JPH06101098B2 - Thin film magnetic head and manufacturing method thereof - Google Patents

Description

The present invention relates to a thin film magnetic head used for in-plane recording / reproducing and a method for manufacturing the same, and a first magnetic layer, a magnetic gap layer, and In a thin film magnetic head in which a conductor coil, an insulating layer and a second magnetic layer are laminated, and one ends of the first magnetic layer and the second magnetic layer are opposed to each other via a magnetic gap, a track width of the first magnetic layer By providing inclined surfaces that are downwardly inclined from the magnetic gap side toward the substrate in the corners at both ends in the direction, the electromagnetic conversion area in the track width direction is substantially reduced, and it is possible to reduce the track width. The recording density can be improved.

<Prior Art> Recording in response to an increase in storage density and an increase in writing / reading speed in an external storage device of a computer. Thin film magnetic heads have been used to improve the reliability of reproduction. As shown in FIG. 6, the general structure of a conventional thin film magnetic head for in-plane recording / reproducing is, as shown in FIG. 6, an underlayer made of Al ₂ O ₃ or the like on a substrate 1 made of Al ₂ O ₃ —TiC or the like. Through 2,
The first magnetic layer 3 is formed, and Al ₂ O ₃ is formed on the first magnetic layer _3.
A magnetic gap layer 4 made of a non-magnetic material such as, a conductor coil 5 is formed on the magnetic gap layer 4, and a second magnetic layer 7 is formed on an insulating layer 6 formed on the conductor coil 5. And a protective layer 8 is provided on the second magnetic layer 7. The first magnetic layer 2 and the second magnetic layer 7 have their front ends opposed to each other via the magnetic gap G _{1 formed} by the magnetic gap layer 4 and their rear ends coupled to each other. The second magnetic layer 7 slightly rises from the coupling portion with the first magnetic layer 3 and extends in the front-rear direction to form a branch path.
71, the end surface 71a of the branch path 71 is brought close to the end surface 3a of the first magnetic layer 3 in the vicinity of the sliding contact surface with the magnetic recording medium running in the direction of the arrow a, and the magnetic gap required for recording and reproduction is formed. G ₁ is formed. The conductor coil 5 includes the first magnetic layer 3 and the second magnetic layer 3.
Is formed so that the coupling portion of the magnetic layer 7 of FIG.

The underlayer 2, the first magnetic layer 3, the magnetic gap layer 4, the conductor coil 5, the insulating layer 6, the second magnetic layer 7, and the protective layer 8.
Are sequentially stacked by a thin film forming process, a high precision pattern forming technique called photolithography, and a precision processing technique.

Here, since the second magnetic layer 7 is formed on the first magnetic layer 3 after the first magnetic layer 3 is formed, as shown in FIG. 7, the first magnetic layer 3 is formed in order to secure a manufacturing process margin. The track width direction length l ₁ of the second magnetic layer 7 must be longer than the track width direction length l _{2 of} the second magnetic layer 7. Clearances d ₁ and d ₂ are generated due to the difference between the heights l ₁ and l ₂ .

<Problems to be Solved by the Invention> By the way, in an external storage device of a computer,
In order to increase the storage density, the track narrowing has been promoted, and a thin film magnetic head used for this has been required to be capable of dealing with the track narrowing.

However, in the conventional thin film magnetic head, the first magnetic layer 3
Has a width l _{1 in} the track width direction larger than the width l _{2 in} the track width direction of the second magnetic layer 7, and the widths l ₁ , l at both ends of the first magnetic layer 3 in the track width direction. clearance d _1, d ₂ due to the difference of ₂ is generated. Therefore, the substantial electromagnetic conversion region as the head is the width l _{2 of} the second magnetic layer 7.
However, there is a problem that the track width is expanded to the width l ₁ of the first magnetic layer 3 although it is determined by the above, and it becomes difficult to narrow the track.

