JP2950246B2 - Composite type thin film magnetic head - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a composite thin-film magnetic head, and more particularly to a composite thin-film magnetic head having a reproducing head using a magnetoresistive effect and an inductive recording head to reduce Barkhausen noise. It concerns the head.

[0002]

2. Description of the Related Art In recent years, there has been a remarkable increase in the recording capacity of a magnetic disk drive. This increase in recording capacity is mainly due to an increase in magnetic recording density.
In general, as the magnetic recording density increases, the signal output reproduced by the magnetic head decreases. In order to improve this, a magnetoresistive read magnetic head has come to be put to practical use as an alternative to the conventional inductive read magnetic head.

In order to perform magnetic recording, a magnetic head provided with an inductive magnetic head adjacent to the magnetoresistive read head is used. A recording / reproducing head having such a structure is referred to as a magnetoresistive / inductive combined thin film magnetic head. Hereinafter, for simplicity, it is referred to as a composite thin-film magnetic head (or MR composite head).

The magnetoresistive read head described above is generally composed of a pattern formed of a thin film exhibiting a magnetoresistive effect, such as NiFe, as a magnetoresistive magneto-sensitive element, and the pattern thereof. Magnetic field applying means for obtaining the linearity of the response of the resistance value to the applied magnetic field. The bias magnetic field applying means may be a soft film bias means for magnetizing a soft magnetic thin film adjacent to the magnetoresistive effect magnetic element with a sense current and using a magnetic field generated from the magnetization, or a magnetic sensitive element at the center of the magnetic shield gap. Asymmetric shield bias means utilizing a magnetic field resulting from the asymmetry of the sense current mirror image effect by deviating,
Generally well known.

FIG. 5 shows a conventional example of an MR composite head having this asymmetric shield bias means. In the conventional example shown in FIG. 5, a first shield pattern 101 as a magnetic shield and a first insulating layer 1 are arranged from below to above in FIG.
02, magneto-sensitive element (magnetoresistive magneto-sensitive element) 103, second
An insulating layer 104 and a second shield pattern 105 functioning as a magnetic shield are sequentially laminated. Furthermore,
A recording gap layer 106, an exciting coil 107 and a recording yoke pattern 108 are sequentially laminated.

Here, the thickness of the first insulating layer 102 is
The thickness of the insulating layer 104 is smaller than the thickness of the insulating layer 104, whereby the magneto-sensitive element 103 is disposed closer to the first shield pattern 101 than the center of the shield pattern gap.

When the sense current is applied to the magneto-sensitive element 103, the relationship between the magnetic field generated from the mirror image of the sense current generated by the magnetic shield and the magneto-sensitive element 103 is analyzed, and the mirror image of the first shield pattern 101 is obtained. Since the magnetic field is close to the magnetic sensing element 103, the magnetic field applied to the magnetic sensing element 103 is stronger than the magnetic field from the second shield pattern 105. As a result, a bias magnetic field is applied to the magnetic sensing element 103. Becomes

In the reproducing operation of such a magnetoresistive reproducing head, a fluctuation phenomenon of the reproduction output due to Barkhausen noise related to the magnetic domain hard structure of the magneto-sensitive element 103 is often observed. To solve this problem, Japanese Patent Application Laid-Open No. 63-9 / 1988
Japanese Patent No. 6714 discloses a technique for controlling the direction of magnetic anisotropy of a magneto-sensitive element.

[0009]

However, when a recording head is arranged in the vicinity like an MR compound head,
The control of the magnetic anisotropy of the magneto-sensitive element alone was not sufficient for controlling the fluctuation of the reproduction output. Further, when such a magnetic head is mounted, data errors of the magnetic disk device increase. Then, depending on the degree of fluctuation of the reproduction output, a malfunction of the apparatus occurs. It is generally understood that such a phenomenon is caused by Barkhausen noise caused by an irregular change in the magnetic domain structure such as a magnetoresistive effect magnetic sensing element and a magnetic shield material which are constituent materials of the head.

