JP3474533B2 - Thin film magnetic head and method of manufacturing the same - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thin film magnetic head having at least an inductive type electromagnetic conversion element and a method for manufacturing the thin film magnetic head.

[0002]

2. Description of the Related Art In recent years, as the areal recording density of hard disk devices has increased, there has been a demand for improved performance of thin film magnetic heads. The thin film magnetic head has a structure in which a recording head having an inductive electromagnetic conversion element for writing and a reproducing head having a magnetoresistive element for reading (hereinafter also referred to as MR (Magneto-resistive) element) are laminated. Composite thin film magnetic heads are widely used.

The recording head is provided between the lower magnetic pole layer and the upper magnetic pole layer, which include magnetic pole portions facing each other on the air bearing surface side, and the magnetic pole portion of the lower magnetic pole layer and the magnetic pole portion of the upper magnetic pole layer. A gap layer and a thin film coil provided at least partially insulated from the lower magnetic pole layer and the upper magnetic pole layer are provided.

By the way, what is required of the recording head for increasing the recording density is, in particular, reduction of the magnetic pole width that defines the recording track width and improvement of the recording characteristics. For example, 3
In order to realize a thin film magnetic head having an areal recording density exceeding 0 gigabits / (inch) ² , a pole width of 0.4 μm or less is required. On the other hand, when the magnetic pole width becomes smaller, the recording characteristics deteriorate. For example, every time the magnetic pole width is reduced by 0.1 μm, the overwrite characteristic, which is a characteristic in the case of overwriting, is reduced by about 2 to 3 dB. Therefore, as the magnetic pole width becomes smaller, the recording characteristics need to be further improved.

As a method of forming a magnetic pole that defines the recording track width, for example, a frame plating method is used as disclosed in Japanese Patent Laid-Open No. 7-262519. In the frame plating method, a base film to be an electrode for plating is formed on the base by, for example, a sputtering method,
A resist layer is formed on the base film, and the resist layer is patterned by a photolithography process to form a frame (outer frame) for plating. Then, using this frame, plating is performed using the previously formed underlayer film as an electrode to form a plated layer serving as a magnetic pole on the underlayer film. After that, the frame is removed, and unnecessary portions of the base film other than the portion existing under the plating layer are removed by dry etching such as ion milling.

[0006]

By the way, a conventional undercoating film formed by sputtering is deteriorated in soft magnetic characteristics if it is too thin. For example, JP-A-5-73839.
It has been said that a thickness of about 0.1 μm or more is required, as shown in the publication.

However, if the thickness of the base film is increased, the following problems occur. That is, when the unnecessary portion of the underlayer film is removed by dry etching such as ion milling after the formation of the plating layer, the substance forming the underlayer film is redeposited on the side surface of the plating layer, and as a result, the magnetic pole width is reduced. Grows larger. Then, as the thickness of the underlayer film increases, the re-deposition amount of the substance increases, and the increase amount of the magnetic pole width increases.

As described above, the increase of the magnetic pole width due to the re-deposition of the substance forming the underlayer film becomes a serious problem as the magnetic pole width becomes smaller. This is because even if the thickness of the underlayer film is constant and the amount of redeposition of the substance forming the underlayer film is constant, the ratio of the increase amount of the magnetic pole width to the magnetic pole width becomes larger as the magnetic pole width becomes smaller.

The present invention has been made in view of the above problems, and an object thereof is to provide a thin film magnetic head capable of accurately controlling the magnetic pole width even when the magnetic pole width is small, and a manufacturing method thereof. .

[0010]

A thin film magnetic head according to the present invention includes a medium facing surface facing a recording medium and magnetic pole portions magnetically connected to each other and facing each other on the medium facing surface side, and each has at least one magnetic pole portion. First and second magnetic layers including two layers, a gap layer provided between the magnetic pole portion of the first magnetic layer and the magnetic pole portion of the second magnetic layer, and at least a part of the first and second magnetic layers. A thin film coil provided between the two magnetic layers and insulated from the first and second magnetic layers, wherein at least one of the first magnetic layer and the second magnetic layer is a track. The thin-film magnetic head further includes a track width defining layer formed by a plating method and including a magnetic pole portion defining the width, and the thin film magnetic head further serves as an underlayer for plating the track width defining layer and has a thickness of 0.18 times the track width. Equipped with a base film that is Those were.

