Abstract: A pole layer incorporate a track width defining and a wide portion. A material forming the pole layer is an alloy whose major elements are iron and nickel. In the alloy, where the proportions of iron and nickel with respect to the total of iron and nickel are indicated as (100-M) weight % and M weight %, respectively, M is greater than 0 and smaller than or equal to 10. The internal stress of the pole layer is a tensile stress. The magnetostriction constant of the material forming the pole layer is positive. Where the anisotropy field of the pole layer is Hk (A/m), the magnetostriction constant of the material forming the pole layer is ?(×10?6), and the internal stress of the pole layer is ? (MPa), the value of Hk/(?×?) is greater than 0.01 and smaller than 0.2.

Abstract: The invention provides a magnetic head for perpendicular magnetic recording having an air bearing surface positioned facing the recording surface of a recording medium, which records magnetic information on the recording medium by generating magnetic flux toward the recording surface of the recording medium, and comprises a magnetic pole which generates magnetic flux toward the recording surface of the recording medium and a return yoke having one end connected to the magnetic pole and the other end positioned facing the recording surface of the recording medium, wherein the material composing the magnetic pole has a magnetostriction constant ? of at least 0 and less than 10×10?6, with a parameter P represented by the formula: P=Hk/(?×?) (where Hk represents the magnetic anisotropic field (A/m), ? represents the stress (MPa) and ? represents the magnetostriction constant) of larger than 0.1 and less than 200.

Abstract: A main pole layer of a magnetic head includes a first portion disposed at a distance from a medium facing surface, and a second portion that is smaller in thickness than the first portion and disposed between the first portion and the medium facing surface. The step of forming the main pole layer includes the steps of forming a plating layer such that one of ends of the plating layer closer to the medium facing surface is located at a position that coincides with the position of one of ends of the first portion closer to the medium facing surface; forming a first nonmagnetic layer to cover the plating layer; polishing the first nonmagnetic layer and the plating layer; forming a space by removing the plating layer; forming a magnetic layer, which will be the main pole layer, in the space and on the top surface of the first nonmagnetic layer; forming a second nonmagnetic layer to cover the magnetic layer; and polishing the second nonmagnetic layer and the magnetic layer.

Abstract: Provided is a thin film magnetic head capable of ensuring the strength of a perpendicular magnetic field and improving recording performance. A bottom pole portion layer and a top pole portion layer constituting a part of a main magnetic pole are formed so that a cross sectional area of a complex including front end portions of the bottom pole portion layer and the top pole portion layer is smaller than a cross sectional area of a complex including rear end portions thereof, and a width of a top edge in an exposed surface is larger than a width of a bottom edge, and is equal to or larger than a width of the exposed surface in a middle position between the top edge and the bottom edge. In recording, magnetic fluxes flowing in a main magnetic pole are focused toward an air bearing surface, and are concentrated on the front end portion of the top pole portion layer which is a main emitting portion of the magnetic fluxes, so sufficient magnetic fluxes can be supplied to the air bearing surface.

Abstract: A thin-film magnetic head comprises: a first magnetic layer and a second magnetic layer each of which includes a magnetic pole portion, the first and second magnetic layers being magnetically coupled to each other at a distance from the medium facing surface ABS; a gap layer provided between the first and second magnetic layers; and a thin-film coil at least a part of which is disposed between the first and second magnetic layers. The second magnetic layer has a pole portion layer and a yoke portion layer. The pole portion layer has a saturated magnetic flux density equal to or greater than that of the yoke portion layer. The yoke portion layer includes: a first layer and a second layer, of which the first layer is in contact with the first magnetic layer and a surface of the pole portion layer that is closer to the gap layer; and the second layer is in contact with the first layer, the rear end surface of the pole portion layer and both side surfaces of the pole portion layer in the width direction.

Abstract: A manufacturing method in which a second magnetic layer of a thin-film magnetic head includes the steps of: forming a pole portion layer; forming a protective layer so as to cover a part of the pole portion layer located near the medium facing surface ABS; forming an electrode layer to be used as an electrode when forming a yoke portion layer by electroplating; forming the yoke portion layer by electroplating on the electrode layer using the electrode layer as an electrode; and removing an unnecessary portion of the electrode layer.

