Method for low-temperature organic chemical vapor deposition of tungsten nitride, tungsten nitride films and tungsten nitride diffusion barriers for computer interconnect metallization

• US 20030198587A1
• Filed: 04/28/2003
• Published: 10/23/2003
• Est. Priority Date: 02/12/1999
• Status: Active Grant

• Current Assignee: Gelest, Inc. (Mitsubishi Chemical Group Corp.), The Research Foundation for The State University of New York (State University of New York)
• Original Assignee: Gelest, Inc. (Mitsubishi Chemical Group Corp.), The Research Foundation for The State University of New York (State University of New York)
• Inventors: Arkles, Barry C., Kaloyeros, Alain E.
• Granted Patent: US 6,884,466 B2
• Time in Patent Office: Days
• US Class Current: 423/409
• CPC Class Codes: C01B 21/062 with chromium, molybdenum or tungsten
• CPC Class Codes: C01P 2002/72 by d-values or two theta-values, e.g. as X-ray diagram
• CPC Class Codes: C01P 2002/77 by unit-cell parameters, atom positions or structure diagrams
• CPC Class Codes: C01P 2004/03 obtained by SEM
• CPC Class Codes: C01P 2004/04 obtained by TEM, STEM, STM or AFM
• CPC Class Codes: C01P 2006/10 Solid density
• CPC Class Codes: C01P 2006/40 Electric properties
• CPC Class Codes: C23C 16/34 Nitrides C23C16/303 takes precedence

Abstract

Processes for producing tungsten nitride and tungsten nitride films are provided in which a tungsten carbonyl compound and a nitrogen-containing reactant gas are reacted at a temperature below about 600° C. Tungsten nitride precursors are also included which comprise a tungsten carbonyl compound capable of forming a tungsten nitride film in the presence of a nitrogen-containing reactant gas at a temperature of less than about 600° C. A process for forming a film by atomic layer deposition is also provided which includes introducing into a substrate having a surface into a deposition chamber and heating the substrate to a temperature sufficient to allow adsorption of a tungsten source precursor or an intermediate of a tungsten source precursor, introducing a tungsten source precursor into the deposition chamber by pulsing for a period of time sufficient to form a self-limiting monolayer of the source precursor or an intermediate of the tungsten source precursor intermediate, introducing an inert gas into the deposition chamber by pulsing the inert gas to purge the deposition to remove the tungsten nitride precursor in the gas phase, introducing a nitrogen-containing gas into the deposition chamber by pulsing to react with the adsorbed precursor monolayer on the substrate surface and to form a first tungsten nitride atomic layer on the substrate surface. An inert gas may then introduced into the deposition chamber for a period of time sufficient to remove the unreacted nitrogen-containing gas and reaction byproducts from the deposition chamber. The entire pulsing sequence including precursor, inert gas, nitrogen-containing gas may be repeated until a film with a desired thickness is achieved.

Claims

1. A process for the production of tungsten nitride comprising reacting a tungsten carbonyl compound with a nitrogen-containing gas at a temperature below about 600°

C.

2. The process for production of tungsten nitride according to claim 1, wherein the nitrogen-containing gas is ammonia.

3. The process for the production of tungsten nitride according to claim 1, wherein the tungsten nitride has a formula WN_x, wherein 0.1≦

x≦

2.0.

4. The process for the production of tungsten nitride according to claim 1, further comprising reacting the tungsten carbonyl compound with ammonia in the presence of hydrogen.

5. The process for the production of tungsten nitride according to claim 1, wherein the temperature is from about 200°

C. to about 350°

C.

6. The process for the production of tungsten nitride according to claim 5, wherein the temperature is from about 200°

C. to about 275°

C.

7. The process for the production of tungsten nitride according to claim 1, wherein the tungsten carbonyl compound is a compound according to formula (I):

W(CO)<sub>(6−

n)</sub>X_n  

 

(I)

wherein X is a two-electron donor or a ligand selected from the group consisting of ammonia, amine, carbonyl and halogen, and n is 0 or 1.

8. A process for the production of a tungsten nitride film comprising reacting a tungsten carbonyl compound with a nitrogen-containing gas at a temperature below about 600°

C.

9. The process for the production of a tungsten nitride film according to claim 8, wherein the nitrogen-containing gas is ammonia, and the process further comprises introducing the tungsten carbonyl into a deposition chamber having a substrate, wherein the substrate temperature is from about 200°

C. to about 600°

C., and introducing the ammonia into the deposition chamber separately from the tungsten carbonyl compound prior to reacting the tungsten carbonyl compound and the ammonia.

10. The process for the production of a tungsten nitride film according to claim 9, wherein the substrate temperature is from about 200°

C. to about 275°

C. and the tungsten nitride film is amorphous.

11. The process for the production of a tungsten nitride film according to claim 8, wherein the tungsten nitride film has a formula WN_x, wherein 0.1≦

x≦

2.0.

12. The process for the production of a tungsten nitride film according to claim 8, wherein the tungsten carbonyl compound has the following formula (I):

W(CO)<sub>(6−

n)</sub>X_n  

 

(I)

wherein X is a two-electron donor or a ligand selected from the group consisting of ammonia, amine, carbonyl and halogen, and n is 0 or 1.

