Method of manufacturing a thin-film magnetic head

A thin-film magnetic head is constructed such that a main magnetic pole layer, a lower shield layer, an upper shield layer and a thin-film coil are laminated on a substrate. A method of manufacturing the thin-film magnetic head has a lower shield layer forming step. This step comprises a step of forming a first lower shield part in a lower shield planned area, including a planned line along the medium-opposing surface, a step of forming a partial lower seed layer having a partial arrangement structure in which the partial lower seed layer is arranged on a lower formation zone except a lower exception zone including the planned line, a step of forming a second lower shield part on the partial lower seed layer.

BACKGROUND

1. Field of the Invention

The present invention relates to a method of manufacturing the thin-film magnetic head which performs a magnetic recording action by a perpendicular magnetic recording scheme, the thin-film magnetic head, a head gimbal assembly, and a hard disk drive.

2. Related Background Art

A hard disk drive has a large recording capacity and is used as the heart of a storage device. The hard disk drive records and reproduces data to/from a hard disk (recording medium) by a thin-film magnetic head.

The thin-film magnetic heads can roughly be classified according to their recording schemes into those of longitudinal magnetic recording type and those of perpendicular magnetic recording type. The longitudinal magnetic recording scheme records data in a (longitudinal) direction within a recording surface of a hard disk (recording medium), while the perpendicular magnetic recording scheme records data such that the direction of recording magnetization formed in the hard disk is made perpendicular to the recording surface. The thin-film magnetic heads of perpendicular magnetic recording type have been considered more promising than those of longitudinal magnetic recording type, since they can realize a much higher recording density than that in the longitudinal magnetic recording scheme, while their recorded hard disks are less susceptible to heat fluctuation.

Meanwhile, a conventional magnetic head of perpendicular magnetic recording type (perpendicular magnetic recording head which will also be referred to as “PMR” in the following) has a magnetic pole layer and a thin-film coil. The PMR has a structure of electromagnet which the thin-film coil are wound around the magnetic pole layer.

For example, a conventional PMR has a main magnetic pole layer having a magnetic pole end face on a side of a medium-opposing surface opposing a recording medium, a thin-film coil which generates a magnetic field passes through the inside of the main magnetic pole layer, and a return magnetic pole layer linked to the main magnetic pole layer through a linking part.

Meanwhile, a PMR that a shield layer is formed near the main magnetic pole layer is known. For example, in JP 2010-157303 (referred to also as Patent Document 1), the PMR that the shield layer is formed on a leading side of the main magnetic pole layer is disclosed. In this PMR, an end face of the shield layer is disposed in the medium-opposing surface together with a magnetic pole end part of the main magnetic pole layer. Besides, in JP 2008-97826 (referred to also as Patent Document 2), the PMR that the shield layer is formed on a trailing side of the main magnetic pole layer is disclosed. In this PMR, the end face of the shield layer is disposed in the medium-opposing surface together with a magnetic pole end part of the main magnetic pole layer, too.

SUMMARY OF THE INVENTION

In the above-described conventional PMR, a shield layer formed near the main magnetic pole layer can prevent a magnetic flux emitted from the magnetic pole end face from reaching an area different from the recording target area on the recording medium. Therefore, in the above-described conventional PMR, failure such as recording of error data on the area different from the recording target area or erasure of recorded data can be reduced.

However, in the above-described conventional PMR, the shield layer has a structure in which a plurality of shield parts are stacked (such a shield layer is referred also to as a multiple shield layer) and the shield layer is formed near the main magnetic pole layer in the medium-opposing surface, and therefore the following problems are not solved yet.

Specifically, when forming the multiple shield layer, for example, a first shield part is formed by plating method, and then a second shield part is formed by plating method to overlie the first shield part. Further, when forming the second shield part, a seed layer being a ground of the second shield part is formed on the first shield part and a plating film is grown on the seed layer to form the second shield part.

When forming the first shield part and the second shield part, electro plating is mainly employed. In this case, the substrate is immersed in a plating solution and electric current is passed through the plating solution to cause a plating film made of a magnetic material to grow on the substrate, and the plating film is used to form the first shield part and the second shield part.

In contrast to the above, the seed layer is formed by sputtering or the like under a dry environment without using solution. Therefore, the first shield part and the second shield part are formed using the same magnetic material as but different in the direction of crystal from the seed layer.

Generally, the magnetic characteristics of the magnetic material are different according to the direction of crystal, and the direction through which the magnetic flux easily transmits is different depending on the direction of crystal. Therefore, if a seed layer different in magnetic characteristics from the first shield part and the second shield part exists between them in the medium-opposing surface, components of the magnetic flux emitted from the magnetic pole end face become difficult to be absorbed.

More specifically, after the magnetic flux according to the recording magnetic field is emitted from the magnetic pole end face, components of the magnetic flux spreading in the track width direction and the like are not absorbed by the first shield part or the second shield part but likely to remain. Then, the remaining magnetic flux tends to cause a phenomenon that data recorded on a track adjacent to a track on which data is to be recorded or a track located at a position distanced by about several μm to several tens μm from the track on which data is to be recorded is erased (these phenomena are referred also to as adjacent track erasure (ATE) and wide area track erasure (WATE)).

The present invention is made to solve the above problem, and it is an object to improve ATE and WATE caused by a multiple shield layer in a method of manufacturing a thin-film magnetic head which performs a magnetic recording action by a perpendicular magnetic recording scheme, the thin-film magnetic head, a head gimbal assembly, and a hard disk drive.

To solve the above problem, the present invention is a method of manufacturing a thin-film magnetic head constructed such that a main magnetic pole layer having a magnetic pole end face on a side of a medium-opposing surface opposing a recording medium, a lower shield layer and an upper shield layer having respective shield end faces arranged in the medium-opposing surface and arranged to hold the main magnetic pole layer therebetween, and a thin-film coil wound around any one of the main magnetic pole layer, the lower shield layer, and the upper shield layer are laminated on a substrate, a lower shield layer forming step of forming the lower shield layer including the following steps (1) to (3):

(1) a first lower shield part forming step of forming a first lower shield part constituting the lower shield layer in a lower shield planned area on the substrate, including a planned line along the medium-opposing surface which the medium-opposing surface is formed later;

(2) a lower seed layer forming step of forming a partial lower seed layer having a partial arrangement structure in which the partial lower seed layer is arranged on a lower formation zone except a lower exception zone including the planned line when forming a lower seed layer for forming a second lower shield part constituting the lower shield layer on the first lower shield part; and

(3) a second lower shield part forming step of forming the second lower shield part on the partial lower seed layer.

According to the above-described manufacturing method, the partial lower seed layer being the ground when forming the second lower shield part has the partial arrangement structure, so that the partial lower seed layer is not arranged on the planned line. Therefore, by forming the medium-opposing surface along the planned line, the partial lower seed layer can be made not to appear in the medium-opposing surface.

In the above-described method of manufacturing the thin-film magnetic head, it is preferable that an upper shield layer forming step of forming the upper shield layer includes the following steps (4) to (5), in the first upper shield part forming step, the first upper shield part is formed on the partial upper seed layer.

(4) an upper seed layer forming step of forming a partial upper seed layer having a partial arrangement structure in which the partial upper seed layer is arranged on an upper formation zone except an upper exception zone including the planned line when forming an upper seed layer for forming a first upper shield part constituting the upper shield layer on the main magnetic pole layer

(5) a first upper shield part forming step of forming the first upper shield part.

According to the above-described manufacturing method, the partial upper seed layer being the ground when forming the first upper shield part has the partial arrangement structure, so that the partial upper seed layer is also not arranged on the planned line. Therefore, the partial upper seed layer can be made not to appear in the medium-opposing surface.

In the above-described method of manufacturing the thin-film magnetic head, it is preferable that the lower seed layer forming step includes the following steps (6) to (7).

(6) a wide lower seed layer forming step of forming a wide lower seed layer arranged on the lower exception zone and the lower formation zone on an upper face of a multilayer body including the substrate when forming the partial lower seed layer

(7) a lower seed layer removing step of removing an excepted lower seed layer formed on the lower exception zone of the wide lower seed layer.

According to the above-described manufacturing method, the wide lower seed layer is formed on the upper face of the multilayer body and then the excepted lower seed layer is removed, whereby the partial lower seed layer is formed.

Further, in the above-described method of manufacturing the thin-film magnetic head, it is preferable that the upper seed layer forming step includes the following steps (8) to (9).

(8) a wide upper seed layer forming step of forming a wide upper seed layer arranged on the upper exception zone and the upper formation zone on an upper face of a multilayer body including the substrate when forming the partial upper seed layer.

(9) an upper seed layer removing step of removing an excepted upper seed layer, of the wide upper seed layer, formed on the upper exception zone.

According to the above-described manufacturing method, the wide upper seed layer is formed on the upper face of the multilayer body and then the excepted upper seed layer is removed, whereby the partial upper seed layer is formed.

Further, in the above-described method of manufacturing the thin-film magnetic head, it is preferable that in the lower seed layer forming step, the lower exception zone is set in a band-shaped area along the medium-opposing surface including the whole planned line.

According to this manufacturing method, since the partial lower seed layer is not arranged on any part on the planned line, the partial lower seed layer can be made not to appear at all in the medium-opposing surface.