Also, in the MR composite head, as in the case of the conventional inductive head, there is a problem in that the output fluctuation is small only by the reproducing operation, and the reproducing output is likely to fluctuate when the recording operation is performed.

Further, in the conventional asymmetric shield type MR composite head, when the recording operation is performed, the first shield pattern 101 is very close to the second shield pattern 105 via the insulating layer. As shown in (2), it is strongly magnetized similarly to the second shield pattern 105. Here, the arrows indicate the flow of magnetism. For this reason, a strong magnetic field is also applied to the magnetoresistive effect magnetic sensing element 103 arranged near the first shield pattern 101,
The magnetic domain structure of the magneto-sensitive element 53 changes. When the magnetic domain structure of the magneto-sensitive element 53 changes, the resistance value of the magneto-sensitive element 53 fluctuates, which causes a problem that the reproduction output fluctuates.

The magnetic domain structure of the first shield pattern 51 itself also changes during recording, so that the mirror image effect changes, and the bias magnetic field applied to the magnetoresistive magneto-sensitive element 53 also changes. This change in the bias magnetic field changes the reproduction sensitivity of the magneto-sensitive element 53, and the reproduction output also fluctuates at this point.

[0013]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a composite thin-film magnetic head which can improve the disadvantages of the prior art, and in particular, reduce fluctuations in the reproduction output and thereby operate stably and with high reliability. Aim.

[0014]

To achieve the above object, according to the first aspect of the present invention, a first shield pattern, a first insulating layer, and a magnetoresistive magnetoresistive type for reproduction are provided on a substrate member. An element, a second insulating layer, and a second shield pattern are sequentially stacked. Further, a magnetoresistive read head is formed by the magnetoresistive magneto-sensitive element and the first insulating layer and the second insulating layer laminated with the magneto-resistive magnetic sensing element interposed therebetween. Further, a recording yoke pattern is disposed on the second seal pattern via a magnetic recording gap layer, and an exciting coil is provided between the recording yoke pattern and the second seal pattern to form a recording head portion. Then, the gap between the first shield pattern and the second shield pattern is increased by the magnetoresistance effect at the recording medium facing portion.
Except for the mold magnetically sensitive element portion is set larger than the gap of the magnetoresistive sensing element portion. In addition, the first
In the gap between the shield pattern and the second shield pattern , the magnetoresistive effect type
The configuration is such that a non-magnetic insulating layer is embedded except for the magneto-sensitive element portion .

For this reason, in the invention according to claim 1,
During the recording operation, first, the yoke pattern and the second shield pattern are strongly magnetized by the current magnetic field generated from the exciting coil. In this case, the first shield pattern is hardly magnetized because most of the first shield pattern is sufficiently separated from the second shield pattern. Therefore, even if the magneto-sensitive element is close to the first shield pattern, the magneto-sensitive element is less likely to receive an unnecessary magnetic field. Further, since it is relatively far away from the strongly shielded second shield pattern, the unnecessary magnetic field applied to the magneto-sensitive element can be small.
Further, the unnecessary magnetic field at the time of recording received by the magnetoresistive effect type magnetic sensing element portion is further reduced by the action of the nonmagnetic insulating layer, so that the reproduction output is further stabilized.

That is, the unnecessary magnetic field at the time of recording received by the magnetoresistive effect type magnetic sensing element is greatly reduced. Therefore, the change of the magnetic domain state of the magneto-sensitive element after the recording operation is small, and the fluctuation of the reproduction output by the magneto-sensitive element is significantly smaller than that of the conventional one.

