Hgst Netherlands, B.v.

Hitachi, Ltd.

Hitachi Global Storage Technologies Netherlands B.v.

Western Digital Technologies, Inc.

Kouichi Nishioka

Shinji Narishige

Takao Imagawa

Masaaki Sano

Masashi Hattori

Kenichi Meguro

Tetsuo Kobayashi

Toshihiro Yoshida

Koujiro Komagaki

Satoshi Shigematsu

Nobuo Yoshida

Jinshan Li

Masanobu Hanazono

Shigeru Tadokoro

Katsuya Mitsuoka

Takashi Wagatsuma

Kouji Okazaki

Hardayal Singh Gill

Zheng Gao

Quang Le

Ching Hwa Tsang

Masafumi Mochizuki

Yutaka Sugita

Moriaki Fuyama

Yohji Maruyama

Masaaki Hayashi

Alexander Michael Zeltser

Katsumi Hoshino

Takashi Onishi

Reiko Arai

Susumu Soeya

Koji Sakamoto

Yokuo Saitoh

Sangmun Oh

Eiji Ashida

Norihiro Okawa

Hideki Mashima

Chiseki Haginoya

Taku Shintani

Norihiro Ookawa

Yasunari Tajima

Masahiko Hatatani

Akira Kumagai

Takao Yonekawa

Yoshikazu Tsuji

Kenneth Donald Mackay

Andy Cuong Tran

Atsushi Katou

A read head is provided with a scissors sensor. The read head may include a bottom magnetic shield, and a first non-magnetic seed layer, a magnetic seed layer, a second non-magnetic seed layer, an antiferromagnetic layer, a coupling layer, a first free magnetic layer, a spacer layer, and a second free magnetic layer positioned above the bottom magnetic shield, in this order. A pair of magnetic side shield layers may be positioned on respective sides of the second free magnetic layer.

Tunnel magnetoresistance magnetic sensor with scissor sensor and multi-seed layer configuration

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

In one embodiment, a magnetic read head includes an antiferromagnetic (AFM) layer including a MnIr alloy having an Lordered phase, a pinned layer positioned above the AFM layer, and a seed layer positioned directly below the AFM layer, wherein the seed layer includes a laminated structure with an upper layer including Ru being positioned above one or more additional layers. In another embodiment, a magnetic read head includes an AFM layer including a MnIr alloy having an Lordered phase, a pinned layer positioned above the AFM layer, and a seed layer positioned directly below the AFM layer, the seed layer including a laminated structure of Ta/Y/Ru, wherein Y is a layer having an element or an alloy. Other magnetic heads having a reduced amount of random telegraph noise (RTN) and methods of formation thereof are disclosed according to more embodiments.

Antiferromagnetic (AFM) grain growth controlled random telegraph noise (RTN) suppressed magnetic head

A magnetic sensor having an Ir seed layer for improved pinning robustness and improved sensor performance. The sensor includes an Ir seed layer formed directly beneath and in contact with a layer of antiferromagnetic material (AFM). The Ir seed layer improves the grain structure and smoothness of the above applied layers to significantly improve the performance and pinning robustness of the sensor. The use of the Ir seed layer reduces interlayer magnetic coupling of the layers, reduces surface roughness and increases the temperature at which the pinned layer looses it's pinning (i.e. raises the mean blocking temperature Tc of the pinned layer structure).

Magnetoresistive sensor having an Ir seed layer for improved pinned layer robustness

According to one embodiment, a magnetic head includes a lower magnetic shield positioned at a media facing surface of the head, a lower sensor positioned above the lower magnetic shield, the lower sensor including a lower free layer, a middle magnetic shield positioned above the lower sensor at the media facing surface of the head, and a back side antiferromagnetic (AFM) layer positioned behind the lower free layer in an element height direction, the back side AFM layer being configured to provide magnetic stabilization for the middle magnetic shield. In another embodiment, a method includes forming a lower sensor including a lower free layer, forming a back side AFM layer behind the lower free layer in an element height direction, and forming a middle magnetic shield above the lower sensor, wherein the back side AFM layer is configured to provide magnetic stabilization for the middle magnetic shield.

Multi-sensor (MIMO) head having a back side antiferromagnetic middle shield

In one embodiment, magnetic read head includes a seed layer including an amorphous alloy film and Ru film positioned thereon, and an antiferromagnetic (AFM) layer positioned above the seed layer, the AFM layer including an alloy of MnIr having an Lordered phase, the amorphous alloy including a Co&#x2014;X alloy having more Co than any other element, with X including at least one of: Zr, Nb, Ta, Hf, W, Si, and Al. In another embodiment, a method for forming a magnetic read head includes forming a seed layer above a substrate, heating at least the substrate to a first temperature in a range from about 150&#xb0; C. to about 300&#xb0; C., cooling at least the substrate to a second temperature of less than about 100&#xb0; C., and forming an AFM layer above the seed layer between the heating and the cooling, the AFM layer comprising a MnIr alloy.

Thermally stable low random telegraph noise sensor

A two-dimensional magnetic recording (TDMR) multi-sensor read head has three stacked sensors separated by magnetic shields. The lower sensor is the primary sensor that is always aligned with the target track. The middle sensor is spaced laterally from the lower sensor a distance substantially equal to the track pitch (TP). The upper sensor is aligned with the lower sensor. The spacing D between the lower and upper sensors is selected to be related to TP and a maximum skew angle, where the skew angle is the angle between a line orthogonal to the sensor and the data track that varies with radial position of the head. The read head is connected to circuitry that selects two of the three sensors to be the active sensors depending on the radial position of the head and thus the skew angle of the head.

