Abstract: A magnetic sensor device comprises a magnetic sensor chip that has a substantially rectangular shape and that contains a magnetic sensor element; and a sealing body, which is composed of a resin material containing magnetic particles and that integrally seals the chip. The chip includes a first and second side surfaces which are mutually opposite to each other, and a third and fourth side surfaces which are mutually opposite to each other and orthogonal to the first and second side surfaces. The sealing body contains first to forth sealing parts. The thicknesses of the first and second sealing parts are smaller than the particle diameter of the particles, and the thickness of at least the third sealing part is larger than the particle diameter of the particles. The particles exist in at least the third sealing part and substantially do not exist in the first and second sealing parts.

Abstract: A magnetic sensor device comprises a magnetic sensor chip that has a substantially rectangular shape and that contains a magnetic sensor element; and a sealing body, which is composed of a resin material containing magnetic particles and that integrally seals the chip. The chip includes a first and second side surfaces which are mutually opposite to each other, and a third and fourth side surfaces which are mutually opposite to each other and orthogonal to the first and second side surfaces. The sealing body contains first to forth sealing parts. The thicknesses of the first and second sealing parts are smaller than the particle diameter of the particles, and the thickness of at least the third sealing part is larger than the particle diameter of the particles. The particles exist in at least the third sealing part and substantially do not exist in the first and second sealing parts.

Abstract: A manufacturing method for a magnetic head forms a leading shield having a top surface. The top surface of the leading shield includes first and second portions. The second portion is located farther from a medium facing surface than is the first portion, and recessed from the first portion. A first gap layer is then formed on the first portion. Then, a magnetic layer including an initial first side shield, an initial second side shield and a coupling section connecting them is formed using a mold. The mold is then removed. The coupling section is then removed by etching the magnetic layer. A second gap layer and a main pole are then formed in this order.

Abstract: A manufacturing method for a magnetic head forms a leading shield having a top surface. The top surface of the leading shield includes first and second portions. The second portion is located farther from a medium facing surface than is the first portion, and recessed from the first portion. A first gap layer is then formed on the first portion. Then, a magnetic layer including an initial first side shield, an initial second side shield and a coupling section connecting them is formed using a mold. The mold is then removed. The coupling section is then removed by etching the magnetic layer. A second gap layer and a main pole are then formed in this order.

Abstract: A thin-film magnetic head includes a slider substrate and a write element. The slider substrate has an air bearing surface at one side thereof. The write element has a recording magnetic pole film. The recording magnetic pole film is disposed on a plane crossing the air bearing surface over the slider substrate and has a large-width portion and a small-width portion continuously arranged in the named order toward the air bearing surface. The small-width portion has a smaller width than the large-width portion. Of the large-width portion and the small-width portion, at least the small-width portion has a first portion and a second portion. The second portion is continuous with an upper end of the first portion and has both side faces inclined in such a direction as to increase the width. An external angle of the first portion formed by a plane parallel to a bottom face and the side face is larger than an external angle of the second portion formed by a plane parallel to the bottom face and the side face.

Abstract: A method for manufacturing a thin-film magnetic head includes processes of forming a polishing position sensor and a recording head portion alongside on one side of a wafer. The process of forming the recording head portion has a step of performing a photolithography process after applying an alkali soluble resin film and a photoresist film in the named order. The process of forming the polishing position sensor has a step of performing a photolithography process on the photoresist film while having only the photoresist film out of the alkali soluble resin film and the photoresist film.

Abstract: A thin-film magnetic head includes a slider substrate and a write element. The slider substrate has an air bearing surface at one side thereof. The write element has a recording magnetic pole film. The recording magnetic pole film is disposed on a plane crossing the air bearing surface over the slider substrate and has a large-width portion and a small-width portion continuously arranged in the named order toward the air bearing surface. The small-width portion has a smaller width than the large-width portion. Of the large-width portion and the small-width portion, at least the small-width portion has a first portion and a second portion. The second portion is continuous with an upper end of the first portion and has both side faces inclined in such a direction as to increase the width. An external angle of the first portion formed by a plane parallel to a bottom face and the side face is larger than an external angle of the second portion formed by a plane parallel to the bottom face and the side face.

