Western Digital Technologies, Inc.

Hgst Netherlands, B.v.

Tokyo Institute of Technology

Xilinx, Inc.

Xiaoyong Liu

Quang Le

Kuok San Ho

Cherngye Hwang

Hisashi Takano

Brian Rodrick York

Zhanjie Li

Hongquan Jiang

Zhigang Bai

Daniele Mauri

Yukimasa Okada

Rajeev Nagabhirava

Yongchul Ahn

Son T Le

Nam Hai Pham

Michael Gribelyuk

Thao Anh Nguyen

Jui-lung Li

Guangli Liu

Ji Li

Randy G Simmons

Xiaoyu Xu

Fan Tuo

David John Seagle

Lei Wang

Susumu Okamura

Michael Ho

Goncalo Baiao De Albuquerque

Goncalo Marcos Baião De Albuquerque

Hassan Osman

Daniel Bai

Rohan Babu Nagabhirava

Zheng Gao

Ming Mao

Suping Song

Ying Hong

Chih-Ching Hu

Guanxiong Li

David Patrick Druist

Changhe Shang

Andrew Chen

Huy H Ho

Hardayal Singh Gill

Petrus Antonius Van Der Heijden

Yaguang Wei

Kumar Deepak

Chen-jung Chien

Yung-Hung Wang

Anup Roy

Jason Villarreal

Yunhe Huang

Shiwen Huang

Maki Maeda

Thomas L Leong

Gonçalo Marcos Baião De Albuquerque

Hongxue Liu

Alan Spool

Khang H D Nguyen

Julian Sasaki

Sharon Swee Ling Banh

Xiaohai Xiang

Songzi Wang

Wenqin Hao

Jinming Liu

Yu Tao

Xing-Cai Guo

The present disclosure generally relates to temperature detection devices including a ferromagnetic (FM) material disposed at a media facing surface (MFS). The FM material is configured to produce a first electric voltage signal in response to a temperature gradient due to an anomalous Nernst effect. The temperature detection device may also include a spin-orbit torque (SOT) material abutting the FM material. The SOT material includes at least one of BiSb, a topological insulator, a topological half-Heusler alloy, or a weakly oxidized heavy metal. The SOT material is recessed from the MFS, wherein the SOT material is configured to receive a spin current parallel to the temperature gradient generated by a spin Seebeck effect in the FM material. The spin current is detectable as a second electric voltage signal via an inverse spin Hall effect. The first electric voltage signal is added to the second electric voltage signal.

Spin orbit torque based thermal sensor for insitu monitoring of magnetic recording head

Nitrogen doping an insulating layer can lower the bandgap of a magnetic storage device. It is challenging to nitrogen dope magnesium oxide (MgO). A cation can be added to allow the magnesium to hold onto the nitrogen dopant without highly oxidizing or nitriding the cation. The resulting nitrogen doped MgXO, where X is the cation, has a lower bandgap compared to a much similar barrier layer that has neither nitrogen nor a cation thus improving thermal and electrical reliabilities. The nitrogen doped MgXO is non-stoichiometric whereas comparably, an oxynitride is stoichiometric. Example cations that may be used include aluminum, titanium, vanadium, chromium, and scandium.

Nitrogen doped oxides for lower bandgap

The present disclosure generally relates to a dual free layer two dimensional magnetic recording read head. The read head comprises a lower shield, a first sensor disposed over the first lower shield, a first rear hard bias (RHB) structure recessed from a media facing surface (MFS), a first upper shield disposed over the first sensor, a middle shield disposed over the first sensor at the MFS, a second sensor disposed over the middle shield, a second RHB structure recessed from the MFS, and an upper shield disposed over the second sensor. The middle shield has a U-like shape and a ratio of a width to a throat height of 6:1, where the throat height is less than or equal to about 2 μm. The first and second RHB structures each individually has a stripe height about 3 times greater than a stripe height of the middle shield.

DFL TDMR middle shield throat height control for improved stability

The present disclosure generally relates to a magnetic recording head comprising a read head. The read head comprises a first sensor disposed at a media facing surface (MFS) comprising at least one free layer, a second sensor disposed at the MFS comprising at least one free layer, a first spin generator spaced from the first sensor and recessed from the MFS, and a second spin generator spaced from the second sensor and recessed from the MFS. The first and second spin generators each individually comprises at least one spin orbit torque (SOT) layer. The SOT layer may comprise BiSb. The first and second sensors are configured to detect a read signal using a first voltage lead and a second voltage lead. The first and second spin generators are configured to inject spin current through non-magnetic layers to the first and second sensors using a plurality of current leads.

Non-localized spin valve multi-free-layer reader hybridized with spin orbit torque layers

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.

Buffer layers and interlayers that promote BiSbx (012) alloy orientation for sot and MRAM devices

The present disclosure generally relates to a magnetic sensor half bridge circuit. The half bridge circuit comprises a bias source connected to a first leg and a second leg. The first leg comprises one or more first spin-orbit torque (SOT) structures connected in series, each first SOT structure comprising a first ferromagnetic (FM) layer disposed on a first SOT layer. The first SOT layer has a first end connected to ground and a second end connected to a first voltage sensor. The second leg comprises one or more second SOT structures connected in series, each second SOT structure comprising a second FM layer disposed on a second SOT layer. The second SOT layer has a first end connected to a second voltage sensor and a second end connected to a ground. The first voltage sensor is disposed adjacent to the second voltage sensor.

