Tandem etch chamber plasma processing system

• US 6,962,644 B2
• Filed: 09/10/2002
• Issued: 11/08/2005
• Est. Priority Date: 03/18/2002
• Status: Expired due to Term

• Current Assignee: Applied Materials Incorporated
• Original Assignee: Applied Materials Incorporated
• Inventors: McChesney, Jon, Todorov, Valentin N., Schneider, Gerhard M., Barnes, Michael S., Palagashvili, David, Holland, John P., Paterson, Alexander
• Primary Examiner(s): Hassanzadeh, Parviz
• Assistant Examiner(s): Moore, Karla
• Application Number:
  US10/241,653
• Publication Number:
  US 20030176074A1
• Time in Patent Office: 1,155 Days
• Field of Search: 156/345.31, 156/345.28, 156/345.32, 118/719, 438/689, 438/710, 438/716
• US Class Current: 156/345.28
• 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 37/32458 Vessel
• CPC Class Codes: H01L 21/67069 for drying etching

Abstract

A method and apparatus for processing wafers including a chamber defining a plurality of isolated processing regions. The isolated processing regions have an upper end and a lower end. The chamber further includes a plurality of plasma generation devices each disposed adjacent the upper end of each isolated processing region, and one of a plurality of power supplies connected to each plasma generation device. The output frequency of the plurality of power supplies are phase and/or frequency locked together. Additionally, the chamber includes a plurality of gas distribution assemblies. Each gas distribution assembly is disposed within each isolated processing region. A movable wafer support is disposed within each isolated processing region to support a wafer for plasma processing thereon. The movable wafer support includes a bias electrode coupled to a bias power supply configured to control the bombardment of plasma ions toward the movable wafer support.

Claims

1. An apparatus for processing a wafer, comprising:

a chamber defining a plurality of isolated processing regions, each having an upper end and a lower end;

a plurality of plasma generation devices, each being disposed adjacent the upper end of one isolated processing region;

a plurality of RF power supplies, each being connected to one plasma generation device, wherein the output signals of the RF power supplies are locked together by at least one of a phase lock and a frequency lock;

a plurality of gas distribution assemblies, each being coupled to one plasma generation device and disposed within one isolated processing region; and

a plurality of movable wafer supports, each being disposed within one isolated processing region, wherein each movable wafer support includes a bias electrode coupled to a bias power supply.

2. The apparatus of claim 1, further comprising an RF shield member positioned between a first plasma generation device disposed adjacent a first isolated processing region and a second plasma generation device disposed adjacent a second isolated processing region, the RF shield member being configured to electro-magnetically isolate the first plasma generation device from the second plasma generation device.

4. The apparatus of claim 1, wherein the movable wafer support comprises an outer shell and an insulator disposed thereon to support the bias electrode.

5. The apparatus of claim 1, wherein the plasma generation device includes a thermal cooling plate adapted to remove heat therefrom.

6. The apparatus of claim 5, wherein the thermal cooling plate is adapted to maintain the temperature of the plasma generation device to about +/−

5 degrees Celsius.

7. The apparatus of claim 1, wherein the plurality of isolated processing regions are connected by a common vacuum source.

8. The apparatus of claim 7, wherein the isolated processing regions are connected to a plenum adapted to equalize chamber pressure between the plurality of isolated processing regions.

9. The apparatus of claim 1, further comprising a skirt member coupled to the movable wafer support.

10. The apparatus of claim 9, wherein the skirt member is adapted to move in conjunction with the movable wafer support to form a plasma barrier between the upper end and lower end of the isolated processing region.

11. The apparatus of claim 9, wherein the skirt member includes a plurality of apertures to allow process gasses to flow therethrough.

12. The apparatus of claim 1, further comprising a gas flow splitting apparatus adapted to split the flow of one or more process gasses about equally between each isolated processing region.

13. The apparatus of claim 12, wherein the gas flow splitting apparatus comprises at least one restive element adapted to provide an about equal gas flow to each of the plurality of isolated processing regions.

14. The apparatus of claim 12, wherein the gas flow splitting apparatus comprises at least one gas flow controller adapted to provide an about equal gas flow to each of the plurality of isolated processing regions.

15. The apparatus of claim 14, wherein the gas flow splitting apparatus comprises a gas flow meter, wherein the gas flow controller is fluidly coupled to a first gas path, wherein the gas flow meter and the gas flow controller are configured to control the gas flow between each of the plurality of isolated processing region.

16. The apparatus of claim 1, further comprising a process analysis system.

17. The apparatus of claim 16, wherein the process analysis system comprises an optical detector optically coupled to each processing region to receive optical signals therefrom.

18. The apparatus of claim 1 wherein each of the plasma generation devices comprises at least one of an electrode, a coil, and a toroidal plasma generation conduit.

3. An apparatus for processing a wafer, comprising:

a chamber defining a plurality of isolated processing regions, each having an upper end and a lower end;

a plurality of plasma generation devices, each being disposed adjacent the upper end of one isolated processing region;

a plurality of RF power supplies, each being connected to one plasma generation device, wherein the output signals of the RF power supplies are locked together;

a plurality of gas distribution assemblies, each being coupled to one plasma generation device and disposed within one isolated processing region;

a plurality of movable wafer supports, each being disposed within one isolated processing region, wherein each movable wafer support includes a bias electrode coupled to a bias power supply; and

an RF power supply controller coupled to the plurality of RF power supplies, wherein the RF power supply controller is configured to lock the output frequency of each of the RF power supplies using at least one of a phase lock and a frequency lock.

