Systems and methods of forming refractory metal nitride layers using disilazanes

• US 20070166999A1
• Filed: 02/28/2007
• Published: 07/19/2007
• Est. Priority Date: 08/28/2002
• Status: Active Grant

• Current Assignee: Micron Technology, Inc.
• Original Assignee: Micron Technology, Inc.
• Inventors: Vaartstra, Brian
• Granted Patent: US 7,560,393 B2
• Time in Patent Office: Days
• US Class Current: 438/627
• CPC Class Codes: C23C 16/34 Nitrides C23C16/303 takes precedence
• CPC Class Codes: C23C 16/45523 Pulsed gas flow or change of composition over time
• CPC Class Codes: C23C 16/45531 specially adapted for making ternary or higher compositions
• CPC Class Codes: C23C 16/45553 characterized by the use of precursors specially adapted for ALD
• 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 21/28562 Selective deposition
• CPC Class Codes: H01L 21/76841 Barrier, adhesion or liner layers
• CPC Class Codes: H01L 21/76864 Thermal treatment
• CPC Class Codes: H01L 28/55 with a dielectric comprising a perovskite structure material
• CPC Class Codes: H01L 28/60 Electrodes

Abstract

A method of forming (and apparatus for forming) refractory metal nitride layers (including silicon nitride layers), such as a tantalum (silicon) nitride barrier layer, on a substrate by using a vapor deposition process with a refractory metal precursor compound, a disilazane, and an optional silicon precursor compound.

Claims

1. A vapor deposition method comprising:

providing a vapor comprising one or more refractory metal precursor compounds of the formula MY_n, (Formula I), wherein M is a refractory metal, each Y is independently a halogen atom, and n is an integer selected to match the valence of the metal M;

providing a vapor comprising one or more disilazanes of the formula (R)_xH_3-xSiNHSi(R)_xH_3-x, wherein each R is independently an organic group, and x is 1 to 3; and

contacting the vapors comprising the one or more refractory metal precursor compounds and the one or more disilazanes with a substrate to form a refractory metal nitride layer on one or more surfaces of the substrate.

2. The method of claim 1 wherein Y is independently selected from the group consisting of F, Cl, I, and combinations thereof.

3. The method of claim 2 wherein each Y is a fluorine atom.

4. The method of claim 3 wherein M is selected from the group consisting of Ti, Nb, Ta, Mo, and W.

5. A vapor deposition method comprising:

providing a vapor comprising one or more refractory metal precursor compounds of the formula MY_n (Formula I), wherein M is a refractory metal, each Y is independently a halogen atom, and n is an integer selected to match the valence of the metal M;

providing a vapor comprising one or more disilazanes of the formula (R)_xH_3-xSiNHSi(R)_xH_3-x, wherein each R is independently an organic group, and x is 1 to 3;

providing a vapor comprising one or more silicon precursor compounds other than the one or more disilazanes; and

contacting the vapors comprising the one or more refractory metal precursor compounds, the one or more disilazanes, and the one or more silicon precursor compounds other than the one or more disilazanes with a substrate to form a refractory metal silicon nitride layer on one or more surfaces of the substrate.

6. The method of claim 5 further comprising providing one or more reaction gases other than the one or more disilazanes and the one or more silicon precursor compounds other than the one or more disilazanes, and contacting the one or more reaction gases with the substrate.

7. The method of claim 5 wherein the formed layer is a tantalum silicon nitride layer.

8. The method of claim 5 wherein the formed layer has a thickness of about 10 Å

to about 100 Å

.

9. A vapor deposition method comprising:

providing a vapor comprising one or more refractory metal precursor compounds of the formula MY_n (Formula I), wherein M is a refractory metal, each Y is independently a halogen atom, and n is an integer selected to match the valence of the metal M;

providing a vapor comprising one or more disilazanes of the formula (R)_xH_3-xSiNHSi(R)_xH_3-x, wherein each R is independently an organic group, and x is 1 to 3;

providing a vapor comprising one or more metal-containing precursor compounds having a formula different than Formula I; and

contacting the vapors comprising the one or more refractory metal precursor compounds of the formula (Formula I), the one or more disilazanes, and the one or more metal-containing precursor compounds having a formula different than Formula I, with a substrate to form a refractory metal nitride layer on one or more surfaces of the substrate.