Further, in the above-described method of manufacturing the thin-film magnetic head, it is preferable that in the upper seed layer forming step, the upper exception zone is set in a band-shaped area along the medium-opposing surface including the whole planned line.

According to this manufacturing method, since the partial upper seed layer is not arranged on any part on the planned line, the partial upper seed layer can be made not to appear at all in the medium-opposing surface.

Further, in the above-described method of manufacturing the thin-film magnetic head, it is preferable that assuming that a direction separating from the medium-opposing surface toward a position where the thin-film coil is formed on the substrate is a depth direction, the lower exception zone is secured along the depth direction from outside the planned line, in the lower seed layer forming step.

Further, in the above-described method of manufacturing the thin-film magnetic head, it is preferable that assuming that a direction separating from the medium-opposing surface toward a position where the thin-film coil is formed on the substrate is a depth direction, the upper exception zone is secured along the depth direction from outside the planned line, in the upper seed layer forming step.

Further, in the above-described method of manufacturing the thin-film magnetic head, it is preferable that an upper shield layer forming step of forming the upper shield layer, includes the following steps (10) to (13).

(10) a first upper shield part forming step of forming a first upper shield part constituting the upper shield layer

(11) a second upper shield part forming step of forming a second upper shield part constituting the upper shield layer on the medium-opposing surface side of a conductor layer constituting the thin-film coil such that the second upper shield part is connected to the first upper shield part and arranged in the medium-opposing surface

(12) a linking shield part forming step of forming a linking shield part constituting the upper shield layer such that the linking shield part is connected to the second upper shield part, straddles the thin-film coil, and recesses from the medium-opposing surface to be distanced from the medium-opposing surface

(13) a trimming step of cutting off a part of the second upper shield part on the medium-opposing surface side that is not covered with the linking shield part.

In case of the above-described method of manufacturing, it is preferable that in the trimming step, the part of the second upper shield part, on the medium-opposing surface side, which is not covered with the linking shield part is cut off using the linking shield part formed by the linking shield part forming step as a mask.

Further, the present invention provides a thin-film magnetic head constructed such that a main magnetic pole layer having a magnetic pole end face on a side of a medium-opposing surface opposing a recording medium, a lower shield layer and an upper shield layer having respective shield end faces arranged in the medium-opposing surface and arranged to hold the main magnetic pole layer therebetween, and a thin-film coil wound around any one of the main magnetic pole layer, the lower shield layer, and the upper shield layer are laminated on a substrate, the thin-film magnetic head including: a first lower shield part constituting the lower shield layer, a second lower shield part constituting the lower shield layer and formed on the first lower shield part; and a lower seed layer for forming the second lower shield part by plating, the lower seed layer is formed as a partial lower seed layer having a partial arrangement structure in which the partial lower seed layer is arranged only on a lower formation zone which is receding from the medium-opposing surface.

In case of the above-described a thin-film magnetic head, it is preferable that the thin-film magnetic head further includes a first upper shield part constituting the upper shield layer and formed on the main magnetic pole layer; an upper seed layer arranged between the main magnetic pole layer and the first upper shield part, for forming the first upper shield part by plating, the upper seed layer is formed as a partial upper seed layer having a partial arrangement structure in which the partial upper seed layer is arranged only on an upper formation zone which is receding from the medium-opposing surface.

Further, in case of the above-described a thin-film magnetic head, it is preferable that a lower absence zone where the lower seed layer does not exist is formed between the first lower shield part and the second lower shield part, and an end face of the partial lower seed layer appears in the lower absence zone without appearing in the medium-opposing surface.

It is possible that an upper absence zone where the upper seed layer does not exist is formed between the main magnetic pole layer and the first upper shield part, and an end face of the partial upper seed layer appears in the upper absence zone without appearing in the medium-opposing surface.

Further, in case of the above-described a thin-film magnetic head, it is preferable that the lower absence zone is set in a band-shaped area over an entire width direction of the medium-opposing surface along the medium-opposing surface between the medium-opposing surface and the lower formation zone.

It is possible that the upper absence zone is set in a band-shaped area over an entire width direction of the medium-opposing surface along the medium-opposing surface between the medium-opposing surface and the upper formation zone

Further, the present invention provides a head gimbal assembly including a thin-film magnetic head formed on a support and a gimbal for securing the support; the thin-film magnetic head is constructed such that a main magnetic pole layer having a magnetic pole end face on a side of a medium-opposing surface opposing a recording medium, a lower shield layer and an upper shield layer having respective shield end faces arranged in the medium-opposing surface and arranged to hold the main magnetic pole layer therebetween, and a thin-film coil wound around any one of the main magnetic pole layer, the lower shield layer, and the upper shield layer are laminated on a substrate, the thin-film magnetic head including: a first lower shield part constituting the lower shield layer; a second lower shield part constituting the lower shield layer and formed on the first lower shield part; and a lower seed layer for forming the second lower shield part by plating, the lower seed layer is formed as a partial lower seed layer having a partial arrangement structure in which the partial lower seed layer is arranged only on a lower formation zone which is receding from the medium-opposing surface.

Further, the present invention provides a hard disk drive including a head gimbal assembly having a thin-film magnetic head and a recording medium opposing the thin-film magnetic head; the thin-film magnetic head is constructed such that a main magnetic pole layer having a magnetic pole end face on a side of a medium-opposing surface opposing a recording medium, a lower shield layer and an upper shield layer having respective shield end faces arranged in the medium-opposing surface and arranged to hold the main magnetic pole layer therebetween, and a thin-film coil wound around any one of the main magnetic pole layer, the lower shield layer, and the upper shield layer are laminated on a substrate, the thin-film magnetic head including: a first lower shield part constituting the lower shield layer; a second lower shield part constituting the lower shield layer and formed on the first lower shield part; and a lower seed layer for forming the second lower shield part by plating, the lower seed layer is formed as a partial lower seed layer having a partial arrangement structure in which the partial lower seed layer is arranged only on a lower formation zone which is receding from the medium-opposing surface.

The present invention will be more fully understood from the detailed description given hereinbelow and the accompanying drawings which are given by way of illustration only, and thus are not to be considered as limiting the present invention.

DETAILED DESCRIPTION OF THE EMBODIMENTS

In the following, embodiments of the present invention will be described with reference to the drawings. Note that the same components will be referred to with the same numerals or letters, while omitting their overlapping descriptions.

First Embodiment

To begin with, the structure of a thin-film magnetic head of perpendicular magnetic recording type according to the first embodiment of the present invention will be explained with reference toFIG. 1toFIG. 9. Here,FIG. 1is a sectional view of the thin-film magnetic head300according to a first embodiment of the present invention taken along the line1-1ofFIG. 2, along by a direction intersecting its air bearing surface (which will hereinafter be referred to as “ABS”),FIG. 2is a front view illustrating the ABS30of the thin-film magnetic head300.FIG. 3is a plan view illustrating a lower thin-film coil11.FIG. 4is a plan view illustrating an upper thin-film coil51.FIG. 5is a plan view illustrating a principal part of the lower thin-film coil11.FIG. 6is a perspective view illustrating principal parts of an opposing shield part61, an upper front shield part62and a linking shield part63.FIG. 7is a side elevation view illustrating a pre-trim shield part62A and the upper front shield part62.FIG. 8illustrates a modified example, in which (a) is a side elevation view of the upper front shield part62not having a lateral flat part, in which (b) is a side elevation view of the upper front shield part62not having a longitudinal flat part.FIG. 9is a sectional view illustrating a principal part ofFIG. 1.

The thin-film magnetic head300comprises a substrate1and reproducing and recording heads laminated on the substrate1, while having the ABS30as a medium-opposing surface opposing a recording medium. The following will explain structures of main parts of the thin-film magnetic head300, while structures of parts other than the main parts will later be explained in manufacturing steps.

The reproducing head has an MR device5, arranged near the ABS30, for detecting a magnetic signal. The reproducing head has an insulating layer2formed on the substrate1, a lower shield layer3made of a magnetic material, and a shield gap film4shielding the MR device5.

The reproducing head further has an upper shield layer6made of a magnetic material formed on the shield gap film4, and an insulating layer7formed on the upper shield layer6. The reproducing head is arranged in a position closer to the substrate1than the recording head.

The MR device5is constituted by a magnetosensitive film exhibiting a magnetoresistive effect, such as AMR (anisotropic magnetoresistive), GMR (giant magnetoresistive), and TMR (tunneling magnetoresistive) devices.

The upper shield layer6has an insulating part6bin the middle thereof. Further, a first shield part6ais formed on the lower side of the insulating part6band a second shield part6cis formed on the upper side of the insulating part6b.

In the thin-film magnetic head300, a heating part8is formed in the insulating layer2. The heating part8is also called a DFH (Disk flying heater) and has a function of generating heat by electric current flowing therethrough and conducting the heat to the upper shield layer6and the like. Further, a heat sensing part9is formed in the insulating layer7. The heat sensing part9is also called an HDI (Head Disk Interlayer) sensor. The heat sensing part9is formed using an element which senses heat (temperature) near the upper shield layer6and changes in resistance value according to the sensed heat.

