METHODS FOR DEPOSITING NICKEL FILMS AND FOR MAKING NICKEL SILICIDE AND NICKEL GERMANIDE

• US 20130115768A1
• Filed: 08/22/2012
• Published: 05/09/2013
• Est. Priority Date: 12/19/2008
• Status: Active Grant

• Current Assignee: ASM International NV
• Original Assignee: ASM International NV
• Inventors: Pore, Viljami J., Haukka, Suvi P., Blomberg, Tom E., Tois, Eva E.
• Granted Patent: US 9,379,011 B2
• Time in Patent Office: Days
• US Class Current: 438/664
• CPC Class Codes: H01L 21/28052 the conductor comprising a silicide layer formed by the silicidation reaction of silicon with a metal layer formed by metal ion implantation H01L21/28044
• CPC Class Codes: H01L 21/28518 the conductive layers comprising silicides H01L21/28537 takes precedence
• CPC Class Codes: H01L 21/28568 the conductive layers comprising transition metals H01L21/28518 takes precedence
• CPC Class Codes: H01L 21/321 After treatment
• CPC Class Codes: H01L 21/32133 by chemical means only
• CPC Class Codes: H01L 21/3215 Doping the layers
• CPC Class Codes: H01L 21/76843 formed in openings in a dielectric
• CPC Class Codes: H01L 21/76855 After-treatment introducing at least one additional element into the layer
• CPC Class Codes: H01L 21/76886 Modifying permanently or temporarily the pattern or the conductivity of conductive members, e.g. formation of alloys, reduction of contact resistances
• CPC Class Codes: H01L 29/456 on silicon
• CPC Class Codes: H01L 29/665 using self aligned silicidation, i.e. salicide formation of conductive layers comprising silicides H01L21/28518
• CPC Class Codes: H01L 29/78 with field effect produced by an insulated gate H01L29/7725, H01L29/775, H01L29/778 take precedence

Abstract

In one aspect, methods of silicidation and germanidation are provided. In some embodiments, methods for forming metal silicide can include forming a non-oxide interface, such as germanium or solid antimony, over exposed silicon regions of a substrate. Metal oxide is formed over the interface layer. Annealing and reducing causes metal from the metal oxide to react with the underlying silicon and form metal silicide. Additionally, metal germanide can be formed by reduction of metal oxide over germanium, whether or not any underlying silicon is also silicided. In other embodiments, nickel is deposited directly and an interface layer is not used. In another aspect, methods of depositing nickel thin films by vapor phase deposition processes are provided. In some embodiments, nickel thin films are deposited by ALD. Nickel thin films can be used directly in silicidation and germanidation processes.

Claims

1. A method of depositing a nickel thin film on a substrate by multiple cycles of a vapor deposition process, each cycle comprising alternately and sequentially contacting a substrate in a reaction space with a vapor phase nickel precursor and a second precursor, wherein in each cycle a layer of nickel precursor is formed on the substrate surface and the second reactant reacts with the nickel precursor to form a nickel thin film.

2. The method of claim 1, wherein no more than about one monolayer of the nickel precursor is formed on the substrate surface in each cycle.

3. The method of claim 1, wherein the nickel precursor is selected from the group consisting of nickel betadiketonate compounds, nickel betadiketiminato compounds, nickel aminoalkoxide compounds, nickel amidinate compounds, nickel cyclopentadienyl compounds, nickel carbonyl compounds and combinations thereof.

4. The method of claim 1, wherein the second reactant is selected from hydrogen, forming gas and organic reducing agents.

5. An atomic layer deposition-type process for forming an elemental Ni thin film on a substrate in a reaction chamber comprising multiple Ni deposition cycles, each deposition cycle comprising:

providing a first vapor phase reactant pulse comprising a first Ni precursor into the reaction chamber to form a layer of the Ni precursor on the substrate;

removing excess first reactant from the reaction chamber;

providing a second vapor phase reactant pulse to the reaction chamber such that the second reactant reacts with the first Ni precursor on the substrate in a self-limiting manner to form Ni; and

removing excess second reactant and reaction byproducts, if any, from the reaction chamber.

6. The method of claim 5, wherein the first Ni precursor is selected from the group consisting of nickel betadiketonate compounds, nickel betadiketiminato compounds, nickel aminoalkoxide compounds, nickel amidinate compounds, nickel cyclopentadienyl compounds, nickel carbonyl compounds and combinations thereof.

