公开(公告)号：US20210390978A1

公开(公告)日：2021-12-16

申请号：US16899366

申请日：2020-06-11

Applicant: Western Digital Technologies, Inc.

Inventor： Chih-Ching HU ,  Yung-Hung WANG ,  Ming MAO ,  Guanxiong LI ,  Daniele MAURI ,  Xiaoyong LIU ,  Yukimasa OKADA ,  Anup ROY ,  Chen-jung CHIEN ,  Hongxue LIU

IPC: G11B5/39

Abstract: The present disclosure generally related to a two dimensional magnetic recording (TDMR) read head having a magnetic tunnel junction (MTJ). Both the upper reader and the lower reader have a dual free layer (DFL) MTJ structure between two shields. A synthetic antiferromagnetic (SAF) soft bias structure bounds the MTJ, and a rear hard bias (RHB) structure is disposed behind the MTJ. The DFL MTJ decreases the distance between the upper and lower reader and hence, improves the area density capacity (ADC). Additionally, the SAF soft bias structures and the rear head bias structure cause the dual free layer MTJ to have a scissor state magnetic moment at the media facing surface (MFS).

公开(公告)号：US20240233762A1

公开(公告)日：2024-07-11

申请号：US18308576

申请日：2023-04-27

Applicant: Western Digital Technologies, Inc.

Inventor： Xiaoyong LIU ,  Songzi WANG ,  Ji LI ,  Yukimasa OKADA

IPC: G11B5/73 ,  G11B5/11

CPC classification number: G11B5/737 ,  G11B5/11

Abstract: Aspects of the present disclosure generally relate to magnetic recording heads of magnetic recording devices, such as magnetic read sensors of magnetic read heads of hard disk drives (HDD). In one implementation, a reader includes a magnetic seed layer and a shield layer. Two free layers are disposed between the magnetic seed layer and the shield layer. The magnetic seed layer and the shield layer are magnetized in opposite directions. In one or more embodiments, each of the magnetic seed layer and the shield layer is magnetized using a simple pinning arrangement having an antiferromagnetic (AFM) layer. In one or more embodiments, one of the magnetic seed layer or the shield layer is magnetized using a simple pinning arrangement having an AFM) layer, and the other of the magnetic seed layer or the shield layer is magnetized using a synthetic antiferromagnetic (SAF) pinning arrangement having an AFM layer.

公开(公告)号：US20250078864A1

公开(公告)日：2025-03-06

申请号：US18243053

申请日：2023-09-06

Applicant: Western Digital Technologies, Inc.

Inventor： Xiaoyong LIU ,  Zhanjie LI ,  Yaguang WEI ,  Yukimasa OKADA ,  Goncalo Marcos BAIÃO DE ALBUQUERQUE

IPC: G11B5/39

Abstract: The present disclosure generally relates to a dual free layer two dimensional magnetic recording read head. The read head comprises a lower shield, a first sensor disposed over the first lower shield, a first rear hard bias (RHB) structure recessed from a media facing surface (MFS), a first upper shield disposed over the first sensor, a middle shield disposed over the first sensor at the MFS, a second sensor disposed over the middle shield, a second RHB structure recessed from the MFS, and an upper shield disposed over the second sensor. The middle shield has a U-like shape and a ratio of a width to a throat height of 6:1, where the throat height is less than or equal to about 2 μm. The first and second RHB structures each individually has a stripe height about 3 times greater than a stripe height of the middle shield.

公开(公告)号：US20220028418A1

公开(公告)日：2022-01-27

申请号：US17448167

申请日：2021-09-20

Applicant: Western Digital Technologies, Inc.

Inventor： Xiaoyong LIU ,  Goncalo BAIAO DE ALBUQUERQUE ,  Daniele MAURI ,  Yukimasa OKADA

IPC: G11B5/39

Abstract: The present disclosure generally relates to a read head of a data storage device. The read head includes a read sensor sandwiched between two shields. The shields can have different materials as well as a different number of layers. Furthermore the shields can be fabricated by different processes and have different heights and thicknesses. The ratio of the thickness to the height for the shields are substantially identical to ensure that the saturation field are substantially identical and balanced.

公开(公告)号：US20220005501A1

公开(公告)日：2022-01-06

申请号：US17465455

申请日：2021-09-02

Applicant: Western Digital Technologies, Inc.

Inventor： Xiaoyong LIU ,  Ji LI ,  Changhe SHANG ,  Daniele MAURI ,  Yukimasa OKADA

IPC: G11B5/39

Abstract: Aspects of the present disclosure generally relate to magnetic recording heads of magnetic recording devices. A magnetic read head includes a first pinning layer magnetically oriented in a first direction, and a second pinning layer formed above the first pinning layer and magnetically oriented in a second direction that is opposite of the first direction. The magnetic read head includes a rear hard bias disposed outwardly of one or more of the first pinning layer relative or the second pinning layer. The rear hard bias is magnetically oriented to generate a magnetic field in a bias direction. The bias direction points in the same direction as the first direction or the second direction. The magnetic read head does not include an antiferromagnetic (AFM) layer between a lower shield and an upper shield.