Barrier formation using novel sputter-deposition method

• US 20030022487A1
• Filed: 01/09/2002
• Published: 01/30/2003
• Est. Priority Date: 07/25/2001
• Status: Active Grant

• Current Assignee: Applied Materials Incorporated
• Original Assignee: Applied Materials Incorporated
• Inventors: Cha, Yonghwa Chris, Yu, Sang Ho, Wee, Ho Sun, Ahmad, Hafiz Farooq, Yoon, Ki Hwan
• Granted Patent: US 6,740,585 B2
• Time in Patent Office: Days
• US Class Current: 438/642
• CPC Class Codes: C23C 14/566 using a load-lock chamber
• CPC Class Codes: C23C 16/06 characterised by the deposition of metallic material
• CPC Class Codes: C23C 16/54 Apparatus specially adapted for continuous coating
• CPC Class Codes: H01L 21/28518 the conductive layers comprising silicides H01L21/28537 takes precedence
• CPC Class Codes: H01L 21/2855 by physical means, e.g. sputtering, evaporation H01L21/28518 - H01L21/28537 and H01L21/28568 take precedence
• CPC Class Codes: H01L 21/28556 by chemical means, e.g. CVD, LPCVD, PECVD, laser CVD H01L21/28518 - H01L21/28537 and H01L21/28568 take precedence
• CPC Class Codes: H01L 21/76843 formed in openings in a dielectric
• CPC Class Codes: H01L 21/76846 Layer combinations
• CPC Class Codes: H01L 21/76855 After-treatment introducing at least one additional element into the layer
• CPC Class Codes: H01L 21/76864 Thermal treatment
• CPC Class Codes: H01L 21/76876 for deposition from the gas phase, e.g. CVD

Abstract

Methods and apparatus are provided for forming a metal or metal silicide barrier layer. In one aspect, a method is provided for processing a substrate including positioning a substrate having a silicon material disposed thereon in a substrate processing system, depositing a first metal layer on the substrate surface in a first processing chamber, forming a metal silicide layer by reacting the silicon material and the first metal layer, and depositing a second metal layer in situ on the substrate in a second processing chamber. In another aspect, the method is performed in an apparatus including a load lock chamber, the intermediate substrate transfer region including a first substrate transfer chamber and a second substrate transfer chamber, a physical vapor deposition processing chamber coupled to the first substrate transfer chamber, and a chemical vapor deposition chamber coupled to the second substrate transfer chamber.

Claims

1. A system for processing a substrate, comprising:

a load lock chamber;

an intermediate substrate transfer region comprising a first substrate transfer chamber and a second substrate transfer chamber, wherein the first substrate transfer chamber is operated at a first pressure and the second transfer chamber is operated at a second pressure less than the first pressure and the first transfer chamber is coupled to the load lock chamber and the second substrate transfer chamber is coupled to the first substrate transfer chamber;

at least one physical vapor deposition (PVD) processing chamber coupled to the first substrate transfer chamber;

at least one chemical vapor deposition (CVD) processing chamber coupled to the second substrate transfer chamber; and

at least one annealing chamber coupled to the second substrate transfer chamber.

2. The system of claim 1, wherein the intermediate substrate transfer region comprises a plurality of vacuum pumps communicating with the intermediate substrate transfer region and each of the processing chambers, wherein the plurality of pumps establish a vacuum gradient of increasing pressure across the system from the first transfer chamber to the second transfer chamber.

3. The system of claim 1, wherein the PVD processing chamber has an annealing pedestal disposed therein.

4. The system of claim 3, wherein the PVD processing chamber has a sputtering source of a material selected from the group of cobalt, titanium, tantalum, tungsten, molybdenum, platinum, nickel, iron, niobium, palladium, and combinations thereof.

5. The system of claim 1, wherein the annealing chamber is a rapid thermal annealing chamber.

6. The system of claim 1, wherein the first substrate transfer chamber includes a pre-clean chamber disposed on the first transfer chamber.

7. The system of claim 6, wherein the first substrate transfer chamber includes a degas chamber.

8. The system of claim 7, wherein a pass-through chamber having vacuum pumps coupled thereto and a heating/cooling unit disposed therein is disposed between the first substrate transfer chamber and the second substrate transfer chamber.

9. The system of claim 1, wherein the first pressure is between about 1×

10<sup>−

5</sup> Torr and about 1×

10<sup>−

8</sup> Torr and the second pressure is between about 100 milliTorr and about 5 Torr.

10. The system of claim 1, wherein either the first transfer chamber or the second transfer chamber includes an etch chamber.

