JP2007087540A - Magnetic head for perpendicular magnetic recording, head gimbal assembly, head arm assembly, and magnetic disk drive - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce an effective track width and to suppress the occurrence of pole erasure. <P>SOLUTION: The magnetic head for a perpendicular magnetic recording includes a surface opposite to medium, a coil and a magnetic pole layer 15. The magnetic pole layer 15 includes a track width regulating section 15A, one end part of which is arranged on the surface opposite to the medium, and a wide width section having the width larger than that of the track width regulating section 15A while being connected to the other end part of the track width regulating section 15A. The track width regulating section 15A includes a track width regulating face A1 arranged on front side of a recording medium in the advancing direction and two side wall sections A3, A4 arranged on both sides of the recording medium in the track width direction. Further, the magnetic head for perpendicular magnetic recording is furnished with antiferromagnetic films 32 which are arranged so as to confront with the side wall sections A3, A4 for generating an exchange coupling magnetic field at a part of the track width regulating section 15A adjacent to the side wall sections A3, A4 to face a magnetization in this part toward the direction parallel to the surface opposite to medium. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a magnetic head for perpendicular magnetic recording used for recording information on a recording medium by a perpendicular magnetic recording system, a head gimbal assembly including a magnetic head for perpendicular magnetic recording, a head arm assembly, and a magnetic disk device.

  The recording method in the magnetic recording / reproducing apparatus includes a longitudinal magnetic recording method in which the direction of signal magnetization is the in-plane direction (longitudinal direction) of the recording medium, and a direction of signal magnetization in a direction perpendicular to the surface of the recording medium. There is a perpendicular magnetic recording system. It is said that the perpendicular magnetic recording system is less susceptible to thermal fluctuations of the recording medium than the longitudinal magnetic recording system and can achieve a high linear recording density.

  As magnetic heads for perpendicular magnetic recording, single-pole heads and shield-type heads are known. The single pole head has a medium facing surface that faces the recording medium, a coil that generates a magnetic field according to information recorded on the recording medium, and an end face that is disposed on the medium facing surface. A magnetic pole layer (main magnetic pole) for passing a corresponding magnetic flux and generating a recording magnetic field for recording information on a recording medium by a perpendicular magnetic recording method, and an end face disposed on the medium facing surface, the medium facing surface An auxiliary magnetic pole connected to the magnetic pole layer at a position away from the magnetic pole layer, and a gap layer made of a nonmagnetic material and provided between the magnetic pole layer and the auxiliary magnetic pole. In the medium facing surface, the end face of the auxiliary magnetic pole is disposed behind the end face of the pole layer in the traveling direction of the recording medium.

  The shield type head has a medium facing surface that faces the recording medium, a coil that generates a magnetic field according to information recorded on the recording medium, and an end face that is disposed on the medium facing surface. A position having a magnetic pole layer for passing a corresponding magnetic flux and generating a recording magnetic field for recording information on a recording medium by a perpendicular magnetic recording method, and an end face disposed on the medium facing surface, and away from the medium facing surface And a gap layer provided between the pole layer and the shield layer, which is made of a nonmagnetic material. In the medium facing surface, the end face of the shield layer is disposed on the front side in the traveling direction of the recording medium with a predetermined small gap depending on the thickness of the gap layer with respect to the end face of the pole layer. In the shield type head, the shield layer can make the magnetic field gradient steep by sucking the magnetic flux generated from the pole layer. Therefore, according to the shield type head, the linear recording density can be further improved. The magnetic field gradient refers to the amount of change per unit length in the traveling direction of the recording medium of the component in the direction perpendicular to the surface of the recording medium in the magnetic field generated from the pole layer.

  In both the single magnetic pole head and the shield type head, the pole layer has, for example, one end portion disposed on the medium facing surface, and a track width defining portion that defines the track width and the other end portion of the track width defining portion. And a wide portion having a larger width than the track width defining portion. The track width defining portion has a substantially constant width. The width of the wide portion is, for example, equal to the width of the track width defining portion at the boundary position with the track width defining portion, and gradually increases with increasing distance from the medium facing surface and then becomes a constant size.

  What is required of a magnetic head to increase the recording density is, in particular, a reduction in track width and an improvement in writing characteristics. On the other hand, when the track width is reduced, the write characteristic, for example, the overwrite characteristic representing the overwriting performance is deteriorated. Therefore, even when the track width is reduced, it is necessary to further improve the write characteristics.

  By the way, in a magnetic head for perpendicular magnetic recording, a phenomenon in which information recorded on a recording medium is erased by a magnetic field generated by the magnetic pole layer due to the residual magnetization of the magnetic pole layer when not in a recording operation ( In the following, it has been known that there is a case where pole erasure occurs.

  As a technique for suppressing the occurrence of pole erase, for example, techniques disclosed in Patent Documents 1 to 4 are known. Patent Document 1 describes a magnetic head in which a main magnetic pole has two magnetic layers and a nonmagnetic spacer disposed therebetween, and the two magnetic layers are antiferromagnetically coupled via the nonmagnetic spacer. ing.

  Patent Document 2 includes a stacked body in which a tip portion or at least a part of a main magnetic pole includes a first ferromagnetic film, a second ferromagnetic film, and an antiparallel coupling layer disposed therebetween. A magnetic head is described which is a soft magnetic multilayer film and the antiparallel coupling layer is an antiferromagnetic interlayer coupling between a first ferromagnetic film and a second ferromagnetic film.

  Patent Document 3 describes a magnetic head whose main pole has a magnetic multilayer film of a high saturation magnetic flux density layer and a low saturation magnetic flux density layer.

  Patent Document 4 describes a magnetic head in which a recording magnetic pole film (main magnetic pole) includes a soft magnetic film and a magnetic bias film. The magnetic bias film is, for example, a hard magnetic film disposed adjacent to the upper or lower surface of the soft magnetic film, or a ferromagnetic film and an antiferromagnetic film disposed adjacent to the upper or lower surface of the soft magnetic film. It includes a laminated film with a film and a hard magnetic film disposed on both side ends of the soft magnetic film.

  Patent Document 5 describes a technique in which an antiferromagnetic film is arranged on the entire surface or the main part of the magnetic domain of the main magnetic pole in order to stabilize the magnetic domain of the main magnetic pole.

JP 2004-103204 A JP 2004-199816 A JP 2004-281023 A JP 2005-38535 A JP-A-7-14118

  Conventionally, the effective track width has been reduced by reducing the physical width of the track width defining portion, that is, the optical track width. However, reducing the physical width of the track width defining portion is difficult in the magnetic head manufacturing process and leads to a decrease in yield. Further, when the physical width of the track width defining portion is reduced, the shape magnetic anisotropy of the track width defining portion tends to increase, and as a result, there arises a problem that pole erasure is likely to occur.

  With the techniques disclosed in Patent Documents 1 to 5, it is possible to suppress the occurrence of pole erase, but it is not possible to reduce the effective track width.

  The present invention has been made in view of such problems, and a first object thereof is to provide a magnetic head for perpendicular magnetic recording that can easily reduce the effective track width, and a magnetic for this perpendicular magnetic recording. It is an object to provide a head gimbal assembly having a head, a head arm assembly, and a magnetic disk apparatus.

  In addition to the first object, a second object of the present invention is a magnetic head for perpendicular magnetic recording capable of suppressing the occurrence of pole erasure, and a head gimbal assembly and head having the magnetic head for perpendicular magnetic recording. An object is to provide an arm assembly and a magnetic disk device.

