Seagate Technology Incorporated

Western Digital (fremont), Inc.

Western Digital Technologies, Inc.

Sandisk Technologies Inc.

Yuankai Zheng

Haiwen Xi

Dimitar Velikov Dimitrov

Qunwen Leng

Christian Kaiser

Zheng Gao

Ming Mao

Zhitao Diao

Dexin Wang

Xiaobin Wang

Xiaohua Lou

Wei Tian

Chih-Ching Hu

Chen-jung Chien

Wenzhong Zhu

Daniele Mauri

Yung-Hung Wang

Ming Jiang

Shaoping Li

Gerardo Bertero

Yong Lu

James Mac Freitag

Yiran Chen

Cheng-Han Yang

Mahendra Pakala

Wonjoon Jung

Shihai He

Rongfu Xiao

Michael Xuefei Tang

Ronghui Zhou

Xin Jiang

Xuebing Feng

Kaizhong Gao

Yimin Guo

Hai Li

Brian Rodrick York

Hongyue Liu

Olle Gunnar Heinonen

Susumu Okamura

Dujiang Wan

Anup Roy

Zhihong Zhang

Lei Wang

Michael L Mallary

Tong Zhao

Harry Hongyue Liu

Yunfei Ding

Brian Lee

Laurence Lujun Chen

Carlos Corona

Ling Wang

Pat J Ryan

Miaoyin Wang

Daniel K Lottis

Joshua Jones

Chen Jung Chien

Abhinandan Chougule

Petrus Antonius Van Der Heijden

Patrick Joseph Ryan

Alexander Goncharov

Alexander Michael Zeltser

Matthew A Stevenson

Zhipeng Li

Goncalo Baiao De Albuquerque

Jianxin Fang

Wei Tan

Chen-Jung Chen

Ann Lorraine Carvajal

The present disclosure generally relates to a two-dimensional magnetic recording (TDMR) read head. The TDMR read head comprises a first sensor, a second sensor, and a middle shield (MS) disposed between the first and second sensors. The MS comprises a seed layer, an IrMn layer disposed on the seed layer, an insertion layer comprising Ru or CoFe disposed on the IrMn layer, a first NiFe layer having a pinned magnetization, and a cap layer disposed over the first NiFe layer. In one embodiment, the MS further comprises an Ru layer disposed on the first NiFe layer and a second NiFe layer disposed on the Ru layer, the second NiFe layer having a pinned magnetization in a direction antiparallel to the first NiFe layer. The insertion layer comprising Ru decreases an exchange energy of the MS. The insertion layer comprising CoFe increases an exchange energy of the MS.

Pinned shield with controllable exchange bias field

The present disclosure generally relates to magnetoresistive (MR) devices. The MR device comprises a synthetic antiferromagnetic (SAF) layer that increases exchange coupling field, and in turn, less magnetic noise of such devices. The MR device comprises a first ferromagnetic (FM1) layer and a second ferromagnetic (FM2) layer, in between which is an SAF spacer of RuAl alloy having a B2 crystalline structure which may grow epitaxial on BCC (110) or FCC (111) textures, meaning that the (110) or (111) plane is parallel to the surface of MR device substrate. Further, amorphous layers may be inserted into the device structure to reset the growth texture of the device to a (001), (110), or (111) texture in order to promote the growth of tunneling barrier layers or antiferromagnetic (AF) pinning layers.

Magnetoresistive devices comprising a synthetic antiferromagnetic coupling layer of RuAl having a (110) texture

Embodiments of the present disclosure generally relate to a read sensor utilized in a read head. The read sensor comprises an amorphous break layer disposed on a shield, a seed layer disposed on the amorphous break layer, a first ferromagnetic layer disposed on the seed layer, a barrier layer disposed on the first ferromagnetic layer, and a second ferromagnetic layer disposed on the barrier layer. The amorphous break layer comprises CoFeBTa, the seed layer comprises RuAl, and the barrier layer comprises a semiconductor material, such as ZnSe, ZnTe, ZnO, CuSe, or CuInGaSe. The semiconductor barrier layer reduces the resistance-area product of the read sensor. The amorphous break layer breaks the texture between the shield, which has a FCC texture, and the seed layer, which has a BCC texture. The BCC texture of the seed layer is then inherited by the remaining layers disposed over the seed layer.

