SILICON NITRIDE FILMS AND METHODS

• US 20110256734A1
• Filed: 04/11/2011
• Published: 10/20/2011
• Est. Priority Date: 04/15/2010
• Status: Abandoned Application

• Current Assignee: Novellus Systems Incorporated (Lam Research Corporation)
• Original Assignee: Novellus Systems Incorporated (Lam Research Corporation)
• Inventors: Henri, Jon, Sriram, Mandyam, van Schravendijk, Bart J., Hausmann, Dennis M.
• Application Number:
  US13/084,305
• Publication Number:
  US 20110256734A1
• Time in Patent Office: Days
• US Class Current: 438/776
• CPC Class Codes: C23C 16/045 Coating cavities or hollow spaces, e.g. interior of tubes; Infiltration of porous substrates
• CPC Class Codes: C23C 16/345 Silicon nitride
• CPC Class Codes: C23C 16/402 Silicon dioxide
• CPC Class Codes: C23C 16/45523 Pulsed gas flow or change of composition over time
• CPC Class Codes: C23C 16/4554 Plasma being used non-continuously in between ALD reactions C23C16/56 takes precedence
• CPC Class Codes: C23C 16/56 After-treatment
• CPC Class Codes: H01L 21/02164 the material being a silicon oxide, e.g. SiO2
• CPC Class Codes: H01L 21/0217 the material being a silicon nitride not containing oxygen, e.g. SixNy or SixByNz H01L21/02126 and H01L21/0214 take precedence
• CPC Class Codes: H01L 21/02274 in the presence of a plasma [PECVD]
• CPC Class Codes: H01L 21/0228 deposition by cyclic CVD, e.g. ALD, ALE, pulsed CVD
• CPC Class Codes: H01L 21/02348 treatment by exposure to UV light
• CPC Class Codes: H01L 21/28562 Selective deposition
• CPC Class Codes: H01L 21/67017 Apparatus for fluid treatment H01L21/67126, H01L21/6715 take precedence
• CPC Class Codes: H01L 21/6719 characterized by the construction of the processing chambers, e.g. modular processing chambers
• CPC Class Codes: H01L 21/67201 characterized by the construction of the load-lock chamber
• CPC Class Codes: H01L 21/76224 using trench refilling with dielectric materials trench filling with polycristalline silicon H01L21/763; together with vertical isolation, e.g. trench refilling in a SOI substrate H01L21/76264
• CPC Class Codes: H01L 21/76825 by exposing the layer to particle radiation, e.g. ion implantation, irradiation with UV light or electrons etc. plasma treatment H01L21/76826
• CPC Class Codes: H01L 21/76826 by contacting the layer with gases, liquids or plasmas
• CPC Class Codes: H01L 21/76829 characterised by the formation of thin functional dielectric layers, e.g. dielectric etch-stop, barrier, capping or liner layers
• CPC Class Codes: H01L 21/76837 Filling up the space between adjacent conductive structures; Gap-filling properties of dielectrics
• CPC Class Codes: H01L 21/76898 : formed through a semiconductor substrate

Abstract

Described are methods of making SiN materials on substrates, particularly SiN thin films on semiconductor substrates. Improved SiN films made by the methods are also included.

Claims

1. A method of forming a silicon nitride material on a substrate, comprising:

(a) providing the substrate in a reaction chamber;

(b) continuously exposing the substrate to a vapor phase flow of a nitrogen-containing reactant wherein the nitrogen-containing reactant is adsorbed onto the surface of the substrate;

(c) periodically exposing the substrate to a vapor phase flow of a silicon-containing reactant wherein the silicon-containing reactant is adsorbed onto the surface of the substrate; and

(d) periodically igniting a plasma in the reaction chamber when the vapor phase flow of the silicon-containing reactant has ceased.

2. The method of claim 1, further comprising continuously flowing a carrier gas through the reaction chamber.

3. The method of claim 1 or 2, further comprising purging to remove unabsorbed silicon-containing reactant after (c) but before (d).

4. The method of claim 1, wherein the substrate is a semiconductor wafer.

5. The method of claim 4, further comprising repeating (b) through (d) to form a conformal layer on the semiconductor wafer between about 1 nm and about 100 nm thick.

6. The method of claim 1, wherein the silicon-containing reactant is selected from the group consisting of a silane, a halosilane and an aminosilane, and mixtures thereof.

7. The method of claim 1, wherein the nitrogen-containing reactant is selected from the group consisting of ammonia, a hydrazine, an amine and mixtures thereof.

8. The method of claim 7, wherein the nitrogen-containing reactant comprises a C_1-10alkyl amine.

9. The method of claim 8, wherein the C_1-10 alkyl amine is tert-butyl amine.

10. The method of claim 8, wherein the silicon-containing reactant is a monochlorosilane or a dichlorosilane.

11. The method of claim 4, wherein the semi-conductor wafer is heated to between about 50°

C. and about 550°

C.