Further, in the thin-film magnetic head300, the heating part8heats the upper shield layer6and the lower shield layer3. The upper shield layer6and the lower shield layer3expand in volume by the heat received from the heating part8. As a result, assuming that the upper shield layer6and the lower shield layer3come into contact with a recording medium not illustrated inFIG. 1, parts of the upper shield layer6and the lower shield layer3near the ABS30become heated due to friction. In the thin-film magnetic head300, a judgment whether or not the upper shield layer6and the lower shield layer3have come into contact with the recording medium is made by detecting the change in resistance value of the heat sensing part9caused by the friction heat. Further, the frying height is controlled while controlling the current value flowing through the heating part8according to the judgment result.

The recording head has a lower thin-film coil11, a main magnetic pole layer26, a gap layer29, a lower shield layer40, an upper thin-film coil51, an write shield layer60, an upper yoke layer65, a displacement suppression layer85and protective insulating layer90, which are laminated on the substrate1.

In the thin-film magnetic head300, the lower thin-film coil11and the upper thin-film coil51form a continuous thin-film coil. The lower thin-film coil11corresponds to a part of the continuous thin-film coil, disposed between the main magnetic pole layer26and the substrate1.

As illustrated inFIG. 3, the lower thin-film coil11has three turn parts11b,11d,11f. The turn parts11b,11d,11fare arranged between a later-described connecting shield part41and a first rear shield part44. The lower thin-film coil11has a structure which the turn parts11b,11d,11falign with each other while interposing a photoresist layer15therebetween. Since the turn part11bis arranged at a closest position to the ABS30of the turn parts11b,11d,11f, the turn part11bcorresponds to a front turn part. The turn part11fcorresponds to a rear turn part.

The lower thin-film coil11has a loop part11aextending from a lead part13A to the turn part11b, a one-loop part11cextending from the turn part11bto the turn part11d, and a one-loop part11eextending from the turn part11dto a turn part11f, and a half-loop part11gextending from the turn part11fto a connecting part11h.

The lower thin-film coil11is constructed as a continuous line from the lead part13A to the connecting part11, so as to be wound as a flat spiral about the lower shield layer40, thus forming a three-turn loop as a whole. For convenience of illustration,FIG. 1illustrates only the turn parts11b,11d,11fand connecting part11hin the lower thin-film coil11. Each of the turn parts11b,11d,11fhas a longitudinally long structure in which the thickness (height in a direction (upper and lower direction) along with the ABS30) greater than the lateral width. Note that the lateral width means width in a direction (intersecting direction) intersecting the ABS30, in this embodiment.

In the lower thin-film coil11, as illustrated inFIG. 5, the one-loop part11chas a variable width structure in which the width gradually decreases toward the ABS30and becomes the smallest at the position closest to the ABS30. Namely, when widths Wd1, Wd2, Wd0are defined in the one-loop part11cas illustrated inFIG. 5, Wd1>Wd2>Wd0. The narrowest part in the one-loop part11cis the turn part11d. The loop part11aand the one-loop part11ehave a variable width structure similar to that of the one-loop part11c, while the narrowest part is the turn part11b,11f. Here, the respective widths of the turn parts11b,11d,11fare Wb0(about 0.9 μm), Wd0(about 0.9 μm) and Wf0(about 0.9 μm).

The lower thin-film coil11forms a following continuous 3-turn loop. Namely, the lead part13A is connected to the connecting part11hthrough the loop part11a, the one-loop part11c, one-loop part11eand the half-loop part11g, whereby the 3-turn loop is formed.

Note that the distance from a front side face11bfof the turn part11bto the ABS30means a front distance of the lower thin-film coil11. Besides, the distance from a rear side face11frof the turn part11fto the ABS30means a rear distance of the lower thin-film coil11.

Next, the upper thin-film coil51will be explained. As illustrated inFIG. 4, the upper thin-film coil51has three turn parts51g,51e,51c. The turn parts51g,51e,51care arranged between a later-described upper front shield part62and a rear shield part64. The upper thin-film coil51has a structure which the turn parts51g,51e,51calign with each other while interposing a photoresist layer55therebetween. Since the turn part51gis arranged at a closest position to the ABS30of the turn parts51g,51e,51c, the turn part51gcorresponds to a front turn part. The turn part51ccorresponds to a rear turn part.

The upper thin-film coil51has a loop part51bextending from a connecting part51ato the turn part51c, a one-loop part51dextending from the turn part51cto the turn part51e, and a one-loop part51fextending from the turn part51eto a turn part51g, and a half-loop part51hextending from the turn part51gto a lead part14A.

The upper thin-film coil51is constructed as a continuous line from the connecting part51ato the lead part14A, so as to be wound as a flat spiral about the write shield layer60, thus forming a three-turn loop as a whole. For convenience of illustration,FIG. 1illustrates only the turn parts51g,51e,51cand the connecting part51ain the upper thin-film coil51. Each of the turn parts51g,51e,51chas the longitudinally long structure and the variable width structure similarly to the turn parts11b,11d,11f. The narrowest part in the one-loop part51f, one-loop part51dand the loop part51bare the turn part51g,51e,51crespectively.

The upper thin-film coil51forms a following continuous 3-turn loop. Namely, the connecting part51ais connected to the lead part14A through the loop part51b, the one-loop part51d, one-loop part51fand the half-loop part51h, whereby the 3-turn loop is formed.

Further, as illustrated inFIG. 1, the upper thin-film coil51has an upper end face51A. The upper end face51A is disposed at a position most distanced from the substrate1. The upper end face51A is formed without level difference to a later-described shield upper end face62fto form a common flat surface59(seeFIG. 35) together with the shield upper end face62f. Further, the upper thin-film coil51is connected to an upper face of a later-described upper yoke layer65via only the interlayer insulating layer32. The upper thin-film coil51is connected to the upper yoke layer65without a magnetic layer made of a magnetic material intervening therebetween.

In the thin-film magnetic head300, the connecting part11hof the lower thin-film coil11is connected to the connecting part51aof the upper thin-film coil51. By this, the lower thin-film coil11and the upper thin-film coil51form a series of coils. A current corresponding to data to be recorded on a recording medium is flowed through the lower thin-film coil11and the upper thin-film coil51, a recording magnetic field is generated by the current.

Next, the main magnetic pole layer26will be explained. The main magnetic pole layer26is formed using a magnetic material made of a ferromagnetic body such as NiFe, CoNiFe, CoFe or the like. The ferromagnetic body such as NiFe, CoNiFe, CoFe or the like has a high magnetic permeability. Therefore, a magnetic flux is likely to transmit through the main magnetic pole layer26, much more magnetic flux transmit through the main magnetic pole layer26. For this reason, more strong magnetic flux corresponding to the recording magnetic field is emitted from the main magnetic pole layer26to the ABS30.

The main magnetic pole layer26has a magnetic pole end face26aon the ABS30side, as illustrated inFIG. 2,FIG. 9. The magnetic pole end face26ahas a bevel form which is wider on the upper thin-film coil51side than on the lower thin-film coil11side and gradually decreases its width toward the lower thin-film coil11. The width of the magnetic pole end face26aon the upper thin-film coil51side defines the track width. The track width is about 0.06 to 0.12 μm, for example. The magnetic pole end face26ais positioned on the ABS30.

The main magnetic pole layer26includes a track width determining part having the magnetic pole end face26a, a wider part and a width extending part. The track width determining part has a fixed width regardless of the distance from the ABS30. The wider part is arranged at a position distanced more from the ABS30than is the track width determining part and has a width greater than that of the track width determining part. The wider part has the same width as that of the track width determining part at the boundary with the track width determining part, gradually increases the width as it is distanced more from the ABS30. The width extending part has a fixed width greater than the wider part. In this embodiment, a part from the magnetic pole end face26auntil the width begins to increase is defined as the track width determining part.

Further, as illustrated inFIG. 9, in the main magnetic pole layer26, an upper tilted surface26cand a lower tilted surface26eare formed in the track width determining part.

The upper tilted surface26cis formed in an ascending slope like shape distanced more from the substrate1as it is distanced more from the ABS30. The upper tilted surface26cis connected to the magnetic pole end face26aand an upper end face26d.

The lower tilted surface26eis formed in a descending slope like shape closer to the substrate1as it is distanced more from the ABS30. The lower tilted surface26eis connected to the magnetic pole end face26aand the lower end face26fof the wider part. The lower tilted surface26eis formed from the track width determining part to wider part. The lower end face26fis disposed on the nearest position to the substrate1in the main magnetic pole layer26.

Further, in the main magnetic pole layer26, nonmagnetic layers27,28are laminated on a part of the upper end face26dbetween an opposing shield part61and the upper yoke layer65which will be explained later, as also illustrated inFIG. 1.

A length of the above-described track width determining part from the ABS30is referred to as neck height. The neck height is about 0.05 to 0.3 μm, for example.

The gap layer29is formed along the upper tilted surface26cand the upper end face26dof the main magnetic pole layer26between the opposing shield part61, the insulating layer31and the main magnetic pole layer26, the nonmagnetic layers27,28. The gap layer29is formed so as to cover the upper tilted surface26cand the upper end face26d. The gap layer29is made of an insulating material such as alumina (Al2O3), nonmagnetic conductive material such as Ru, NiCu, Ta.

Next, the lower shield layer40and the write shield layer60will be explained. As illustrated inFIG. 1,FIG. 9, the lower shield layer40and the write shield layer60are disposed so as to sandwich the main magnetic pole layer26between them.

