Alps Electric Co., Ltd.

Tdk Corporation

Alps Electric Company Co., Ltd.

Yoshihiro Kanada

Hisayuki Yazawa

Mitsuo Kawasaki

Mitsuhiro Gotoh

Kiyoshi Sato

Kiyoshi Kobayashi

Akihiro Makino

Eiji Umetsu

Toshinori Watanabe

Takashi Hatanai

Fumihito Koike

Akira Takahashi

Nobuhiro Hayashi

Naruaki Oki

Naoki Sakatsume

Akira Koyama

Hiromi Ikegami, Legal Representative

Chiaki Ikegami, Legal Representative

Hiroaki Nakajima

The upper magnetic pole layer and/or lower magnetic pole layer comprises a soft magnetic film having a variable region in which the chemical composition of Fe changes in the direction of thickness in at least a part thereof, and the difference of the proportions of Fe between the regions most abundant in Fe and most deficient in Fe is 4% by mass or more in the variable region. The structure of the soft magnetic film permits the saturation magnetic flux density Bs to be improved while decreasing the coercive force Hc by forming fine crystal grains, thereby enabling a thin film magnetic head excellent in high density recording to be manufactured.

Soft magnetic film and thin film magnetic head using soft magnetic film, process for manufacturing soft magnetic film and process for manufacturing thin film magnetic head

A soft magnetic film is formed of a CoFe alloy having an Fe content in the range of 68 to 80 mass %, thereby having a saturation magnetic flux density of 2.0 T or more. The center lain average roughness of the film surface is 9 nm or less. The soft magnetic film can achieve a corrosive resistant magnetic head with a high recording density.

Method of manufacturing a thin-film magnetic head using a soft magnetic film having high saturation magnetic flux density

A soft magnetic film of the present invention is a plated film composed of Co and Fe, and columnar crystals extending in the film thickness direction are provided. In the present invention, columnar crystals extending in the film thickness direction are provided so that an improvement in the surface roughness of the film surface and an improvement in the corrosion resistance can be achieved. Furthermore, the saturation magnetic flux density Bs can also be improved by making the crystal fine and eliminating the need for addition of the noble metal element. That is, according to a CoFe alloy of the present invention, both the corrosion resistance and the saturation magnetic flux density Bs can be improved, and specifically, the above-mentioned saturation magnetic flux density Bs can be increased to 2.35 T or more.

Magnetic film and thin film magnetic head using this magnetic film

A gap of a thin-film magnetic head is formed of NiP. The P content of the NiP gap layer is controlled to be within the range of 11 mass percent to 14 mass percent so that the gap layer is nonmagnetic.

Thin-film magnetic head having magnetic gap formed of NiP

A lower magnetic pole layer and/or an upper magnetic pole layer are formed of a CoFe&#x3b1; alloy in which the component ratio X of Co is 8 to 48 mass %, the component ratio Y of Fe is 50 to 90 mass %, the component ratio Z of the element &#x3b1; (the element &#x3b1; is at least one of Ni and Cr) is 2 to 20 mass %, and the equation X+Y+Z=100 mass % is satisfied. Consequently, the saturated magnetic flux density can be 2.0 T or more, and a thin-film magnetic head have a higher recording density can be manufactured

Soft magnetic film having improved saturated magnetic flux density, magnetic head using the same, and manufacturing method therefore

A soft magnetic film composed of an alloy represented by the formula FeNiRe is used for forming a lower core layer and/or an upper core layer. Since having a high saturated magnetic flux density, a high resistivity, superior corrosion resistance, and a small loss in a high frequency signal region, the FeNiRe alloy can be used for forming a highly reliable thin film magnetic head.

FeNiRe soft magnetic film and thin film magnetic head using the same for simultaneous adjustment of resistivity and saturated magnetic flux density

A soft magnetic film comprising an FeCo alloy containing noble metals such as Pr and Rh. This soft magnetic film has a saturation magnetic flux density Bs of at least 2.0 and high corrosion resistance. This soft magnetic film may be included in a thin-film magnetic head. A lower magnetic pole layer or an upper magnetic pole layer of the thin-film magnetic head has a composition represented by the formula FeCo&#x3b1;, wherein &#x3b1; is at least one element selected from the group consisting of Pd, Pt, Ru, and Ir, and wherein the ratio X/Y by mass percent of Fe to Co is in the range of 2 to 5, the &#x3b1; content Z is in the range of 0.5 to 18 mass percent, and X+Y+Z=100 mass percent.

