Plasma cleaning of deposition chamber residues using duo-step wafer-less auto clean method

• US 7,028,696 B2
• Filed: 05/03/2002
• Issued: 04/18/2006
• Est. Priority Date: 05/04/2001
• Status: Active Grant

• Current Assignee: Lam Research Corporation
• Original Assignee: Lam Research Corporation
• Inventors: Wong, Vincent, Richardson, Brett C.
• Primary Examiner(s): Markoff, Alexander
• Application Number:
  US10/139,042
• Publication Number:
  US 20030000546A1
• Time in Patent Office: 1,446 Days
• Field of Search: 134/1, 134/1.1, 134/22.1, 134/22.18, 134/26, 134/30, 438/905
• US Class Current: 134/1.1
• CPC Class Codes: B08B 3/06 using perforated drums in which the article or material is placed B08B3/042 takes precedence
• CPC Class Codes: B08B 7/0035 by radiant energy, e.g. UV, laser, light beam or the like
• CPC Class Codes: C23C 16/4405 Cleaning of reactor or parts inside the reactor by using reactive gases
• CPC Class Codes: H01J 37/32862 In situ cleaning of vessels and/or internal parts
• CPC Class Codes: H01J 37/32935 Monitoring and controlling tubes by information coming from the object and/or discharge
• CPC Class Codes: H01J 37/32963 End-point detection
• CPC Class Codes: Y10S 438/905 Cleaning of reaction chamber

Abstract

A method involving plasma cleaning of deposit residues in process chamber using duo-step wafer-less auto clean method is detailed. Specifically, the method involves cleaning the processing chamber by flowing a first gaseous composition with at least about 75% of fluorine-containing compound of the formula X_yF_z, into a processing chamber and then forming a first etchant plasma which removes silicon and silicon based byproducts from the interior surfaces of the processing chamber. The method then involves flowing a second gaseous composition into the processing chamber with a composition of at least about 50% O₂ and forming a plasma from the second gaseous composition to provide a second etchant plasma which removes carbon and carbon based byproducts from the interior surfaces of the processing chamber. A system configured to execute the two step cleaning process is also provided.

Claims

1. A method for cleaning a processing chamber comprising:

flowing a first gaseous composition into a processing chamber, the first gaseous composition including at least about 75% of a fluorine-containing compound of the formula X_yF_z;

forming a plasma from the first gaseous composition to provide a first etchant plasma which removes silicon and silicon based compounds from interior surfaces of the processing chamber;

flowing a second gaseous composition into a processing chamber after removal of the first gaseous composition, the second gaseous composition including at least about 50% O₂; and

forming a plasma from the second gaseous composition to provide a second etchant plasma which removes carbon and carbon based compounds from interior surfaces of the processing chamber.

2. A method for cleaning a processing chamber as recited in claim 1 wherein said fluorine-containing compound is selected from the group consisting essentially of NF₃ and SF₆.

3. A method for cleaning a processing chamber as recited in claim 2 wherein said fluorine-containing compound is SF₆.

4. A method for cleaning a processing chamber as recited in claim 2 wherein said first gaseous composition is at least about 90% of said fluorine-containing compound.

5. A method for cleaning a processing chamber as recited in claim 4 wherein said first gaseous composition essentially consists of said fluorine-containing compound.

6. A method for cleaning a processing chamber as recited in claim 1 wherein said second gaseous composition is at least about 75% O₂.

7. A method for cleaning a processing chamber as recited in claim 6 wherein said second gaseous composition is at least about 90% O₂.

8. A method for cleaning a processing chamber as recited in claim 6 wherein said second gaseous composition includes a fluorine-containing compound of the formula X_yF_z.

9. A method for cleaning a processing chamber as recited in claim 8 wherein said fluorine-containing compound of said second gaseous composition is selected from the group consisting essentially of NF₃ and SF₆.

10. A method for cleaning a processing chamber as recited in claim 8 wherein said fluorine-containing compound of said second gaseous composition is SF₆.

11. A method for cleaning a processing chamber as recited in claim 10 wherein said second gaseous composition is about 90% O₂ and 10% SF₆.