13. A process for the chemical vapor deposition of a tungsten nitride film onto a substrate, comprising

(a) introducing into a deposition chamber:

(i) a substrate;

(ii) a tungsten carbonyl compound in a vapor state; and

(iii) at least one nitrogen-containing gas; and

(b) maintaining a substrate temperature of from about 200°

C. to about 600°

C. for a period of time sufficient to deposit a tungsten nitride film on the substrate.

14. The process for the chemical vapor deposition of a tungsten nitride film onto a substrate according to claim 13, wherein the tungsten carbonyl compound has the following formula (I):

W(CO)<sub>(6−

n)</sub>X_n  

 

(I)

wherein X is a two-electron donor or a ligand selected from the group consisting of ammonia, amine, carbonyl and halogen, and n is 0 or 1.

15. The process for the chemical vapor deposition of a tungsten nitride film onto a substrate according to claim 14, wherein the nitrogen-containing reactant gas is ammonia.

16. The process for the chemical vapor deposition of a tungsten nitride film onto a substrate according to claim 15, further comprising introducing hydrogen to the deposition chamber.

17. The process for the chemical vapor deposition of a tungsten nitride film onto a substrate according to claim 14, wherein the substrate temperature is from about 200°

C. to about 350°

C.

18. The process for the chemical vapor deposition of a tungsten nitride film onto a substrate according to claim 17, wherein the substrate temperature is from about 200°

C. to about 250°

C.

19. A tungsten nitride precursor comprising a tungsten carbonyl compound, wherein the precursor is capable of forming a tungsten nitride film in the presence of a nitrogen-containing reactant gas at a temperature of less than about 600°

C.

20. The tungsten nitride precursor according to claim 19, wherein the tungsten carbonyl compound has the following formula (I):

W(CO)<sub>(6−

n)</sub>X_n  

 

(I)

wherein X is a two-electron donor or a ligand selected from the group consisting of ammonia, amine, carbonyl and halogen, and n is 0 or 1.

21. The tungsten nitride precursor according to claim 20, wherein the tungsten carbonyl compound is tungsten hexacarbonyl.

22. A tungsten nitride film having an electrical resistance of less than about 600 μ

Ω

/cm, wherein the film is a reaction product of a tungsten carbonyl compound and a nitrogen-containing gas.

23. The tungsten nitride film according to claim 22, wherein the film is a reaction product of the tungsten carbonyl compound and the nitrogen-containing gas at temperatures below about 600°

C.

24. The tungsten nitride film according to claim 22, wherein the nitrogen-containing gas is ammonia and the tungsten carbonyl compound is tungsten hexacarbonyl.

25. A tungsten nitride coated substrate, comprising a substrate coated on at least one side with a tungsten nitride film, wherein the tungsten nitride film has an electrical resistance of less than about 600 μ

Ω

/cm and is a reaction product of a tungsten carbonyl compound and a nitrogen-containing gas.

26. A process for forming a film by atomic layer deposition, comprising

(a) introducing into a deposition chamber a substrate having a surface and heating the substrate to a temperature sufficient to allow adsorption of a tungsten source precursor or an intermediate of a tungsten source precursor;

(b) introducing a tungsten source precursor into the deposition chamber by pulsing the tungsten source precursor to expose the heated substrate surface to the tungsten source precursor for a period of time sufficient to form a self-limiting monolayer of the source precursor or an intermediate of the tungsten source precursor intermediate on the substrate surface;

(c) introducing an inert gas into the deposition chamber by pulsing the inert gas to purge the deposition chamber with an inert gas for a period of time sufficient to remove the tungsten nitride precursor in the gas phase but without removing adsorbed precursor in the monolayer;

(d) introducing a nitrogen-containing gas into the deposition chamber by pulsing the nitrogen-containing gas for a period of time sufficient to react with the adsorbed precursor monolayer on the substrate surface and to form a first tungsten nitride atomic layer on the substrate surface.

27. The process for forming a film by atomic layer deposition according to claim 26, wherein the precursor is a single source precursor in a vapor state.

28. The process for forming a film by atomic layer deposition according to claim 26, wherein the nitrogen-containing reactant gas is ammonia.

29. The process for forming a film by atomic layer deposition according to claim 26, further comprising (e) introducing an inert gas by pulsing the inert gas into the deposition chamber to purge the deposition chamber of the nitrogen-containing reactant gas.

30. The process for forming a film by atomic layer deposition according to claim 29, wherein steps (b) through (e) are repeated until a tungsten nitride film of a predetermined thickness is formed.

31. The process for forming a film by atomic layer deposition according to claim 26, wherein the precursor is a tungsten carbonyl compound, the reactant is a nitrogen-containing reactant gas and the film is a tungsten nitride film.

32. The process for forming a film by atomic layer deposition according to claim 26, wherein the tungsten source precursor is pulsed into the deposition chamber using at least one of a pressure-based delivery system and a temperature-based delivery system.

33. The process for forming a film by atomic layer deposition according to claim 26, wherein the inert gas is introduced into the deposition chamber using a mass flow controller or a valving system.

34. The process for forming a film by atomic layer deposition according to claim 26, wherein the precursor is pulsed into the deposition chamber with a transport gas.

35. The process for forming a film by atomic layer deposition according to claim 26, wherein a substrate temperature of the substrate is from about 50°

C. to about 450°

C.

36. The process for forming a film by atomic layer deposition according to claim 26, wherein the substrate temperature is from about 100°

C. to about 275°

C.