Semiconductor-processing device provided with a remote plasma source for self-cleaning

• US 20020011210A1
• Filed: 01/18/2001
• Published: 01/31/2002
• Est. Priority Date: 01/18/2000
• Status: Active Grant

• Current Assignee: ASM Japan K.K. (ASM International NV)
• Original Assignee: ASM Japan K.K. (ASM International NV)
• Inventors: Sato, Kazuo, Fukuda, Hideaki, Satoh, Kiyoshi
• Granted Patent: US 6,736,147 B2
• Time in Patent Office: Days
• US Class Current: 118/715
• CPC Class Codes: C23C 16/4405 Cleaning of reactor or parts inside the reactor by using reactive gases
• CPC Class Codes: C23C 16/452 by activating reactive gas streams before their introduction into the reaction chamber, e.g. by ionisation or addition of reactive species
• CPC Class Codes: H01J 37/32357 Generation remote from the workpiece, e.g. down-stream
• CPC Class Codes: H01J 37/32862 In situ cleaning of vessels and/or internal parts

Abstract

A plasma CVD device includes a reaction chamber, a remote plasma discharge chamber that is provided remotely from the reaction chamber, and piping that links the reaction chamber and the remote plasma discharge chamber. The remote plasma discharge chamber activates cleaning gas by plasma discharge energy, and the activated cleaning gas is introduced into the inside of the reaction chamber through the piping and changes solid substances that adhere to the inside of the reaction chamber in consequence of film formation, to gaseous substances, thereby cleaning the inside of the reaction chamber. The device is characterized by at least one of the following: (a) the remote plasma discharge chamber generates active species using radio frequency oscillating output energy of a preselected frequency; (b) the piping is made of materials that are not corroded by the active species; or (c) the piping is provided with a through-flow type valve.

Claims

1. A chemical vapor deposition (CVD) device, comprising a deposition reaction chamber, a plasma discharge chamber that is provided remotely from the reaction chamber, remote plasma piping that links the reaction chamber and the remote plasma discharge chamber, wherein energy coupled to the remote plasma discharge chamber activates cleaning gas within the plasma discharge chamber, and the activated cleaning gas is brought into the inside of the reaction chamber through the piping and changes solid substances adhered to the inside of the reaction chamber as a consequence of film formation, to gaseous substances, thereby cleaning the inside of the reaction chamber, wherein internal surfaces of the piping comprises a metal not corroded by the activated cleaning gas species.

2. The CVD device according to claim 1, wherein the activated cleaning gas comprises fluorine active species.

3. The CVD device of claim 2, wherein the internal surface of the piping comprises a fluorine-passivated metal.

4. The CVD device of claim 3, wherein of the piping is made of a metal selected from the group consisting of fluorine-passivated stainless steel, aluminum, and aluminum alloy.

5. The CVD device of claim 1, wherein the piping comprises a through-flow type valve positioned between the remote plasma discharge chamber and the reaction chamber.

6. The CVD device of claim 5, wherein the activated cleaning gas comprises fluorine active species and an inner surface of the valve is made of fluorine-passivated aluminum.

7. The CVD device of claim 5, wherein the valve has an opening that, when fully open, defines a pressure drop across the valve of less than about 0.25 Torr.

8. The CVD device of claim 7, wherein the pressure drop across the valve when fully open is less than about 0.1 Torr.

9. The CVD device of claim 7, wherein the opening of the valve is sized, when fully opened, substantially equal in width to an inner surface of the piping, and the valve does not have projections, when fully opened, with respect to the inner surface of the piping.

10. The CVD device of claim 5, wherein the piping and the valve are heated to a temperature effective to prevent deposition of the cleaning gas.

11. The CVD of claim 1, further comprising a support provided within the reaction chamber, configured to support an object to be processed, and a gas-emitting plate provided at a position facing the support within the reaction chamber in order to supply reaction gas to the object to be processed to form a film on the object to be processed, wherein the activated cleaning gas is supplied through piping into the reaction chamber from holes provided on the gas-emitting plate.

12. The CVD device of claim 11, wherein the gas-emitting plate is connected to a source of power to form an in situ plasma electrode for plasma CVD within the reaction chamber.

13. The CVD device of claim 11, further comprising a gas conduit communicating with a source of reaction gas, wherein one end of the gas conduit is linked to the piping at a predetermined position between the valve and the gas-emitting plate.

14. The CVD device of claim 1, wherein the piping is straight between the remote plasma discharge chamber and the reaction chamber.

15. The CVD device of claim 1, wherein the energy activating the cleaning gas has a frequency between about 300 kHz and 500 kHz.

16. The CVD device of claim 14, wherein the energy activating the cleaning gas has a frequency between about 1,500 W and 3,000 W.

17. The CVD device of claim 1, further comprising a reaction gas inlet and a reaction gas outlet defining a horizontal flow across a substrate surface upon which material is deposited within the reaction chamber.

