WO2009153837A1

WO2009153837A1 - Magnetic head, manufacturing method of magnetic head, and magnetic storage device

Info

Publication number: WO2009153837A1
Application number: PCT/JP2008/001590
Authority: WO
Inventors: 今純一
Original assignee: 富士通株式会社
Priority date: 2008-06-19
Filing date: 2008-06-19
Publication date: 2009-12-23
Also published as: JPWO2009153837A1

Abstract

[PROBLEMS] To provide a magnetic head with the high accuracy of the width of a main pole recording magnetic information to a recording medium. [MEANS FOR SOLVING PROBLEMS] A magnetic head is provided with a substrate, a wide part that is provided on the substrate, and a narrow part that is extended from the wide part and is thicker as it separates from the wide part. The magnetic head is characterized in that the narrow part has a magnetic pole having an upper surface and a lower surface having a width that is narrower than the width of the upper surface and is wider as it approaches the wide part, an insulating layer that is provided on the magnetic pole and is non-magnetic and non-conductive, and an auxiliary magnetic pole layer provided on the insulating layer and magnetically connected to the magnetic pole.

Description

Magnetic head, method of manufacturing magnetic head, and magnetic storage device

The present invention relates to a magnetic head capable of writing magnetic information to a magnetic storage medium, a method for manufacturing the magnetic head, and a magnetic storage device including the magnetic head.

In recent years, there has been a remarkable increase in the amount of information handled by computers and communications. There is an increasing demand for a large capacity (high recording density) for a magnetic storage device that records such information. In order to improve the recording density of a magnetic storage device, a magnetic head has been proposed in which the width of the main pole (the width corresponding to the track width in the recording medium) on the air bearing surface (the surface facing the recording medium) of the magnetic head is made smaller. ing. The main magnetic pole has a wide magnetic field guiding portion in which a magnetic field is induced by a coil, a flare portion that is adjacent to the magnetic field guiding portion and becomes narrower as the air bearing surface is approached (so-called tapered shape), and a narrow width that is adjacent to the flare portion And a tip portion. The tip is exposed on the air bearing surface of the magnetic head.

After laminating the various layers that make up the magnetic head, the air bearing surface is usually polished. From the viewpoint of efficiently releasing a magnetic field from the air bearing surface of the magnetic head toward the storage medium, it is preferable that the length of the tip portion (the length in the direction perpendicular to the air bearing surface, so-called “throat height”) is small. Therefore, at present, the tip is polished so that the throat height is about several hundred nm. In order to process the width of the main magnetic pole at the time of this polishing, the tip is usually designed to have a constant width.

However, in the portion where the flare portion and the tip end portion are joined, an inevitable shape distortion resulting from the shape accuracy of the resist used when forming the main magnetic pole occurs. That is, in the vicinity of the joint portion between the tip portion and the flare portion, the width of the tip portion continuously decreases as the distance from the flare portion increases. The width continuously changing in this way is in the range of several hundreds of nanometers from the joint to the air bearing surface. On the other hand, the error in the throat height due to the polishing accuracy is currently about several tens of nm. This polishing accuracy error may cause an error in the main pole width.
JP 2001-76314 A

The present invention provides a structure for making the width of the main pole of a magnetic head for recording magnetic information constant.

According to one aspect of the invention,
A substrate,
A wide portion and a narrow portion that extends from the wide portion and becomes thicker as the distance from the wide portion increases, and the narrow portion is narrower than an upper surface and a width of the upper surface. A magnetic pole having a lower surface with a width that is wider toward
An insulating layer provided on the magnetic pole and nonmagnetic and nonconductive;
There is provided a magnetic head comprising an auxiliary magnetic pole layer provided on the insulating layer and magnetically connected to the magnetic pole.

According to the present invention, a magnetic head having a magnetic pole having a predetermined main magnetic pole width can be obtained even if an error in the range of processing accuracy occurs during polishing of the air bearing surface.

FIG. 1 is a schematic plan view showing a magnetic recording apparatus including a magnetic head obtained according to the present embodiment. FIG. 2 is a schematic view showing a magnetic recording apparatus including the magnetic head obtained according to the present embodiment. FIG. 3 is a cross-sectional view showing a schematic configuration of the first embodiment of the magnetic head. 4A to 4B are sectional views showing a schematic configuration of the first embodiment of the magnetic head. FIG. 5 is a cross-sectional view showing a schematic configuration of the first embodiment of the magnetic head. FIG. 6 is a schematic view showing a cross section of the main magnetic pole layer, which is parallel to the main surface of the substrate, overlaid on the same plane in the first embodiment of the magnetic head. 7A to 7B are partial schematic views of the main magnetic pole layer in the first embodiment of the magnetic head. FIG. 8 is a cross-sectional view of the main magnetic pole layer in the first embodiment of the magnetic head. FIG. 9 is a cross-sectional view showing a schematic configuration of another embodiment of the magnetic head. FIG. 10 is a cross-sectional view showing a schematic configuration of another embodiment of the magnetic head. 11A to 11E are schematic cross-sectional views showing a first embodiment of a method for manufacturing a magnetic head. 12A to 12F are schematic cross-sectional views showing a method for forming a ferromagnetic layer in the first embodiment of the method for manufacturing a magnetic head. FIG. 13 is a perspective view of a ferromagnetic layer obtained by the forming method described with reference to FIG. 13 in the first embodiment of the method of manufacturing a magnetic head. FIG. 14 is a plan view showing an upper surface of the ferromagnetic layer 40, in which a portion T in FIG. 13 is enlarged. 15A to 15D are schematic cross-sectional views showing the process of processing the upper surface of the ferromagnetic layer in the first embodiment of the method of manufacturing the magnetic head. 16A to 16E are partial cross-sectional views showing the ferromagnetic layer after processing the upper surface of the ferromagnetic layer in the first embodiment of the method of manufacturing the magnetic head. 17A to 17B are cross-sectional views showing an example of the cross section of the ferromagnetic layer before processing the upper surface of the ferromagnetic layer in the first embodiment of the method of manufacturing the magnetic head. 18A to 18B are cross-sectional views showing an example of the cross section of the ferromagnetic layer when the upper surface of the ferromagnetic layer is processed in the first embodiment of the method of manufacturing the magnetic head.

