes: H01J 37/32972 Spectral analysis
• CPC Class Codes: H01L 21/67069 for drying etching

Abstract

The present invention presents an improved optical window deposition shield for optical access to a process space in a plasma processing system through a deposition shield, wherein the design and fabrication of the optical window deposition shield advantageously provides an optically clean access to the processing plasma in the process space while sustaining substantially minimal erosion of the optical window deposition shield.

Claims

1. An insert for a deposition shield in a plasma processing system comprising:

a plug configured to fit into an opening in said deposition shield, said plug comprises a frontal surface and a perimeter surface;

a flange coupled to said plug and configured to couple said insert to at least one of the deposition shield and a chamber wall of the plasma processing system, said flange comprising a first surface, a second surface, and an edge surface, wherein said first surface comprises;

a mating surface extending inward from said edge surface, and

a recess positioned between said mating surface and said perimeter surface of

said plug, said recess having a recess surface recessed from said mating surface; and

a protective barrier provided on a plurality of exposed surfaces of said insert, wherein the plurality of exposed surfaces comprise said frontal surface of said plug, said perimeter surface of said plug, and said first surface of said flange excluding said mating surface.

2. The insert as recited in claim 1, wherein said insert comprises a plurality of fastening receptors coupled to said first surface of said flange and said second surface of said flange and configured to receive fastening devices in order to couple said insert to the at least one of the deposition shield and the chamber wall.

3. The insert as recited in claim 2, wherein each of said plurality of fastening receptors comprises an entrant region, an entrant cavity, an exit through-hole, an interior fastener surface, and a recessed fastener surface.

4. The insert as recited in claim 3, wherein said plurality of exposed surfaces, having said protective barrier thereon, further comprise said interior fastener surface.

5. The insert as recited in claim 1, wherein said plurality of exposed surfaces, having said protective barrier thereon, further comprises said recess surface.

6. The insert as recited in claim 1, wherein said insert comprises a metal.

7. The insert as recited in claim 6, wherein said metal comprises aluminum.

8. The insert as recited in claim 1, wherein said insert comprises a rectangular shape.

9. The insert as recited in claim 1, wherein said protective barrier comprises Al₂O₃.

10. The insert as recited in claim 1, wherein said protective barrier comprises a mixture of Al₂O₃ and Y₂O₃.

11. The insert as recited in claim 1, wherein said protective baffler comprises a compound containing at least one of a group III element or a Lanthanon element.

12. The insert as recited in claim 11, wherein said group III element comprises at least one of Yttrium, Scandium, and Lanthanum.

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

14. The insert as recited in claim 1, wherein said protective barrier comprises at least one of Yttria (Y₂O₃), Sc₂O₃, Sc₂F₃, YF₃, La₂O₃, CeO₂, Eu₂O₃, and DyO₃.

15. The insert as recited in claim 1, wherein said protective barrier comprises a predetermined thickness and said predetermined thickness is constant across at Least one of said exposed surfaces.

16. The insert as recited in claim 1, wherein said protective barrier comprises a variable thickness and said variable thickness ranging from 0.5 to 500 microns.

17. The insert of claim 1, wherein said protective barrier is provided on at least a portion of said recess.

18. The insert of claim 17, wherein said protective barrier is provided on only a portion of said recess.

19. The insert as recited in claim 1, wherein said recess comprises:

a first sidewall extending from said mating surface to said recess surface, said first sidewall being substantially at right angles to said mating surface and said recess surface; and

a second sidewall opposing said first sidewall and extending from said recess surface to said perimeter surface of said plug, said second sidewall being substantially at a right angle to said recess surface, wherein said second sidewall and said recess have said protective barrier provided thereon.

20. The insert as recited in claim 1, wherein said protective barrier includes a coating which comprises Yttria.

21. The insert as recited in claim 20, wherein said coating is a spray coating.

22. The insert as recited in claim 20, wherein said first sidewall does not include said protective barrier thereon.

23. The insert as recited in claim 1, wherein:

said mating surface is a bare metal surface not having said protective barrier thereon and not having an anodized layer thereon; and

said insert further comprises at least one surface having an anodized layer thereon.

24. The insert as recited in claim 1, wherein said protective barrier is provided in direct contact with a bare surface of said insert not having an anodization layer thereon.