RuAl and MgTiO Lamination For Effective Buffer and Interlayers For Topological Material Layers

Patent metadata

Field	Value
Publication number	US-2025246353-A1
Application number	US-202519040639-A
Country	US
Kind code	A1
Filing date	Jan 29, 2025
Priority date	Jan 31, 2024
Publication date	Jul 31, 2025
Grant date	—

Abstract

The present disclosure generally relates to topological insulator (TI) or a topological semi-metal (TSM) based spin-orbit torque (SOT) devices. The SOT device comprises a buffer layer, a TI or TSM layer, an interlayer, and a ferromagnetic layer. The buffer layer comprising a texture layer structure, where the texture layer structure comprises one or more of: (1) two or more laminated layers of RuAl and MgTiO or MgO, (2) laminations of MgO and W, (3) W-X body-centered cubic (bcc) alloys, where X is one or more of Ta, Hf, Ti, V, Nb, and Mo, or (4) combinations thereof. The texture layer structure has a (100) orientation. The TI or TSM layer comprises BiSb having a (012) orientation or YPtBi having a (100) orientation. The buffer layer may further comprise one or more body-centered cubic layers and an oxide layer.

First claim

What is claimed is:

1 . A spin-orbit torque (SOT) device, comprising:
a texture layer structure having a (100) orientation, the texture layer structure comprising one of more of:
(1) two or more laminated layers of RuAl and MgTiO or MgO;
(2) laminations of MgO and W; or
(3) W-X body-centered cubic (bcc) alloys, where X is one or more of Ta, Hf, Ti, V, Nb, and Mo; and
a topological insulator (TI) or a topological semi-metal (TSM) layer disposed over the texture layer structure.

2 . The SOT device of claim 1 , wherein the TI or TSM layer comprises BiSb having a (012) orientation.

3 . The SOT device of claim 1 , wherein the texture layer structure comprises the two or more laminated layers of RuAl and MgTiO or MgO.

4 . The SOT device of claim 1 , further comprising:
an interlayer; and a ferromagnetic layer.

5 . The SOT device of claim 1 , wherein the texture layer structure comprises the two or more laminated layers of RuAl and MgTiO or MgO, wherein the RuAl of each laminated layer has a thickness of about 25 Å to about 35 Å, and wherein the MgTiO or MgO of each laminated layer has a thickness of about 5 Å to about 15 Å.

6 . The SOT device of claim 1 , further comprising:
a barrier layer disposed between the texture layer structure and the TI or TSM layer; and an oxide layer disposed between the barrier layer and the TI or TSM layer.

7 . The SOT device of claim 1 , wherein the texture layer structure comprises the laminations of MgO and W.

8 . The SOT device of claim 1 , wherein the texture layer structure comprises the W-X body-centered cubic (bcc) alloys, where X is one or more of Ta, Hf, Ti, V, Nb, and Mo.

9 . A magnetic recording head comprising the SOT device of claim 1 .

10 . A magnetic recording device comprising the magnetic recording head of claim 9 .

11 . A magneto-resistive memory comprising the SOT device of claim 1 .

12 . A spin-orbit torque (SOT) device, comprising:
a seed layer comprising an amorphous material; a texture layer structure having a (100) orientation disposed on the seed layer, the texture layer structure comprising one or more of:
(1) two or more laminated layers of RuAl and MgTiO or MgO;
(2) laminations of MgO and W; or
(3) W-X body-centered cubic (bcc) alloys, where X is one or more of Ta, Hf, Ti, V, Nb, and Mo;
a topological insulator (TI) or a topological semi-metal (TSM) layer disposed over the texture layer structure; an interlayer disposed on the TI or TSM layer; and a ferromagnetic layer disposed on the interlayer.

13 . The SOT device of claim 12 , wherein the texture layer structure has a thickness of about 10 Å to about 150 Å.

14 . The SOT device of claim 12 , wherein the two or more laminated layers of RuAl and MgTiO or MgO comprises:
a first RuAl layer disposed on the seed layer; a first MgTiO or MgO layer disposed on the first RuAl layer; a second RuAl layer disposed on the first MgTiO or MgO layer; a second MgTiO or MgO layer disposed on the second RuAl layer; and a third RuAl layer disposed on the second MgTiO or MgO layer.