The lower shield layer40is arranged on the substrate1side of the main magnetic pole layer26. The lower shield layer40includes a leading shield part47and side shield parts47A arranged in the ABS30as illustrated also inFIG. 2and is a multiple shield layer in which the two shield parts overlie each other.

Further, the lower shield layer40has the connecting shield part41, a lower front shield part42, a linking shield part43, a first rear shield part44, a second rear shield part45, a third rear shield part46, and a partial lower seed layer91, in addition to the leading shield part47and the side shield part47A. The lower shield layer40is formed using a magnetic material made of a ferromagnetic body such as NiFe, CoNiFe, CoFe or the like.

The connecting shield part41and lower front shield part42are arranged closer to the ABS30than are the lower thin-film coil11. Besides, one part of the lower front shield part42overlies the connecting shield part41. The connecting shield part41is arranged at a position distanced from the ABS30. But, the lower front shield part42has a shield end face42aarranged within the ABS30(seeFIG. 9).

The linking shield part43is formed such as to straddle the turn parts11b,11d,11fof the lower thin-film coil11, and connects the connecting shield part41and the first rear shield part44to each other. The linking shield part43has a function as a return pole which backs the magnetic flux emitted from the main magnetic pole layer26.

The first, second, third rear shield parts44,45,46are arranged farther from the ABS30than are the turn parts11b,11d,11fof the lower thin-film coil11. The second rear shield part45overlies the first rear shield part44, the third rear shield parts46overlies the second rear shield part45. The first, second, third rear shield parts44,45,46form a three-stage structure in which their respective front side faces closer to the ABS30are equidistant from the ABS30. The first, second, third rear shield parts44,45,46has a function as a linking part which link the linking part43to the main magnetic pole layer26.

The leading shield part47corresponds to a first lower shield part according to the embodiment of the present invention. The leading shield part47is connected to the lower front shield part42and the side shield parts47A,47A are formed on its upper face on the opposite side. The leading shield part47has a shield end face47aarranged in the ABS30(seeFIG. 9).

The side shield parts47A,47A correspond to second lower shield parts according to the embodiment of the present invention. The side shield parts47A,47A are formed on the leading shield part47. The side shield parts47A,47A are arranged on both sides in the track width direction of the main magnetic pole layer26respectively. The side shield parts47A,47A also have shield end faces47Aa arranged in the ABS30respectively (seeFIG. 2). The side shield parts47A,47A and the leading shield part47are formed to surround the magnetic pole end face26avia a nonmagnetic thin-film25and arranged near the main magnetic pole layer26.

The partial lower seed layer91is a metal layer used as a ground when the side shield parts47A,47A are formed on the leading shield part47by electro plating. The partial lower seed layer91is formed by sputtering or the like under a dry environment. The partial lower seed layer91is formed using a magnetic material such as CoNiFe, CoFe, NiFe.

Further, the partial lower seed layer91is formed only in a partial area in a lower thin-film-like space having a very small thickness sandwiched between the leading shield part47and the side shield parts47A,47A. The whole partial lower seed layer91is arranged at a position distanced from the ABS30.

In more detail, the partial lower seed layer91has a partial arrangement structure. In other words, the partial lower seed layer91is arranged only on a later-described lower formation zone92B as illustrated inFIG. 17,FIG. 18. The lower formation zone92B corresponds to an area of the front surface of a multilayer body except a lower exception zone92A1at the stage before the formation of the ABS30. Further, at the stage after the formation of the ABS30, the lower formation zone92B corresponds to an area of the surface of the multilayer body except a lower absence zone92A2and recesses from the ABS30.

In the thin-film magnetic head300, all of a seed layer that is a ground when forming the side shield parts47A,47A is removed from the front surface of the lower absence zone92A2. The lower absence zone92A2is arranged in the above-described lower thin-film-like space and corresponds to a rectangular area having a depth D2along a later-described depth direction from a later-described planned line (or the ABS30). In the lower absence zone92A2, an end face91aof the partial lower seed layer91appears (seeFIG. 17,FIG. 21(b)). The end face91adoes not appear in the ABS30(seeFIG. 27,FIG. 30,FIG. 30).

Further, the write shield layer60will be explained. The write shield layer60corresponds to an upper shield layer according to the embodiment of the present invention. The write shield layer60has an opposing shield part61, an upper front shield part62, a linking shield part63, a rear shield part64and a wide upper seed layer93.

The opposing shield part61corresponds to a first upper shield part according to the embodiment of the present invention. The opposing shield part61has a shield end face61adisposed in the ABS30(seeFIG. 9). The opposing shield part61opposes the leading shield part47within the ABS30. Besides, a very small space which the gap layer29is arranged is formed in the shield end face61aof the opposing shield part61. A part of ABS30side of the gap layer29is formed in the very small space. The opposing shield part61is formed such as to oppose the main magnetic pole layer26, nonmagnetic layer27, and nonmagnetic layer28sequentially from the ABS30side through the gap layer29. The opposing shield part61has a flat upper face, to which the upper front shield part62is connected.

The upper front shield part62is arranged closer to the ABS30than are the upper thin-film coil51. This upper front shield part62will be explained with reference toFIG. 6,FIG. 7.

The upper front shield part62has a shield front end face62b, a shield upper end face62f, a shield connecting part62c, and a shield lower end face62r. The shield front end face62bis disposed in the ABS30. The shield front end face62bis exposed in the ABS30. InFIG. 6, a part with cross-hatching represents the shield front end face62b. The shield upper end face62fis disposed at a position distanced more from the substrate1than is the shield front end face62b. The side distanced more from the substrate1is also called an upper side and the side closer to the substrate1is also called a lower side. The shield upper end face62fis connected to the linking shield part63. The shield upper end face62fis formed along the direction intersecting the ABS30. In addition, the shield upper end face62fis formed separated from the ABS30. The shield upper end face62fhas a size smaller than that of the shield lower end face62r.

The shield connecting part62cis a part connecting the shield front end face62bto the shield upper end face62f. The whole part of the shield connecting part62cexcepting a connecting part62xwith the shield front end face62bis disposed at a position distanced from the ABS30.

The shield connecting part62chas a tilt structure tilted to be gradually distanced more from the ABS30as it gets closer, starting from the connecting part62x, to a connecting part62yconnected to the shield upper end face62f. The connecting part62xis disposed in the ABS30, but the connecting part62yis disposed at a position distanced from the ABS30and thus receds from the ABS30.

Further, as illustrated inFIG. 7, considering an imaginary flat surface99linking the connecting part62xand the connecting part62y, the flat surface99is a flat surface linking the shield front end face62band the shield upper end face62fat a shortest distance. The shield connecting part62chas a receding tilt structure tilted to be distanced more from the ABS30than is the flat surface99. Further, the shield connecting part62chas a lateral flat part62c1, a longitudinal flat part62c2, and a curved part62c3and has a structure that they are smoothly linked together into one body. The lateral flat part62c1is generally formed along the direction intersecting the ABS30. The longitudinal flat part62c2is generally formed along the ABS30.

The shield lower end face62ris formed along the direction intersecting the ABS30. The shield lower end face62rhas a size reaching the ABS30. The shield lower end face62rhas a size larger than that of the shield upper end face62f. The shield lower end face62ris connected with the opposing shield part61on the ABS30side, and connected with the insulating layer31on the rear side of the shield lower end face62rdistanced more from the ABS30.

The upper front shield part62has the above-described structure and therefore has an end face disposed in the ABS30that is smaller in size and in volume than that of the pre-trim front shield part62A (the upper side inFIG. 7). The pre-trim front shield part62A is a front shield part immediately before it is formed by performing a later-described trimming step. The pre-trim front shield part62A has the shield upper end face62freaching the ABS30and has a pre-trim front end face62a. Comparing the sizes of the pre-trim front end face62aand the shield front end face62b, the shield front end face62b<the pre-trim front end face62a.

Next, the linking shield part63will be explained. The linking shield part63is formed such as to straddle the turn part51g,51e,51cof the upper thin-film coil51. The linking shield part63is formed separated from the ABS30. The linking shield part63is connected to the upper front shield part62and the rear shield part64.

The rear shield part64is arranged at a position distanced more from the ABS30than is the turn part51g,51e,51cof the upper thin-film coil51. The rear shield part64is connected to the linking shield part63and the upper yoke layer65. A height of the rear shield part64is equal to a height of the upper front shield part62. Therefore, the rear shield part64forms a common flat surface59together with the upper thin-film coil51and shield upper end face62f.

The upper yoke layer65is connected to a rear side of the upper end face26din the main magnetic pole layer26, distanced more from the ABS30than is the nonmagnetic layers27,28. An upper end face of the upper yoke layer65is formed without level difference to an upper end face of the opposing shield part61. The upper end face of the upper yoke layer65forms a common flat surface59A (seeFIG. 32) together with the upper end face of the opposing shield part61.

The wide upper seed layer93is a metal layer used as a ground when forming the opposing shield part61on the main magnetic pole layer26by electro plating. The wide upper seed layer93is formed in an upper thin-film-like space having a very small thickness sandwiched between the main magnetic pole layer26, the nonmagnetic layers27,28and the opposing shield part61. The wide upper seed layer93does not have the partial arrangement structure and therefor appears in the ABS30as illustrated inFIG. 30,FIG. 31.