In the thin film magnetic head of the present invention, the track width defining layer is formed by the plating method by setting the thickness of the underlayer film, which is the base for plating the track width defining layer, to 0.18 times the track width or less. When the unnecessary portion of the underlayer film is later removed, the increase in the magnetic pole width due to the substance forming the underlayer film reattaching to the side surface of the track width defining layer can be suppressed within the allowable range.

In the thin film magnetic head of the present invention, the track width is 0.90 μm or less and the thickness of the underlayer film is 0.0
The base film is made of a magnetic material having a saturation magnetic flux density of 2.0 T (tesla) or more .

A method of manufacturing a thin film magnetic head according to the present invention includes a medium facing surface facing a recording medium and magnetic pole portions magnetically coupled to each other and facing each other on the medium facing surface side, each including at least one layer. Including first and second
A magnetic layer, a gap layer provided between the magnetic pole portion of the first magnetic layer and the magnetic pole portion of the second magnetic layer, and at least a part of the gap layer between the first and second magnetic layers. 1 and 2
A method of manufacturing a thin film magnetic head having a thin film coil provided in an insulated state with respect to the magnetic layer of
A step of forming a first magnetic layer, a step of forming a gap layer on the first magnetic layer, a step of forming a second magnetic layer on the gap layer, and a step of forming a thin film coil. At least one of the step of forming the first magnetic layer and the step of forming the second magnetic layer includes forming a track width defining layer including a magnetic pole portion defining the track width by a plating method, The manufacturing method further includes a step of forming an underlayer film which is a base for plating and has a thickness of 0.18 times or less of the track width before forming the track width defining layer, and the track width defining layer is formed. It is provided with a step of removing an unnecessary portion of the base film later.

In the method of manufacturing the thin film magnetic head of the present invention,
By setting the thickness of the underlayer film, which is the underlayer for plating the track width defining layer, to 0.18 times the track width or less, unnecessary portions of the underlayer film are removed after the track width defining layer is formed by the plating method. In doing so, it is possible to suppress the increase in the magnetic pole width within the allowable range due to the substance forming the underlayer reattaching to the side surface of the track width defining layer.

In the method of manufacturing a thin film magnetic head of the present invention, the track width is 0.90 μm or less and the thickness of the underlayer film is
The base film is made of a magnetic material having a saturation magnetic flux density of 2.0 T or more .

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. First, an outline of a method of manufacturing a thin film magnetic head according to an embodiment of the present invention will be described with reference to FIGS. 1 to 6, (a) shows a cross section perpendicular to the air bearing surface, and (b) shows a cross section parallel to the air bearing surface of the magnetic pole portion.

In the method of manufacturing a thin film magnetic head according to this embodiment, first, as shown in FIG. 1, sputtering is performed on a substrate 1 made of a ceramic material such as AlTiC (Al ₂ O ₃ .TiC). Alumina (A
l ₂ O ₃₎ an insulating layer 2 made of an insulating material such as, for example, 1
It is formed to a thickness of 5 μm. Next, a lower shield layer 3 for a reproducing head, which is made of a magnetic material such as permalloy (NiFe), is formed on the insulating layer 2 by a sputtering method, a plating method, or the like to have a thickness of, for example, about 3 μm.

Next, a lower shield gap film 4 made of an insulating material such as alumina is formed on the lower shield layer 3 by a sputtering method or the like to have a thickness of, for example, 10 to 200 nm. Next, the MR element 5 for reproduction is formed on the lower shield gap film 4 by a sputtering method or the like.
Is formed to have a thickness of several tens nm, for example. As the MR element 5, an element using a magneto-sensitive film exhibiting a magnetoresistive effect such as an AMR (anisotropic magnetoresistive effect) element, a GMR (giant magnetoresistive effect) element or a TMR (tunnel magnetoresistive effect) element is used. be able to.

Next, on the lower shield gap film 4,
A pair of electrode layers 6 electrically connected to the MR element 5 are formed with a thickness of several tens nm by a sputtering method or the like. Next, the lower shield gap film 4 and the MR element 5
An upper shield gap film 7 made of an insulating material such as alumina is formed on the upper surface by, for example, a sputtering method.
It is formed to a thickness of 0 to 200 nm.

