High throughput OMVPE apparatus

• US 6,217,937 B1
• Filed: 07/15/1998
• Issued: 04/17/2001
• Est. Priority Date: 07/15/1998
• Status: Expired due to Term

• Current Assignee: Cornell Research Foundation Incorporated (Cornell University)
• Original Assignee: Cornell Research Foundation Incorporated (Cornell University)
• Inventors: Shealy, J. Richard
• Primary Examiner(s): BUEKER, RICHARD R
• Application Number:
  US09/115,520
• Time in Patent Office: 1,007 Days
• Field of Search: 118/708, 118/712, 118/715, 118/725, 118/730, 427/255.25, 427/255.5
• US Class Current: 427/255.25
• CPC Class Codes: C23C 16/44 characterised by the method of coating C23C16/04 takes precedence
• CPC Class Codes: C23C 16/4405 Cleaning of reactor or parts inside the reactor by using reactive gases
• CPC Class Codes: C23C 16/4412 Details relating to the exhausts, e.g. pumps, filters, scrubbers, particle traps
• 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
• CPC Class Codes: C23C 16/45561 Gas plumbing upstream of the reaction chamber
• CPC Class Codes: C30B 25/08 Reaction chambers; Selection of materials therefor
• CPC Class Codes: C30B 25/14 Feed and outlet means for the gases; Modifying the flow of the reactive gases

Abstract

A cold wall reactor having inner and outer walls defining an annular reactor cell. A susceptor is rotatably mounted in the cell, and received wafers to be treated by gases flowing axially through the cell. The outer wall of the reactor is normally cooled, but is heated by a suitable furnace to provide a hot wall reactor when cleaning of the cell is required.

Claims

1. A cold wall reactor, comprising:

an inner wall surrounding a central cavity which has a closed end and an open end;

an outer wall spaced from and surrounding said inner wall to provide a reactor cell therebetween;

a susceptor rotatably mounted in said cell; and

a heater within said central cavity for heating said susceptor.

2. The reactor of claim 1, further including a furnace removably engaging said outer wall to convert said reactor to a hot wall reactor.

3. The reactor of claim 1, further including cooling means for said outer wall for operating said reactor as a cold wall reactor, and heating means for said outer wall for converting said reactor to a hot wall reactor.

4. The reactor of claim 1, wherein said heater is an RF coil for inductively heating said susceptor.

5. The reactor of claim 4, further including cooling means for said outer wall for operating said reactor as a cold wall reactor, and means for converting said reactor to hot wall operation.

6. The reactor of claim 5, wherein said inner wall and said outer wall are cylindrical.

7. The reactor of claim 5, further including a rotation fixture for supporting said susceptor for rotation in said cell.

8. The reactor of claim 7, further including a lift member for removing said susceptor from said cell.

9. The reactor of claim 7, further including a drive motor for said rotation fixture.

10. The reactor of claim 9, wherein said inner wall, said outer wall, said rotation fixture, and said lift member are cylindrical quartz tubes.

11. The reactor of claim 1, further including injectors at a first end of said reactor cell for introducing reactive gases into said cell, and exit ports at said second end of said reactor cell for removing said gases from said cell.

12. The reactor of claim 11, wherein said exit ports are aligned with corresponding injectors to produce axial flow of said gases in said cell.

13. The reactor of claim 12, wherein said susceptor is mounted on a rotation fixture which positions said susceptor in said cell and rotates said susceptor to pass through said axial flow of said gases.

14. The reactor of claim 13, wherein said inner and outer walls are generally cylindrical and are coaxial to form an annular reactor cell, and further including first and second end caps enclosing and sealing said first and second ends of said reactor cell.

15. The reactor of claim 14 wherein said annular reactor cell has a vertical axis, whereby said axial flow of said gases is vertical.

16. The reactor of claim 14, wherein said susceptor and said rotation fixture are each generally cylindrical, and surround and are coaxial with said inner wall.

17. The reactor of claim 16, further including a cooler within said cell and lying in said flow of gases between said susceptor and said exits ports.

