Buffer chamber for integrating physical and chemical vapor deposition chambers together in a processing system

• US 6,183,564 B1
• Filed: 11/12/1998
• Issued: 02/06/2001
• Est. Priority Date: 11/12/1998
• Status: Expired due to Term

• Current Assignee: Tokyo Electron Limited
• Original Assignee: Tokyo Electron Limited
• Inventors: Reynolds, Glyn J., Hillman, Joseph T.
• Primary Examiner(s): Lund, Jeffrie R.
• Assistant Examiner(s): MACARTHUR, SYLVIA
• Application Number:
  US09/190,870
• Time in Patent Office: 817 Days
• Field of Search: 118/719, 118/715, 156/345, 204/298.23, 204/298.25, 204/298.31, 204/298.35
• US Class Current: 118/719
• CPC Class Codes: H01L 21/6719 characterized by the construction of the processing chambers, e.g. modular processing chambers
• CPC Class Codes: H01L 21/67196 characterized by the construction of the transfer chamber
• CPC Class Codes: H01L 21/67207 comprising a chamber adapted to a particular process

Abstract

An apparatus for processing a substrate in a processing system having multiple process chambers and a common transfer chamber comprises a process chamber having a process space to receive and process a substrate and a buffer chamber defining a buffer space. The buffer chamber is positioned beneath the process chamber and is configured for interfacing with a transfer chamber of a processing system for receiving a substrate to be processed. A passage is formed between the process and buffer chambers for moving a substrate between the process space and buffer space and a movable substrate stage in the buffer space is operable for moving vertically in said passage between a first position wherein the substrate is positioned in the buffer space and a second position wherein the substrate is positioned within the process space of the process chamber. A sealing mechanism is operable for sealing said passage to isolate the process chamber and a pumping system is coupled to the buffer chamber for purging the buffer space of contaminants which may leak from the process chamber to generally reduce the escape of the contaminants through the buffer chamber and into the common transfer chamber and other process chambers of a multiple chamber system.

Claims

1. An apparatus for processing a substrate in a processing system having multiple process chambers and a common transfer chamber which is used for moving substrates between the multiple process chambers of the system, the apparatus comprising:

a process chamber having a process space therein for receiving and processing a substrate;

a buffer chamber defining a buffer space therein, the buffer chamber positioned beneath the process chamber and configured for interfacing with a transfer chamber of a processing system for receiving a substrate to be processed;

a passage formed between the process and buffer chambers for moving a substrate between the process space and buffer space;

a movable substrate stage positioned in the buffer space and configured for receiving a substrate, the substrate stage operable for moving vertically in said passage between a first position wherein the substrate is positioned in the buffer space and a second position wherein the substrate is positioned within the process space of the process chamber;

the substrate stage further operable for sealing said passage when moved to the second position to isolate the process chamber from the buffer chamber and operable for unsealing the passage when moved to the first position;

a sealing mechanism engaging the passage, the sealing mechanism operable to seal the passage and isolate the process space from the buffer space when the substrate stage is in the first position, the sealing mechanism further operable to unseal the passage so the substrate stage may be moved to the second position;

a pumping system coupled to the buffer chamber for purging the buffer space of contaminants which may leak from the process chamber to generally reduce the escape of the contaminants through the buffer chamber and into the common transfer chamber and other process chambers of a multiple chamber system.

2. The apparatus of claim 1 wherein said sealing mechanism includes a gate valve.

3. The apparatus of claim 1 wherein said pump system comprises a cryogenic panel positioned adjacent a wall of the buffer chamber, the cryogenic panel operable for capturing and thereby pumping gas from the buffer chamber to reduce contaminants in the buffer chamber.

4. The apparatus of claim 3 wherein said cryogenic panel is thermally coupled to a source of refrigerant for cooling said panel to effect pumping of the gas.

5. The apparatus of claim 3 wherein said cryogenic panel is thermally coupled to an expander head, the expander head operable for rapidly expanding a coolant gas for cooling said panel to effect pumping.

6. The apparatus of claim 3 further comprising a thermal shield positioned in the buffer chamber generally between the cryogenic panel and the passage, the thermal shield operable for absorbing radiated thermal energy associated with the process chamber and effectively shielding said cryogenic panel from said radiated energy.

7. The apparatus of claim 6 wherein said thermal shield is positioned between said cryogenic panel and the substrate stage for absorbing radiated thermal energy from the substrate stage.

8. The apparatus of claim 1 further comprising a gas sensing system operably coupled to the buffer chamber for detecting undesired gases to be removed by the pumping system from the buffer chamber.

9. The apparatus of claim 8 wherein said gas sensing system includes a plasma tube operable for exciting gas species and an optical sensor to detect the excited species.

10. The apparatus of claim 8 wherein said gas sensing system includes a residual gas analyzer.

11. The apparatus of claim 1 wherein said process and buffer chambers share a common wall, the passage being formed by an opening in the common wall.

12. The apparatus of claim 11 wherein said substrate stage includes a sealing device, the sealing device operable to compress against said wall to form an airtight seal of the passage between the process chamber and the buffer chamber when the substrate stage is moved to the second position.

