Process for preventing gas leaks in an atmospheric thermal processing chamber

• US 6,075,922 A
• Filed: 08/07/1997
• Issued: 06/13/2000
• Est. Priority Date: 08/07/1997
• Status: Expired due to Term

• Current Assignee: STEAG RTP Systems, Inc. (KSBG Kommunale Beteiligungsgesellschaft GmbH & Company KG)
• Original Assignee: STEAG RTP Systems, Inc. (KSBG Kommunale Beteiligungsgesellschaft GmbH & Company KG)
• Inventors: Wasserman, Yuval, Hu, Yao Zhi, Tay, Sing Pin
• Primary Examiner(s): Walberg, Teresa
• Assistant Examiner(s): Fuqua, Shawntina T.
• Application Number:
  US08/908,228
• Time in Patent Office: 1,041 Days
• Field of Search: 392/416, 392/418, 219/405, 219/411, 219/390, 118/724, 118/725, 118/50.1, 432/152, 438/795, 427/557, 427/559
• US Class Current: 392/416
• CPC Class Codes: F26B 21/10 Temperature; Pressure F26B23/026 takes precedence
• CPC Class Codes: H01L 21/67017 Apparatus for fluid treatment H01L21/67126, H01L21/6715 take precedence
• CPC Class Codes: H01L 21/67253 Process monitoring, e.g. flow or thickness monitoring

Abstract

A process and system for preventing gases from either leaking into or out of a thermal processing chamber that is designed to operate at or near atmospheric pressure is disclosed. For instance, in one embodiment, gases are prevented from leaking into a thermal processing chamber by maintaining the pressure within the chamber at levels that are slightly greater than atmospheric pressure. In an alternative embodiment, in order to prevent gases from leaking out of the chamber, the pressure within the chamber is maintained at levels slightly less than atmospheric pressure. During operation of the thermal processing chamber, a gas is continuously circulated through the chamber. In order to carry out the process of the present invention, a pressure control device can be placed upon the gas outlet for maintaining the pressure within the chamber within a desired range.

Claims

1. A process for preventing atmospheric gases from leaking into a thermal processing chamber, said process comprising the steps of:

providing a thermal processing chamber for heat treating semiconductor wafers, said thermal processing chamber including a gas inlet and a gas outlet;

placing a semiconductor wafer in said thermal processing chamber;

subjecting said semiconductor wafer to light energy for heating said wafer;

continuously flowing a gas through said thermal processing chamber, said gas entering said gas inlet and exiting said gas outlet; and

maintaining a pressure within said thermal processing chamber that is greater than the pressure of the atmosphere outside said thermal processing chamber for preventing atmospheric gases from leaking into said chamber, said pressure within said thermal processing chamber being from about 0.5 mm Hg to about 5 mm Hg greater than said atmospheric pressure.

2. A process as defined in claim 1, wherein said thermal processing chamber is maintained at a pressure of from about 0.5 mm Hg to about 3 mm Hg greater than said atmospheric pressure.

3. A process as defined in claim 1, wherein said thermal processing chamber is maintained at a pressure of from about 0.5 mm Hg to about 1.5 mm Hg greater than said atmospheric pressure.

4. A process as defined in claim 1, wherein said thermal processing chamber includes a pressure control device in communication with said gas outlet for controlling said pressure within said chamber.

5. A process as defined in claim 4, wherein said pressure control device is in communication with a pressure gage and a controller, said controller receiving pressure information from said pressure gage and, based on said information, adjusting said pressure control device for controlling said pressure within said thermal processing chamber.

6. A process as defined in claim 5, wherein said controller comprises a microprocessor.

7. A process as defined in claim 1, wherein said gas flowing through said thermal processing chamber is an inert gas.

8. A process as defined in claim 7, wherein said inert gas comprises nitrogen.

9. A process as defined in claim 1, wherein said gas that flows through said thermal processing chamber contains a gaseous reactant that reacts with said semiconductor wafer.

