Headway Technologies, Incorporated

International Business Machines Corporation

Hgst Netherlands, B.v.

Maglabs, Inc.

Hitachi Global Storage Technologies Netherlands B.v.

Meglabs, Inc.

Kochan Ju

Simon H Liao

Cheng Tzong Horng

Jei-Wei Chang

Min Li

Mao-Min Chen

Youfeng Zheng

Cherng-Chyi Han

Po-Kang Wang

Ru-Ying Tong

You Feng Zheng

Yimin Guo

Bernard Dieny

Xuehua Wu

Jeiwei Chang

Hui-Chuan Wang

Masashi Sano

Kunliang Zhang

Chyu-Jiuh Torng

Mohamad Towfik Krounbi

Ching Hwa Tsang

Hung Liang Hu

Yi-Chun Liu

Koichi Terunuma

Lijie Guan

Neil Leslie Robertson

Yun-Fei Li

Cherng Chyi Han

Kiyoshi Noguchi

Quang Le

Rongfu Xiao

Guangli Liu

Chao-Peng Chen

Ru Ying Tong

Yaw Shing Tang

Charles C Lin

Ben Hu

You Fong Zheng

Chun Liu

Zheng Gao

Yimin Hsu

Yue Liu

Xizeng Shi

Ying Hong

Hugo Alberto Santini

Chen-Jung Chien

Kevin K Lin

Chyu Jiuh Torng

Rodney E Lee

Yining Hu

Henry C Chang

Chunping Luo

Stuart Kao

Chien-Li Lin

Charles H Lin

Shou-Chen Kao

Chao Chen

Si-Tuan Lam

Wensen Li

Xue Hua Wu

Oletta Allegranza

Kuok San Ho

James Mac Freitag

Tsann Lin

Otto Voegeli

Denny D Tang

Sangmun Oh

Ian L Sanders

Rod Lee

Jei Wei Chang

Heinrich Sussner

Timothy J Gallagher

Richard George Hirko

Arthur Hungshin Tao

Rachid Sbiaa

Ku-Ying Tong

Liji Guan

Julie Chen

A magnetic tunnel junction (MTJ) for use in a magnetoresistive random access memory (MRAM) has a CoFeB alloy free layer located between the MgO tunnel barrier layer and an upper MgO capping layer, and a CoFeB alloy enhancement layer between the MgO capping layer and a Ta cap. The CoFeB alloy free layer has high Fe content to induce perpendicular magnetic anisotropy (PMA) at the interfaces with the MgO layers. To avoid creating unnecessary PMA in the enhancement layer due to its interface with the MgO capping layer, the enhancement layer has low Fe content. After all of the layers have been deposited on the substrate, the structure is annealed to crystallize the MgO. The CoFeB alloy enhancement layer inhibits diffusion of Ta from the Ta cap layer into the MgO capping layer and creates good crystallinity of the MgO by providing CoFeB at the MgO interface.

Perpendicular spin transfer torque (STT) memory cell with double MgO interface and CoFeB layer for enhancement of perpendicular magnetic anisotropy

A magnetic sensor having a novel pinning structure resulting in a greatly reduced gap spacing. The sensor has a magnetic free layer structure that extends to a first stripe height and a magnetic pinned layer structure that extends to a second stripe height that is longer than the first stripe high. A layer of anti-ferromagnetic material is formed over the pinned layer structure in the region beyond the first stripe height location. In this way, the antiferromagnetic layer is between the pinned layer and the second or upper shield and does not contribute to gap spacing.

Magnetic sensor having an extended pinned layer with stitched antiferromagnetic pinning layer

The embodiments disclosed generally relate to a read head in a magnetic recording head. The read head utilizes a sensor structure having: a pinned magnetic structure recessed from a media facing surface; and a reader gap structure. The reader gap structure has a spacer layer recessed from the media facing surface and disposed on top of the pinned magnetic structure, a recessed first free layer partially recessed from the media facing surface and disposed on top of the barrier layer, a second free layer extending to the media facing surface an disposed on top of the barrier layer, and a cap layer extending to the media facing surface disposed atop the second free layer. The pinned magnetic structure, the spacer, and the first free layer have a common face which is on an angle relative to the media facing surface.

TMR/CPP reader for narrow reader gap application

A magnetic read head that has improved pinned layer stability while also maintaining excellent free layer stability. The free layer has sides that define a trackwidth of the sensor and a back edge that defines a functional stripe height of the sensor. However, the pinned layer can extend significantly beyond both the width of the free layer and the back edge (e.g. stripe height) of the free layer. The sensor also has a soft magnetic bias structure that compensates for the reduced volume presented by the side extension of the pinned layer. The soft magnetic bias structure can be magnetically coupled with the trailing magnetic shield, either parallel coupled or anti-parallel coupled. In addition, all or a portion of the soft magnetic bias structure can be exchange coupled to a layer of anti-ferromagnetic material in order to improve the robustness of the soft magnetic bias structure.

Magnetic sensor with extended pinned layer and partial wrap around shield

A magnetic read sensor having an extended pinned layer structure and also having an extended free layer structure. The extended pinned layer structure and extended free layer structure both extend beyond the strip height of the free layer of the sensor to provide improved pinning strength as well as improved free layer biasing reliability and bias field strength.