The magnetic head for perpendicular magnetic recording of the present invention is
A medium facing surface facing the recording medium;
A coil that generates a magnetic field according to information to be recorded on the recording medium;
A magnetic pole layer having an end face disposed on the medium facing surface and passing a magnetic flux corresponding to the magnetic field generated by the coil and generating a recording magnetic field for recording information on the recording medium by a perpendicular magnetic recording method; I have.

  The pole layer has a track width defining portion whose one end is disposed on the medium facing surface, and a wide portion connected to the other end of the track width defining portion and having a width larger than the track width defining portion. Yes. The track width defining portion has a track width defining surface disposed on the front side in the traveling direction of the recording medium and two side wall portions disposed on both sides in the track width direction. The width of the track width defining surface on the medium facing surface defines the optical track width. The magnetic head for perpendicular magnetic recording according to the present invention is further arranged so as to face the side wall, and in a part of the track width defining portion adjacent to the side wall, the magnetization in the part is parallel to the medium facing surface. An antiferromagnetic film that generates an exchange coupling magnetic field directed toward the surface.

  In the magnetic head for perpendicular magnetic recording according to the present invention, the antiferromagnetic film disposed so as to face the side wall portion of the track width defining portion causes a portion of the track width defining portion adjacent to the side wall portion to partially An exchange coupling magnetic field is generated that directs the magnetization in the portion in a direction parallel to the medium facing surface. Thereby, the magnetization direction of a part of the track width defining portion adjacent to the side wall portion is fixed in a direction parallel to the recording medium, and as a result, the effective track width is reduced.

  In the magnetic head for perpendicular magnetic recording of the present invention, the antiferromagnetic film may be disposed so as to face the track width defining surface.

  In the magnetic head for perpendicular magnetic recording of the present invention, the track width defining portion further has an opposite surface disposed on the side opposite to the track width defining surface, and the antiferromagnetic film also faces the opposite surface. It may be arranged as follows.

  In the magnetic head for perpendicular magnetic recording of the present invention, the antiferromagnetic film may be disposed so as to face the track width defining surface and the opposite surface.

  In the magnetic head for perpendicular magnetic recording of the present invention, the antiferromagnetic film may be in contact with the track width defining portion.

  The magnetic head for perpendicular magnetic recording according to the present invention further includes a nonmagnetic metal film having one surface in contact with the track width defining portion and a soft magnetic film having one surface in contact with the other surface of the nonmagnetic metal film. The antiferromagnetic film may be in contact with the other surface of the soft magnetic film.

  The head gimbal assembly of the present invention includes the magnetic head for perpendicular magnetic recording of the present invention, and includes a slider disposed so as to face the recording medium and a suspension that elastically supports the slider.

  The head arm assembly of the present invention includes the magnetic head for perpendicular magnetic recording of the present invention, a slider arranged to face the recording medium, a suspension that elastically supports the slider, and the slider across the track of the recording medium. And an arm for moving in the direction, and the suspension is attached to the arm.

  A magnetic disk device of the present invention includes a magnetic head for perpendicular magnetic recording of the present invention, a slider disposed so as to face a disk-shaped recording medium that is rotationally driven, a slider that supports the slider, and that is against the recording medium And a positioning device for positioning.

  In the present invention, due to the action of the antiferromagnetic film disposed so as to face the side wall portion of the track width defining portion, the magnetization of a part of the track width defining portion adjacent to the side wall portion is changed to the medium facing surface. An exchange coupling magnetic field is generated in a direction parallel to. Thereby, the magnetization direction of a part of the track width defining portion adjacent to the side wall portion is fixed in a direction parallel to the recording medium, and as a result, the effective track width is reduced. Therefore, according to the present invention, there is an effect that the effective track width can be easily reduced. Further, according to the present invention, the action of the antiferromagnetic film generates an exchange coupling magnetic field in a part of the track width defining part adjacent to the side wall part so that the magnetization in the part is directed in a direction parallel to the medium facing surface. As a result, it is possible to suppress the occurrence of pole erasure due to the residual magnetization of the pole layer.

  Further, in the present invention, when the antiferromagnetic film faces the track width defining surface or when the antiferromagnetic film faces the opposite surface, the occurrence of pole erase can be further suppressed. There is an effect.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
[First Embodiment]
First, the configuration of the magnetic head for perpendicular magnetic recording according to the first embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a front view showing the medium facing surface of the magnetic head for perpendicular magnetic recording according to the present embodiment. FIG. 2 is a cross-sectional view showing the configuration of the magnetic head for perpendicular magnetic recording according to the present embodiment. FIG. 2 shows a cross section perpendicular to the medium facing surface and the surface of the substrate. Further, the arrow indicated by the symbol T in FIG. 2 represents the traveling direction of the recording medium.

As shown in FIGS. 1 and 2, the magnetic head for perpendicular magnetic recording according to the present embodiment (hereinafter simply referred to as a magnetic head) is made of a ceramic material such as AlTiC (Al ₂ O ₃ .TiC). A substrate 1, an insulating layer 2 made of an insulating material such as alumina (Al ₂ O ₃ ) formed on the substrate 1, and a lower shield layer 3 made of a magnetic material formed on the insulating layer 2. An MR (magnetoresistive effect) element 5 as a reproducing element formed on the lower shield layer 3 via the insulating layer 4 and an insulating layer 4 formed on the MR element 5 And a first upper shield layer 6 made of a magnetic material. For example, NiFe is used as the magnetic material constituting the lower shield layer 3 and the first upper shield layer 6. The thickness of the lower shield layer 3 is, for example, 1 to 2 μm. The thickness of the first upper shield layer 6 is, for example, 1.5 μm.

  One end of the MR element 5 is disposed on a medium facing surface (air bearing surface) ABS facing the recording medium. As the MR element 5, an element using a magnetosensitive film exhibiting a magnetoresistance effect such as an AMR (anisotropic magnetoresistance effect) element, a GMR (giant magnetoresistance effect) element, or a TMR (tunnel magnetoresistance effect) element is used. be able to. The GMR element may be a CIP (Current In Plane) type in which a current for detecting a magnetic signal flows in a direction substantially parallel to the surface of each layer constituting the GMR element, or a current for detecting a magnetic signal may be used. A CPP (Current Perpendicular to Plane) type that flows in a direction substantially perpendicular to the surface of each layer constituting the GMR element may be used.

  The magnetic head further includes a nonmagnetic layer 7 made of a nonmagnetic material such as alumina formed on the first upper shield layer 6 and a second magnetic material formed on the nonmagnetic layer 7. The upper shield layer 8 is provided. The thickness of the nonmagnetic layer 7 is, for example, 0.2 μm. For example, NiFe is used as the magnetic material constituting the second upper shield layer 8. The thickness of the second upper shield layer 8 is, for example, 1.1 μm. A portion from the lower shield layer 3 to the second upper shield layer 8 constitutes a reproducing head.

  The magnetic head further includes an insulating layer 9 made of an insulating material such as alumina disposed on the second upper shield layer 8, a coil 10 disposed on the insulating layer 9, and between the windings of the coil 10. And an insulating layer 11 disposed around the insulating layer 11 and an insulating layer 12 disposed around the insulating layer 11. The insulating layers 9 and 12 are made of an insulating material such as alumina. The coil 10 has a planar spiral shape. The coil 10 is formed of a conductive material such as copper. The insulating layer 11 is made of an insulating material such as a photoresist. The upper surfaces of the coil 10 and the insulating layers 11 and 12 are flattened.

  The magnetic head further includes an insulating layer 13 made of an insulating material such as alumina disposed on the upper surfaces of the coil 10 and the insulating layers 11 and 12, and a nonmagnetic material such as alumina disposed on the insulating layer 13. A nonmagnetic layer 14, an antiferromagnetic film 31 made of an antiferromagnetic material disposed on the nonmagnetic layer 14, and a pole layer 15 made of a magnetic material disposed on the antiferromagnetic film 31. I have.

