Magnetic sensor array with dual TMR film

Patent metadata

Field	Value
Publication number	US-11385305-B2
Application number	US-201916718667-A
Country	US
Kind code	B2
Filing date	Dec 18, 2019
Priority date	Aug 27, 2019
Publication date	Jul 12, 2022
Grant date	Jul 12, 2022

Abstract

A tunneling magnetoresistance (TMR) sensor device is disclosed that includes one or more TMR sensors. The TMR sensor device comprises a first resistor comprising a first TMR film, a second resistor comprising a second TMR film different than the first TMR film, a third resistor comprising the second TMR film, and a fourth resistor comprising the first TMR film. The first TMR film comprises a reference layer having a first magnetization direction anti-parallel to a second magnetization direction of a pinned layer. The second TMR film comprises a reference layer having a first magnetization direction parallel to a second magnetization direction of a first pinned layer, and a second pinned layer having a third magnetization direction anti-parallel to the first magnetization direction of the reference layer and the second magnetization direction of the first pinned layer.

First claim

What is claimed is:

1. A tunneling magnetoresistance (TMR) sensor device, comprising:
at least one TMR sensor comprising a first TMR film, the first TMR film comprising a first reference layer having a first magnetization direction, a first pinned layer having a second magnetization direction, a first free layer, a first barrier layer, a first spacer layer, a first antiferromagnetic layer, and a first seed layer, the first magnetization direction of the first reference layer being anti-parallel to the second magnetization direction of the first pinned layer,
wherein the first pinned layer comprises a multi-layer stack comprising Cobalt (Co), Cobalt-iron (CoFe), and Co having a thickness between 20 Angstroms and 30 Angstroms, and
wherein the first reference layer comprises a multilayer stack comprising CoFe, Tantalum (Ta), Cobalt-iron-boron (CoFeB), and CoFe having a thickness between 21 Angstroms and 37 Angstroms; and

at least one TMR sensor comprising a second TMR film, the second TMR film comprising a second reference layer having a third magnetization direction, a second pinned layer having the third magnetization direction, a third pinned layer having a fourth magnetization direction, a second free layer, a second barrier layer, a second spacer layer, a third spacer layer, a second antiferromagnetic layer, and a second seed layer, the third magnetization direction of the second reference layer and the second pinned layer being anti-parallel to the fourth magnetization direction of the third pinned layer,
wherein the second pinned layer comprises a multi-layer stack comprising Co, CoFe, and Co having a thickness between 20 Angstroms and 30 Angstroms,
wherein the third pinned layer comprises a multi-layer stack comprising Co, CoFe, and Co having a thickness between 35 Angstroms and 55 Angstroms,
wherein the second reference layer comprises a multilayer stack comprising CoFe, Ta, CoFeB, and CoFe having a thickness between 21 Angstroms and 37 Angstroms.

2. The TMR sensor device of claim 1 , wherein the at least one TMR sensor comprised of the first TMR film comprises a first TMR sensor and a fourth TMR sensor, and wherein the at least one TMR sensor comprised of the second TMR film comprises a second TMR sensor and a third TMR sensor.

3. The TMR sensor device of claim 2 , wherein the first TMR sensor is adjacent to the second TMR sensor and the third TMR sensor, the second TMR sensor is adjacent to the first TMR sensor and the fourth TMR sensor, the third TMR sensor is adjacent to the first TMR sensor and the fourth TMR sensor, and the fourth TMR sensor is adjacent to the second TMR sensor and the third TMR sensor.

4. The TMR sensor device of claim 1 , wherein the first barrier layer is disposed between the first reference layer and the first free layer, the first spacer layer is disposed between the first reference layer and the first pinned layer, and the first antiferromagnetic layer is disposed between the first pinned layer and the first seed layer.

5. The TMR sensor device of claim 1 , wherein the second barrier layer is disposed between the second reference layer and the second free layer, the second spacer layer is disposed between the second reference layer and the third pinned layer, the third spacer layer is disposed between the third pinned layer and the second pinned layer, and the second antiferromagnetic layer is disposed between the second pinned layer and the second seed layer.

6. The TMR sensor device of claim 5 , wherein the first TMR film has a total thickness of about 120 Angstroms to about 630 Angstroms, and wherein the second TMR film has a total thickness of about 155 Angstroms to about 1,675 Angstroms.