12. A method of forming a silicon nitride material on a substrate, comprising:

(a) forming a silicon nitride film on the substrate, said formation comprising;

(i) providing the substrate in a reaction chamber;

(ii) exposing the substrate to a silicon-containing reactant in the vapor phase so that the silicon-containing reactant is adsorbed onto the surface of the substrate;

(iii) exposing the substrate to a nitrogen-containing reactant in the vapor phase so that the nitrogen-containing reactant is adsorbed onto the surface of the substrate;

(iv) igniting a plasma while the nitrogen-containing reactant is present in the vapor phase;

and then,

(b) exposing the silicon nitride film to a hydrogen containing plasma to remove at least some carbon content of the silicon nitride film.

13. The method of claim 12, wherein the substrate is a semiconductor wafer.

14. The method of claim 12, wherein (ii) is performed prior to (iii).

15. The method of claim 12, wherein (iii) is performed prior to (ii).

16. The method of claim 13, wherein (a) is repeated two or more times prior to (b).

17. The method of claim 13, further comprising repeating (a) and (b) to form a conformal layer on the semiconductor wafer between about 1 nm and about 100 nm thick.

18. The method of claim 12, wherein the silicon-containing reactant is selected from the group consisting of a silane, a halosilane and an aminosilane, and mixtures thereof.

19. The method of claim 12, wherein the nitrogen-containing reactant comprises a C_1-10alkyl amine.

20. The method of claim 18, wherein the silicon-containing reactant is a chlorosilane.

21. The method of claim 12, further comprising continuously flowing a carrier gas through the reaction chamber after (i).

22. The method of claim 13, wherein the semi-conductor wafer is heated to between about 50°

C. and about 550°

C.

23. A method of forming a silicon nitride material on a substrate, comprising:

(a) providing the substrate in a reaction chamber;

(b) providing a carrier gas flow through the reaction chamber;

(c) exposing the substrate to a vapor phase flow of a nitrogen-containing reactant wherein the nitrogen-containing reactant is adsorbed onto the surface of the substrate and then purging the reaction chamber;

(d) exposing the substrate to a vapor phase flow of a silicon-containing reactant wherein the silicon-containing reactant is adsorbed onto the surface of the substrate;

(e) igniting a plasma in the reaction chamber after the vapor phase flow of the silicon-containing reactant has ceased; and

(f) heating the substrate to between about 200°

C. and about 550°

C.;

wherein at least one of the nitrogen-containing reactant and the silicon-containing reactant bears one or more of a thermally removable group, wherein said thermally removable group decomposes at between about 200°

C. and about 550°

C.

24. The method of claim 23, wherein the thermally removable group is according to Formula II:

25. The method of claim 23, wherein the substrate is a semiconductor wafer.

26. The method of claim 25, further comprising repeating (b) through (e) to form a conformal layer on the semiconductor wafer between about 1 nm and about 100 nm thick.

27. The method of claim 23, wherein (f) is performed throughout (b) through (e).

28. The method of claim 23, wherein the silicon-containing reactant is selected from the group consisting of a silane, a halosilane and an aminosilane, and mixtures thereof.

29. The method of claim 23, wherein the nitrogen-containing reactant is selected from the group consisting of ammonia, a hydrazine, an amine and mixtures thereof.

30. The method of claim 29, wherein the nitrogen-containing reactant is a C_1-10 alkyl amine according to formula I:

31. The method of claim 30, wherein the C_1-10 alkyl amine is selected from the group consisting of isopropylamine, cyclopropylamine, sec-butylamine, tert-butyl amine, cyclobutylamine, isoamylamine, 2-methylbutan-2-amine and thexylamine.

32. The method of claim 31, wherein the C_1-10 alkyl amine is tert-butyl amine.

33. The method of claim 29, wherein the silicon-containing reactant is a chlorosilane.

34. The method of claim 32, wherein the semi-conductor wafer is heated to between about 450°

C. and about 500°

C.

35. An apparatus for depositing a silicon nitride film on a semiconductor wafer, the apparatus comprising:

(a) a reaction chamber;

(b) a source of activation energy to form the silicon nitride film;

(c) a reactant inlet; and

(d) a controller comprising instructions for;

continuously flowing a nitrogen-containing reactant into the reaction chamber during a deposition cycle;

periodically flowing a silicon-containing reactant into the reaction chamber during the deposition cycle;

periodically igniting a plasma in the reaction chamber when the flow of the silicon-containing reactant has ceased.

36. The apparatus of claim 35, wherein the source of activation energy is a plasma generator.

37. The apparatus of claim 35, further including a vacuum port.

38. The apparatus of claim 36, wherein the plasma generator comprises induction coils and/or a microwave source.

39. An apparatus for depositing a silicon nitride film on a semiconductor wafer, the apparatus comprising:

(a) a reaction chamber;

(b) a source of activation energy to form the silicon nitride film;

(c) a reactant inlet; and

(d) a controller comprising instructions for;

flowing a nitrogen-containing reactant into the reaction chamber during a deposition cycle;

flowing a silicon-containing reactant into the reaction chamber during the deposition cycle;

periodically igniting a plasma in the reaction chamber when the flow of the silicon-containing reactant has ceased and while the nitrogen-containing reactant is present in the vapor phase in the reaction chamber.

40. The apparatus of claim 39, wherein the source of activation energy is a plasma generator.

41. The apparatus of claim 39, further including a vacuum port.

42. The apparatus of claim 40, wherein the plasma generator comprises induction coils and/or a microwave source.