Explanation of symbols

7 Substrate 8a to 8d Coil 9

Insulating layer

10A, 10B Connection layer 11 Main magnetic pole layer 12 Insulating layer 13a to 13e Resin layer 14 Trailing shield layer 15 Return yoke layer 16 Air bearing surface 17 Insulating layer 21 Insulating layer 30 Resist layer 31 Resist layer End 40 of the magnetic layer 41 magnetic field induction part 42 flare part 42a tip of the flare part 43 tip part 43a width changing part 43b constant width part 44 main magnetic pole part 45 flare support part 46 wide support part 48 support part 49 inclined surface 50 resist Layer 101 Magnetic disk device 102 Housing 103 Rotating shaft 104 Magnetic disk 105 Head slider 106 Suspension 107 Arm shaft 108 Carriage arm 109 Electromagnetic actuator 110

Controller

111a, 111b Wiring 112 CPU
114 RAM
115 ROM
117 Bus 119 Output Circuit 121 Slider Substrate 122 Magnetic Head 123 Recording Head 124 Playback Head

The configuration of a preferred embodiment of the present invention will be described below with reference to FIGS. 1 to 18 with reference to the drawings.
-Magnetic disk unit-
First, a magnetic disk device as a usage mode of a magnetic head will be briefly described with reference to FIGS. Hereinafter, the same components as those described above are denoted by the same reference numerals. FIG. 1 is a schematic plan view showing a magnetic recording apparatus (hard disk drive: HDD) including a magnetic head obtained according to this embodiment.

The magnetic disk device 101 shown in FIG. 1 has a housing 102 as shown in the figure as an exterior. Inside the housing 102, a magnetic disk 104 mounted on the rotary shaft 103 and rotating in the direction of the arrow 120, a head slider 105 mounted with a magnetic head for recording information on and reproducing information from the magnetic disk 104, A suspension 106 that holds the head slider 105, a carriage arm 108 that is fixed and moves along the surface of the magnetic disk 104 about the arm shaft 107, and an electromagnetic actuator 109 that drives the carriage arm 108 are provided. ing. Note that a cover (not shown) is attached to the housing 102, and the above-described components are accommodated in an internal space formed by the housing 102 and the cover.

The magnetic disk device 1 further includes a control unit 110 that controls the operation of the magnetic disk device 101 as shown in FIG. The control unit 110 is mounted on a control board (not shown) provided inside the housing 102, for example. As shown in FIG. 2, the control unit 110 stores a CPU (Central Processing Unit) 112, a RAM (Random Access Memory) 114 that temporarily stores data processed by the CPU 112, a control program, and the like. A ROM (Read Only Memory) 115, an input / output circuit 119 for inputting / outputting signals to / from the outside, and a bus 117 for transmitting signals between these circuits are included.

As shown in FIG. 2, the head slider 105 has a magnetic head 122 formed on a slider substrate 121. For example, the magnetic head 122 is connected to the input / output circuit 119 in the control circuit 110 by

wirings

111a and 111b, and records information on the magnetic disk 104 (write operation) and reproduces information read from the magnetic disk 104 (read). Operation). When performing this read operation or write operation, the carriage arm 108 is driven by the electromagnetic actuator 109 to move the magnetic head 121 to a desired track on the magnetic disk 104.
-Magnetic head-
3 to 5 are sectional views showing a magnetic head which is a first embodiment of the magnetic head of the present invention. Here, a magnetic head having a recording head portion composed of a single magnetic pole type perpendicular magnetic head is shown. FIG. 3 shows a surface perpendicular to the surface (floating surface) facing the storage medium and perpendicular to the diameter direction of the storage medium. 4A and 4B are plan views showing the air bearing surface. FIG. 5 is a diagram in which cross sections parallel to the main surface of the main magnetic pole layer and the plating base substrate are displayed on the same plane.

In the following description, the X-axis direction is the diameter direction of the storage medium, the Y-axis direction is the direction away from the storage medium, and the Z-axis is the stacking direction of each layer stacked on the substrate (hereinafter referred to as “substrate”). And the moving direction of the medium relative to the magnetic head. The X axis, the Y axis, and the Z axis are perpendicular to each other. Further, the distance in the X-axis direction is expressed as “width”, the distance in the Y-axis direction as “length”, and the distance in the Z-axis direction as “thickness”. In the magnetic head, the side closer to the air bearing surface (air bearing surface: ABS) in the Y-axis direction is referred to as the “air bearing surface side”, and the side away from the air bearing surface is referred to as the “height side”. These notation contents are the same also in FIG.

Hereinafter, the magnetic head according to the first embodiment will be described with reference to FIG. The magnetic head according to the present embodiment is mounted as a magnetic recording device in a magnetic recording apparatus such as a hard disk drive. This magnetic head has an insulating layer 9 made of aluminum oxide (Al ₂ O ₃ ; hereinafter simply referred to as “alumina”) on a substrate 7 made of a ceramic material such as AlTiC (Al ₂ O ₃ TiC). The recording head unit 123 capable of recording information at an arbitrary position on the recording surface of the storage medium by the vertical recording method and an overcoat layer (not shown) made of alumina are stacked in this order. .

An insulating layer 9 is formed on the Altic substrate 7. The insulating layer 9 is made of a nonmagnetic nonconductive material such as alumina. A heater (not shown) may be embedded in the insulating layer 9. The heater heats the recording head unit 111 to expand them and project them to the air bearing surface side. In the magnetic disk device, by controlling the protrusion amount, the flying height can be controlled to be suitable for reproduction and recording.

The recording head portion 123 includes, for example, the main magnetic pole layer 11, the trailing shield layer 14, the connection layers 10A and 10B, the coils 8a to 8d (hereinafter may be collectively referred to as the coil 8), and the resin layers 13a to 13e (hereinafter, referred to as “coil 8”). , And may be collectively referred to as a resist 13), and includes a return yoke layer 15 and insulating

layers

12 and 17.

The main magnetic pole layer 11, the connection layer 10B, the return yoke layer 15, the connection layer 10A, and the trailing shield layer 14 are each made of a magnetic material and are magnetically connected. The portions made of these magnetic materials and the coil 8 are electrically shielded by the insulating

layers

12 and 17 and the resin layer 13. The coil 8, the resist 13, and the connection layer 10A are polished on the surface far from the substrate, and are located on substantially the same plane.

The coils 8a to 8d can generate a magnetic field when energized. The generated magnetic field is guided to the main magnetic pole layer 11 and emitted from the tip of the main magnetic pole layer 11, whereby magnetic information can be recorded on the recording medium. The coils 8a to 8d are made of a conductive material such as copper (Cu), for example. The thickness of the coil is, for example, about 1 to 3 μm. A coil located on the height side of the connection layer 10B is not shown.