15 . The SOT device of claim 12 , wherein the TI or TSM layer comprises BiSb having a (012) orientation or YPtBi having a (100) orientation.

16 . The SOT device of claim 12 , wherein the texture layer structure comprises two or more laminated layers of RuAl and MgTiO or MgO, and wherein the RuAl of each laminated layer has a greater thickness than the MgTiO or MgO of each laminated layer.

17 . The SOT device of claim 12 , wherein the texture layer structure comprises the laminations of MgO and W.

18 . The SOT device of claim 12 , wherein the texture layer structure comprises the W-X body-centered cubic (bcc) alloys, where X is one or more of Ta, Hf, Ti, V, Nb, and Mo.

19 . The SOT device of claim 12 , wherein the two or more laminated layers of RuAl and MgTiO or MgO comprises:
a first RuAl layer disposed on the seed layer; a first MgTiO or MgO layer disposed on the first RuAl layer; a second RuAl layer disposed on the first MgTiO or MgO layer; a second MgTiO or MgO layer disposed on the second RuAl layer; a third RuAl layer disposed on the second MgTiO or MgO layer; a third MgTiO or MgO layer disposed on the third RuAl layer; and a fourth RuAl layer disposed on the third MgTiO or MgO layer.

20 . A magnetic recording head comprising the SOT device of claim 12 .

21 . A magnetic recording device comprising the magnetic recording head of claim 20 .

22 . A magneto-resistive memory comprising the SOT device of claim 12 .

23 . A spin-orbit torque (SOT) device, comprising:
a buffer layer comprising:
a texture layer structure having a (100) orientation disposed on a seed layer, the texture layer structure comprising one or more of:
(1) two or more laminated layers of RuAl and MgTiO or MgO;
(2) laminations of MgO and W;
(3) W-X body-centered cubic (bcc) alloys, where X is one or more of Ta, Hf, Ti, V, Nb, and Mo;

a first barrier layer disposed on the texture layer structure; and
an oxide layer disposed on the first barrier layer;
a topological insulator (TI) or a topological semi-metal (TSM) layer disposed over the texture layer structure; an interlayer disposed on the TI or TSM layer; and a ferromagnetic layer disposed on the interlayer.

24 . The SOT device of claim 23 , wherein the first barrier layer comprises W, and wherein the oxide layer comprises MgTiO.

25 . The SOT device of claim 24 wherein the first barrier layer has a thickness of about 40 Å to about 60 Å, and wherein the oxide layer has a thickness of about 5 Å to about 50 Å.

26 . The SOT device of claim 23 , wherein the texture layer structure comprises two or more laminated layers of RuAl and MgTiO or MgO, and wherein the RuAl of each laminated layer has a greater thickness than the MgTiO or MgO of each laminated layer.

27 . The SOT device of claim 23 , wherein the TI or TSM layer comprises BiSb having a (012) orientation or YPtBi having a (100) orientation.

28 . The SOT device of claim 23 , further comprising a second barrier layer disposed between the oxide layer and the TI or TSM layer.

29 . The SOT device of claim 23 , wherein the texture layer structure comprises the laminations of MgO and W.

30 . The SOT device of claim 23 , wherein the texture layer structure comprises the W-X body-centered cubic (bcc) alloys, where X is one or more of Ta, Hf, Ti, V, Nb, and Mo.

31 . The SOT device of claim 23 , wherein the texture layer structure comprises the two or more laminated layers of RuAl and MgTiO or MgO.

32 . A magnetic recording head comprising the SOT device of claim 23 .

33 . A magnetic recording device comprising the magnetic recording head of claim 32 .

34 . A magneto-resistive memory comprising the SOT device of claim 23 .

Assignees

• Western Digital Tech Inc

Inventors

• Le Quang
• York Brian R
• Gribelyuk Michael A
• Liu Xiaoyong
• Le Son T
• Maeda Maki
• Takano Hisashi

Classifications

• H10N50/85

  Materials of the active region · CPC title

• H10N50/10

  Magnetoresistive devices · CPC title

• H01F10/329 Primary

  Spin-exchange coupled multilayers wherein the magnetisation of the free layer is switched by a spin-polarised current, e.g. spin torque effect · CPC title

• G11B5/39

  using magneto-resistive devices {or effects} · CPC title

• H10B61/20 Primary

  comprising components having three or more electrodes, e.g. transistors · CPC title