Everspin Technologies, Inc.

Freescale Semiconductor,inc.

Jijun Sun

Jon Michael Slaughter

Renu Whig

Nicholas David Rizzo

Frederick B Mancoff

Sanjeev Aggarwal

Dimitri Houssameddine

Renu Whig Dave

Han-Jong Chia

Srinivas V Pietambaram

Jason A Janesky

Phillip G Mather

Bradley Neal Engel

Sumio Ikegawa

Thomas Andre

Syed M Alam

Sarin A Deshpande

Chaitanya Mudivarthi

Han Kyu Lee

Kevin M Conley

Kerry Joseph Nagel

Shimon

Wenchin Lin

John T Martin

Johan Akerman

Lu Hui

Ahmet Demiray

John Slaughter

A magnetoresistive element (e.g., a spin-torque magnetoresistive memory element) includes a fixed magnetic layer, a free magnetic layer, having a high-iron alloy interface region located along a surface of the free magnetic layer, wherein the high-iron alloy interface region has at least 50% iron by atomic composition, and a first dielectric, disposed between the fixed magnetic layer and the free magnetic layer. The magnetoresistive element further includes a second dielectric, having a first surface that is in contact with the surface of the free magnetic layer, and an electrode, disposed between the second dielectric and a conductor. The electrode includes: (i) a non-ferromagnetic portion having a surface that is in contact with a second surface of the second dielectric, and (ii) a second portion having at least one ferromagnetic material disposed between the non-ferromagnetic portion of the electrode and the conductor.

Magnetoresistive stack and method of fabricating same

The present disclosure is drawn to, among other things, a magnetoresistive device and a magnetoresistive memory comprising a plurality of such magnetoresistive devices. In some aspects, a magnetoresistive device may include a magnetically fixed region, a magnetically free region above or below the magnetically fixed region, and an intermediate region positioned between the magnetically fixed region and the magnetically free region, wherein the intermediate region includes a first dielectric material. The magnetoresistive device may also include encapsulation layers formed on opposing side walls of the magnetically free region, wherein the encapsulation layers include the first dielectric material.

Magnetoresistive stack/structure and methods therefor

A method of fabricating a magnetoresistive device includes forming a magnetically fixed region on one side of an intermediate region. Forming the magnetically fixed region may include forming a first ferromagnetic region and forming an antiferromagnetic coupling region on one side of the first ferromagnetic region. The method may also include treating a surface of the coupling region by exposing the surface to a gas, and forming a second ferromagnetic region on the treated surface of the coupling region.

A magnetoresistive stack/structure and method of manufacturing same comprising wherein the stack/structure includes a seed region, a fixed magnetic region disposed on and in contact with the seed region, a dielectric layer(s) disposed on the fixed magnetic region and a free magnetic region disposed on the dielectric layer(s). In one embodiment, the seed region comprises an alloy including nickel and chromium having (i) a thickness greater than or equal to 40 Angstroms (+/−10%) and less than or equal to 60 Angstroms (+/−10%), and (ii) a material composition or content of chromium within a range of 25-60 atomic percent (+/−10%) or 30-50 atomic percent (+/−10%).

Magnetoresistive stack with seed region and method of manufacturing the same

A magnetoresistive stack may include: a fixed region having a fixed magnetic state, a spacer region, a first dielectric layer and a second dielectric layer, where both the first dielectric layer and the second dielectric layer are between the fixed region and the spacer region, and a free region between the first dielectric layer and the second dielectric layer. The free region may be configured to have a first magnetic state and a second magnetic state. The free region may include an interface layer, a multilayer structure, an insertion layer (e.g., a metallized insertion layer), one or more ferromagnetic layers (e.g., metallized ferromagnetic layers), and/or a transition layer (e.g., a metallized transition layer).

Magnetoresistive devices and methods therefor

A method of fabricating a magnetoresistive device may comprise forming an electrically conductive region and forming a first seed region on one side of the electrically conductive region. A surface of the first seed region may be treated by exposing the surface to a gas. A second seed region may be formed on the treated surface of the first seed region. The method may also comprise forming a magnetically fixed region on one side of the second seed region.