  The magnetic head is further made of an insulating material such as alumina, and is formed of an insulating layer 16 disposed around the pole layer 15 and an antiferromagnetic material disposed between a part of the pole layer 15 and the insulating layer 16. And an antiferromagnetic film 33 made of an antiferromagnetic material and disposed on a part of the pole layer 15. The top surfaces of the pole layer 15, the insulating layer 16, and the antiferromagnetic film 32 are planarized. For example, NiFe, FeCoNi, or FeCo is used as the magnetic material constituting the pole layer 15. The shape of the pole layer 15 and the positional relationship between the antiferromagnetic films 31, 32, 33 and the pole layer 15 will be described in detail later.

  The magnetic head further includes a gap layer 17 made of a nonmagnetic material such as alumina disposed on the pole layer 15 and the antiferromagnetic film 33, and a magnetic material disposed on the pole layer 15 and the insulating layer 16. A yoke layer 18 is provided. One end of the gap layer 17 is disposed on the medium facing surface ABS. The end of the yoke layer 18 on the medium facing surface ABS side is disposed at a position away from the medium facing surface ABS. For example, NiFe, FeCoNi, or FeCo is used as the magnetic material constituting the yoke layer 18.

  The magnetic head further includes a recording shield layer 20 made of a magnetic material. The write shield layer 20 has a first layer 20A disposed on the gap layer 17 and a second layer 20B disposed on the first layer 20A. For example, NiFe, FeCoNi, or FeCo is used as the magnetic material constituting the first layer 20A and the second layer 20B.

  The magnetic head further includes an insulating layer 21 made of an insulating material such as alumina and disposed around the yoke layer 18 and the first layer 20A. The upper surfaces of the yoke layer 18, the first layer 20A, and the insulating layer 21 are flattened.

  The magnetic head further includes an insulating layer 22 formed on the yoke layer 18 and the insulating layer 21 at a position where a coil 23 described later is to be disposed, a coil 23 disposed on the insulating layer 22, and a coil. And an insulating layer 24 covering 23. The insulating layer 22 is made of an insulating material such as alumina. The coil 23 has a planar spiral shape. The coil 23 is formed of a conductive material such as copper. The insulating layer 24 is made of an insulating material such as a photoresist. The second layer 20 </ b> B is disposed so as to pass over a part of the coil 23 covered with the insulating layer 24 and connect the first layer 20 </ b> A and the yoke layer 18. A portion from the insulating layer 9 to the second layer 20B of the recording shield layer 20 constitutes a recording head.

  The magnetic head further includes a protective layer 25 made of an insulating material such as alumina formed so as to cover the recording shield layer 20.

  As described above, the magnetic head according to the present embodiment includes the medium facing surface ABS facing the recording medium, the reproducing head, and the recording head. The reproducing head is disposed on the rear side (the air inflow end side of the slider) of the recording medium in the traveling direction T, and the recording head is disposed on the front side (the air outflow end side of the slider) of the recording medium in the traveling direction T. In this magnetic head, information is recorded on a recording medium by the recording head, and information recorded on the recording medium is reproduced by the reproducing head.

  The reproducing head is arranged such that the MR element 5 serving as a reproducing element and a part on the medium facing surface ABS side face each other with the MR element 5 interposed therebetween, and the lower shield layer 3 for shielding the MR element 5 and the first shield layer. A first upper shield layer 6, an insulating layer 4 provided between the MR element 5 and the lower shield layer 3 and between the MR element 5 and the first upper shield layer 6, a reproducing head and a recording head. A second upper shield layer 8 for shielding each other, and a nonmagnetic layer 7 disposed between the first upper shield layer 6 and the second upper shield layer 8 are provided. Instead of the first upper shield layer 6, the nonmagnetic layer 7, and the second upper shield layer 8, a single upper shield layer may be provided. Note that the second upper shield layer 8 also has a function as an auxiliary magnetic pole in the recording head.

  The recording head includes a coil 10, insulating layers 11 to 13, a nonmagnetic layer 14, a pole layer 15, an insulating layer 16, a gap layer 17, a yoke layer 18, a recording shield layer 20, an insulating layer 21, a coil 23, an insulating layer 22, 24 and antiferromagnetic films 31-33. The coils 10 and 23 generate a magnetic field corresponding to information recorded on the recording medium. Note that the coil 10 is not an essential component of the recording head and may not be provided.

  The pole layer 15 has an end face disposed on the medium facing surface ABS, passes a magnetic flux corresponding to the magnetic field generated by the coil 23, and records information on the recording medium by the perpendicular magnetic recording method. Is generated. The recording shield layer 20 has an end face disposed on the medium facing surface ABS, and is connected to the pole layer 15 via the yoke layer 18 at a position away from the medium facing surface ABS. The gap layer 17 is made of a nonmagnetic material, has an end surface disposed on the medium facing surface ABS, and is provided between the pole layer 15 and the write shield layer 20.

  In the medium facing surface ABS, the end surface of the recording shield layer 20 is spaced from the end surface of the pole layer 15 by a predetermined distance depending on the thickness of the antiferromagnetic film 33 and the gap layer 17 in the front side of the recording medium traveling direction T ( It is arranged on the air outflow end side of the slider). The width of the end face of the write shield layer 20 is larger than the width of the end face of the pole layer 15. Further, the area of the end face of the write shield layer 20 is larger than the area of the end face of the pole layer 15. The recording shield layer 20 can make the magnetic field gradient steep by sucking the magnetic flux generated from the pole layer 15. The width of the end face of the pole layer 15 and the width of the end face of the write shield layer 20 refer to the length in the track width direction of the end face of the pole layer 15 and the end face of the write shield layer 20, respectively.

  The recording shield layer 20 also has a function of returning a magnetic flux generated from the end face of the pole layer 15 and magnetizing the recording medium. Further, the second layer 20B of the recording shield layer 20 mainly magnetically shields unnecessary spreading components of the return magnetic flux generated from the end face of the pole layer 15 before reaching the recording medium. Function as.

  At least a part of the coil 23 is disposed between the pole layer 15 and the write shield layer 20 in a state of being insulated from the pole layer 15 and the write shield layer 20. The pole layer 15, the yoke layer 18, and the recording shield layer 20 constitute a magnetic path that allows a magnetic flux corresponding to the magnetic field generated by the coil 23 to pass therethrough.

  Next, the shape of the pole layer 15 and the positional relationship between the antiferromagnetic films 31, 32, 33 and the pole layer 15 will be described in detail with reference to FIGS. FIG. 3 is a plan view showing the pole layer 15 and the antiferromagnetic film 33. FIG. 4 is a front view showing the end face of the pole layer 15 disposed on the medium facing surface ABS and the vicinity thereof.

  As shown in FIG. 3, the pole layer 15 is connected to a track width defining portion 15A having one end disposed on the medium facing surface ABS and the other end of the track width defining portion 15A. And a wide portion 15B having a larger width. The width of the upper surface of the track width defining portion 15A is substantially constant. The width of the upper surface of the track width defining portion 15A in the medium facing surface ABS defines the track width. The width of the wide portion 15B is, for example, equal to the width of the track width defining portion 15A at the boundary with the track width defining portion 15A, and gradually increases with increasing distance from the medium facing surface ABS, and then becomes a constant size. It has become. The width of the write shield layer 20 is larger than the width of the wide portion 15B.

