Backflush chamber clean

• US 20040200499A1
• Filed: 04/11/2003
• Published: 10/14/2004
• Est. Priority Date: 04/11/2003
• Status: Active Grant

• Current Assignee: Applied Materials Incorporated
• Original Assignee: Applied Materials Incorporated
• Inventors: Janakiraman, Karthik, Floyd, Kirby, Harvey, Keith
• Granted Patent: US 7,037,376 B2
• Time in Patent Office: Days
• US Class Current: 134/1.1
• 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: C23C 16/455 characterised by the method used for introducing gases into reaction chamber or for modifying gas flows in reaction chamber

Abstract

A processing chamber may be effectively cleaned by a remote plasma flowed through the chamber in a direction opposite to the direction of gas flowed during wafer processing. Specifically, the remotely generated plasma may be introduced directly into the chamber through a processing gas exhaust or other port, and then be exhausted from the chamber by traveling through the gas distribution shower head to the foreline. In one embodiment of the present invention, this reverse flow of remote cleaning plasma is maintained for the duration of the chamber cleaning step. In an alternative embodiment, the direction of flow of the remote cleaning plasma through the chamber is alternated between this reverse flow and a conventional forward flow.

Claims

1. A method of cleaning a substrate processing chamber having a gas distribution showerhead adapted to release one or more processing gases into an interior substrate processing region of the chamber during a substrate processing operation, the method comprising:

generating reactive species suitable for removing unwanted material deposits from an interior of the chamber; and

flowing the reactive species from the interior substrate processing region through the gas distribution showerhead.

2. The method of claim 1 wherein the reactive species are generated in a chamber remote from the substrate processing chamber.

3. The method of claim 1 wherein the reactive species are flowed into the substrate processing chamber through a first valve, and the reactive species are flowed from the substrate processing chamber through the gas distribution showerhead to a chamber exhaust through a second valve.

4. The method of claim 1 wherein the reactive species are flowed from the interior substrate processing region through the gas distribution showerhead at a first time, and the reactive species are flowed into the interior substrate processing region through the gas distribution showerhead at a second time.

5. The method of claim 4 wherein:

at the first time the reactive species are flowed into the substrate processing chamber through a first valve and a second valve and the reactive species are flowed from the substrate processing chamber through the gas distribution showerhead to a chamber exhaust through a third valve; and

at the second time the reactive species are flowed into the substrate processing chamber through the first valve and the third valve and the reactive species are flowed from the substrate processing chamber to a chamber exhaust through the second valve.

6. A method of cleaning a substrate processing chamber comprising:

generating in a remote chamber reactive species suitable for cleaning unwanted material deposits in the processing chamber;

flowing the reactive species, in order, from the remote plasma chamber through a gas distribution showerhead into the substrate processing chamber and then through an exhaust line during a first time period; and

flowing the reactive species, in order, from the remote plasma chamber into the substrate processing chamber, through the gas distribution showerhead and then through an exhaust line during a second time period.

7. The method of claim 6 wherein the second time period occurs prior to the first time period.

8. A method of cleaning a processing chamber comprising:

generating a cleaning plasma containing a reactive ionic species;

flowing the generated cleaning plasma into the processing chamber through an inlet port different from a processing gas distribution showerhead utilized to flow a processing gas to a substrate within the chamber, and

exhausting the remotely generated plasma from the processing chamber through the processing gas distribution showerhead.

9. The method of claim 8 further comprising:

changing a flow direction of the remotely generated plasma to cause the remotely generated plasma to enter the processing chamber through the gas distribution showerhead, and to cause the remotely generated plasma to be exhausted from the chamber through an exhaust port.

10. A method of cleaning a processing chamber comprising flowing a remotely generated cleaning plasma into the processing chamber through other than a gas distribution faceplate ordinarily utilized to flow processing gases into the chamber, such that the flowed plasma avoids a substantial pressure increase associated with flow through the gas distribution faceplate, thereby enhancing a concentration of reactive ionic species available to react with and clean the processing chamber.