10. The method of claim 9 wherein the substrate comprises a silicon-containing surface.

11. A method of manufacturing a semiconductor structure, the method comprising:

providing a vapor comprising one or more refractory metal precursor compounds of the formula MY_n (Formula I), wherein M is a refractory metal, each Y is independently a halogen atom, and n is an integer selected to match the valence of the metal M;

providing a vapor comprising one or more disilazanes of the formula (R)_xH_3-xSiNHSi(R)_xH_3-x, wherein each R is independently an organic group, and x is 1 to 3; and

contacting the vapors comprising the one or more refractory metal precursor compounds and the one or more disilazanes with a semiconductor substrate or substrate assembly to form a refractory metal nitride layer on one or more surfaces of the semiconductor substrate or substrate assembly.

12. The method of claim 11 wherein the semiconductor substrate or substrate assembly is a silicon wafer.

13. The method of claim 11 wherein M is tantalum and n is 5.

14. The method of claim 11 wherein each R is independently selected from the group consisting of (C1-C6) organic compounds.

15. The method of claim 14 wherein each R is independently ethyl or methyl.

16. A method of manufacturing a semiconductor structure, the method comprising:

providing a vapor comprising one or more refractory metal precursor compounds of the formula MY_n (Formula I), wherein M is a refractory metal, each Y is independently a halogen atom, and n is an integer selected to match the valence of the metal M;

providing a vapor comprising one or more disilazanes of the formula (R)_xH_3-xSiNHSi(R)_xH_3-x, wherein each R is independently an organic group, and x is 1 to 3;

providing a vapor comprising one or more silicon precursor compounds other than the one or more disilazanes; and

directing the vapors comprising the one or more refractory metal precursor compounds, the one or more disilazanes, and the one or more silicon precursor compounds other than the one or more disilazanes to a semiconductor substrate or substrate assembly, to form a refractory metal silicon nitride layer on one or more surfaces of the semiconductor substrate or substrate assembly.

17. The method of claim 16 wherein the semiconductor substrate or substrate assembly comprises a silicon-containing surface.

18. The method of claim 16 wherein providing the vapors and directing the vapors is accomplished using a chemical vapor deposition process.

19. The method of claim 18 wherein the temperature of the semiconductor substrate or substrate assembly is about 100°

C. to about 600°

C.

20. The method of claim 18 wherein the semiconductor substrate or substrate assembly is in a deposition chamber having a pressure of about 0.1 torr to about 10 torr.

21. A method of manufacturing a semiconductor structure, the method comprising:

providing a vapor comprising one or more refractory metal precursor compounds of the formula MY_n (Formula I), wherein M is a refractory metal, each Y is independently a halogen atom, and n is an integer selected to match the valence of the metal M;

providing a vapor comprising one or more disilazanes of the formula (R)_xH_3-xSiNHSi(R)_xH_3-x, wherein each R is independently an organic group, and x is 1 to 3;

providing a vapor comprising the one or more metal-containing precursor compounds having a formula different than Formula I; and

directing the vapors comprising the one or more refractory metal precursor compounds of the formula (Formula I), the one or more disilazanes, and the one or more metal-containing precursor compounds having a formula different than Formula I, to a semiconductor substrate or substrate assembly to form a refractory metal nitride layer on one or more surfaces of the semiconductor substrate or substrate assembly.

22. The method of claim 21 wherein providing the vapors and directing the vapors is accomplished using an atomic layer deposition process comprising a plurality of deposition cycles.

23. The method of claim 22 wherein the temperature of the semiconductor substrate or substrate assembly is about 25°

C. to about 400°

C.

24. The method of claim 22 wherein the semiconductor substrate or substrate assembly is in a deposition chamber having a pressure or about 10⁻

4 torr to about 1 torr.

