Fujitsu Corporation

Ikuya Tagawa

Yuji Uehara

Tomoko Kutsuzawa

Minoru Hasegawa

Yoshinori Ohtsuka

Syuji Nishida

Hiroshi Maeda

Yukinori Ikegawa

Masahiro Kakehi

Takashi Sekikawa

Shoji Ikeda

Kenichiro Yamada

Yoshinori Otsuka

Koji Matsumoto

Takayuki Kubomiya

Teruo Kiyomiya

Hideo Niwa

Hiroki Fujimoto

Naoki Takeguchi

According to the present invention, a recording magnetic head suitable for increasing a surface recording density and having a large recording magnetic field and a small recording blur is provided. A lower magnetic pole layer and an upper magnetic pole layer opposing the lower magnetic pole layer are formed, and a lower sub magnetic pole composed of a plurality of magnetic layers is formed along a medium facing face on the lower magnetic pole layer. The lengths in a direction perpendicular to the medium facing face of the respective magnetic layers forming the lower sub magnetic pole are longer as the respective magnetic layers get further away from the upper magnetic pole layer.

Recording magnetic head and magnetic storage device using the same

A soft magnetic film includes a ferromagnetic layer. The ferromagnetic layer is laid over a non-magnetic substructure including ferromagnetic atoms. The uniaxial magnetic anisotropy may be established in the ferromagnetic layer. Since a magnetic property is not required in the substructure under the ferromagnetic layer, the soft magnetic film of this type may be utilized for purposes of wider variations.

Thin film head with nickel-iron alloy non-magnetic substratum between non-magnetic gap layer and upper magnetic pole layer

A magnetoresistive transducer includes a magnetoresistive (MR) film interposed between domain control layers along the surface of a lower non-magnetic gap layer. Lead layers are formed on the domain control layers. An upper non-magnetic gap layer and an upper shield layer are sequentially formed to extend over the MR film and the lead layers. The upper shield layer is opposed to the surfaces of the MR element and the lead layers at a flat boundary or interface. The residual magnetization is supposed to exist in the upper shield layer in the direction of the magnetization established in the domain control layers after the upper shield layer has been subjected to the applied magnetic field for the magnetization of the domain control layers. The residual magnetization can be kept continuous along the flat interface of the upper shield layer. Any magnetic poles are hardly generated along the interface of the upper shield layer. The longitudinal bias field can be prevented from receiving the interaction of the residual magnetization in the upper shield layer. Reduction in the longitudinal bias field can thus be suppressed.

Magnetoresistive transducer having stronger longitudinal bias field

A soft magnetic film comprising Fe, Co, a metallic element (M), and oxygen (O) is provided. The soft magnetic film is represented by a composition formula of (Fe Co ) M O . The metallic element (M) is one selected from a group consisting of Al, B, Ga, Si, Ge, Y, Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Rh, Ru, Ni, Pd and Pt, or is an alloy composed of at least two selected from this group. The composition formula fulfills the following conditions: a&equals;0.05-0.65; y&equals;0.2-9 at %, z&equals;1-12 at %, and y&plus;z&equals;<15 at %; and x&equals;(100&minus;y&minus;z) at %. A crystal structure is formed by having a bcc phase as a principal phase. The bcc phase has a crystal grain not exceeding 50 nm in diameter. The bcc phase includes a solid solution of the metallic element (M) and the oxygen (O).

Soft magnetic film of FeCoMO having a high saturation flux density, a moderate soft magnetism and a uniaxial magnetic anisotropy

An object of the present invention is to provide a recording head having a magnetic pole simultaneously possessing a high saturation magnetic flux density, a high permeability and a high electric resistivity, and the magnetic pole of the recording head is a polycrystalline film comprising Fe whose content is not less than 57.5 atomic % and not more than 94.5 atomic %; one or more kinds of elements selected from the element group of Al, B, Ga, Si, Ge, Y, Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W and Rh, whose whole content is not less than 1 atomic % and not more than 15 atomic %; N whose content is not less than 0.5 atomic % and not more than 10 atomic %; and O whose content is not less than 1.5 atomic % and not more than 22.5 atomic %.

Magnetic thin film, magnetic thin film forming method, and recording head

A liquid resist is introduced between adjacent conductive lines of a coil pattern girdling around a magnetic core piece. When the liquid resist is cured, an insulating resin filler can be fixed between the adjacent conductive lines of the coil pattern. An insulating metallic layer is formed to extend over the insulting resin filler and the conductive lines of the coil pattern. Thereafter, the insulating metallic layer is subjected to a flattening grinding treatment until at least a part of the conductive line is exposed at a flattened surface. Of the resist, of a higher fluidity, penetrates in every hole and corner between the adjacent conductive lines, the gap defined between the adjacent conductive lines is fully filled with the insulating material. No voids remain in the gap. The conductive line of the coil can be reliably prevented from corrosion or oxidation. Moreover, a relatively brittle of fragile insulating resin filler is reliably prevented from being subjected to the flattening.