Magnetoresistive stack device fabrication methods

Aspects of the present disclosure are directed to magnetoresistive stacks including regions having increased height-to-diameter ratios. Exemplary magnetoresistive stacks—for example, used in a magnetic tunnel junction (MTJ) magnetoresistive device—of the present disclosure include one or more multilayer synthetic antiferromagnetic structures—SAFs—or synthetic ferromagnetic structures—SyFs—(A) in order to promote stability of the SAF or SyF, e.g., for smaller-sized MTJs ().

A magnetoresistive stack includes a fixed magnetic region, one or more dielectric layers disposed on and in contact with the fixed magnetic region, and a free magnetic region disposed above the one or mom dielectric layers. The fixed magnetic region may include a first ferromagnetic region, a coupling layer, a second ferromagnetic region, a transition layer disposed, a reference layer, and at least one interfacial layer disposed above the second ferromagnetic region. Another interfacial layer may be disposed between the one or more dielectric layers and the free magnetic region.

A magnetically free region of magnetoresistive device includes at least a first ferromagnetic region and a second ferromagnetic region separated by a non-magnetic insertion region. At least one of the first ferromagnetic region and the second ferromagnetic region may include at least a boron-rich ferromagnetic layer positioned proximate a boron-free ferromagnetic layer.

Magnetoresistive stacks and methods therefor

A magnetoresistive stack/structure and method of manufacturing same comprising wherein the stack/structure includes a seed region, a fixed magnetic region disposed on and in contact with the seed region, a dielectric layer(s) disposed on the fixed magnetic region and a free magnetic region disposed on the dielectric layer(s). In one embodiment, the seed region comprises an alloy including nickel and chromium having (i) a thickness greater than or equal to 40 Angstroms (+/&#x2212;10%) and less than or equal to 60 Angstroms (+/&#x2212;10%), and (ii) a material composition or content of chromium within a range of 25-60 atomic percent (+/&#x2212;10%) or 30-50 atomic percent (+/&#x2212;10%).

In-plane spin orbit torque magnetoresistive stack/structure and methods therefor

Aspects of the present disclosure are directed to magnetic tunnel junction (MTJ) structures comprising multiple MTJ bits connected in series. For example, a magnetic tunnel junction (MTJ) stack according to the present disclosure may include at least a first MTJ bit and a second MTJ bit stacked above the first MTJ bit, and a resistance state of the MTJ stack may be read by passing a single read current through both the first MTJ bit and the second MTJ bit.

Stacked magnetoresistive structures and methods therefor

Spin-Hall (SH) material is provided near free regions of magnetoresistive devices that include magnetic tunnel junctions. Current flowing through such SH material injects spin current into the free regions such that spin torque is applied to the free regions. The spin torque generated from SH material can be used to switch the free region or to act as an assist to spin-transfer torque generated by current flowing vertically through the magnetic tunnel junction, in order to improve the reliability, endurance, or both of the magnetoresistive device. Further, one or more additional regions or manufacturing steps may improve the switching efficiency and the thermal stability of magnetoresistive devices.

Combined spin-orbit torque and spin-transfer torque switching for magnetoresistive devices and methods therefor

Spin-orbit-torque (SOT) lines are provided near free regions in magnetoresistive devices that include magnetic tunnel junctions. Current flowing through such SOT lines injects spin current into the free regions such that spin torque is applied to the free regions. The spin torque generated from a SOT switching line can be used to switching the free region or to act as an assist to spin-transfer torque generated by current flowing vertically through the magnetic tunnel junction, in order to improve the reliability, endurance, or both of the magnetoresistive device. Further, one or more additional layers or regions may improve the SOT switching efficiency and the thermal stability of magnetoresistive devices including SOT lines.

Spin orbit torque magnetoresistive devices and methods therefor

A magnetoresistive device may include a first ferromagnetic region, a second ferromagnetic region, and an intermediate region positioned between the first ferromagnetic region and the second ferromagnetic region. The intermediate region may be formed of a dielectric material and comprise at least two different metal oxides.

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Chandler, AZ, United States of America

Jijun Sun