Methods for wet metal seed deposition for bottom up gapfill of features

Patent metadata

Field	Value
Publication number	US-10103056-B2
Application number	US-201715453098-A
Country	US
Kind code	B2
Filing date	Mar 8, 2017
Priority date	Mar 8, 2017
Publication date	Oct 16, 2018
Grant date	Oct 16, 2018

Abstract

A method of depositing a metal seed for performing bottom-up gapfill of features of a substrate includes providing a substrate including a plurality of features; flowing a dilute metal precursor solution into the features, wherein the dilute metal precursor solution includes a metal precursor and a dilution liquid; evaporating the dilution liquid to locate the metal precursor at bottoms of the plurality of features; exposing the substrate to a plasma treatment to reduce the metal precursor to at least one of a metal or a metal alloy and to form a seed layer; performing a heat treatment on the substrate; and using a selective gapfill process to fill the features with a transition metal in contact with the seed layer.

First claim

What is claimed is:

1. A method of depositing a metal seed for performing bottom-up gapfill of features of a substrate, comprising:
providing a substrate including a plurality of features;
flowing a dilute metal precursor solution into the features, wherein the dilute metal precursor solution includes a metal precursor and a dilution liquid;
evaporating the dilution liquid to locate the metal precursor at bottoms of the plurality of features,
wherein evaporating the dilution liquid includes exposing the substrate to a gradient dry process;
exposing the substrate to a plasma treatment to reduce the metal precursor to at least one of a metal or a metal alloy and to form a seed layer only at the bottoms of the plurality of features;
performing a heat treatment on the substrate; and
using a selective gapfill process to fill the features with a transition metal in contact with the seed layer and not other exposed portions of the plurality of features.

2. The method of claim 1 , wherein the substrate includes a liner layer and the dilute metal precursor solution is applied to the liner layer.

3. The method of claim 1 , wherein the transition metal is selected from a group consisting of nickel (Ni), cobalt (Co), copper (Cu), molybdenum (Mo), ruthenium (Ru), iridium (Ir), platinum (Pt), palladium (Pd) and tungsten (W).

4. The method of claim 1 , wherein the selective gapfill process includes electroless deposition.

5. The method of claim 1 , wherein the dilution liquid comprises at least one of a carrier liquid and a solvent.

6. The method of claim 1 , wherein the dilution liquid is water-free.

7. The method of claim 1 , wherein the dilution liquid comprises a liquid selected from a group consisting of alcohol, ether, ester, perflouro-ether.

8. The method of claim 1 , wherein the dilution liquid comprises a liquid selected from a group consisting isopropyl alcohol (IPA) and ethyl alcohol (EtOH).

9. The method of claim 1 , wherein the dilute metal precursor solution is at least one of deposited or condensed in the plurality of features using by capillary action.

10. A method of depositing a metal seed for performing bottom-up gapfill of features of a substrate, comprising:
providing a substrate including a plurality of features;
flowing a dilute metal precursor solution into the features, wherein the dilute metal precursor solution includes a metal precursor and a dilution liquid;
evaporating the dilution liquid to locate the metal precursor at bottoms of the plurality of features;
exposing the substrate to a plasma treatment to reduce the metal precursor to at least one of a metal or a metal alloy and to form a seed layer;
performing a heat treatment on the substrate; and
using a selective gapfill process to fill the features with a transition metal in contact with the seed layer,
wherein evaporating the dilution liquid includes exposing the substrate to a gradient dry process.

11. The method of claim 10 , wherein the features have openings having a width that is less than or equal to 10 nm.

12. The method of claim 10 , wherein the features have openings having a width in a range from 7 to 9 nm.

13. The method of claim 10 , wherein the features have openings having a width in a range from 4 to 7 nm.

14. The method of claim 10 , wherein the seed layer has a thickness in a range from 2-4 nm.

15. The method of claim 10 , wherein the heat treatment comprises annealing at a temperature in a range from 200° C. to 400° C.

16. The method of claim 10 , wherein the heat treatment comprises annealing at a temperature in a range from 250° C. to 350° C.

17. The method of claim 10 , wherein the transition metal is selected from a group consisting of nickel (Ni), cobalt (Co), copper (Cu), molybdenum (Mo), ruthenium (Ru), iridium (Ir), platinum (Pt), palladium (Pd) and tungsten (W).

18. The method of claim 10 , wherein the selective gapfill process includes electroless deposition.

19. The method of claim 10 , wherein the dilution liquid comprises at least one of a carrier liquid and a solvent.

20. The method of claim 10 , wherein the dilution liquid is water-free.

21. The method of claim 10 , wherein the dilution liquid comprises a liquid selected from a group consisting of alcohol, ether, ester, perflouro-ether.

22. The method of claim 10 , wherein the dilution liquid comprises a liquid selected from a group consisting isopropyl alcohol (IPA) and ethyl alcohol (EtOH).

23. The method of claim 10 , wherein the dilute metal precursor solution is at least one of deposited or condensed in the plurality of features using by capillary action.

24. The method of claim 10 , wherein the substrate includes a liner layer and the dilute metal precursor solution is applied to the liner layer.

25. The method of claim 24 , wherein the liner layer is made of a material selected from a group consisting of titanium nitride (TiN), tungsten carbonitride (WCN), and tantalum nitride (TaN).

26. The method of claim 24 , wherein the liner layer is made of a material selected from a group consisting of silicon dioxide, a metal, or a dielectric.

27. The method of claim 24 , wherein the at least one of the metal or the metal alloy is selected to catalytically react with the transition metal but not the liner layer.

Assignees

• Lam Res Corp

Inventors

• Tan Samantha
• Volosskiy Boris
• Kim Taeseung
• Nalla Praveen
• Tjokro Novy
• Kolics Artur

Classifications

• H10W20/4437

  the principal metal being a transition metal · CPC title

• H10P14/46

  using a liquid · CPC title

• H10W20/0526

  by thermal treatment thereof · CPC title

• H10W20/057

  by selectively depositing, e.g. by using selective CVD or plating · CPC title

• H10W20/055

  by formation methods other than physical vapour deposition [PVD], chemical vapour deposition [CVD] or liquid deposition · CPC title