Further, in manufacturing, in this type of thin film magnetic head, in order to secure a predetermined electromagnetic conversion characteristic, the width l ₁ of the _first magnetic layer 3 in the track width direction and the width l ₁ of the second magnetic layer 7 in the track width direction are Set the width l ₂ to the specified value, and then set the clearance between the two.
Since it is necessary to keep d ₁ and d ₂ at extremely small predetermined values, pattern formation of the first magnetic layer 3 and the second magnetic layer 7 becomes extremely difficult.

Moreover, due to the positional deviation of the photomask when the second magnetic layer 7 is formed, the fluctuation of the pitch accuracy, and the like, the positional deviation between the first magnetic layer 3 and the second magnetic layer 7 in the track width direction is caused. Therefore, it is extremely difficult to keep the clearances d ₁ and d ₂ at predetermined values.

Further, since it is necessary to set the clearances d ₁ and d ₂ to minute dimensions, as shown in FIG. 8, in a general process of simultaneously forming a large number of magnetic head elements A on the same substrate 1. , Due to the positional deviation of the photomask when the second magnetic layer 7 is formed, the fluctuation of the pitch accuracy, and the like, the second magnetic layer 7 is changed to the first magnetic layer 3 as shown by the dotted line in FIG. There is also a problem that the risk of slipping to the outside is high, the product becomes defective, and the yield decreases.

As means for solving the above-mentioned problems, JP-A-60-133516
In the publication, the first magnetic layer and the second magnetic layer are trimmed by collective ion milling so that the first magnetic layer and the second magnetic layer have substantially the same width. The technology is disclosed.

However, in this conventional technique, both the magnetic layers of the first magnetic layer and the second magnetic layer are trimmed to have substantially the same width by collective ion milling.
When the positional deviation between the first magnetic layer and the second magnetic layer is large and the overlapping width of the two is small, a predetermined track direction width may not be obtained. There is also a problem that the widths of both magnetic layers are easily changed by the influence of the ion milling process.

Therefore, an object of the present invention is to solve the problems of the above-described conventional technique, to substantially reduce the electromagnetic conversion region in the track width direction, to correspond to a narrower track, and to improve the recording density. To provide a head and a manufacturing method suitable for manufacturing the thin film magnetic head.

<Means for Solving the Problems> In order to solve the above problems, the present invention provides a first substrate on a substrate.
A magnetic layer, a magnetic gap layer, a conductor coil, an insulating layer, and a second magnetic layer are laminated, and one ends of the first magnetic layer and the second magnetic layer are opposed to each other via a magnetic gap, The second magnetic layer is arranged in the surface of the first magnetic layer such that the portion forming the magnetic gap has a width smaller than the width of the first magnetic layer in the track width direction. The first magnetic layer has inclined surfaces that are downwardly inclined from the magnetic gap side toward the substrate at corners of both ends in the track width direction. Is formed by partially cutting out the corner portion of the second magnetic layer, starting from a position corresponding to the end position of the second magnetic layer, and ending in the middle of the thickness of the first magnetic layer. It is characterized by being

In addition, the manufacturing method according to the present invention for manufacturing the above-mentioned thin film magnetic head is performed after stacking a first magnetic layer, a magnetic gap layer, a conductor coil, an insulating layer and a second magnetic layer on a substrate. And a step of performing ion milling using a mask on the surface of the second magnetic layer or using the second magnetic layer as a mask, in the ion milling step, in the track width direction of the first magnetic layer. It is characterized in that corners at both ends are provided with an inclined surface which is directed from the magnetic gap side toward the substrate and which is inclined downward from a position corresponding to an end position of the second magnetic layer.

<Operation> The first magnetic layer has a slope inclined downward from the magnetic gap side toward the substrate at the corners at both ends in the track width direction on the one end side facing the second magnetic layer through the magnetic gap. Since it has a surface, magnetic pole reversal does not occur on the medium surface facing the inclined surface in the magnetic recording operation on the medium. Therefore, the substantial electromagnetic conversion area as the head is reduced to the width excluding the inclined surface portion. Therefore, the track width can be narrowed by the amount of the inclined surface, and the narrowed track can be achieved.

