Low contamination high density plasma etch chambers and methods for making the same

• US 6,394,026 B1
• Filed: 01/19/2000
• Issued: 05/28/2002
• Est. Priority Date: 03/31/1998
• Status: Expired due to Term

• Current Assignee: Lam Research Corporation
• Original Assignee: Lam Research Corporation
• Inventors: Kennedy, William S., Wicker, Thomas E., Maraschin, Robert A.
• Primary Examiner(s): Mills, Gregory
• Assistant Examiner(s): Zervigon, Rudy
• Application Number:
  US09/487,325
• Time in Patent Office: 860 Days
• Field of Search: 118/723 E,728,723 I 156/345 219/121.59,405 438/712,729 361/234 427/577 428/594 376/650,136 216/67
• US Class Current: 156/345.1
• CPC Class Codes: H01J 2237/022 Avoiding or removing foreign or contaminating particles, debris or deposits on sample or tube
• CPC Class Codes: H01J 37/321 the radio frequency energy being inductively coupled to the plasma
• CPC Class Codes: H01J 37/32477 characterised by the means for protecting vessels or internal parts, e.g. coatings
• CPC Class Codes: Y10S 156/914 Differential etching apparatus including particular materials of construction
• CPC Class Codes: Y10S 156/916 Differential etching apparatus including chamber cleaning means or shield for preventing deposits
• CPC Class Codes: Y10T 428/12347 Plural layers discontinuously bonded [e.g., spot-weld, mechanical fastener, etc.]

Abstract

A plasma processing chamber having a chamber liner and a liner support, the liner support including a flexible wall configured to surround an external surface of the chamber liner, the flexible wall being spaced apart from the wall of the chamber liner. The apparatus can include a heater thermally connected to the liner support so as to thermally conduct heat from the liner support to the chamber liner. The liner support can be made from flexible aluminum material and the chamber liner comprises a ceramic material. The flexible wall can include slots which divide the liner support into a plurality of fingers which enable the flexible wall to absorb thermal stresses.

Claims

1. A plasma processing chamber having a chamber liner and a liner support within an interior of the plasma processing chamber, the liner support including a flexible wall configured to surround an external surface of the chamber liner, the flexible wall being spaced apart from the external surface of the chamber liner.

2. A plasma processing chamber as recited in claim 1, further comprising a heater thermally connected to the liner support so as to thermally conduct heat from the liner support to the chamber liner.

3. A plasma processing chamber as recited in claim 1, wherein the liner support is made from flexible aluminum material and the chamber liner comprises a ceramic material.

4. A plasma processing chamber as recited in claim 3, wherein the flexible wall includes slots which divide the liner support into a plurality of fingers which enable the flexible wall to absorb thermal stresses.

5. A plasma processing chamber as recited in claim 4, wherein a lower extension of the liner support is fixed to a lower support section of the chamber liner.

6. A plasma processing chamber as recited in claim 1, further comprising a baffle ring in thermal contact with the chamber liner and the liner support, the baffle ring defining a plasma screen around an electrostatic chuck located in a central portion of the chamber.

7. A plasma processing chamber as recited in claim 6, wherein the baffle ring is made from one or more of silicon carbide (SiC), silicon nitride (Si₃N₄), boron carbide (B₄C), and boron nitride (BN).

8. A plasma processing chamber as recited in claim 1, wherein the chamber liner is made from one or more of silicon carbide (SiC), silicon nitride (Si₃N₄), boron carbide (B₄C), and boron nitride (BN).

9. A plasma processing chamber as recited in claim 1, wherein the chamber liner has low electrical resistivity and is configured to provide an RF path to ground.

10. A plasma processing chamber as recited in claim 1, further comprising a gas distribution plate defined over an electrostatic chuck, the gas distribution plate having high electrical resistivity.

11. A plasma processing chamber as recited in claim 10, wherein the gas distribution plate is made from one or more of silicon carbide (SiC), silicon nitride (Si₃N₄), boron carbide (B₄C), and boron nitride (BN).

12. A plasma processing chamber as recited in claim 1, further comprising a focus ring and a pedestal supporting the focus ring and an electrostatic chuck.

13. A plasma processing chamber as recited in claim 12, wherein the focus ring and the pedestal are made from one or more of silicon carbide (SiC), silicon nitride (Si₃N₄), boron carbide (B₄C), and boron nitride (BN).

