Eastman-kodak Company

Hitachi Global Storage Technologies Netherlands B.v.

Hgst Netherlands, B.v.

Western Digital Technologies, Inc.

Sandisk Technologies Inc.

International Business Machines Corporation

Neil Smith

Jeffrey Childress

Bruce Alvin Gurney

Frederick J Jeffers

Matthew Joseph Carey

Jordan Asher Katine

Stefan Maat

Patrick Braganca

Goran Mihajlovic

Neil Leslie Robertson

Yang Li

Thomas Dudley Boone, Jr

Quang Le

Ernesto Esteban Marinero

James Lamar Nix

Jay D Freeman

Robert Fontana

Richard Leo Galbraith

Bruce Alexander Wilson

Yimin Hsu

Petrus Antonius Van Der Heijden

Rehan Ahmed Zakai

Mason Lamar Williams

Peter VanderSalm Koeppe

Kent R Gandola

Daniele Mauri

David John Seagle

Hugo Alberto Emilio Santini

Howard Gordon Zolla

Douglas Johnson Werner

Robert O James

Elizabeth Ann Dobisz

Bhagwati Prasad

Alan Kalitsov

John C Read

Young-Suk Choi

Liesl Folks

Tiffany Santos

Petrus Antonius VanDerHeijden

Bradford D West

Petrus Antonius Vanderheijden

Hardayal Singh Gill

Bo Yang

Jeffrey Scott Lille

Tsann Lin

Aron Pentek

Brian Rodrick York

Kurt A Rubin

Michael Grobis

Alexander Michael Zeltser

Ronald Myron Wexler

Sharat Batra

Hamid Balamane

Yoshihiro Ikeda

Nian Xiang Sun

Kentaro Takano

Frederick Rockwell Chamberlain, Iv

Charles F Brucker

Christopher Dana Keener

Walter Eugene Weresin

Hsin-Wei Tseng

Steven J Adamson

Tomasz Mark Jagielinski

Michael Tran

Frederick R Chamberlain

Greg A Burg

Hin Pong Edward Lee

John R Shelor

A spin-transfer torque (STT) magnetoresistive memory device includes a first electrode, a second electrode, and a magnetic tunnel junction located between the first electrode and the second electrode. The magnetic tunnel junction includes a reference layer having a fixed magnetization direction, a free layer stack, and a nonmagnetic tunnel barrier layer located between the reference layer and the free layer stack. The free layer stack has a total thickness of less than 2 nm, and contains in order, a proximal ferromagnetic layer located proximal to the nonmagnetic tunnel barrier layer, a first non-magnetic metal sub-monolayer, an intermediate ferromagnetic layer, a second non-magnetic metal sub-monolayer, and a distal ferromagnetic layer.

Spin-transfer torque magnetoresistive memory device with a free layer stack including multiple spacers and methods of making the same

A magnetic memory device includes a first electrode, a second electrode, and a layer stack located between the first electrode and the second electrode. The layer stack includes a reference layer, a tunnel barrier layer, a free layer, and a magnetoelectric multiferroic layer including at least one crystalline grain. The magnetization of the magnetoelectric multiferroic layer may be axial, canted, or in-plane. For axial or canted magnetization of the magnetoelectric multiferroic layer, a deterministic switching of the free layer may be achieved through coupling with the axial component of magnetization of the magnetoelectric multiferroic layer. Alternatively, the in-plane magnetization of the magnetoelectric multiferroic layer may be employed to induce precession of the magnetization angle of the free layer.

Multiferroic-assisted voltage controlled magnetic anisotropy memory device and methods of manufacturing the same

A spin-transfer torque (STT) magnetoresistive memory device includes a first electrode, a second electrode, and a magnetic tunnel junction located between the first electrode and the second electrode. The magnetic tunnel junpction includes a reference layer having a fixed magnetization direction, a free layer stack, and a nonmagnetic tunnel barrier layer located between the reference layer and the free layer stack. The free layer stack has a total thickness of less than 2 nm, and contains in order, a proximal ferromagnetic layer located proximal to the nonmagnetic tunnel barrier layer, a first non-magnetic metal sub-monolayer, an intermediate ferromagnetic layer, a second non-magnetic metal sub-monolayer, and a distal ferromagnetic layer.

A magnetoresistive random access memory (MRAM) memory cell comprises a pinned layer having fixed direction of magnetization that is perpendicular to a plane of the pinned layer, a first free layer having a direction of magnetization that can be switched and is perpendicular to a plane of the first free layer, a tunnel barrier positioned between the pinned layer and the first free layer, a second free layer having a direction of magnetization that can be switched, and a spacer layer positioned between the first free layer and the second free layer. Temperature dependence of coercivity of the second free layer is greater than temperature dependence of coercivity of the first free layer.

Heat assisted perpendicular spin transfer torque MRAM memory cell

The present disclosure generally relates to a SOT-MRAM cell that has a spin Hall effect layer and a magnetic tunnel junction. The magnetic tunnel junction is disposed at an edge of the spin Hall effect layer. In order to write the cell, current is applied through the spin Hall effect layer to create spin accumulation of z-polarized spins under the free layer due to the spin Hall effect. The spins exert a spin torque on the free layer via spin diffusion. Based upon the design, the SOT-MRAM cell has deterministic switching of the perpendicular free layer with the spin Hall effect layer without application of an external magnetic field.