Abstract: A thin-film magnetic head comprises first and second magnetic layers; a gap layer provided between the first and second magnetic layers; a coupling portion for magnetically coupling the first magnetic layer and the second magnetic layer to each other at a distance from the medium facing surface ABS; and a thin-film coil at least part of which is disposed between the first and second magnetic layers. The second magnetic layer has a pole portion layer and a yoke portion layer. The pole portion layer has a saturated magnetic flux density equal to or greater than that of the yoke portion layer. The yoke portion layer magnetically connects the upper end of the coupling portion and the rear end surface of the pole portion layer to each other.

Abstract: The soft magnetic film takes its hard axis along the direction in which a magnetic field is generated and its easy axis along a direction perpendicular to the direction of the writer magnetic field. The magnetic bias film applies a magnetic bias along the easy axis to the soft magnetic film.

Abstract: A write head of a magnetic head for vertical magnetic recording comprises: a coil; a main pole layer that allows the magnetic flux corresponding to the magnetic field generated by the coil to pass therethrough and generates a write magnetic field; an auxiliary pole layer; a gap layer provided between the main pole layer and the auxiliary pole layer; and a yoke layer for magnetically coupling the main pole layer to the auxiliary pole layer. The main pole layer has a flat top surface. In the main pole layer the position in which the thickness starts to increase is located between the medium facing surface and the position in which the width starts to increase.

Abstract: Provided is a thin film magnetic head capable of securing recording characteristics even in the case where a return pole layer is disposed on a medium-outgoing side of the pole layer. The return yoke layer is disposed on a trailing side of the pole layer, and a neck height NH is within a range of NH≦W1 (a width of a front end portion in a main pole layer)+0.05 &mgr;m, and a height ratio (a ratio of the neck height NH to a throat height TH) NH/TH is within a range of 0.5<NH/TH<1.6. Thereby, the neck height NH and the height ratio NH/TH which have an influence on the recording characteristics can become appropriate, so even if the thickness of the gap layer is 0.2 &mgr;m or less to bring the return yoke layer closer to the pole layer, overwrite characteristics can be secured.

Abstract: The present invention provides a thin film magnetic head in which a magnetic domain structure of a magnetic pole layer is controlled and fluctuation in recording magnetization caused by leaked magnetic flux generated by unintentional shift of a magnetic domain wall can be prevented. When length of a front end portion which specifying a recording track width of a recording medium, in a magnetic pole part layer is set as D and width of an upper edge positioned on a medium outflow side of a magnetic pole end surface is set as W, a dimensional ratio D/W of the length D to the width W is set so as to lie within the range of 0<D/W≦2.3. Since magnetic domain stability of the magnetic pole part layer is assured on the basis of the proper formation of the shape of the front end portion, leak of magnetic flux from the front end portion immediately after recording is suppressed. Therefore, occurrence of an inconvenience such as unintended erasure of information caused by the leaked magnetic flux is prevented.

Abstract: A thin-film magnetic head comprises first and second magnetic layers, a gap layer provided between the first and second magnetic layers, and a thin-film coil at least a part of which is disposed between the first and second magnetic layers. The second magnetic layer has a pole portion layer, a yoke portion layer, and a coupling portion. The head further comprises a non-magnetic layer provided on a surface of the pole portion layer farther from the gap layer. The yoke portion layer interfaces with the rear end surface of the pole portion layer, and is greater than the pole portion layer in thickness in a cross section containing the interface.

Abstract: Provided is a thin film magnetic head capable of appropriately control the flow of magnetic flux from a yoke layer to a pole layer so as to prevent information from being overwritten without intention during recording. A perpendicular recording system thin film magnetic head is formed so that a portion of a yoke layer and a portion of a pole layer are connected to each other in a connecting surface. When a large amount of the magnetic flux contained in the yoke layer flows into the pole layer through the connecting surface, the large amount of the magnetic flux is concentrated in the connecting surface, so an excessive amount of the magnetic flux is not supplied to a front end portion of the pole layer, and an appropriate amount of the magnetic flux is supplied.