  As shown in FIG. 4, the track width defining portion 15A includes a track width defining surface A1 disposed on the front side in the traveling direction of the recording medium, and an opposite surface A2 disposed on the opposite side of the track width defining surface A1. And two side wall portions A3 and A4 arranged on both sides in the track width direction. The width of the track width defining surface A1 in the medium facing surface ABS defines the optical track width.

  The end surface of the pole layer 15 (track width defining portion 15A) disposed on the medium facing surface ABS has four sides formed by the opposite surfaces A2 of the track width defining surface A1 and the end portions of the two side wall portions A3 and A4. Has a trapezoidal shape. The width of the end face of the pole layer 15 is reduced as it approaches the side formed by the end of the opposite surface A2, that is, as it approaches the substrate 1. As a result, it is possible to suppress a phenomenon in which information on an adjacent track is erased when writing information on a certain track due to skew. Note that the skew is the inclination of the magnetic head with respect to the tangent of the circular track in the disk-shaped recording medium. Note that the shape of the end face of the pole layer 15 may be a rectangle or a square. The pole layer 15 may have a triangular prism shape without the opposite surface A2. In this case, the shape of the end face of the pole layer 15 is a triangle.

  The width of the track width defining surface A1 in the medium facing surface ABS, that is, the optical track width is, for example, 0.08 μm or more and 0.25 μm or less. The thickness of the pole layer 15 in the medium facing surface ABS is preferably 0.1 μm or more and 0.4 μm or less. If the thickness of the pole layer 15 is less than 0.1 μm, it becomes difficult to generate a sufficient recording magnetic field from the end face of the pole layer 15. On the other hand, if the thickness of the pole layer 15 exceeds 0.4 μm, the width of the region where information is erased due to skew increases on both sides of the track to be recorded or reproduced, and the track density is increased. It becomes difficult to do.

  As shown in FIG. 4, the antiferromagnetic film 31 is disposed so as to face the opposite surface A2. The antiferromagnetic film 32 is disposed so as to face the two side wall portions A3 and A4. The antiferromagnetic film 33 is disposed so as to face the track width defining surface A1. In the present embodiment, in particular, all of the antiferromagnetic films 31 to 33 are in contact with the track width defining portion 15A.

  In the example shown in FIGS. 1 to 4, the width of the antiferromagnetic film 31 is larger than the width of the write shield layer 20. In this example, the width of the antiferromagnetic film 33 is larger than the width of the track width defining surface A1 and smaller than the maximum width of the wide portion 15B. The width of the antiferromagnetic film 31 may be equal to or greater than the width of the opposite surface A2, and the width of the antiferromagnetic film 33 may be equal to or greater than the width of the track width defining surface A1.

  In the example shown in FIGS. 1 to 4, the antiferromagnetic film 31 faces (contacts) not only the opposite surface A2 but also the entire lower surface of the wide portion 15B. In this example, the antiferromagnetic film 32 does not face (contact) the side surface of the wide portion 15B, and the antiferromagnetic film 33 does not face (contact) the upper surface of the wide portion 15B. The antiferromagnetic film 31 only has to face (contact) at least the opposite surface A2 that is the lower surface of the track width defining portion 15A among the lower surfaces of the pole layer 15. The antiferromagnetic film 32 only needs to face (contact) the side wall portions A3 and A4 which are at least the side surfaces of the track width defining portion 15A among the side surfaces of the pole layer 15. Further, the antiferromagnetic film 33 only needs to face (contact) the medium facing surface A <b> 1 that is at least the top surface of the track width defining portion 15 </ b> A among the top surfaces of the pole layer 15.

  The antiferromagnetic film 31 generates an exchange coupling magnetic field in a part of the track width defining portion 15A adjacent to the opposite surface A2 so that the magnetization in the part is directed in a direction parallel to the medium facing surface ABS. The antiferromagnetic film 32 generates an exchange coupling magnetic field in a part of the track width defining part 15A adjacent to the side wall parts A3 and A4 so that the magnetization in the part is directed in a direction parallel to the medium facing surface ABS. The antiferromagnetic film 33 generates an exchange coupling magnetic field in a part of the track width defining portion 15A adjacent to the track width defining surface A1 so that the magnetization in the part is directed in a direction parallel to the medium facing surface ABS. That is, between the antiferromagnetic film 31 and a portion of the track width defining portion 15A adjacent to the opposite surface A2, and between the antiferromagnetic film 32 and a portion of the track width defining portion 15A adjacent to the side wall portions A3 and A4. In the meantime, exchange coupling occurs between the antiferromagnetic film 33 and a part of the track width defining portion 15A adjacent to the track width defining surface A1, and as a result, the track width defining surface A1, the opposite surface A2, and the side wall portion. The direction of magnetization of a part of the track width defining portion 15A adjacent to A3 and A4, that is, an annular portion between the broken line in FIG. 4 and the outer periphery of the track width defining portion 15A is fixed in a direction parallel to the recording medium. Is done. Inside the track width defining portion 15A, the width of the annular portion where the magnetization direction is fixed by the antiferromagnetic films 31 to 33 is about 10 nm. In FIG. 4, the arrow in the track width defining portion 15A represents the direction of magnetization.

  The antiferromagnetic material constituting the antiferromagnetic films 31 to 33 may be an alloy containing manganese (Mn) such as IrMn, PtMn, NiMn, FeMn, OsMn, RuMn, RhMn, or an oxidation of NiO, FeO, MnO, or the like. It can be a thing. The thickness of the antiferromagnetic films 31 to 33 is preferably 5 nm or more and 100 nm or less. Basically, the antiferromagnetic films 31 to 33 may be thick. However, if the antiferromagnetic film 31 is too thick, the distance between the reproducing head and the recording head becomes too large. On the other hand, if the antiferromagnetic film 33 is too thick, the distance between the end face of the pole layer 15 and the end face of the recording shield layer 20 in the medium facing surface ABS becomes too large, and the function of the recording shield layer 20 is impaired. The distance between the end face of the pole layer 15 and the end face of the write shield layer 20 in the medium facing surface ABS is preferably 0.2 μm or less.

  In the present embodiment, due to the action of the antiferromagnetic film 32 disposed so as to face the side wall portions A3 and A4, a part of the track width defining portion 15A adjacent to the side wall portions A3 and A4 is partially An exchange coupling magnetic field is generated that directs the magnetization in a direction parallel to the medium facing surface ABS. Thereby, the magnetization direction of a part of the track width defining portion 15A adjacent to the side wall portions A3 and A4 is fixed in a direction parallel to the recording medium. As a result, in the present embodiment, the effective track width is reduced as compared with the case where the antiferromagnetic film 32 is not provided. Thus, according to the present embodiment, the effective track width can be easily reduced.

  Further, according to the present embodiment, due to the action of the antiferromagnetic film 32, the magnetization in a part of the track width defining part 15A adjacent to the side wall parts A3 and A4 is parallel to the medium facing surface ABS. Since the exchange coupling magnetic field directed in the direction is generated, it is possible to suppress the occurrence of pole erase due to the residual magnetization of the pole layer 15.

  In the present embodiment, in addition to the antiferromagnetic film 32 arranged to face the side wall portions A3 and A4, the antiferromagnetic film 33 arranged to face the track width defining surface A1, And an antiferromagnetic film 31 disposed so as to face the opposite surface A2. By the action of the antiferromagnetic film 33, an exchange coupling magnetic field is generated in a part of the track width defining portion 15A adjacent to the track width defining surface A1 so that the magnetization in the part is directed in a direction parallel to the medium facing surface ABS. . Further, the action of the antiferromagnetic film 31 generates an exchange coupling magnetic field in a part of the track width defining portion 15A adjacent to the opposite surface A2 so that the magnetization in the part is directed in a direction parallel to the medium facing surface ABS. Thereby, according to the present embodiment, it is possible to further suppress the occurrence of pole erasure.