7. The method of claim 5, wherein the first nickel precursor is bis(4-N-ethylamino-3-penten-2-N-ethyliminato)nickel (II)

8. The method of claim 5, wherein the second reactant is selected from hydrogen and forming gas.

9. The method of claim 5, wherein the second reactant is an organic reducing agent.

10. The method of claim 9, wherein the organic reducing agent comprises at least one functional group selected from the group consisting of alcohol (—

OH), aldehyde (—

CHO), or carboxylic acid (—

COOH).

11. The method of claim 5, additionally comprising contacting the substrate with a third reactant.

12. The method of claim 11, wherein the third reactant is selected from organic reducing agents, hydrogen and forming gas.

13. An ALD-type process for depositing Ni thin films on a substrate in a reaction space comprising multiple Ni deposition cycles, each deposition cycle comprising:

providing a first vapor phase reactant pulse comprising a first Ni precursor into the reaction space to form a layer of the Ni precursor on the substrate;

removing excess first reactant from the reaction space;

providing a second vapor phase reactant pulse to the reaction space, wherein the second reactant is an organic reducing agent;

removing excess second reactant and reaction byproducts, if any, from the reaction space; and

providing a third vapor phase reactant pulse to the reaction space, wherein the third reactant is hydrogen or forming gas; and

removing excess third reactant and reaction byproducts, if any, from the reaction space.

14. The method of claim 13, wherein the first Ni precursor is selected from the group consisting of nickel betadiketonate compounds, nickel betadiketiminato compounds, nickel aminoalkoxide compounds, nickel amidinate compounds, nickel cyclopentadienyl compounds, nickel carbonyl compounds and combinations thereof.

15. The method of claim 14, wherein the first Ni precursor has the formula X(acac)_y or X(thd)_y, where X is a metal, y is from about 2 to about 3 and thd is 2,2,6,6-tetramethyl-3,5-heptanedionato.

16. The method of claim 13 wherein the first nickel precursor is bis(4-N-ethylamino-3-penten-2-N-ethyliminato)nickel (II)

17. The method of claim 13, wherein the organic reducing agent is provided after the Ni precursor but before the hydrogen or forming gas.

18. The method of claim 13, wherein the organic reducing agent is provide after the Ni precursor and after the hydrogen or forming gas.

19. A method for silicidation, comprising:

providing a substrate having at least one exposed silicon region;

depositing a nickel thin film over the exposed silicon region; and

heating the substrate to form a nickel silicide film.

20. The method of claim 19, wherein the nickel thin film is deposited by an ALD-type process.

21. The method of claim 20, wherein the ALD-type process comprises alternately and sequentially contacting the substrate with vapor phase pulses of a nickel precursor and a second reactant.

22. The method of claim 21, wherein the nickel precursor is selected from the group consisting of nickel betadiketonate compounds, nickel betadiketiminato compounds, nickel aminoalkoxide compounds, nickel amidinate compounds, nickel cyclopentadienyl compounds, nickel carbonyl compounds and combinations thereof.

23. The method of claim 21, wherein the nickel precursor is bis(4-N-ethylamino-3-penten-2-N-ethyliminato)nickel (II)

24. The method of claim 21, wherein the second reactant is an organic reducing agent, hydrogen, or forming gas.

25. The method of claim 19, wherein the nickel thin film is deposited directly on the exposed silicon.

26. The method of claim 19, wherein heating comprises heating the substrate to a temperature greater than about 350°

C.

27. A method for forming a doped nickel silicide layer on a substrate, comprising:

providing a substrate having at least one exposed silicon region;

depositing a nickel film over the silicon region, wherein depositing the nickel film comprises multiple cycles of a primary nickel atomic layer deposition-type process;

depositing a dopant film comprising a second metal over the silicon region, wherein depositing the dopant film comprises one or more cycles of a dopant atomic layer deposition-type process; and

annealing the substrate to form a nickel silicide that is doped with the second metal, wherein the cycles of the primary nickel deposition process and the cycles of the dopant deposition process are carried out at a specific ratio to achieve a desired dopant concentration in the doped metal silicide layer.

28. The method of claim 27 wherein the second metal is platinum.

29. The method of claim 27, wherein depositing the dopant film comprises depositing a dopant oxide by the one or more cycles of the dopant atomic layer deposition-type process and subsequently reducing the dopant oxide to form the dopant film.

30. The method of claim 27, wherein the dopant atomic layer deposition-type process is carried out after the primary nickel atomic layer deposition-type process.

31. The method of claim 27, wherein the primary nickel deposition process comprises alternately and sequentially contacting the substrate with a vapor phase nickel precursor and a second precursor, wherein in each cycle no more than about one monolayer of nickel precursor is formed on the substrate surface and the second reactant reacts with the nickel precursor to form the nickel film.