13. The apparatus of claim 1 wherein said substrate stage comprises a first actuating mechanism and a second actuating mechanism movable with respect to the first actuating mechanism, the first actuating mechanism operable for moving the substrate stage to the second position to seal the passage and the second actuating mechanism operable for further moving a portion of the substrate stage to position a substrate in the process space when the substrate stage is in the second position.

14. The apparatus of claim 1 further comprising an isolation valve positioned between the transfer chamber and the buffer chamber, the isolation valve operable for closing and sealing the buffer chamber to prevent migration of contaminants from the buffer chamber into the transfer chamber.

15. The apparatus of claim 1 wherein said pumping system further includes a cryogenic pump for removing contaminants and water from the process.

16. The apparatus of claim 1 wherein said pumping system further includes a cryogenic water pump for removing water.

17. A processing system for processing a substrate using multiple fabrication processes, the system comprising:

a first process chamber for processing a substrate;

a second process chamber having a process space therein for receiving and processing a substrate;

a transfer chamber operably coupled to the first and second process chambers for transferring substrates to be processed to the first and second process chambers;

a buffer chamber having a buffer space therein, the buffer chamber positioned below the second process chamber and coupled to the transfer chamber;

a passage formed between the second process chamber and the buffer chamber to provide communication between the process space and buffer space for moving a substrate between the buffer chamber and the second process chamber;

a movable substrate stage positioned in the buffer space and configured for receiving a substrate from the transfer chamber, the substrate stage operable for moving vertically in said passage between a first position wherein the substrate is positioned in the buffer space and a second position wherein the substrate is positioned within the process space of the second process chamber;

the substrate stage further operable for sealing said passage when moved to the second position to isolate the process chamber from the buffer chamber and operable for unsealing the passage when moved to the first position;

a sealing mechanism engaging the passage, the sealing mechanism operable to seal the passage and isolate the process space from the buffer space when the substrate stage is in the first position, the sealing mechanism further operable to unseal the passage so the substrate stage may be moved to the second position;

a pumping system coupled to the buffer chamber for purging the buffer space of contaminants which may leak from the second process chamber to generally reduce the escape of the contaminants through the buffer chamber and into the common transfer chamber and the first process chamber.

18. The system of claim 17 wherein said sealing mechanism includes a gate valve.

19. The system of claim 18 wherein said pumping system comprises a cryogenic panel positioned adjacent a wall of the buffer chamber, the cryogenic panel operable capturing and thereby pumping gas from the buffer chamber to reduce contaminants in the buffer chamber.

20. The system of claim 19 further comprising a thermal shield positioned in the buffer chamber generally between the cryogenic panel and the passage, the thermal shield operable for absorbing radiated thermal energy associated with the process chamber and effectively shielding said cryogenic panel from said radiated energy.

21. The system of claim 17 further comprising a gas sensing system positioned in the buffer chamber for detecting undesired gases to be removed by the pumping system from the buffer chamber to reduce contaminants in the buffer chamber.

22. The system of claim 17 wherein said substrate stage comprises a first actuating mechanism and a second actuating mechanism movable with respect to the first actuating mechanism, the first actuating mechanism operable for moving the substrate stage to the second position to seal the passage and the second actuating mechanism operable for further moving a portion of the substrate stage to position a substrate in the process space when the substrate stage is in the second position.

23. The system of claim 17 further comprising an isolation valve positioned between the transfer chamber and the buffer chamber, the isolation valve operable for closing and sealing the buffer chamber to prevent migration of contaminants from the buffer chamber into the transfer chamber.

24. The system of claim 17 wherein said first process chamber is a physical vapor deposition chamber for performing a physical vapor deposition process and said second process chamber is a chemical vapor deposition chamber for performing a chemical vapor deposition process.

25. The system of claim 17 wherein said second process chamber is a physical vapor deposition chamber for performing a physical vapor deposition process and said first process chamber is a chemical vapor deposition chamber for performing a chemical vapor deposition process.

26. A processing system for processing a substrate using multiple fabrication processes, the system comprising:

a process module including a first process chamber for processing a substrate and a second process chamber having a process space therein for receiving and processing a substrate;

a buffer chamber having a buffer space therein, the buffer chamber positioned below the second process chamber, a passage formed between the second process chamber and the buffer chamber to provide communication therebetween for moving a substrate between the buffer chamber and the second process chamber;

a transfer chamber operably coupled to the buffer chamber for transferring substrates to be processed to the buffer chamber;

a movable substrate stage positioned in the buffer space and configured for receiving a substrate from the transfer chamber, the substrate stage operable for moving vertically in said passage between a first position wherein the substrate is positioned in the buffer space and a second position wherein the substrate is positioned within the process space of the second process chamber;

the substrate stage further operable for sealing said passage when moved to the second position to isolate the process chamber from the buffer chamber and operable for unsealing the passage when moved to the first position;

a sealing mechanism engaging the passage, the sealing mechanism operable to seal the passage and isolate the process space from the buffer space when the substrate stage is in the first position, the sealing mechanism further operable to unseal the passage so the substrate stage may be moved to the second position;

a pumping system coupled to the buffer chamber for purging the buffer space of contaminants which may leak from the first and second process chambers to generally reduce the escape of the contaminants from the process module and into the transfer chamber.