  In the present embodiment, as described above, the direction of magnetization of a part of the track width defining portion 15A adjacent to the track width defining surface A1, the opposite surface A2, and the side wall portions A3 and A4 is parallel to the recording medium. Fixed to. As a result, according to the present embodiment, it is possible to suppress the leakage of excess magnetic flux from the pole layer 15 in the vicinity of the medium facing surface ABS.

  Hereinafter, first to fifth modifications of the present embodiment will be described with reference to FIGS. FIG. 5 is a plan view showing the pole layer 15 and the antiferromagnetic film 33 in the first modification. In the first modification, the width of the antiferromagnetic film 33 is equal to the maximum width of the wide portion 15B. Note that the planar shape of the antiferromagnetic film 31 may be the same as or different from the planar shape of the antiferromagnetic film 33.

  FIG. 6 is a plan view showing the pole layer 15 and the antiferromagnetic film 33 in the second modification. In the second modification, the antiferromagnetic film 33 faces (contacts) not only the track width defining surface A1 but also a part of the upper surface of the wide portion 15B. The width of the antiferromagnetic film 33 is larger than the maximum width of the wide portion 15B. Although not shown, in the second modification, the antiferromagnetic film 32 faces (contacts) not only the side wall portions A3 and A4 but also a part of the side surface of the wide portion 15B. The distances from the medium facing surface ABS to the ends of the antiferromagnetic films 31 and 32 opposite to the medium facing surface ABS may be equal or different. Note that the planar shape of the antiferromagnetic film 31 may be the same as or different from the planar shape of the antiferromagnetic film 33.

  FIG. 7 is a plan view showing the pole layer 15 and the antiferromagnetic film 33 in the third modification. In the third modification, the antiferromagnetic film 33 faces (contacts) not only the track width defining surface A1 but also almost the entire upper surface of the wide portion 15B. In the third modification, the yoke layer 18 in FIG. 2 is not provided, and the second layer 20B of the recording shield layer 20 is connected to the upper surface of the wide portion 15B. Therefore, a contact hole 33A for connecting the second layer 20B and the upper surface of the wide portion 15B is formed in the antiferromagnetic film 33. The width of the antiferromagnetic film 33 is larger than the maximum width of the wide portion 15B. Although not shown, in the third modification, the antiferromagnetic film 32 faces (contacts) not only the side wall portions A3 and A4 but also the side surface of the wide portion 15B. Note that the planar shape of the antiferromagnetic film 31 may be the same as or different from the planar shape of the antiferromagnetic film 33.

  FIG. 8 is a front view showing the end face of the pole layer 15 disposed on the medium facing surface ABS and the vicinity thereof in the fourth modified example. In the fourth modification, the antiferromagnetic film 33 is not provided, and instead, the antiferromagnetic film 32 is disposed so as to face (contact) the track width defining surface A1. The antiferromagnetic film 32 faces (contacts) not only the track width defining surface A1 and the side wall portions A3 and A4 but also at least part of the upper surface of the wide portion 15B and at least part of the side surface of the wide portion 15B. It may be.

  FIG. 9 is a front view showing the end face of the pole layer 15 disposed on the medium facing surface ABS in the fifth modification and the vicinity thereof. The magnetic head of the fifth modification includes a nonmagnetic metal film 313 whose one surface is in contact with the opposite surface A2, and a soft magnetic film 312 whose one surface is in contact with the other surface of the nonmagnetic metal film 313. . The antiferromagnetic film 31 is in contact with the other surface of the soft magnetic film 312. The magnetic head of the fifth modification has a nonmagnetic metal film 323 whose one surface is in contact with the side wall portions A3 and A4, and a soft magnetic film 322 whose one surface is in contact with the other surface of the nonmagnetic metal film 323. It has. The antiferromagnetic film 32 is in contact with the other surface of the soft magnetic film 322. Also. The magnetic head of the fifth modification includes a nonmagnetic metal film 333 whose one surface is in contact with the track width defining surface A1, and a soft magnetic film 332 whose one surface is in contact with the other surface of the nonmagnetic metal film 333. ing. The antiferromagnetic film 33 is in contact with the other surface of the soft magnetic film 332.

  As a material constituting the nonmagnetic metal films 313, 323, 333, for example, any of Ru, Rh, Ir, Re, Cr, Zr, and Cu can be used. The soft magnetic films 312, 322, and 332 are made of, for example, CoFe. The thickness of the nonmagnetic metal films 313, 323, and 333 is set to a thickness that causes RKKY exchange interaction between the soft magnetic films 312, 322, and 332 and the pole layer 15.

  In the fifth modification, exchange is performed between the antiferromagnetic film 31 and the soft magnetic film 312, between the antiferromagnetic film 32 and the soft magnetic film 322, and between the antiferromagnetic film 33 and the soft magnetic film 332, respectively. Coupling occurs, and the magnetization directions of the soft magnetic films 312, 322, and 332 are fixed in a direction parallel to the medium facing surface ABS. In the fifth modification, an RKKY exchange interaction occurs between the soft magnetic films 312, 322, 332 and the pole layer 15. Thereby, the magnetization directions of the respective portions of the track width defining portion 15A adjacent to the opposite surface A2, the side wall portions A3, A4, and the track width defining surface A1 are the magnetization directions of the soft magnetic films 312, 322, and 332, respectively. Is fixed in an antiparallel direction. In the fifth modification example, as described above, the antiferromagnetic films 31 to 33 cause the magnetization of each part of the track width defining portion 15A to be parallel to the medium facing surface ABS due to the action of the antiferromagnetic films 31 to 33. An exchange coupling magnetic field directed in the direction is generated. The shapes of the antiferromagnetic films 31 to 33 in the fifth modification may be the same as those in the first to fourth modifications.

  The magnetic head according to the present embodiment can be further modified in various ways as described below. First, the yoke layer 18 may not be provided, may be provided below the pole layer 15, or may be provided above and below the pole layer 15. Further, instead of the coils 10 and 23, a coil arranged in a spiral shape with the pole layer 15 as the center may be provided. Further, the recording shield layer 20 may be formed of one layer or may be formed of three or more layers. The antiferromagnetic film 33 may also serve as a gap layer.

  Next, an example of a method for forming the pole layer 15 and the antiferromagnetic films 31 to 33 in the present embodiment will be described with reference to FIGS. FIG. 10 is a cross-sectional view showing one step in the method of forming the pole layer 15 and the antiferromagnetic films 31 to 33. In this step, first, the antiferromagnetic film 31 is formed on the nonmagnetic layer 14 by, for example, sputtering. Next, an electrode film 15E for plating made of a magnetic material is formed on the antiferromagnetic film 31 by, for example, sputtering. For example, NiFe is used as the magnetic material constituting the electrode film 15E. Next, a photoresist layer is formed on the electrode film 15E. Next, this photoresist layer is patterned to form a frame 41 for forming a plating film constituting the pole layer 15. The frame 41 has a groove 41 a having a shape corresponding to the shape of the pole layer 15.

  FIG. 11 shows the next step. In this step, first, a plating film 15P made of a magnetic material is formed in the groove 41a of the frame 41 by electrolytic plating. For example, FeCoNi (Fe: 65 wt%, Co: 30 wt%, Ni: 5 wt%) is used as the magnetic material constituting the plating film 15P. Next, the frame 41 is removed.