11. A method of processing a substrate, comprising:

positioning a substrate having a silicon material disposed thereon with patterned feature definitions formed therein in a substrate processing system;

depositing a first metal layer on the substrate surface in a first processing chamber disposed on the processing system by a physical vapor deposition technique, a chemical vapor deposition technique, or an atomic layer deposition technique;

forming a metal silicide layer by reacting the silicon material and the first metal layer; and

depositing a second metal layer in situ on the substrate in a second processing chamber disposed on the processing system by a chemical vapor deposition technique.

12. The method of claim 11, wherein forming the metal silicide layer comprises annealing the substrate in situ prior to transferring the substrate to the second processing chamber.

13. The method of claim 12, wherein forming the metal silicide layer comprises exposing the substrate to a temperature between about 300°

C. and about 900°

C. prior to depositing the second metal layer in the second processing chamber.

14. The method of claim 12, wherein forming the metal silicide layer comprises depositing the second metal layer by the chemical vapor deposition technique at a temperature between about 300°

C. and about 900°

C.

15. The method of claim 12, wherein annealing the substrate comprises annealing the substrate in the first processing chamber or a vacuum annealing chamber prior to depositing the second metal layer in the second processing chamber.

16. The method of claim 12, wherein annealing the substrate in situ comprises annealing the substrate at a temperature between about 300°

C. and about 900°

C. without breaking vacuum.

17. The method of claim 11, wherein forming the metal silicide layer comprises annealing the substrate in situ at a first temperature and annealing the substrate at a second temperature greater than the first temperature without breaking vacuum prior to depositing the second metal layer in the second processing chamber.

18. The method of claim 17, wherein the substrate is etched to remove unreacted metal after the annealing the substrate at a first temperature and prior to the annealing the substrate at a second temperature.

19. The method of claim 17, wherein the first temperature is between about 300°

C. and about 600°

C. and the second temperature is between about 400°

C. and about 900°

C.

20. The method of claim 17, wherein the annealing the substrate in situ comprises annealing the substrate at the first temperature in the deposition chamber and annealing the substrate at the second temperature in a vacuum annealing chamber without breaking vacuum in a processing system.

21. The method of claim 17, wherein annealing the substrate in situ comprises annealing the substrate at the first temperature in a first annealing chamber and then annealing the substrate at the second temperature in a second annealing chamber without breaking vacuum in a processing system.

22. The method of claim 11, wherein the first metal layer comprises cobalt, titanium, tantalum, tungsten, molybdenum, platinum, nickel, iron, niobium, palladium, and combinations thereof.

23. The method of claim 11, wherein the first metal layer comprises cobalt, nickel, or combinations thereof and the second metal layer comprises tungsten.

24. The method of claim 11, wherein a layer of barrier material is deposited on the first metal layer prior to depositing the second metal layer.

25. The method of claim 11, further comprising annealing the substrate after depositing the second metal layer.

26. The method of claim 11, further comprising treating the substrate surface to remove oxide formation by a hydrofluoric dipping technique or a plasma etch technique.

27. A method of processing a substrate, comprising:

positioning a substrate having feature definitions formed in a silicon-containing material in a substrate processing system;

depositing a metal layer on the silicon-containing material in the feature definitions, wherein the metal layer comprises cobalt, nickel, or combinations thereof; and

depositing a tungsten layer on the metal layer by a chemical vapor deposition technique at a temperature sufficient to form a metal silicide layer at an interface of the silicon-containing material and the metal layer.

28. The method of claim 27, wherein the tungsten layer is deposited at a temperature between about 300°

C. and about 500°

C.

29. The method of claim 27, wherein the tungsten layer is deposited by an in situ process comprising:

depositing a silicon layer on the metal layer;

depositing a tungsten nucleation layer on the silicon layer; and

depositing bulk tungsten on the tungsten nucleation layer.

30. The method of claim 27, further comprising annealing the substrate after depositing the tungsten layer to substantially convert the metal layer to metal silicide.

31. The method of claim 30, wherein the annealing the substrate comprises exposing the substrate to a temperature between about 400°

C. and about 900°

C. and higher than the tungsten deposition temperature.

32. The method of claim 27, further comprising depositing a titanium nitride layer on the metal layer prior to depositing the tungsten layer.

33. The method of claim 27, wherein the deposition of the metal layer, the deposition of the tungsten layer, and the annealing are performed in the same processing system without breaking vacuum.

34. A method of processing a substrate, comprising:

positioning a substrate having feature definitions formed in a silicon-containing material in a substrate processing system;

depositing a metal layer on the silicon-containing material in the feature definitions in a physical vapor deposition chamber;

annealing the substrate in the physical vapor deposition chamber to form a metal silicide layer at an interface of the silicon-containing material and the metal layer;

annealing the substrate to substantially convert the metal layer to metal silicide; and

depositing a tungsten layer on the metal layer in a chemical vapor deposition chamber.