Moreover, the thin-film magnetic head300has a displacement suppression layer85. The displacement suppression layer85is connected an upper end face of the linking shield part63. The displacement suppression layer85is formed from a nonmagnetic material having a low coefficient of linear thermal expansion. For example, the displacement suppression layer85is preferably made of an inorganic or metal material, examples of which include SiC, AlN, Si3N4, and W (tungsten). It will be preferred in particular to use a nonmagnetic material having a high hardness for the displacement suppression layer85. For example, the displacement suppression layer85is preferably made of SiC, which has a Vickers hardness higher than that of alumina.

Further, the thin-film magnetic head300has a protective insulating layer90. The protective insulating layer90is formed using an insulating material such as alumina (Al2O3). The protective insulating layer90has an embedded part90aand a cover part90b. The embedded part90aand the cover part90bare formed in one body. The embedded part90acomes in contact with an all of the shield connecting part62c, and is embedded with no space between the shield connecting part62cand the ABS30. The cover part90bis formed so as to cover the linking shield part63and the displacement suppression layer85.

FIG. 10(a) toFIG. 14(a),FIG. 26(a),FIG. 28(a),FIG. 32(a) toFIG. 37(a) is sectional view corresponding toFIG. 1in respective step of manufacturing the thin-film magnetic head300, whileFIG. 10(b) toFIG. 14(b),FIG. 26(b),FIG. 28(b),FIG. 32(b) toFIG. 37(b) is front view similarly corresponding toFIG. 2.FIG. 15toFIG. 20,FIG. 29is a plan view illustrating a principal part of a multilayer body in a step of manufacturing the thin-film magnetic head300.FIG. 21(a),FIG. 21(b) toFIG. 22(a),FIG. 22(b) is a sectional view taken along the line21a-21a, the line21b-21b, the line22a-22a, the line22b-22bofFIG. 16toFIG. 19, respectively.FIG. 23(a),FIG. 23(b) toFIG. 25(a),FIG. 25(b),FIG. 27,FIG. 30toFIG. 31is a sectional view illustrating a principal part of multilayer body when the multilayer body is cut along a planned line, in a respective step of manufacturing the thin-film magnetic head300. In each drawing, “ABS” represents a planned line which the ABS30will be formed later.

First, the substrate1made of a ceramic material such as aluminum oxide-titanium carbide (Al2O3.TiC) is prepared. Subsequently, as illustrated inFIG. 10(a),FIG. 10(b), the insulating layer2made of an insulating material such as alumina (Al2O3) and the lower shield layer3made of a magnetic material are successively formed on the substrate1. The heating part8is formed when the insulating layer2is formed.

Then, the shield gap film4is formed by an insulating material such as to shield the MR device5. Here, an undepicted lead connected to the MR device5is formed, and the MR device5and the lead are covered with the shield gap film4. Thereafter, using a magnetic material and an insulating material, the upper shield layer6(the first shield part6a, the insulating part6b, the second shield part6c) is formed on the shield gap film4.

Next, the insulating layer7for separating the upper shield layer6and a recording head to be formed later from each other is formed by an insulating material such as alumina (Al2O3). The heat sensing part9is formed when the insulating layer7is formed. The foregoing steps yield a multilayer body for forming the recording head.

Subsequently, the lower shield layer40is formed by performing a lower shield layer forming step. In this embodiment, the lower shield layer forming step has a later-described first lower shield part forming step, a lower seed layer forming step and a second lower shield part forming step.

Further, in case of forming the lower shield layer40, first, a magnetic layer (having a thickness of about 0.6 μm) for forming the linking shield part43is formed by using a magnetic material such as NiFe or CoNiFe or the like, so as to form an insulating layer on the surface of the multilayer body, and the surface of the multilayer body is flattened by chemical mechanical polishing (hereinafter, referred to as “CMP”). This forms an opposing insulating layer17and the linking shield part43. Here, the linking shield part43is formed such as to be separated from the ABS30by 0.3 to 1 μm (about 0.5 μm in this embodiment).

Subsequently, an insulating layer18(having a thickness of about 0.1 μm to 0.3 μm) made of alumina (Al2O3) is formed on the whole surface of the multilayer body. Then, after applying a photoresist to the whole surface of the multilayer body, patterning is performed with a predetermined photomask, so as to form a resist pattern (not depicted). Using this resist pattern as a mask, etching such as RIE is performed, so as to selectively perforate the insulating layer18.

Next, a connecting shield part forming step is performed. In this step, by frame plating method, using a magnetic material made of a ferromagnetic body such as NiFe or CoNiFe or the like, the connecting shield part41and the first rear shield part44are formed by a thickness of about 1-1.5 μm each.

Next, as illustrated inFIG. 11(a),FIG. 11(b), an insulating layer19(having a thickness of about 0.02 μm to 0.3 μm, preferably about 0.1 μm to 0.2 μm) made of alumina (Al2O3) is formed on the whole surface of the multilayer body by CVD (Chemical Vapor Deposition) according to an atomic layer method. The insulating layer19is formed so as to cover the connecting shield part41and the first rear shield part44.

Then, a conductor layer70is formed by performing a conductor layer forming step. The conductor layer70is formed to form the lower thin-film coil11. In this step, first, a conductor layer70is formed between the connecting shield part41and the first rear shield part44by frame plating. The conductor layer70is formed such as to have two interstices70abetween the connecting shield part41and the first rear shield part44and come into contact with the connecting shield part41and the first rear shield part44through the insulating layer19without gaps. The conductor layer70is an intermittent conductor layer, since it is provided with interstices70a.

Next, as illustrated inFIG. 12(a),FIG. 12(b), a photoresist layer80(having a thickness of about 1.5 μm to 2.5 μm) is formed so as to be embedded the two interstices70ain the conductor layer70. Next, an insulating film20adapted to cover the surface of the multilayer body is formed using alumina (Al2O3) by a thickness of about 3 μm to 4 μm. Subsequently, the surface of the multilayer body is polished by CMP until the connecting shield part41and the first rear shield part44emerge, so as to become flat.

This forms the lower thin-film coil11as illustrated inFIG. 13(a),FIG. 13(b). Besides, an opposing insulating layer20is also formed on the side closer to the ABS30than is the connecting shield part41.

Subsequently, as illustrated inFIG. 14(a),FIG. 14(b), an insulating layer21(having a thickness of about 0.3 μm to 0.7 μm) made of alumina (Al2O3) is formed on the whole surface of the multilayer body. After that, the insulating layer21is selectively perforated.

Next, the lower front shield part42and the second rear shield part45are formed to overlie in the opened part each in a thickness of 0.5 μm to 1.2 μm by the frame plating method using a magnetic material made of a ferromagnetic body such as NiFe or CoNiFe. After that, the surface of the multilayer body is polished by CMP so as to become flat.

Then, as illustrated inFIG. 26(a),FIG. 26(b), the base insulating layer24is formed using an insulating material such as alumina (Al2O3) or the like. The heating part23is formed when the base insulating layer24is formed. After that, the base insulating layer24is selectively perforated.

The leading shield part47is formed by performing a first lower shield part forming step. In this case, the leading shield part47is formed at a lower shield planned area47B in a thickness of 0.5 μm to 1.0 μm by the frame plating method using a magnetic material made of a ferromagnetic body such as NiFe or CoNiFe. The lower shield planned area47B is an area including a later-described planned line. As illustrated inFIG. 26, the lower shield planned area47A is disposed on an ABS30side of the opened part. Besides, the third rear shield part46is formed on a part of the opened part, separated from the ABS30side.

Then, as illustrated inFIG. 15, the leading shield part47is formed on the upper face of the multilayer body. However, the ABS30has not been formed yet at this moment. Therefore, the planned line can be assumed on the surface of the multilayer body as illustrated inFIG. 15. InFIG. 15, the line indicated by a broken line (the line indicated by “ABS”) represents the planned line. The planned line is formed on the straight line along the ABS30formed later. The leading shield part47at this moment includes the planned line and also includes a part which will be removed at the completion, and therefore has a size larger than that at the completion.

Next, a lower seed layer forming step is performed to form the partial lower seed layer91. In this embodiment, the lower seed layer forming step includes a later-described wide lower seed layer forming step and a lower seed layer removing step.

Then, in the wide lower seed layer forming step, a wide lower seed layer91A is formed on the upper face of the multilayer body as illustrated inFIG. 16. The wide lower seed layer91A is a metal layer used as a ground when forming the side shield part47A later by electro plating. The wide lower seed layer91A is arranged on later-described lower exception zone92A1and lower formation zone92B on the upper face of the multilayer body.

Subsequently, a lower seed layer removing step is performed. In this step, an excepted lower seed layer91B of the wide lower seed layer91A is removed by etching or the like as illustrated inFIG. 17. The excepted lower seed layer91B corresponds to a part with dots inFIG. 16. The excepted lower seed layer91B corresponds a part of the wide lower seed layer91A formed on the lower exception zone92A1. By the removal of the excepted lower seed layer91B, the wide lower seed layer91A becomes the partial lower seed layer91. When cutting, along the planned line, the multilayer body when the excepted lower seed layer91B is removed, the end face91aof the partial lower seed layer91existing behind the section can be viewed as illustrated inFIG. 24(a).