The main magnetic pole layer 11 mainly contains magnetic flux generated in the coils 8A and 8B and emits the magnetic flux toward a magnetic disk (not shown). The main magnetic pole layer 11 is normally exposed on the air bearing surface 16 side. The main magnetic pole layer 11 contains a ferromagnetic material. Examples of the ferromagnetic material include iron-cobalt alloy (FeCo), iron-based alloy (Fe-M; M is a metal element of 4A, 5A, 6A, 3B, and 4B group), or nitrides of these alloys. Can be mentioned. The main magnetic pole layer 11 has a thickness of about 0.1 μm to 0.5 μm. The main magnetic pole layer 11 corresponds to a specific example of “magnetic pole” and “magnetic pole layer” in the present invention.

The main magnetic pole layer 11 will be further described with reference to FIGS. 4A and 4B. 4A and 4B are schematic plan views showing the air bearing surface 16, and only the main magnetic pole layer 11 and the trailing shield layer 14 are shown. As shown in FIG. 4A, the cross section on the air bearing surface side of the main magnetic pole layer 11 has an inverted trapezoidal shape. The cross section has such an inverted trapezoidal shape when the magnetic head performs a recording operation depending on the inclination angle (skew angle) of the magnetic head with respect to the circumferential direction (track direction) of the magnetic storage medium. This is to prevent the magnetic pole layer 11 from writing magnetic information on a track that is not desired to be recorded. As shown in FIG. 4B, the cross section on the air bearing surface side of the main magnetic pole layer 11 may be an inverted triangle. The sides of the inverted trapezoid and the inverted triangle are filled with a nonmagnetic insulator such as alumina (not shown).

The main magnetic pole layer 11 will be further described with reference to FIG. FIG. 5 is a schematic view of a cross section of the main magnetic pole layer parallel to the main surface of the substrate. As shown in FIG. 5, the main magnetic pole layer 11 includes a flare portion 42 extending from the magnetic field induction portion 41 and a flare portion tip 42 a on a substrate (not shown) provided with an insulating layer. The magnetic field induction unit 41 is a relatively wide part where a magnetic field for recording by a coil is induced. The width i of the magnetic field guiding part 41 is equal to or greater than the width j of the flare part 42. The width i of the magnetic field induction unit is, for example, several tens of μm. The flare part 42 is a part that narrows down the magnetic field induced by the magnetic field guiding part 41 and guides it to the tip of the flare part. The width j of the flare portion 42 has a so-called taper shape that increases as it approaches the magnetic field guiding portion 41 and decreases as it approaches the tip. The range of the width j of the flare portion is, for example, about 0.1 to 30 μm. The tip 42a of the flare portion is a portion for recording information by emitting a magnetic field from the air bearing surface 16 toward the magnetic storage medium. The width k of the tip of the flare portion is, for example, about several tens to one hundred and several tens of nm. The degree of taper of the tip 42a of the flare part is smaller than that of the flare part 42. The length k ₀ (generally called the throat height) of the tip 42a of the flare part is, for example, a few hundred tens of nm. Of the flare portion, the length j ₀ excluding the tip 42a is, for example, 100 to 150 nm.

In FIG. 5, the ideal shape of the tip 42a of the flare portion is indicated by broken lines R1 and R2. However, inevitable shape curling occurs near the boundary between the flare portion 42 and the tip 42a of the flare portion. This shape distortion is derived from the shape accuracy of the resist layer used when the main magnetic pole layer 11 is formed. A method for forming the resist layer will be described later.

The main magnetic pole layer 11 will be further described with reference to FIG. FIG. 6 is an enlarged perspective view of a portion T surrounded by a dotted line in the main magnetic pole layer 11 shown in FIG. The width of the tip 42a of the flare portion is smaller as it is closer to the substrate 7. For example, the width n ₁ of the upper side of the air bearing surface 16 is larger than the width n ₃ of the lower side. The width n ₂ between the upper side and the lower side is smaller than the width n _{1 and} larger than the width n ₃ . In the range of the air bearing surface 16 to a predetermined length L _C to the magnetic field induction section side, the width of the upper surface of the tip 42a of the flared portion is substantially constant. For example, the width n ₁ of the upper side of the air bearing surface 16 is determined by the width n _1A of the upper side at the position A separated from the air bearing surface 16 by the length L _A and the width n _1B of the upper side at the position B separated by the length L _B. It is equal to the width n _1C of the upper side at the position C separated from the air bearing surface 16 by the length L _C. Also within the air bearing surface 16 to a predetermined length L _C to the magnetic field induction section side, the thickness of the tip 42a of the flared portion is greater as the distance from the magnetic field induction section 41. For example, the thickness h of the flare portion on the air bearing surface 16 is larger than h _{C at} a position C away from the air bearing surface 16 by a length L _C.

The main magnetic pole layer 11 will be further described with reference to FIGS. 7A and 7B. 7A and 7B are schematic views of a portion T surrounded by a dotted line in the main magnetic pole layer 11 shown in FIG. The upper view of FIG. 7A is a top view, and the lower view is a cross-sectional view showing a P ₁ -P ₂ cross section of the upper view. 7B is a cross-sectional view showing a cross section of the main magnetic pole layer 11 in FIG. 7A on the air bearing surface and a cross section parallel to the air bearing surface at position A and position B. As shown in the cross-sectional view of the main magnetic pole layer 11 in FIG. 7B, the width of the tip 42a of the flare portion is smaller as it approaches a substrate (not shown). In other words, the width of the tip 42a of the flare portion is smaller as it approaches the surface in contact with the insulating layer 9 from the surface in contact with the insulating layer 12 in FIG. Further, as shown in the lower part of FIG. 7A, the thickness of the tip 42a of the flare part increases as it approaches the air bearing surface 16, that is, away from the magnetic field guiding part. For example, assuming that the thickness at the air bearing surface 16 is h, the thickness at the position A is h _A , the thickness at the position B is h _B , and the thickness at the position C is h _C , h> h _A > h _B > h _C It is. In addition, the width of the flare portion tip 42a is smaller the closer to the air bearing surface 16, that is, the farther from the magnetic field guiding portion, the inner surface of the flare portion 42a and the distance from the lower surface are the same. For example, as shown in FIG. 7B, on the lower surface of the tip 42a of the flare portion, the width at the air bearing surface is n ₃ , the width at position A is n _3A , the width at position B is n _3B , and the width at position C is n _3C. Then, n ₃ <n _3A <n _3B <n _3C . On the other hand, on the upper surface of the tip 42a of the flare portion, assuming that the width at the air bearing surface is n ₁ , the width at position A is n _1A , the width at position B is n _1B , and the width at position C is n _1C , n ₁ , n _1A , N _1B and n _1C are substantially the same. This is because the tip of the flare part is so small that the width of the tip 42a of the flare part is close to the substrate, is so small that it is far from the magnetic field induction part, and the thickness of the tip 42a of the flare part is so large that it is away from the magnetic field induction part. This can be realized by forming 42a. The magnetic head having the shape of the tip 42a of the flare portion has a main surface on the air bearing surface even if an error in the processing accuracy range occurs when polishing the air bearing surface after laminating the layers constituting the magnetic head. The width of the upper side of the pole layer 11 (so-called main pole width) is constant. That is, a magnetic head satisfying a predetermined main magnetic pole width can be obtained even if polishing is performed more excessively than the current air bearing surface 16.