According to the second aspect of the present invention, similarly to the first aspect of the present invention, first, the first member is placed on the substrate member.
, A first insulating layer, a magnetoresistive magneto-sensitive element for reproduction, a second insulating layer, and a second shield pattern are sequentially laminated. In addition, the magnetoresistive effect type magnetic sensing element and the first insulating layer and the second insulating layer laminated with the magnetoresistive effect type magnetic sensing element interposed therebetween form a magnetoresistive effect reproducing head. Furthermore, a recording yoke pattern is arranged on the second seal pattern via a magnetic recording gap layer, and an exciting coil is provided between the recording yoke pattern and the second seal pattern to form a recording head portion. Then, a gap between the first shield pattern and the second shield pattern is provided in the recording medium facing portion.
Except for a certain magneto-resistance effect type magnetic sensing element portion, the gap is set to be larger than the gap of the magneto-resistance effect type magnetic sensing element portion. Further, the first in the magnetoresistive effect type reproducing head described above
Is an asymmetrical shield type magnetoresistive effect reproducing head portion which is set thinner than the second insulating layer, and a gap between the first shield pattern and the second shield pattern, The magnetic resistor in the recording medium facing section described above
The configuration is such that a nonmagnetic insulating layer is embedded except for the anti-effect type magnetic sensing element .

Therefore, in the invention according to claim 2,
2. The case according to claim 1, wherein the magnetoresistive effect type magnetic sensing element of the magnetoresistive effect reproducing head is further away from the exciting coil, and the unnecessary magnetic field received by the magnetosensitive element during recording is as described above. Therefore, the reproduction output is more stable than in the case of the first aspect.

According to a third aspect of the present invention, in the composite thin-film magnetic head according to the first or second aspect, the second shield pattern is formed in a planar shape and the first shield pattern is recorded. Magnetoresistance in the medium facing part
Except for the effect-type magnetic sensing element portion , a configuration is adopted in which it is formed in a partially bent state away from the second shield pattern.

Therefore, in the invention according to claim 3,
In addition to functioning in the same manner as in the first or second aspect of the present invention, the effect of an unnecessary magnetic field at the time of recording on the magnetoresistive effect type magnetic sensing element can be reduced more reliably, and a stable reproduction output Can be obtained.

According to a fourth aspect of the present invention, in the composite thin film magnetic head according to the first or second aspect, the first shield pattern is formed in a planar shape, and the second shield pattern is formed by the recording method. Magnetoresistance in the medium facing part
Except for the effect type magnetic sensing element portion , the configuration is such that it is formed in a partially bent state away from the first shield pattern.

[0022] Even in such a case, the fourth aspect of the invention can provide the same function as that of the third aspect of the invention.

[0023]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS (First Embodiment) A first embodiment of the present invention will be described below with reference to FIG. In FIG. 1, reference numeral 100 denotes a substrate member. On the substrate member 100, a first shield pattern 1 made of a soft magnetic shield pattern and a first insulating layer 2
And a magnetoresistive element for reproduction (hereinafter referred to as a “magnetic element”) 3, a second insulating layer 4, and a second shield pattern 5 composed of a soft magnetic shield pattern. ing.

In this case, the first insulating layer 2 laminated via the magnetic sensing element 3 is set thinner than the second insulating layer 4 to form an asymmetric shield type magnetoresistive read head. I have. A recording yoke pattern 8 is disposed on the second seal pattern 5 with a magnetic recording gap 6 interposed therebetween, and a gap insulating layer 7A and an exciting portion are provided between the recording yoke pattern 8 and the second seal pattern 5 described above. By providing the coil pattern 7, a recording head section is formed.

Then, the above-described first shield pattern 1
When the gap between the second shield pattern 5, the above-described serial
Except for the magnetic sensing element 3 in the recording medium facing portion, the gap is set to be larger than the gap between the magnetic sensing elements 3.

More specifically, the gap between the first shield pattern 1 and the second shield pattern 5 is as follows.
In the embodiment shown in FIG. 1, the first shield pattern 1 or the second shield pattern 5 is formed to be larger than the thickness, but the present invention is not necessarily limited to this. Furthermore, the first shield pattern 1 and the second shield pattern 1
A flat buried region 11 is provided in a portion where the gap with the shield pattern 5 is widened, and a non-magnetic insulating layer (non-magnetic and electrically insulating layer) made of a non-magnetic material is provided in the flat buried region 11 as a flat buried layer. ) 11A is embedded.