7. The TMR sensor device of claim 1 , wherein a Co composition in CoFe of the multilayer stack comprising Co, CoFe, and Co of the first pinned layer is between about 25% and 70%, wherein a B composition in CoFeB of the multilayer stack comprising CoFe, Ta, CoFeB, and CoFe of the first reference layer is between about 15% and 25%, wherein a Co composition in CoFe of the comprising Co, CoFe, and Co multilayer stack of the second pinned layer is between about 25% and 70%, and wherein a Co composition in CoFe of the multilayer stack comprising Co, CoFe, and Co of the third pinned layer is between about 25% and 70%.

8. A TMR sensor device, comprising:
a first resistor comprising a first TMR film, the first TMR film comprising a first reference layer having a first magnetization direction, a first free layer, a first barrier layer, a first spacer layer, a first pinned layer, a first antiferromagnetic layer, and a first seed layer, wherein the first reference layer comprises a multilayer stack comprising Cobalt-iron (CoFe), Tantalum (Ta), Cobalt-iron-boron (CoFeB), and CoFe having a thickness between 21 Angstroms and 37 Angstroms;
a second resistor comprising a second TMR film, the second TMR film comprising a second reference layer having a second magnetization direction, a second free layer, a second barrier layer, a second spacer layer, a second pinned layer, a third spacer layer, a third pinned layer, a second antiferromagnetic layer, and a second seed layer, wherein the second reference layer comprises a multilayer stack comprising CoFe, Ta, CoFeB, and CoFe having a thickness between 21 Angstroms and 37 Angstroms, and wherein the first magnetization direction of the first reference layer of the first TMR film is anti-parallel to the second magnetization of the second reference layer of the second TMR film;
a third resistor comprising the second TMR film; and
a fourth resistor comprising the first TMR film.

9. The TMR sensor device of claim 8 , wherein the first barrier layer is disposed between the first reference layer and the first free layer, the first spacer layer is disposed between the first reference layer and the first pinned layer, and the first antiferromagnetic layer is disposed between the first pinned layer and the first seed layer, and
wherein the second barrier layer is disposed between the second reference layer and the second free layer, the second spacer layer is disposed between the second reference layer and the third pinned layer, the third spacer layer is disposed between the third pinned layer and the second pinned layer, and the second antiferromagnetic layer is disposed between the second pinned layer and the second seed layer.

10. The TMR sensor device of claim 9 , wherein the third pinned layer of the second TMR film has a third magnetization direction parallel to the first magnetization direction of the first reference layer of the first TMR film.

11. The TMR sensor device of claim 9 , wherein the first free layer of the first TMR film has a fourth magnetization direction parallel to a fifth magnetization direction of the second free layer of the second TMR film.

12. The TMR sensor device of claim 11 , wherein the fourth magnetization of the first free layer of the first TMR film is parallel to a sixth magnetization direction of the first pinned layer of the first TMR film.

13. The TMR sensor device of claim 9 , wherein the first pinned layer of the first TMR film comprises a multi-layer stack comprising Co, CoFe, and Co having a thickness between 20 Angstroms and 30 Angstroms, wherein the second pinned layer of the second TMR film comprises a multi-layer stack comprising Co, CoFe, and Co having a thickness between 20 Angstroms and 30 Angstroms, and wherein the third pinned layer of the second TMR film comprises a multi-layer stack comprising Co, CoFe, and Co having a thickness between 35 Angstroms and 55 Angstroms.

14. The TMR sensor device of claim 13 , wherein the first TMR film has a tot

Assignees

• Western Digital Tech Inc

Inventors

• Zheng Yuankai
• Kaiser Christian
• Diao Zhitao
• Hu Chih-Ching
• Chien Chen-Jung
• Wang Yung-Hung
• Wan Dujiang
• Zhou Ronghui
• Mao Ming
• Jiang Ming
• Mauri Daniele

Classifications

• G01R33/0052

  Manufacturing aspects; Manufacturing of single devices, i.e. of semiconductor magnetic sensor chips (devices based on galvano-magnetic effect or the like H10N50/85) · CPC title

• H10N59/00

  Integrated devices, or assemblies of multiple devices, comprising at least one galvanomagnetic or Hall-effect element covered by groups H10N50/00 - H10N52/00 (MRAM devices H10B61/00) · CPC title

• H10N50/85

  Materials of the active region · CPC title

• H01F10/3272

  by use of anti-parallel coupled [APC] ferromagnetic layers, e.g. artificial ferrimagnets [AFI], artificial [AAF] or synthetic [SAF] anti-ferromagnets · CPC title

• H01F41/302

  for applying spin-exchange-coupled multilayers, e.g. nanostructured superlattices (spin-exchange-coupled multilayers H01F10/32) · CPC title