MULTI-GAS STRAIGHT CHANNEL SHOWERHEAD

• US 20090098276A1
• Filed: 10/16/2007
• Published: 04/16/2009
• Est. Priority Date: 10/16/2007
• Status: Active Grant

• Current Assignee: Applied Materials Incorporated
• Original Assignee: Applied Materials Incorporated
• Inventors: BURROWS, Brian H., Nijhawan, Sandeep, Grayson, Jacob, Stevens, Ronald, Washington, Lori D., Felsch, James D., Choi, Kenric T., Tam, Alexander, Myo, Nyi O., Acharya, Sumedh
• Granted Patent: US 7,976,631 B2
• Time in Patent Office: Days
• US Class Current: 427/8
• CPC Class Codes: C23C 16/45514 Mixing in close vicinity to the substrate
• CPC Class Codes: C23C 16/45519 Inert gas curtains
• CPC Class Codes: C23C 16/45565 Shower nozzles
• CPC Class Codes: C23C 16/45574 Nozzles for more than one gas
• CPC Class Codes: C23C 16/45578 Elongated nozzles, tubes with holes
• CPC Class Codes: C30B 25/14 Feed and outlet means for the gases; Modifying the flow of the reactive gases
• CPC Class Codes: C30B 29/403 AIII-nitrides
• CPC Class Codes: Y10T 137/0318 Processes
• CPC Class Codes: Y10T 137/87153 Plural noncommunicating flow paths

Abstract

A method and apparatus that may be utilized for chemical vapor deposition and/or hydride vapor phase epitaxial (HVPE) deposition are provided. In one embodiment, a metal organic chemical vapor deposition (MOCVD) process is used to deposit a Group III-nitride film on a plurality of substrates. A Group III precursor, such as trimethyl gallium, trimethyl aluminum or trimethyl indium and a nitrogen-containing precursor, such as ammonia, are delivered to a plurality of straight channels which isolate the precursor gases. The precursor gases are injected into mixing channels where the gases are mixed before entering a processing volume containing the substrates. Heat exchanging channels are provided for temperature control of the mixing channels to prevent undesirable condensation and reaction of the precursors.

Claims

1. A showerhead apparatus comprising:

a plurality of straight and parallel gas flow channels for a first precursor gas; and

a plurality of straight and parallel gas flow channels for a second precursor gas,

wherein the gas flow channels for the first precursor gas are parallel to the gas flow channels for the second precursor gas.

2. The apparatus of claim 1, further comprising a plurality of straight and parallel gas flow channels for an inert gas, wherein the gas flow channels for the inert gas are parallel to the gas flow channels for the first precursor gas and the gas flow channels for the second precursor gas.

3. The apparatus of claim 2, wherein each of the gas flow channels for the inert gas is disposed between one of the gas flow channels for the first precursor gas and one of the gas flow channels for the second precursor gas.

4. The apparatus of claim 1, further comprising:

a plurality of first gas injection holes in fluid communication with the gas flow channels for the first precursor gas;

a plurality of second gas injection holes in fluid communication with the gas flow channels for the second precursor gas; and

mixing channels disposed downstream from said first and said second gas injection holes for mixing the first precursor gas injected through said first gas injection holes and the second precursor gas injected through said second gas injection holes.

5. The apparatus of claim 4, further comprising a plurality of straight and parallel heat exchanging channels extending across the surface of the showerhead, wherein the mixing channels and the heat exchanging channels are parallel and are alternately arranged across the surface of the showerhead.

6. A showerhead apparatus comprising:

a first gas flow channel;

a second gas flow channel;

a plurality of first gas injection holes in fluid communication with said first gas flow channel;

a plurality of second gas injection holes in fluid communication with said second gas flow channel;

mixing channels disposed downstream from said first and said second gas injection holes for mixing a first gas injected through said first gas injection holes and a second gas injected through said second gas injection holes.

7. The apparatus of claim 6, wherein the mixing channels are formed in a surface of the showerhead apparatus which faces a substrate processing volume.

8. The apparatus of claim 6, wherein the mixing channels comprise straight and parallel channels extending across a surface of the showerhead.