Each layer constituting the reproducing head is patterned by a general etching method using a resist pattern, a lift-off method or a method using these in combination.

Next, on the upper shield gap film 7,
An upper shield layer / lower magnetic pole layer (hereinafter, referred to as lower magnetic pole layer) 8 made of a magnetic material and used for both a reproducing head and a recording head is formed to have a thickness of 3 to 4 μm, for example. The magnetic material used for the bottom pole layer 8 is NiF.
Soft magnetic materials such as e, CoFe, CoFeNi, and FeN. The lower magnetic pole layer 8 is formed by a sputtering method, a plating method, or the like.

In place of the lower magnetic pole layer 8, an upper shield layer, a separation layer made of a non-magnetic material such as alumina formed on the upper shield layer by a sputtering method, and the like. The formed lower magnetic layer may be provided.

Next, as shown in FIG. 2, the bottom pole layer 8 is formed.
A recording gap layer 9 made of an insulating material such as alumina is formed on the top surface of the recording layer by, for example, 150 to 3 by a sputtering method or the like.
It is formed to a thickness of 00 nm. Next, for magnetic path formation,
The recording gap layer 9 is partially etched in the central portion of a thin film coil described later to form a contact hole 9a.

Next, the first layer portion 10 of the thin film coil made of, for example, copper (Cu) is formed on the recording gap layer 9 to have a thickness of, for example, 2 to 3 μm. In FIG. 2A, reference numeral 10a represents a connecting portion of the first layer portion 10 that is connected to a second layer portion 15 of a thin film coil described later. The first layer portion 10 is wound around the contact hole 9a.

Next, as shown in FIG. 3, an organic insulating material having fluidity when heated, such as a photoresist, is formed so as to cover the first layer portion 10 of the thin film coil and the recording gap layer 9 around the first layer portion 10. The insulating layer 11 is formed in a predetermined pattern. Next, heat treatment is performed at a predetermined temperature to flatten the surface of the insulating layer 11. By this heat treatment, the insulating layer 1
Each of the outer and inner edge portions of 1 has a rounded slope shape.

Next, in the region from the slope portion on the air bearing surface 30 side (left side in FIG. 3A) of the insulating layer 11 to the air bearing surface 30 side, which will be described later, the recording gap layer 9 and the insulating layer 11 are formed. A track width defining layer 12a of the top pole layer 12 is formed on the top of the top pole layer 12 with a magnetic material for a recording head. The upper magnetic pole layer 12 is composed of the track width defining layer 12a, and a connecting portion layer 12b and a yoke portion layer 12c which will be described later. The track width defining layer 12a is formed by a plating method, as described later in detail.

The track width defining layer 12a is formed on the recording gap layer 9, and the tip portion 12a ₁ which becomes the magnetic pole portion of the upper magnetic pole layer 12 and the air bearing surface 30 of the insulating layer 11 are formed.
And a connecting portion 12a ₂ formed on the side slope portion and connected to the yoke portion layer 12c. Tip 12a ₁
Is equal to the recording track width. That is,
The tip portion 12a ₁ defines the recording track width.

When forming the track width defining layer 12a, at the same time, the connecting portion layer 12b made of a magnetic material is formed on the contact hole 9a, and the connecting portion 10a is formed.
A connection layer 13 made of a magnetic material is formed thereon. The coupling portion layer 12b constitutes a portion of the upper magnetic pole layer 12 that is magnetically coupled to the lower magnetic pole layer 8.

Next, in the periphery of the track width defining layer 12a, at least a part of the recording gap layer 9 and the magnetic pole portion of the lower magnetic pole layer 8 on the recording gap layer 9 side is etched using the track width defining layer 12a as a mask. Reactive ion etching is used for etching the recording gap layer 9, and ion milling is used for etching the lower magnetic pole layer 8. As shown in FIG. 3B, side walls of at least a part of the magnetic pole portion of the upper magnetic pole layer 12 (the tip portion 12a ₁ of the track width defining layer 12a), the recording gap layer 9 and the lower magnetic pole layer 8. A structure in which is vertically self-aligned is called a Trim structure.

