公开(公告)号：US20200251525A1

公开(公告)日：2020-08-06

申请号：US16266232

申请日：2019-02-04

Applicant: International Business Machines Corporation

Inventor： Daniel Worledge ,  Guohan Hu

IPC: H01L27/22 ,  H01L43/12 ,  H01L43/10 ,  H01L43/08

Abstract: A multilayered magnetic free layer structure is provided that includes a first magnetic free layer and a second magnetic free layer separated by a non-magnetic layer in which the first magnetic free layer is composed of an ordered magnetic alloy. The ordered magnetic alloy provides a first magnetic free layer that has low moment, but is strongly magnetic. The use of such an ordered magnetic alloy first magnetic free layer in a multilayered magnetic free layer structure substantially reduces the switching current needed to reorient the magnetization of the two magnetic free layers.

公开(公告)号：US20200243749A1

公开(公告)日：2020-07-30

申请号：US16262396

申请日：2019-01-30

Applicant: International Business Machines Corporation

Inventor： Daniel Worledge ,  Guohan Hu

IPC: H01L43/02 ,  H01L43/10 ,  H01L43/12 ,  H01L27/22

Abstract: A multilayered magnetic free layer structure is provided that includes a first magnetic free layer and a second magnetic free layer separated by a non-magnetic layer in which the second magnetic free layer is composed of a M1/M2 superlattice structure or a M1/M2 multilayer structure, wherein M1 is a first magnetic metal selected from the group consisting of cobalt (Co), iron (Fe) and alloys thereof, and M2 is a second magnetic metal selected from the group consisting of platinum (Pt), palladium (Pd), nickel (Ni), rhodium (Rh), iridium (Jr), rhenium (Re) and alloys thereof.

公开(公告)号：US10600566B2

公开(公告)日：2020-03-24

申请号：US15292625

申请日：2016-10-13

Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION

Inventor： Guohan Hu ,  Naigang Wang

IPC: H01F7/06 ,  H01F41/04 ,  H01F27/28 ,  H01F17/00 ,  H01F3/10

Abstract: A planar magnetic structure includes a closed loop structure having a plurality of core segments divided into at least two sets. A coil is formed about one or more core segments. A first antiferromagnetic layer is formed on a first set of core segments, and a second antiferromagnetic layer is formed on a second set of core segments. The first and second antiferromagnetic layers include different blocking temperatures and have an easy axis pinning a magnetic moment in two different directions, wherein when current flows through the coil, the magnetic moments rotate to form a closed magnetic loop in the closed loop structure.

公开(公告)号：US10510391B2

公开(公告)日：2019-12-17

申请号：US15802838

申请日：2017-11-03

Applicant: International Business Machines Corporation ,  Samsung Electronics Co., Ltd.

Inventor： Guohan Hu ,  Jeong-Heon Park ,  Daniel C. Worledge

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

Abstract: Embodiments of the invention are directed to a magnetic tunnel junction (MTJ) storage element that includes a reference layer, a tunnel barrier and a free layer on an opposite side of the tunnel barrier layer from the reference layer. The reference layer has a fixed magnetization direction. The free layer includes a first region, a second region and a third region. The third region is formed from a third material that is configured to magnetically couple the first region and the second region. The first region is formed from a first material having a first predetermined magnetic moment, and the second region is formed from a second material having a second predetermined magnetic moment. The first predetermined magnetic moment is lower that the second predetermined magnetic moment.

公开(公告)号：US10453509B2

公开(公告)日：2019-10-22

申请号：US15802827

申请日：2017-11-03

Applicant: International Business Machines Corporation

Inventor： Guohan Hu ,  Daniel C. Worledge

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

Abstract: Embodiments of the invention are directed to a magnetic tunnel junction (MTJ) storage element that includes a reference layer, a tunnel barrier and a free layer on an opposite side of the tunnel barrier layer from the reference layer. The reference layer has a fixed magnetization direction. The free layer includes a first region, a second region and a third region. The third region is formed from a third material that is configured to magnetically couple the first region and the second region. The first region is formed from a first material having a first predetermined magnetic moment, and the second region is formed from a second material having a second predetermined magnetic moment. The first predetermined magnetic moment is lower that the second predetermined magnetic moment.

