WO2000017861A1

WO2000017861A1 - Thin film induction write magnetic head and method of manufacturing the same

Info

Publication number: WO2000017861A1
Application number: PCT/JP1999/000331
Authority: WO
Inventors: Tomoko Kutsuzawa; Ikuya Tagawa; Syuji Nishida
Original assignee: Fujitsu Limited
Priority date: 1998-09-18
Filing date: 1999-01-27
Publication date: 2000-03-30
Also published as: JP2000099918A

Abstract

A thin film induction write magnetic head has an upper magnetic layer (28) and a lower magnetic layer (29). In the tip of the magnetic head is formed a gap layer (39) between narrow, small upper and lower sub-magnetic poles (35, 36). By restricting the shape including the length (GD) in the direction vertical to the flying surface of the upper sub-magnetic pole, the magnetic field generated around the edge (28a) of the upper magnetic layer overhanging from the upper sub-magnetic pole in the direction of the width of the recording track is weakened. Because of the weakening, the width of the recording track is narrowed and the recording blur is relieved, thus providing a thin film induction write magnetic head having good magnetic field characteristics suitable for improving the surface recording density.

Description

Description Thin-film inductive write magnetic head and method for manufacturing the same

The present invention relates to a thin-film inductive write magnetic head including an upper magnetic pole layer facing the air bearing surface, and a lower magnetic pole layer facing the upper magnetic pole layer with the gap layer interposed therebetween and facing the air bearing surface. Formed at the boundary between the gap layer and the air bearing surface, and swells toward the lower pole layer along the air bearing surface, and formed on the lower magnetic pole layer along the air bearing surface from the boundary surface with the gap layer. The present invention relates to a thin-film inductive write magnetic head further comprising a lower sub-pole bulging toward the upper sub-pole. Background art

The upper magnetic pole layer and the lower magnetic pole layer facing each other with the gap layer interposed therebetween form a write gap on the air bearing surface of the magnetic head slider. In this writing gap, lines of magnetic force passing between the two magnetic pole layers bypass the gap layer and act on the recording medium facing the air bearing surface to magnetize the recording medium. This magnetization generates a recording track on the recording medium.

The width of the upper magnetic pole layer and the lower magnetic pole layer facing each other on the air bearing surface determines the recording track width. If the widths of the upper magnetic pole layer and the lower magnetic pole layer can be reduced, it is possible to increase the track density and to further improve the areal recording density. Therefore, if a narrow upper sub-pole swelling from the upper pole layer to the lower pole layer and a narrow lower sub-pole swelling from the lower pole layer to the upper pole layer are used, a narrow writing gap can be obtained. It is thought that the surface recording density can be increased as a result.

However, in a magnetic head having an upper sub-pole and a lower sub-pole, not only a magnetic field peak occurs at a write gap used for recording information, but also the recording track extends from the upper sub-pole along the air bearing surface in the recording track width direction. A magnetic field peak also occurs at the edge of the upper magnetic pole layer. The magnetic field beak caused by these edges is The recording track adjacent to the recording track on which information is recorded is disturbed. Unless the peak of the magnetic field generated in such an edge is suppressed, the areal recording density on the recording medium cannot be increased as desired. Disclosure of the invention

The present invention has been made in view of the above situation, and has as its object to provide a thin-film inductive write magnetic head having good magnetic field characteristics suitable for improvement in areal recording density. To achieve the above object, according to the present invention, an upper magnetic pole layer facing the air bearing surface, a lower magnetic pole layer facing the upper magnetic pole layer with the gap layer interposed therebetween and facing the air bearing surface, and an upper magnetic pole layer are formed. And an upper sub-pole swelling from the boundary surface with the gap layer along the air bearing surface toward the lower magnetic pole layer, and the vertical length of the upper sub-magnetic pole in the air bearing surface is set to 1.5 m or more. A thin-film inductive write magnetic head is provided.

According to such a thin-film inductive write magnetic head, a narrow gap layer force is formed between the upper sub pole and the lower pole layer. The recording track width of the recording medium on which the magnetic head records information is determined by the narrow gap layer. Therefore, the width of the recording track can be made narrower than simply using the gap layer formed by the upper magnetic pole layer and the lower magnetic pole layer. As a result, the track density can be increased, and the areal recording density of the recording medium can be further improved.

