Buffer Layers And Interlayers That Promote BiSbx (012) Alloy Orientation For SOT And MRAM Devices

Patent metadata

Field	Value
Publication number	US-2023386721-A1
Application number	US-202318232256-A
Country	US
Kind code	A1
Filing date	Aug 9, 2023
Priority date	Aug 13, 2021
Publication date	Nov 30, 2023
Grant date	—

Abstract

The present disclosure generally relate to spin-orbit torque (SOT) magnetic tunnel junction (MTJ) devices comprising a buffer layer, a bismuth antimony (BiSb) layer having a (012) orientation disposed on the buffer layer, and an interlayer disposed on the BiSb layer. The buffer layer and the interlayer may each independently be a single layer of material or a multilayer of material. The buffer layer and the interlayer each comprise at least one of a covalently bonded amorphous material, a tetragonal (001) material, a tetragonal (110) material, a body-centered cubic (bcc) (100) material, a face-centered cubic (fcc) (100) material, a textured bcc (100) material, a textured fcc (100) material, a textured (100) material, or an amorphous metallic material. The buffer layer and the interlayer inhibit antimony (Sb) migration within the BiSb layer and enhance uniformity of the BiSb layer while further promoting the (012) orientation of the BiSb layer.

First claim

What is claimed is:

1 . A spin-orbit torque (SOT) device, comprising:
a substrate; a bismuth antimony (BiSb) layer disposed over the substrate, the BiSb layer having a ( 012 ) orientation; and a multilayer structure disposed in contact with the BiSb layer, the multilayer structure comprising:
an amorphous sublayer comprising a material in an amorphous structure, wherein the material comprises a carbide, a oxide, or a nitride, and wherein the material in the amorphous sublayer has a lattice constant of a crystal structure (afcc) between about 3.5 Å and 3.71 Å.

2 . The SOT device of claim 1 , wherein the multilayer structure further comprises one or more sublayers in addition to the amorphous sublayer, each of the one or more sublayers comprising one or more materials selected from the group consisting of: a tetragonal ( 001 ) material, a tetragonal ( 110 ) material, a body-centered cubic (bcc) ( 100 ) material, a face-centered cubic (fcc) ( 100 ) material, a textured bcc ( 100 ) material, a textured fcc ( 100 ) material, a textured ( 100 ) material, an amorphous metallic material, and a layered combination of one or more of any of the preceding materials.

3 . The SOT device of claim 1 , wherein the multilayer structure is a buffer layer or an interlayer.

4 . The SOT device of claim 1 , wherein the material of the amorphous sublayer of the multilayer structure has a nearest neighbor distance equal to about afcc divided by the square root of 3.

5 . The SOT device of claim 1 , wherein a nearest neighbor distance of the material of the amorphous sublayer of the multilayer structure is about 2.0 Å to about 2.2 Å.

6 . The SOT device of claim 1 , wherein amorphous sublayer comprises one or more materials selected from the group consisting of: ScC, TiC, NbC, ZrC, HfC, TaC, FeO, CoO, ZrO, MgO, TiO, TiN, NbN, ZrN, HfN, and TaN.

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

8 . A magnetic recording device comprising the magnetic recording head of claim 7 .

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

10 . A spin-orbit torque (SOT) device, comprising:
a substrate; a multilayer structure disposed over the substrate, the multilayer structure comprising:
at least one first intermediary layer, the at least one first intermediary layer comprising at least one of: a tetragonal ( 001 ) material, a tetragonal ( 110 ) material, a body-centered cubic (bcc) ( 100 ) material, a face-centered cubic (fcc) ( 100 ) material, a textured bcc ( 100 ) material, a textured fcc ( 100 ) material, a textured ( 100 ) material, and an amorphous material comprising a carbide, an oxide, or a nitride; and
a bismuth antimony (BiSb) layer stack disposed in contact with the multilayer structure, the antimony (BiSb) layer stack comprising:
a BiSb layer having a ( 012 ) orientation
a first Bi layer, wherein the BiSb layer is disposed on the first Bi layer, and
a second Bi layer disposed on the BiSb layer,
wherein the first and second Bi layers sandwich the BiSb layer.