35. The method of claim 34, wherein the tungsten layer is deposited by a process comprising:

depositing a silicon layer on the metal layer;

depositing a tungsten nucleation layer on the silicon layer; and

depositing bulk tungsten on the tungsten nucleation layer.

36. The method of claim 34, wherein annealing the substrate in the physical vapor deposition chamber comprises exposing the substrate at a first temperature between about 300°

C. and about 600°

C.

37. The method of claim 34, wherein annealing the substrate to substantially convert the metal layer to metal silicide comprises exposing the substrate at a second temperature greater than the first temperature without breaking vacuum prior to depositing the tungsten layer, wherein the second temperature is between about 400°

C. and about 90°

C.

38. The method of claim 34, wherein annealing the substrate to substantially convert the metal layer to metal silicide comprises exposing the substrate at a second temperature greater than the first temperature after depositing the tungsten layer without breaking vacuum, wherein the second temperature is between about 400°

C. and about 900°

C.

39. The method of claim 34, wherein the substrate is etched to remove unreacted metal after annealing the substrate in situ in the physical vapor deposition chamber to form a metal silicide layer.

40. The method of claim 34, wherein the first metal layer comprises cobalt, titanium, tantalum, tungsten, molybdenum, platinum, nickel, iron, niobium, palladium, and combinations thereof.

41. The method of claim 34, further comprising depositing a barrier layer material on the metal layer prior to depositing the tungsten layer.

42. The method of claim 34, further comprising treating the substrate surface to remove oxide formation by a hydrofluoric dipping technique or a plasma etch technique.

43. A method of processing a substrate, comprising:

positioning a substrate having a silicon material disposed thereon with patterned feature definitions formed therein in a first processing chamber;

exposing the substrate to a plasma cleaning process in a first processing chamber;

depositing a cobalt layer on the substrate surface and in the feature definitions by a physical vapor deposition technique in a second processing chamber;

annealing the substrate at a first temperature in the second processing chamber to partially form a cobalt silicide layer;

annealing the substrate at a second temperature greater than the first temperature in a third processing chamber to substantially form the cobalt silicide layer; and

depositing a tungsten layer on the cobalt silicide layer by a chemical vapor deposition technique in a fourth processing chamber, wherein the first, second, third, and fourth processing chamber are disposed on one vacuum processing system.

44. The method of claim 43, wherein the first temperature is between about 300°

C. and about 600°

C. and the second temperature is between about 400°

C. and about 900°

C.

45. The method of claim 43, wherein the tungsten layer is deposited by an in situ process comprising:

depositing a silicon layer on the metal layer;

depositing a tungsten nucleation layer on the silicon layer; and

depositing bulk tungsten on the tungsten nucleation layer.

46. The method of claim 43, further comprising removing unreacted metal after annealing the substrate at a first temperature and prior to annealing the substrate at a second temperature.

47. The method of claim 43, further comprising depositing a layer of barrier material is deposited on the cobalt layer prior to depositing the tungsten layer.

48. The method of claim 43, further comprising treating the substrate surface to remove oxide formation by a hydrofluoric dipping technique or a plasma etch technique.

49. The method of claim 43, further comprising annealing the substrate following deposition of the tungsten layer.

50. A method of processing a substrate, comprising:

positioning a substrate having feature definitions formed in a silicon-containing material in a substrate processing system;

depositing a metal layer on the silicon-containing material in the feature definitions, wherein the metal layer comprises cobalt, nickel, or combinations thereof;

annealing the substrate at a first temperature to form a metal silicide layer;

depositing a tungsten layer on the metal layer by a chemical vapor deposition technique; and

annealing the substrate at a second temperature greater than the first temperature.

51. The method of claim 50, wherein the tungsten layer is deposited at a temperature between about 300°

C. and about 500°

C.

52. The method of claim 50, wherein the first temperature is between about 300°

C. and about 600°

C. and the second temperature is between about 400°

C. and about 900°

C.

53. The method of claim 50, wherein the tungsten layer is deposited in a chemical vapor deposition chamber by a process comprising:

depositing a silicon layer on the metal layer;

depositing a tungsten nucleation layer on the silicon layer; and

depositing bulk tungsten on the tungsten nucleation layer.

54. The method of claim 50, further comprising depositing a titanium nitride layer on the metal layer prior to depositing the tungsten layer.

55. The method of claim 50, wherein the deposition of the metal layer, the annealing at the first temperature, the deposition of the tungsten layer, and the annealing at the second temperature are performed in the same processing system without breaking vacuum.

56. The method of claim 50, wherein the first metal layer comprises cobalt, titanium, tantalum, tungsten, molybdenum, platinum, nickel, iron, niobium, palladium, and combinations thereof.