Method of producing thin film magnetic head

A thin film magnetic head includes an upper and a lower magnetic pole layer extending forward from a central magnetic core within a thin film coil. A narrow upper and lower front magnetic pole piece are connected to the front ends of the upper and lower magnetic pole layer, respectively. The upper front magnetic pole piece extends rearward from its front end exposed at a medium-opposed surface. The lower front magnetic pole piece extends in a lateral direction along the medium-opposed surface by a lateral width larger than that of the upper front magnetic pole piece. The lower front magnetic pole piece extends rearward from the medium-opposed surface by a longitudinal length smaller than that of the upper front magnetic pole piece. The lower front magnetic pole piece serves to concentrate the magnetic flux at the front ends of the upper and lower front magnetic pole pieces. Since the lower front magnetic pole piece is designed to have a larger lateral width in the lateral direction irrespective of a smaller length in the longitudinal direction, the production of the lower front magnetic pole piece can remarkably be facilitated.

Thin film magnetic head with short lower magnetic pole piece

A magnetic recording medium stable against heat of which high density recording can be attained is provided by employing a magnetic material such that coercive magnetic force in a recording magnetic layer increases with temperature rise. The magnetic recording medium is one in which the recording magnetic layer in which magnetic recording is carried out comprises an N-type Ferrimagnetic material, and compensation temperature of this N-type Ferrimagnetic material is made to be higher than an operating temperature range in which the magnetic recording medium is used.

Magnetic recording medium and magnetic recording medium driver for the medium with N-type ferrimagnetic recording layer

A magnetic head has a lower sub-magnetic pole and an upper sub-magnetic pole disposed to be adjacent to a moving magnetic disk. The lower sub-magnetic pole and the upper sub-magnetic pole are placed adjacent one another with a predetermined interval at an adjacent point to the magnetic disk. A magnetic field is generated between those magnetic poles so that the magnetic disk is magnetized. A soft magnetic film extending between the magnetic poles and a first non-magnetic film and a second non-magnetic film supporting the soft magnetic film are disposed between the magnetic poles.

Magnetic head, method of manufacturing magnetic head and information recording apparatus

A thin film magnetic head includes an upper magnetic pole maintaining a constant thickness in a range determined by the so-called gap depth. A thinner film portion is defined in the upper magnetic pole in a range rearward of the range determined by the gap depth. The thinner film portion has a reduced thickness smaller than the constant thickness. The upper magnetic pole starts to enlarge the core width in the lateral direction at the rear end of the region determined by the so-called neck height. The neck height smaller than the gap depth serves to establish a reduction in the thickness of the upper magnetic pole after the upper magnetic pole gets larger in the lateral direction. A magnetic saturation can reliably be prevented at the thinner film portion in the upper magnetic pole. The front end of the upper magnetic pole is allowed to receive a larger quantity of a magnetic flux. It is possible to reliably enhance a magnetic field for recordation in the thin film magnetic head.

Thin film magnetic head

A liquid resist is introduced between adjacent conductive lines of a coil pattern girdling around a magnetic core piece. When the liquid resist is cured, an insulating resin filler can be fixed between the adjacent conductive lines of the coil pattern. An insulating metallic layer is formed to extend over the insulting resin filler and the conductive lines of the coil pattern. Thereafter, the insulating metallic layer is subjected to a flattening grinding treatment until at least a part of the conductive line is exposed at a flattened surface. Since the liquid of the resist, of a higher fluidity, penetrates in every hole and corner between the adjacent conductive lines, the gap defined between the adjacent conductive lines is fully filled with the insulating material. No voids remain in the gap. The conductive line of the coil can be reliably prevented from corrosion or oxidation. Moreover, a relatively brittle of fragile insulating resin filler is reliably prevented from being subjected to the flattening grinding treatment.

Thin film magnetic head including a coil insulating resin filler and an insulating metallic layer covering at least partly the insulating resin filler on a datum plane

There is provided a magnetic head which is able to enhance the magnetic field intensity to be generated by shaping a magnetic pole, and a method of manufacturing the same. The method of manufacturing a magnetic head, comprising the steps of forming a lower recording magnetic pole and an upper recording magnetic pole, and trimming partially an elongated pole in the vicinity of a floating surface of the upper recording magnetic pole and an upper portion of the lower recording magnetic pole positioned below and around the elongated pole by an ion milling method, wherein a core width of the elongated pole can be adjusted.

Magnetic head and method of manufacturing the same

An information recording device which records information at a high recording density such that an error rate is reduced. In particular, an information recording device that includes a recording head, arranged near or to be close to the recording medium, for applying magnetic fields to the small regions when the recording head relatively moves with respect to the recording medium to pass on the small regions of the recording medium, and a recording head controller for controlling the recording head to cause the recording head to apply magnetic fields to the small regions in a free region of the recording medium in a standby state in which at least information is not recorded on the recording medium to uniform the directions of magnetization of the small regions so as to erase the information in the predetermined free region.

Information recording device having a function of erasing information in a standby state

A spin valve head comprises a spin valve film having at least a pinned magnetic layer, a nonmagnetic metal layer, and a free magnetic layaer. The spin valve head further comprises a hard magnetic layer for controlling magnetic domains of the free magnetic layer, and electrode elements for supplying a sense current to the spin valve film, wherein the hard magnetic layer and the free magnetic layer are positioned not to overlap an orthographic projection of the hard magnetic layer in a thickness direction of the spin valve film with an orthographic projection of the free magnetic layer in the thickness direction of the spin valve film. According to such configuration, a single magnetic domain structure which does not generate a reverse magnetic field region throughout the overall surface of the free magnetic layer can be obtained, so that the hysteresis phenomenon is not caused in the spin valve head output. Therefore, the output with no noise can be derived.

Growing community of inventors

Kawasaki, Japan

Ikuya Tagawa