Further, in the lower seed layer removing step, the lower exception zone92A1is set in a band-shaped area along the ABS30including the whole planned line as illustrated inFIG. 17. Further, as illustrated also inFIG. 21(b), a rectangular area having a depth D1along the depth direction from an exception start line S1is secured as the lower exception zone92A1(since the depth D1is larger than the depth D2, D1>D2). The depth direction means the direction separating from the ABS30toward the position where the upper thin-film coil51will be formed later on the substrate1(more specifically, on the surface of the multilayer body). The exception start line S1is set at a portion that is shifted outward (toward the opposite direction to the depth direction) from the planned line by, for example, about 0.01 to 0.1 μm.

By the performance of the lower seed layer removing step, the seed layer is removed from the area of the surface of the leading shield part47including the whole planned line, and an area where the seed layer does not exist (an area slightly larger than the above-described lower absence zone92A2) is formed along the planned line. At this moment, the surface is exposed without being covered with the seed layer in the area of the leading shield part47including the whole planned line.

Next, a second lower shield part forming step is performed to form the side shield parts47A,47A as illustrated inFIG. 18,FIG. 22(a),FIG. 24(b). In this case, the side shield parts47A,47A are formed in the lower shield planned area47A by frame plating method using a magnetic material made of a ferromagnetic body such as NiFe or CoNiFe by a thickness of about 0.5 μm to 1.0 μm each. Parts with dots inFIG. 18correspond to the side shield parts47A,47A.

In this case, even after the lower seed layer removing step is performed, the partial lower seed layer91is formed in a part of the lower shield planned area47A. Therefore, by growth of the plating film using the partial lower seed layer91as the ground, the side shield parts47A,47A are formed on the partial lower seed layer91.

Note that the side shield parts47A,47A are not formed in a very narrow area95illustrated inFIG. 18. The very narrow area95means an area with a small width where the magnetic pole end face26aof the main magnetic pole layer26will be arranged later.

After that, as illustrated inFIG. 19,FIG. 25(a), a nonmagnetic thin-film25is formed so as to cover the base insulating layer24and the side shield part47A,47A. The nonmagnetic thin-film25is formed by sputtering with a nonmagnetic metal material such as Ru, NiCr, or NiCu, or an insulating material such as alumina. The nonmagnetic thin-film25is also formed at the very narrow area95.

Here, as illustrated inFIG. 18,FIG. 22(a), side faces of the side shield part47A,47A appear in the very narrow area95. On the side faces and also on the partial lower seed layer91in the very narrow area95, the nonmagnetic thin-film25is formed. Therefore, illustrating the section of the multilayer body along the depth direction passing through the very narrow area95, the front surface and the section of the nonmagnetic thin-film25appears in the section of the multilayer body as illustrated inFIG. 22(b).

Subsequently, as illustrated inFIG. 28(a),FIG. 28(b), a magnetic layer75having a thickness of about 0.4 to 0.8 μm is formed by frame plating method with a magnetic material made of a ferromagnetic body such as CoNiFe, CoFe, NiFe. By this magnetic layer75, the main magnetic pole layer26will be formed later.

After that, a nonmagnetic layer77(having a thickness of about 0.04 to 0.1 μm) is formed on the whole surface of the multilayer body by sputtering with a metal material such as Ru, NiCr, or NiCu. The nonmagnetic layer77will partly be etched away later, so as to become the above-mentioned nonmagnetic layer27. Further, using an inorganic insulating material such as alumina (Al2O3) or silicon oxide, a nonmagnetic layer78(having a thickness of about 0.1 to 0.3 μm) is formed on the whole surface of the multilayer body. The nonmagnetic layer78will partly be etched away later, so as to become the above-mentioned nonmagnetic layer28.

Subsequently, after applying a photoresist to the whole surface of the multilayer body, patterning with a predetermined photomask is performed, so as to form a resist pattern81near the ABS30.

Next, using the resist pattern81as a mask, etching such as RIE, for example, is performed, so as to remove a part of the nonmagnetic layer78. The etching in this case is performed such as to stop at the time when the bottom part of a groove formed by etching reaches the upper face of the nonmagnetic layer77. To this aim, a material yielding an etching rate lower than that of the nonmagnetic layer77is used for the nonmagnetic layer78.

After that, the resist pattern81is removed. Then, using the remaining nonmagnetic layer78as a mask, a part of the nonmagnetic layer77is etched away by IBE, for example. Further, using the remaining nonmagnetic layer77as a mask, a part of the nonmagnetic layer75is etched away by IBE, for example. This step forms the upper tilted surface26con the ABS side of the magnetic layer75, and the main magnetic pole layer26is formed, as illustrated inFIG. 25(b).

Subsequently, as illustrated inFIG. 27,FIG. 32(a),32(b), the gap layer29(having a thickness about 250 Å to 350 Å) is formed on the whole surface of the multilayer body by sputtering or CVD with an insulating material such as alumina (Al2O3) or a nonmagnetic conductive material such as Ru, NiCu, or Ta.

Further, an undepicted stopper film is formed by sputtering, for example, and a nonmagnetic film is formed thereon. Subsequently, an undepicted photoresist is applied to the whole surface of the multilayer body. Then, patterning with a predetermined photomask is performed, so as to form an undepicted resist pattern. Using this resist pattern as a mask, the nonmagnetic film is etched by RIE, for example. This etching is performed such as to stop when the bottom part of a groove formed by etching reaches the upper face of the stopper film. Then, after removing the resist pattern that is not depicted, the remaining nonmagnetic film is used as a mask for partly etching the gap layer29, nonmagnetic layer77and nonmagnetic layer78away by RIE or the like. Here, the gap layer29, nonmagnetic layer77and nonmagnetic layer78are partly removed, so as to secure a space for forming the above-mentioned upper yoke layer65.

Subsequently, the write shield layer60is formed by performing an upper shield layer forming step. In this embodiment, the upper shield layer forming step has a later-described first upper shield part forming step, a second upper shield part forming step, a linking shield part forming step and a trimming step.

First, the opposing shield part61is formed by performing the first upper shield part forming step. In this step, first, as illustrated inFIG. 29,FIG. 30, a wide upper seed layer93is formed on the main magnetic pole layer26in the surface of the multilayer body. Subsequently, an electro plating, using this wide upper seed layer93as a ground, is performed, a magnetic layer is formed on the surface of the multilayer body. This magnetic layer is formed using a magnetic material made of a ferromagnetic body such as CoNiFe, CoFe, CoFeN, NiFe or the like by a thickness of about 0.5 to 1.2 μm. This magnetic layer will later form the opposing shield part61and the upper yoke layer65.

Subsequently, an insulating layer (having a thickness of about 1 to 3 μm) is formed on the whole surface of the multilayer body using an insulating material such as alumina (Al2O3). Further, the whole surface of the multilayer body is polished by CMP until a surface of the magnetic layer emerges, so as to be made flat. This forms the opposing shield part61, the upper yoke layer65and an insulating layer31, as illustrated inFIG. 31,FIG. 32(a),FIG. 32(b). At this time, the surface of the multilayer body is polished such that the opposing shield part61has a thickness of about 0.5 to 1.0 μm.

Next, a second upper shield part forming step is performed. In this step, as illustrated inFIG. 33(a),FIG. 33(b), at parts of the surface of the multilayer body where the upper front shield part62and the rear shield part64will be formed, the pre-trim front shield part62A and the rear shield part64are formed respectively. In this event, the pre-trim front shield part62A is disposed in the ABS30and therefore corresponds to the second upper shield part according to the embodiment of the present invention. In the second shield part forming step, the pre-trim front shield part62A and the rear shield part64are formed by, for example, frame plating method using a magnetic material made of a ferromagnetic body such as NiFe or CoNiFe. In this event, the space between the pre-trim front shield part62A and the rear shield part64is made to range from about 3.0 μm to about 3.5 μm.

In addition, the pre-trim front shield part62A is formed to be connected to the opposing shield part61and disposed in the ABS30. The pre-trim front shield part62A has a shape illustrated on the upper side inFIG. 7. In the pre-trim front shield part62A, the whole front end face62ais disposed in the ABS30.

Then, first, as illustrated inFIG. 34(a),FIG. 34(b), a conductor layer71is formed on the surface of multilayer body between the first shield part (pre-trim front shield part62A) and the rear shield part64. This conductor layer71will later form the upper thin-film coil51. The conductor layer71is formed such as to have two interstices71aand come into contact with the first shield part (pre-trim front shield part62A) and the rear shield part64through an interlayer insulating layer32without gaps. The conductor layer71is an intermittent conductor layer, since it is provided with interstices71a.

After that, a photoresist layer55(having a thickness of about 2 μm to 3 μm) is formed so as to cover the two interstices71ain the conductor layer71, a cover insulating film adapted to cover the surface of the multilayer body is formed using alumina (Al2O3) by a thickness of about 3 μm to 4 μm. Subsequently, the surface of the multilayer body is polished by CMP until the pre-trim front shield part62A and the rear shield part64emerge, so as to become flat.

This forms the upper thin-film coil51and the photoresist layer55, as illustrated inFIG. 35(a),FIG. 35(b). In this event, flattening of the surface of the multilayer body is performed so that the thickness of the upper thin-film coil51is about 1.0 μm to 1.8 μm. Besides, the above-described common flat surface59is formed by the flattening of the surface of the multilayer body.