  FIG. 12 shows the next step. In this step, first, using the plating film 15P as a mask, portions other than the portion existing below the plating film 15P in the electrode film 15E are etched and removed by, for example, ion milling. At the same time, the side wall portion of the plating film 15P may be etched to change the shape of the plating film 15P to a desired shape. Next, although not shown, the plating film 15P is covered with a patterned photoresist layer, and then the excess plating film other than the plating film 15P is removed by etching. The remaining electrode film 15E and plating film 15P constitute the pole layer 15. Next, a photoresist layer 42 is formed over the entire top surface of the stack obtained through the steps so far. Next, the photoresist layer 42 is patterned to form openings 42 a in the photoresist layer 42. The opening 42a is disposed in a region including the track width defining portion 15A of the pole layer 15 and its periphery.

  FIG. 13 shows the next step. In this step, first, the antiferromagnetic film 32 is formed on the upper surface of the stacked body exposed from the opening 42a, for example, by ion beam sputtering. The antiferromagnetic film 32 is formed so as to cover the upper surface and the side wall portion of the track width defining portion 15A. In order to form the antiferromagnetic film 32 having a sufficient thickness also on the side wall portion, when the antiferromagnetic film 32 is formed, the angle formed by the traveling direction of the ion beam with respect to the upper surface of the nonmagnetic layer 14 is small. For example, it is set to 20 °. Next, the photoresist layer 42 is removed. Next, the insulating layer 16 is formed over the entire top surface of the stack by, for example, sputtering.

  FIG. 14 shows the next step. In this step, the insulating layer 16, the antiferromagnetic film 32, and the pole layer are exposed until the pole layer 15 is exposed and the pole layer 15 has a desired thickness, for example, by chemical mechanical polishing (hereinafter referred to as CMP). 15 is polished. As a result, the top surfaces of the pole layer 15, the insulating layer 16, and the antiferromagnetic film 32 are planarized. The upper surface of the track width defining portion 15A is a track width defining surface A1.

  FIG. 15 shows the next step. In this step, first, although not shown, a photoresist layer is formed over the entire top surface of the stack. Next, the photoresist layer is patterned to form openings in the photoresist layer. The opening is disposed in a region including the track width defining portion 15A of the pole layer 15 and its periphery. Next, an antiferromagnetic film 33 is formed on the upper surface of the stacked body exposed from the opening by, for example, ion beam sputtering. The antiferromagnetic film 33 is in contact with the track width defining plane A1.

  FIG. 16 shows the next step. In this step, first, the gap layer 17 is formed on the stacked body by, for example, sputtering. Next, the first layer 20 </ b> A of the write shield layer 20 is formed on the gap layer 17. The first layer 20A may be formed by frame plating, for example, or may be formed by patterning a film formed by plating or sputtering by etching.

  The structure of the fourth modification shown in FIG. 8 is arranged on the upper surface of the track width defining portion 15A in the antiferromagnetic film 32 after the insulating film 16 is formed as shown in FIG. This can be realized by polishing the insulating layer 16 so that the etched portion remains.

  Further, in the structure of the fifth modification shown in FIG. 9, the soft magnetic film 312 and the nonmagnetic metal film 313 are formed after the antiferromagnetic film 31 is formed, and the nonmagnetic metal is formed before the antiferromagnetic film 32 is formed. This can be realized by forming the film 323 and the soft magnetic film 322 and forming the nonmagnetic metal film 333 and the soft magnetic film 332 before the antiferromagnetic film 33 is formed.

  Hereinafter, a head gimbal assembly, a head arm assembly, and a magnetic disk device according to the present embodiment will be described. First, the slider 210 included in the head gimbal assembly will be described with reference to FIG. In the magnetic disk device, the slider 210 is disposed so as to face a magnetic disk that is a disk-shaped recording medium that is rotationally driven. The slider 210 includes a base body 211 mainly composed of the substrate 1 and the protective layer 25 in FIG. The base body 211 has a substantially hexahedral shape. One of the six surfaces of the substrate 211 faces the magnetic disk. On this one surface, a medium facing surface (air bearing surface) ABS is formed. When the magnetic disk rotates in the Z direction in FIG. 17, an air flow passing between the magnetic disk and the slider 210 causes a lift in the slider 210 in the lower direction in the Y direction in FIG. The slider 210 floats from the surface of the magnetic disk by this lifting force. Note that the X direction in FIG. 17 is the track crossing direction of the magnetic disk. Near the end of the slider 210 on the air outflow side (lower left end in FIG. 17), the magnetic head 100 according to the present embodiment is formed.

  Next, the head gimbal assembly 220 according to the present embodiment will be described with reference to FIG. The head gimbal assembly 220 includes a slider 210 and a suspension 221 that elastically supports the slider 210. The suspension 221 is, for example, a leaf spring-shaped load beam 222 formed of stainless steel, a flexure 223 that is provided at one end of the load beam 222 and is joined to the slider 210 to give the slider 210 an appropriate degree of freedom. And a base plate 224 provided at the other end of the beam 222. The base plate 224 is attached to an arm 230 of an actuator for moving the slider 210 in the track crossing direction X of the magnetic disk 262. The actuator has an arm 230 and a voice coil motor that drives the arm 230. In the flexure 223, a part to which the slider 210 is attached is provided with a gimbal part for keeping the posture of the slider 210 constant.

  The head gimbal assembly 220 is attached to the arm 230 of the actuator. A structure in which the head gimbal assembly 220 is attached to one arm 230 is called a head arm assembly. Further, a head gimbal assembly 220 attached to each arm of a carriage having a plurality of arms is called a head stack assembly.

  FIG. 18 shows a head arm assembly according to the present embodiment. In this head arm assembly, a head gimbal assembly 220 is attached to one end of the arm 230. A coil 231 that is a part of the voice coil motor is attached to the other end of the arm 230. A bearing portion 233 attached to a shaft 234 for rotatably supporting the arm 230 is provided at an intermediate portion of the arm 230.

  Next, an example of the head stack assembly and the magnetic disk device according to the present embodiment will be described with reference to FIGS. FIG. 19 is an explanatory view showing the main part of the magnetic disk device, and FIG. 20 is a plan view of the magnetic disk device. The head stack assembly 250 has a carriage 251 having a plurality of arms 252. A plurality of head gimbal assemblies 220 are attached to the plurality of arms 252 so as to be arranged in the vertical direction at intervals. A coil 253 that is a part of the voice coil motor is attached to the carriage 251 on the side opposite to the arm 252. The head stack assembly 250 is incorporated in a magnetic disk device. The magnetic disk device has a plurality of magnetic disks 262 attached to a spindle motor 261. Two sliders 210 are arranged for each magnetic disk 262 so as to face each other with the magnetic disk 262 interposed therebetween. Further, the voice coil motor has permanent magnets 263 arranged at positions facing each other with the coil 253 of the head stack assembly 250 interposed therebetween.

  The head stack assembly 250 and the actuator excluding the slider 210 correspond to the positioning device in the present invention, and support the slider 210 and position it relative to the magnetic disk 262.

  In the magnetic disk device according to the present embodiment, the slider 210 is moved with respect to the magnetic disk 262 by the actuator so that the slider 210 is positioned with respect to the magnetic disk 262. The magnetic head included in the slider 210 records information on the magnetic disk 262 by the recording head, and reproduces information recorded on the magnetic disk 262 by the reproducing head.

  The head gimbal assembly, head arm assembly, and magnetic disk device according to the present embodiment have the same effects as the magnetic head according to the present embodiment described above.