18. The CVD device of claim 17, wherein the piping opens into the reaction chamber downstream of the inlet and upstream of a substrate support configured for supporting a substrate within the chamber.

19. The CVD device of claim 17, wherein the reaction chamber comprises quartz walls and radiant heating elements.

20. A plasma chemical vapor deposition (CVD) reactor, comprising a reaction chamber, a remote plasma discharge chamber connected to the reaction chamber by piping, a source of cleaning gas in fluid communication with the piping upstream of the remote plasma discharge chamber, and a power source communicating energy with a frequency between about 300 kHz and 500 kHz to activate the cleaning gas within the remote plasma discharge chamber.

21. The plasma CVD reactor of claim 20, wherein the remote plasma discharge chamber is formed of metal.

22. The plasma CVD reactor of claim 21, wherein the remote plasma discharge chamber comprises anodized aluminum.

23. The plasma CVD reactor of claim 20, wherein the cleaning gas comprises a fluorine containing gas, and the piping supplies fluorine active species to the reaction chamber.

24. The plasma CVD reactor of claim 23, wherein the piping comprises internal surfaces formed of fluorine-passivated metal resistant to corrosion by fluorine active species.

25. The plasma CVD device of claim 23, wherein the piping is heated to between about 100°

C. and 200°

C.

26. The plasma CVD reactor of claim 20, further comprising a source of CVD reaction gas in fluid communication with the remote plasma discharge chamber.

27. The plasma CVD reactor of claim 20, further comprising a through-flow type valve on the piping between the remote plasma discharge chamber and the reaction chamber, the valve being configured such that, when fully opened, it defines an opening substantially equal in width to an inner surface of the piping, and the valve does not have projections, when fully opened, with respect to the inner surface of the piping.

28. The plasma CVD reactor of claim 27, wherein a pressure drop is formed across the valve when fully opened and plasma is ignited within the remote plasma discharge chamber, the pressure drop being less than 1% of a pressure at an inlet to the chamber.

29. The plasma CVD reactor of claim 20, wherein the cleaning gas comprises a fluorine-containing gas and the power source communicates energy with a power between about 1,000 W and 5,000 W to produce fluorine active species within the remote plasma discharge chamber.

30. The plasma CVD reactor of claim 29, wherein the power source communicates energy with a power between about 2,000 W and 3,000 W to produce fluorine active species within the remote plasma discharge chamber.

31. The plasma CVD reactor of claim 20, configured to maintain pressure within the reaction chamber between about 1 Torr and 8 Torr.

32. The plasma CVD reactor of claim 20, capable of removing silicon nitride deposits from surfaces of the reaction chamber at a rate of greater than or equal to about 2.0 microns/minute when the power source communicates energy with a power of less than about 3,000 W.

33. A method of cleaning a chemical vapor deposition (CVD) reaction chamber with cleaning gas provided through a remote plasma discharge chamber, comprising:

dissociating cleaning gas within the remote plasma discharge chamber by applying energy with a power of less than about 3,000 W;

supplying activated species from the remote plasma discharge chamber to the reaction chamber through a piping;

removing adhered deposits from CVD reactions on a wall of the reaction chamber at a rate of greater than or equal to about 2.0 microns/minute.

34. The method of claim 33, wherein the deposits on the reaction chamber wall comprise silicon nitride.

35. The method of claim 33, wherein the cleaning gas comprises fluorine-containing gas and the activated species comprises fluorine active species.

36. The method of claim 33, wherein the applied energy has a frequency between about 300 kHz and 500 kHz.

37. The method of claim 33, wherein supplying activated species comprises flowing NF₃ through the remote plasma discharge chamber at a rate between about 0.5 slm and 1.5 slm.

38. The method of claim 33, further comprising opening a valve on the piping after conducting a CVD reaction and prior to supplying activated species.

39. The method of claim 38, wherein opening a valve comprises withdrawing a sealing element completely from a path to form an opening substantially as wide as internal surfaces of the piping.

40. The method of claim 38, further comprising closing the valve after removing the adhered deposits.

41. A self-cleaning chemical vapor deposition (CVD) reactor, comprising a reaction chamber, a remote plasma discharge chamber connected to the reaction chamber by piping, a gaseous source of fluorine in fluid communication with the piping upstream of the remote plasma discharge chamber, the piping comprises a through-flow type valve positioned between the remote plasma discharge chamber and the reaction chamber, and a power source communicating energy with a frequency between about 300 kHz and 500 kHz to activate fluorine within the remote plasma discharge chamber.

42. The CVD reactor of claim 41, wherein wherein a pressure drop is formed across the valve when fully opened and plasma is ignited within the remote plasma discharge chamber, the pressure drop being less than about 5% of a pressure at an inlet to the chamber.

43. The CVD reactor of claim 42, wherein the pressure drop is less than about 1% of the pressure at the inlet.

44. The CVD reactor of claim 42, wherein an internal surface of the piping comprises a fluorine-passivated metal.