In the magnetic head, since the boundary surface of the upper magnetic pole layer protrudes from the upper sub magnetic pole in the recording track width direction along the air bearing surface, good overwrite characteristics can be obtained. In addition, if the vertical length of the air bearing surface of the upper sub magnetic pole is set to 1.5 m or more, the magnitude of the magnetic field generated at the edge of the overhanging upper magnetic pole layer can be reliably reduced by the coercive force H c of the recording medium. It can be reduced to less than one part. If the magnetic field strength of the applied magnetic field is equal to or less than half of the coercive force Hc, it is considered that no reversal of the magnetization occurs on the recording medium. As a result, it is possible to avoid problems such as an increase in the recording track width and a magnetization reversal of a recording track adjacent to a recording track on which information is recorded.

In addition, if the vertical length of the air bearing surface is set to 3.0 Om or more, even if the overhang length of the upper pole layer overhanging from the upper sub-pole is large, the magnitude of the magnetic field generated by the edge is sufficiently prevented. The magnetic force H c can be reduced to less than half. Thus the top If the overhang length of the magnetic pole can be increased, the yield during manufacturing can be improved. However, if the overhang length is large, the magnetic field generated at the edge increases, so the overhang length of the upper pole layer is preferably 0.4 or less.

The thin-film inductive write magnetic head may further include a lower sub-pole formed on the lower pole layer and swelling from the interface with the gap layer along the air bearing surface toward the upper sub-pole. The length of the lower sub-magnetic pole in the vertical direction of the air bearing surface may be set to 1.5 m or more, as in the case of the upper sub-magnetic pole, and is preferably set to 3.0 m or more.

Further, in the thin-film inductive write magnetic head according to the present invention, the boundary surface of the upper magnetic pole layer may be inclined so as to move away from the lower magnetic pole layer as the distance from the upper auxiliary magnetic pole increases. According to this inclination, the magnetic field generated at the edge of the overhanging upper magnetic pole layer is reduced, so that it is possible to avoid problems such as an increase in a recording track width and a magnetization reversal of a recording track adjacent to a recording track where information is recorded. Becomes

The angle of inclination of the boundary surface may be set to 15 ° or more, preferably, 30 ° or more. By setting the inclination angle to 15 ° or more, the magnitude of the magnetic field generated by the overhanging edge of the upper magnetic pole layer can be reliably suppressed to less than half the coercive force Hc of the recording medium. Moreover, if the inclination angle is set to 30 ° or more, even if the overhang length of the upper magnetic pole layer overhanging from the upper sub-pole is large, the magnitude of the magnetic field generated by the edge can be sufficiently increased by two times the coercive force H c. It can be reduced to less than one part. If the overhang length of the upper magnetic pole can be made large in this way, the production yield can be improved.

As described above, in order to obtain an upper magnetic pole layer having an inclined boundary surface, a step of forming an upper sub-magnetic pole on the lower magnetic pole layer at the tip of the thin film induced write magnetic head facing the air bearing surface, A step of laminating an insulating layer thereon and covering the formed upper sub-pole with an insulating layer; a step of subjecting the insulating layer to a flattening process to expose the upper sub-pole; and a step of flattening the upper sub-pole Performing a process of ion milling the surface of the insulating layer containing: a method of manufacturing a thin-film inductive write magnetic head.

According to such a manufacturing method, when the surface of the insulating layer is subjected to ion milling, Since the etching rate differs between the lower sub-pole and the insulating layer, the upper sub-pole is first carved by the ion beam. As a result, a tapered surface is formed at the edge of the insulating layer. If the upper magnetic pole layer is formed using the formed taper surface, an upper magnetic pole layer having an inclined boundary surface can be obtained.