In the second magnetic layer, the portion forming the magnetic gap has a width smaller than the width of the first magnetic layer in the track width direction,
The first magnetic layer is arranged in the plane of the first magnetic layer, and the inclined surface of the first magnetic layer is inclined from the position corresponding to the end position of the second magnetic layer. The electromagnetic conversion regions of the second magnetic layer overlap with each other, and the substantial track width is reduced to the width of the second magnetic layer, and the width is accurately determined.

Since the inclined surface is formed by cutting out the corner of the first magnetic layer only partially so as to be limited to the corner, the first magnetic layer is formed by an ordinary method and then the corner is removed. ,
It is possible to form a highly accurate inclined surface according to the removal processing accuracy. Therefore, a thin film magnetic head having a highly accurate track width can be easily and surely obtained.

Moreover, since the inclined surface starts at a position corresponding to the end position of the second magnetic layer and ends midway in the thickness of the first magnetic layer, the thickness of the first magnetic layer is set to the magnetic saturation. It can be kept at a thickness that does not cause Therefore, the electromagnetic conversion efficiency does not decrease.

In obtaining the above-mentioned thin film magnetic head, the first
Magnetic layer, magnetic gap layer, conductor coil, insulating layer and second magnetic layer are laminated, and then a mask is applied to the surface of the second magnetic layer, or the second magnetic layer is used as a mask.
Perform ion milling. In the ion milling step, both ends of the magnetic gap layer and the first magnetic layer in the track width direction, which are stacked under the second magnetic layer and have a width corresponding to the width of the mask, are reduced by the ion milling.
Inclined surfaces that are inclined downward from the magnetic gap side toward the substrate are provided at both corners in the track width direction of the first magnetic layer.

The ion milling in the track width direction with respect to the first magnetic layer is determined by the mask width of the second magnetic layer or the mask width provided thereon. Therefore, a positional deviation in the track width direction occurs between the first magnetic layer and the second magnetic layer due to positional deviation of the photomask when forming the second magnetic layer, fluctuations in pitch accuracy, and the like. Also, the positional deviation can be absorbed by ion milling.

Moreover, since the first magnetic layer is ion-milled with the mask width, the dimensional difference between the first magnetic layer and the second magnetic layer in the track width direction is set large, and the difference is deleted by ion milling to obtain the first magnetic layer. The width of the magnetic layer can be matched with the width of the second magnetic layer. Therefore, the formation of the first magnetic layer and the second magnetic layer is facilitated, the generation of defective products is suppressed, and the yield is improved.

Further, since the dimensional difference between the first magnetic layer and the second magnetic layer in the track width direction can be increased, the second magnetic layer can be formed in the general process of simultaneously forming a large number of magnetic head elements on the same substrate. Even if the photomask is misaligned when a layer is formed, the pitch accuracy is changed, or the like, this can be absorbed by ion milling, the generation of defective products can be suppressed, and the yield can be improved.

<Example> FIG. 1 is a front view of a part of a thin film magnetic head according to the present invention. In the figure, the same reference numerals as those in FIGS. 6 and 7 denote the same components. The first magnetic layer 3 has magnetic gaps G ₁ at the corners at both ends in the track width direction on the one end side facing the second magnetic layer 7 via the magnetic gap G _1.
The inclined surfaces 31 and 32 are inclined downward at an angle θ from the side toward the substrate 1. FIG. 2 is a perspective view showing the shape of the inclined surfaces 31 and 32. The inclined surfaces 31 and 32 are located at the corners at both ends in the track width direction on the one end side facing the second magnetic layer 7 and on the magnetic gap G ₁ side. Has a shape that is obliquely cut out toward the substrate 1 (see FIG. 1).