12. A method for cleaning a processing chamber as recited in claim 6 wherein said second gaseous composition essentially consists of O₂.

13. A method for processing wafers comprising:

first cleaning interior surfaces of a process chamber with a fluoride plasma including at least about 75% of a fluorine-containing compound of the formula X_yF_z, said fluoride plasma being optimized to remove silicon and silicon compounds;

second cleaning said interior surfaces of said process chamber with an oxygen plasma including at least about 50% O₂, said oxygen plasma being optimized to remove carbon and carbon compounds; and

processing a wafer within said process chamber after said first cleaning and said second cleaning.

14. A method for cleaning a processing chamber as recited in claim 13 wherein said fluorine-containing compound is selected from the group consisting essentially of NF₃ and SF₆.

15. A method for cleaning a processing chamber as recited in claim 14 wherein the first cleaning lasts for about 17 seconds and the second cleaning lasts for about 6 seconds.

16. A method for cleaning a processing chamber as recited in claim 14 wherein the method operation of first cleaning interior surfaces of a process chamber with a fluoride plasma further includes:

maintaining a chamber pressure between about 2 milliTorr and 5 milliTorr;

applying a TCP power of about 1000 watts;

introducing the fluoride containing compound into the processing chamber at a flow rate between about 50 standard cubic centimeters per minute (sccm) and about 40 sccm.

17. A method for cleaning a processing chamber as recited in claim 15 wherein said first gaseous composition essentially consists of said fluorine-containing compound.

18. A method for cleaning a processing chamber as recited in claim 13 wherein said second gaseous composition is at least about 75% O₂.

19. A method for cleaning a processing chamber as recited in claim 18 wherein said second gaseous composition is at least about 90% O₂.

20. A method for cleaning a processing chamber as recited in claim 19 wherein said second gaseous composition includes a fluorine-containing compound of the formula X_yF_z.

21. A method for cleaning a processing chamber as recited in claim 20 wherein said fluorine-containing compound of said second gaseous composition is selected from the group consisting essentially of NF₃ and SF₆.

22. A method for cleaning a processing chamber as recited in claim 21 wherein said fluorine-containing compound of said second gaseous composition is SF₆.

23. A method for cleaning a processing chamber as recited in claim 22 wherein said second gaseous composition is about 90% O₂ and 10% SF₆.

24. A method for cleaning a processing chamber as recited in claim 23 wherein said second gaseous composition essentially consists of O₂.

25. A method for cleaning interior surfaces of a processing chamber, comprising:

flowing a first etchant process gas with a fluorine-containing compound of the formula X_yF_z, said fluorine-containing compound being optimized to remove silicon and silicon compounds;

forming a plasma from said first etchant process gas;

flowing a second etchant process gas containing oxygen upon removal of the first etchant gas, said process gas being optimized to remove carbon based compounds and an optional fluorine-containing compound of the formula X_xF_z, said fluorine-containing compound being optimized to remove silicon and silicon compounds;

forming a plasma from said second etchant process gas;

maintaining a pressure in the processing chamber between about 2 mTorr and about 100 mTorr; and

monitoring said process for carbon-based compounds on interior surfaces of said processing chamber for reaching a predetermined level.

26. A method for cleaning interior surfaces of a processing chamber as recited in claim 25 wherein said optional fluorine containing compound is selected from the group consisting essentially of NF₃ and SF₆.

27. A method for cleaning interior surfaces of a processing chamber as recited in claim 25 wherein the second etchant process gas is essentially oxygen and a flow rate of the process gas is about 100 standard cubic centimeters per minute.

28. A method for cleaning interior surfaces of a processing chamber as recited in claim 25, further including:

introducing the second etchant process gas containing oxygen into the processing chamber at a flow rate between about 100 standard cubic centimeters per minute (sccm) and about 600 sccm; and

applying a TCP power between about 800 Watts and 1500 Watts.

29. A method for cleaning interior surfaces of a processing chamber as recited in claim 28 wherein said second etchant process gas containing oxygen is at least about 90% O₂.