Low resistance contacts including intermetallic alloy of nickel, platinum, titanium, aluminum and type IV semiconductor elements

Patent metadata

Field	Value
Publication number	US-10985105-B2
Application number	US-201816168092-A
Country	US
Kind code	B2
Filing date	Oct 23, 2018
Priority date	Sep 6, 2016
Publication date	Apr 20, 2021
Grant date	Apr 20, 2021

Abstract

A method of forming a contact to a semiconductor device is provided that forms an alloy composed of nickel (Ni), platinum (Pt), aluminum (Al), titanium (Ti) and a semiconductor material. The methods may include forming a nickel and platinum semiconductor alloy at a base of a via. A titanium layer having an angstrom scale thickness is deposited in the via in contact with the nickel platinum semiconductor alloy. An aluminum containing fill is deposited atop the titanium layer. A forming gas anneal including an oxygen containing atmosphere is applied to the structure to provide a contact alloy comprising nickel, platinum, aluminum, titanium and a semiconductor element from the contact surface of the semiconductor device.

First claim

What is claimed is:

1. A method of forming a contact to a semiconductor device comprising:
forming a nickel platinum semiconductor alloy with a first anneal at a base of a via opening on a silicon contact surface to the semiconductor device, wherein the nickel platinum semiconductor alloy is formed with a single stage thermal anneal;
depositing a titanium layer having an angstrom scale thickness in contact with the nickel platinum semiconductor alloy in the via opening;
forming an aluminum containing fill on the titanium layer in a lower portion of the via opening;
forming a metal nitride layer and metal containing contact to substantially fill the via opening and completing a material stack beginning with the nickel platinum semiconductor alloy; and
applying a second anneal after at least said depositing the titanium layer to the material stack to provide a contact alloy comprising nickel, platinum, aluminum, titanium and a semiconductor element from the contact surface of the semiconductor device, the contact alloy comprising nickel (Ni) ranging from 20 at. % to 30 at. %, platinum (Pt) ranging from 0 at. % to 10 at. %, aluminum (Al) ranging from 40 at. % to 60 at. %, and silicon (Si) ranging from 5 at. % to 20 at. %.

2. The method of claim 1 , wherein the contact alloy is (Al x Si 1-x ) 7 Ni 3 .

3. The method of claim 1 , wherein the titanium layer is deposited using e-beam physical vapor deposition, wherein the titanium layer has a thickness of 100 Å or less.

4. The method of claim 1 , wherein the metal nitride layer is a metal nitride selected from the group consisting of TiN, TaN, WN, AlTaN and combinations thereof.

5. The method of claim 1 , wherein the metal containing contact comprises W, Al, Cu, Ti, Ta or a combination thereof.

6. The method of claim 1 , wherein the contact alloy comprising nickel, platinum, aluminum, titanium and the semiconductor element comprises a Ni(Pt)—Ti—Al alloy with Si or SiGe.

7. A method of forming a contact to a semiconductor device comprising:
forming a nickel platinum semiconductor alloy with a first anneal on a contact surface to the semiconductor device comprised of silicon germanium, wherein the nickel platinum semiconductor alloy is formed with a single stage thermal anneal;
depositing a titanium layer having an angstrom scale thickness in contact with the nickel platinum semiconductor alloy;
forming an aluminum containing fill on the titanium layer;
forming a metal nitride layer and metal containing contact completing a material stack beginning with the nickel platinum semiconductor alloy; and
applying a second anneal after at least said depositing the titanium layer to the material stack to provide a contact alloy comprising nickel, platinum, aluminum, titanium and a semiconductor element from the contact surface of the semiconductor device, the contact alloy comprising nickel (Ni) ranging from 20 at. % to 30 at. %, platinum (Pt) ranging from 0 at. % to 10 at. %, aluminum (Al) ranging from 40 at. % to 60 at. %, silicon (Si) ranging from 5 at. % to 20 at. % and germanium (Ge) ranging from 0 at. % to 15 at. %.

8. The method of claim 7 , wherein the titanium layer is deposited using e-beam physical vapor deposition.

9. The method of claim 7 , wherein the titanium layer has a thickness of 100 Å or less.

10. The method of claim 7 , wherein the metal nitride layer is a metal nitride selected from the group consisting of TiN, TaN, WN, AlTaN and combinations thereof.

11. The method of claim 7 , wherein the metal containing contact comprises W, Al, Cu, Ti, Ta or a combination thereof.

12. The method of claim 7 , wherein the contact alloy comprising nickel, platinum, aluminum, titanium comprises a Ni(Pt)—Ti—Al alloy.

13. The method of claim 12 , wherein the semiconductor element from the contact surface of the semiconductor device in the contact alloy includes Si or SiGe.

14. A method of forming a contact to a semiconductor device comprising:
forming Ni(Pt)—Ti—Al alloy with Si or SiGe on a contact surface to the semiconductor device with a first anneal;
depositing a titanium layer having an angstrom scale thickness in contact with the nickel platinum semiconductor alloy;
forming an aluminum containing fill on the titanium layer;
forming a metal nitride layer and metal containing contact completing a material stack beginning with the nickel platinum semiconductor alloy; and
applying a second anneal after at least said depositing the titanium layer to the material stack to provide a contact alloy including a semiconductor element from the contact surface of the semiconductor device, wherein the contact alloy is (Al x Si 1-x ) 7 Ni 3 .

15. The method of claim 14 , wherein the titanium layer is deposited using e-beam physical vapor deposition.

16. The method of claim 14 , wherein the titanium layer has a thickness of 100 Å or less.

17. The method of claim 14 , wherein the metal nitride layer is a metal nitride selected from the group consisting of TiN, TaN, WN, AlTaN and combinations thereof.

18. The method of claim 14 , wherein the metal containing contact comprises W, Al, Cu, Ti, Ta or a combination thereof.

Assignees

• IBM

Inventors

• Bruley John
• Chu Jack O
• Lee Kam-Leung
• Ozcan Ahmet S
• Solomon Paul M
• Yau Jeng-Bang

Classifications

• H10P14/44

  Physical vapour deposition [PVD] · CPC title

• H10D64/0112

  using conductive layers comprising silicides · CPC title

• H10W20/4403

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

• H10W20/0698

  Local interconnections · CPC title

• H10W20/0526

  by thermal treatment thereof · CPC title