Also, without using such an ion milling process, the photo

■

If a resist is used, an upper pole layer having an inclined interface can be easily obtained. In this case, a photoresist is uniformly applied to the surface of the insulating layer when the surface of the insulating layer has been subjected to the planarization treatment. Then, under exposure and development of the photoresist on the pattern of the upper magnetic pole layer using the mask pattern, under exposure may be used. According to the under exposure, the photoresist is not completely removed, and as a result, a tapered surface is formed in the photoresist near the upper subpole. When the upper magnetic pole layer is formed using this tapered surface, an upper magnetic pole layer having an inclined boundary surface is obtained. Similarly, after the insulating layer is flattened, a resist pattern is formed on the upper auxiliary magnetic pole. An inclined boundary surface may be formed by lift-off. After the resist pattern is formed, if the insulating layer is formed again by sputtering or the like, the insulating layer is not completely laminated at the edge of the resist pattern. As a result, a tapered surface is formed in the insulating layer. If an upper pole layer is formed on such a taper surface, an upper pole layer with a sloping interface can be obtained.

Furthermore, after the planarization of the insulating layer, forming a S ί 0 ₂ insulating film uniformly on the surface of the insulating layer including an upper sub magnetic pole, ZoTsuta Regis Bokuha the upper sub magnetic pole. The turns may be formed on the Sί◦2 insulating film. Here, when heat treatment is performed on the resist pattern, the edge of the resist pattern recedes, and a tapered surface is formed. Subsequently, when a reaction ion etching (RIΕ) process is performed, the SiO ₂ insulating film is also removed while reflecting the shape of the resist pattern. As a result, a tapered surface is formed in the SiO 2 insulating film. If the resist pattern is removed and the upper magnetic pole layer is formed using the formed tapered surface, an upper magnetic pole layer having an inclined boundary surface can be obtained.

The thin-film inductive write magnetic head according to the present invention is combined with a read magnetic head such as a magnetoresistive (MR) element or a giant magnetoresistive (GMR) element. May be used. Further, the magnetic head according to the present invention can be applied to a magnetic disk device such as a hard disk drive (HDD) or a magnetic tape device. BRIEF DESCRIPTION OF THE FIGURES

,,

FIG. 1 is a plan view showing the internal structure of a hard disk drive (HDD). FIG. 2 is a perspective view showing a specific example of a flying head slider.

FIG. 3 is a plan view schematically showing a structure of an inductive write head element provided in the thin-film magnetic head.

FIG. 4 is a partial cross-sectional view taken along line 4-4 in FIG.

FIG. 5 is a diagram showing the state of the air bearing surface viewed from the direction of arrow 5 in FIG.

Fig. 6 is a partially enlarged view of Fig. 5 showing the vicinity of the upper sub-pole and the lower sub-pole. Fig. 7A shows the gap magnetic field and the edge magnetic field distributed along the track width direction of the recording track. 9 is a graph showing a specific example.

FIG. 7B is a graph showing another specific example of the gap magnetic field and the edge magnetic field distributed along the track width direction of the recording track.

FIG. 8 is a partially enlarged view of FIG. 4 showing a state near the upper sub-pole and the lower sub-pole.

FIG. 9 is a graph showing the relationship between the peak value of the edge magnetic field and the vertical length of the air bearing surface.

FIG. 10 is a graph showing the relationship between the maximum head magnetic field, that is, the peak value of the gap magnetic field, and the vertical length of the air bearing surface.

FIG. 11 is a graph showing the relationship between the peak value of the edge magnetic field and the overhang length of the upper pole layer.

FIG. 12 is a view corresponding to FIG. 6 showing the upper pole layer in which the boundary surface is inclined.

FIG. 13 is a graph showing the relationship between the peak value of the edge magnetic field and the inclination angle of the boundary surface.

Figure 14 shows the peak value of the maximum head magnetic field, that is, the gap magnetic field, and the inclination angle of the interface. 6 is a graph showing a relationship with the graph.

FIG. 15 is a graph showing the relationship between the peak value of the edge magnetic field and the overhang length of the upper pole layer.

FIG. 16 is a diagram illustrating a method of forming an upper pole layer having an inclined boundary surface.

FIG. 17 is a diagram showing a method of forming an upper magnetic pole layer having an inclined boundary surface.

■,

FIG. 18 is a diagram illustrating a method of forming an upper magnetic pole layer having an inclined boundary surface.

FIG. 19 is a diagram showing a method of forming an upper magnetic pole layer having an inclined boundary surface.