11. A substrate processing system comprising:

a housing defining a process chamber;

a substrate support for supporting a substrate within the chamber;

a processing gas source;

a remote plasma generator;

a gas distribution showerhead positioned proximate to the substrate support,

a foreline configured to receive exhaust from the chamber; and

a gas delivery system in selective fluid communication with the processing gas source, the remote plasma source, the gas distribution showerhead, and the foreline, the gas delivery system configurable to flow processing gas from the processing gas source into the chamber through the gas distribution showerhead during processing of a substrate within the chamber, and configurable to flow cleaning plasma from the chamber into the foreline through the gas distribution showerhead during removal of residue from the chamber.

12. The substrate processing system of claim 11 wherein the gas delivery system comprises:

a first valve selectively operable to a first configuration to place the remote plasma source in fluid communication with the chamber; and

a second valve selectively operable to a first configuration to place the gas distribution showerhead in fluid communication with the foreline.

13. The substrate processing system of claim 12 wherein the first valve and the second valve comprise three-way valves having “

T”

-shaped orifices.

14. The substrate processing system of claim 12 wherein:

the first valve is selectively operable between the first configuration and a second configuration to place the chamber in fluid communication with the second valve; and

the second valve is selectively operable between the first configuration and a second configuration to place the first valve in fluid communication with the foreline.

15. The substrate processing system of claim 14 wherein the first valve is in selective fluid communication with the chamber through a port utilized to exhaust process gases from the chamber during processing of a semiconductor substrate within the chamber.

16. The substrate processing system of claim 14 wherein the first valve is in selective fluid communication with the chamber through a cleaning gas inlet port distinct from a processing gas exhaust port.

17. The substrate processing system of claim 14 further comprising a third valve selectively operable between a first configuration to place the first valve in fluid communication with the chamber, and a second configuration to place the chamber in fluid communication with the foreline through a bypass line.

18. The substrate processing system of claim 17 wherein the third valve comprises a three-way valve having a “

T”

-shaped orifice.

19. The substrate processing system of claim 17 further comprising a controller in communication with the first, second, and third valves, the controller operable to configure the first, second, and third valves in the first configuration during a chamber cleaning process, and to configure the first, second, and third valves in the second configuration during processing of a substrate within the chamber.

20. The substrate processing system of claim 17 wherein the third valve is in selective fluid communication with the chamber through a port utilized to exhaust process gases from the chamber during processing of a semiconductor substrate within the chamber.

21. The substrate processing system of claim 17 wherein the third valve is in selective fluid communication with the chamber through a cleaning gas inlet port distinct from a processing gas exhaust port.

22. A valve network governing flow of a remotely generated plasma to a processing chamber, the valve network comprising:

a first valve selectively operable to a first configuration to place a remote plasma source in fluid communication with the chamber; and

a second valve selectively operable to a first configuration to place a gas distribution showerhead within the chamber in fluid communication with a chamber foreline.

23. The valve network of claim 22 wherein the first valve and the second valve comprise three-way valves having “

T”

-shaped orifices.

24. The valve network of claim 22 wherein:

the first valve is selectively operable between the first configuration and a second configuration to place the chamber in fluid communication with the second valve; and

the second valve is selectively operable between the first configuration and a second configuration to place the first valve in fluid communication with the foreline.

25. The valve network of claim 22 further comprising a third valve selectively operable between a first configuration to place the first valve in fluid communication with the chamber, and a second configuration to place the chamber in fluid communication with the chamber foreline through a bypass line.

26. The valve network of claim 25 wherein the third valve comprises a three-way valve having a “

T”

-shaped orifice.

27. The valve network of claim 25 further comprising a controller in communication with the first, second, and third valves, the controller operable to configure the first, second, and third valves in the first configuration during a chamber cleaning process, and to configure the first, second, and third valves in the second configuration during processing of a substrate within the chamber.