Magnetic sensor having an extended pinned layer and shape enhanced bias structure

A transducer according to one embodiment comprises a first ferromagnetic layer; a second ferromagnetic layer; and an electrically conductive layer positioned between the ferromagnetic layers; wherein a length of the first ferromagnetic layer in a first direction parallel to a plane of deposition thereof is greater than a length of the electrically conductive layer in the first direction such that a first end of the first ferromagnetic layer extends beyond an end of the electrically conductive layer in the first direction, wherein an electrical current enters or exits the end of the first ferromagnetic layer that extends beyond the end of the electrically conductive layer in the first direction. Additional transducer structures, and systems implementing such transducers, are also disclosed.

Read transducer and magnetic storage system implementing same

A magnetic structure in one embodiment includes a tunnel barrier layer; a free layer; and a buffer layer between the tunnel barrier layer and the free layer, wherein a cross sectional area of the tunnel barrier layer in a direction parallel to a plane of deposition thereof is greater than a cross sectional area of the free layer in a direction parallel to a plane of deposition thereof, wherein a cross sectional area of the buffer layer in a direction parallel to a plane of deposition thereof is greater than a cross sectional area of the free layer in the direction parallel to the plane of deposition thereof. Additional systems and methods are also presented.

Low resistance tunnel magnetoresistance (TMR) structure

The series resistance of a CPP GMR stack can be reduced by shaping it into a small upper, on a somewhat larger, lower part. Because of the sub-micron dimensions involved, good alignment between these is normally difficult to achieve. The present invention discloses a self-alignment process based on first laying down a mask that will determine the shape of the top part. Ion beam etching is then initiated, the ion beam being initially applied from one side only at an angle to the surface normal. During etching, all material on the near side of the mask gets etched but, on the far side, only material that is outside the mask's shadow gets removed so, depending on the beam's angle, the size of the lower part is controlled and the upper part is precisely centrally aligned above it.

CPP head with parasitic shunting reduction

The problem of increased edge sensitivity associated with the reduction of the spacing between bias magnets in a CPP head has been solved by limiting the width of the bias cancellation layer and by adding an extra layer of insulation to ensure that current through the device flows only through its central area, thereby minimizing its edge reading sensitivity.

Narrow track CPP head with bias cancellation

Process to manufacture narrow track CPP head with bias cancellation

It has been found that the insertion of a copper laminate within CoFe, or a CoFe/NiFe composite, leads to higher values of CPP GMR and DRA. However, this type of structure exhibits very negative magnetostriction, in the range of high &#x2212;10to &#x2212;10. This problem has been overcome by giving the copper laminates an oxygen exposure treatment When this is done, the free layer is found to have a very low positive magnetostriction constant. Additionally, the value of the magnetostriction constant can be adjusted by varying the thickness of the free layer and/or the position and number of the oxygen treated copper laminates.

GMR device having an improved free layer

A 'toggling' type of magnetic random access memory (MRAM) has memory stacks arranged in the X-Y plane on the MRAM substrate with each memory stack having a plurality of toggle memory cells stacked along the Z axis. Each stack is located at an intersection region between the two orthogonal write lines. The cells are stacked in pairs, with the cells in each pair having their easy axes of magnetization aligned substantially parallel to one another and nonparallel with the X and Y axes. The cells in each pair have their free layers magnetically biased in opposite directions. Because the free layer of each cell in a pair is biased in a direction opposite to the bias direction of the free layer of the other cell, one cell in a pair can be toggle written without toggle writing the other cell in the pair. The bias fields on the free layers reduces the required switching field for each cell, which results in less write current and a lower-power toggling MRAM.

Magnetic random access memory with stacked toggle memory cells having oppositely-directed easy-axis biasing

Single write poles tend to large shape anisotropy which results in a very large remnant field when not actually writing. This has now been eliminated by giving the write pole the form of a three layer laminate in which two ferromagnetic layers are separated by a non-magnetic or antiferromagnetic coupling layer. Strong magnetostatic coupling between the outer layers causes their magnetization directions to automatically be antiparallel to one another, unless overcome by the more powerful write field, leaving the structure with a low net magnetic moment. The thickness of the middle layer must be carefully controlled.

Thin laminated single pole perpendicular write head

Patterned, longitudinally and transversely antiferromagnetically exchange biased GMR sensors are provided which have narrow effective trackwidths and reduced side reading. The exchange biasing significantly reduces signals produced by the portion of the ferromagnetic free layer that is underneath the conducting leads while still providing a strong pinning field to maintain sensor stability. In the case of the transversely biased sensor, the magnetization of the free and biasing layers in the same direction as the pinned layer simplifies the fabrication process and permits the formation of thinner leads by eliminating the necessity for current shunting.

Patterned, synthetic longitudinally exchange biased GMR sensor

In a single vertical pole magnetic writer, flux passing through the return pole can sometimes be strong enough to erase previously recorded data. This problem has been overcome by the addition of a second return pole that is magnetically connected to the conventional return pole for the purpose of collecting leaked flux, thereby preventing it from reaching the underlayer.

Return pole field reduction for perpendicular write head

Growing community of inventors

Monte Sereno, CA, United States of America

Kochan Ju