FIG. 20 is a diagram illustrating a method of forming an upper magnetic pole layer having an inclined boundary surface. BEST MODE FOR CARRYING OUT THE INVENTION

FIG. 1 shows the internal structure of a hard disk drive (HDD) 10 as a specific example of a magnetic disk drive. The housing 11 of the HDD 10 accommodates a magnetic disk 13 mounted on the rotating shaft 12 and a flying head slider 14 facing the magnetic disk 13. The flying head slider 14 is fixed to the tip of a carriage arm 16 that can swing around a swing axis 15. When writing or reading information to or from the magnetic disk 13, the carriage arm 16 is oscillated by an actuator 17 which is composed of a magnetic circuit, and as a result, a flying head slider 14 magnetic disk It is positioned on the desired recording track on 13. The interior space of the housing 11 is closed by a cover (not shown).

FIG. 2 shows a specific example of the flying head slider 14. The flying head slider 14 has a flying surface 19 facing the magnetic disk 13. On the air bearing surface 19, two rails 20 forming an ABS surface (air bearing surface) are formed. The flying head slider 14 can fly above the surface of the magnetic disk 13 by utilizing the air flow 21 received on the floating surface 19 (particularly the ABS surface) while the magnetic disk 13 is rotating. As will be described later, a thin-film magnetic head built-in film 23 in which the thin-film magnetic head 22 is built is formed on the air outflow side end surface of the flying head slider 14. Generally, Tsu Dosuraida 1 4 to levitation is formed from A 1 2 O 3 T i C (AlTiC), head protection film 2 3 thin film magnetic is formed from A 1 ₂ 〇 ₃ (alumina).

The structure of the thin-film magnetic head 22 according to the present invention will be described in detail with reference to FIG. This thin The film magnetic head 22 is provided with an inductive write head element 26 for recording information on the magnetic disk 13 using a magnetic field generated by the spiral-shaped conductor coil pattern 25 c Conductor coil When a magnetic field is generated in the pattern 25, the magnetic field lines are transmitted in the magnetic core 27 penetrating the center of the conductor coil pattern 25.

4, the magnetic core 27 includes an upper magnetic pole layer 8 facing the air bearing surface 19 and a lower magnetic pole layer 29 also facing the air bearing surface 19. The upper magnetic pole layer 28 and the lower magnetic pole layer 29 are connected to each other at the center of the conductor coil pattern 25. On the other hand, at the leading ends of the upper magnetic pole layer 28 and the lower magnetic pole layer 29 facing the air bearing surface 19, the upper magnetic pole layer 28 and the lower magnetic pole layer 29 face each other with the gap layer 30 interposed therebetween. . Lines of magnetic force transmitted through the magnetic core 27 pass between the upper magnetic pole layer 28 and the lower magnetic pole layer 29 at the tips of the upper magnetic pole layer 28 and the lower magnetic pole layer 29 while bypassing the gap layer 30. As a result, the magnetic disk 13 facing the flying surface 19 is magnetized by the magnetic field leaking from the flying surface 19. The upper magnetic pole layer 28 and the lower magnetic pole layer 29 may be made of, for example, NiFe.

In the thin-film magnetic head 22, a magnetoresistive effect (MR) element 31 is used for reading information. MR element 3 1 is sandwiched between and embedded in the AI ₂ 〇 _three layers 3 2 F e N and N i F e of the bottom shield layer 3 3 and the lower magnetic pole layer 2 9. Here, the lower magnetic pole layer 29 functions as an upper shield layer of the MR element 31. As a result, as apparent from FIG. 3, for example, at the tip of the inductive write head element 26 facing the air bearing surface 19, the lower magnetic pole layer 29 is wider than the upper magnetic pole layer 28. . However, instead of the MR element 31, another reading element such as a giant magnetoresistance (GMR) element may be used, and the inductive writing head element 26 is used alone without using the reading element. May be used.

As shown in FIG. 5, at the tip of the inductive write head element 26 facing the air bearing surface 19, an upper sub-pole 35 is formed on the upper pole layer 28, and the upper sub-pole is formed on the lower pole layer 29. A lower secondary magnetic pole 36 opposing 35 is formed. The upper sub pole 35 swells from the interface 37 between the upper pole layer 28 and the gap layer 30 toward the lower pole layer 29. On the other hand, the lower sub pole 36 expands from the interface 38 between the lower pole layer 29 and the gap layer 30 toward the upper pole layer 28. As a result, the upper sub pole 35 and the lower sub pole Between the upper magnetic pole layer 28 and the lower magnetic pole layer 29, a narrow gap layer 39 narrower than the gap layer 30 formed between the upper magnetic pole layer 28 and the lower magnetic pole layer 29 is formed.