14. A plasma processing chamber as recited in claim 1, further comprising a focus ring, a pedestal, and/or a gas distribution plate made from one or more of silicon carbide (SiC), silicon nitride (Si₃N₄), boron carbide (B₄C), and boron nitride (BN).

15. A plasma processing chamber as recited in claim 11, further comprising an RF energy source which inductively couples RF energy through the gas distribution plate and generates a high density plasma in the chamber.

16. A plasma processing chamber as recited in claim 15, wherein the RF energy source comprises a planar antenna.

17. A plasma processing chamber as recited in claim 1, wherein the liner support further includes an outer support thermally connected to a lower extension of the liner support, the outer support being in thermal contact with a water cooled top plate mounted on the chamber.

18. A plasma processing chamber as recited in claim 1, wherein the chamber is a plasma etching chamber.

19. A plasma processing chamber as recited in claim 1, wherein the liner support includes an upper extension, a flexible wall, and a lower extension, wherein the flexible wall and the lower extension have a plurality of slots that define a plurality of fingers in the liner support.

20. A plasma processing chamber as recited in claim 1, wherein a cast heater ring is in thermal contact with the liner support, the heater ring including a resistance heated element which heats the liner support so as to thermally control the temperature of the chamber liner.

21. A plasma processing chamber as recited in claim 1, wherein the chamber liner includes a wafer entry port enabling passage of the wafer into the chamber.

22. A plasma processing chamber as recited in claim 1, wherein the liner support is removably attached to a portion of the chamber.

23. A plasma processing chamber as recited in claim 6, wherein the baffle ring includes openings therein through which gases and by-products are removed from the chamber.

24. A plasma processing chamber as recited in claim 4, wherein the lower extension is bolted to the chamber liner.

25. A plasma processing chamber as recited in claim 1, wherein the flexible wall is separated from an inner periphery of the chamber wall and flexes due to heat deformation towards and away from the chamber wall.

26. A plasma processing chamber as recited in claim 1, wherein the chamber liner is a cylindrical one-piece ceramic liner.

27. A plasma processing chamber as recited in claim 1, wherein the flexible wall includes inner and outer surfaces, the flexible wall being divided into a plurality of fingers by slots extending from the inner surface to the outer surface.

28. A plasma processing chamber having a heater, a ceramic chamber liner and a liner support,

the liner support being within an interior of the plasma processing chamber and including a flexible metal wall configured to surround an external surface of the chamber liner, the flexible metal wall being spaced apart from the chamber liner and the flexible metal wall having a thickness which is less than a thickness of the chamber liner, the flexible metal wall including slots which divide the liner support into a plurality of fingers which enable the flexible metal wall to absorb thermal stresses, and

the heater being thermally connected to the liner support so as to thermally conduct heat from the liner support to the chamber liner.

29. A plasma processing chamber having a heater, a chamber liner, a baffle ring, a focus ring, a gas distribution plate and a liner support,

the liner support being within an interior of the plasma processing chamber and including a flexible metal wall configured to surround an external surface of the chamber liner, the flexible wall including slots which divide the liner support into a plurality of fingers which enable the flexible wall to absorb thermal stresses,

the heater being thermally connected to the liner support so as to thermally conduct heat from the liner support to the chamber liner,

the baffle ring being in thermal contact with the chamber liner and the liner support, the baffle ring defining a plasma screen around an electrostatic chuck located in a central portion of the chamber,

the gas distribution plate having high electrical resistivity, and

the focus ring being located on a pedestal supporting the electrostatic chuck,

the chamber liner, the baffle ring, the focus ring and the gas distribution plate being made from silicon carbide.

30. A plasma processing chamber having a ceramic chamber liner, a ceramic window, an antenna, a gas distribution plate and a liner support,

the liner support being within an interior of the plasma processing chamber and including a flexible metal wall configured to surround an external surface of the chamber liner, the flexible metal wall including slots which divide the liner support into a plurality of fingers which enable the flexible metal wall to absorb thermal stresses,

the gas distribution plate comprising a showerhead through which process gas is supplied to the interior of the plasma processing chamber,

the ceramic window being located between the gas distribution plate and the antenna, the antenna comprising an RF energy source which inductively couples RF energy through the ceramic window and the gas distribution plate so as to generate a high density plasma in the interior of the plasma processing chamber,

the ceramic chamber liner and the gas distribution plate being made from one or more of silicon carbide (SiC), silicon nitride (Si₃N₄), boron carbide (B₄C), and boron nitride (BN).