Further, the magneto- sensitive device in the recording medium facing portion described above
Between the first shield pattern 1 and the substrate member 100 in the element 3, an insulating member (non-magnetic and electrically insulating member) made of a material equivalent to the magneto-sensitive element 3 or a non-magnetic member is embedded. A convex region 100A is provided. The height of the convex region 100A is set to be substantially the same as the thickness of the second shield pattern 5 described above.

Next, the forming process, the recording operation, and the like of the first embodiment will be described. In the first embodiment, before forming the first shield pattern 1, first, the substrate material 100 is dug to replace the above-described magneto-sensitive element portion with the convex region 100.
The operation of leaving as A is performed. The height of the convex region 100A is substantially equal to the thickness of the second shield pattern 5 as described above. Next, a first shield pattern 1 is formed, a non-magnetic insulating member having a thickness equal to or greater than the thickness of the convex region 100A is applied, and planarization is performed by a plane wrap or etch-back method to form a non-magnetic insulating layer (flattening embedded). Layer) 11A is formed. Next, the first insulating layer 2, the magneto-sensitive element 3, the second insulating layer 4, the second shield pattern 5, the recording gap 6,
The gap insulating layer 7A and the exciting coil pattern 7 are formed.

During a recording operation, a current pulse is applied to the exciting coil pattern 7. Then, first, the recording yoke pattern 8 and the second shield pattern 5 are strongly magnetized by the current magnetic field generated from the exciting coil pattern 7. in this case,
In the present embodiment, the first shield pattern 1 is hardly magnetized because most of the first shield pattern 1 is sufficiently separated from the second shield pattern 5. Therefore, even when the magneto-sensitive element 3 is close to the first shield pattern 1, it is less likely to receive an unnecessary magnetic field. Further, since it is relatively far from the strongly shielded second shield pattern 5, the unnecessary magnetic field applied to the magneto-sensitive element 3 can be small.

That is, the unnecessary magnetic field at the time of recording received by the magneto-sensitive element 3 is greatly reduced by applying this embodiment. Therefore, the change of the magnetic domain state of the magneto-sensitive element 3 after the recording operation is small, and the fluctuation of the reproduction output by the magneto-sensitive element 3 is extremely small as compared with the conventional one.

Here, in the first embodiment,
The case where the nonmagnetic insulating layer (flattening buried layer) 11A is provided between the first shield pattern 1 and the second shield pattern 5 is exemplified. Alternatively, the above-described first insulating layer 2 may be used by thickening the corresponding portion.

(Second Embodiment) Next, a second embodiment of the present invention will be described with reference to FIG. Here, the same reference numerals are used for the same components as those in the embodiment of FIG. 1 described above. Second embodiment shown in FIG. 2, unlike in the case of the embodiment of FIG. 1 described above, to form a first shield pattern 21 in a planar shape, the second shield pattern 25, a recording medium facing
Except for the magneto-sensitive element 23 in the portion , a feature is that it is formed in a partially bent state away from the first shield pattern 21.

In the portion where the gap between the first shield pattern 21 and the second shield pattern 25 is widened (except for the magneto-sensitive element 23), a non-magnetic insulating layer (non-magnetic A magnetic and electrical insulating layer) 23A is provided. The nonmagnetic insulating layer (projection layer) 23A is set in a state sandwiched between the first insulating layer 22 and the second insulating layer 24. Other configurations are the same as those of the above-described embodiment of FIG.

In the embodiment shown in FIG. 2, the first
The method for forming the interlayer gap between the shield pattern 21 and the second shield pattern 25 is different from the above-described embodiment of FIG. That is, first, the first shield pattern 21 is formed on the flat substrate member 100. The method of formation is based on the usual magnetic film formation, photoresist coating, exposure, and milling.

