Multi-layer feature fill

Patent metadata

Field	Value
Publication number	US-12014928-B2
Application number	US-201917250503-A
Country	US
Kind code	B2
Filing date	Jul 31, 2019
Priority date	Jul 31, 2018
Publication date	Jun 18, 2024
Grant date	Jun 18, 2024

Abstract

Described herein are methods and apparatuses for filling semiconductor substrate structures with conductive material. The methods involve depositing multi-layer bulk metal films in structures with one or more deposition conditions changed when transitioning from layer-to-layer. The methods result in high fill quality, high throughput, low precursor consumption, and low roughness. Multi-station chambers to perform the methods are also provided.

First claim

The invention claimed is:

1. A method of filling a 3-D structure of a partially manufactured semiconductor substrate with a conductive material, the 3-D structure comprising sidewalls, a plurality of openings in the sidewalls leading to a plurality of features having a plurality of interior regions fluidically accessible through the openings, the method comprising:
depositing a first bulk layer of the conductive material within the 3-D structure such that the first bulk layer partially fills the plurality of interior regions of the 3-D structure;
depositing a second bulk layer of the conductive material within the 3-D structure on the first bulk layer such that the second bulk layer at least partially fills the plurality of interior regions of the 3-D structure; and
depositing a third bulk layer of the conductive material within the 3-D structure on the sidewalls, wherein the first bulk layer, second bulk layer, and third bulk layer are deposited at different conditions.

2. The method of claim 1 , wherein the conductive material is tungsten.

3. The method of claim 1 , wherein the first and second bulk layers are deposited by atomic layer deposition (ALD) processes.

4. The method of claim 3 , wherein the third bulk layer is deposited by an ALD process.

5. The method of claim 3 , wherein the third bulk layer is deposited by a chemical vapor deposition (CVD) process.

6. The method of claim 3 , wherein each of the ALD processes comprises sequential pulses of a metal-containing precursor and a reducing agent.

7. The method of claim 6 , wherein one or more of the flow rate and the pulse time of the metal-containing precursor pulse is greater during deposition of the first bulk layer than during depositions of the second bulk layer and the third bulk layer.

8. The method of claim 1 , further comprising depositing a fourth bulk layer of the conductive material on the third bulk layer.

9. The method of claim 1 , wherein the conductive material is molybdenum, ruthenium, or cobalt.

10. The method of claim 1 , further comprising exposing the substrate to a nitrogen (N 2 ) soak in between deposition of two of the bulk layers.

11. A method comprising:
providing a substrate to a multi-station deposition chamber;
depositing in a first station of the multi-station deposition chamber a first metal bulk layer on the substrate at a first set of conditions; transferring the substrate to a second station of the multi- station deposition chamber and depositing a second metal bulk layer on the first metal bulk layer at a second set of conditions; transferring the substrate to a third station of the multi-station deposition chamber and depositing a third metal bulk layer on the second metal bulk layer at a third set of conditions, wherein transitioning from the first set of conditions to the second set of conditions comprises one or more of: changing a metal precursor pulse time, changing a metal precursor flowrate, and changing a pedestal temperature, and transitioning from the second set of conditions to the third set of conditions comprises one or more of: changing a metal-containing precursor pulse time, changing a metal-containing precursor flowrate, and changing a pedestal temperature.

12. The method of claim 11 , wherein the metal of the metal bulk layers is one of tungsten, molybdenum, cobalt, and ruthenium.

13. The method of claim 11 , wherein transitioning from the first set of conditions to the second set of conditions comprises increasing a metal precursor flowrate or increasing a metal-containing precursor pulse time.

14. The method of claim 11 , wherein transitioning from the first set of conditions to the second set of conditions comprises increasing a purge time.

15. The method of claim 11 , wherein transitioning from the first set of conditions to the second set of conditions comprises decreasing a metal precursor flowrate or decreasing a metal-containing precursor pulse time.

16. The method of claim 11 , wherein the substrate comprises a feature and the first metal bulk layer, the second metal bulk layer, and the third metal bulk layer together fill the feature.

17. A multi-station chamber comprising:
a first station comprising a first showerhead and a first pedestal;
a second station comprising a second showerhead and a second pedestal;
a third station comprising a third showerhead and a third pedestal; and a controller comprising machine-readable instructions to:
deposit in the first station of the multi-station chamber a first metal bulk layer on a substrate at a first set of conditions; transfer the substrate to the second station of the multi-station chamber and deposit a second metal bulk layer on the first metal bulk layer at a second set of conditions; transfer the substrate to the third station of the multi-station chamber and deposit a third metal bulk layer on the second metal bulk layer at a third set of conditions, wherein transitioning from the first set of conditions to the second set of conditions comprises one or more of: changing a metal precursor pulse time, changing a metal precursor flowrate, and changing a pedestal temperature, and transitioning from the second set of conditions to the third set of conditions comprises one or more of: changing a metal-containing precursor pulse time, changing a metal-containing precursor flowrate, and changing a pedestal temperature.

Assignees

• Lam Res Corp

Inventors

• Ba Xiaolan
• Deng Ruopeng
• Gao Juwen
• Gopinath Sanjay
• Schloss Lawrence

Classifications

• H10W20/4441

  the principal metal being a refractory metal · CPC title

• H10W20/4432

  the principal metal being a noble metal, e.g. gold · CPC title

• H10W20/4403

  based on metals, e.g. alloys, metal silicides (H10W20/4484 takes precedence) · CPC title

• H10W20/0698

  Local interconnections · CPC title

• H10W20/083

  the openings being via holes penetrating underlying conductors · CPC title