Method for depositing nanolaminate thin films on sensitive surfaces

• US 20050106877A1
• Filed: 10/19/2004
• Published: 05/19/2005
• Est. Priority Date: 10/15/1999
• Status: Active Grant

• Current Assignee: Kai-Erik Elers, Pekka Soininen, Saanila Ville, Sari Kaipio, Suvi Haukka
• Original Assignee: Kai-Erik Elers, Pekka Soininen, Saanila Ville, Sari Kaipio, Suvi Haukka
• Inventors: Soininen, Pekka, Elers, Kai-Erik, Haukka, Suvi, Kaipio, Sari, Saanila, Ville
• Granted Patent: US 7,329,590 B2
• Time in Patent Office: Days
• US Class Current: 438/689
• CPC Class Codes: C23C 16/32 Carbides
• CPC Class Codes: C23C 16/34 Nitrides C23C16/303 takes precedence
• CPC Class Codes: C23C 16/44 characterised by the method of coating C23C16/04 takes precedence
• CPC Class Codes: C23C 16/4401 Means for minimising impurities, e.g. dust, moisture or residual gas, in the reaction chamber
• CPC Class Codes: C23C 16/45525 Atomic layer deposition [ALD]
• CPC Class Codes: C23C 16/45529 specially adapted for making a layer stack of alternating different compositions or gradient compositions
• CPC Class Codes: C23C 16/45534 Use of auxiliary reactants other than used for contributing to the composition of the main film, e.g. catalysts, activators or scavengers
• CPC Class Codes: C30B 25/02 Epitaxial-layer growth
• CPC Class Codes: C30B 29/02 Elements
• CPC Class Codes: C30B 29/36 Carbides
• CPC Class Codes: C30B 29/38 Nitrides
• CPC Class Codes: H01L 21/28562 Selective deposition
• CPC Class Codes: H01L 21/28568 the conductive layers comprising transition metals H01L21/28518 takes 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 21/76877 Filling of holes, grooves or trenches, e.g. vias, with conductive material

Abstract

The present method provides tools for growing conformal metal nitride, metal carbide and metal thin films, and nanolaminate structures incorporating these films, from aggressive chemicals. The amount of corrosive chemical compounds, such as hydrogen halides, is reduced during the deposition of transition metal, transition metal carbide and transition metal nitride thin films on various surfaces, such as metals and oxides. Getter compounds protect surfaces sensitive to hydrogen halides and ammonium halides, such as aluminum, copper, silicon oxide and the layers being deposited, against corrosion. Nanolaminate structures (20) incorporating metal nitrides, such as titanium nitride (30) and tungsten nitride (40), and metal carbides, and methods for forming the same, are also disclosed.

Claims

1. A method of depositing a material on a substrate in a reaction space, the substrate including a surface susceptible to halide attack, the method comprising providing alternated pulses of reactants in a plurality of deposition cycles, each cycle comprising:

supplying a first reactant to chemisorb no more than about one monolayer of a halide-terminated species over the surface;

removing excess first reactant and reaction by-product from the reaction space; and

gettering halides from the monolayer by exposure to a boron compound prior to repeating the cycle.

2. The method of claim 1, wherein the material is a metal nitride.

3. The method of claim 1, wherein the material is a metal carbide.

4. The method of claim 1, wherein the first reactant comprises a metal halide.

5. The method of claim 1, further comprising supplying a second reactant to react with the species after gettering halides.

6. The method of claim 5, wherein the second reactant is a hydrogen bearing reactant.

7. The method of claim 5, wherein the second reactant comprises a source of nitrogen and the material comprises a transition metal nitride.

8. The method of claim 5, wherein the second reactant is ammonia.

9. The method of claim 1, further comprising supplying a carbon source to react with the species and the material comprises a transition metal carbide.

10. The method of claim 1, wherein the material comprises a thin film within a nanolaminate stack.

11. The method of claim 10, wherein the nanolaminate stack is a diffusion barrier in an integrated circuit.

12. The method of claim 1, wherein the surface comprises a material selected from the group consisting of aluminum, copper, silicon, silicon oxide, coated silicon, low-k materials, transition metal nitrides, metal oxides, and silicon nitride.

13. The method of claim 1, wherein the surface comprises copper.

14. The method of claim 1, wherein gettering comprises reducing.

15. The method of claim 1, wherein the boron compound comprises triethyl boron (TEB).

16. An atomic layer deposition (ALD) type process for depositing a metal nitride thin film on a substrate comprising a copper surface, the method comprising exposing the substrate to a metal halide precursor that does not etch or corrode the copper surface.

17. The process of claim 16, wherein the metal nitride thin film comprises tantalum nitride.

18. The process of claim 16, wherein the metal nitride thin film is a diffusion barrier in an integrated circuit.

19. The process of claim 16, wherein the metal halide is tantalum fluoride.

20. The process of claim 16, wherein the metal halide is selected from the group consisting of hafnium bromide and niobium fluoride.

21. The process of claim 16, wherein the ALD type process comprises providing alternating pulses of reactants in a plurality of deposition cycles, each cycle comprising:

supplying the metal precursor to chemisorb no more than about one monolayer over the substrate surface;

removing excess metal precursor;

supplying a nitrogen source and removing excess nitrogen source.

22. The process of claim 21, wherein the nitrogen source is selected from the group consisting of ammonia (NH₃), nitrogen radicals and excited species of nitrogen.

23. The process of claim 16, wherein the copper surface is the surface of a metallization layer.

24. The process of claim 16, wherein the substrate comprises a dual damascene structure.

25. A method for depositing tantalum nitride on a substrate in a reaction space, the method comprising providing alternating pulses of reactants in a plurality of deposition cycles, each cycle comprising:

supplying TaF₅ to chemisorb no more than about one monolayer over the surface;

removing excess TaF₅;

supplying a nitrogen containing reactant; and

removing excess nitrogen containing reactant, wherein the substrate comprises a surface comprising a material selected from the group consisting of aluminum, copper, silicon oxide, silicon, silicon nitride and low-k materials.

26. The method of claim 25, wherein the nitrogen containing reactant is selected from the group consisting of ammonia, nitrogen radicals and excited species of nitrogen.

27. The method of claim 26, wherein the nitrogen containing reactant is ammonia.

28. The method of claim 25, wherein the surface comprises copper.