Cobalt-tungsten alloy and method of fabricating the same

Patent metadata

Field	Value
Publication number	US-12203154-B2
Application number	US-202318476663-A
Country	US
Kind code	B2
Filing date	Sep 28, 2023
Priority date	May 29, 2020
Publication date	Jan 21, 2025
Grant date	Jan 21, 2025

Abstract

Disclosed are a cobalt-tungsten alloy and a method of fabricating the same. More particularly, cobalt-tungsten alloy nanowires according to an embodiment are formed using an electroplating method, a grain structure of the cobalt-tungsten alloy nanowires is controlled according to the content of tungsten, and the electrical resistivity of the cobalt-tungsten alloy nanowires can be reduced through annealing.

First claim

What is claimed is:

1. A method of fabricating cobalt-tungsten alloy nanowires, the method comprising:
forming cobalt-tungsten (Co—W) alloy nanowires on a nanotemplate using an electroplating method; and
annealing the formed alloy nanowires,
wherein, in the forming, a grain structure of the alloy nanowires is controlled according to a content of tungsten,
wherein a content of tungsten in the cobalt-tungsten alloy nanowires is 25.1 at. % to control the grain structure of the alloy nanowires to have an amorphous-like structure,
wherein, in the forming, the cobalt-tungsten alloy nanowires are formed using the electroplating method in an environment, in which a current density of 5.00 mA/cm 2 is applied to simultaneously reduce cobalt and the tungsten,
wherein the content of tungsten is controlled by using a deionized water-based solution comprising cobalt sulfate heptahydrate (CoSO 4 ·7H 2 O), sodium tungstate heptahydrate (Na 2 WO 4 ·7H 2 O), boric acid (H 3 BO 3 ), citric acid (C 6 H 8 O 7 ), and sodium citrate tribasic dihydrate (C 6 H 7 Na 3 O 8 ), and
wherein concentrations of the sodium tungstate heptahydrate (Na 2 WO 4 ·7H 2 O) and the sodium citrate tribasic dihydrate (C 6 H 7 Na 3 O 8 ) are 0.20 mol/L and 0.50 mol/L, respectively.

2. The method according to claim 1 , wherein, in the annealing, a cobalt-tungsten intermetallic compound is formed through the annealing and thus electrical resistivity of the Co—W alloy nanowires is reduced.

3. The method according to claim 1 , wherein the annealing is performed at 400° C. to 600° C.

4. The method according to claim 1 , wherein the nanotemplate comprises a polycarbonate membrane (PCM) or anodic aluminum oxide (AAO) and at least one nano-porous track is formed in the nanotemplate.

5. The method according to claim 1 , further comprising separating the annealed alloy nanowires from the nanotemplate.

6. A method of fabricating cobalt-tungsten alloy nanowires, the method comprising:
forming cobalt-tungsten (Co—W) alloy nanowires on a nanotemplate using an electroplating method; and
annealing the formed alloy nanowires,
wherein, in the forming, a grain structure of the alloy nanowires is controlled according to a content of tungsten,
wherein a content of tungsten in the cobalt-tungsten alloy nanowires is 15.8 at. % to 19.1 at. % to control the grain structure of the alloy nanowires to have an amorphous-like structure,
wherein, in the forming, the cobalt-tungsten alloy nanowires are formed using the electroplating method in an environment, in which a current density of 1.25 mA/cm 2 to 5.00 mA/cm 2 is applied to simultaneously reduce cobalt and the tungsten,
wherein the content of tungsten is controlled by using a deionized water-based solution comprising cobalt sulfate heptahydrate (CoSO 4 ·7H 2 O), sodium tungstate heptahydrate (Na 2 WO 4 ·7H 2 O), boric acid (H 3 BO 3 ), citric acid (C 6 H 8 O 7 ), and sodium citrate tribasic dihydrate (C 6 H 7 Na 3 O 8 ), and
wherein concentrations of the sodium tungstate heptahydrate (Na 2 WO 4 ·7H 2 O) and the sodium citrate tribasic dihydrate (C 6 H 7 Na 3 O 8 ) are 0.10 mol/L to 0.20 mol/L and 0.50 mol/L, respectively.

7. The method according to claim 6 , wherein, in the annealing, a cobalt-tungsten intermetallic compound is formed through the annealing and thus electrical resistivity of the Co—W alloy nanowires is reduced.

8. The method according to claim 6 , wherein the annealing is performed at 400° C. to 600° C.

9. The method according to claim 6 , wherein the nanotemplate comprises a polycarbonate membrane (PCM) or anodic aluminum oxide (AAO) and at least one nano-porous track is formed in the nanotemplate.

10. The method according to claim 6 , further comprising separating the annealed alloy nanowires from the nanotemplate.

Assignees

• Univ Korea Res & Bus Found

Inventors

• Kim Young Keun
• Yoo Eun Min
• Moon Jun Hwan
• Jeon Yoo Sang

Classifications

• C25D5/50

  by heat-treatment · CPC title

• C25D3/562 Primary

  containing more than 50% by weight of iron or nickel or cobalt · CPC title

• B82Y40/00

  Manufacture or treatment of nanostructures · CPC title

• B82Y30/00

  Nanotechnology for materials or surface science, e.g. nanocomposites · CPC title

• B22F1/142

  Thermal or thermo-mechanical treatment · CPC title