Abstract: A thin-film magnetic head comprises first and second magnetic layers, a gap layer provided between the first and second magnetic layers, and a thin-film coil at least a part of which is disposed between the first and second magnetic layers. The second magnetic layer has a pole portion layer, a yoke portion layer, and a coupling portion. The yoke portion layer is magnetically connected to the rear end surface of the pole portion layer and both side surfaces of the pole portion layer in the width direction. The rear end surface of the pole portion layer and the side surfaces of the pole portion layer in the width direction are each inclined relative to the direction perpendicular to the surface of the pole portion layer that faces the gap layer.

Abstract: A perpendicular magnetic recording apparatus includes a perpendicular double-layer film medium including a stack of a soft magnetic backing layer and a perpendicular magnetic recording layer in which recording is performed under a condition that a recording track pitch as a total of a recording track width and a guard-band width between recording tracks is set to be 1 &mgr;m or less, and a perpendicular magnetic recording head including a recording main pole, an auxiliary pole disposed at a gap having a length of five or less times the guard-band width with respect to the recording main pole, and an exciting coil.

Abstract: Provided is a thin film magnetic head which enables both ensuring overwrite characteristics and preventing an adverse effect resulting from side erase, such as degradation in an output signal. An exposed surface of a magnetic pole portion layer is configured to have the shape of an asymmetric inverted trapezoid corresponding to a remaining region which remains after removing a width increasing region in the shape of a right triangle from a rectangular region on the side of a side edge. The side edge of the exposed surface is caused to correspond to the side on which side erase occurs, more specifically the side on which a magnetic flux emitted from the magnetic pole portion layer onto a target track of a hard disk causes information to unintentionally overwrite existing information recorded on an adjacent track. This configuration allows preventing the exposed surface from extending to the adjacent track, thus preventing the adverse effect resulting from side erase.

Abstract: A perpendicular magnetic recording apparatus includes a magnetic disk having a perpendicular double-layer film and a perpendicular magnetic recording head having a leading pole positioned forward along the head traveling direction, a trailing pole positioned backward along the head traveling direction at a gap length from the leading pole and having, in an air-bearing surface, a forward pole and a rearward pole of which saturation magnetic flux density is higher than that of the forward pole, and an exciting coil. A length p of the trailing pole along the head traveling direction is longer than a length T of the trailing pole in a track width direction, the length p is longer than the gap length g1, and a length p1 of the rearward pole is shorter than a length p2 of the forward pole along the head traveling direction.

Abstract: A thin-film magnetic head comprises first and second magnetic layers; a gap layer provided between the first and second magnetic layers; a coupling portion for magnetically coupling the first magnetic layer and the second magnetic layer to each other at a distance from the medium facing surface ABS; and a thin-film coil at least part of which is disposed between the first and second magnetic layers. The second magnetic layer has a pole portion layer and a yoke portion layer. The pole portion layer has a saturated magnetic flux density equal to or greater than that of the yoke portion layer. The yoke portion layer magnetically connects the upper end of the coupling portion and the rear end surface of the pole portion layer to each other.

Abstract: Provided is a thin film magnetic head capable of ensuring the strength of a perpendicular magnetic field and improving recording performance. A bottom pole portion layer and a top pole portion layer constituting a part of a main magnetic pole are formed so that a cross sectional area of a complex including front end portions of the bottom pole portion layer and the top pole portion layer is smaller than a cross sectional area of a complex including rear end portions thereof, and a width of a top edge in an exposed surface is larger than a width of a bottom edge, and is equal to or larger than a width of the exposed surface in a middle position between the top edge and the bottom edge. In recording, magnetic fluxes flowing in a main magnetic pole are focused toward an air bearing surface, and are concentrated on the front end portion of the top pole portion layer which is a main emitting portion of the magnetic fluxes, so sufficient magnetic fluxes can be supplied to the air bearing surface.