The track width of the recording track formed on the medium surface of the magnetic disk 13 is defined by the narrow gap layer 39 thus formed. Therefore, the track width can be reduced as compared with the case where the gap layer 30 formed by the upper magnetic pole layer 28 and the lower magnetic pole layer 29 is simply used. As a result, it is considered that the track density can be increased and the surface recording density on the magnetic disk 13 can be further improved. Since the boundary surface 37 of the upper magnetic pole layer 28 protrudes from the upper sub-magnetic pole 35 along the air bearing surface 19, good overwrite characteristics can be obtained.

Next, the magnetic field characteristics of the inductive write head element 26 described above will be considered. In such an inductive write head element 26, for example, as shown in FIG. 6, the magnetic flux of the upper sub pole 35 is guided toward the medium surface of the magnetic disk 13 by the narrow gap layer 39, It has been found that the magnetic flux of the upper pole layer 28 leaks toward the medium surface of the magnetic disk 13 at the edge 28 a of the upper pole layer 28. In the following description, the former is called a gap magnetic field, and the latter is called an edge magnetic field. Here, when the magnetic field characteristics of the inductive write head element 26 are simulated using three-dimensional magnetic field analysis software, simulation results shown in FIGS. 7A and 7B are obtained, for example. .

As is apparent from FIGS. 7A and 7B, in the inductive write head element 26, the peak value PK of the gap magnetic field AA on the center line of the recording track (the center in the direction of the AA line in FIG. 6). The magnitude of the current flowing through the conductor coil pattern 25 and the widths of the upper sub-pole 35 and the lower sub-pole 36 are determined so that 1 = 600 000 e appears. This is because, in general, magnetic recording of information requires a magnetic field strength twice as large as the medium coercive force H c (−300000) of a recording medium such as the magnetic disk 13. It can be seen that the gap magnetic field A A decreases as it deviates from the center line of the recording track in the horizontal direction of the recording track width.

On the other hand, as is clear from FIGS. 7A and 7B, the edge magnetic field BB is, for example, a peak value PK at a position shifted from the center line of the recording track in the recording track width direction (the direction of the BB line in FIG. 6). It can be seen that 2 ≥ 200 000 e is reached. Generally, medium coercivity It is considered that when a magnetic field is applied with a magnetic field strength of one half of the force Hc, the reversal of magnetization is caused on the recording medium. Therefore, as shown in FIG. 7A, when a sub-peak exceeding the gap magnetic field AA is formed by the edge magnetic field BB having a magnetic field intensity of more than 1500 e, the recording bleeding characteristic is deteriorated by the sub-peak, and a desired recording track is obtained. It is not possible to obtain the work width. Also, as shown in FIG. 7B, even when the edge magnetic field BB does not exceed the gap magnetic field AA, if the edge magnetic field BB exceeds the magnetic field strength of 1500 e, the magnetization recorded on the recording medium with the gap magnetic field AA May be reversed by the edge magnetic field BB. As is clear from Fig. 6, during actual information recording, the edge 28a of the upper pole layer 28 passes through the medium surface after the narrow gap layer 39 passes. .

Now, if the width of the upper magnetic pole layer 28 is reduced at the tip of the inductive write head element 26, the peak value PK 2 of the edge magnetic field BB becomes apparent from the comparison of FIGS. 7A and 7B. It is confirmed that the magnitude of the peak value PK 2 decreases at the same time as moving toward the center line of. That is, the overhang length (see FIG. 6) of the boundary surface 37 of the upper magnetic pole layer 28 protruding from the upper sub pole 35 along the air bearing surface 19 is reduced, and the edge 2 8 of the upper magnetic pole layer 28 is reduced. As a approaches the upper auxiliary pole 35, the peak value PK2 of the edge magnetic field BB decreases. However, the smaller the overhang length, the worse the manufacturing yield.