SOT MRAM cell with perpendicular free layer and its cross-point array realization

A method and apparatus for deterministically switching a free layer in a spin orbit torque magnetoresistive random access memory (SOT-MRAM) cell is disclosed herein. In one embodiment, an SOT-MRAM memory cell is provided. The SOT-MRAM memory cell includes a magnetic tunnel junction, a ferromagnetic bias layer, and an antiferromagnetic layer. The magnetic tunnel junction includes a free layer having primarily two bi-stable magnetization directions, a reference layer having a fixed magnetization direction, and an insulating tunnel barrier layer positioned between the free layer and the reference layer. The ferromagnetic bias layer is configured to provide spin orbit torque via anomalous Hall effect and simultaneously configured to provide a magnetic bias field on the free layer to achieve deterministic switching. The antiferromagnetic layer is positioned below the ferromagnetic bias layer and is configured to pin a magnetization direction of the ferromagnetic bias layer in a predetermined direction.

Three terminal SOT memory cell with anomalous hall effect

A spin orbit torque magnetoresistive random access memory (SOT MRAM) cell includes a magnetic tunnel junction that contains a free layer having two bi-stable magnetization directions, a reference magnetic layer having a fixed magnetization direction, and a tunnel barrier layer located between the free layer and the reference layer, and a nonmagnetic spin Hall effect layer. The spin Hall effect layer may include an alternating stack of beta phase tungsten layers and noble metal nonmagnetic dusting layers. Alternatively or in addition, a hafnium layer may be located between the nonmagnetic spin Hall effect layer and the free layer.

Spin orbit torque magnetoresistive random access memory containing composite spin hall effect layer including beta phase tungsten

An MRAM memory cell is proposed that is based on spin accumulation torque. One embodiment includes a magnetic tunnel junction, a spin accumulation layer connected to the magnetic tunnel junction and a polarization layer connected to the spin accumulation layer. The polarization layer and the spin accumulation layer use spin accumulation to provide a spin accumulation torque on the free magnetic layer of the magnetic tunnel junction to change direction of magnetization of the free magnetic layer.

Spin accumulation torque MRAM

Apparatuses, systems, and methods are disclosed for magnetoresistive random access memory. A plurality of read lines are in a read line layer, and a plurality of write lines are in a write line layer. A plurality of spin accumulation lines are in a spin accumulation line layer disposed between a read line layer and a write line layer. Spin accumulation lines may horizontally cross read lines and write lines. A plurality of vertical magnetoresistive random access memory (MRAM) cells may include polarizers and magnetic tunnel junctions. A vertical MRAM cell may include a polarizer coupled between a spin accumulation line and a write line. A vertical MRAM cell may further include a magnetic tunnel junction coupled between a spin accumulation line and a read line, such that the magnetic tunnel junction and the polarizer are vertically aligned.

Cross-point spin accumulation torque MRAM

Three terminal SOT memory cell with anomalous Hall effect

The embodiments of the present invention relate to a method for forming a magnetic read head having side by side sensors. The method includes depositing a pinned layer, a barrier layer and a free layer over a shield, and removing portions of the pinned layer, barrier layer and free layer to expose portions of the shield. A bias material is deposited over the exposed shield. An opening is formed in the free layer to expose the barrier layer, and an insulative material is deposited into the opening. The resulting side by side sensors each has its own free layer separated by the insulative nonmagnetic material. The side by side sensors share the pinned layer.

Fabrication of side-by-side sensors for MIMO recording

A system, according to one embodiment, includes a magnetic head having sensor structures disposed laterally along a cross-track direction, each sensor structure having a free layer, a soft bias layer positioned laterally to each sensor structure, an antiparallel coupling layer above each soft bias layer, a magnetic layer above each antiparallel coupling layer, wherein magnetic moments of the soft bias layer and the magnetic layer are antiparallel coupled, and a stabilizing layer above each magnetic layer for stabilizing a magnetic orientation of the magnetic layer. Moreover, opposing faces of the magnetic layers are positioned apart by a distance that causes each magnetic layer to form a magnetic circuit with the associated free layer and the associated soft bias layer.

MIMO read head with soft bias and split shield

A system comprising a sensor with a free layer that exhibits an anomalous Hall effect is disclosed. Further, the sensor has a magnetic underlayer below the free layer in a track direction for biasing a magnetic orientation of the free layer in a first magnetic orientation, and a magnetic overlayer above the free layer in the track direction for biasing the magnetic orientation of the free layer in the first magnetic orientation. Still further, the sensor has a lower nonmagnetic spacer layer between the magnetic underlayer and the free layer, and an upper nonmagnetic spacer layer between the magnetic overlayer and the free layer.

Magnetic stabilization and scissor design for anomalous hall effect magnetic read sensor

A method for making a current-perpendicular-to-the-plane magnetoresistive sensor structure produces a top electrode that is 'self-aligned' on the top of the sensor and with a width less than the sensor trackwidth. A pair of walls of ion-milling resistant material are fabricated to a predetermined height above the biasing layers at the sensor side edges. A layer of electrode material is then deposited onto the top of the sensor between the two walls. The walls serve as a mask during angled ion milling to remove outer portions of the electrode layer. The height of the walls and the angle of ion milling determines the width of the resulting top electrode. This leaves the reduced-width top electrode located on the sensor. Because of the directional ion milling using walls that are aligned with the sensor side edges, the reduced-width top electrode is self-aligned in the center of the sensor.

Method for making a current-perpendicular-to-the-plane (CPP) magnetoresistive (MR) sensor with reduced-width self-aligned top electrode

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San Jose, CA, United States of America

Neil Smith