Western Digital Technologies, Inc.

Hisashi Takano

Quang Le

Zhigang Bai

Cherngye Hwang

Kuok San Ho

Zhanjie Li

Brian Rodrick York

Xiaoyong Liu

Randy G Simmons

Susumu Okamura

Michael Gribelyuk

Xiaoyu Xu

The present disclosure generally relates to spin-orbit torque (SOT) device comprising a first bismuth antimony (BiSb) layer having a (001) orientation. The SOT device comprises a first BiSb layer having a (001) orientation and a second BiSb layer having a (012) orientation. The first BiSb layer having a (001) orientation is formed by depositing an amorphous material selected from the group consisting of: B, Al, Si, SiN, Mg, Ti, Sc, V, Cr, Mn, Y, Zr, Nb, AlN, C, Ge, and combinations thereof, on a substrate, exposing the amorphous material to form an amorphous oxide surface on the amorphous material, and depositing the first BiSb layer on the amorphous oxide surface. By utilizing a first BiSb layer having a (001) orientation and a second BiSb having a (012) orientation, the signal through the SOT device is balanced and optimized to match through both the first and second BiSb layers.

Highly textured 001 BiSb and materials for making same

The present disclosure generally relates to spin-orbit torque (SOT) magnetic tunnel junction (MTJ) devices comprising a doped bismuth antimony (BiSbE) layer having a () orientation. The devices may include magnetic write heads, read heads, or MRAM devices. The dopant in the BiSbE layer enhances the () orientation. The BiSbE layer may be formed on a texturing layer to ensure the () orientation, and a migration barrier may be formed over the BiSbE layer to ensure the antimony does not migrate through the structure and contaminate other layers. A buffer layer and interlayer may also be present. 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 inhibit antimony (Sb) migration within the doped BiSbE layer and enhance uniformity of the doped BiSbE layer while further promoting the () orientation of the doped BiSbE layer.

Doping process to refine grain size for smoother BiSb film surface

The present disclosure generally relates to spin-orbit torque (SOT) devices comprising a bismuth antimony (BiSb) layer. The SOT devices further comprise one or more GeNiFe layers, where at least one GeNiFe layer is disposed in contact with the BiSb layer. The GeNiFe layer has a thickness less than or equal to about 15 Å when used as an interlayer on top of the BiSb layer or less than or equal to 40 Å when used as a buffer layer underneath the BiSb. When the BiSb layer is doped with a dopant comprising a gas, a metal, a non-metal, or a ceramic material, the GeNiFe layer promotes the BiSb layer to have a (012) orientation. When the BiSb layer is undoped, the GeNiFe layer promotes the BiSb layer to have a (001) orientation. Utilizing the GeNiFe layer allows the crystal orientation of the BiSb layer to be selected.

Doped BiSb (012) or undoped BiSb (001) topological insulator with GeNiFe buffer layer and/or interlayer for SOT based sensor, memory, and storage devices

Embodiments of the present disclosure relate to a cobalt-boron (CoB) layer for magnetic recording devices, memory devices, and storage devices. In one or more embodiments, the CoB layer is part of a spin-orbit torque (SOT) device. In one or more embodiments, the SOT device is part of an SOT based sensor, an SOT based writer, a memory device (such as a magnetoresistive random-access memory (MRAM) device), and/or a storage device (such as a hard disk drive (HDD) or a tape drive). In one embodiment, an SOT device includes a seed layer, and a cap layer spaced from the seed layer. The SOT device includes a spin-orbit torque (SOT) layer, and a nano layer (NL) between the seed layer and the cap layer. The SOT device includes a cobalt-boron (CoB) layer between the seed layer and the cap layer, and the CoB layer is ferromagnetic.

Cobalt-boron (CoB) layer for magnetic recording devices, memory devices, and storage devices

The present disclosure generally relate to spin-orbit torque (SOT) devices comprising a topological insulator (TI) modulation layer. The TI modulation layer comprises a plurality of bismuth or bismuth-rich composition modulation layers, a plurality of TI lamellae layers comprising BiSb having a (012) crystal orientation, and a plurality of texturing layers. The TI lamellae layers comprise dopants or clusters of atoms, the clusters of atoms comprising a carbide, a nitride, an oxide, or a composite ceramic material. The clusters of atoms are configured to have a grain boundary glass forming temperature of less than about 400° C. Doping the TI lamellae layers comprising BiSb having a (012) crystal orientation with clusters of atoms comprising a carbide, a nitride, an oxide, or a composite ceramic material enable the SOT MTJ device to operate at higher temperatures while inhibiting migration of Sb from the BiSb of the TI lamellae layers.

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San Jose, CA, United States of America

Hisashi Takano