25. A vapor deposition method comprising:

contacting a vapor comprising one or more refractory metal precursor compounds with a substrate comprising a silicon-containing surface and allowing the one or more compounds to chemisorb on the silicon-containing surface, wherein the one or more refractory metal precursor compounds are of the formula MY_n (Formula I), wherein M is a refractory metal, each Y is independently a halogen atom, and n is an integer selected to match the valence of the metal M; and

contacting a vapor comprising one or more disilazanes with the substrate having the chemisorbed compounds thereon to form a refractory metal nitride barrier layer on one or more silicon-containing surfaces of the substrate, wherein the one or more disilazanes are of the formula (R)_xH_3-xSiNHSi(R)_xH_3-x, wherein each R is independently an organic group, and x is 1 to 3.

26. The method of claim 25 wherein the vapor deposition method is an atomic layer deposition process, and the refractory metal nitride barrier layer is formed by alternately introducing the one or more vaporized precursor compounds and one or more vaporized disilazanes during each deposition cycle.

27. A vapor deposition method comprising:

contacting a vapor comprising one or more refractory metal precursor compounds with a substrate comprising a silicon-containing surface and allowing the one or more compounds to chemisorb on the silicon-containing surface, wherein the one or more refractory metal precursor compounds are of the formula MY_n (Formula I), wherein M is a refractory metal, each Y is independently a halogen atom, and n is an integer selected to match the valence of the metal M;

contacting a vapor comprising one or more disilazanes with the substrate having the chemisorbed compounds thereon, wherein the one or more disilazanes are of the formula (R)_xH_3-xSiNHSi(R)_xH_3-x, wherein each R is independently an organic group, and x is 1 to 3; and

contacting a vapor comprising one or more silicon precursor compounds other than the one or more disilazanes with the substrate having the chemisorbed compounds thereon to form a refractory metal silicon nitride barrier layer on one or more silicon-containing surfaces of the substrate.

28. The method of claim 27 wherein the formed layer is a tantalum silicon nitride layer.

29. The method of claim 28 wherein the formed layer is a diffusion barrier layer.

30. A vapor deposition method comprising:

contacting a vapor comprising one or more refractory metal precursor compounds with a substrate comprising a silicon-containing surface and allowing the one or more compounds to chemisorb on the silicon-containing surface, wherein the one or more refractory metal precursor compounds are of the formula MY_n (Formula I), wherein M is a refractory metal, each Y is independently a halogen atom, and n is an integer selected to match the valence of the metal M;

contacting a vapor comprising one or more disilazanes with the substrate having the chemisorbed compounds thereon, wherein the one or more disilazanes are of the formula (R)_xH_3-xSiNHSi(R)_xH_3-x, wherein each R is independently an organic group, and x is 1 to 3; and

contacting one or more metal-containing precursor compounds having a formula different than Formula I with the substrate to form a refractory metal silicon nitride barrier layer on one or more silicon-containing surfaces of the substrate.

31. The method of claim 30 wherein the disilazane is tetramethyldisilazane (TMDS), (CH₃)₂HSiNHSiH(CH₃)₂, or hexamethyldisilazane.

32. The method of claim 31 wherein the disilazane is tetramethyldisilazane.

33. A method of forming a layer on a substrate, the method comprising:

contacting a vapor comprising one or more refractory metal precursor compounds with a semiconductor substrate or substrate assembly comprising a silicon-containing surface and allowing the one or more compounds to chemisorb on the silicon-containing surface, wherein the one or more refractory metal precursor compounds are of the formula MY_n (Formula I), wherein M is a refractory metal, each Y is independently a halogen atom, and n is an integer selected to match the valence of the metal M; and

contacting a vapor comprising one or more disilazanes with the semiconductor substrate or substrate assembly having the chemisorbed compounds thereon to form a refractory metal nitride barrier layer on one or more silicon-containing surfaces of the semiconductor substrate or substrate assembly, wherein the one or more disilazanes are of the formula (R)_xH_3-xSiNHSi(R)_xH_3-x, wherein each R is independently an organic group, and x is 1 to 3.