Next, as shown in FIG. 4, an insulating layer 14 made of an inorganic insulating material such as alumina is formed on the entire surface by, for example, 3 layers.
It is formed to a thickness of ˜4 μm. Next, the insulating layer 14 is
For example, by chemical mechanical polishing, the track width defining layer 12
a, the connecting portion layer 12b and the surface of the connecting layer 13 are polished and planarized.

Next, as shown in FIG. 5, a second layer portion 15 of a thin-film coil made of, for example, copper (Cu) is formed on the flattened insulating layer 14 to have a thickness of, for example, 2 to 3 μm. To do. In FIG. 5A, the reference numeral 15a indicates the second
In the layer portion 15, the connection portion connected to the connection portion 10a of the first layer portion 10 of the thin-film coil via the connection layer 13 is shown. The second layer portion 15 is wound around the connecting portion layer 12b.

Next, an insulating layer 16 made of an organic insulating material having fluidity when heated, such as a photoresist, is formed into a predetermined pattern so as to cover the second layer portion 15 of the thin-film coil and the insulating layer 14 around it. Form. Next, the insulating layer 16
Is heat-treated at a predetermined temperature in order to flatten the surface. By this heat treatment, each of the outer and inner edge portions of the insulating layer 16 has a rounded slope shape.

Next, as shown in FIG. 6, the track width defining layer 12a, the insulating layers 14 and 16 and the connecting portion layer 12b.
A yoke part layer 12c forming the yoke part of the top pole layer 12 is formed on the top of the top pole layer 12 by a magnetic material such as permalloy for a recording head. An end of the yoke portion layer 12c on the air bearing surface 30 side is arranged at a position apart from the air bearing surface 30. In addition, the yoke portion layer 12c
Are connected to the bottom pole layer 8 via the coupling portion layer 12b.

Next, an overcoat layer 17 made of alumina, for example, is formed so as to cover the entire surface. Finally, the slider including each of the above layers is machined to form the air bearing surface 30 of the thin film magnetic head including the recording head and the reproducing head, thus completing the thin film magnetic head.

The thin-film magnetic head according to the present embodiment manufactured in this manner has the medium facing surface (air bearing surface 30) facing the recording medium, the reproducing head and the recording head (induction type electromagnetic conversion element). I have it. The reproducing head is MR element 5 and a part of the air bearing surface 30 side is M
It has a lower shield layer 3 for shielding the MR element 5 and an upper shield layer (lower magnetic pole layer 8) which are arranged so as to face each other with the R element 5 interposed therebetween.

The recording heads are magnetically coupled to each other,
A lower magnetic pole layer 8 and an upper magnetic pole layer 12 each including at least one layer that includes magnetic pole portions facing each other on the air bearing surface 30 side, and a magnetic pole portion of the lower magnetic pole layer 8 and a magnetic pole portion of the upper magnetic pole layer 12. The recording gap layer 9 is provided between the thin film coils, and the thin film coils 10 and 15 are disposed at least partially between the lower magnetic pole layer 8 and the upper magnetic pole layer 12 so as to be insulated from them. ing.
In the thin film magnetic head according to the present embodiment, as shown in FIG. 6A, the insulating layer 11 is removed from the air bearing surface 30.
The length up to the end on the air bearing surface 30 side is the throat height TH. The throat height is the length (height) from the end on the air bearing surface side to the end on the opposite side of the portion where the two pole layers face each other with the recording gap layer in between.

In the present embodiment, the lower magnetic pole layer 8 corresponds to the first magnetic layer of the present invention, and the upper magnetic pole layer 12 corresponds to the second magnetic layer of the present invention.

Next, the method of forming the track width defining layer 12a of the top pole layer 12 will be described in detail with reference to FIGS. In the method of forming the track width defining layer 12a, first, as shown in FIG. 7, the base film 21 serving as a base for plating is formed on the recording gap layer 9 by, for example, the sputtering method. The base film 21
Is made of a magnetic material. Further, in the present embodiment, the thickness of the base film 21 is set to 0.18 times or less the recording track width.
Further, in this embodiment, the recording track width is 0.90 μm.
In the case of m or less, the base film 21 is made of FeN or the like and has a thickness of 2.0
It is formed of a magnetic material having a saturation magnetic flux density of T or higher.

Next, as shown in FIG. 8, a photoresist layer is formed on the base film 21, and the photoresist layer is patterned by a photolithography process.
A frame (outer frame) 22 for plating is formed.