Read sensor with ordered heusler alloy free layer and semiconductor barrier layer

The present disclosure generally relates to magnetoresistive (MR) devices. The MR device comprises a synthetic antiferromagnetic (SAF) layer that increases stability to magnetic fields, and in turn, results in lower magnetic noise of the device. The MR device comprises a first ferromagnetic (FM1) layer and a second ferromagnetic (FM2) layer, in between which is an SAF spacer of RuAl alloy having a B2 crystalline structure with (001) texture, meaning that the (001) plane is parallel to the surface of MR device substrate. The first ferromagnetic (FM1) layer and a part of the second ferromagnetic (FM2) layer also have the (001) texture. An amorphous layer in a second ferromagnetic (FM2) layer can reset the growth texture of the MR device to a (111) texture in order to promote the growth of an antiferromagnetic (AF) pinning layer.

Magnetoresistive device comprising a synthetic antiferromagnetic coupling layer of RuAl having a (001) texture

A magnetic element includes a first free layer, a barrier layer over the first free layer, and a second free layer over the barrier layer. The first free layer includes a first ferromagnetic bilayer and a first amorphous insertion layer (e.g., CoHf) between the first ferromagnetic bilayer. The first ferromagnetic bilayer is selected from CoB, CoFeB, FeB, and combinations thereof. The second free layer includes a second ferromagnetic bilayer and a second amorphous insertion layer (e.g., CoHf) between the second ferromagnetic bilayer. The second ferromagnetic bilayer is selected from CoB, CoFeB, FeB, and combinations thereof. Each of the first and the second amorphous insertion layer independently can be ferromagnetic or non-ferromagnetic and can have a recrystallization temperature of about 300&#xb0; C. and above. The magnetic element can further include a non-ferromagnetic amorphous buffer layer and/or a non-ferromagnetic amorphous capping layer. The magnetic element can further include a ferromagnetic amorphous seed layer.

Magnetic elements of amorphous based dual free layer structures and recording devices using such elements

The present disclosure generally relates to a Wheatstone bridge array that has four resistors. Each resistor includes a plurality of TMR structures. Two resistors have identical TMR structures. The remaining two resistors also have identical TMR structures, though the TMR structures are different from the other two resistors. Additionally, the two resistors that have identical TMR structures have a different resistance area as compared to the remaining two resistors that have identical TMR structures. Therefore, the working bias field for the Wheatstone bridge array is non-zero.

Magnetic sensor array with different RA TMR film

The present disclosure generally relates to a Wheatstone bridge array that has four resistors. Each resistor includes a plurality of TMR films. Each resistor has identical TMR films. The TMR films of two resistors have reference layers that have an antiparallel magnetic orientation relative to the TMR films of the other two resistors. To ensure the antiparallel magnetic orientation, the TMR films are all formed simultaneously and annealed in a magnetic field simultaneously. Thereafter, the TMR films of two resistors are annealed a second time in a magnetic field while the TMR films of the other two resistors are not annealed a second time.

Magnetic sensor array with single TMR film plus laser annealing and characterization

A tunneling magnetoresistance (TMR) sensor device is disclosed that includes four or more TMR resistors. The TMR sensor device comprises a first TMR resistor comprising a first TMR film, a second TMR resistor comprising a second TMR film different than the first TMR film, a third TMR resistor comprising the second TMR film, and a fourth TMR resistor comprising the first TMR film. The first, second, third, and fourth TMR resistors are disposed in the same plane. The first TMR film comprises a synthetic anti-ferromagnetic pinned layer having a magnetization direction of the reference layer orthogonal to a free layer. The second TMR film comprises a double synthetic anti-ferromagnetic pinned layer having a magnetization direction of the reference layer orthogonal to the magnetization of a free layer, but opposite to the magnetization direction of the reference layer of the first TMR film.

