Selective formation of metallic films on metallic surfaces

• US 9,502,289 B2
• Filed: 06/11/2015
• Issued: 11/22/2016
• Est. Priority Date: 12/09/2011
• Status: Active Grant

• Current Assignee: ASM International NV
• Original Assignee: ASM International NV
• Inventors: Haukka, Suvi P., Niskanen, Antti, Tuominen, Marko
• Primary Examiner(s): Mandala, Michelle
• Assistant Examiner(s): Vuong, Thai T
• Application Number:
  US14/737,293
• Publication Number:
  US 20160005649A1
• Time in Patent Office: 530 Days
• Field of Search: 438/653, 438/778, 438/763, 257/632
• US Class Current: 1/1
• CPC Class Codes: C23C 16/04 Coating on selected surface areas, e.g. using masks
• CPC Class Codes: C23C 16/14 Deposition of only one other metal element
• CPC Class Codes: C23C 16/45536 Use of plasma, radiation or electromagnetic fields
• CPC Class Codes: C23C 16/45553 characterized by the use of precursors specially adapted for ALD
• CPC Class Codes: H01L 21/02068 during, before or after processing of conductive layers, e.g. polysilicon or amorphous silicon layers
• CPC Class Codes: H01L 21/28518 the conductive layers comprising silicides H01L21/28537 takes precedence
• 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 21/3105 After-treatment
• CPC Class Codes: H01L 21/76826 by contacting the layer with gases, liquids or plasmas
• CPC Class Codes: H01L 21/76849 the layer being positioned on top of the main fill metal
• CPC Class Codes: H01L 21/7685 the layer covering a conductive structure H01L21/76849 takes precedence
• CPC Class Codes: H01L 21/76864 Thermal treatment
• CPC Class Codes: H01L 21/76867 characterized by methods of formation other than PVD, CVD or deposition from a liquids PVD H01L21/2855; CVD H01L21/28556; deposition from liquids H01L21/288
• CPC Class Codes: H01L 21/76883 Post-treatment or after-treatment of the conductive material
• 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 21/76889 by forming silicides of refractory metals
• CPC Class Codes: H01L 23/53238 Additional layers associated with copper layers, e.g. adhesion, barrier, cladding layers

Abstract

Metallic layers can be selectively deposited on one surface of a substrate relative to a second surface of the substrate. In some embodiments, the metallic layers are selectively deposited on copper instead of insulating or dielectric materials. In some embodiments, a first precursor forms a layer on the first surface and is subsequently reacted or converted to form a metallic layer. The deposition temperature may be selected such that a selectivity of above about 50% or even about 90% is achieved.

Claims

1. A method for selectively depositing a film on a substrate comprising a first metal surface and a second dielectric surface, the method comprising:

cleaning the substrate;

forming a surface termination on the second dielectric surface;

after cleaning carrying out one or more deposition cycles at a temperature of less than 150°

C., each cycle comprising;

contacting the substrate with a first precursor; and

contacting the substrate with a second precursor comprising a metal,

wherein deposition on the first metal surface relative to the second dielectric surface has a selectivity of greater than about 50%.

2. The method of claim 1, wherein the one or more deposition cycles are carried out prior to forming the surface termination on the second dielectric surface.

3. The method of claim 1, wherein the one or more deposition cycles are carried out after forming the surface termination on the second dielectric surface.

4. The method of claim 3, wherein the cleaning is carried out after forming the surface termination on the second dielectric surface.

5. The method of claim 1, wherein the surface termination is formed in a first reaction chamber and the one or more deposition cycles are carried out in a second, different reaction chamber.

6. The method of claim 1, wherein the first precursor comprises Si or B.

7. The method of claim 1, wherein the second precursor comprises a metal selected from W, Ta, Nb, Ti, Mo and V.

8. The method of claim 7, wherein the second precursor comprises WF₆.

9. The method of claim 1, wherein cleaning comprises removing a passivation layer from the first metal surface.

10. The method of claim 1, wherein cleaning comprises exposing the substrate to a plasma.

11. The method of claim 1, wherein forming the surface termination comprises silylation of the second dielectric surface.

12. The method of claim 1, wherein forming the surface termination comprises forming —

Si(CH₃)₃ groups on the second dielectric surface.

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

14. The method of claim 1, wherein the film comprises a metal nitride or metal silicide.

15. The method of claim 1, additionally comprising annealing the substrate after cleaning and prior to carrying out the one or more deposition cycles.

16. The method of claim 1, wherein the method has a selectivity for depositing material on the first metal surface relative to the second dielectric surface of above about 90%.

17. A method for selectively depositing a film on a first metal surface of a substrate relative to a second dielectric surface of the substrate, the method comprising:

conducting a dielectric restoration step;

carrying out one or more deposition cycles at a temperature of less than 150°

C., each cycle comprising alternately and sequentially contacting the substrate with a first precursor and a second precursor comprising a metal selected from W, Ta, Nb, Ti, Mo and V,

wherein deposition on the first metal surface relative to the second dielectric surface is greater than about 50% selective.

18. The method of claim 17, wherein the dielectric restoration step and the deposition cycles are conducted in different reaction spaces.

19. The method of claim 17, wherein the dielectric restoration step comprises contacting the second dielectric surface with SiHxLy, where L is selected from alkyl, alkenyl, alkynyl, alkoxide and amide groups.

20. The method of claim 17, wherein the dielectric restoration step comprises silylation of the second dielectric surface.

21. The method of claim 17, wherein the dielectric restoration step comprises forming —

Si(CH₃)₃ groups on the second dielectric surface.

22. The method of claim 17, wherein the dielectric restoration step is conducted prior to conducting the one or more deposition cycles.

23. The method of claim 17, wherein the selectivity is greater than about 90%.

24. The method of claim 17, additionally comprising annealing the substrate at a temperature from 150°

C. to 400°

C. prior to conducting the deposition cycles.

25. The method of claim 17, wherein an organic layer is formed on the dielectric surface prior to carrying out the one or more deposition cycles.

26. The method of claim 25, wherein the organic layer makes the dielectric layer more resistant to metal fluorides.

27. The method of claim 17, wherein the film is a metal nitride or metal silicide.

28. A method for selectively depositing a film on a substrate comprising a first metal surface and a second dielectric surface, the method comprising:

cleaning the substrate;

forming a surface termination on the second dielectric surface;

after cleaning carrying out one or more deposition cycles at a temperature of less than 150°

C., each cycle comprising;

exposing the substrate to a first precursor; and

exposing the substrate to a second precursor comprising a metal,

wherein a thin film is selectively deposited on the first metal surface relative to the second dielectric surface and the selectivity is greater than about 50%.

29. The method of claim 28, wherein the one or more cycles are carried out prior to forming a surface termination on the second dielectric surface.

30. The method of claim 28, wherein the second precursor comprises a metal selected from W, Ta, Nb, Ti, Mo and V.

31. The method of claim 28, wherein forming a surface termination comprises forming —

Si(CH₃)₃ groups on the second dielectric surface.