When magnetic recording is performed on the medium using the thin film magnetic head, magnetic pole reversal does not occur on the medium surface facing the inclined surfaces 31 and 32. Therefore, the substantial electromagnetic conversion area as the head is reduced to the width excluding the inclined surfaces 31 and 32. Therefore, the track width on the medium can be narrowed by the amount of the inclined surfaces 31 and 32, and the narrowed track can be achieved.

The inclined surfaces 31 and 32 are formed so as to start immediately below both end edges of the second magnetic layer 7 in the track width direction, and the magnetic gap layer 3 is formed.
The surface 33 of the first magnetic layer 3 and the surface 73 of the second magnetic layer 7 which are opposed to each other with the same width l ₂ overlap each other. By doing so, the electromagnetic conversion regions of the first magnetic layer 3 and the second magnetic layer 7 overlap each other, and the substantial track width is the width of the second magnetic layer 7.
together is reduced to l _2, it is accurately determined by the width l _2. Moreover, the electromagnetic conversion efficiency does not decrease. Inclined surface 31, 32
The shape of is not limited to the plane shown in the figure, but may be formed in a curved shape.

Next, regarding the method of manufacturing the thin film magnetic head according to the present invention,
This will be described with reference to FIG. First, Fig. 3 (a ₁ ),
As shown in (b ₁ ), the underlayer 2, the first magnetic layer 3, the magnetic gap layer 4, the conductor coil 5, the insulating layer 6, and the second magnetic layer 7 are formed on the substrate 1 according to a normal process. Are formed by stacking.

Next, as shown in FIGS. 3 (a ₂ ) and 3 (b ₂ ), a mask 9 is applied to the surface of the second magnetic layer 7. The mask 9 is preferably formed so that the width l ₃ in the track width direction is narrower than the width l _{2 of} the second magnetic layer 7. Even if the formation position of the mask 9 with respect to the second magnetic layer 7 deviates, the mask 9 does not protrude from the second magnetic layer 7 as long as the position deviation is within the width difference, and a predetermined width l ₃ can be secured. Because. The mask 9 can be formed of, for example, a rubber negative photoresist, a novolac resin positive photoresist, or the like. In the embodiment, the mask 9 is formed on the entire surface of the second magnetic layer 7.

Next, ion milling is applied to the vicinity of the end 10 from above the mask 9. Due to this ion milling, both ends of the first magnetic layer 3, the magnetic gap layer 4, and the second magnetic layer 7 located outside the width l ₃ of the mask 9 in the track width direction,
It is deleted as shown in Fig. 3 (a ₃ ) and (b ₃ ). Ar gas ions accompanying ion milling come from a direction perpendicular to the surfaces of the second magnetic layer 7, the magnetic gap layer 4, and the first magnetic layer 3, but the end portion of the mask 9 in the track width direction. Since the Ar gas ions acting on the inner side and the outer side are quantitatively different, the second magnetic layer 7, the magnetic gap layer 4, and the first magnetic layer 3 are inclined downward toward the substrate 1. As is done, it is deleted diagonally. Therefore, after the second magnetic layer 7 and the magnetic gap layer 4 are removed, the corners of both ends of the first magnetic layer 3 at the bottom in the track width direction are located in the direction of the substrate 1 from the magnetic gap side. Inclined surfaces 31 and 32 are formed so as to descend downward. The depths, angles, etc. of the inclined surfaces 31, 32 can be set to desired values by controlling the ion milling time and the like.

In the case of ion milling, since Ar gas ions are used,
Unlike dry etching or the like, it is not removed inside the mask 9. Therefore, the width of the magnetic gap layer 4 and the second magnetic layer 7 in the track width direction is equal to the width of the mask 9.
Can be set to a value approximately equal to l ₃ .

As described above, the ion milling in the track width direction with respect to the first magnetic layer 3 and the second magnetic layer 7 is determined by the width l _{3 of the} mask 9 provided on the second magnetic layer 7. Therefore, as shown in FIG. 4, the first magnetic layer 3 and the second magnetic layer 7 are separated from each other due to the positional deviation of the photomask when the second magnetic layer 7 is formed, the fluctuation of the pitch accuracy, and the like. Even if there is a positional deviation Δl in the track width direction, the width l _{3 of the} mask 9
Then, since ion milling is performed as shown by the dotted line, the positional deviation Δl can be absorbed. The same applies when a positional deviation occurs between the second magnetic layer 7 and the mask 9.

