Nec Corporation

Waseda University

Yamamoto-ms Co., Ltd.

Mikiko Saito

Tamaki Toba

Nobuyuki Ishiwata

Tsutomu Ishi

Hiroaki Honjo

Shinsaku Saito

Yoshihiro Nonaka

Keishi Ohashi

Tetsuya Osaka

Kazuhiko Hayashi

Kazuhiko Yamada

Yoshihiko Yasue

Fujio Suzuki

Hiroyuki Sato

Masahiro Yanagisawa

Takuya Nakanishi

Wataru Yamamoto

Takayuki Homma

Tomoyuki Yamamoto

Kimiko Koiwa

Naonobu Shimamoto

Yoshihino Nonaka

There is provided a novel optical sensor utilizing a surface plasmon resonance technique which is capable of detecting a substance to be detected with high sensitivity independently of a wavelength of irradiated light and is capable of obtaining information, other than a refraction index, on the substance to be detected. At the center of a surface of a metallic filmwhich is formed on a substrate and has no aperture, a circular depressionwith a diameter of 0.1 to 250 nm is formed and with the depressiondefined as a center, a plurality of depressionsare concentrically formed at intervals of 450 to 530 nm.

Optical sensor

A recording head is a magnetic head in which ends on one side of opposed first and second magnetic cores form a recording gap, said other ends form a magnetic joint, coils insulated by an insulating material are provided between said first and second magnetic cores, magnetic fluxes of said first and second magnetic cores excited by said coils leak from said recording gap so that recording onto a recording medium is carried out. In said recording head, a distance from said end of said recording gap close to said magnetic medium to a contact point of said magnetic joint (hereinafter, yoke length) is not more than 20 &#x3bc;m. A magnetic recording/reproduction apparatus has this head.

Recording head, recording head manufacturing method, combined head and magnetic recording/reproduction apparatus

By inserting a first antistripping layer comprising a first non-magnetic layerand a first conductive layerbetween a first magnetic layerand a magnetic separation layer, adhesion between the first conductive layerand the magnetic separation layeris improved to prevent the first magnetic layerfrom stripping. In addition, by inserting a second antistripping layer comprising a second non-magnetic layerand a second conductive layerbetween a second magnetic layerand a magnetic gap layer, adhesion between the second conductive layerand the magnetic gap layeris improved to prevent the second magnetic layerfrom stripping.

Magnetic head having an antistripping layer for preventing a magnetic layer from stripping

A recording head is a magnetic head in which ends on one side of opposed first and second magnetic cores form a recording gap, said other ends form a magnetic joint, coils insulated by an insulating material are provided between said first and second magnetic cores, magnetic fluxes of said first and second magnetic cores excited by said coils leak from said recording gap so that recording onto a recording medium is carried out. In said recording head, a distance from said end of said recording gap close to said magnetic medium to a contact point of said magnetic joint (hereinafter, yoke length) is not more than 20 &mgr;m. A magnetic recording/reproduction apparatus has this head.

By inserting a first antistripping layer comprising a first non-magnetic layer and a first conductive layer between a first magnetic layer and a magnetic separation layer adhesion between the first conductive layer and the magnetic separation layer is improved to prevent the first magnetic layer from stripping. In addition, by inserting a second antistripping layer comprising a second non-magnetic layer and a second conductive layer between a second magnetic layer and a magnetic gap layer adhesion between the second conductive layer and the magnetic gap layer is improved to prevent the second magnetic layer from stripping.

A magnetic material includes a main component expressed by a general formula CoNiFeX, wherein X is at least one element selected from the group consisting of Cr, Ti, V, Ru, Rh, Pd, Os, Ir and Pt, and wherein weight percentages a, b, c and d of Co, Ni, Fe and X contents, respectively, in the main component are such that 40%&lE;a&lE;10%, 5%&lE;b&lE;20%, 10%&lE;c&lE;30%, and 0%<d&lE;10%.