18. The reactor of claim 17, further including a lift member for removing said susceptor from said reactor cell.

19. The reactor of claim 18, wherein said lift member is supported by said first end cap for removal of said susceptor upon removal of said first end cap.

20. The reactor of claim 19, wherein said lift member is rotatable with respect to said first end cap to accommodate wafer loading.

21. The reactor of claim 11, further including a gas distribution manifold connected to selected injectors through corresponding mass flow controllers.

22. The reactor of claim 21, further including individual reactive gas sources connectable through selected injectors to provide vertical gas zones within said reactor cell, said susceptor being rotatable through said gas zones.

23. The reactor of claim 22, further including an exit manifold, and a corresponding flow controller connecting each exit port to said manifold to control exit gas flow.

24. A gas distribution system for a reactor cell comprising:

a plurality of gas injectors connected at spaced locations to the reactor cell;

a gas distribution manifold;

a corresponding gas flow controller connected between each of said injectors and said manifold for regulating the flow of gas to the corresponding injectors;

a source of carrier gas;

a carrier gas flow controller connecting said source of carrier gas to said manifold;

at least one source of a reactant gas;

a reactant flow controller connecting said source of reactant gas to said manifold; and

a sensor connected between said distribution manifold and said carrier gas flow for regulating said controller in response to a sensed parameter in the manifold.

25. A method of controlling gas flow in a reactor, comprising:

locating material to be treated on an outwardly sloping susceptor movably mounted in an annular elongated reactor cell having inner and outer walls and having an inlet end and an outlet end;

supplying reactant gases to said reactor cell at multiple spaced inlet locations around the annular cell at said inlet end;

drawing said gases out of said reactor cell outlet end at multiple spaced exit locations around the annular cell at said outlet end to cause laminar flow of said gases across said material to be treated;

aligning said multiple spaced exit locations with corresponding multiple spaced inlet locations to produce controlled, axial, nonturbulent gas flow zones around said cell;

controlling the supply of reactant gases to provide equalized laminar flow in said zones;

locating a heat source within said inner wall;

heating said susceptor and said material to be treated; and

moving said material to be treated sequentially through said gas flow zones.

26. The method of claim 25, further including supplying said reactant gases to multiple spaced inlet locations at a top end of a reactor cell having a vertical axis, and drawing said gases out of multiple spaced outlet locations at the bottom of said reactor cell, to produce vertical laminar gas flow in said reactor cell;

and

cooling said gases prior to drawing the gases out of said cell.

27. The method of claim 26, wherein supplying reactant gases includes supplying selective quantities of gases from plural sources of carrier and reactant gases, and independently controlling the flow of said carrier and reactant gases.

28. A high throughput organometallic vapor phase epitaxy apparatus for vapor deposition of material on substrates, comprising:

an inner wall surrounding an elongated central cavity which has a closed end and an open end;

an outer wall spaced from and surrounding said inner wall to provide a reactor cell therebetween;

a susceptor movably mounted in said cell and adapted to receive a substrate; and

a heater within said central cavity for heating said susceptor and said substrate.

29. The reactor of claim 28, further including top and bottom closures to provide a closed reactor cell.

30. The reactor of claim 29, further including an inlet for supplying gas to said reactor cell and an outlet for withdrawing gas from said reactor cell, said inlet and said outlet being axially spaced to produce axial laminar gas flow within the reactor cell.

31. The reactor of claim 30, wherein said susceptor is located adjacent said inner wall and within said laminar flow and is sloped to reduce gas flow turbulence.

32. The reactor of claim 31, wherein said reactor cell is annular, and wherein said susceptor is mounted for rotation around said inner wall.

33. The reactor of claim 32, wherein said inlet includes multiple injectors spaced around said annular cell to introduce gases into said cell, and wherein said outlet includes multiple outlet ports spaced around said annular cell to remove gases from said cell.

34. The reactor of claim 33, further including a controllable gas source for supplying a selected reactive gas to said multiple injectors in said annular reactor cell.

35. The reactor of claim 34, wherein said inlet injectors and said outlet ports are aligned to provide gas flow zones in said annular cell, said susceptor being rotatable to pass said substrate through said zones successively.