8 is a cross-sectional view showing an example of a cross section parallel to the air bearing surface of the tip 42a of the flare portion and the air bearing surface at the position B. FIG. In FIG. 8, the cross section PQRS at the air bearing surface 16 and the cross section P _A Q _A R _A S _{A at} the position A are displayed in an overlapping manner. For example, as shown in FIG. 8, the side PQ and the side P _A Q _A are parallel to the air bearing surface 16 of the tip 42a of the flare portion and the cross section at the position A. Further, the side RS and the side R _A S _A are parallel. In this way, when the air bearing surface 16 and the corresponding side of the cross section at the position A are parallel to each other, the thickness h _A at the position _A is the taper angle θ, the angle α formed by the upper side and the side, The thickness h, the width n ₃ of the lower side of the air bearing surface 16, and the width n _3A of the lower side at the position A are expressed by the following formula (1).

h _A = h− (n _3A −n ₃ ) / 2 tan θ
= H- (n _3A -n ₃ ) / 2 tan (90 ° -α) (1)
When the relationship of the following formula (1) is satisfied, the width n ₁ of the upper side on the air bearing surface is equal to the width n _1A of the upper side at the position A. A similar relationship holds between the air bearing surface 16 and the cross section at position B, and the air bearing surface 16 and the cross section at position C.

Referring to FIG. 3 again, the magnetic head according to the first embodiment will be described.

The plating base (not shown) is located on the substrate side of the main magnetic pole layer 11. This is a layer that functions as an electrode when the main magnetic pole layer 11 is formed by a plating method. The plating base can be made of any material having conductivity. The material contained in the plating base is selected from at least one of tantalum (Ta), titanium (Ti), ruthenium (Ru), and the like. If the main magnetic pole layer 11 is not formed using the plating method, the plating base is not provided.

The trailing shield layer 14 mainly uses the magnetic field gradient of the write magnetic field of the main magnetic pole layer when the magnetic flux emitted from the main magnetic pole layer 11 is circulated to the return yoke layer 15 via the hard disk (not shown). Takes the function of sharpening. The trailing shield layer 14 also has a function of magnetically shielding the main magnetic pole layer 11 from the surroundings. The trailing shield layer 14 is normally exposed on the air bearing surface 16 side. The trailing shield layer 14 is made of a magnetic material such as permalloy (Ni: 80 wt%, Fe: 20 wt%), and has a thickness of about 1.0 μm to 2.0 μm. Here, the trailing shield layer 14 corresponds to a specific example of the “auxiliary magnetic pole layer” in the present invention.

The return yoke layer 15 has a function of circulating the magnetic flux emitted from the main magnetic pole layer 11 through the hard disk (not shown) in the recording head unit 111. The return yoke layer 15 is made of, for example, a magnetic material such as permalloy (Ni: 80 wt%, Fe: 20 wt%), and has a thickness of about 1.0 μm to 4.0 μm. The return yoke layer 15 corresponds to a specific example of “auxiliary magnetic pole layer” in the invention.

The resin layers 13a to 13e are made of, for example, a photoresist (photosensitive resin) that exhibits fluidity when heated. In the resin layers 13a to 13e, ceramics such as alumina may be disposed instead of the resin layers 13a to 13e. Here, the resin layers 13a to 13e correspond to a specific example of “insulating layer” in the present invention.

The insulating layer 12 is made of a material that can ensure electrical insulation between the coil 8 and the main magnetic pole layer 11 and is nonmagnetic. The insulating layer 12 is made of a nonmagnetic nonconductive material such as alumina or silicon oxide (SiO ₂ ). Further, a nonmagnetic material having conductivity such as ruthenium (Ru) or copper (Cu) may be used on the air bearing surface side of the insulating layer 12. The insulating layer 12 has a thickness of about several tens to several hundreds of nanometers on the air bearing surface side and about 0.1 μm to 1.0 μm on the height side. The insulating layer 12 may be composed of a plurality of materials, or may be composed of a plurality of layers made of different materials. Here, the insulating layer 12 corresponds to a specific example of “insulating layer” in the present invention.

The insulating layer 17 is provided so as to cover the coil 8 and the resin layer 13. The insulating layer 17 is made of a nonmagnetic nonconductive material such as alumina, silicon oxide (SiO ₂ ), or photoresist, and has a thickness of about 0.1 μm to 1.0 μm, for example. When the insulating layer 17 is made of a photoresist, it is usually formed integrally with the resin layer 13. Here, the insulating layer 12 corresponds to a specific example of “insulating layer” in the present invention.

The connection layer 10A is for magnetically connecting the return yoke layer 15 and the trailing shield 14, and is usually located on the air bearing surface side of the coil 8. The connection layer 10 </ b> B is for magnetically connecting the return yoke layer 15 and the main magnetic pole layer 11, and is usually located on the height side of the coil 8. The connection layers 10A and 10B are made of a magnetic material such as permalloy (Ni: 80% by weight, Fe: 20% by weight). The connection layer 10A corresponds to a specific example of “auxiliary magnetic pole layer” in the invention.

An overcoat layer (not shown) is provided on the upper surface of the recording head unit 123 in order to protect the recording head unit 123. The material constituting the overcoat layer is not particularly limited. The overcoat layer can be made of alumina, for example.

Each of the above layers uses, for example, an existing thin film process including a film forming technique such as plating or sputtering, a patterning technique using a photolithography method or an etching method, and a polishing technique such as machining or polishing, It can be manufactured by laminating on a substrate 7 made of a ceramic material in order from the lower layer to the upper layer in FIG. Details of the method of manufacturing the magnetic head will be described later.

