Magnetic head and magnetic recording device

Patent metadata

Field	Value
Publication number	US-11615808-B2
Application number	US-202117397188-A
Country	US
Kind code	B2
Filing date	Aug 9, 2021
Priority date	Feb 25, 2021
Publication date	Mar 28, 2023
Grant date	Mar 28, 2023

Abstract

According to one embodiment, a magnetic head includes first and second magnetic poles, and a stacked body provided between the first and second magnetic poles. The stacked body includes a first magnetic layer, a second magnetic layer provided between the second magnetic pole and the first magnetic layer, a third magnetic layer provided between the second magnetic pole and the second magnetic layer, a first non-magnetic layer provided between the first magnetic layer and the first magnetic pole, a second non-magnetic layer provided between the second and first magnetic layers, a third non-magnetic layer provided between the third and second magnetic layers, and a fourth non-magnetic layer provided between the second magnetic pole and the third magnetic layer. A thickness of the first magnetic layer is thicker than a thickness of the second magnetic layer. A thickness of the third magnetic layer is thicker than the second layer thickness.

First claim

What is claimed is:

1. A magnetic head comprising:
a first magnetic pole;
a second magnetic pole; and
a stacked body provided between the first magnetic pole and the second magnetic pole,
the stacked body including
a first magnetic layer,
a second magnetic layer provided between the second magnetic pole and the first magnetic layer,
a third magnetic layer provided between the second magnetic pole and the second magnetic layer,
a first non-magnetic layer provided between the first magnetic layer and the first magnetic pole,
a second non-magnetic layer provided between the second magnetic layer and the first magnetic layer,
a third non-magnetic layer provided between the third magnetic layer and the second magnetic layer, and
a fourth non-magnetic layer provided between the second magnetic pole and the third magnetic layer, wherein
the first non-magnetic layer contacts the first magnetic layer and the first magnetic pole,
the second non-magnetic layer contacts the second magnetic layer and the first magnetic layer,
the third non-magnetic layer contacts the third magnetic layer and the second magnetic layer, and
the fourth non-magnetic layer contacts the second magnetic pole and the third magnetic layer,

a first thickness of the first magnetic layer along a first direction from the first magnetic pole toward the second magnetic pole being thicker than a second thickness of the second magnetic layer along the first direction, and
a third thickness of the third magnetic layer along the first direction being thicker than the second thickness.

2. The head according to claim 1 , wherein
the third thickness is not less than 0.6 times and not more than 1.7 times the first thickness.

3. The head according to claim 1 , wherein
the third thickness is not less than 0.8 times and not more than 1.25 times the first thickness.

4. The head according to claim 1 , wherein
the second thickness is not more than 0.7 times the first thickness.

5. The head according to claim 1 , wherein
the second thickness is not more than 0.5 times the first thickness.

6. The head according to claim 1 , wherein
the second thickness is not more than 0.7 times the third thickness.

7. The head according to claim 1 , wherein
the second thickness is not more than 0.5 times the third thickness.

8. The head according to claim 1 , wherein
the first thickness is not less than 5 nm and not more than 15 nm.

9. The head according to claim 1 , wherein
the third thickness is not less than 5 nm and not more than 15 nm.

10. The head according to claim 1 , wherein
the first non-magnetic layer includes at least one selected from the group of consisting Cu, Au, Cr, Al, V and Ag, and
the fourth non-magnetic layer includes at least one selected from the group consisting of Ru, Ir, Ta, Rh, Pd, Pt and W.

11. The head according to claim 1 , wherein
the third non-magnetic layer includes at least one selected from the group of consisting Cu, Au, Cr, Al, V and Ag, and
the second non-magnetic layer includes at least one selected from the group consisting of Ru, Ir, Ta, Rh, Pd, Pt and W.

12. The head according to claim 1 , wherein
the first magnetic layer, the second magnetic layer and the third magnetic layer include at least one element including at least one selected from the group consisting of Fe, Co, and Ni.

13. The head according to claim 12 , wherein
the first magnetic layer, the second magnetic layer and the third magnetic layer do not include a second element including at least one selected from the group consisting of Cr, V, Mn, Ti and Sc, or a concentration of the second element in the first magnetic layer, the second magnetic layer and the third magnetic layer is less than 10 atm %.

14. The head according to claim 1 , wherein
a current having a direction from the first magnetic layer toward the second magnetic layer is supplied to the stacked body.

15. The head according to claim 14 , wherein
when the current is supplied to the stacked body, an alternating magnetic field is generated from the stacked body.

16. The head according to claim 1 , wherein
when a current having a direction from the first magnetic layer toward the second magnetic layer is supplied to the stacked body, a first magnetization of the first magnetic layer and a third magnetization of the third magnetic layer rotate in reverse phases.

17. The head according to claim 1 , further comprising:
a first terminal; and a second terminal,
the first terminal being electrically connected to a portion of the stacked body,
the second terminal being electrically connected to another portion of the stacked body, and
a current being configured to be supplied between the first terminal and the second terminal.

18. A magnetic recording device comprising:
the magnetic head according to claim 1 ; and
an electric circuit,
the electric circuit being configured to supply a current to the stacked body, and
the current having a direction from the first magnetic layer toward the second magnetic layer.

19. The device according to claim 18 , wherein
when the electric circuit supplies the current to the stacked body, an alternating magnetic field is generated from the stacked body.

Assignees

• Toshiba Kk
• Toshiba Electronic Devices & Storage Corp

Inventors

• Nakagawa Yuji
• Narita Naoyuki
• Takagishi Masayuki
• Maeda Tomoyuki
• Nagasawa Tazumi
• Suto Hirofumi

Classifications

• H10D48/40

  Devices controlled by magnetic fields · CPC title

• G11B5/23 Primary

  Gap features {(G11B5/1871, G11B5/1875, G11B5/265, G11B5/29, G11B5/488 and subgroups, G11B5/4907 and subgroups, G11B5/4969 and subgroups take precedence)} · CPC title

• G11B5/1877 Primary

  including at least one magnetic thin film · CPC title

• G11B5/488

  Disposition of heads (G11B5/49, G11B5/52 take precedence) · CPC title

• G11B2005/0024

  Microwave assisted recording · CPC title