Magnetic sensor half-bridge based on inverse spin hall effect with reduced thermal drift

The present disclosure generally relates to a magnetic recording head comprising a read head. The read head comprises a sensor disposed at a media facing surface (MFS) and a spin generator spaced from the sensor and recessed from the MFS. The sensor and spin generators are disposed on a non-magnetic layer. The sensor comprises a free layer and the spin generator comprises at least one spin orbit torque (SOT) layer. The SOT layer may comprise topological material such as BiSb. The sensor is configured to detect a read signal using a first voltage lead and a second voltage lead. The spin generator is configured to inject spin current through the non-magnetic layer to the sensor using a first current lead and a second current lead. The shape of the non-magnetic layer is a triangular or trapezoidal shape to further concentrate spin current.

Non-localized spin valve reader hybridized with spin orbit torque layer

The present disclosure generally relates to a magnetic media drive comprising a magnetic recording head. The magnetic recording head comprises a main pole disposed at a media facing surface (MFS), a shield disposed at the MFS, a spin blocking layer disposed between the shield and the main pole, at least one non-magnetic layer disposed between the main pole and the shield, the at least one non-magnetic layer being disposed at the MFS, and at least one spin orbit torque (SOT) layer disposed over the at least one non-magnetic layer, the SOT layer being recessed a distance of about 20 nm to about 100 nm from the MFS. A ratio of a length of the SOT layer to a thickness of the SOT layer is greater than 1. The at least one SOT layer comprises BiSb.

Higher areal density non-local spin orbit torque (SOT) writer with topological insulator materials

The present disclosure generally relates to spin-orbit torque (SOT) devices comprising a bismuth antimony (BiSb) layer. The SOT devices further comprises a first shield, a BiSb layer disposed over the first shield (S), a free layer (FL) disposed over the BiSb layer, and a second shield (S) disposed over the FL. The S, the FL, and the Sare disposed at a media facing surface (MFS). The BiSb layer is recessed from the MFS a first distance of about 5 nm to about 20 nm. The FL has a length greater than the first distance. A notch and/or an insulation layer is disposed adjacent to the BiSb layer at the MFS. Current may be configured to flow vertically through the Sto the FL, and horizontally from the FL to the BiSb layer. Current may be configured to flow vertically through the Sto the S

SOT reader with recessed SOT topological insulator material

A dual free layer (DFL) read head or reader oftentimes has a sidebump in a signal amplitude vs. cross-track profile plot. The sidebump is a magnetic signal of the reader in response to the magnetic field of magnetic media with finite thickness. The sidebump magnitude is far below the main magnetic signal of the reader and is offset from the center of the track in the cross-track direction. When two sidebumps are present (one on each side of the center of the track), the sidebump should generally and ideally be symmetrically offset in the cross-track direction else there is a negative impact on reader performance. To obtain offset symmetry, a synthetic antiferromagnetic (SAF) shield may be used, magnetic moments of soft bias layers can be adjusted, and spacing between the free layers of the DFL read head and the layers of the soft bias can also be adjusted.

DFL reader signal sidebump imbalance reduction

The present disclosure generally relates to a magnetic recording head comprising one or more spin-orbit torque (SOT) devices, the SOT devices each comprising a bismuth antimony (BiSb) layer. The magnetic recording head comprises a SOT device comprising a first shield extending to a media facing surface (MFS), a seed layer disposed over the first shield, the seed layer being disposed at the MFS, a free layer disposed on the seed layer, the free layer being disposed at the MFS, a bismuth antimony (BiSb) layer disposed over the free layer, the BiSb layer being recessed from the MFS, a second shield disposed over the BiSb layer, the second shield extending to the MFS, and a shield notch coupled to the second shield, the shield notch being disposed between the first shield and the second shield. The magnetic recording head may be a two-dimensional magnetic recording head comprising two SOT devices.

Spin-orbit torque SOT reader with recessed spin hall effect layer

An apparatus is provided that includes an array including n rows and m columns of nodes, each row of nodes coupled to one of n first conductive lines, each column of nodes coupled to one of m second conductive lines, each node of the n rows and m columns of nodes including a spin orbit torque MRAM non-volatile memory cell configured to store a corresponding weight of an n×m array of weights each having a first weight value or a second weight value, and a control circuit configured to apply n input voltages each having a first input value or a second input value to corresponding n first conductive lines, the n input voltages corresponding to an n-element input vector. The spin orbit torque MRAM non-volatile memory cells are configured to generate m output currents at the m second conductive lines upon application of the n input voltages. The m output currents corresponding to a result of multiplying the input vector by the n×m array of weights.

Matrix-vector multiplication using SOT-based non-volatile memory cells

Computing devices, such as mobile computing devices, have access to one or more image sensors that can capture images and video with multiple subjects. Some of these subjects may vary in priority for various tasks. It may be desired to increase or decrease the compression on each subject in order to more efficiently store the image data. Low-power, fast-response machine learning logic can be configured to allow for the generation of a plurality of inference data. Inference data can be associated with the type, motion and/or priority of the subjects as desired. This inference data can be utilized along with other subject data to generate one or more variable compression regions within the image data. The image data can be subsequently processed to compress different areas of the image based on a desired application. The variably compressed image can reduce file sizes and allow for more efficient storage and processing.

Low-power fast-response machine learning variable image compression

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 a magnetic recording head comprising a spintronic device for magnetic media, such as a magnetic media drive. The spintronic device includes at least one spin Hall layer as well as at least one buffer layer and at least one interlayer. The buffer layer is positioned proximate a main pole of a write head while the interlayer is positioned proximate a trailing shield of the write head. The spin Hall layer is positioned between the buffer layer and the interlayer. The spintronic element may be disposed at the media facing surface (MFS) or recessed from the MFS. The spintronic device is capable of injecting spin current to the main pole, the trailing shield, or both.

Spin-orbit torque (SOT) writer with topological insulator materials

Growing community of inventors

San Jose, CA, United States of America

Xiaoyong Liu