When the magnetic head 122 is disposed on a magnetic disk and information is to be recorded on the recording layer on the storage medium, a predetermined magnetic flux is generated by passing a current through the coil 8 near the main magnetic pole layer 11. The magnetic flux generated by the coil 8 passes through the main magnetic pole layer 11 and flows from the air bearing surface 16 to the surface of the storage medium (not shown). The magnetic field flowing into the recording layer flows out into the magnetic flux and flows into the trailing shield layer 14, the connection layer 10 </ b> A, and the return yoke layer 15. A magnetic circuit is formed by the main magnetic pole layer 11, the storage medium (not shown), the trailing shield layer 14, the connection layer 10A, the return yoke 15, and the connection layer 10B. Using this magnetic circuit, magnetization (information) in a direction perpendicular to the storage medium surface of the storage medium can be recorded on the recording layer. In the magnetic head, the main magnetic pole width is constant even when an error in the range of processing accuracy occurs when the air bearing surface side is polished after laminating the layers constituting the magnetic head. That is, even if the air bearing surface 16 is excessively polished, a magnetic head satisfying a predetermined main pole width can be obtained.

9 and 10 are cross-sectional schematic views showing different embodiments of the magnetic head of the present invention. 9 and 10 are schematic plan views showing a surface (floating surface) facing the storage medium. In these magnetic heads, the cross section of the main magnetic pole layer parallel to the air bearing surface and the cross section of the main magnetic pole layer parallel to the main surface of the substrate are the same as the cross sectional shapes described with reference to FIGS. Therefore, it is omitted. In the magnetic head of the above embodiment, the trailing shield layer 14 and the connection layers 10A and 10B are provided. For example, as shown in FIG. 9, the trailing shield 14 and the connection layers 10A and 10B are not provided. good.

The magnetic head of the present invention may be a composite head capable of performing both recording and reproduction functions. For example, as shown in FIG. 10, an insulating layer 9 and a reproduction head portion are formed on a substrate 7. 124, the recording head part 123, and the overcoat layer (not shown) may be laminated in this order. For example, the reproducing head unit 124 has a configuration in which the lower shield layer 3, the gap film 4, and the upper shield layer 6 are laminated in this order. In the gap film 4, a magnetoresistive effect element (Magnetorescence effect element, hereinafter abbreviated as MR element) 5 is embedded so that one end face is exposed on the air bearing surface 16.

The lower shield layer 3 and the upper shield layer 6 mainly shield the MR element 5 from the surroundings. The lower shield layer 3 and the upper shield layer 6 are made of, for example, a magnetic material such as a nickel iron alloy (NiFe (hereinafter simply referred to as “permalloy (trade name)”); Ni: 80 wt%, Fe: 20 wt%). Their thickness is about 1.0 μm to 2.0 μm.

The gap film 4 electrically isolates the MR element 5 from the lower shield layer 3 and the upper shield layer 6. The gap film 4 is made of, for example, a nonmagnetic nonconductive material such as alumina and has a thickness of about 0.1 μm to 0.2 μm.

As the MR element 5, for example, an element using a magnetosensitive film exhibiting a magnetoresistive effect such as a giant magnetoresistive effect (GMR; Giant Magneto-resistive) or a tunnel magnetoresistive effect (TMR; Tunneling Magneto-resistive) can be used. .

The magnetic head shown in FIGS. 9 and 10 has an error in the processing accuracy range when the air bearing surface side is polished after laminating each layer constituting the magnetic head, like the magnetic head shown in FIGS. Even if it occurs, the main pole width is constant. That is, even if the air bearing surface 16 is excessively polished, a magnetic head including a main magnetic pole layer having a predetermined main magnetic pole width can be obtained.
-Magnetic head manufacturing method-
FIGS. 11A to 11E are schematic cross-sectional views showing a first embodiment of the method for manufacturing a magnetic head of the present invention. In the process of manufacturing a magnetic head having the same configuration as the magnetic head described with reference to FIGS. 5 is a schematic cross-sectional view showing a cross-sectional shape corresponding to the air bearing surface of the finally obtained magnetic head in the laminated body in FIG. In addition, description is abbreviate | omitted about the part which overlaps with description of the magnetic head of the said embodiment.

First, as shown in FIG. 11A, an insulating layer (not shown) such as alumina is formed on a substrate 7 such as Altic, and a plated base layer (such as ruthenium) is formed on the substrate 7 on which the insulating layer is formed. (Not shown) is formed by sputtering or the like. Next, as shown in FIG. 11B, the ferromagnetic layer 40 is formed on the substrate 7 provided with an insulating layer and a plating base layer (not shown). The ferromagnetic layer 40 becomes the main magnetic pole layer 11 in the finally obtained magnetic head.

12A to 12F are schematic cross-sectional views showing a method for forming the ferromagnetic layer 40. FIG. This schematic cross-sectional view shows a cross-section at the tip of the main magnetic pole layer 11 (that is, a cross-section corresponding to the air bearing surface in the obtained magnetic head).

First, as shown in FIG. 12A, a resist layer 30 is applied to the surface of the substrate 7. The resist used may be positive or negative. Subsequently, as shown in FIG. 12B, the resist layer 30 is patterned by using a normal photolithography technique. Specifically, for example, after exposure is performed with an exposure mask disposed on the resist layer 30, the exposed portion of the resist layer 30 is removed by development. This mask is an opening-type mask having an opening reflecting the pattern shape of the main magnetic pole layer 11 finally obtained when viewed in the direction of the main surface of the substrate 7. The exposure apparatus (exposure conditions) to be used and the type of developer can be arbitrarily set. The end part (edge) 31 of the resist layer 30 after development rises substantially vertically as shown in FIG. 12B. After the development, the width of the opening 32 of the resist layer is larger as the distance from the air bearing surface is closer to the magnetic field guiding portion within a predetermined distance from the cross section corresponding to the air bearing surface. When this resist layer 30 is put into a heating furnace at a predetermined temperature and the resist layer 30 is reflowed (fluidized), a resist layer 30 having a tapered end 31 as shown in FIG. 12C can be obtained. After reflow, the taper angle at the end of the resist layer 30 is usually constant in a cross section parallel to the cross section corresponding to the air bearing surface. At this time, the width of the opening 32 of the resist layer is increased as the distance from the air bearing surface in the direction approaching the magnetic field guiding portion is within a predetermined distance from the cross section corresponding to the air bearing surface. Next, as shown in FIG. 12D, the tapered resist layer 30 is plated with a ferromagnetic material (for example, permalloy) to form the ferromagnetic layer 40. After removing the resist layer 30 as shown in FIG. 12E, the ferromagnetic layer 40 is slimmed by ion milling as shown in FIG. 12F. In FIG. 12F, the shape of the ferromagnetic layer 40 maintains an inverted trapezoidal shape, but becomes an inverted triangle as described above when the width of the tip is smaller or when ion milling is performed more. In the manufacturing flow shown in FIGS. 12A to 12F, not only the side surface but also the upper surface of the pattern formed by ion milling (plating pattern made of a ferromagnetic material) is etched by ions, so that the pattern thickness (that is, the plating thickness) is also increased. Will be reduced.

