Hitachi Global Storage Technologies Netherlands B.v.

Hgst Netherlands, B.v.

Hitachi Global Storage Technologies Japan, Ltd.

Norihiro Ookawa

Shuichi Kojima

Koji Okazaki

Hisashi Kimura

Atsushi Kato

Masatoshi Arasawa

Satoshi Shigematsu

Katsuro Watanabe

Naoki Koyama

Kenichi Meguro

Katsumi Hoshino

Koji Sakamoto

Kouichi Nishioka

Yukimasa Okada

Takahiro Ibusuki

Kouji Kataoka

Takashi Wagatsuma

Akira Morinaga

Yasunari Tajima

Wataru Kimura

Kikuo Kusukawa

Kouji Okazaki

Takao Yonekawa

Izuru Ishii

Shigeo Fujita

Atsushi Katou

Yasunobu Yanagisawa

In one embodiment, a magnetic head includes a lower shield, a read element positioned above the lower shield at a media-facing surface of the magnetic head, the read element having a free layer, an upper shield positioned above the read element, a first domain control layer having a direction of magnetization in a predetermined direction, the first domain control layer being configured to control a direction of magnetization of the free layer toward the predetermined direction, and a second domain control layer configured to have a magnetization in a same direction as the direction of magnetization of the first domain control layer, the second domain control layer being positioned above the first domain control layer, wherein the first domain control layer is a hard magnetic layer, and wherein the second domain control layer is a soft magnetic layer.

Magnetic head having two domain control layers for stabilizing magnetization of the hard bias layer

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

According to one embodiment, a magnetoresistive head has a magnetoresistive sensor film between a lower shield layer and an upper shield layer. The magnetoresistive sensor film is formed by stacking at least a pinning layer, a first ferromagnetic layer, an intermediate layer, and a second ferromagnetic layer, in which a sense current flows so as to pass through an interface between the intermediate layer and the second ferromagnetic layer, and a resistance change of the magnetoresistive sensor film in accordance with the change of an external magnetic field is detected. Also, a lateral side metal layer having an electric resistivity lower than the electric resistivity of the pinning layer is disposed at least on a side wall of the pinning layer among side walls of layers constituting the magnetoresistive sensor film, the lateral side metal layer being in contact with the lower shield layer. Other embodiments are described as well.

CPP structure magnetoresistive head

A main magnetic pole of a recording head is formed in an inverted trapezoidal shape by ion milling but, the long milling time poses a problem of variations in the inverted trapezoidal shape and the dimensional variations in track width. In one embodiment of the invention, a recording head is formed by first forming a lower magnetic pole, a gap layer, and conductor coils, forming an upper magnetic yoke over the gap layer at a position recessed from the air bearing surface, and forming an inorganic insulative layer in the recessed portion. A back magnetic pole connected with the upper magnetic yoke is formed on the back of the lower electrode. Successively, the upper surfaces of the inorganic insulative layer and the upper magnetic yoke are planarized, on which an underlayer film such as of Rh is formed. A magnetic layer is formed by stacking a plurality of thin magnetic films by sputtering over the underlayer film from the air bearing surface as far as the position overlapping the upper magnetic yoke. Successively, ion milling is applied to form a main magnetic pole of an inverted trapezoidal shape having a taper on the lateral surface as viewed from the air bearing surface.

Method of manufacturing a magnetic head

If the length of a track-defining section from an air bearing surface varies due to tolerance during a head manufacturing process, the recording magnetic field changes, which involves the variation of the track width to be recorded on the medium. In accordance with an embodiment of the present invention, the main magnetic pole of a magnetic head includes a track-defining section shaped in trapezoid and a magnetic flux guiding section formed in trapezoid, as viewed from above. The track-defining section is formed such that its width parallel to the air bearing surface (ABS) increases at the rate of 10 to 20% with respect to its height-direction length. The rate of 10 to 20% is a range in which the shape is properly controllable taking into account the variations resulting from the tolerance of the head manufacturing process.

Magnetic head main pole with leading and trailing edges of different lengths and progessively increasing cross-sectional area in a height-direction

In one embodiment, a seed layer, an underlayer, and a magnetic domain control layer are laminated on both sides of a magnetoresistive sheet unit. A lower electrode film is thinly formed on an upper portion of the magnetic domain control film. A portion of the lower electrode film near the magnetoresistive sheet unit does not protrude substantially from an upper surface of the magnetoresistive sheet unit. Should the portion protrude, a step from the upper surface of the magnetoresistive sheet unit is about 14 nm or less. This portion and the upper surface of the magnetoresistive sheet unit are formed into a flat surface. An upper electrode film is formed thickly on an upper portion of the lower electrode film on an outside thereof so as to circumvent the flat surface. A protective layer, an upper gap film, and an upper magnetic shield film are also formed.

Magnetoresistive head and fabricating method thereof, and read write separation type head

Making thinner the magnetic domain control layer deteriorates the magnetic properties. Also, disturbances tend to increase the magnetization dispersion of the magnetic domain control layer, thereby lowering the magnetic domain control bias magnetic field. In one embodiment of the invention, a first magnetic domain control layer is provided in the proximity of the free layer of the GMR sensor in such a way that the track width is Twr. Outside the first magnetic domain control layer is provided a second magnetic domain control layer. The second magnetic domain control layer placed outside the first magnetic domain control layer gives the first magnetic domain control layer an external bias field. The amount of magnetization of the tip of the first magnetic domain control layer is polarized and increased by the bias magnetic field from the second magnetic domain control layer. This causes the first magnetic domain control layer to apply a strong bias magnetic field having a lower dispersion to the free layer of the GMR sensor.

Magnetoresistive head, with second magnetic domain control layers and manufacturing method thereof

A magnetic domain control underlayer is formed below a magnetoresistive multi-layered film thereby bringing the magnetic domain control film into contact with both lateral end faces of a free layer and appropriate magnetic domain control can be attained in a state of minimizing a surplus bias magnetic field from the magnetic domain control film.

Magnetoresistive head having magnetic domain control film in contact with underlayer and with ends of free layer

In a magnetoresistive head according to the present invention, a magnetic domain control film formed at the end of a free layer of a stack of magnetoresistive layers is formed of a Co alloy film, and an underlayer controlling the crystallization state of the Co alloy film and an amorphous metal film layer for controlling the crystallization state of the underlayer are disposed below the magnetic domain control film.

Magnetoresistive sensor with random crystal orientation underlayer and magnetic domain control film center aligned with free layer

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Kanagawa, Japan

Norihiro Ookawa