Moreover, since ion milling of the first magnetic layer 3 is performed with the mask width l ₃ , the dimensional difference Δd (see FIG. 4) in the track width direction between the first magnetic layer 3 and the second magnetic layer 7 is increased. In particular, the dimension difference Δd can be absorbed by ion milling to match the width of the first magnetic layer 3 with the width of the second magnetic layer 7. Therefore, the formation of the first magnetic layer 3 and the second magnetic layer 7 is facilitated, the generation of defective products is suppressed, and the yield is improved. The same applies when the step of simultaneously forming a large number of magnetic head elements on the same substrate is taken.

FIG. 5 is a view showing another embodiment of the mask 9, in which a first mask layer 91 made of alumina is formed on the second magnetic layer 7.
A second mask layer 92 made of a rubber-based negative photoresist, a novolac resin-based positive photoresist or the like is laminated on the first mask layer 91 to form a multilayer structure.

The mask 9 needs to be removed after the ion milling process is completed. However, as described above, the mask 9 needs to be formed of a rubber negative photoresist, a novolac resin positive photoresist, or the like, which has a strong adhesion to the second magnetic layer 7 and is difficult to remove. Particularly, peeling becomes difficult when it is formed by a high-resolution novolac resin-based positive photoresist.

On the other hand, as shown in FIG. 5, a first mask layer 91 made of alumina is formed on the second magnetic layer 7, and a rubber-based negative type photo resist is formed on the first mask layer 91. With the structure in which the second mask layer 92 made of a resist, a novolac resin-based positive photoresist, or the like is laminated, the second magnetic layer 7, the magnetic gap layer 4, and the first magnetic layer 3 are formed in the ion milling process. Simultaneously with the ion milling, most of the second mask layer 92 can be removed by the ion milling, and the ion milling process can be performed so that the first mask layer 91 is exposed. In this case, the first mask layer 91 remains on the surface of the second magnetic layer 7, and the first mask layer 91 is the same alumina as the insulating protective film (see FIG. 6) laminated thereafter. Therefore, it does not need to be removed. Therefore, the mask peeling work is unnecessary, and the manufacturing efficiency is improved. Moreover, since the remaining first mask layer 91 serves as a protective layer for the second magnetic layer 7, the surface of the second magnetic layer 7 is not damaged by ion milling.

<Effects of the Invention> As described above, according to the present invention, the following effects can be obtained.

(A) A first magnetic layer, a magnetic gap layer, a conductor coil, an insulating layer, and a second magnetic layer are laminated on a substrate, and one end of the first magnetic layer and the second magnetic layer is provided with a magnetic gap. In the thin film magnetic head opposed to each other with the inclined surface inclined downward from the magnetic gap side toward the substrate at the corners of both ends in the track width direction of the first magnetic layer, the electromagnetic force in the track width direction is reduced. It is possible to provide a thin film magnetic head in which the conversion region is substantially reduced to cope with a narrow track and the recording density can be improved.

(B) The second magnetic layer is arranged in the plane of the first magnetic layer such that the portion forming the magnetic gap has a width smaller than the width of the first magnetic layer in the track width direction. Since the inclined surface of the first magnetic layer is inclined from the position corresponding to the end position of the second magnetic layer, the track width of the second magnetic layer is substantially reduced without decreasing the electromagnetic conversion efficiency. It is possible to provide a thin film magnetic head set to an exact size determined by the width of the layer. Further, since the inclined surface is formed by partially cutting out the corner of the first magnetic layer and limited to the corner, it is possible to easily and surely obtain a thin film magnetic head having a highly accurate track width. it can.