FIG. 13 is a perspective view of a ferromagnetic layer obtained by the formation method described with reference to FIGS. 12A to 12F. FIG. 13 shows a pattern of the ferromagnetic layer formed on the plating base layer that is not yet completed as a magnetic head. The ferromagnetic layer 40 includes a main magnetic pole portion 44 that becomes the main magnetic pole layer 11 in the obtained magnetic head, and a support portion 48 that is integrated with the main magnetic pole portion 44 in order to maintain the shape of the main magnetic pole portion 44 during manufacturing. And comprising. The main magnetic pole part 11 includes a magnetic field guiding part 41, a flare part 42, and a part of the tip part 43. The magnetic field guiding part 41, the flare part 42, and the tip part 43 are magnetically connected. The width i (the length in the X-axis direction) in the cross section perpendicular to the stacking direction of the magnetic field induction part 41 is equal to or greater than the width j of the flare part 42. In the magnetic field induction unit 41, a magnetic field is induced by a coil (not shown). The flare part 42 is adjacent to the magnetic field induction part 41 and the tip part 43. The width j of the flare portion 42 has a tapered shape that becomes narrower as it approaches the tip portion 43 from the magnetic field guiding portion 41. The tip portion 43 is adjacent to the flare portion 42. The tip portion 43 usually has a substantially constant width k except for the end portion in the longitudinal direction for convenience of processing the magnetic pole width to be constant. The width k of the tip portion 43 is equal to or less than the width j on the height side of the flare portion 42. Near the boundary between the flare portion 42 and the tip portion 43 (the end portion in the longitudinal direction of the tip portion 43), an inevitable shape distortion resulting from the shape accuracy of the resist layer 30 in FIG. 12C occurs. Therefore, the width of the end portion 43 near the flare portion 42 gradually decreases with increasing distance from the magnetic field guiding portion 41, like the shape of the flare portion tip 42a described with reference to FIGS. The support portion 48 is provided for the purpose of preventing the tip of the flare portion 42, which is narrow and high in height compared to the width, and the tip portion 43 from falling or bending during the manufacture of the magnetic head. The support part 48 and the magnetic field induction part 41 are provided so as to sandwich the flare part 42 and the tip part 43. That is, the support portion 48 and the magnetic field guiding portion 41 are formed in a pattern so as to support the flare portion 42 and the tip portion 43. The shape of the support portion 48 is not particularly limited as long as this object can be achieved. For example, a shape constituted by a flare support portion 45 having a tapered shape and a wide support portion 46 as in the present embodiment is adopted. can do. The width q of the flare support portion 45 is not less than the width k of the tip portion 43 and not more than the width m of the wide support portion 46.

The width i of the magnetic field induction unit 41 is, for example, about several tens of μm. The range of the width j of the flare portion 42 is, for example, about 0.1 to 30 μm. The width k of the distal end portion 43 is, for example, about several tens to one hundred and several tens of nm. The range of the width q of the flare support portion 45 is, for example, about 0.1 to 10 μm. The length q _z of the flare support portion 45 is, for example, 100 to 150 nm. The width r of the wide support portion 46 is, for example, about 5 to 10 μm. In the present embodiment, the width i of the magnetic field guiding part 41 is larger than the width r of the wide support part 46, but the width r of the wide support part 46 may be larger than the width i of the magnetic field guiding part.

The length k _{z of the} bridge formed by the tip portion 43 is, for example, 1 to 2 μm. In the post process, the main magnetic pole layer 11 having a predetermined throat height can be obtained by polishing the ferromagnetic layer 40 from the support portion 48 side to a cross section perpendicular to the Y axis passing through the line segment E ₁ -E _2. it can. A cross section perpendicular to the Y-axis passing through the line segment E ₁ -E ₂ constitutes a part of the air bearing surface of the magnetic head.

FIG. 14 is a plan view showing the upper surface of the ferromagnetic layer 40 in which the portion T in FIG. 13 is enlarged. The shape near the boundary between the flare portion 42 and the tip portion 43 is not linear as shown by the solid line. This originates in the shape of the resist layer 30 in the method for forming a ferromagnetic layer described with reference to FIGS. 12A to 12F. The resist layer 30 is formed by an exposure mask having a shape corresponding to a linear shape as indicated by dotted lines R1 and R2 in FIG. However, the shape of the resist layer 30 in the vicinity of the boundary between the flare portion 42 and the tip portion 43 is not linear due to the influence of light wrapping during exposure. The length of the width changing portion 43a in the Y-axis direction is currently about several hundreds of nm.

11A to 11E again, the method for manufacturing the magnetic head of this embodiment will be described. Then, the insulating layer 21 is provided so as to cover the ferromagnetic layer 40, and the stacked body shown in FIG. 11C is obtained. The insulating layer 21 is made of a nonmagnetic nonconductive material such as alumina. The insulating layer 21 can be formed by sputtering, for example. Next, as shown in FIG. 11D, the upper surface of the insulating layer 21 is polished by CMP until the ferromagnetic layer 40 is exposed and the upper surface becomes flat.

