SELECTIVE FORMATION OF METALLIC FILMS ON METALLIC SURFACES

• US 20170069527A1
• Filed: 11/18/2016
• Published: 03/09/2017
• 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
• Granted Patent: US 10,157,786 B2
• Time in Patent Office: Days
• 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;

after cleaning carrying out one or more deposition cycles, each cycle comprising;

contacting the substrate with a first precursor comprising silicon or boron to selectively form a layer of first material comprising Si or B on the first metal surface relative to the second dielectric surface; and

converting the first material on the first metal surface to a second metallic material by exposing the first material to a second precursor comprising metal,

wherein the selectivity for deposition on the first surface relative to the second surface is greater than about 50%.

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

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

4. The method of claim 1, wherein the second metallic material comprises a metal nitride.

5. The method of claim 1, wherein the second metallic material comprises a transition metal.

6. The method of claim 5, wherein the second metallic material comprises tungsten.

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

8. The method of claim 7, wherein the plasma comprises one or more of H, N and Ar.

9. The method of claim 1, wherein the metallic material comprises a metal silicide.

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

11. The method of claim 1, wherein the dielectric comprises a low k material with a dielectric value of less than about 4.0.

12. The method of claim 1, wherein the second precursor comprises WF₆

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

14. The method of claim 1, further comprising repeating the contacting and converting steps two or more times.

15. The method of claim 1, wherein the second metallic material has a thickness less than about 10 nm.

16. The method of claim 1, wherein the second metallic material has a thickness of less than about 3 nm.

17. The method of claim 1, wherein the temperature of the substrate during the one or more deposition cycles is less than about 150°

C.