Current-perpendicular-to-the-plane (CPP) magnetoresistive (MR) sensor structure with stacked sensors for minimization of the effect of head skew

A magnetic read head and associated circuitry for reducing side track noise and decreasing read width, thereby providing increased data density. The magnetic read head includes first and second sensor elements that are aligned with one another in a data track direction, with the first sensor element being wider than the second sensor element. Electrical circuitry is connected with the read head in such a manner as to read a first signal from the first sensor element and a second signal from a second sensor element. Because the second sensor element is wider than the first sensor element, it will read more side signal noise from adjacent data tracks than will the second sensor element. The circuitry connected with the first and second sensor element detects and distinguishes the side signal noise and separates it out from the data signal, based sensor width difference and location difference.

Dual magnetic sensor for multi-input magnetic recording

The embodiments of the present invention generally relate to a magnetic head having a silicon seed layer disposed between a lower shield and a metallic underlayer to enhance the unidirectional anisotropy in an antiferromagnetic layer disposed over the metallic underlayer.

Enhanced pinning property by inserted Si seed layer

According to one embodiment, a method for forming a magnetic head having a current perpendicular to plan (CPP) sensor, includes forming a magnetoresistance effect film, performing a subtractive process for defining a back edge and a height length of the magnetoresistance effect film, depositing an insulating film adjacent the back edge of the magnetoresistance effect film, and ion milling at least an upper surface of a first portion of the insulating film located closest to the magnetoresistance effect film, where the upper surface of the first portion of the insulating film lies substantially along a plane. After the ion milling, the insulating film has no overlap of the insulating film above and/or onto the magnetoresistance effect film and no bulging in a region immediately adjacent a boundary between the insulating film and the magnetoresistance effect film.

Higher stability read head using a read sensor with a flat back edge

A method for manufacturing a magnetic sensor that decreases area resistance and decreases MR ratio of the sensor by eliminating any oxide formation in the capping layer of the sensor. The method includes forming a sensor stack having a multi-layer capping structure formed there-over. The multi-layer capping structure can include first, second, third and fourth layers. The second layer is constructed of a material that is not easily oxidized and which is different from the first layer. The sensor can be formed using a mask that includes a carbon hard mask. After the sensor stack has been formed by ion milling, the hard mask can be removed by reactive ion etching. Then, a cleaning process is performed to remove the second, third and fourth layers of the capping layer structure using an end point detection method such as secondary ion mass spectrometry to detect the presence of the second layer.

Method of manufacturing a magnetic read sensor having a low resistance cap structure

A method for manufacturing a magnetic read sensor and a magnetic read sensor are provided. In one embodiment of the invention, the method includes providing a seed layer disposed over a substrate of the magnetic read sensor, providing a free layer disposed over a seed layer and providing a spacer layer disposed over the free layer. The method further includes providing a pinned layer disposed over the spacer layer. In one embodiment, the pinned layer includes cobalt and iron, wherein the concentration of iron in the pinned layer is between 33 and 37 atomic percent (at. %). The method further includes providing a pinning layer disposed over the pinned layer, wherein the pinning layer is in contact with the pinned layer.

Pinned layer in magnetoresistive sensor

A magnetoresistive head and a fabricating method thereof accomplishing high sensitivity and low noise are provided even if track width narrowing makes progress. In one embodiment, a pinned layer includes a laminate which includes at least two magnetic layers and where adjacent magnetic layers are coupled antiferromagnetically to each other, and a mechanism to apply a longitudinal biasing field to a free layer is made to function by laminating a nonmagnetic separate layer/longitudinal biasing layer/antiferromagnetic layer connecting the free layer and opposite a nonmagnetic conductive layer (or nonmagnetic tunneling barrier layer). Controlling a magnetization direction of the longitudinal biasing layer which bears application of a longitudinal biasing field to the pinned layer and free layer is achieved by annealing carried out while applying a magnetic field in a track width direction and applying a magnetic field at room temperature.

Magnetoresistive head with improved in-stack longitudinal biasing layers

Exchange coupling energy between an anti-ferromagnetic layer and a first ferromagnetic layer, and an anti-ferromagnetic coupling energy between the first ferromagnetic layer and a second ferromagnetic layer by way of an Ru anti-ferromagnetic coupling layer of a spin valve device are increased thereby increasing the magnetoresistance ratio and decreasing the coercivity of the free layer of the spin valve film. In an MnPt anti-ferromagnetic bottom type synthetic ferri-type spin valve film in which an underlayer, an anti-ferromagnetic layer comprising MnPt, a first ferromagnetic layer comprising CoFe, an anti-ferromagnetic coupling layer comprising Ru, a second ferromagnetic layer comprising CoFe, an intermediate non-magnetic layer comprising Cu, a free layer comprising synthetic films of CoFe and NiFe and a protective layer are stacked over a substrate, the Fe composition X in CoFeX of the first ferromagnetic layer is set as about: 20&#x3c;x&#x2266;50 at %.

Magnetoresistive head and manufacturing method thereof

A spin valve sensor in a read head has a spacer layer which is located between a self-pinned AP pinned layer structure and a free layer structure. The free layer structure is longitudinally stabilized by first and second hard bias layers which abut first and second side surfaces of the spin valve sensor. The AP pinned layer structure has an antiparallel coupling layer (APC) which is located between first and second AP pinned layers (AP) and (AP). The invention employs a resetting process for setting of the magnetic moments of the AP pinned layers by applying a field at an acute angle to the head surface in a plane parallel to the major planes of the layers of the sensor. The resetting process sets a proper polarity of each AP pinned layer, which polarity conforms to processing circuitry employed with the spin valve sensor.

Method for resetting pinned layer magnetization in a magnetoresistive sensor

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Hiratsuka, Japan

Kouichi Nishioka