Next, a first insulating layer 22 and a magnetic sensing element 23 are sequentially formed. Subsequently, a non-magnetic insulating layer 23A as a convex layer for increasing the shield gap is formed on the right side of the recording medium facing region of the magneto-sensitive element 3 in FIG. The thickness of the nonmagnetic insulating layer (projection layer) 23A is set to be substantially equal to the thickness of the second shield pattern 25.

Next, a second insulating layer 24 and a second magnetic shield pattern 25 are sequentially formed. Then, the recording gap 26, the exciting coil 27, and the recording yoke pattern 28 are sequentially formed in the same manner as in the case of FIG. Even in this case, the same operational effects as those of the embodiment shown in FIG. 1 described above can be obtained for the magnetic domain stability after the recording operation.

Here, in the first embodiment,
First shield pattern 21 and second shield pattern 25
A non-magnetic insulating layer 23A as a convex layer is provided between the first and second layers. However, instead of the non-magnetic insulating layer (convex layer) 23A, the above-described second insulating layer 24 is thickened at the corresponding portion. You may use it.

(Third Embodiment) Next, a third embodiment of the present invention will be described with reference to FIG. Here, the same reference numerals are used for the same components as those in the embodiment of FIG. 1 described above.

In the third embodiment, the stacking order of each pattern is reversed as compared with the first embodiment in FIG. That is, first, a recording yoke pattern 38 is formed on the substrate member 100, and then a gap insulating layer 37A having a recording gap 36 at one end is formed, and the exciting coil 37 is embedded in the gap insulating layer 37A. Then, a second shield pattern 35 is formed thereon.

Further, the second magnetic shield pattern 35
A second insulating layer 34, a magneto-sensitive element 33, a first insulating layer 32, and a first shield pattern 31 are sequentially stacked thereon. Here, the thickness of the first insulating layer 32 is the same as that of the above-described first embodiment (in the case of FIG. 1).
4 is formed to be smaller than the thickness. Other configurations are the same as those of the first embodiment (FIG. 1).

In this case, the same operation and effect as those of the first embodiment (in the case of FIG. 1) can be obtained.

(Fourth Embodiment) Next, a fourth embodiment of the present invention will be described with reference to FIG. Here, the same reference numerals are used for the same components as those in the embodiment of FIG. 1 described above.

The fourth embodiment is different from the first embodiment in that the magneto-sensitive element 3 is different from the first shield pattern 1 in the first embodiment.
The magnetic sensing element 43 is arranged at a position intermediate between the first shield pattern 41 and the second shield pattern 45 (see FIG. 1). It is characterized by the fact that it is set up. The bias magnetic field is applied to the magneto-sensitive element 43 by a soft film bias method including a soft magnetic film adjacent to the magneto-sensitive element 43. Other configurations are the same as those of the embodiment of FIG. 1 described above.

Even in this case, the influence of the magnetization on the first shield pattern 41 during the recording operation is greatly reduced as in the case of the above-described first embodiment. The unnecessary magnetic field is greatly reduced as compared with the conventional one, and the change in the reproduction output after recording is reduced as compared with the conventional one.

As described above, also in the fourth embodiment, it is possible to obtain substantially the same operation and effect as those of the first embodiment (in the case of FIG. 1).

[0046]

Since the present invention is constructed and functions as described above, according to this, the magnetic field generated during the recording operation is the second magnetic field.
The degree of leakage from the shield pattern of the first shield pattern to the first shield pattern is greatly reduced, so that an unnecessary magnetic field applied to the magneto-sensitive element surrounded by the second shield pattern and the first shield pattern is smaller than that of the conventional shield pattern. Therefore, the change of the magnetic domain state with respect to the magneto-sensitive element at the time of the recording operation, which has conventionally occurred, is small,
For this reason, the fluctuation of the reproduction output from the recording medium by the magneto-sensitive element is reduced, and in this respect, a highly reliable composite thin film magnetic head with stable operation can be provided.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating a first embodiment of the present invention.