Soft magnetic film having saturation magnetic flux density Bs of at least 2.0 T and magnetic head including the same

A gap depth determining insulating layer is formed on a lower core layer. A curved face is formed on a front edge face of the gap depth determining insulating layer so as to gradually depart from an ABS surface from the bottom at the lower core layer to the top of the curved face. A back end of an upper magnetic layer can be formed on the gap depth determining insulating layer, whereby the volume of the upper magnetic layer can be increased while a gap depth is maintained at a predetermined length.

Thin-film magnetic head having a high recording density and frequency

A soft magnetic film is formed which is represented by the formula (FeNi)Mo, in which 0.65&#x2266;x&#x2266;0.75 and x+y=1 are satisfied when x and y are on a mass percent ratio basis, and 0&#x3c;b&#x2266;5 and a+b=100 are satisfied when a and b are on a mass percent basis, and by using this soft magnetic film, a lower core layer and/or an upper core layer is formed. Accordingly, a saturated magnetic flux density of 1.6 T or more and a resistivity of 40 &#x3bc;&#x3a9;&#xb7;cm or more can be obtained, and hence a thin film magnetic head having a small loss in a high frequency signal region can be provided.

Soft magnetic film and thin film magnetic head using the same

A gap layer of a thin-film magnetic head is formed of NiP. The P content of the NiP gap layer is controlled to be within the range of 11 mass percent to 14 mass percent so that the gap layer is nonmagnetic.

A magnetic head includes an upper magnetic pole layer formed by electroplating in which the density of the impressed current is increased in stages every predetermined period of time. The upper magnetic pole layer contains at least 60 mass % of Fe. The difference between the maximum Fe content and the minimum Fe content of the upper magnetic pole layer within 0.3 &#x3bc;m from the interface with the gap layer is 6 mass % or less.

Magnetic head with magnetic pole minimum Fe content difference and Fe content increasing toward interface with gap layer

A lower pole layer and/or an upper pole layer is formed by plating a soft magnetic film represented by the formula FeNi&#x3b1;(wherein element &#x3b1; is at least one of Tc, Ru, Rh, Pd, Re, Os, Ir and Pt), wherein the composition ratio X of Fe is 65% by mass to 74% by mass, the composition ratio Y of Ni 25% by mass to 34% by mass, the composition ratio Z of the element &#x3b1; is 1% by mass to 7% by mass, and X+Y+Z=100% by mass. Therefore, a thin film magnetic head adaptable to a higher recording density and having excellent corrosion resistance can be manufactured.

Corrosion-resistant soft magnetic film, method of producing the same, thin film magnetic head using the same and method of manufacturing the thin film magnetic head

A lower pole layer and/or an upper pole layer is formed by plating a NiFe alloy having a Fe composition ratio of 76% by mass to 90% by mass, or having an average crystal grain diameter of 130 &angst; to 175 &angst; and a Fe composition ratio of 70% by mass to 90% by mass. As a result, the saturation magnetic flux density can be increased to 1.9 T or more, and a thin film magnetic head excellent for a higher recording density can be manufactured.

Soft magnetic film having high saturation magnetic flux density, thin film magnetic head using the same, and methods of producing the soft magnetic film and the thin film magnetic head

Soft magnetic film having high saturation magnetic flux density, thin-film magnetic head using the same, and manufacturing method of the same

A soft magnetic film has a composition represented by the formula Fe Co &agr; wherein &agr; is at least one element selected from the group consisting of Rh, Pd, Pt, Ru, and Ir and X&plus;Y&plus;Z&equals;100 mass percent. The ratio X/Y by mass percent of Fe to Co is in the range of 2 to 5, and the &agr; content Z is in the range of 0.5 to 18 mass percent. This alloy exhibits a saturation magnetic flux density of at least 2.0 T and high corrosion resistance.

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Niigata-ken, Japan

Yoshihiro Kanada