In the inductive write head element 26 according to the present embodiment, the vertical length GD of the air bearing surface of the upper sub-pole 35 and the lower sub-pole 36 is set to 1.5 or more, preferably 3.0 or more. Is done. Here, the vertical length GD of the air bearing surface is defined by the lengths of the upper sub magnetic pole 35 and the lower sub magnetic pole 36 extending inward in the vertical direction from the air bearing surface 19, as shown in FIG. As a result of simulating the magnetic field characteristics using the same three-dimensional magnetic field analysis software as described above, for example, the simulation results shown in FIG. 9 were obtained. However, the overhang length A PW was set to 0.2 m. At present, it is difficult to set the overhang length △ PW to less than 0.2 ^ m in view of the dimensional tolerances during manufacturing.

As is evident from Fig. 9, when the vertical length GD of the air bearing surface is set to 1.5 ^ m or more, the peak value PK 2 of the edge magnetic field falls below 1 500 e, which is the lower limit of magnetization reversal. Times As a result, it is understood that there is no possibility that the magnetic field recorded on the recording medium by the gap magnetic field AA is inverted by the edge magnetic field BB. As can be seen from Fig. 10, it can be seen that changing the vertical length GD of the air bearing surface in this way has almost no effect on the maximum head magnetic field, that is, the peak value PK1 = 60000 e of the gap magnetic field AA. You.

Moreover, as shown in Fig. 11, increasing the vertical length GD of the air bearing surface can sufficiently suppress the peak value PK 2 of the edge magnetic field BB to 15,000 e or less even if the overhang length ΔΡ ν is large. be able to. Therefore, the floating surface vertical length D

It is desirable that G be set to 3.0 m or more, and that the overhang length ΔΡ \ ν of the boundary surface 37 be set to 0.4 m or less. Air bearing surface vertical length G

By setting D to 3, it is possible to secure a sufficiently large overhang length APW and improve the production yield.

Instead of adjusting the vertical length GD of the air bearing surface as described above, a slope may be provided at the boundary surface 37 of the upper pole layer 28, for example, as shown in FIG. According to this inclination, the boundary surface 37 is separated from the lower magnetic pole layer 29 as the distance from the upper sub magnetic pole 35 increases. In the inductive write head element 26 according to the present embodiment, the inclination angle S of the boundary surface 37 is set to 15 ° or more, preferably 30 ° or more. Here, the inclination angle 0 is defined by the angle of the boundary surface 37 with respect to one surface parallel to the lower magnetic pole layer 29 when viewed from the air bearing surface 19 side. Under the same conditions as above, the magnetic field characteristics were simulated using three-dimensional magnetic field analysis software. For example, the simulation results shown in Fig. 13 were obtained. However, the vertical length GD of the air bearing surface was set to 1.5 m, and the overhang length was set to 0.3.

As is clear from FIG. 13, when the inclination angle 0 is set to 15 ° or more, the peak value PK 2 of the edge magnetic field is smaller than 15000 e, which is the lower limit of the magnetization reversal. As shown in Fig. 14, even if the tilt angle 0 is changed in this way, it is almost impossible to affect the maximum head magnetic field, that is, the peak value PK 1 = 60000 e of the gap magnetic field AA. .

Moreover, as shown in Fig. 15, when the inclination angle S is increased, the peak value PK 2 of the edge magnetic field BB can be sufficiently reduced to 15000 e or less even if the overhang length PW is large. Can be held down. Therefore, the inclination angle S of the boundary surface 37 is 30. At the same time, it is desirable that the overhang length ΔΡ \ Υ of the boundary surface 37 be set to 0.45 m or less. If the inclination angle 0 of the boundary surface 37 is set to 30 ° or more, it is possible to secure a sufficiently large overhang length ΔPW and improve the yield during manufacturing. In Figure 15, the vertical length GD of the air bearing surface is 1.

:

Set to 5 m.

Here, a method of forming the upper magnetic pole layer 28 having the boundary surface 37 with the inclination angle S will be described in detail. First, as shown in FIG. 16A, a lower magnetic pole layer 29 and a gap layer 30 are laminated on an AlTiC substrate according to a known method. Subsequently, as shown in FIG. 16 (b), the upper sub-pole 35 is formed on the gap layer 30 by plating film formation or the like. Using the formed upper sub-pole 35 as a mask, an ion mill is performed as shown in FIG. 16 (c). With this ion mill, gap layer 30 and lower pole layer

The lower sub-pole 36 facing the upper sub-pole 35 with the narrow gap layer 39 interposed therebetween is formed.