27. The system of claim 26 wherein said buffer chamber is also positioned below the first process chamber with a passage formed between the first process chamber and the buffer chamber to provide communication therebetween for moving a substrate between the buffer chamber and the first process chamber;

and further comprising an indexing mechanism operably communicating with the first and second process chambers for moving a substrate between the first and second process chambers.

28. The system of claim 26 wherein said pumping system comprises a cryogenic panel positioned adjacent a wall of the buffer chamber, the cryogenic panel operable capturing and thereby pumping gas from the buffer chamber to reduce contaminants in the buffer chamber.

29. The system of claim 28 further comprising a thermal shield positioned in the buffer chamber generally between the cryogenic panel and the passage, the thermal shield operable for absorbing radiated thermal energy associated with the process chamber and effectively shielding said cryogenic panel from said radiated energy.

30. The system of claim 26 further comprising a gas sensing system positioned in the buffer chamber for detecting undesired gases to be removed by the pumping system from the buffer chamber to reduce contaminants in the buffer chamber.

31. The system of claim 26 wherein said substrate stage comprises a first actuating mechanism and a second actuating mechanism movable with respect to the first actuating mechanism, the first actuating mechanism operable for moving the substrate stage to the second position to seal the passage and the second actuating mechanism operable for further moving a portion of the substrate stage to position a substrate in the process space when the substrate stage is in the second position.

32. The system of claim 26 further comprising an isolation valve positioned between the transfer chamber and the buffer chamber, the isolation valve operable for closing and sealing the buffer chamber to prevent migration of contaminants from the buffer chamber into the transfer chamber.

33. The system of claim 26 wherein said first and second process chambers of the module are a physical vapor deposition chambers for performing physical vapor deposition processes.

34. The system of claim 26 wherein said first and second process chambers of the module are chemical vapor deposition chambers for performing chemical vapor deposition processes.

35. The system of claim 26 wherein one of said first and second process chambers of the module is an etch chamber.

36. The system of claim 26 wherein one of said first and second process chambers of the module is degas chamber.

37. The system of claim 26 wherein one of said first and second process chambers of the module is a preheat chamber.

38. An apparatus for processing a substrate in a processing system having multiple process chambers and a common transfer chamber which is used for moving substrates between the multiple process chambers of the system, the apparatus comprising:

a process chamber having a process space therein for receiving and processing a substrate;

a buffer chamber defining a buffer space therein, the buffer chamber positioned beneath the process chamber and configured for interfacing with a transfer chamber of a processing system for receiving a substrate to be processed;

a passage formed between the process and buffer chambers for moving a substrate between the process space and buffer space;

a movable substrate stage positioned in the buffer space and configured for receiving a substrate, the substrate stage operable for moving vertically in said passage between a first position wherein the substrate is positioned in the buffer space and a second position wherein the substrate is positioned within the process space of the process chamber;

the substrate stage further operable for sealing said passage when moved to the second position to isolate the process chamber from the buffer chamber and operable for unsealing the passage when moved to the first position;

a sealing mechanism engaging the passage, the sealing mechanism operable to seal the passage and isolate the process space from the buffer space when the substrate stage is in the first position;

the sealing mechanism further operable to unseal the passage so the substrate stage may be moved to the second position;

a pumping system coupled to the buffer chamber for purging the buffer space of contaminants which may leak from the process chamber to generally reduce the escape of the contaminants through the buffer chamber and into the common transfer chamber and other process chambers of a multiple chamber system;

a gas sensing system operably coupled to the buffer chamber for detecting undesired gases to be removed by the pumping system from the buffer chamber, the gas sensing system.

39. The apparatus of claim 38 wherein the substrate stage is further operable for sealing said passage when moved to the second position to isolate the process chamber from the buffer chamber and is operable for unsealing the passage when moved to the first position.

40. The apparatus of claim 38 further comprising a transfer chamber operably coupled to the buffer chamber for transferring substrates to be processed to the buffer chamber, an isolation valve positioned between the transfer chamber and the buffer chamber, the isolation valve operable for closing and sealing the buffer chamber to generally prevent migration of contaminants from the buffer chamber into the transfer chamber.

41. The apparatus of claim 38 wherein said gas sensing system is operably coupled to the isolation valve to maintain the isolation valve closed for period of time while the buffer space is purged to generally prevent migration of the contaminants into the transfer chamber.

42. The apparatus of claim 38 wherein said pump system comprises a cryogenic panel positioned adjacent a wall of the buffer chamber, the cryogenic panel operable for capturing and thereby pumping gas from the buffer chamber to reduce contaminants in the buffer chamber.

43. The apparatus of claim 38 wherein said gas sensing system includes a plasma tube operable for exciting gas species and an optical sensor to detect the excited species.

44. The apparatus of claim 38 wherein said pumping system further includes a cryogenic pump for removing contaminants and water from the process.

45. The apparatus of claim 38 wherein said pumping system further includes a cryogenic water pump for removing water.