Magnetic sensor with dual TMR films and the method of making the same

The present disclosure generally relates to a Wheatstone bridge array comprising TMR sensors and a method of fabrication thereof. In the Wheatstone bridge array, there are four distinct TMR sensors. The TMR sensors are all fabricated simultaneously to create four identical TMR sensors that have synthetic antiferromagnetic free layers as the top layer. The synthetic antiferromagnetic free layers comprise a first magnetic layer, a spacer layer, and a second magnetic layer. After forming the four identical TMR sensors, the spacer layer and the second magnetic layer are removed from two TMR sensors. Following the removal of the spacer layer and the second magnetic layer, a new magnetic layer is formed on the now exposed first magnetic layer such that the new magnetic layer has substantially the same thickness as the spacer layer and second magnetic layer combined.

Magnetic sensor array with one TMR stack having two free layers

A tunneling magnetoresistance (TMR) sensor device is disclosed that includes one or more TMR sensors. The TMR sensor device comprises a first resistor comprising a first TMR film, a second resistor comprising a second TMR film different than the first TMR film, a third resistor comprising the second TMR film, and a fourth resistor comprising the first TMR film. The first TMR film comprises a reference layer having a first magnetization direction anti-parallel to a second magnetization direction of a pinned layer. The second TMR film comprises a reference layer having a first magnetization direction parallel to a second magnetization direction of a first pinned layer, and a second pinned layer having a third magnetization direction anti-parallel to the first magnetization direction of the reference layer and the second magnetization direction of the first pinned layer.

Magnetic sensor array with dual TMR film

Embodiments of the present disclosure generally relate to a sensor of magnetic tunnel junctions (MTJs) with shape anisotropy. In one embodiment, a tunnel magnetoresistive (TMR) based magnetic sensor in a Wheatstone configuration includes at least one magnetic tunnel junctions (MTJ). The MTJ includes a free layer having a first edge and a second edge. The free layer has a thickness of about 100 &#x212b; or more. The free layer has a width and a height with a width-to-height aspect ratio of about 4:1 or more. The MTJ has a first hard bias element positioned proximate the first edge of the free layer and a second hard bias element positioned proximate the second edge of the free layer.

TMR sensor with magnetic tunnel junctions with shape anisotropy

A spin torque oscillator includes a first electrode, a second electrode and a device layer stack located between the first electrode and the second electrode. The device layer stack includes a spin polarization layer including a first ferromagnetic material, an assist layer including a third ferromagnetic material, a ferromagnetic oscillation layer including a second ferromagnetic material located between the spin polarization layer and the assist layer, a nonmagnetic spacer layer located between the spin polarization layer and the ferromagnetic oscillation, and a nonmagnetic coupling layer located between the ferromagnetic oscillation layer and the assist layer. The assist layer is antiferromagnetically coupled to the ferromagnetic oscillation layer through the non-magnetic coupling layer, and the assist layer has a magnetization that is coupled to a magnetization of the ferromagnetic oscillation layer.

Spin torque oscillator with an antiferromagnetically coupled assist layer and methods of operating the same

A method of fabricating a TMR based magnetic sensor in a Wheatstone configuration includes conducting a first anneal of a magnetic tunnel junction (MTJ) and conducting a second anneal of the MTJ. The MTJ includes a first antiferromagnetic (AFM) pinning layer, a pinned layer over the first AFM pinning layer, an anti-parallel coupled layer over the pinned layer, a reference layer over the anti-parallel coupled layer, a barrier layer over the reference layer, a free layer over the barrier layer, and a second antiferromagnetic pinning layer over the free layer. The first anneal of the MTJ sets the first AFM pinning layer, the pinned layer, the free layer, and the second AFM pinning layer in a first magnetization direction. The second anneal of the MTJ resets the free layer and the second AFM pinning layer in a second magnetization direction. An operating field range of the TMR based magnetic sensor is over &#xb1;100 Oe.

Large field range TMR sensor using free layer exchange pinning

Embodiments of the present disclosure generally relate to a write head for a magnetic recording device. The write head includes a spin torque oscillator (STO) that has a seed layer formed on a write pole, a spin polarization layer (SPL) formed on the seed layer, a first spacer layer formed on the SPL, a field generation layer (FGL) formed on the first spacer layer, a second spacer layer formed on the FGL, and a notch formed on the second spacer layer. The FGL and the notch are antiferromagnetically coupled through the second spacer layer and thus increases the FGL angle and improves the write capabilities of the write head.

MAMR head with synthetic antiferromagnetic (SAF) coupled notch

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Fremont, CA, United States of America

Yuankai Zheng