Next, as shown in FIG.
Is used to form a track width defining layer 12a on the base film 21 by plating using the base film 21 formed previously as an electrode.

Next, as shown in FIG.
2 is removed, and an unnecessary portion of the base film 21 other than the portion existing under the track width defining layer 12a is removed by dry etching such as ion milling. Through the above steps, as shown in FIG. 11, the base film 21 and the track width defining layer 12a are formed on the recording gap layer 9.

By the way, as shown in FIG. 12, when the unnecessary portion of the base film 21 is removed by dry etching such as ion milling, the atoms and molecules of the substance forming the base film 21 are removed. , Scraped off from the base film 21, and a part of it is reattached to the side surface of the track width defining layer 12a,
The redeposition film 23 is formed. As a result, the magnetic pole width is the width of the combined portion of the track width defining layer 12a and the redeposited film 23, which is larger than the width of the track width defining layer 12a. Therefore, even if the width of the track width defining layer 12a is formed to be equal to the desired recording track width, the actual magnetic pole width becomes larger than the desired recording track width.

The present inventor conducted an experiment to examine the relationship between the thickness of the base film 21 and the thickness of the redeposited film 23 when an unnecessary portion of the base film 21 was removed by using ion milling. In this experiment, NiFe (Ni: 50% by weight, Fe: 50% by weight) was used as the material of the base film 21, and the angle formed by the normal line to the surface of the base film 21 and the ion beam was 0 °. . Further, the thickness of the redeposition film 23 is
The total thickness of the redeposited film 23 formed on both side surfaces of the track width defining layer 12a was set. The result of the experiment is shown in FIG.
The straight line in FIG. 13 is a line that approximates the distribution of points representing the correspondence relationship between the thickness of the base film 21 and the thickness of the redeposition film 23.
From FIG. 13, it can be seen that the thickness of the redeposition film 23 is about 1.1 times the thickness of the base film 21.

On the other hand, the following table shows a typical example of the relationship between the recording density and the required recording track width and its tolerance. In this table, “Gbpsi” represents gigabit / (inch) ² , “kdpi” represents kilodots / inch, and “ktpi” represents kilotracks / inch.

[0045]

[Table 1]

As can be seen from the above table, at an areal recording density of 20 gigabits / (inch) ² or more, the required recording track width is on the order of submicrons. Also,
At areal recording density of 30 Gbit / (inch) ² or more,
The tolerance of the recording track width is required to be 0.10 μm or less. From the above table, it can be seen that the tolerance of the recording track width is about 20% of the recording track width.

The thickness of the above-mentioned redeposition film 23 must be within the tolerance of the recording track width. From the above, the following relationship is obtained.

Tolerance of recording track width = recording track width ×
0.2 ≧ thickness of redeposition film 23 = thickness of base film 21 × 1.
1

From the above relationship, the relationship between the thickness of the base film 21 and the recording track width is as follows.

[0050] Thickness of base film 21 ≦ recording track width × 0.18

For the above reasons, the thickness of the base film 21 is set to 0.18 times or less the recording track width in this embodiment.

Next, the base film 21 and the track width defining layer 12
14 and 15 show the results of an experiment conducted to obtain the relationship between the recording track width and the overwrite characteristic for three types of thin film magnetic heads in which at least one of a is different.
Shown in.

In this experiment, the track width defining layer 12a
Is formed on the base film 21 by a plating method.
And a second layer formed on the first layer by a plating method.

The characteristics of the three types of thin film magnetic heads are shown in FIG.
Also, in FIG. 15, three types of points (square, triangle, x) are used. Base film 2 for three types of thin film magnetic heads
The compositions, the saturation magnetic flux densities, and the thicknesses of the first, first, and second layers are as shown in the table below. In the table below,
"Ni50Fe" is NiFe (Ni: 50 wt%, F
e: 50% by weight), "Ni82Fe" is NiF
e (Ni: 82% by weight, Fe: 18% by weight). 14 and 15, the chain double-dashed line is a line that approximates the distribution of square points, the broken line is a straight line that approximates the distribution of triangular points, and the solid line approximates the distribution of points marked x. It is a straight line.

