Abstract: A lower magnetic pole layer and/or an upper magnetic pole layer are formed of a CoFe&agr; 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 &agr; (the element &agr; 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.

Abstract: 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.

Abstract: A soft magnetic film is formed which is represented by the formula (FexNiy)aMob, in which 0.65≦x≦0.75 and x+y=1 are satisfied when x and y are on a mass percent ratio basis, and 0<b≦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 &mgr;&OHgr;·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.

Abstract: 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.

Abstract: 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.

Abstract: A soft magnetic film of the invention is to improve a resistivity &rgr; while maintaining a coercive force Hc and a saturation magnetic flux density Ms in good states by adding an element X (X is one or more kinds of elements selected from O, C, N, and S). Further, a thin film magnetic head capable of coping with an increase in a recording density and an increase in a recording frequency can be provided by using the soft magnetic film in core layers.

Abstract: 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 FeXCoY&agr;Z, wherein &agr; 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 &agr; content Z is in the range of 0.5 to 18 mass percent, and X+Y+Z=100 mass percent.

Abstract: A gap layer is formed by electroplating NiP using a pulsed current. This can suppress crystallization of Ni due to epitaxial growth near the interface of the gap layer. Therefore, a large amount of nonmagnetic element such as P can be contained, and the vicinity of the interface can be put into an amorphous state to improve corrosion resistance.

Abstract: A thin-film magnetic write head includes a lower core layer composed of a magnetic material and an upper core layer composed of a magnetic material. The upper core layer is opposed to the lower core layer with a nonmagnetic gap layer therebetween at a surface facing a recording medium. The thin-film magnetic write head writes data to be read by a thin-film magnetic read head, which has a track width Tr and a distance H2 between an upper shielding layer and a lower shielding layer. The length in the track width direction at a magnetic contact between the gap layer and the upper core layer is 1 &mgr;m or less. The formula A≦H1−H2 is satisfied A is a difference between the height of the upper surface of the gap layer on a center line in the track width direction and the height of the upper surface of the gap layer at a distance Tr/2 from the center line in the track width direction. H1 is a gap length of the gap layer.

Abstract: 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.

Abstract: 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 &mgr;m from the interface with the gap layer is 6 mass % or less.

Abstract: 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 Å to 175 Å 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.

Abstract: A lower magnetic pole layer and/or an upper magnetic pole layer are formed of a CoFe&agr; 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 &agr; (the element &agr; 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.

Abstract: A soft magnetic film has a composition represented by the formula FeXCoY&agr;Z wherein &agr; is at least one element selected from the group consisting of Rh, Pd, Pt, Ru, and Ir and X+Y+Z=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.

Abstract: 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.

Abstract: A NiFe alloy film is formed by an electroplating process using a pulsed direct current. The resulting NiFe alloy has an average crystal grain size of not more 105 Å and an Fe content in a range of 60 percent by weight to 75 percent by weight. The NiFe alloy film exhibits a high saturation magnetic flux density and a low coercive force. A thin-film magnetic head having a lower core layer and/or an upper core layer composed of the NiFe alloy film is suitable for higher recording densities.

Abstract: A lower core layer and upper core layer are conventionally made of a CoFeNi alloy or the like having a relatively high saturation magnetic flux density, but these layers have the problem of increasing an eddy current loss due to the low resistivity of the CoFeNi alloy with a higher recording frequency. In the present invention, a lower core layer and/or upper core layer is made of a CoFeNiX (X is S, P, or the like) alloy, which has a high saturation magnetic flux density, high resistivity, and low coercive force, as compared with the CoFeNi alloy. Therefore, it is possible to manufacture a thin film magnetic head capable of complying increases in recording density and recording frequency in the future.

Abstract: A gap layer is formed by electroplating NiP using a pulsed current. This can suppress crystallization of Ni due to epitaxial growth near the interface of the gap layer. Therefore, a large amount of nonmagnetic element such as P can be contained, and the vicinity of the interface can be put into an amorphous state to improve corrosion resistance.

Abstract: A thin film magnetic head includes an upper core layer and a lower core layer which are made of an Fe—M—O alloy, an Fe—M—T—O alloy or an NI—Fe—X alloy so that the upper core layer has a high saturation magnetic flux density, low coercive force and high resistivity, and the lower core layer has a lower saturation magnetic flux density than the upper core layer, low coercive force, high resistivity, and a low magnetostriction constant. Also the lower core layer is formed so that the thickness gradually decreases toward both side ends, and a gap layer can be formed on the lower core layer to have a uniform thickness. Since the lower core layer is formed by sputtering, a material having excellent soft magnetic material can be used, thereby enabling recording at high frequency.

Abstract: A lower pole layer and/or an upper pole layer is formed by plating a soft magnetic film represented by the formula FeXNiY&agr;Z (wherein element &agr; 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 &agr; 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.