Methods and apparatus for the optimization of etch resistance in a plasma processing system

• US 20060000797A1
• Filed: 06/30/2004
• Published: 01/05/2006
• Est. Priority Date: 06/30/2004
• Status: Active Grant

• Current Assignee: Lam Research Corporation
• Original Assignee: Lam Research Corporation
• Inventors: Stojakovic, George, Miller, Alan, Adams, Yoko Yamaguchi
• Granted Patent: US 7,316,785 B2
• Time in Patent Office: Days
• US Class Current: 216/37
• CPC Class Codes: H01J 37/32082 Radio frequency generated discharge H01J37/32357, H01J37/32366, H01J37/32394 and H01J37/32403 take precedence
• CPC Class Codes: H01J 37/32862 In situ cleaning of vessels and/or internal parts
• CPC Class Codes: H01L 21/3065 Plasma etching; Reactive-ion etching

Abstract

In a plasma processing system, including a plasma processing chamber, a method of optimizing the etch resistance of a substrate material is described. The method includes flowing pre-coat gas mixture into the plasma processing chamber, wherein the pre-coat gas mixture has an affinity for a etchant gas flow mixture; striking a first plasma from the pre-coat gas mixture; and introducing a substrate comprising the substrate material. The method also includes flowing the etchant gas mixture into the plasma processing chamber; striking a second plasma from the etchant gas mixture; and etching the substrate with the second plasma. Wherein the first plasma creates a pre-coat residual on a set of exposed surfaces in the plasma processing chamber, and the etch resistance of the substrate material is maintained.

Claims

1. In a plasma processing system, including a plasma processing chamber, a method of optimizing the etch resistance of a substrate material, comprising the steps of:

flowing pre-coat gas mixture into the plasma processing chamber, wherein said pre-coat gas mixture has an affinity for an etchant gas mixture;

striking a first plasma from said pre-coat gas mixture;

introducing a substrate comprising said substrate material;

flowing said etchant gas mixture into said plasma processing chamber;

striking a second plasma from said etchant gas mixture;

etching said substrate with said second plasma;

wherein said first plasma creates a pre-coat residual on a set of exposed surfaces in said plasma processing chamber, and said etch resistance of said substrate material is substantially maintained.

2. The method of claim 1, further including the step of cleaning the plasma processing chamber using a waferless chamber cleaning process, prior to said flowing pre-coat step.

3. The method of claim 1, wherein said etchant gas mixture further includes etchant species.

4. The method of claim 3, wherein said pre-coat residual chemically interacts with said etchant species to create a passivation species.

5. The method of claim 4, wherein said passivation species coats said substrate material.

6. The method of claim 1, wherein said substrate material is comprised of photoresist.

7. The method of claim 1, wherein said substrate material is comprised of BARC.

8. The method of claim 1, wherein said substrate material is comprised of an inorganic material.

9. The method of claim 1, wherein said substrate material is comprised of silicon.

10. The method of claim 1, wherein said pre-coat gas mixture comprises O₂.

11. The method of claim 1, wherein said pre-coat gas mixture comprises HBr.

12. The method of claim 1, wherein said precoat gas mixture comprises Cl₂.

13. The method of claim 1, wherein said pre-coat gas mixture comprises He.

14. The method of claim 1, wherein said pre-coat gas mixture comprises N₂.

15. The method of claim 1, wherein said pre-coat gas mixture comprises Ar.

16. The method of claim 1, wherein said pre-coat gas mixture comprises CF₄.

17. The method of claim 1, wherein said pre-coat gas mixture comprises CH₂F₂.

18. The method of claim 1, wherein said pre-coat gas mixture comprises CHF₃.

19. The method of claim 1, wherein said pre-coat gas mixture comprises CH_xF_y, where.x and y are integers.

20. The method of claim 1, wherein said pre-coat gas mixture comprises SiCl₄.

21. The method of claim 1, wherein said pre-coat gas mixture comprises SF₆.

22. The method of claim 1, wherein said pre-coat gas mixture comprises NF₃.

23. The method of claim 1, wherein said substrate is semiconductor wafer.

24. The method of claim 1, wherein said substrate is a glass panel.

25. In a plasma processing system, including a plasma processing chamber, a method of optimizing the etch resistance of a substrate material, comprising the steps of:

cleaning the plasma processing chamber using a waferless chamber cleaning process;

flowing pre-coat gas mixture into the plasma processing chamber, wherein said pre-coat gas mixture has an affinity for a etchant gas flow mixture;

striking a first plasma from said pre-coat gas mixture;

introducing a substrate comprising said substrate material;

flowing said etchant gas mixture into said plasma processing chamber;

striking a second plasma from said etchant gas mixture;

etching said substrate with said second plasma;

wherein said first plasma creates a passivation species on a set of exposed surfaces in said plasma processing chamber, and said etch resistance of said substrate material is substantially maintained.