DEPOSITION OF RUTHENIUM OR RUTHENIUM DIOXIDE

• US 20110027977A1
• Filed: 07/02/2010
• Published: 02/03/2011
• Est. Priority Date: 07/31/2009
• Status: Active Grant

• Current Assignee: ASM IP Holding B.V. (ASM International NV)
• Original Assignee: ASM America Incorporated (ASM International NV)
• Inventors: Li, Dong
• Granted Patent: US 8,329,569 B2
• Time in Patent Office: Days
• US Class Current: 438/584
• CPC Class Codes: C23C 16/0281 of metallic sub-layers C23C16/029 takes precedence
• CPC Class Codes: C23C 16/06 characterised by the deposition of metallic material
• CPC Class Codes: C23C 16/45527 characterized by the ALD cycle, e.g. different flows or temperatures during half-reactions, unusual pulsing sequence, use of precursor mixtures or auxiliary reactants or activations
• 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 21/76846 Layer combinations

Abstract

Methods of forming ruthenium or ruthenium dioxide are provided. The methods may include using ruthenium tetraoxide (RuO₄) as a ruthenium precursor. In some embodiments for forming ruthenium, methods include forming a seed layer, and forming a ruthenium layer on the seed layer, using RuO₄. In other embodiments, methods include performing atomic layer deposition cycles, which include using RuO₄ and another ruthenium-containing co-precursor. In yet other embodiments, methods include adsorbing a reducing agent over a substrate, and supplying RuO₄ to be reduced to ruthenium by the adsorbed reducing agent. In other embodiments for forming ruthenium dioxide, methods may include providing an initial seed layer formed of, for example, an organic compound, and supplying RuO₄ over the seed layer.

Claims

1. A method of depositing a ruthenium layer over a substrate, the method comprising:

supplying triruthenium dodecacarbonyl over a surface of a substrate to form a seed layer over the surface of the substrate; and

conducting deposition over the seed layer, wherein the deposition comprises;

supplying ruthenium tetraoxide over the seed layer.

2. The method of claim 1, wherein the deposition further comprises supplying a reducing agent over the seed layer.

3. The method of claim 2, wherein the reducing agent comprises at least one selected from the group consisting of NH₃, H₂, and N₂H₄.

4. The method of claim 2, wherein the deposition comprises supplying the ruthenium tetraoxide over the seed layer simultaneously with supplying the reducing agent.

5. The method of claim 2, wherein the deposition comprises conducting at least one deposition cycle, which comprises:

supplying the ruthenium tetraoxide over the seed layer without supplying a reducing agent during a first time period; and

supplying the reducing agent over the seed layer without supplying ruthenium tetraoxide during a second time period after the first time period.

6. The method of claim 5, wherein the at least one deposition cycle further comprises supplying a purge gas over the seed layer between the first and second time periods.

7. The method of claim 5, wherein the at least one deposition cycle further comprises supplying a purge gas over the seed layer after the second time period.

8. A method for forming a ruthenium thin film on a substrate, the method comprising:

loading a substrate into a reactor; and

conducting a plurality of deposition cycles on the substrate, at least one of the cycles comprising;

supplying triruthenium dodecacarbonyl to the reactor during a first time period; and

supplying ruthenium tetraoxide to the reactor during a second time period between the first time period and an immediately subsequent deposition cycle.

9. The method of claim 8, wherein the at least one of the cycles further comprises supplying a purge gas to the reactor between the first time period and the second time period.

10. The method of claim 8, wherein the at least one of the cycles further comprises supplying a purge gas to the reactor between the second time period and the immediately subsequent deposition cycle.

11. The method of claim 8, further comprising supplying hydrogen gas to the reactor after conducting the plurality of deposition cycles.

12. The method of claim 11, further comprising supplying a purge gas to the reactor after supplying the hydrogen gas.

13. The method of claim 8, wherein the at least one of the cycles further comprises supplying hydrogen gas to the reactor during a third time period between the second time period and the immediately subsequent deposition cycle.

14. The method of claim 13, wherein the at least one of the cycles further comprise supplying a purge gas to the reactor between the third time period and the immediately subsequent deposition cycle.

15. A method for forming a ruthenium thin film on a substrate, the method comprising:

loading a substrate including a surface into a reactor;

supplying a reducing agent to the reactor during a first time period such that at least a portion of the reducing agent is adsorbed on the surface of the substrate;

supplying ruthenium tetraoxide to the reactor during a second time period after the first time period; and

supplying a reducing agent to the reactor during a third time period after the second time period.

16. The method of claim 15, further comprising supplying a purge gas to the reactor between the first and second time periods.

17. The method of claim 15, further comprising supplying a purge gas to the reactor after the third time period.

18. The method of claim 15, further comprising supplying a reducing agent to the reactor simultaneously with supplying the ruthenium tetraoxide to the reactor during the second time period.

19. The method of claim 15, wherein supplying the ruthenium tetraoxide to the reactor during the second time period comprises supplying the ruthenium tetraoxide to the reactor without supplying a reducing agent to the reactor.

20. The method of claim 19, further comprising supplying a purge gas to the reactor between the second and third time periods.

21. The method of claim 15, further comprising conducting at least one deposition cycle between the second and third time periods, wherein the at least one deposition cycle comprises:

supplying a reducing agent to the reactor without supplying ruthenium tetraoxide during a fourth time period; and

supplying ruthenium tetraoxide to the reactor without supplying a reducing agent during a fifth time period.

22. The method of claim 21, wherein the fourth time period has substantially the same duration as the first time period, and wherein the fifth time period has substantially the same duration as the second time period.

23. The method of claim 21, wherein the reducing agent supplied during the fourth time period comprises at least one selected from the group consisting of NH₃, H₂, and N₂H₄.

24. The method of claim 15, wherein the reducing agent supplied during the first or third time period comprises at least one selected from the group consisting of NH₃, H₂, and N₂H₄.

25. A method for forming a ruthenium dioxide thin film on a substrate, the method comprising:

loading a substrate including a surface into a reactor;

supplying an organic compound to the reactor during a first time period such that a layer of the organic compound is formed on the surface of the substrate; and

supplying ruthenium tetraoxide to the reactor during a second time period after the first time period.

26. The method of claim 25, further comprising supplying a purge gas to the reactor between the first and second time periods.

27. The method of claim 25, further comprising supplying ruthenium tetraoxide and a non-reducing gas to the reactor during a third time period after the second time period.

28. The method of claim 27, further comprising supplying a purge gas to the reactor between the second and third time periods.

29. The method of claim 27, further comprising supplying a purge gas to the reactor after the third time period.

30. The method of claim 27, further comprising conducting at least one deposition cycle after the third time period, wherein the at least one deposition cycle comprises:

supplying ruthenium tetraoxide and a non-reducing gas to the reactor during a fourth time period; and

supplying a purge gas to the reactor during a fifth time period after the fourth time period.

31. The method of claim 30, wherein the fourth time period has substantially the same duration as the third time period.

32. The method of claim 27, wherein the non-reducing gas comprises at least one selected from the group consisting of N₂, O₂, and Ar.

33. The method of claim 25, wherein the organic compound comprises at least one selected from the group consisting of alkane, alkene, and alkyne compounds, and derivatives of the foregoing.