High resistivity iron-based, thermally stable magnetic material for on-chip integrated inductors

Patent metadata

Field	Value
Publication number	US-9793336-B2
Application number	US-201715410987-A
Country	US
Kind code	B2
Filing date	Jan 20, 2017
Priority date	Mar 24, 2015
Publication date	Oct 17, 2017
Grant date	Oct 17, 2017

Abstract

An on-chip magnetic structure includes a palladium activated seed layer and a substantially amorphous magnetic material disposed onto the palladium activated seed layer. The substantially amorphous magnetic material includes nickel in a range from about 50 to about 80 atomic % (at. %) based on the total number of atoms of the magnetic material, iron in a range from about 10 to about 50 at. % based on the total number of atoms of the magnetic material, and phosphorous in a range from about 0.1 to about 30 at. % based on the total number of atoms of the magnetic material. The magnetic material can include boron in a range from about 0.1 to about 5 at. % based on the total number of atoms of the magnetic material.

First claim

What is claimed is:

1. A method for forming an on-chip magnetic structure, the method comprising:
activating a magnetic seed layer with palladium, the magnetic seed layer being positioned over a substrate; and
electrolessly plating a soft magnetic alloy onto the palladium in the presence of a magnetic field bias;
wherein the soft magnetic alloy comprises nickel in a range from about 50 to about 80 at % based on the total number of atoms of the soft metallic alloy, iron in a range from about 10 to about 50 at. % based on the total number of atoms of the soft metallic alloy, phosphorous in a range from about 0.1 to about 30 at. % based on the total number of atoms in the soft metallic alloy, and boron in a range from about 0.1 to about 5 at. % based on the total number of atoms of the soft magnetic alloy.

2. The method of claim 1 , wherein activating the magnetic seed layer comprises exposing the magnetic seed layer to a solution comprising palladium.

3. The method of claim 2 , wherein the solution further comprises an acid.

4. The method of claim 3 , wherein the palladium is present in an amount in a range from about 45 to about 65 ppm.

5. The method of claim 3 , wherein the acid is sulfuric acid, hydrochloric acid, nitric acid, or any combination thereof.

6. The method of claim of claim 1 , wherein the soft metallic alloy's resistivity is at least 110 μΩ·cm.

7. The method of claim 1 , wherein the magnetic field bias is in a range from about 0.1 to about 1.5 Tesla.

8. The method of claim 1 , wherein the soft magnetic alloy's coercivity is about or less than about 1 oersted (Oe).

9. The method of claim 1 , wherein the magnetic seed layer comprises nickel.

10. The method of claim 9 , wherein the magnetic seed layer further comprises an iron layer.

11. The method of claim 1 , wherein the on-chip magnetic structure is an inductor.

12. The method of claim 1 , wherein the magnetic seed layer comprises nickel in an amount in a range from about 0.1 to about 80 at. %.

13. The method of claim 1 , wherein the magnetic seed layer comprises iron in an amount in a range from about 0.1 to about 50 at. %.

14. The method of claim 1 , wherein the magnetic seed layer comprises about 80 wt. % nickel and about 20 wt. % iron.

15. The method of claim 1 , wherein the magnetic seed layer has a thickness in a range from about 50 to about 70 nm.

16. The method of claim 1 , wherein the magnetic seed layer further comprises a protective layer, and the protective layer is removed before electrolessly plating.

17. The method of claim 16 , wherein the protective layer is a metal or a non-metal.

18. The method of claim 17 , wherein the protective layer is the metal, and the metal is titanium.

19. The method of claim 1 , wherein activating the magnetic seed layer comprises immersing the substrate in a palladium sulfate solution.

20. The method of claim 1 , wherein activating the magnetic seed layer comprises immersing the substrate in a palladium salt solution.

Assignees

• IBM
• Int Busienss Machines Corp

Inventors

• Deligianni Hariklia
• Gallagher William J
• Mason Maurice
• O'Sullivan Eugene J
• Romankiw Lubomyr T
• Wang Naigang

Classifications

• H10P14/46

  using a liquid · 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

• H10W20/497

  Inductive arrangements or effects of, or between, wiring layers · CPC title

• H01L28/10 Primary

  Electricity · mapped topic