10. A process for preventing atmospheric gases from leaking into a thermal processing chamber during the processing of semiconductor wafers, said process comprising the steps of:

providing a thermal processing chamber for heat treating semiconductor wafers, said thermal processing chamber including a gas inlet and a gas outlet, said gas outlet being in communication with a pressure control device;

placing a semiconductor wafer in said thermal processing chamber;

subjecting said semiconductor wafer to light energy for heating said wafer;

continuously flowing a gas through said thermal processing chamber, said gas entering said gas inlet and exiting said gas outlet; and

controlling said pressure control device for maintaining a pressure within said thermal processing chamber that is greater than the pressure of the atmosphere outside said thermal processing chamber, said pressure within said chamber being from about 0.5 mm Hg to about 5 mm Hg greater than said atmospheric pressure.

11. A process as defined in claim 10, wherein said pressure control device is controlled such that said pressure within said thermal processing chamber is maintained in an amount from about 0.5 mm to about 3.0 mm Hg greater than said atmospheric pressure.

12. A process as defined in claim 10, herein said pressure control device is controlled such that said pressure within said thermal processing chamber is maintained in an amount from about 0.5 mm Hg to about 1.5 mm Hg greater than said atmospheric pressure.

13. A process as defined in claim 10, wherein said thermal processing chamber further includes a pressure indicating apparatus in communication with a controller, said controller being configured to automatically control said pressure control device based on information received from said pressure indicating apparatus.

14. A process as defined in claim 13, wherein said pressure control device comprises a throttle valve.

15. A process as defined in claim 13, wherein said controller comprises a microprocessor.

16. A process as defined in claim 10, wherein said gas flowing through said thermal processing chamber is an inert gas.

17. A process as defined in claim 10, wherein said gas flowing through said thermal processing chamber contains a gaseous reactant, said gaseous reactant reacting with said semiconductor wafer.

18. A process for preventing gases from escaping from a thermal processing chamber, said process comprising the steps of:

providing a thermal processing chamber for heat treating and semiconductor wafers, said thermal processing chamber including a gas inlet and a gas outlet;

placing a semiconductor wafer in said thermal processing chamber;

subjecting said semiconductor wafer to light energy for heating said wafer;

continuously flowing a gas through said thermal processing chamber, said gas entering said gas inlet and exiting said gas outlet; and

maintaining a pressure within said thermal processing chamber that is less than the pressure of the atmosphere outside said chamber for preventing said gas flowing through said chamber from leaking out of said chamber, said pressure within said thermal processing chamber being maintained in an amount of from about 0.5 mm Hg to about 5 mm Hg less than said atmospheric pressure.

19. A process as defined in claim 18, wherein said pressure within said thermal processing chamber is maintained within a range of from about 0.5 mm Hg to about 3.0 mm Hg less than said atmospheric pressure.

20. A process as defined in claim 18, wherein said gas flowing through said thermal processing chamber contains a gaseous reactant that reacts with said semiconductor wafer.

21. A process as defined in claim 18, wherein said thermal processing chamber further comprises a pressure control device in communication with said gas outlet, and wherein said pressure in said thermal processing chamber is maintained below said atmospheric pressure by adjusting said pressure control device.

22. A process for preventing gases from escaping from a thermal processing chamber, said process comprising the steps of:

providing a thermal processing chamber for heat treating semiconductor wafers, said thermal processing chamber including a gas inlet and a gas outlet, said gas outlet being in communication with a pressure control device;

placing a semiconductor wafer in said thermal processing chamber;

subjecting said semiconductor wafer to light energy for heating said wafer;

continuously flowing a gas through said thermal processing chamber, said gas entering said gas inlet and exiting said gas outlet;

controlling said pressure control device for maintaining a pressure within said thermal processing chamber that is less than the pressure of the atmosphere outside said thermal processing chamber, said pressure within said chamber being from about 0.5 mm Hg to about 5 mm Hg less than said atmospheric pressure.

23. A process as defined in claim 22, wherein said pressure control device is controlled such that said pressure within said thermal processing chamber is maintained in an amount from about 0.5 mm Hg to about 3.0 mm Hg less than said atmospheric pressure.

24. A process as defined in claim 22, wherein said pressure control device is controlled such that said pressure within said thermal processing chamber is maintained in an amount from about 0.5 mm Hg to about 1.5 mm Hg less than said atmospheric pressure.

25. A process as defined in claim 22, wherein said thermal processing chamber further includes a pressure indicating apparatus in communication with a controller, said controller being configured to automatically control said pressure control device based on information received from said pressure indicating apparatus.

26. A process as defined in claim 25, wherein said controller comprises a microprocessor.