Moreover, since the inclined surface starts from the position corresponding to the end position of the second magnetic layer and ends in the middle of the thickness of the first magnetic layer, the electromagnetic conversion efficiency does not decrease.

(C) A method of manufacturing a thin film magnetic head according to the present invention comprises a first magnetic layer, a magnetic gap layer, a conductor coil, and
After stacking the insulating layer and the second magnetic layer, a step of performing masking on the surface of the second magnetic layer, or performing ion milling using the second magnetic layer as a mask, The first magnetic layer is provided at its corners at both ends in the track width direction with inclined surfaces extending from the magnetic gap side toward the substrate and further downwardly inclined from the position corresponding to the end position of the second magnetic layer. Since the,
The thin film magnetic head according to the present invention can be obtained.

(D) In the manufacturing process, even if a positional deviation in the track width direction occurs between the first magnetic layer and the second magnetic layer, the positional deviation can be absorbed by ion milling.

(E) In the manufacturing process, a large clearance in the track width direction between the first magnetic layer and the second magnetic layer is set,
The clearance can be absorbed by ion milling to match the width of the first magnetic layer with the width of the second magnetic layer. Therefore, the formation of the first magnetic layer and the second magnetic layer is facilitated, the generation of defective products is suppressed, and the yield is improved.

[Brief description of drawings]

FIG. 1 is a front view of a part of a thin film magnetic head according to the present invention,
FIG. 2 is a perspective view showing a main part configuration of the first magnetic layer and the second magnetic layer according to the present invention, FIG. 3 _{(a 1) ~ (a 3} ) the production of thin-film magnetic head according to the present invention Sectional views showing the steps, and FIGS. 3 (b ₁ ) to (b ₃ ) are views similarly seen from the medium sliding contact side, FIG.
FIG. 5 is a diagram for explaining the ion milling action in the method of manufacturing a thin film magnetic head according to the present invention, FIG. 5 is a sectional view showing another embodiment of a mask, FIG. 6 is a sectional view of a conventional thin film magnetic head, and FIG. FIG. 7 is a partial front view and FIG. 8 is a view for explaining the problem. 1 ... Substrate, 3 ... First magnetic layer 4 ... Magnetic gap layer, 5 ... Conductor coil 7 ... Second magnetic layer, 9 ... Mask 31, 32 ... Inclined surface

Claims (2)

[Claims] 1. A first magnetic layer, a magnetic gap layer, a conductor coil, an insulating layer, and a second magnetic layer are laminated on a substrate, and one ends of the first magnetic layer and the second magnetic layer are magnetic. In the thin film magnetic head opposed to each other via a gap, the second magnetic layer has a portion forming the magnetic gap having a width smaller than a width of the first magnetic layer in a track width direction, The first magnetic layer is disposed in a plane of the first magnetic layer, and the first magnetic layer has inclined surfaces at the corners at both ends in the track width direction that are inclined downward from the magnetic gap side toward the substrate. From the position corresponding to the end position of the second magnetic layer, the inclined surface is formed only in the corner by partially cutting out the corner of the first magnetic layer. Characterized in that it starts and ends in the middle of the thickness of the first magnetic layer. Thin film magnetic head. 2. A method of manufacturing a thin film magnetic head, comprising laminating a first magnetic layer, a magnetic gap layer, a conductor coil, an insulating layer and a second magnetic layer on a substrate, wherein One ends of the first magnetic layer and the second magnetic layer are opposed to each other via the magnetic gap layer, and in the second magnetic layer, a portion forming the magnetic gap layer is a track of the first magnetic layer. A layer having a width smaller than the width in the width direction is stacked in the plane of the first magnetic layer, and then the surface of the second magnetic layer is masked or the second magnetic layer is formed. By performing ion milling using the as a mask, only the corners of both ends of the first magnetic layer in the track width direction,
A method for manufacturing a thin-film magnetic head, comprising forming an inclined surface starting from a position corresponding to an end position of the second magnetic layer and ending in the middle of the thickness of the first magnetic layer.