Subsequently, as illustrated inFIG. 36(a),FIG. 36(b), an insulating layer34is formed on the whole surface of the multilayer body using an insulating material such as alumina (Al2O3), and the insulating layer34is partially perforate. After that, the linking shield part forming step is performed. In this step, the linking shield part63is formed by frame plating method using a magnetic material made of a ferromagnetic body such as NiFe, CoNiFe or the like. The linking shield part63is formed so as to connect to the pre-trim shield part62A. The linking shield part63is formed so as to straddle the turn parts51g,51e,51cof the upper thin-film coil51through the insulating layer34.

Further, the linking shield part63is receded from the front end face30h(also receded from the ABS30) and formed at a position distanced from the ABS30. In other words, the linking shield part63is formed at a position where a receding space63his ensured between the linking shield part63and the ABS30. The receding space63hbecomes an elongated part having a width, for example, about 0.4 μm to 0.7 μm along the ABS30and the same height as that of the linking shield part63.

Next, a trimming step is performed. In this step, as illustrated inFIG. 37(a),FIG. 37(b), IBE is performed by applying ion beams IB from the upper direction using the linking shield part63as a mask to cut off the part of the pre-trim front shield part62A which is not covered with the linking shield part63. Since the part of the pre-trim front shield part62A on the ABS side is not covered with the linking shield part63, the part on the ABS side of the pre-trim front shield part62A is cut off by performing IBE. In this event, IBE is performed in a manner to leave a part of the pre-trim front end face62aof the pre-trim front shield part62A disposed in the ABS30. Thus, as shown inFIG. 7, the above-described shield front end face62bis formed of the part of the pre-trim front end face62awhich has not been cut off but left. Further, IBE is performed in a manner to cause the shield connecting part62chaving the above-described receding tilt structure to appear.

Though the linking shield part63itself is used as a mask in the above-described trimming step, a mask such as a photoresist or the like covering the upper face of the linking shield part63may be used instead of using the linking shield part63. More specifically, a mask equal in size to the linking shield part63may be formed on the upper face of the linking shield part63using photoresist or the like, and the part of the pre-trim front shield part62A which is not covered with the linking shield part63may be cut off using the mask.

Further, with chemical action of gas plasma used in etching, the etching can proceed not only in the vertical direction (the longitudinal direction inFIG. 37) but also in the horizontal direction (the lateral direction inFIG. 37) of the pre-trim front shield part62A. Therefore, it is preferable to perform non-active IBE, namely, ion milling in the trimming step. Etching performed utilizing physical impact when inactive ions are applied is also called ion milling for distinction from reactive ion etching.

Subsequently, as illustrated inFIG. 1, the displacement suppression layer85is formed. After that, the protective insulating layer90is formed by an insulating material such as alumina (Al2O3) so as to cover the displacement suppression layer85. After that, the ABS30is formed by performing polishing processing or mechanical processing to the front end face30h, whereby the thin-film magnetic head300is completed.

The protective insulating layer90is formed such as to come into contact with an entire the shield connecting part62cand be embedded without gap between the shield connecting part62cand the ABS30.

(Operation and Effect of Thin-Film Magnetic Head300)

As in the foregoing, the thin-film magnetic head300has the multiple shield layer in which the leading shield part47overlie the side shield parts47A,47A. The side shield parts47A,47A are formed on the leading shield part47via the partial lower seed layer91. The partial lower seed layer91has the partial arrangement structure in which it is arranged only on the lower formation zone92B and receds from the ABS30. Therefore, the partial lower seed layer91does not appear in a joint part of the leading shield part47and the side shield parts47A,47A in the ABS30.

In the thin-film magnetic head300, the lower absence zone92A2is further formed between the leading shield part47and the side shield parts47A,47A, and the end face91aof the partial lower seed layer91appears in the lower absence zone92A2without appearing in the ABS30(seeFIG. 31).

The leading shield part47and the side shield parts47A,47A are formed mainly by electro plating and are therefore in common in the direction of crystal of the magnetic material. However, the partial lower seed layer91is formed by spluttering or the like and is therefore different in the direction of crystal of the magnetic material and in magnetic characteristics from the leading shield part47and the side shield parts47A,47A.

However, since the partial lower seed layer91has the partial arrangement structure in the thin-film magnetic head300, a seed layer different in magnetic characteristics from the leading shield part47and the side shield parts47A,47A does not exists between the leading shield part47and the side shield parts47A,47A in the ABS30. This rarely causes a phenomenon that a component of the magnetic flux emitted from the magnetic pole end face26aspreading in the track width direction remains without being absorbed by the leading shield part47or the side shield parts47A,47A (this phenomenon is referred also to as residual of magnetic flux in this embodiment).

Accordingly, there rarely occurs a phenomenon that data recorded on a recording medium is erased or rewritten by the magnetic flux remaining without being absorbed by the leading shield part47or the side shield parts47A,47A.

As described above, the thin-film magnetic head300has the multiple shield layer which is arranged in the ABS30but in which ATE and WATE caused by the multiple shield layer can be improved.

On the other hand, the effect of preventing the residual of magnetic flux can be achieved only by partially retracting the seed layer from the ABS30. However, in order to more surely prevent the residual of magnetic flux, it is preferable to set the lower absence zone92A2in the band-shaped area over the entire width direction of the ABS30as in the thin-film magnetic head300. This makes all the part of the end face91aof the partial lower seed layer91appear in the lower absence zone92A2but not appear in the ABS30. This achieves a structure in which the seed layer different in magnetic characteristics from the leading shield part47and the side shield parts47A,47A does not exist at all between them. This structure can surely prevent the residual of magnetic flux and thus can more surely improve ATE and WATE.

Meanwhile, the thin-film magnetic head300is structured such that only the upper front shield part62is formed as the magnetic layer which is to be disposed between the opposing shield part61and the linking shield part63. Therefore, as compared to the case where the two magnetic layers are formed between the opposing shield part61and the linking shield part63, the length of the magnetic path along the top-down direction is shorter so that the magnetic path length is able to be reduced in the thin-film magnetic head300.

Hence, the thin-film magnetic head300is able to improve the flux rise time, non-linear transition shift (NLTS) characteristic, overwrite characteristic, and the like of the recording head, and follow rapid changes in recording signals having a high frequency and changing fast. This makes the thin-film magnetic head300suitable as a recording head for hard disk drives mounted to servers in particular.

In addition, the upper front shield part62has a lateral width capable of reaching, from the ABS30, the upper thin-film coil51via the interlayer insulating layer32. Therefore, even though the write shield layer60has a different-distance structure, the front shield part62is surely connected to both of the opposing shield part61and the linking shield part63. Accordingly, the opposing shield part61opposing the main magnetic pole layer26and the linking shield part63straddling the turn parts51g,51e,51cof the upper thin-film coil51are liked together as a continuous line and are able to form the magnetic circuit as a continuous line. Note that the different-distance structure means a structure that the respective distances of the opposing shield part61and the linking shield part63from the ABS30are different because the opposing shield part61is disposed in the ABS30and the linking shield part63is receded from the ABS30.

A structure is discussed here which is intended to surely connect both of the opposing shield part61and the linking shield part63by the upper front shield part62in the different-distance structure of the write shield layer60. Since the sizes of the upper end face and the lower end face are maximum when the whole front end face is disposed in the ABS30as in the pre-trim front shield part62A, it is preferable that the whole front end face is disposed in the ABS30like the pre-trim front shield part62A in order to realize the aforementioned structure.

However, this causes the pre-trim front end face62ato be largely exposed in the ABS30. The upper front shield part62and the pre-trim front shield part62A are formed of a magnetic material made of a ferromagnetic body such as CoNiFe, CoFe, CoFeN, NiFe or the like. Therefore, if the whole pre-trim front end face62ais exposed in the ABS30like the pre-trim front shield part62A, the pre-trim front shield part62A will be affected more strongly when the photoresist layer55expands due to the heat generation of the upper thin-film coil51.

Since the frying height is very small, collision between the thin-film magnetic head300and the recording medium can occur even when only a limited and small part of the pre-trim front end face62aprojects. That the whole pre-trim front end face62ais exposed in the ABS30means that many such small parts which will project exist in the ABS30, which means that there are accordingly many projecting forms which can collide with the recording medium and collision between the thin-film magnetic head300and the recording medium is more likely to occur.

Hence, in the thin-film magnetic head300, the upper front shield part62having the structure illustrated on the lower side inFIG. 7is formed. Thus, the part exposed in the ABS30is the shield front end face62b.

Further, in the upper front shield part62, the shield upper end face62fis disposed at a position distanced more from the substrate1than is the shield front end face62b, and the upper front shield part62has the shield connecting part62cconnecting the shield front end face62bto the shield upper end face62f. In such a structure, the front end face disposed in the ABS30is smaller in size than that when the shield upper end face62freaches the ABS30, namely, the pre-trim front shield part62A as illustrated on the upper side inFIG. 7. Therefore, provision of the upper front shield part62makes it possible to suppress the situation that the thin-film magnetic head300collides with the recording medium.

Hence, the thin-film magnetic head300is able to restrain the write shield layer60from projecting as the upper thin-film coil51generate heat especially. Consequently, the thin-film magnetic head300is very unlikely to be damaged by the protrusion of the recording head and thus can approach recording media.

