Method for conditioning a plasma etch chamber

• US 6,322,716 B1
• Filed: 08/30/1999
• Issued: 11/27/2001
• Est. Priority Date: 08/30/1999
• Status: Expired due to Fees

• Current Assignee: Cypress Semiconductor Corporation (Infineon Technologies AG)
• Original Assignee: Cypress Semiconductor Corporation (Infineon Technologies AG)
• Inventors: Qiao, Jianmin, Thekdi, Sanjay
• Primary Examiner(s): DANG, THI D
• Application Number:
  US09/385,187
• Time in Patent Office: 820 Days
• Field of Search: 216/67, 438/905, 134/1.1
• US Class Current: 216/67
• CPC Class Codes: H01J 37/321 the radio frequency energy being inductively coupled to the plasma
• CPC Class Codes: H01J 37/32862 In situ cleaning of vessels and/or internal parts
• CPC Class Codes: Y10S 438/905 Cleaning of reaction chamber

Abstract

A method for conditioning a plasma etch chamber is presented. A plasma etch chamber is provided, which preferably includes a chuck for supporting a topography. A conditioning process may be performed in the etch chamber. The conditioning process preferably includes positioning a cover topography on or above the chuck. A conditioning feed gas containing (hydro)halocarbons may be introduced into the chamber. A conditioning plasma may be generated from the conditioning feed gas for a conditioning time. Immediately after generating the conditioning plasma is complete, the overall thickness of the cover topography is preferably at least as great as immediately before generating the conditioning plasma. By performing a conditioning process in such a manner, the total cost and complexity of the conditioning process may be reduced.

Claims

1. A method for conditioning a plasma etch chamber, comprising:

positioning a cover topography on or over a chuck in the chamber; and

generating a conditioning plasma from a conditioning feed gas comprising one or more (hydro)halocarbons for a conditioning time, wherein an overall thickness of the cover topography immediately after generating said conditioning plasma is at least as great as immediately before generating said conditioning plasma.

2. The method of claim 1, wherein the overall thickness of the cover topography is greater immediately after generating said conditioning plasma than immediately before generating said conditioning plasma.

3. The method of claim 2, wherein said generating said conditioning plasma for a conditioning time comprises depositing polymeric material on the surface of the cover topography.

4. The method of claim 2, wherein a deposition rate of said depositing polymeric material is less than 3 angstroms per minute.

5. The method of claim 1, wherein the conditioning feed gas comprises an etching component and a polymer-forming component, and wherein the etching component comprises a first (hydro)fluorocarbon and the polymer-forming component comprises a second (hydro)fluorocarbon.

6. The method of claim 5, wherein the second (hydro)fluorocarbon comprises a compound of the formula C_xH_yF_z, wherein x is from 1 to 5, y is from 0 to 8, and z is from 2 to (2x+2−

y).

7. The method of claim 5, wherein the second (hydro)fluorocarbon has a F/C ratio of about 2.

8. The method of claim 1, wherein the cover topography comprises a dummy topography.

9. The method of claim 8, wherein the cover topography further comprises a single-crystal silicon substrate.

10. The method of claim 9, wherein the cover topography further comprises an oxide layer overlying the substrate.

11. The method of claim 1, wherein said conditioning time is from about 0.5 minutes to about 10 minutes.

12. A method for conditioning a plasma etch chamber, comprising:

positioning a cover topography on or over a chuck in the plasma etch chamber; and

generating a conditioning plasma from a conditioning feed gas comprising an etching component and a polymer-forming component for a time sufficient to deposit polymeric material on the upper surface of the cover topography, wherein a deposition rate of said depositing polymeric material is at least as great as a rate at which said conditioning plasma etches the upper surface of said cover topography.

13. The method of claim 12, wherein said depositing said polymeric material comprises forming a layer of polymeric material across the cover topography, wherein the layer of polymeric material inhibits or prevents the conditioning plasma from etching underlying materials.

14. The method of claim 12, wherein said generating said conditioning plasma comprises depositing polymeric material on one or more inner surfaces of the chamber.

15. The method of claim 13, wherein the polymer-forming species comprises a compound of the formula C₂H₂F₄.

16. The method of claim 12, wherein the etching component comprises a first (hydro)fluorocarbon and the polymer-forming component comprises a second (hydro)fluorocarbon.

17. The method of claim 16, wherein the second (hydro)fluorocarbon has a F/C ratio of about 2.

18. A method for operating a plasma etch chamber, comprising:

generating a conditioning plasma from a conditioning feed gas for a conditioning time in the plasma etch chamber, wherein the plasma etch chamber contains a cover topography on a chuck, and the conditioning feed gas comprises a polymer-forming (hydro)halocarbon component and an etching component;

removing the cover topography from the chuck;

etching a substrate in the plasma etch chamber after generating said conditioning plasma.

19. The method of claim 18, wherein at least one etching component of the conditioning feed gas is substantially the same as an etching component of the etching feed gas.

20. The method of claim 19, wherein said etching comprises generating an etching plasma from an etching feed gas comprising a polymer-forming component and an etching component, and wherein the volume percentage of the polymer-forming component within the conditioning feed gas is higher than the volume percentage of the polymer-forming component within the etching feed gas.