Abstract: A method of forming a magnetic pole section of a perpendicular magnetic recording type thin-film magnetic head and a method of manufacturing a perpendicular magnetic recording type thin-film magnetic head that include forming on an under layer a resist pattern having an opening, forming a first nonmagnetic layer, forming a first magnetic layer forming a magnetic layer pattern, removing the resist pattern and then applying a resist layer onto a first nonmagnetic layer and a magnetic layer pattern, developing or ashing partway the applied resist layer and baking the remaining resist layer, removing the first nonmagnetic layer from at least a side surface of the magnetic layer pattern by etching with the baked resist layer being left, removing all of the resist layer and then forming a second nonmagnetic layer on at least the magnetic layer pattern, and forming a second magnetic layer on the formed second nonmagnetic layer.

Abstract: A magnetic head incorporates: a medium facing surface; a coil; a pole layer; first and second shields disposed to sandwich the pole layer therebetween; a first gap layer disposed between the first shield and the pole layer; a second gap layer disposed between the second shield and the pole layer; and a substrate. The first shield is located closer to the substrate than the second shield. The magnetic head further incorporates an antireflection film disposed between the first shield and the first gap layer or between the first gap layer and the pole layer. The pole layer is formed by frame plating.

Abstract: A magnetic pole of a magnetic head includes a narrow and a wide portion, and is formed of a plating film. An electrode film forms the plating film, and is provided only under at least a part of the wide portion. A manufacturing method for the magnetic head includes: forming a plating-film-accommodating layer with an accommodating groove; forming the electrode film in part of the accommodating groove; and forming the plating film in the accommodating groove by plating using the electrode film. The accommodating groove includes a narrow and a wide groove portion for accommodating the narrow and wide portions, respectively. The electrode film is provided only in at least a part of the wide groove portion. In the step of forming the plating film, the plating film grows from the surface of the electrode film, and the narrow groove portion is filled with a part of the plating film.

Abstract: A manufacturing method for a magnetic head includes the steps of: forming a structure on a lower shield, the structure including a lower gap, a main magnetic pole and first and second side gaps; forming first and second side shields; forming an upper gap; and forming an upper shield. In the step of forming the structure, an initial lower gap layer is formed on the lower shield, the initial lower gap layer including a pre-lower-gap portion, and two to-be-removed portions that are located on opposite sides of the pre-lower-gap portion. Then, a protrusion including the main magnetic pole and the first and second side gaps is formed on the pre-lower-gap portion. With the top surface of the protrusion covered with a mask, the initial lower gap layer is etched in part to thereby form the lower gap.

Abstract: A testing method of a wafer provided with a plurality of thin-film magnetic heads is provided. Each of the plurality of thin-film magnetic heads includes a main pole layer, a first test pad formed on the wafer and electrically connected with an extended top end section of the main pole layer and a second test pad formed on the wafer and electrically connected with a back end section of the main pole layer. The testing method includes a step of measuring an electrical resistance between the first test pad and the second test pad, a step of judging whether the measured electrical resistance is within a set range, and a step of discriminating that the thin-film magnetic head is a non-defective product when the measured electrical resistance is within the set range.

Abstract: A method of forming a magnetic pole section of a perpendicular magnetic recording type thin-film magnetic head and a method of manufacturing a perpendicular magnetic recording type thin-film magnetic head that include forming on an under layer a resist pattern having an opening, forming a first nonmagnetic layer, forming a first magnetic layer, forming a magnetic layer pattern, removing the resist pattern and then applying a resist layer onto a first nonmagnetic layer and a magnetic layer pattern, developing or ashing partway the applied resist layer and baking the remaining resist layer, removing the first nonmagnetic layer from at least a side surface of the magnetic layer pattern by etching with the baked resist layer being left, removing all of the resist layer and then forming a second nonmagnetic layer on at least the magnetic layer pattern, and forming a second magnetic layer on the formed second nonmagnetic layer.