公开(公告)号：US10374145B2

公开(公告)日：2019-08-06

申请号：US14883283

申请日：2015-10-14

Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION

Inventor： Stephen L. Brown ,  Guohan Hu ,  Jonathan Z. Sun ,  Daniel C. Worledge

IPC: H01L43/12 ,  H01L43/02 ,  H01L27/22 ,  H01L43/10 ,  H01L43/08

Abstract: A method for forming a memory device that includes providing a free layer of an alloy of cobalt (Co), iron (Fe) and boron (B) overlying a reference layer; and forming metal layer comprising a boron (B) sink composition atop the free layer. Boron (B) may be diffused from the free layer to the metal layer comprising the boron sink composition. At least a portion of the metal layer including the boron (B) sink composition is removed. A metal oxide is formed atop the free layer. The free layer may be a crystalline cobalt and iron alloy. An interface between the metal oxide and free layer can provide perpendicular magnetic anisotropy character.

公开(公告)号：US10347827B2

公开(公告)日：2019-07-09

申请号：US15945220

申请日：2018-04-04

Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION

Inventor： Guohan Hu

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

Abstract: A method of making a spin-torque transfer magnetic random access memory device (STT MRAM) device includes forming a tunnel barrier layer on a reference layer; forming a free layer on the tunnel barrier layer, the free layer comprising a cobalt iron boron (CoFeB) alloy layer and an iron (Fe) layer; and performing a sputtering process to form a metal oxide layer on the Fe layer.

公开(公告)号：US20190140165A1

公开(公告)日：2019-05-09

申请号：US16242555

申请日：2019-01-08

Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION ,  SAMSUNG ELECTRONICS, CO., LTD.

Inventor： Guohan Hu ,  Younghyun Kim ,  Chandrasekara Kothandaraman ,  Jeong-Heon Park

IPC: H01L43/08 ,  H01L27/22

CPC classification number: H01L43/08 ,  H01L27/226 ,  H01L43/02 ,  H01L43/10 ,  H01L43/12

Abstract: Memory devices and methods of forming the same include forming a memory stack over a bottom electrode. The memory stack has a free magnetic layer formed on the tunnel barrier layer. A first boron-segregating layer is formed directly on the free magnetic layer. An anneal is performed to cause boron to leave the free magnetic layer at an interface with the first boron-segregating layer. A top electrode is formed over the memory stack.

公开(公告)号：US20180277748A1

公开(公告)日：2018-09-27

申请号：US15465050

申请日：2017-03-21

Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION ,  SAMSUNG ELECTRONICS, CO., LTD.

Inventor： Guohan Hu ,  Younghyun Kim ,  Chandrasekara Kothandaraman ,  Jeong-Heon Park

IPC: H01L43/08 ,  H01L27/22

CPC classification number: H01L43/08 ,  H01L27/226 ,  H01L43/02 ,  H01L43/10 ,  H01L43/12

Abstract: Memory devices and methods of forming the same include forming a memory stack over a bottom electrode. The memory stack has a fixed magnetic layer, a tunnel barrier layer on the fixed magnetic layer, and a free magnetic layer formed on the tunnel barrier layer. A boron-segregating layer is formed directly on the free magnetic layer. The memory stack is etched into a pillar. A top electrode is formed over the pillar.

公开(公告)号：US09978935B2

公开(公告)日：2018-05-22

申请号：US15364409

申请日：2016-11-30

Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION

Inventor： Guohan Hu

IPC: H01L21/00 ,  H01L43/12 ,  H01L43/08 ,  H01L43/10 ,  H01L43/02

CPC classification number: H01L43/12 ,  H01L43/02 ,  H01L43/08 ,  H01L43/10

Abstract: A method of making a spin-torque transfer magnetic random access memory device (STT MRAM) device includes forming a tunnel barrier layer on a reference layer; forming a free layer on the tunnel barrier layer, the free layer comprising a cobalt iron boron (CoFeB) alloy layer and an iron (Fe) layer; and performing a sputtering process to form a metal oxide layer on the Fe layer.