11 . The SOT device of claim 10 , wherein the first and second Bi layers each has a thickness greater than about 0.1 Å and less than about 10 Å.

12 . The SOT device of claim 10 , wherein the multilayer structure further comprises an amorphous layer disposed below the first intermediary layer, the amorphous layer comprising a material selected from the group consisting of: NiTa, NiFeTa, NiNb, NiW, NiFeW, NiFeHf, CoHfB, CoZrTa, CoFeB, NiFeB, CoB, FeB, and alloy combinations thereof with elements selected from the group consisting of: Ni, Fe, Co, Zr, W, Ta, Hf, Ag, Pt, Pd, Si, Ge, Mn, Al, and Ti.

13 . The SOT device of claim 10 , wherein the multilayer structure further comprises at least one second intermediary layer comprising a textured bcc ( 100 ) material or a textured fcc ( 100 ) material.

14 . The SOT device of claim 10 , wherein the multilayer structure is a buffer layer or an interlayer.

15 . A magnetic recording head comprising the SOT device of claim 10 .

16 . A magnetic recording device comprising the magnetic recording head of claim 15 .

17 . A magneto-resistive memory comprising the SOT device of claim 10 .

18 . A spin-orbit torque (SOT) device, comprising:
a substrate; a multilayer structure disposed over the substrate, the multilayer structure comprising:
a textured layer with a ( 100 ) orientation; and
a first intermediary layer disposed over the textured layer, the first intermediary layer comprising at least one of: a tetragonal ( 001 ) material, a tetragonal ( 110 ) material, a body-centered cubic (bcc) ( 100 ) material, a face-centered cubic (fcc) ( 100 ) material, a textured bcc ( 100 ) material, a textured fcc ( 100 ) material, a textured ( 100 ) material, and an amorphous material comprising a carbide, an oxide, or a nitride; and
a bismuth antimony (BiSb) layer disposed in contact with the multilayer structure, the BiSb layer having a ( 012 ) orientation.

19 . The SOT device of claim 18 , wherein the multilayer structure further comprises an amorphous layer comprising a material selected from the group consisting of: NiTa, NiFeTa, NiNb, NiW, NiFeW, NiFeHf, CoHfB, CoZrTa, CoFeB, NiFeB, CoB, FeB, and alloy combinations thereof with elements selected from the group consisting of: Ni, Fe, Co, Zr, W, Ta, Hf, Ag, Pt, Pd, Si, Ge, Mn, Al, and Ti, wherein the amorphous layer is disposed over the substrate, the textured layer is disposed on the amorphous layer, the first intermediary layer is disposed on the textured layer, and the BiSb layer is disposed on the first intermediary layer.

20 . The SOT device of claim 18 , wherein the textured layer comprises a material selected from the group consisting of:
RuAl, Cr, and Cr:
in heated CrX alloys where X is Ru, Mo, W, or Ti in less than about atomic percent,
as CrMo n where n is about 20 atomic percent to about 50 atomic percent, or
in a layer stack of Cr and CrMo n or CrMo n , Cr, and CrMo n where n is about 20 atomic percent to about 50 atomic percent.

21 . The SOT device of claim 18 , wherein the multilayer structure further comprises one or more second intermediary layers, the one or more second intermediary layers having a cubic crystal structure different than the first intermediary layer.

22 . A magnetic recording head comprising the SOT device of claim 18 .

23 . A magnetic recording device comprising the magnetic recording head of claim 22 .

24 . A magneto-resistive memory comprising the SOT device of claim 18 .

Assignees

• Western Digital Tech Inc

Inventors

• Le Quang
• York Brian R
• Hwang Cherngye
• Okamura Susumu
• Gribelyuk Michael A
• Liu Xiaoyong
• Ho Kuok San
• Takano Hisashi

Classifications

• H10N50/80

  Constructional details · CPC title

• G11B2005/0024

  Microwave assisted recording · CPC title

• G11B5/314

  where the layers are extra layers normally not provided in the transducing structure, e.g. optical layers (G11B5/3196 takes precedence) · CPC title

• G11B5/235

  Selection of material for gap filler {(G11B5/232 takes precedence)} · CPC title

• G11B5/1278

  specially adapted for magnetisations perpendicular to the surface of the record carrier · CPC title