FIG. 2 is a sectional view showing a second embodiment of the present invention.

FIG. 3 is a sectional view showing a third embodiment of the present invention.

FIG. 4 is a sectional view showing a fourth embodiment of the present invention.

FIG. 5 is a sectional view showing a conventional example.

FIG. 6 is an explanatory diagram showing a function of a shield pattern in FIG. 5;

[Description of Signs] 1,21,31,41 First shield pattern 2,22,32,42 First insulating layer 3,23,33,43 Magnetoresistance effect type magnetosensitive element (magnetic sensitive element) 4, 24, 34, 44 Second insulating layer 5, 25, 35, 45 Second shield pattern 6, 26, 36, 46 Recording gap 7, 27, 37, 47 Exciting coil pattern 8, 28, 38, 48 Recording yoke pattern 11A , 23A Nonmagnetic insulating layer 100 Substrate member

Claims (4)

(57) [Claims] A first shield pattern on a substrate member;
A first insulating layer, a magnetoresistive magneto-sensitive element for reproduction,
Are sequentially laminated, and the first insulating layer and the second insulating layer laminated via the magnetoresistive effect type magnetic sensing element and the magnetoresistive effect type magnetic sensing element To form a magnetoresistive read head, a recording yoke pattern is disposed on the second seal pattern via a magnetic recording gap layer, and an exciting coil is provided between the recording yoke pattern and the second seal pattern. In the composite type thin film magnetic head in which a recording head portion is formed by equipping the recording medium , the gap between the first shield pattern and the second shield pattern is formed by the magnetoresistive effect type magnetic sensing element in the recording medium facing portion.
Except for the element portion , the gap is set to be larger than the gap of the magnetoresistive effect type magnetic sensing element portion, and the gap between the first shield pattern and the second shield pattern is located at the recording medium facing portion. The magnetic resistor
A composite thin-film magnetic head characterized in that a non-magnetic insulating layer is buried except for an anti-effect type magnetic sensing element . 2. A first shield pattern on a substrate member.
A first insulating layer, a magnetoresistive magneto-sensitive element for reproduction,
Are sequentially laminated, and the first insulating layer and the second insulating layer laminated via the magnetoresistive effect type magnetic sensing element and the magnetoresistive effect type magnetic sensing element To form a magnetoresistive read head, a recording yoke pattern is disposed on the second seal pattern via a magnetic recording gap layer, and an exciting coil is provided between the recording yoke pattern and the second seal pattern. In the composite type thin film magnetic head in which a recording head portion is formed by equipping the recording medium , the gap between the first shield pattern and the second shield pattern is formed by the magnetoresistive effect type magnetic sensing element in the recording medium facing portion.
Except for the element portion , the gap is set to be larger than the gap between the magnetoresistive effect-type magneto-sensitive element portions , and the first magneto-resistive read head section is stacked via the magneto-resistive effect-type magneto-sensitive element. Second insulating layer
An asymmetric shield type magnetoresistive read head portion which is set to be thinner than the insulating layer of (a), wherein a gap between the first shield pattern and the second shield pattern is provided in a recording medium facing portion. Magnetic resistance
A composite thin-film magnetic head characterized in that a non-magnetic insulating layer is buried except for an anti-effect type magnetic sensing element . 3. The recording medium according to claim 2, wherein the second shield pattern is formed in a planar shape, and the first shield pattern is formed on a recording medium.
3. The device according to claim 1, wherein a part is bent away from the second shield pattern except for the magnetoresistive effect type magnetic sensing element in an opposing portion.
A composite thin-film magnetic head according to claim 1. 4. The recording medium according to claim 1, wherein the first shield pattern is formed in a planar shape, and the second shield pattern is formed on a recording medium.
3. The device according to claim 1, wherein a part is bent away from the first shield pattern except for a part of the magnetoresistive effect type magnetic sensing element in the facing part.
A composite thin-film magnetic head according to claim 1.