Magnetic material having a high saturation magnetic flux density and a low coercive force

A magnetic head and a manufacturing method of the magnetic head and a magnetic recording and reproducing apparatus used this head, in which the following problem is solved, are provided. A plated film realizing large saturation magnetization Bs about 2T can not realize a high resistivity at the same time, therefore, when this plated film is applied to a magnetic head, the high frequency characteristic is deteriorated. This problem is solved at the present invention. Further, the present invention provides a magnetic head that is low cost and has large saturation magnetization Bs, and has a excellent high frequency characteristic suitable for a high density recording. A magnetic head, in which a coil insulated by insulation layers is disposed between a first magnetic core for recording and a second magnetic core for recording that is disposed to face the first magnetic core for recording via a recording gap, and which executes recording by that a magnetic flux of the first and second magnetic cores for recording excited by the coil is generated from the recording gap, is provided. And at least one of the first and second magnetic cores for recording is composed of a first plated magnetic layer and a second plated magnetic layer in a state that the first plated magnetic layer is disposed at the near side of the recording gap, and saturation magnetization of the first plated magnetic layer is 1.7 T (tesla) or more. And when resistivity of the first plated magnetic layer is defined as &rgr; and the thickness of the first plated magnetic layer is defined as &dgr; , and resistivity of the second plated magnetic layer is defined as &rgr; , and the thickness of the second plated magnetic layer is defined as &dgr; , and &dgr;

Magnetic head and manufacturing method thereof and magnetic recording and reproducing apparatus

A magnetic material includes a main component expressed by a general formula CoNiFeX, wherein X is at least one element selected from the group consisting of Cr, TI, V, Ru, Rh, Os, Ir and Pt, and wherein weight percentages a, b, c and d of Co, Ni, Fe and X contents, respectively, in the main component are such that 40%&lE;a&lE;75%, 5%&lE;b&lE;20%, 10%&lE;c&lE;30%, and 0%&lE;d&lE;10%.

A Co&mdash;Fe&mdash;Ni magnetic film has a composition represented by a chemical formula of Co Fe Ni (50&lE;x&lE;80, 20&lE;y&lE;40, and 3&lE;z<10 (wt %)) and has an average grain size not greater than 40 nm. The Co&mdash;Fe&mdash;Ni magnetic film is prepared by electroplating. A magnetic head comprises the magnetic film as a magnetic pole layer. A magnetic memory device comprises a combination of the magnetic head and a magnetic recording medium having a high coercive force between 3500 and 7000 Oe, both inclusive.

Co-Fe-Ni magnetic film having a high saturation magnetic flux density, composite thin film magnetic head using the film and magnetic memory device using the head

Disclosed is a magnetic heads suitable for high density recording which comprises an ID head where a CoNiFe film or a CoNiFeX film is formed by a physical vapor deposition method and further a plated film of CoNiFe etc. is formed while avoiding vanishment of a seed layer. The ID head shows high reliability and high production efficiency. The upper magnetic pole of the ID head is composed of a laminated layers of a first magnetic layer of a CoNiFe film or a CoNiFeX film which is formed by a physical vapor deposition method, a second magnetic layer of NiFe layer composing a seed layer laminated thereon, and a third magnetic layer of CoNiFe plated film etc. further laminated on the second layer.

Magnetic head, method for making the same and magnetic recording/reproducing device using the same

A magneto-resistive (MR) head having a read element including two magnetic shield films, two magnetic gap films which separate the two magnetic shield films and which are held between the two magnetic shield films, and an MR element held between the two magnetic gap films, with the two magnetic gap films having a stress value of up to 200 MPa.

Manufacturing process for a magneto-resistive head accommodating a narrow gap

A thin Co--Fe--Ni magnetic film comprising from 40% to 70% by weight of cobalt, from 20% to 40% by weight of iron, and from 10% to 20% of nickel, and having a crystal structure of a mixed crystal with an .alpha. phase of a body-centered cubic structure and a .gamma. phase of a face-centered cubic structure.

Co-Fe-Ni thin magnetic film, process for producing the same, composite

A thin film magnetic head is capable of providing sufficient characteristics as an interlayer insulation layer even when a low temperature heat treatment is performed, and improving throughput of a process. The thin film magnetic head is fabricated by forming a protective layer 2 on a substrate 1, forming a lower shield 3 on the protective layer 2, forming a reading MR portion 4 on the lower shield 3, and forming an insulation layer 5 as a gap layer. A soft magnetic material layer of permalloy is formed as a common pole 6. On the common pole 6, a negative type photoresist 7 is applied. A patterning is performed by irradiating a light via an insulation layer pattern mask 9 and performing etching by a developer. Then, heat treatment is performed at a temperature lower than or equal to 200.degree. C. under inert atmosphere to form an interlayer insulation layer. Over this, a coil 8 is formed. In order to save a step, a negative type photoresist 7 is applied to form an interlayer insulation layer.

Growing community of inventors

Tokyo, Japan

Mikiko Saito