Next, the upper surface of the ferromagnetic layer 40 is processed so that the thickness increases as the distance from the magnetic field guiding portion 41 increases. 15A to 15D are schematic cross-sectional views showing a process of processing the upper surface of the ferromagnetic layer. FIG. 15A is a partial cross-sectional view showing a cross-sectional shape passing through F ₁ -F ₂ of the ferromagnetic layer shown in FIG. 13 and perpendicular to the X-axis. Of the upper surface of the ferromagnetic layer 40, the part that can be processed is a part that becomes wider as it moves away from the magnetic field guiding part 41, that is, the part that is close to the flare part 42 among the flare part 42 and the tip part 43. 43a (hereinafter referred to as the width changing portion 43a). First, as shown in FIG. 15B, a patterned resist layer 50 is provided on the upper surface of the ferromagnetic layer 40. Of the upper surface of the ferromagnetic layer 40, the resist layer 50 is not provided on the portion to be processed. The resist layer 50 can be formed using a normal photolithography technique. Details of the resist layer 50 are the same as those of the resist layer 30 in FIG. Thereafter, the ferromagnetic layer 40 exposed in the portion 51 where the resist is not provided is removed by etching such as ion milling, and a step is formed on the upper surface of the ferromagnetic layer 40 as shown in FIG. 15C. At this time, the resist layer 50 becomes a shadow with respect to the ion beam emitted in the ion milling to the ferromagnetic layer 40. Therefore, by controlling the resist shape or the ion beam incident angle, the thickness of the ferromagnetic layer 40 continuously changes in the direction extending from the magnetic field guiding portion (not shown) toward the flare portion 42. As described above, the upper surface of the ferromagnetic layer 40 can be processed. For example, by adjusting the thickness of the resist layer 50 and the taper angle of the sidewall of the resist layer 50, the thickness of the portion U near the resist layer 50 and the gradient of the upper surface of the exposed upper surface of the ferromagnetic layer 40 can be arbitrarily controlled. Can do. Thereafter, as shown in FIG. 15D, the resist layer 50 is removed.

It should be noted that the shape of the step is not limited to the shape shown in FIG. 16A to 16E are partial cross-sectional views showing the ferromagnetic layer after processing the upper surface of the ferromagnetic layer. For example, as shown in FIG. 16A, a portion U in which the thickness and the gradient of the upper surface are controlled may be provided across the flare portion 42 and the width changing portion 43a. Further, as shown in FIG. 16B, the portion U may be provided in the flare portion 42.

Further, as shown in FIG. 16C, a portion V that increases in thickness as it approaches the magnetic field guiding portion 41 may be provided on the magnetic field guiding portion 41 side of the portion U provided in the width changing portion 43a. In a magnetic disk device, data on a magnetic recording medium is read and written by a magnetic head. In order to increase the recording capacity per unit area of the magnetic recording medium, the density in both the track width direction (magnetic pole width direction: X-axis direction) and the bit length direction (magnetic pole thickness direction: Z-axis direction) is improved. There is a need. When the track width is reduced, it is necessary to reduce the main pole width. However, when the main magnetic pole width is reduced, the output of the recording magnetic field induced from the main magnetic pole layer to the magnetic recording medium is reduced. Therefore, there is a concern that a write failure may occur due to a decrease in the recording magnetic field output from the main magnetic pole. The portion V whose thickness increases as it approaches the magnetic field guiding portion 41 has a function of compensating for the output of the recording magnetic field that has been lowered by reducing the main magnetic pole width and avoiding the occurrence of write defects. As shown in FIG. 16D, the portion U may be provided across the flare portion 42 and the width changing portion 43a, and further, the portion V may be provided on the magnetic field guiding portion 41 side of the portion U. Further, as shown in FIG. 16E, the portion U may be provided in the flare portion 42, and the portion V may be further provided on the magnetic field induction portion 41 side of the portion U. The ferromagnetic layers having the shapes shown in FIGS. 16A to 16E can be formed by changing the shape of the resist layer.

The process of processing the top surface of the magnetic pole using the ion milling will be further described with reference to FIGS. 17A to 17B. 17A to 17B are schematic partial cross-sectional views showing an example of the ferromagnetic layer before processing the upper surface of the ferromagnetic layer. FIG. 17A is a cross section obtained by enlarging the portion T in FIG. 13 and parallel to the main surface of the substrate. FIG. 17B is a cross section parallel to the Y axis (parallel to the air bearing surface) in FIG. 17A. In the polishing process for forming the air bearing surface 16 to be described later, the polishing error is assumed to be f. The length of the upper side of the cross section perpendicular to the Y axis at the position f / 2 (position D) from the processing target position M toward the constant width portion 43b is defined as d. A length e of the upper side at a position (position E) of f / 2 from the position M toward the magnetic field guiding section (not shown). Let p be the length of the upper side of the cross section perpendicular to the Y axis at an arbitrary position P between the position D and the position E. The length of the upper side satisfies the relationship d <p <e. The taper angle of the cross section parallel to the Y axis between the position D and the position E of the ferromagnetic layer 40 is θ (constant) (the angle between the upper side and the side side in the cross section is α (constant)). . Further, it is assumed that corresponding side edges at positions D, E, and P are parallel to each other. Before the upper surface of the ferromagnetic layer 40 is processed, the thickness of the ferromagnetic layer 40 between the position D and the position E is set to h _D. Now, let the target main pole width be d.

FIG. 18A is a schematic diagram in which the cross sections of the ferromagnetic layer 40 perpendicular to the Y axis at the positions D and P are overlapped. The depth to be removed on the basis of the upper surface of the position P before processing is defined as h ₁ , and the thickness of the position P after processing of the upper surface is defined as h _P.

From the geometrical relationship of the cross-sectional shape of the ferromagnetic layer 40 shown in FIG. 18A, the ferromagnetic layer 40 is removed so as to satisfy the relationship of the following formula (2) at an arbitrary position P between the position D and the position E. By doing so, the width of the upper side of an arbitrary cross section perpendicular to the Y axis between the position D and the position E can be made constant.

h ₁ = (pd) / 2 tan θ
= (Pd) / 2 tan (90 ° -α) (2)
The shape of the resist layer 50 necessary to satisfy the above formula (2) will be described with reference to FIG. 18B. As shown in FIG. 18B, the upper surface of the ferromagnetic layer 40 that satisfies the condition of the above formula (2) is adjusted by adjusting the taper angle φ and the film thickness m of the resist layer 50 used as a mask during ion milling. It can be arbitrarily formed.

An example of processing the upper surface of the ferromagnetic layer 40 is shown below. First, by the known method, a ferromagnetic material (e.g., permalloy) a thickness h _D is 300 nm, the taper angle θ formed the ferromagnetic layer 12 °. An error f of polishing performed to form the air bearing surface 16 described later was 40 nm. Therefore, the distance between the position D and the position E in FIG. The width of the upper side of the cross section perpendicular to the Y axis of the ferromagnetic layer 40 at the position D and the position E was 176 nm and 191 nm, respectively, as measured with a scanning electron microscope. Therefore, the required height difference h ₂ between the positions DE was calculated as follows.

h ₂ = (191 nm-178 nm) / ₂ tan 12 ° = 35.3 nm
Next, a resist is applied on the ferromagnetic layer 40, exposed, and developed, thereby forming a resist layer 50 having an inversely tapered shape. In this experimental example, the resist layer 50 having a resist film thickness m of 3500 mm and a taper angle φ of 8 ° was formed by using electron beam lithography capable of easily forming a reverse taper pattern. Next, the inclined surface 49 was formed by performing ion milling on the upper surface of the ferromagnetic layer 40 on which the resist layer 50 was formed. The height difference h ₂ on the upper surface of the ferromagnetic layer 40 at the positions D and E was measured using a scanning electron microscope to be 37 nm.

