Hgst Netherlands, B.v.

Western Digital Technologies, Inc.

Hitachi Global Storage Technologies Netherlands B.v.

Norihiro Okawa

Takahiro Ibusuki

Koujiro Komagaki

Kouji Okazaki

Koji Sakamoto

Koji Okazaki

Kan Yasui

Katsuro Watanabe

Yoshibumi Matsuda

Nobuo Yoshida

Kouichi Nishioka

Yukimasa Okada

Kouji Kataoka

Takashi Wagatsuma

Masashi Hattori

Kojiro Komagaki

Hiroshi Akiyama

A magnetic read head is provided, comprising a bottom magnetic shield, a first free magnetic layer, a second free magnetic layer, and a top magnetic shield, arranged from bottom to top in this order in a stacking direction from a leading side to a trailing side of the read head. A non-soft bias layer is positioned below the top magnetic shield and on a back side of the first and the second free magnetic layers. The top magnetic shield has a unidirectional anisotropy, the magnetic moments of the top and the bottom magnetic shields are canted relative to a plane of the first and the second free magnetic layers, and the top and the bottom magnetic shields are decoupled from the non-soft bias layer and not magnetically coupled to a soft bias layer.

Coupled soft bias scissor type sensor

A magnetic read element having an additional magnetic layer, 'a floating magnetic shield', formed as a part of a capping structure of a magnetoresistive element. The capping structure is formed over the magnetic free layer and includes a magnetic layer that is located between first and second non-magnetic layers. The magnetic layer can advantageously be formed with a high magnetic permeability for increased signal amplitude and increased signal resolution. In addition, because the magnetic layer of the capping layer structure acts as a magnetic shield, it can reduce effective magnetic gap spacing for increased signal resolution.

Magnetic read head with floating trailing shield

A magnetic read head is provided, comprising a bottom magnetic shield, a first free magnetic layer, a second free magnetic layer, and a top magnetic shield, arranged from bottom to top in this order in a stacking direction from a leading side to a trailing side of the read head. A soft bias layer is positioned below the top magnetic shield and on a back side of the first free magnetic layer and second free magnetic layer. The soft bias layer is directly coupled to the top magnetic shield, and the top magnetic shield has a unidirectional anisotropy, thereby reducing the incidence of soft bias magnetization reversal and avoiding hysteresis in the transfer curve.

In one embodiment, a method for forming a magnetoresistive read head includes forming a fixed layer having a first ferromagnetic material that has a fixed direction of magnetization above a lower shield layer, forming a free layer having a second ferromagnetic material positioned above the fixed layer, the free layer having a non-fixed direction of magnetization, forming a first mask above the free layer, the first mask having a predetermined width based on a track width of a magnetic medium, etching the free layer down to the fixed layer using the first mask as a guide, wherein substantially none of the fixed layer is etched, and wherein the fixed layer extends beyond both sides of the free layer in a cross-track direction, and forming magnetic domain control films on both sides of the free layer in the cross-track direction, the magnetic domain control films including a soft magnetic material.

Higher stability read head utilizing a partial milling process

Embodiments disclosed herein generally relate to a TMR sensor for reading a recording from a magnetic recording medium using TMR, and in particular, to a magnetic capping structure of the TMR sensor. The sensor comprises a free layer and a magnetic capping structure. The magnetic capping structure comprises a ferromagnetic capping layer and an absorption layer formed on the ferromagnetic capping layer. The absorption layer is adapted to absorb molecules from the ferromagnetic capping layer and prevent the ferromagnetic capping layer from diffusing into the free layer.

Confinement magnetic cap

The present disclosure generally relates to a read head sensor in a magnetic recording head. The read head sensor comprises a dual capping layer in a sensor stack that may reduce magnetic coupling so as to enhance magnetic bias field, e.g., domain control, in the read head sensor. Furthermore, an upper shield with multiple film stack having different film properties may also be utilized to enhance bias field generated to the read head sensor. Additionally, a coil structure may be positioned adjacent to a side shield to enhance bias field generation in the read head sensor.

Dual capping layer utilized in a magnetoresistive effect sensor

In one embodiment, a magnetic head includes a magnetoresistive sensor having a free layer and a soft magnetic layer adapted to control a magnetization direction of the free layer and a magnetic domain of the free layer, wherein a close-packed plane of the soft magnetic layer is positioned parallel to an air bearing surface (ABS) of the magnetic head. In another embodiment, a method for forming a magnetic head includes forming a magnetoresistive sensor having a free layer above a substrate and forming a soft magnetic layer adapted to control a magnetization direction of the free layer and a magnetic domain of the free layer, wherein a close-packed plane of the soft magnetic layer is positioned parallel or oblique to an ABS of the magnetic head.

Magnetic head having a soft magnetic layer with a close-packed plane thereof being parallel or oblique to an air bearing surface

In one embodiment, a magnetic head includes a sensor stack of thin films including a free layer; a hard bias structure comprising a first foundation layer, a second foundation layer formed on the first foundation layer and a hard bias layer formed above the second foundation layer, wherein portions of the first and second foundation layers positioned along a side wall of the sensor stack have a discrete island structure. Additional embodiments are also disclosed.

Easy axis hard bias structure

In one embodiment, a magnetic head includes a magnetoresistance effect sensor including a free layer, a hard bias magnetic film adapted for performing magnetic domain control of the free layer by biasing a magnetization direction of the free layer towards a predefined direction that is positioned on both sides of the free layer in a track-width direction, an upper shield positioned above the hard bias magnetic film and the magnetoresistance effect sensor; and an antiferromagnetic (AFM) layer positioned above the upper shield. The upper shield includes first and second upper shield layers, and an AFM coupling layer positioned between the first upper shield layer and the second upper shield layer that is adapted for antiferromagnetically coupling the first upper shield layer and the second upper shield layer, wherein a magnetization of the first upper shield layer is antiparallel with a magnetization of the hard magnetic bias layer.

Magnetic shield having improved resistance to the hard bias magnetic field

According to one embodiment, a method for producing a magnetic head includes depositing a first film above a substrate, etching a pattern into the first film, depositing a second film on the etched portion of the first film, and depositing a third film above the first and second film to form a multilayer magnetic film, wherein the second film is embedded between the first and third film in a portion of the first film that is removed. In another embodiment, a differential magnetic read head includes a magnetic multilayer film comprising a stack of a first magnetic sensor film and a second magnetic sensor film which are not magnetically connected and a hard magnetic film provided on both sides in a track width direction of the magnetic multilayer film for controlling a magnetic domain of the magnetic multilayer film. The hard magnetic film is a laminated structure as described above.

Magnetic head having a multilayer magnetic film and method for producing the same

A magnetic read head having a novel magnetic bias structure that provides improved magnetic biasing for improved free layer robustness and reduced Barkhausen noise. The bias structure includes hard magnetic layer formed over first and second under-layers. At least a portion of the first under-layer is formed as discrete islands of material, and the second under-layer is formed over the first under-layer. The first under-layer has a thickness of 0.25 to 0.75 nm. The novel seed layer structure causes hard magnetic layer to have a magnetic anisotropy that is substantially parallel with the free layer of the sensor stack even in regions adjacent to the sensor stack.

Growing community of inventors

Odawara, Japan

Norihiro Okawa