Everspin Technologies, Inc.

Motorola Corporation

Freescale Semiconductor,inc.

International Business Machines Corporation

Jon Michael Slaughter

Nicholas David Rizzo

Renu Whig

Jijun Sun

Dimitri Houssameddine

Phillip G Mather

Srinivas V Pietambaram

Jason A Janesky

Sanjeev Aggarwal

Eugene Youjun Chen

Renu Whig Dave

Frederick B Mancoff

Han-Jong Chia

Saied N Tehrani

Kenneth H Smith

Bengt J Akerman

Thomas Andre

Mark A Durlam

Syed M Alam

Bradley Neal Engel

Kelly Wayne Kyler

Sumio Ikegawa

Gloria J Kerszykowski

Lianjun Liu

Sarin A Deshpande

Mark DeHerrera

Jing Shi

Philip Mather

Chih-Chao Yang

Michael Rizzolo

Ashim Dutta

Herbert Goronkin

Chitra K Subramanian

Theodore Zhu

Michael Tran

Anatoli A Korkin, Legal Representative

Michael Schneider

Theodorus E Standaert

John Christopher Arnold

Gregory W Grynkewich

Peter K Naji

Brian R Butcher

Eric John Salter

X Theodore Zhu

Mark F Deherrera

Steven M Smith

Gerald R Steiner

Hyunwoo Yang

Naganivetha Thiyagarajah

Ganesh Kolliyil Rajan

Charles W Snyder

John T Martin

Cong Hai

Johan Akerman

Shukai Ye

Phillip Lopresti

Jacob Wang Chenchen

Lanjun Liu

A magnetoresistive device includes a magnetically fixed region and a magnetically free region positioned on opposite sides of a tunnel barrier region. One or more transition regions, including at least a first transition region and second transition region, is positioned between the magnetically fixed region and the tunnel barrier region. The first transition region includes a non-ferromagnetic transition metal and the second transition region includes an alloy including iron and boron.

Magnetoresistive stack and methods therefor

An MRAM device is provided. The MRAM device includes a first dielectric cap layer formed on an underlying layer, a second dielectric cap layer formed on the first dielectric cap layer, the first dielectric cap layer including a lower-κ material than that of the second dielectric cap layer. The MRAM device also includes a bottom electrode contact (BEC) formed through the first dielectric cap layer and the second dielectric cap layer, an MRAM stack formed on the BEC, and wherein the second dielectric cap layer surrounds an upper portion of the BEC.

Layered bottom electrode dielectric for embedded MRAM

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

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 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 magnetic tunnel junction (MTJ) stack includes a free magnetic region, a fixed magnetic region, and a dielectric layer positioned between the free magnetic region and the fixed magnetic region. In one aspect, the fixed magnetic region consists essentially of an unpinned, fixed synthetic anti-ferromagnetic (SAF) structure which comprises (i) a first layer of one or more ferromagnetic materials, including cobalt, (ii) a multi-layer region including a plurality of layers of ferromagnetic materials, wherein the plurality of layers of ferromagnetic materials include a layer of one or more ferromagnetic materials including cobalt, and (iii) an anti-ferromagnetic coupling layer disposed between the first layer and the multi-layer region. The free magnetic region may include a circular shape, the one or more ferromagnetic materials of the first layer may include cobalt, iron and boron, and the dielectric layer may be disposed on the first layer.

Magnetoresistive stacks with an unpinned, fixed synthetic anti-ferromagnetic structure and methods of manufacturing thereof

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%).

A semiconductor process integrates three bridge circuits, each include magnetoresistive sensors coupled as a Wheatstone bridge on a single chip to sense a magnetic field in three orthogonal directions. The process includes various deposition and etch steps forming the magnetoresistive sensors and a plurality of flux guides on one of the three bridge circuits for transferring a 'Z' axis magnetic field onto sensors orientated in the XY plane.

Methods of manufacturing a magnetic field sensor

Three bridge circuits (), each include magnetoresistive sensors coupled as a Wheatstone bridge () to sense a magnetic field () in three orthogonal directions () that are set with a single pinning material deposition and bulk wafer setting procedure. One of the three bridge circuits () includes a first magnetoresistive sensor () comprising a first sensing element () disposed on a pinned layer (), the first sensing element () having first and second edges and first and second sides, and a first flux guide () disposed non-parallel to the first side of the substrate and having an end that is proximate to the first edge and on the first side of the first sensing element (). An optional second flux guide () may be disposed non-parallel to the first side of the substrate and having an end that is proximate to the second edge and the second side of the first sensing element ().

Three axis magnetic field sensor

A method of fabricating a magnetoresistive device includes etching a magnetoresistive stack using a first etching process to form one or more sidewalls, and etching the stack using a second etching process after forming the one or more sidewalls. Wherein, the second etching process may be relatively more isotropic than the first etching process.

Methods of manufacturing integrated circuits using isotropic and anisotropic etching processes

A magnetoresistive memory device that stores data in the synthetic antiferromagnet (SAF) included in each spin-torque memory cell provides for more robust data storage. In normal operation, the memory cells use the free portion of the memory cell for data storage. Techniques for storing data in the reference portions of memory cells are presented, where an unbalanced SAF that includes ferromagnetic layers having different magnetic moments is used to lower the switching barrier for the SAF and allow for writing data values to the SAF using lower currents and magnetic fields than would be required for a balanced SAF.

Data storage in synthetic antiferromagnets included in magnetic tunnel junctions

A magnetic field sensor that includes a differential bridge in which each path of the bridge includes a first type of magnetic field sensing device and a second type of magnetic field sensing device. The first and second types of magnetic field sensing devices differ in the magnetic moment imbalance present in the synthetic antiferromagnets (SAFs) included in their reference layers such that that different types of devices produce a different response to perpendicular magnetic fields, but the same response to in-plane magnetic fields. Such different magnetic moment imbalances in the SAFs of magnetic field sensing devices included in a bridge allow for accurate sensing of perpendicular magnetic fields in a differential manner that also cancels out interference from in-plane fields. Techniques for producing such magnetic field sensing devices on an integrated circuit are also presented. Moreover, the free layers within the magnetic field sensing devices can be adjusted in terms of their sensitivity range and level of sensitivity by manipulating the kink filed (Hk) for those free layers.

Magnetic field sensor and method of manufacture

Growing community of inventors

Tempe, AZ, United States of America

Jon Michael Slaughter