9. The apparatus of claim 8, further comprising a plurality of straight and parallel heat exchanging channels extending across the surface of the showerhead, wherein the mixing channels and the heat exchanging channels are parallel and are alternately arranged across the surface of the showerhead.

10. The apparatus of claim 9, wherein the heat exchanging channels are formed within walls that extend in the direction of the gas injection past the first and second gas injection holes toward a substrate processing volume.

11. The apparatus of claim 6, further comprising one or more temperature sensors for measuring the temperature of the showerhead, wherein the flow rate and temperature of heat exchanging fluid that flows through the heat exchanging channels is controlled based on the measured temperature.

12. A showerhead apparatus comprising:

first gas flow channels;

second gas flow channels;

gas injection holes in fluid communication with each of the first and second gas flow channels; and

heat exchanging channels disposed between the gas injection holes, and formed within walls that extend in the direction of the gas injection past the gas injection holes toward a substrate processing volume, wherein the exterior of the walls define mixing channels into which first gas and second gas are injected through the gas injection holes to be mixed therein.

13. The apparatus of claim 12, wherein the mixing channels are defined through a surface of the showerhead apparatus which faces a substrate processing volume.

14. The apparatus of claim 12, wherein the heat exchanging channels have substantially parallel exterior walls extending in the direction of the gas injection.

15. The apparatus of claim 12, wherein the mixing channels and heat exchanging channels are straight channels extending across a surface of the showerhead.

16. The apparatus of claim 12, wherein the gas injection holes near the perimeter of the showerhead apparatus are larger than the gas injection holes near the center of the showerhead apparatus.

17. The apparatus of claim 12, wherein the density of the gas injection holes near the perimeter of the showerhead apparatus are greater than the density of the gas injection holes near the center of the showerhead apparatus.

18. A showerhead apparatus comprising:

first gas flow channels;

second gas flow channels; and

gas injection holes in fluid communication with each of the first and second gas flow channels,

wherein the gas injection holes are arranged to define a plurality of substantially wedge shaped gas injection zones, each gas injection zone having gas injection holes for injecting a gas that is different from an adjacent gas injection zone.

19. The apparatus of claim 18, further comprising third gas flow channels, wherein the gas injection zones include first gas injection zones, second gas injection zones, and third gas injection zones, and wherein each of the third gas injection zones is between one of the first gas injection zones and one of the second gas injection zones.

20. The apparatus of claim 19, wherein the first gas comprises a first metal precursor and the second gas comprises a nitrogen precursor, and wherein the third gas comprises an inert gas.

21. A method for chemical vapor deposition using a showerhead having a mixing zone, comprising:

flowing first and second gases into channels formed in the showerhead; and

injecting said first and second gases that are flowing in the channels into the mixing zone.

22. The method of claim 21, wherein the first gas is flowed through a first channel and the second gas is flowed through a second channel.

23. The method of claim 21, further comprising flowing a heat exchanging fluid through a heat exchanging channel formed in the showerhead.

24. The method of claim 21, further comprising flowing a third gas into channels formed in the showerhead, wherein the first and second gases comprise precursor gases and the third gas comprises an inert gas.

25. The method of claim 21, wherein the first and second gases comprise precursor gases and the first precursor gas comprises a Group III precursor and the second precursor gas comprises a Group V precursor.

26. The method of claim 25, wherein the precursor gases comprise MOCVD precursors.

27. The method of claim 25, wherein the precursor gases comprise HVPE precursors.

28. The method of claim 25, wherein the precursor gases have the general formula MX₃ and M includes one of gallium, aluminum or indium and X includes one of chlorine, bromine, or iodine.

29. The method of claim 25, wherein the first and second precursor gases comprise plasma species.

30. The method of claim 21, wherein the first gas is flowed through a plurality of first gas channels that are straight and parallel and the second gas is flowed through a plurality of second gas channels that are straight and parallel, and wherein the first gas channels and the second channels are parallel.

31. The method of claim 21, further comprising:

measuring the showerhead temperature, and;

controlling the showerhead temperature by adjusting a heat exchanging fluid temperature and flow rate.