公开(公告)号：US10461243B2

公开(公告)日：2019-10-29

申请号：US15888136

申请日：2018-02-05

Applicant: EVERSPIN TECHNOLOGIES, INC.

Inventor： Han-Jong Chia ,  Jon Slaughter

IPC: H01L21/68 ,  H01L43/08 ,  G11C11/16 ,  H01F10/32 ,  H01L43/10 ,  H01L27/22

Abstract: Techniques for configuring the layers included in the free portion of a spin-torque magnetoresistive device are presented that allow for characteristics of the free portion to be tuned to meet the needs of various applications. In one embodiment, high data retention is achieved by balancing the perpendicular magnetic anisotropy of the ferromagnetic layers in the free portion. In other embodiments, imbalanced ferromagnetic layers provide for lower switching current for the magnetoresistive device. In various embodiments, different coupling layers can be used to provide exchange coupling between the ferromagnetic layers in the free portion, including oscillatory coupling layers, ferromagnetic coupling layers using materials that can alloy with the neighboring ferromagnetic layers, and discontinuous layers of dielectric material such as MgO that result in limited coupling between the ferromagnetic layers and increases perpendicular magnetic anisotropy (PMA) at the interface with those layers.

公开(公告)号：US10255961B2

公开(公告)日：2019-04-09

申请号：US15851816

申请日：2017-12-22

Applicant: Everspin Technologies, Inc.

Inventor： Han-Jong Chia ,  Sumio Ikegawa ,  Michael Tran ,  Jon Slaughter

IPC: G11C11/16 ,  H01L43/08 ,  H01L43/02 ,  H01L43/12 ,  H01F10/32 ,  H01L43/10 ,  G11C11/56

Abstract: 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.

公开(公告)号：US11114608B2

公开(公告)日：2021-09-07

申请号：US16519741

申请日：2019-07-23

Applicant: Everspin Technologies, Inc.

Inventor： Jijun Sun ,  Shimon ,  Han-Jong Chia

IPC: H01L43/04 ,  G11C11/16 ,  H01L27/22 ,  H01L43/06 ,  H01L43/14

Abstract: 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.

公开(公告)号：US10692926B2

公开(公告)日：2020-06-23

申请号：US16601848

申请日：2019-10-15

Applicant: Everspin Technologies, Inc.

Inventor： Jijun Sun ,  Sanjeev Aggarwal ,  Han-Jong Chia ,  Jon M. Slaughter ,  Renu Whig

IPC: H01L27/22 ,  H01L43/02 ,  H01L43/08 ,  G11C11/16 ,  H01L43/12 ,  G11B5/39 ,  H01L43/10

Abstract: 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%).

公开(公告)号：US20190123098A1

公开(公告)日：2019-04-25

申请号：US16195178

申请日：2018-11-19

Applicant: Everspin Technologies, Inc.

Inventor： Jijun SUN ,  Sanjeev Aggarwal ,  Han-Jong Chia ,  Jon M. Slaughter ,  Renu Whig

IPC: H01L27/22 ,  H01L43/02 ,  H01L43/08 ,  H01L43/10 ,  H01L43/12 ,  G11B5/39 ,  G11C11/16

Abstract: 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%).

公开(公告)号：US10141498B2

公开(公告)日：2018-11-27

申请号：US15373880

申请日：2016-12-09

Applicant: Everspin Technologies, Inc.

Inventor： Renu Whig ,  Jon M. Slaughter ,  Han-Jong Chia

IPC: H01L29/82 ,  H01L43/02 ,  H01L43/08 ,  H01L43/10 ,  H01L43/12

Abstract: 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%).