Subsequently, as shown in FIG. 17A, an insulating layer 41 such as alumina is coated on the lower magnetic pole layer 29. As a result, the upper sub pole 35 is covered by the coated insulating layer 41. Thereafter, as shown in FIG. 17 (b), the insulating layer 41 is subjected to flattening polishing to expose the upper sub pole 35. Here, as shown in Fig. 17 (c), the upper auxiliary pole

The surface of the insulating layer 41 containing 35 is subjected to ion milling. Then, since the etching rate differs between the alumina of the insulating layer 41 and the material of the upper sub-pole 35, the upper sub-pole 35 is carved first. As a result, a tapered surface 42 is formed at the edge of the insulating layer 41. As shown in FIG. 17D, when the upper magnetic pole layer 28 is formed so as to overlap the formed taper surface 42, the upper magnetic pole layer 28 in which the boundary surface 37 is inclined can be obtained. In forming the upper magnetic pole layer 28, for example, a plating film using the photo resist 43 may be adopted.

Even without using such an ion mill treatment, the upper magnetic pole layer 28 inclined at the interface 37 can be easily obtained by using the photoresist at the time of forming the upper magnetic pole layer 28. In this case, when the surface of the insulating layer 41 is subjected to the planarization polishing as shown in FIG. 17 (b), for example, the photoresist 45 is uniformly applied as shown in FIG. 18 (a). Apply to. Thereafter, a photoresist 45 is exposed and developed on the pattern of the upper magnetic pole layer 28 using a mask pattern (not shown). At this time, when the under exposure is used, the photoresist 45 is not completely removed in the pattern of the upper magnetic pole layer 28 as shown in FIG. 18B, and as a result, the photoresist near the upper sub magnetic pole 35 is not removed. A taper surface 46 is formed at the bottom 45. When the upper magnetic pole layer 28 is formed using the taper surface 46, the upper magnetic pole layer 28 in which the boundary surface 37 is inclined is obtained.

Similarly, after the flattening and polishing of the insulating layer 41, for example, as shown in FIG. 19A, a resist pattern 48 is formed on the upper sub-pole 35, and a boundary surface 37 inclined by lift-off is formed. May be. After the resist pattern 48 is formed, if the insulating layer 49 is formed again by sputtering or the like as shown in FIG. 19 (a), the insulating layer 49 is not completely laminated in the vicinity of the resist pattern 48. As a result, a tapered surface 50 is formed on the insulating layer 49. After removing the resist pattern 48, as shown in FIG. 19 (b), if the upper magnetic pole layer 28 is formed so as to overlap the tapered surface 50, the upper magnetic pole layer 28 in which the boundary surface 37 is inclined can be obtained.

Furthermore, after flattening and polishing the insulating layer 41, for example, as shown in FIG. 20 (a), a SiO ₂ insulating film 52 is uniformly formed on the surface of the insulating layer 41 including the upper sub-pole 35, A resist pattern 53 imitating the upper sub-pole 35 may be formed on the SiO ₂ insulating film 52. Here, when the resist pattern 53 is subjected to a heat treatment, the edge of the resist pattern 53 recedes, and a tapered surface 54 is formed. Subsequently, as shown in FIG. 20B, when the RIE (reactive ion etching) process is performed, the SiO ₂ insulating film 52 is also removed while reflecting the shape of the resist pattern 53. As a result, a tapered surface 55 is formed on the SiO ₂ insulating film 52. The resist pattern 53 is removed as shown in FIG. 20 (c), and the upper magnetic pole layer 28 is formed on the formed taper surface 55 as shown in FIG. 20 (d). The inclined upper pole layer 28 can be obtained.

Claims

The scope of the claims

1. Upper magnetic pole layer facing the air bearing surface, lower magnetic pole layer facing the upper magnetic pole layer with the gap layer interposed, and facing the floating surface, and formed on the upper magnetic pole layer, from the boundary surface with the gap layer to the air bearing surface An upper sub-pole swelling toward the lower magnetic pole layer along with the upper sub-pole, and the vertical length of the air bearing surface of the upper sub-pole is set to 1.5 m or more.

