Hitachi Global Storage Technologies Netherlands B.v.

Hitachi Global Storage Technologies Japan, Ltd.

Hitachi, Ltd.

Hgst Netherlands, B.v.

Taku Shintani

Katsuro Watanabe

Nobuo Yoshida

Kikuo Kusukawa

Hisako Takei

Kenichi Meguro

Masahiro Osugi

Masafumi Mochizuki

Hiroyuki Hoshiya

Yohji Maruyama

Hisashi Kimura

Tomohiro Okada

Kouichi Nishioka

Kazuhiro Ueda

Masahiko Hatatani

Tadashi Umezawa

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

Embodiments of the present invention help to provide a method for manufacturing a perpendicular magnetic recording head including a main magnetic pole having a width that does not generally vary. According to one embodiment, a magnetic film, a first inorganic mask film, an organic film, a second inorganic mask film, and a resist pattern are formed in this order. Reactive ion etching (RIE) is performed using the resist pattern as a mask to etch the second inorganic mask film and the organic film and form a mask for the subsequent step. A flow rate of an Ar gas is then controlled, and ion milling is performed, to correct a difference between the width of the mask located at the central portion of the wafer and the width of the mask located at the outer peripheral portion of the wafer. The magnetic film is processed to have a uniform track width. Ion milling is then performed to form the main magnetic pole having an inverted trapezoidal shape.

Method for manufacturing perpendicular magnetic recording head

Embodiments in accordance with the present invention provide a sensor to produce high output with a small track width. Particular embodiments include forming a magnetoresistive sensor of a read head to be substantially vertical in its upper portion and gently upwardly convexly curved in its lower portion.

Magnetic head and method for fabricating the same

Embodiments in accordance with the present invention reduce the influence of etching damage at junction edge of a magnetoresistive film in the sensor height direction, lower the deterioration of dielectric breakdown voltage between an upper magnetic shield layer and a lower magnetic shield layer and instability of reproducing property resulting from shield process, and maintain electrostatic capacity to a small value in a CPP magnetoresistive head. In an embodiment of a magnetoresistive head of the present invention, length in the sensor height direction of bottom surface of a pinning layer is longer than the length in the sensor height direction of bottom surface of a first ferromagnetic layer. The angle formed by an edge in the sensor height direction of the pinning layer to the surface extended from a bottom surface of a magnetoresistive film is smaller than the angle formed by an edge in the sensor height direction of a second ferromagnetic layer to the surface extended from a bottom surface of the magnetoresistive film. Height of top surface of a sensor height direction refill film is equal to or higher than the top surface of the magnetoresistive film.

Magnetoresistive head and a manufacturing method thereof

A high output magneto-resistive sensor is provided by suppressing leftover resist mask after lift-off and generation of a fence, and by making it easy to remove the redepositions deposited on the side wall in the track width direction or on the side wall in the sensor height direction of the magnetoresistive film. As a means to solve a fence and lift-off leftover of a resist in a process for forming a track and a process for forming a sensor height, a stopper layer is provided on the magnetoresistive film and the stopper layer on the refill film, and performing lift-off by CMP. By using a metallic material which has a small CMP polishing rate for at least the first stopper layer, the magnetoresistive film and the first stopper layer can be etched simultaneously and a pattern formed. As a result, decrease of the height of the resist mask by RIE can be suppressed and lift-off leftover can be prevented.

Magneto-resistive sensor having small track width and sensor height using stopper layer

A fabrication method for thin film magnetic heads, comprises, forming a Current Perpendicular to a Plane (CPP) sensor film over a lower shield and a first chemical mechanical polishing (CMP) stop film over the CPP sensor film, etching the CPP sensor film and forming a track width on the CPP sensor film, and covering at least the etching section of the CPP sensor film with an insulating film. The method further comprises forming a CMP dummy film over the insulating film and a second CMP stop film over the CMP dummy film, exposing the first CMP stop film, and removing the first CMP stop film and the second CMP stop film by oxygen reactive ion etching (RIE) and the CMP dummy film by fluorine RIE, and forming an upper shield film over the insulating film and over the CPP sensor film.

Fabrication method for thin film magnetic heads

This invention provides a high-output magnetic head with a high yield, which is capable of minimizing sense current leak or noise caused by a shift of the magnetic wall of an upper shield layer. In one embodiment, the magnetic head is fabricated so that the height of the upper surface of the refill film along the sensor height direction is the same as that of the magnetoresistance layer in a portion where the refill film along the sensor height direction comes in contact with the magnetoresistance layer and the distance from the upper surface of the refill film along the sensor height direction to the upper surface of the lower shield layer gradually increases in a region from the portion where the refill film along the sensor height direction comes in contact with the magnetoresistance layer to a point at a certain distance away from the portion.

Magnetic head, fabrication process of magnetic head, and magnetic disk storage apparatus mounting magnetic head

A magnetic sensor includes a spacer having at least a nonmagnetic metal layer inserted between the upper shield layer and the longitudinal bias layers or between the upper shield layer and the longitudinal bias layers plus the magnetoresistive film, the shortest distance between the longitudinal bias layers and the free layer of the magnetoresistive film is set smaller than the shortest distance between the longitudinal bias layers and the upper shield layer, and this arrangement ensures that the amount of magnetic flux entering the magnetoresistive film from the longitudinal bias layers is larger than that absorbed by the upper shield layer, thus realizing a magnetic sensor whose Barkhausen noise is suppressed.

Magnetic sensor having a free layer containing a single magnetic domain

A high output, magnetoresistive head with a CPP structure is disclosed which reduces or prevents deformation near the air bearing surface of the read element portion layer at the time of air bearing surface processing. In the CPP structure magnetoresistive head, the deformation near the air bearing surface as a result of mechanical polishing during the air bearing surface processing can be reduced by forming deformation prevention layers having a higher shear modulus than the first ferromagnetic layer, and a second ferromagnetic layer between a magnetoresistive film and at least one of a lower shield layer and an upper shield layer.

CPP-type magnetic head with less deformation and a magnetic recording/reproducing system using the same

A high output, magnetoresistive head with a CPP structure is disclosed which reduces or prevents deformation near the air bearing surface of the read element portion layer at the time of air bearing surface processing. In the CPP structure magnetoresistive head, the deformation near the air bearing surface as a result of mechanical polishing during the air bearing surface processing can be reduced by forming deformation prevention layers having a higher shear modulus than a first ferromagnetic layer, and a second ferromagnetic layer between a magnetoresistive film and at least one of a lower shield layer and an upper shield layer.

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Kanagawa, Japan

Taku Shintani