[Second Embodiment]
Next, a second embodiment of the present invention will be described with reference to FIG. FIG. 21 is a front view showing the end face of the pole layer 15 disposed on the medium facing surface ABS and the vicinity thereof in the present embodiment. In the present embodiment, the antiferromagnetic films 31 and 33 are not provided. In the present embodiment, the pole layer 15, the antiferromagnetic film 32, and the insulating layer 16 are disposed on the nonmagnetic layer 14. In the present embodiment, the gap layer 17 is disposed so as to contact the track width defining surface A1.

  In the present embodiment, among the antiferromagnetic films 31 to 33 in the first embodiment, only the antiferromagnetic film 32 facing (contacting) the side wall portions A3 and A4 is provided. Therefore, in the present embodiment, the effect of suppressing the occurrence of pole erasure is smaller than that in the first embodiment. Nevertheless, according to the present embodiment, it is possible to suppress the occurrence of pole erase as compared with the case where the antiferromagnetic film 32 is not provided. Other configurations, operations, and effects in the present embodiment are the same as those in the first embodiment.

[Third Embodiment]
Next, a third embodiment of the present invention will be described with reference to FIG. FIG. 22 is a front view showing the end face of the pole layer 15 disposed on the medium facing surface ABS and the vicinity thereof in the present embodiment. In the present embodiment, the antiferromagnetic film 31 is not provided. In the present embodiment, the pole layer 15, the antiferromagnetic film 32, and the insulating layer 16 are disposed on the nonmagnetic layer 14.

  FIG. 23 is a front view showing the end face of the pole layer 15 disposed on the medium facing surface ABS and the vicinity thereof in a modification of the present embodiment. In this modified example, as in the fourth modified example of the first embodiment, the antiferromagnetic film 33 is not provided. Instead, the antiferromagnetic film 32 also faces the track width defining surface A1. (Contact) is arranged.

  In the present embodiment, among the antiferromagnetic films 31 to 33 in the first embodiment, the antiferromagnetic film 31 facing (contacting) the opposite surface A2 is not provided. Therefore, in the present embodiment, the effect of suppressing the occurrence of pole erasure is smaller than that in the first embodiment. Nevertheless, according to the present embodiment, it is possible to suppress the occurrence of pole erase as compared with the case where the antiferromagnetic films 32 and 33 are not provided. Other configurations, operations, and effects in the present embodiment are the same as those in the first embodiment.

[Fourth Embodiment]
Next, a fourth embodiment of the present invention will be described with reference to FIG. FIG. 24 is a front view showing the end face of the pole layer 15 disposed on the medium facing surface ABS in the present embodiment and the vicinity thereof. In the present embodiment, the antiferromagnetic film 33 is not provided. In the present embodiment, the gap layer 17 is disposed in contact with the track width defining surface A1.

  In the present embodiment, among the antiferromagnetic films 31 to 33 in the first embodiment, the antiferromagnetic film 33 facing (contacting) the track width defining surface A1 is not provided. Therefore, in the present embodiment, the effect of suppressing the occurrence of pole erasure is smaller than that in the first embodiment. Nevertheless, according to the present embodiment, it is possible to suppress the occurrence of pole erase as compared with the case where the antiferromagnetic films 31 and 32 are not provided. Other configurations, operations, and effects in the present embodiment are the same as those in the first embodiment.

[Experimental result]
Next, the results of experiments conducted to confirm the effects of the magnetic head according to the first to fourth embodiments will be described. In this experiment, the effective track width and the degree of occurrence of pole erasure were examined for the samples of the magnetic heads of Example 1, Example 2, Example 3-1, Example 3-2, Example 4 and Comparative Example. .

  Example 1 is an example of the first embodiment. The magnetic head of Example 1 includes antiferromagnetic films 31 to 33 as shown in FIG. In Example 1, the antiferromagnetic material constituting the antiferromagnetic films 31 to 33 is NiO. The thickness of the antiferromagnetic films 31 to 33 is 50 nm.

  Example 2 is an example of the second embodiment. The magnetic head of Example 2 includes an antiferromagnetic film 32 as shown in FIG. In Example 2, the antiferromagnetic material forming the antiferromagnetic film 32 is NiO. The antiferromagnetic film 32 has a thickness of 50 nm.

  Example 3-1 is an example of the third embodiment. The magnetic head of Example 3-1 includes antiferromagnetic films 32 and 33 as shown in FIG. In Example 3-1, the antiferromagnetic material constituting the antiferromagnetic films 32 and 33 is MnO. The antiferromagnetic films 32 and 33 have a thickness of 50 nm.

  Example 3-2 is also an example of the third embodiment. The magnetic head of Example 3-2 includes antiferromagnetic films 32 and 33 as shown in FIG. In Example 3-2, the antiferromagnetic material constituting the antiferromagnetic films 32 and 33 is IrMn. The antiferromagnetic films 32 and 33 have a thickness of 20 nm.

  Example 4 is an example of the fourth embodiment. The magnetic head of Example 4 includes antiferromagnetic films 31 and 32 as shown in FIG. In Example 4, the antiferromagnetic material constituting the antiferromagnetic films 31 and 32 is NiO. The antiferromagnetic films 31 and 32 have a thickness of 50 nm.

The magnetic head of the comparative example does not include any of the antiferromagnetic films 31 to 33. Pole layer 15 in the magnetic head of the comparative example, is disposed on the nonmagnetic layer 14 made of Al ₂ O _3, and is surrounded by an insulating layer 16 made of Al ₂ O _3. A gap layer 17 made of Al ₂ O ₃ is disposed on the pole layer 15 in the magnetic head of the comparative example.

  The pole layer 15 in each of the above examples and comparative examples has an electrode film 15E made of NiFe and FeCoNi formed on the electrode film 15E (Fe: 65 wt%, Co: 30 wt%, Ni: 5% by weight) of the plating film 15P. Further, the shape of the pole layer 15 in each example and comparative example is the same. The optical track width in each example and comparative example is 0.18 μm.

  Next, a method for measuring the effective track width in the experiment will be described. In the experiment, first, in the recording medium, the signal in the target track on which the signal was recorded and the signal in the region of 2 μm width on each side of the target track were erased by the AC erasing method. Next, a 26 MHz signal was recorded on the target track. Next, signals were reproduced from the target track and the regions on both sides of the target track, and a track profile representing changes in the reproduction output signal in the track width direction was created. The half width in this track profile was defined as the effective track width.

  Next, an index indicating the degree of occurrence of pole erase in the experiment will be described. In the experiment, first, one track on the recording medium was divided into 70 sectors, and high frequency (160 MHz) signals were recorded in all sectors of one track. Next, a high frequency signal was reproduced from all sectors, and an average value of the obtained reproduction output signals was obtained. This value is called initial signal output. Next, a low frequency (1 MHz) signal was overwritten at the head of each sector. Next, a high frequency signal was reproduced from a portion other than the head portion of each sector, and an average value of the obtained reproduction output signals was obtained. This value is called residual signal output. A numerical value representing the ratio of the residual signal output to the initial signal output as a percentage was defined as the residual signal intensity. This residual signal intensity is an index indicating the degree of occurrence of pole erase. In other words, it can be said that the smaller the residual signal intensity, the easier the pole erase occurs.

  The effective track width and residual signal intensity of the magnetic head samples of the examples and comparative examples are shown in the following table.

  As can be seen from the above table, the effective track width is small and the residual signal intensity is large in any of the examples compared to the comparative example. From this, it can be seen that in any of the first to fourth embodiments, the effect of reducing the effective track width and suppressing the occurrence of pole erasure is exhibited.

  Among the five embodiments, the effective track width is the smallest and the residual signal intensity is the largest in the first embodiment. From this, it can be seen that in the first embodiment, the above-described effects are most prominently exhibited. Moreover, it can be seen from the experimental results of Example 3-1 and Example 3-2 that the above-described effects are sufficiently exhibited in the third embodiment.