Abstract: A perpendicular recording thin-film magnetic head comprises a main magnetic pole having a tip main magnetic pole part extending in a height direction from a medium-opposing surface and a base main magnetic pole part connected to the tip main magnetic pole part on a side opposite from the medium-opposing surface side and wider than the tip main magnetic pole part in a track width direction; a return yoke extending in the height direction from the medium-opposing surface and magnetically coupling with the base main magnetic pole part at a position distanced from the medium-opposing surface in the height direction, while opposing the tip main magnetic pole part through a write gap layer in a bit length direction in the medium-opposing surface; and a main magnetic pole adjacent magnetic shield layer extending along at least part of side faces of the main magnetic pole other than the medium-opposing surface as seen in a laminating direction, while holding a nonmagnetic layer between the main magnetic pole and the

Abstract: A magnetic head incorporates: a medium facing surface; a coil; a pole layer; first and second shields disposed to sandwich the pole layer therebetween; a first gap layer disposed between the first shield and the pole layer; a second gap layer disposed between the second shield and the pole layer; and a substrate. The first shield is located closer to the substrate than the second shield. The first shield has a first layer and a second layer disposed between the first layer and the first gap layer.

Abstract: A magnetic pole of a magnetic head includes a narrow and a wide portion, and is formed of a plating film. An electrode film forms the plating film, and is provided only under at least a part of the wide portion. A manufacturing method for the magnetic head includes: forming a plating-film-accommodating layer with an accommodating groove; forming the electrode film in part of the accommodating groove; and forming the plating film in the accommodating groove by plating using the electrode film. The accommodating groove includes a narrow and a wide groove portion for accommodating the narrow and wide portions, respectively. The electrode film is provided in at least a part of the wide groove portion. In the step of forming the plating film, the plating film grows from the surface of the electrode film, and the narrow groove portion is filled with a part of the plating film.

Abstract: A manufacturing method for a magnetic head includes the steps of; forming a structure on a lower shield, the structure including a lower gap, a main magnetic pole and first and second side gaps; forming first and second side shields; forming an upper gap; and forming an upper shield. In the step of forming the structure, an initial lower gap layer is formed on the lower shield, the initial lower gap layer including a pre-lower-gap portion, and two to-be-removed portions that are located on opposite sides of the pre-lower-gap portion. Then, a protrusion including the main magnetic pole and the first and second side gaps is formed on the pre-lower-gap portion. With the top surface of the protrusion covered with a mask, the initial lower gap layer is etched in part to thereby form the lower gap.

Abstract: A magnetic head includes: a coil; a pole layer; a shield having an end face located in a medium facing surface forward of an end face of the pole layer along a direction of travel of a recording medium; a gap layer between the shield and the pole layer; and a substrate on which the foregoing elements are stacked. The top surface of the pole layer includes: first and second portions with a difference in height therebetween; and a third portion connecting the first and second portions to each other. The first portion has an edge located in the medium facing surface, and the second portion is located farther from the medium facing surface and from the substrate than the first portion. The magnetic head further includes a nonmagnetic layer disposed between the second portion and the gap layer. The nonmagnetic layer has a surface touching the second portion, the surface having an edge located at the boundary between the second and third portions.

Abstract: A testing method of a wafer provided with a plurality of thin-film magnetic heads is provided. Each of the plurality of thin-film magnetic heads includes a main pole layer, a first test pad formed on the wafer and electrically connected with an extended top end section of the main pole layer and a second test pad formed on the wafer and electrically connected with a back end section of the main pole layer. The testing method includes a step of measuring an electrical resistance between the first test pad and the second test pad, a step of judging whether the measured electrical resistance is within a set range, and a step of discriminating that the thin-film magnetic head is a non-defective product when the measured electrical resistance is within the set range.

Abstract: A thin-film magnetic head includes a first magnetic layer, a flat, spiral-shaped coil, a toroidal-shaped insulating layer covering the coil, and a second magnetic layer touching the insulating layer and disposed to sandwich part of the coil between itself and the first magnetic layer. The second magnetic layer has a recessed portion that enters a space inside the insulating layer. In the recessed portion, the bottom surface of the second magnetic layer includes a first flat portion a part of which touches the top surface of the first magnetic layer, while the top surface of the second magnetic layer includes a second flat portion located in the space and substantially parallel to the first flat portion. In a cross section that divides each of the first and second magnetic layers into two equal portions, the second flat portion is 0.