While the thin-film magnetic head300is incorporated in an undepicted slider, the flying height of the slider from the recording medium surface can be reduced. Therefore, the thin-film magnetic head300can enhance the resolution of recording and reproducing heads, thereby improving their signal-to-noise ratio. This can also increase the recording density of the thin-film magnetic head300.

On the other hand, the upper front shield part62is formed, after the formation of the linking shield part63, by cutting off a part thereof on the ABS30side where the linking shield part63is not in contact therewith. For this reason, though the part exposed in the ABS30is small, the shield upper end face62fis surely ensured, resulting in a structure in which the upper front shield part62and the linking shield part63can be surely connected.

Further, when cutting off the part of the upper front shield part62on the ABS30side, the shield front end face62bis ensured so that a part of the pre-trim front end face62ais left as the shield front end face62bwithout cutting off the whole pre-trim front end face62a. If IBE proceeds to the degree that the shield front end face62bis not ensured when cutting off the part of the pre-trim front shield part62A on the ABS30side, the shield lower end face62rcan also be cut off. In this case, the part which is to be connected to the opposing shield part61becomes smaller, so that the connection between the opposing shield part61and the upper front shield part62can be insufficient. However, there is no such possibility in the thin-film magnetic head300.

Further, the upper front shield part62has the shield connecting part62c, and the shield connecting part62chas the tilt structure. Therefore, the upper front shield part62has a structure which can be surely formed by the above-described IBE from the upper direction. Without the tilt structure, for example, when a surface part extending from the shield front end face62bto the shield upper end face62fis bent in an S-shape, it is difficult to form the upper front shield part62by IBE. However, in the thin-film magnetic head300, there is no such possibility and the upper front shield part62is able to be surely formed by IBE from the upper direction.

Further, since the shield connecting part62chas the receding tilt structure, the volume of the upper front shield part62is reduced as compared to the case without the receding tilt structure. This further suppresses the possibility of projection of the upper front shield part62.

Further, the shield connecting part62chas the lateral flat part62c1. The lateral flat part62c1is generally formed along the direction intersecting the ABS30. Accordingly, the shield connecting part62cis able to surely receive the pressure received in the longitudinal direction from the embedded part90aof the protective insulating layer90as compared to the case without the lateral flat part62c1. Accordingly, in the thin-film magnetic head300, the embedding state of the protective insulating layer90is stable.

Additionally, the shield connecting part62chas the longitudinal flat part62c2. The longitudinal flat part62c2is generally formed along the ABS30. Accordingly, the upper front shield part62has a structure which can be surely formed by IBE from the upper direction or the like to the pre-trim front shield part62A.

As has been described, in the thin-film magnetic head300, the magnetic path length can be reduced and projection of a part of the ABS30can be suppressed, so that both of the suppression of projection of a part of the medium-opposing surface and the reduction in magnetic path length can be realized. Accordingly, the thin-film magnetic head300is configured such that the projection of a part of the ABS30can be suppressed without affecting the reduction in magnetic path length.

Since the lower thin-film coil11and upper thin-film coil51have the variable width structures as mentioned above, current flows are less likely to be obstructed, whereby the resistance value is able to be restrained from rising. Accordingly, generation of heat from the lower thin-film coil11and the upper thin-film coil51are able to be suppressed effectively in the thin-film magnetic head300.

MODIFIED EXAMPLE 1

The above-described thin-film magnetic head300may have the upper front shield part62B as illustrated inFIG. 8(a) in place of the above-described upper front shield part62. The upper front shield part62B is different in that it has a shield connecting part62din place of the shield connecting part62c, as compared with the upper front shield part62. The shield connecting part62dis different in that it is not have the lateral flat part62c1, as compared with the shield connecting part62c.

The thin-film magnetic head300may have the upper front shield part62D as illustrated inFIG. 8(b) in place of the upper front shield part62. The upper front shield part62D is different in that it has a shield connecting part62ein place of the shield connecting part62c, as compared with the upper front shield part62. The shield connecting part62eis different in that it is not have the longitudinal flat part62c2, as compared with the shield connecting part62c.

In both of the case where the upper front shield part62B is provided and the case where the upper front shield part62D is provided, the shield front end face62bis disposed in the ABS30and the size of the part thereof exposed in the ABS30is reduced as compared to that of the pre-trim front shield part62A. Therefore, the possibility of projection of the upper front shield parts62B,62D is surely suppressed as compared to the pre-trim front shield part62A. Accordingly, both of the suppression of projection of a part of the medium-opposing surface and the reduction in magnetic path length can be realized in both of the case where the upper front shield part62B is provided and the case where the upper front shield part62D is provided.

MODIFIED EXAMPLE 2

In the above-described embodiment, the partial lower seed layer91is formed by performing the wide lower seed layer forming step and the lower seed layer removing step. More specifically, the partial lower seed layer91is formed by forming the wide lower seed layer91A on the surface of the multilayer body and then removing an unrequired part of the wide lower seed layer91A.

However, the partial lower seed layer91can be formed also as in the following manner. Specifically, a mask is formed in advance on the lower exception zone92A1using a photoresist or the like, sputtering is performed, and then the mask is removed. Thus, the seed layer is formed only in a required area, so that the formed seed layer can be used as the partial lower seed layer91. This eliminates the needs to remove the unrequired part of the seed layer, thereby preventing waste of the material of the seed layer.

Second Embodiment

The above-described thin-film magnetic head300has the write shield layer60, and the write shield layer60has the opposing shield part61. The opposing shield part61is formed on the wide upper seed layer93on the main magnetic pole layer26. However, the wide upper seed layer93does not have the partial arrangement structure as that of the partial lower seed layer91. The wide upper seed layer93therefore appears in the ABS30as illustrated inFIG. 30,FIG. 31.

In the case of such a thin-film magnetic head300, even if the residual of magnetic flux on the side closer to the substrate1than is the main magnetic pole layer26(referred also to as lower residual) can be prevented, the residual of magnetic flux on the side more distanced from the substrate1than is the main magnetic pole layer26(referred also to as upper residual) could not be prevented.

Hence, in order to prevent the upper residual, it is preferable to form a seed layer having the partial arrangement structure also on the side more distanced from the substrate1than is the main magnetic pole layer26. For example, it is preferable to form a partial upper seed layer93A illustrated inFIG. 38in place of the above-described wide upper seed layer93.

The partial upper seed layer93A is formed in a partial area of the upper thin-film-like space having a very small thickness between the main magnetic pole layer26and the opposing shield part61. Further, the whole partial upper seed layer93A is arranged at a position distanced from the ABS30.

The partial upper seed layer93A has the partial arrangement structure in which it is arranged only on a later-described upper formation zone94B. The upper formation zone94B corresponds to an area of the surface of the multilayer body except an upper exception zone94A1at the stage before the formation of the ABS30. At the stage after the formation of the ABS30, the upper formation zone94B corresponds to an area of the surface of the multilayer body except an upper absence zone94A2and recedes from the ABS30. In this embodiment, the upper absence zone94A2is set in an area having the same shape and the same size as those of the lower absence zone92A2.

In the thin-film magnetic head300, all the seed layer is removed from the surface in the upper absence zone94A2. The upper absence zone94A2is arranged in the above-described upper thin-film-like space, and an end face93aof the partial upper seed layer93A appears in the upper absence zone94A2. The end face93adoes not appear in the ABS30(seeFIG. 40).

In the case where the thin-film magnetic head300has the partial upper seed layer93A, a later-described upper seed layer forming step is performed in the above-described upper shield layer forming step. Further, in the first upper shield part forming step, the opposing shield part61is formed on the partial upper seed layer93A. Further, in the upper seed layer forming step, a wide upper seed layer forming step and an upper seed layer removing step are performed.

Further, by performing the wide upper seed layer forming step as in the first embodiment, the wide upper seed layer93similar to that in the first embodiment is formed. Then, by performing the upper seed layer removing step, an excepted upper seed layer (not illustrated) of the wide upper seed layer93is removed. The excepted upper seed layer corresponds to a part of the wide upper seed layer93formed on the upper exception zone94A1. The upper exception zone94A1is set in an area having the same shape and the same size as those of the above-described lower exception zone92A1.

In the above-described manner, the partial upper seed layer93A can be obtained. Thereafter, through the same steps as those in the foregoing, the thin-film magnetic head300is manufactured.

In the case of this thin-film magnetic head300, the partial upper seed layer93A has the partial arrangement structure as that of the partial lower seed layer91and therefore the partial upper seed layer93A does not appear in the ABS30. Accordingly, the thin-film magnetic head300can surely prevent the upper residual as well as the lower residual. Therefore, the thin-film magnetic head300can more surely improve ATE and WATE caused by the multiple shield layer.

This thin-film magnetic head300has a structure in which the partial upper seed layer93A does not exist on the main magnetic pole layer26. In such a structure, it is preferable to form the gap layer29using a nonmagnetic conductive material such as Ru, NiCu, Ta into a metal gap layer so as to promote the growth of the plating film in order that the opposing shield part61is formed on the main magnetic pole layer26.

This invention is not limited to the foregoing embodiments but various changes and modifications of its components may be made without departing from the scope of the present invention. Besides, it is clear that various embodiments and modified examples of the present invention can be carried out on the basis of the foregoing explanation. Therefore, the present invention can be carried out in modes other than the above-mentioned best modes within the scope equivalent to the following claims.