Western Digital Technologies, Inc.

Goncalo Baiao De Albuquerque

Yukimasa Okada

Daniele Mauri

Xiaoyong Liu

Quang Le

Suping Song

Michael Kuok San Ho

Zhigang Bai

Ming Jiang

Kuok San Ho

Yuankai Zheng

Ming Mao

Feng Q Liu

Christian Kaiser

Alexander Michael Zeltser

Yaguang Wei

Yunfei Ding

Terence T Lam

Chih-Ching Hu

Yung-Hung Wang

Xinjiang Shen

Xiaohai Xiang

Songzi Wang

A dual free layer (DFL) read head or reader oftentimes has a sidebump in a signal amplitude vs. cross-track profile plot. The sidebump is a magnetic signal of the reader in response to the magnetic field of magnetic media with finite thickness. The sidebump magnitude is far below the main magnetic signal of the reader and is offset from the center of the track in the cross-track direction. When two sidebumps are present (one on each side of the center of the track), the sidebump should generally and ideally be symmetrically offset in the cross-track direction else there is a negative impact on reader performance. To obtain offset symmetry, a synthetic antiferromagnetic (SAF) shield may be used, magnetic moments of soft bias layers can be adjusted, and spacing between the free layers of the DFL read head and the layers of the soft bias can also be adjusted.

DFL reader signal sidebump imbalance reduction

A two-dimensional magnetic recording (TDMR) read head includes a lower reader and an upper reader. Each of the lower reader and the upper reader may have a dual free layer (DFL) magnetic tunnel junction structure having first and second free layers located between lower and upper shields. A synthetic antiferromagnetic (SAF) structure is located on a side of each magnetic tunnel junction. A sidewall insulating layer is located between the lower soft bias layer of the SAF structure and the first free layer. The sidewall insulating layer can have a reduced height such that an upper soft bias layer of the SAF structure is in direct contact with a sidewall of the second free layer, or the upper portion of the sidewall insulating layer located between the upper soft bias layer of the SAF structure and the sidewall of the second free layer has a reduced thickness.

Dual free layer read head having recessed sidewall insulator layer and method of making thereof

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.

Read head sensor with balanced shield design

Embodiments of the present disclosure generally relate to a large field range TMR sensor of magnetic tunnel junctions (MTJs) with a free layer having an intrinsic anisotropy. In one embodiment, a tunnel magnetoresistive (TMR) based magnetic sensor in a Wheatstone configuration includes at least one MTJ. The MTJ includes a free layer having an intrinsic anisotropy produced by deposition at a high oblique angle from normal. Magnetic domain formations within the free layer can be further controlled by a pinned layer canted at an angle to the intrinsic anisotropy of the free layer, by a hard bias element, by shape anisotropy, or combinations thereof.

TMR sensor with magnetic tunnel junctions with a free layer having an intrinsic anisotropy

The present disclosure generally relates to data storage devices, and more specifically, to a magnetic media drive employing a magnetic recording head. The head includes a trailing shield, a main pole, an STO disposed between the trailing shield and the main pole, and a non-magnetic conductive structure (or non-magnetic conductive layers) adjacent to the main pole and in contact with the STO. The non-magnetic conductive structure provides additional paths for electrical currents to flow to the STO. The non-magnetic conductive structure enables higher current density to the STO without creating hot spots at the MFS. Maximum current efficiency and uniformity can be achieved with the non-magnetic conductive structure.

Magnetic recording head with non-magnetic conductive structure surrounding a main pole and contacting a spin torque oscillator

Magnetic recording head with non-magnetic conductive structure

The present disclosure generally relates to a magnetic media drive employing a magnetic recording head. The head includes a main pole at a media facing surface (MFS), a trailing shield at the MFS, and a MAMR stack disposed between the main pole and the trailing shield at the MFS. The MAMR stack includes a seed layer and at least one magnetic layer. The seed layer is fabricated from a thermally conductive material having electrical resistivity lower than that of the main pole. The seed layer has a stripe height greater than a stripe height of the at least one magnetic layer. With the extended seed layer, the bias current from the trailing shield to the main pole spreads further away from the MFS along the extended seed layer before flowing into the main pole, reducing temperature rise at or near the MAMR stack, leading to improved write head reliability.

MAMR writer with low resistance MAMR stack

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San Jose, CA, United States of America

Goncalo Baiao De Albuquerque