19. A tandem etching chamber, comprising:

a first tandem processing chamber defining a first processing region, comprising;

a first movable wafer support positioned in the first tandem processing chamber; and

a first gas distribution assembly disposed at an upper end of the first processing region;

a second tandem processing chamber positioned adjacent the first tandem processing chamber, the second tandem processing chamber defining a second processing region that is isolated therefrom by a shared interior wall, the second tandem processing chamber comprising;

a second movable wafer support positioned in the second tandem chamber;

a second gas distribution assembly disposed at an upper end of the second processing region; and

a pumping apparatus cooperatively in fluid communication with the first and second tandem processing chambers;

a first plasma generation device in communication with the first tandem processing chamber and a second plasma generation device in communication with the second tandem processing chamber, wherein a first signal driving the first plasma generation device is frequency or phase locked with a second signal driving the second plasma generation device;

an RF shield member positioned between the first and second plasma generation devices; and

a gas splitting apparatus coupled to the first and second gas distribution assemblies, wherein the gas splitting apparatus is adapted to about evenly divide an input gas flow between the first and second gas distribution assemblies.

20. The tandem chamber of claim 19, further comprising a first electrical bias source coupled to the first movable wafer support.

21. The tandem chamber of claim 19, further comprising a second electrical bias source coupled to the second movable wafer support.

22. The tandem chamber of claim 19, wherein the first and second plasma generation devices comprise a first and second RF source.

23. The tandem chamber of claim 19, further comprising a first skirt member coupled to the first movable wafer support and a second skirt member coupled to the second movable wafer support.

24. The tandem chamber of claim 23, wherein each of the first and second skirt members provide a plasma shield between respective first and second processing regions and a respective adjacent portion in fluid communication with the first and second tandem processing chambers.

25. The tandem chamber of claim 19, wherein the shared interior wall separates an upper portion of the respective first and second tandem processing chambers, while allowing an adjacent portion of the respective first and second tandem processing chambers to be in fluid communication with each other.

26. The tandem chamber of claim 25, wherein the adjacent portion is defined by a plenum positioned with respect to the first and second plasma generation devices to minimize plasma generation within the adjacent portion.

27. The tandem chamber of claim 19, wherein the first and second plasma generation devices comprise at least one of an electrode, a coil, and a toroidal plasma generation circuit.

28. An etch processing system, comprising:

a loadlock chamber;

a wafer transfer chamber selectively in communication with the loadlock chamber; and

at least one tandem etch processing chamber selectively in communication with the wafer transfer chamber, the tandem etch chamber comprising;

a first and second adjacently positioned processing chambers;

a first and second gas distribution assembly in fluid communication with the first and second processing chambers, respectively;

a first plasma generation device in communication with the first adjacently positioned processing chamber and a second plasma generation device in communication with the second adjacently positioned processing chamber, wherein a first signal driving the first plasma generation device is frequency or phase locked to a second signal driving the second plasma generation device, and wherein the first and second adjacently positioned processing chambers share a common wall that process separates the respective processing chambers while allowing fluid communication therebetween; and

a gas splitting apparatus coupled to the first and second gas distribution assemblies, wherein the gas splitting apparatus is adapted to about evenly divide an input gas flow between the first and second gas distribution assemblies.

29. The system of claim 28, wherein the wafer transfer chamber includes a wafer transfer robot positioned therein, the wafer transfer robot being configured to transfer wafers two at a time between the at least one tandem etch processing chamber and the loadlock chamber.

30. The system of claim 28, further comprising a centrally located pumping aperture in communication with a vacuum pump, the centrally located pumping aperture being configured to simultaneously pump both the first and second adjacently positioned processing chambers to an equal pressure.

31. The system of claim 28, wherein a lower portion of the first and second adjacently positioned processing chambers includes a selectively actuated valve configured to communicate wafers therethrough into the lower portion of the first and second adjacently positioned processing chambers.

32. The system of claim 28, wherein the first and second adjacently positioned processing chambers each comprise a selectively actuated wafer support configured to move between a processing position and a loading position, wherein the loading position corresponds to a position in a lower portion of the respective processing chamber adjacent an aperture configured to communicate wafers into and out of the processing chamber, and wherein the processing position corresponds to a position in an upper portion of the respective processing chamber adjacent the respective gas distribution assembly.

33. The system of claim 32, further comprising a skirt member slidably disposed within each of the processing chambers and coupled to the selectively actuated wafer support, wherein the selectively actuated wafer support;

gas distribution assembly, and skirt member form a variable volume plasma processing region therein.

34. The system of claim 33, wherein each skirt member provides a plasma shield between the variable volume plasma processing region and a respective adjacent region in fluid communication with the first and second adjacently positioned processing chambers.

35. The system of claim 28, wherein the first and second plasma generation devices comprise at least one of an electrode, a coil, and a toroidal plasma generation conduit.