2. The thin-film inductive write head according to claim 1, wherein a vertical length of the air bearing surface of the upper sub-pole is set to 3.0 m or more. Magnetic head.

3. The thin-film inductive write magnetic head according to claim 1, wherein the boundary surface of the upper pole layer has an overhang length of 0.4 im or less along the air bearing surface. A thin-film inductive writing magnetic head that protrudes from the magnetic pole.

4. The thin-film inductive write magnetic head according to claim 1, wherein the boundary surface of the upper magnetic pole layer is inclined away from the lower magnetic pole layer as the distance from the upper auxiliary magnetic pole increases. Characterized thin-film inductive write magnetic head.

5. The thin-film inductive writing magnetic head according to claim 4, wherein the inclination angle of the boundary surface is set to 15 ° or more.

6. The thin-film inductive writing magnetic head according to claim 5, wherein an inclination angle of the boundary surface is set to 30 ° or more.

7. The thin-film inductive write magnetic head according to claim 1, wherein the lower pole is A lower sub-pole that is formed on the layer and swells from the boundary surface with the gap layer along the air-bearing surface toward the upper sub-magnetic pole, and the vertical length of the lower sub-magnetic pole in the air-bearing surface is 1.5 m or more. A thin-film inductive write magnetic head characterized by being set.

8. The thin-film inductive write magnetic head according to claim 7, wherein said lower portion,

The thin-film inductive writing magnetic head characterized in that the vertical length of the sub-pole is set at least 3.0 m in the air bearing surface.

9. The thin-film inductive write magnetic head according to claim 7, wherein the boundary surface of the upper pole layer has an overhang length of 0.4 m or less along the air bearing surface. A thin-film inductive writing magnetic head that protrudes from the magnetic pole.

10. The thin-film inductive write magnetic head according to claim 7, wherein the boundary surface of the upper magnetic pole layer is inclined so as to move away from the lower magnetic pole layer as the distance from the upper auxiliary magnetic pole increases. A thin-film inductive write magnetic head.

11. The thin-film inductive writing magnetic head according to claim 10, wherein an inclination angle of the boundary surface is set to 15 ° or more. '.

12. The thin-film inductive writing magnetic head according to claim 11, wherein the inclination angle of the boundary surface is set to 30 ° or more. '.

1 3. A step of forming an upper sub-pole on the lower pole layer at the tip of the thin-film inductive write magnetic head facing the air bearing surface, and an upper sub-pole formed by laminating an insulating layer on the lower pole layer Covering the insulating layer with an insulating layer, performing a planarizing process on the insulating layer to expose the upper sub-magnetic pole, and performing an ion milling process on the surface of the insulating layer including the planarized upper sub-magnetic pole. A method for producing a thin-film inductive write magnetic head, comprising:

1 4. A step of forming an upper sub-pole on the lower pole layer at the tip of the thin-film inductive write magnetic head facing the air bearing surface, and an upper sub-pole formed by laminating an insulating layer on the lower pole layer Covering the insulating layer with an insulating layer, performing a planarizing process on the insulating layer to expose the upper sub-pole, and applying a photoresist on the surface of the insulating layer including the planarized upper sub-pole. And a step of removing the photoresist by underexposure.

15. Step of forming an upper sub-pole on the lower pole layer at the tip of the thin-film inductive write magnetic head facing the air bearing surface, and laminating an insulating layer on the lower pole layer to form the upper sub-pole Covering the insulating layer with an insulating layer, performing a planarizing process on the insulating layer to expose the upper sub-pole, forming a resist pattern on the exposed upper sub-pole, and a surface of the insulating layer including the resist pattern. Forming a thin-film inductive write magnetic head.

16. Step of forming an upper sub-pole on the lower pole layer at the tip of the thin-film inductive writing magnetic head facing the air bearing surface, and laminating an insulating layer on the lower pole layer to form the upper sub-pole Covering the insulating layer with an insulating layer, flattening the insulating layer to expose the upper sub-pole, and forming an insulating film uniformly on the surface of the insulating layer including the flattened upper sub-pole. Film forming, forming a resist pattern imitating the upper sub-magnetic pole on the insulating film, heat-treating the resist pattern, and forming a resist pattern including the heat-treated resist pattern. Subjecting the surface to a reactive ion etching treatment.