SELECTIVE METAL OXIDE DEPOSITION USING A SELF-ASSEMBLED MONOLAYER SURFACE PRETREATMENT

• US 20180076027A1
• Filed: 09/12/2017
• Published: 03/15/2018
• Est. Priority Date: 09/13/2016
• Status: Active Grant

• Current Assignee: Tokyo Electron Limited
• Original Assignee: Tokyo Electron Limited
• Inventors: Tapily, Kandabara N., Leusink, Gerrit J., Wajda, Cory, Kang, Hoyoung
• Granted Patent: US 10,068,764 B2
• Time in Patent Office: Days
• CPC Class Codes: H01L 21/02172 the material containing at least one metal element, e.g. metal oxides, metal nitrides, metal oxynitrides or metal carbides materials containing silicon H01L21/02123; metal silicates H01L21/02142
• CPC Class Codes: H01L 21/02178 the material containing aluminium, e.g. Al2O3
• CPC Class Codes: H01L 21/02181 the material containing hafnium, e.g. HfO2
• CPC Class Codes: H01L 21/02189 the material containing zirconium, e.g. ZrO2
• CPC Class Codes: H01L 21/02205 the layer being characterised by the precursor material for deposition
• CPC Class Codes: H01L 21/02274 in the presence of a plasma [PECVD]
• CPC Class Codes: H01L 21/0228 deposition by cyclic CVD, e.g. ALD, ALE, pulsed CVD
• CPC Class Codes: H01L 21/02304 formation of intermediate layers, e.g. buffer layers, layers to improve adhesion, lattice match or diffusion barriers
• CPC Class Codes: H01L 21/02312 treatment by exposure to a gas or vapour
• CPC Class Codes: H01L 21/3105 After-treatment
• CPC Class Codes: H01L 21/31111 by chemical means
• CPC Class Codes: H01L 21/32 using masks
• CPC Class Codes: H01L 21/321 After treatment
• CPC Class Codes: H01L 21/76801 characterised by the formation and the after-treatment of the dielectrics, e.g. smoothing
• CPC Class Codes: H01L 21/76826 by contacting the layer with gases, liquids or plasmas
• CPC Class Codes: H01L 21/76829 characterised by the formation of thin functional dielectric layers, e.g. dielectric etch-stop, barrier, capping or liner layers
• CPC Class Codes: H01L 21/76883 Post-treatment or after-treatment of the conductive material

Abstract

Embodiments of the invention provide methods for selective film deposition using a surface pretreatment. According to one embodiment, the method includes providing a substrate containing a dielectric layer and a metal layer, exposing the substrate to a reactant gas containing a molecule that forms self-assembled monolayers (SAMs) on the substrate, and thereafter, selectively depositing a metal oxide film on a surface of the dielectric layer relative to a surface of the metal layer by exposing the substrate to a deposition gas.

Claims

1. A method of processing a substrate, comprising:

providing a substrate containing a dielectric layer and a metal layer;

exposing the substrate to a reactant gas containing a molecule that forms self-assembled monolayers (SAMs) on the substrate; and

thereafter, selectively depositing a metal oxide film on a surface of the dielectric layer relative to a surface of the metal layer by exposing the substrate to a deposition gas.

2. The method of claim 1, wherein the metal layer contains Cu, Al, Ta, Ti, W, Ru, Co, Ni, or Mo.

3. The method of claim 1, further comprising oxidizing the surface of the metal layer prior to or during the exposing of the substrate to the reactant gas.

4. The method of claim 1, wherein the molecule includes a head group, a tail group, and a functional end group, and wherein the head group includes a thiol, a silane, or a phosphonate.

5. The method of claim 1, wherein the molecule includes perfluorodecyltrichlorosilane (CF₃(CF₂)₇CH₂CH₂SiCl₃), perfluorodecanethiol (CF₃(CF₂)₇CH₂CH₂SH), chlorodecyldimethylsilane (CH₃(CH₂)₈CH₂Si(CH₃)₂Cl), or tertbutyl(chloro)dimethylsilane ((CH₃)₃CSi(Cl)(CH₃)₂)).

6. The method of claim 1, wherein the metal oxide film contains HfO₂, ZrO₂, or Al₂O₃.

7. The method of claim 1, wherein a density of the SAMs is greater on the surface of the metal layer than on the surface of the dielectric layer.

8. The method of claim 1, wherein the exposing the substrate to the deposition gas forms metal oxide nuclei on the surface of the metal layer, the method further comprising

removing, by etching, the metal oxide nuclei from the surface of the metal layer.

9. The method of claim 1, further comprising:

in the absence of any oxidizing and hydrolyzing agent, at a substrate temperature of approximately 150°

C., or less, exposing the substrate to a process gas containing a silanol gas to selectively deposit a conformal SiO₂ film on the metal oxide film relative to the metal layer.

10. The method of claim 9, wherein the silanol gas is selected from the group consisting of tris(tert-pentoxy) silanol, tris(tert-butoxy) silanol, and bis(tert-butoxy)(isopropoxy) silanol.

11. A method of processing a substrate, comprising:

providing a substrate containing a dielectric layer and a metal layer;

exposing the substrate to a reactant gas containing a molecule that forms self-assembled monolayers (SAMs) on the substrate;

thereafter, selectively forming a metal-containing catalyst layer on a surface of the dielectric layer relative to a surface of the metal layer by exposing the substrate to a gas containing a metal-containing precursor; and

in the absence of any oxidizing and hydrolyzing agent, at a substrate temperature of approximately 150°

C., or less, exposing the substrate to a process gas containing a silanol gas to selectively deposit a SiO₂ film on the metal-containing catalyst layer relative to the metal layer.

12. The method of claim 11, wherein the metal layer contains Cu, Al, Ta, Ti, W, Ru, Co, Ni, or Mo.

13. The method of claim 11, further comprising oxidizing the surface of the metal layer prior to or during the exposing of the substrate to the reactant gas.

14. The method of claim 11, wherein the molecule includes a head group, a tail group, and a functional end group, wherein the head group includes a thiol, a silane, or a phosphonate.

15. The method of claim 11, wherein the molecule includes perfluorodecyltrichlorosilane (CF₃(CF₂)₇CH₂CH₂SiCl₃), perfluorodecanethiol (CF₃(CF₂)₇CH₂CH₂SH), chlorodecyldimethylsilane (CH₃(CH₂)₈CH₂Si(CH₃)₂Cl), or tertbutyl(chloro)dimethylsilane ((CH₃)₃CSi(Cl)(CH₃)₂)).

16. The method of claim 11, wherein the metal-containing precursor includes aluminum (Al) or titanium (Ti).

17. The method of claim 11, wherein the metal-containing precursor includes AlMe₃.

18. The method of claim 11, wherein a density of the SAMs is greater on the surface of the metal layer than on the surface of the dielectric layer.

19. The method of claim 11, wherein the exposing the substrate to the gas containing the metal-containing precursor forms metal-containing nuclei on the surface of the metal layer, the method further comprising

removing, by etching, the metal-containing nuclei from the surface of the metal layer.

20. The method of claim 11, wherein the silanol gas is selected from the group consisting of tris(tert-pentoxy) silanol, tris(tert-butoxy) silanol, and bis(tert-butoxy)(isopropoxy) silanol.