11A to 11E again, the method for manufacturing the magnetic head of this embodiment will be described. Thereafter, as shown in FIG. 11E, the insulating layer 12 and the trailing shield layer 14 are sequentially formed on the upper surface of the laminate. In addition, although not shown in the drawing, a coil (not shown), a resin layer (not shown), and an insulating layer (not shown) provided so as to cover the coil and the resin layer are located at the back of FIG. 11D. Is provided. Here, the coil corresponds to the coil 8 in FIG. 3, the resin layer corresponds to the resin layer 13 in FIG. 3, and the insulating layer corresponds to the insulating layer 17 in FIG. Further, in order to magnetically connect the trailing shield layer 14 and the ferromagnetic layer 40, layers (not shown) corresponding to the connection layers 10A and 10B and the return yoke layer 15 shown in FIG. 3 are provided. These layers use, for example, existing thin film processes including film formation techniques such as plating and sputtering, patterning techniques utilizing photolithography and etching, and polishing techniques such as machining and polishing. It is possible to form. Next, an overcoat layer (not shown) is provided on the entire upper surface by sputtering.

Thereafter, the obtained multilayer body is polished from the support portion 48 side of the ferromagnetic layer 40 in FIG. 13 to a position corresponding to a cross section perpendicular to the Y axis passing through the line segment E ₁ -E ₂ . By this polishing, a magnetic head including the main magnetic pole layer 11 having the shape described with reference to FIGS. 3 to 8 can be obtained. By this polishing, the air bearing surface 16 in FIGS. 3 to 7 is formed. The polishing means is not particularly limited, and examples thereof include polishing using a dicing saw. Note that after cutting the substantially parallel arbitrary cross section to line _E 1 -E ₂ of the supporting portion 48 in FIG. 13, through the line _E 1 -E ₂ from the support portion 48 side of the ferromagnetic layer 40 in FIG. 13 The ferromagnetic layer 40 may be polished to a position corresponding to a cross section perpendicular to the Y axis. In this polishing process, even if an error within the range of processing accuracy occurs, the width of the main magnetic pole layer 11 in the vicinity of the air bearing surface is substantially constant. Therefore, according to the magnetic head manufacturing method of the present embodiment, a magnetic head including a main magnetic pole layer having a desired main magnetic pole width can be manufactured with high accuracy.

The present invention is not limited to the above embodiment. The above-described embodiment is an exemplification, and the present invention has any configuration that has substantially the same configuration as the technical idea described in the claims of the present invention and that exhibits the same effects. Are included in the technical scope.

Claims

A substrate,
A wide portion and a narrow portion that extends from the wide portion and increases in thickness as the distance from the wide portion increases. The narrow portion is narrower than the upper surface and the width of the upper surface. A magnetic pole having a lower surface with a width that is wider toward
An insulating layer provided on the magnetic pole and nonmagnetic and nonconductive;
A magnetic head having an auxiliary magnetic pole layer provided on the insulating layer and magnetically connected to the magnetic pole.
The magnetic head according to claim 1, wherein an upper surface of the narrow portion has a substantially constant width.
The magnetic head according to claim 1, wherein the magnetic pole is made of a ferromagnetic material.
In a cross section of the narrow portion perpendicular to the extending direction of the narrow portion and the wide portion, an angle formed by an upper side on the first surface and a side side adjacent thereto is α (°), and the narrow portion When the thickness of the end portion is h the width of the lower edge on the second surface and n 3, the height h a is represented by the following formula for any cross-section of the constriction width of the lower edge is n 3A: (1) The magnetic head according to claim 1, wherein the magnetic head is satisfied.
h A = h− (n 3A −n 3 ) / 2 tan (90 ° −α) (1)
The magnetic head according to claim 1, wherein the narrow portion has a portion that increases in thickness as it approaches the wide portion.
Forming a pole layer on the substrate;
The magnetic pole layer includes a wide portion and a narrow portion extending from the wide portion, and is processed so that the width of the narrow portion is narrower as it is closer to the substrate and the width of the narrow portion is wider as it is closer to the wide portion. And a process of
Processing the upper surface of the narrow portion so that the thickness of the narrow portion becomes thicker as the distance from the wide portion increases.
Forming a nonmagnetic and nonconductive insulating layer on the pole layer;
Forming an auxiliary magnetic pole layer magnetically connected to the magnetic pole layer on the insulating layer.
The step of processing the upper surface of the narrowed portion is a step of processing the upper surface of the narrowed portion so that the thickness of the narrowed portion increases as the distance from the widened portion increases and the width of the narrowed portion becomes substantially constant. The method of manufacturing a magnetic head according to claim 6.
The method of manufacturing a magnetic head according to claim 6, wherein, in the step of processing the upper surface of the narrow portion, the upper surface of the narrow portion is processed by etching.
The step of processing the upper surface of the narrow portion includes a step of forming a resist pattern on the narrow portion and a step of etching the upper surface of the narrow portion using ion milling. 6. A method of manufacturing a magnetic head according to 6.
In the step of processing the upper surface of the narrow portion, in the cross section perpendicular to the extending direction of the narrow portion and the wide portion, an angle formed by the upper side and the adjacent side side is α (°), and the target length of the upper side is When the thickness is a, the narrow portion having an upper side length of b includes a step of processing so that the thickness is reduced by (ba) / tan (90 ° -α). A method of manufacturing the magnetic head according to claim 6.
The magnetic head manufacturing method according to claim 6, wherein the step of processing the upper surface of the narrow portion further includes a step of forming a portion in which the thickness of the narrow portion increases as the width portion approaches the wide portion. Method.
A substrate,
A wide portion and a narrow portion that extends from the wide portion and increases in thickness as the distance from the wide portion increases. The narrow portion is narrower than the upper surface and the width of the upper surface. A magnetic pole having a lower surface with a width that is wider toward
An insulating layer provided on the magnetic pole and nonmagnetic and nonconductive;
A magnetic head having an auxiliary magnetic pole layer provided on the insulating layer and magnetically connected to the magnetic pole;
A magnetic storage device comprising: a magnetic storage medium facing the magnetic head and capable of recording magnetic information by a magnetic field applied from the magnetic head.