SELECTIVE DEPOSITION OF ALUMINUM AND NITROGEN CONTAINING MATERIAL

• US 20170040164A1
• Filed: 08/05/2015
• Published: 02/09/2017
• Est. Priority Date: 08/05/2015
• Status: Active Grant

• Current Assignee: ASM IP Holding B.V. (ASM International NV)
• Original Assignee: ASM IP Holding B.V. (ASM International NV)
• Inventors: Wang, Han, Hsieh, Julian, Xie, Qi, Longrie, Delphine, Maes, Jan Willem, de Roest, David, Zhu, Chiyu, Asikainen, Timo
• Granted Patent: US 10,566,185 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: H01L 21/02178 the material containing aluminium, e.g. Al2O3
• CPC Class Codes: H01L 21/02205 the layer being characterised by the precursor material for deposition
• CPC Class Codes: H01L 21/0228 deposition by cyclic CVD, e.g. ALD, ALE, pulsed CVD
• CPC Class Codes: H01L 21/02315 treatment by exposure to a plasma
• CPC Class Codes: H01L 21/283 Deposition of conductive or insulating materials for electrodes conducting electric current
• CPC Class Codes: H01L 21/31111 by chemical means
• CPC Class Codes: H01L 21/31144 using masks
• CPC Class Codes: H01L 21/76834 formation of thin insulating films on the sidewalls or on top of conductors H01L21/76831 takes precedence
• CPC Class Codes: H01L 21/76897 Formation of self-aligned vias or contact plugs, i.e. involving a lithographically uncritical step self-aligned silicidation on field effect transistors H01L29/665

Abstract

Methods are provided for selectively depositing Al and N containing material on a first conductive surface of a substrate relative to a second, dielectric surface of the same substrate. In some aspects, methods of forming an Al and N containing protective layer or etch stop layer for use in integrated circuit fabrication are provided.

Claims

1. A process for selectively depositing a material comprising aluminum and nitrogen on a first surface of a substrate relative to a second surface comprising Si—

O bonds of the same substrate, the process comprising one or more deposition cycles comprising;

contacting the substrate with a first vapor phase precursor comprising aluminum;

contacting the substrate with a second vapor phase precursor comprising nitrogen; and

wherein the material comprising aluminum and nitrogen is deposited on the first surface of the substrate relative to the second Si—

O surface of the same substrate with a selectivity greater than about 50%.

2. The process of claim 1, wherein the first surface comprises at least one of:

copper, titanium nitride, tungsten, and silicon nitride.

3. The process of claim 1, wherein the material comprising aluminum and nitrogen is an aluminum nitride thin film.

4. The process of claim 3, wherein the aluminum nitride thin film comprises oxygen.

5. The process of claim 1, wherein the first vapor phase precursor comprising aluminum is an organometallic aluminum compound.

6. The process of claim 1, wherein the first vapor phase precursor comprising aluminum does not comprise any metals other than aluminum.

7. The process of claim 1, wherein the first vapor phase precursor comprising aluminum has the formula R₃Al, wherein each R can be independently selected from C₁-C₄ alkyl groups.

8. The process of claim 1, wherein the first vapor phase precursor comprising aluminum does not comprise a halide.

9. The process of claim 1, wherein the first vapor phase precursor comprising aluminum comprises one chlorine ligand and at two alkyl ligands.

10. The process of claim 1, wherein the first vapor phase precursor comprising aluminum comprises at least one hydrogen ligand and at least one alkyl ligand.

11. The process of claim 1, wherein the first vapor phase precursor comprising aluminum does not comprise nitrogen, silicon, or oxygen.

12. The process of claim 1, wherein the first vapor phase precursor comprising aluminum comprises tritertbutylaluminum (TTBA), trimethylaluminum (TMA) or triethylaluminum (TEA) and the second vapor phase precursor comprising nitrogen comprises NH₃.

13. The process of claim 1, wherein the second Si—

O surface comprises is a dielectric.

14. The process of claim 1, wherein the second Si—

O surface has a resistivity of more than about 1 ohm·

m.

15. The process of claim 1, wherein the process comprises a thermal atomic layer deposition (ALD) process.

16. The process of claim 1, wherein the process does not comprise plasma in at least 2 consecutive deposition cycles.

17. The process of claim 1, further comprising exposing the substrate to a pretreatment reactant prior to a first deposition cycle.

18. The process of claim 17, wherein the pretreatment reactant comprises plasma.

19. The process of claim 1, further comprising exposing the substrate to plasma after at least one deposition cycle.

20. The process of claim 1, wherein the material comprising aluminum and nitrogen has etch selectivity relative to SiO₂ in dilute HF.

21. The process of claim 1, wherein a ratio of material comprising aluminum and nitrogen deposited on the first surface of the substrate relative to the second Si—

O surface of the same substrate is greater than about 10;

1, and wherein a thickness of material comprising aluminum and nitrogen deposited on first surface of the substrate is greater than about 5 nm.

22. The process of claim 1, wherein a ratio of material comprising aluminum and nitrogen deposited on the first surface of the substrate relative to the second Si—

O surface of the same substrate is greater than about 10;

1 and wherein a thickness of material comprising aluminum and nitrogen deposited on first surface of the substrate is greater than about 1 nm.

23. The process of claim 1, wherein a ratio of material comprising aluminum and nitrogen deposited on the first surface of the substrate relative to the second Si—

O surface of the same substrate is greater than about 10;

1 and wherein the process comprises between about 1 and 25 deposition cycles.

24. The process of claim 1, wherein a ratio of material comprising aluminum and nitrogen deposited on the first surface of the substrate relative to the second Si—

O surface of the same substrate is greater than about 10;

1, and wherein the process comprises between about 1 and 150 deposition cycles.

25. The process of claim 1, wherein less than about 0.1 nm of material comprising aluminum and nitrogen is deposited on the second Si—

O surface of the substrate after between about 1 and 25 deposition cycles.

26. The process of claim 1, wherein a ratio of a wet etch rate of the deposited aluminum and nitrogen containing material to a wet etch rate of SiO₂ is less than about 1:

5.

27. The process of claim 1, wherein the Si—

O surface of the substrate overlies a source/drain region, and further comprising;

removing the second Si—

O surface of the substrate to thereby expose the source/drain region of the substrate; and

forming a contact over the exposed source/drain region of the substrate.

28. A process for selectively depositing a material comprising aluminum and nitrogen on a first surface of a substrate relative to a second dielectric surface of the same substrate, the process comprising one or more deposition cycles comprising:

contacting the substrate with a first vapor phase precursor comprising aluminum;

contacting the substrate with a second vapor phase precursor comprising nitrogen; and

wherein the material comprising aluminum and nitrogen is deposited on the first surface of the substrate relative to the second dielectric surface of the same substrate with a selectivity greater than about 50%.

29. A process for depositing AlN on a substrate, the process comprising at least one deposition cycle comprising:

alternately and sequentially contacting the substrate with vapor phase tritertbutylaluminum (TTBA) and vapor phase NH₃.

30. A process for forming an etch stop layer in a self-aligned contact formation process comprising:

providing a semiconductor substrate comprising a first surface and a second dielectric surface overlying a source/drain region;

removing a portion of the first surface of the substrate to form a recess therein;

selectively depositing a material comprising aluminum and nitrogen on the first surface relative to the second dielectric surface;

removing the second dielectric surface of the substrate to thereby expose the source/drain region of the substrate; and

forming a contact over the exposed source/drain region of the substrate.