  In Example 2 corresponding to the second embodiment, the residual signal intensity is larger than that of the comparative example, but is smaller than that of the other examples. The reason is considered as follows. That is, in the second embodiment, the antiferromagnetic film provided around the track width defining portion 15A is only the antiferromagnetic film 32 facing (contacting) the side wall portions A3 and A4. For this reason, in the second embodiment, it is considered that the effect of fixing the magnetization direction of a part of the track width defining portion 15A in a direction parallel to the recording medium is smaller than in the other embodiments.

  In Example 4 corresponding to the fourth embodiment, the residual signal intensity is larger than that in Example 2, but compared to Examples 1, 3-1, and 3-2. It is getting smaller. The reason is considered as follows. In other words, in the fourth embodiment, in addition to the antiferromagnetic film 32, an antiferromagnetic film 31 facing (contacting) the opposite surface A2 is provided. However, the area of the opposite surface A2 is smaller than the area of the track width defining surface A1. Therefore, in the fourth embodiment, it is considered that the effect of fixing the magnetization direction of a part of the track width defining portion 15A in the direction parallel to the recording medium is smaller than that in the third embodiment.

  In addition, this invention is not limited to said each embodiment, A various change is possible. For example, the present invention can be applied not only to a shield type head but also to a single pole head.

  Further, in the embodiment, a magnetic head having a structure in which a reproducing head is formed on the substrate side and a recording head is stacked thereon has been described. However, the stacking order may be reversed.

1 is a front view showing a medium facing surface of a magnetic head for perpendicular magnetic recording according to a first embodiment of the present invention. FIG. 2 is a cross-sectional view showing the configuration of the magnetic head for perpendicular magnetic recording shown in FIG. 1. FIG. 2 is a plan view showing a pole layer and an antiferromagnetic film in the magnetic head for perpendicular magnetic recording shown in FIG. 1. FIG. 2 is a front view showing an end face of a magnetic pole layer of the magnetic head for perpendicular magnetic recording shown in FIG. 1 and its vicinity. It is a top view which shows the pole layer and antiferromagnetic film in the 1st modification of the 1st Embodiment of this invention. It is a top view which shows the pole layer and antiferromagnetic film in the 2nd modification of the 1st Embodiment of this invention. It is a top view which shows the pole layer and antiferromagnetic film in the 3rd modification of the 1st Embodiment of this invention. It is a front view which shows the end surface of the pole layer in the 4th modification of the 1st Embodiment of this invention, and its vicinity. It is a front view which shows the end surface of the pole layer in the 5th modification of the 1st Embodiment of this invention, and its vicinity. It is sectional drawing which shows 1 process in the formation method of the pole layer and antiferromagnetic film in the 1st Embodiment of this invention. FIG. 11 is a cross-sectional view showing a step that follows the step shown in FIG. 10. FIG. 12 is a cross-sectional view showing a step that follows the step shown in FIG. 11. FIG. 13 is a cross-sectional view showing a step that follows the step shown in FIG. 12. FIG. 14 is a cross-sectional view showing a step that follows the step shown in FIG. 13. FIG. 15 is a cross-sectional view showing a step that follows the step shown in FIG. 14. FIG. 16 is a cross-sectional view showing a step that follows the step shown in FIG. 15. It is a perspective view which shows the slider contained in the head gimbal assembly which concerns on the 1st Embodiment of this invention. 1 is a perspective view showing a head arm assembly according to a first embodiment of the present invention. FIG. 3 is an explanatory diagram for explaining a main part of the magnetic disk device according to the first embodiment of the invention. 1 is a plan view of a magnetic disk device according to a first embodiment of the present invention. It is a front view which shows the end surface of the magnetic pole layer of the magnetic head for perpendicular magnetic recording which concerns on the 2nd Embodiment of this invention, and its vicinity. It is a front view which shows the end surface of the pole layer of the magnetic head for perpendicular magnetic recording which concerns on the 3rd Embodiment of this invention, and its vicinity. It is a front view which shows the end surface of the pole layer in the modification of the 3rd Embodiment of this invention, and its vicinity. It is a front view which shows the end surface of the pole layer of the magnetic head for perpendicular magnetic recording which concerns on the 4th Embodiment of this invention, and its vicinity.

Explanation of symbols

3 ... lower shield layer, 4 ... insulating layer, 5 ... MR element, 6 ... first upper shield layer, 7 ... nonmagnetic layer, 8 ... second upper shield layer, 15 ... pole layer, 17 ... gap layer, 20 ... recording shield layer, 23 ... coil, 31-33 ... antiferromagnetic film.

Claims (9)

A medium facing surface facing the recording medium;
A coil that generates a magnetic field according to information to be recorded on the recording medium;
An end surface disposed on the medium facing surface, which passes a magnetic flux corresponding to the magnetic field generated by the coil, and generates a recording magnetic field for recording the information on the recording medium by a perpendicular magnetic recording method. A magnetic head for perpendicular magnetic recording comprising a pole layer,
The magnetic pole layer has a track width defining portion whose one end is disposed on the medium facing surface and a wide portion connected to the other end of the track width defining portion and having a width larger than the track width defining portion. And
The track width defining portion has a track width defining surface disposed on the front side in the traveling direction of the recording medium, and two side wall portions disposed on both sides in the track width direction,
The width of the track width defining surface at the medium facing surface defines the optical track width;
The magnetic head for perpendicular magnetic recording is further arranged so as to face the side wall portion, and a part of the track width defining portion adjacent to the side wall portion has a magnetization in a direction parallel to the medium facing surface. A magnetic head for perpendicular magnetic recording comprising an antiferromagnetic film for generating an exchange coupling magnetic field to be directed.   2. The magnetic head for perpendicular magnetic recording according to claim 1, wherein the antiferromagnetic film is disposed so as to face the track width defining surface.   The track width defining portion further has an opposite surface disposed on the opposite side of the track width defining surface, and the antiferromagnetic film is disposed so as to face the opposite surface. 2. A magnetic head for perpendicular magnetic recording according to claim 1.   The track width defining portion further has an opposite surface disposed on the opposite side of the track width defining surface, and the antiferromagnetic film is disposed so as to face the track width defining surface and the opposite surface. 2. The magnetic head for perpendicular magnetic recording according to claim 1, wherein the magnetic head is used.   5. The magnetic head for perpendicular magnetic recording according to claim 1, wherein the antiferromagnetic film is in contact with the track width defining portion.   And a nonmagnetic metal film having one surface in contact with the track width defining portion and a soft magnetic film having one surface in contact with the other surface of the nonmagnetic metal film, wherein the antiferromagnetic film includes the soft magnetic film. 5. The magnetic head for perpendicular magnetic recording according to claim 1, wherein the magnetic head is in contact with the other surface of the film. A slider including the magnetic head for perpendicular magnetic recording according to any one of claims 1 to 6 and disposed so as to face a recording medium;
A head gimbal assembly comprising a suspension for elastically supporting the slider. A slider including the magnetic head for perpendicular magnetic recording according to any one of claims 1 to 6 and disposed so as to face a recording medium;
A suspension for elastically supporting the slider;
An arm for moving the slider in a direction across the track of the recording medium, and the suspension is attached to the arm. A slider including the magnetic head for perpendicular magnetic recording according to any one of claims 1 to 6, and disposed so as to face a disk-shaped recording medium that is rotationally driven;
A magnetic disk drive comprising: a positioning device that supports the slider and positions the slider relative to the recording medium.

Images