IP Library Granted Patent US 9,818,535
Granted Patent B2
US 9,818,535 · App. 14/592,152 · Granted Nov 14, 2017

Systems and methods for locally reducing oxides

Inventors: Dmitri Litvinov (Friendswood, TX); Long Chang (Pearland, TX)
Assignee: UNIVERSITY OF HOUSTON SYSTEM
H01F41/22C23C14/0036C23C14/085C23C14/5806C23C14/5846G11B5/65G11B5/855H01F10/123H01F10/14H01F10/16
View Patent ↗
Loading inventors, assignments & file history…
Monitor This Case
Get email alerts when status or documents change.
Order Certified Copies
Most orders are placed with the USPTO same day — all within 24 business hours.
Order via The Patent Place →
Pre-filled with this patent's details
Quick Facts
Patent No.
US 9,818,535
App. No.
14/592,152
Granted
Nov 14, 2017
Kind
B2
Abstract

In the systems and methods for synthesizing a thin film with desired properties (e.g. magnetic, conductivity, photocatalyst, etc.), a metal oxide film may be deposited on a substrate. The metal oxide film may be achieved utilizing any suitable method. A reducing agent may be deposited before, after or both before and after the metal oxide layer. Oxygen may be removed or liberated from the deposited metal oxide film by low temperature local or global annealing. As a result of the annealing to remove oxygen, one or more portions of the metal oxide may be transformed into materials with desired properties. As a nonlimiting example, a metal oxide film may be treated to provide a magnetic multilayer film that is suitable for bit patterned media.

Claims (28)

1. A method for reducing a metal oxide layer, the method comprising:

depositing a metal oxide layer on a substrate;

depositing a reducing agent on the substrate to aid removal of oxygen from the metal oxide layer; and

annealing the substrate to remove oxygen from the metal oxide layer, wherein the annealing step comprises heating localized areas to pattern the metal oxide layer thereby resulting in the metal oxide layer providing one or more patterned islands with oxygen removed, wherein further the metal oxide layer is a cobalt oxide, CoO, CoOPd, CoOPt, Fe 2 O 3 , Fe 3 O 4 , iron oxide, TiO 2 , tin oxide, manganese oxide, chromium oxide, nickel oxide, silver oxide, or molybdenum oxide, and the annealing results in a change in magnetism, conductivity, photocatalyst, or refractive index properties of the metal oxide layer.

2. The method of claim 1 , wherein the metal oxide layer is a patterned layer.

3. The method of claim 1 , wherein the reducing agent is deposited before, after, or both before and after the metal oxide layer.

4. The method of claim 1 , wherein the reducing agent is Ta, Al, Mg, Ca, Zr, Zn, Ti, Si, or C.

5. The method of claim 1 , wherein an annealing time is equal to or between 0.1 nanoseconds to 24 hours.

6. The method of claim 1 , wherein an annealing time is 5 minutes or greater.

7. The method of claim 1 , wherein an annealing temperature is equal to or greater than 100° C.

8. The method of claim 1 , wherein an annealing temperature is equal to or between 100-1000° C.

9. The method of claim 1 , wherein an annealing temperature is equal to or between 100° C. to 500° C.

10. The method of claim 1 wherein the metal oxide layer is a cobalt oxide, CoO, CoOPd, CoOPt, iron oxide, Fe 2 O 3 , Fe 3 O 4 , or nickel oxide.

11. The method of claim 1 , wherein the substrate and the annealed metal oxide layer are bit patterned media (BPM).

12. The method of claim 11 , wherein the BPM has a defect density of 15% or less variation in switching properties.

13. The method of claim 11 , wherein the BPM has a defect density of 10% or less variation in switching properties.

14. The method of claim 11 , wherein the BPM has a defect density of 5% or less variation in switching properties.

15. The method of claim 1 , wherein the annealing results in a change in magnetism, photocatalyst, or refractive index properties of the metal oxide layer.

16. A method for forming bit pattern media (BPM), the method comprising:

depositing a media layer comprising a metal oxide on a substrate, wherein the metal oxide demonstrates magnetic properties when oxygen is removed;

depositing a reducing agent on the media layer to aid removal of oxygen; and

locally annealing the media layer, wherein the local annealing heats a plurality of regions of the media layer and the plurality of regions form a matrix of magnetic islands.

17. The method of claim 16 , wherein the metal oxide is a cobalt oxide, CoO, CoOPd, CoOPt, iron oxide, Fe 2 O 3 , Fe 3 O 4 , or nickel oxide.

18. The method of claim 16 , wherein a second reducing agent is deposited before, after or both before and after the media layer.

19. The method of claim 16 , wherein the reducing agent is Ta, Al, Mg, Ca, Zr, Zn, Ti, Si, or C.

20. The method of claim 16 , wherein an annealing time is equal to or between 0.1 nanoseconds to 24 hours.

21. The method of claim 16 , wherein an annealing temperature is equal to or greater than 100° C.

22. The method of claim 16 , wherein the BPM has a defect density of 15% or less variation in switching properties.

Assignments (3)
CONFIRMATORY LICENSE Recorded Apr 16, 2025
From: UNIVERSITY OF HOUSTON
To: NATIONAL SCIENCE FOUNDATION
Reel/Frame 070864/0135 →
CONFIRMATORY LICENSE Recorded Jun 20, 2023
From: UNIVERSITY OF HOUSTON
To: NSF - DEITR
Reel/Frame 064002/0816 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Jun 18, 2015
From: LITVINOV, DMITRI; CHANG, LONG
To: UNIVERSITY OF HOUSTON SYSTEM
Reel/Frame 035863/0057 →
Continuity (3)
Provisional Application 61924933 · Jan 8, 2014
Provisional Application 61977909 · Apr 10, 2014
Related Publication 20150194261A1 · Jul 9, 2015