[0055]

[Table 2]

As can be seen from FIG. 14, the material of the base film 21 is NiFe (Ni: 50% by weight, Fe: 50% by weight).
In the above head, when the recording track width becomes 0.90 μm or less, the overwrite characteristic deteriorates by slightly less than 3 dB as the recording track width becomes smaller by 0.10 μm until the recording track width becomes about 0.70 μm. In contrast to this head, the overwrite characteristic is improved by about 2 to 5 dB in the two types of heads in which the material of the base film 21 is FeN.

As can be seen from FIG. 15, the base film 2
In the head in which the material No. 1 is NiFe (Ni: 50% by weight, Fe: 50% by weight), the recording track width is 0.60 μm.
Below m, the overwrite characteristic deteriorates by about 2 dB as the recording track width decreases by 0.10 μm. In contrast to this head, two types of heads in which the base film 21 is made of FeN have overwrite characteristics of 3 to 5d.
Improve about B.

As described above, when the recording track width becomes smaller, the recording characteristics deteriorate. However, if the base film 21 is 2.
By using a magnetic material having a saturation magnetic flux density of 0T or more, it is possible to suppress the deterioration of the recording characteristics due to the reduction of the recording track width. Particularly, when the recording track width is 0.90 μm or less, it is preferable that the underlayer film 21 is formed of a magnetic material having a saturation magnetic flux density of 2.0 T or more in order to improve the recording characteristics.

Next, a thickness of 0.
The magnetic characteristics (relationship between the magnetic field and the magnetic flux density) of the three kinds of underlayer films 21 of 05 μm, 0.10 μm, and 0.50 μm are shown in FIGS. 16, 17, and 18, respectively. 16 to 18, the solid line shows the characteristic in the difficult magnetization direction, and the broken line shows the characteristic in the easy magnetization direction.

As shown in FIG. 16, the thickness is 0.05 μm.
The underlying film 21 of No. 1 does not have sufficient soft magnetic characteristics. However, the saturation magnetic flux density in FIGS. 16 to 18 is almost constant regardless of the thickness of the base film 21. The saturation magnetic flux density is important in the magnetic characteristics required for the underlayer film 21 in an actual thin film magnetic head. Therefore, Fe
Even with the base film 21 formed of N and having a thickness of 0.05 μm, the recording characteristics of the thin film magnetic head can be improved as shown in FIGS.

As described above, in the thin film magnetic head or the method of manufacturing the thin film magnetic head according to the present embodiment, the thickness of the underlayer film 21 serving as the underlayer for plating the track width defining layer 12a is set to 0. 18 times or less. As a result, the track width defining layer 1 is formed by the plating method.
When the unnecessary portion of the underlayer film 21 is removed after forming 2a, the increase in the magnetic pole width due to the substance forming the underlayer film 21 reattaching to the side surface of the track width defining layer 12a is within the allowable range. It becomes possible to suppress. As a result, according to the present embodiment, it is possible to accurately control the magnetic pole width even when the magnetic pole width is small.

Further, in the present embodiment, when the track width is 0.90 μm or less, the base film 21 has a thickness of 2.0 T.
Since it is made of a magnetic material having the above saturation magnetic flux density, the recording characteristics can be improved even when the magnetic pole width is small.

The present invention is not limited to the above embodiment, and various modifications can be made. For example, in the embodiment, the upper magnetic pole layer 12 including the magnetic pole portion that defines the recording track width is the track width defining layer 12a and the coupling portion layer 12b.
And the yoke portion layer 12c, the present invention can also be applied to the case where the top pole layer 12 is formed of one layer. In this case, one layer forming the top pole layer 12 becomes the track width defining layer.

In the above embodiment, the thin film magnetic head having the structure in which the MR element for reading is formed on the substrate side and the inductive electromagnetic conversion element for writing is laminated on the MR element is described. The order may be reversed.

That is, an inductive electromagnetic conversion element for writing may be formed on the substrate side, and an MR element for reading may be formed thereon. In such a structure, for example, the magnetic film having the function of the upper magnetic pole layer described in the above embodiment is formed as the lower magnetic pole layer on the substrate side, and the magnetic gap film is formed so as to face the recording gap film. This can be realized by forming the magnetic film having the function of the lower magnetic pole layer shown in the embodiment as the upper magnetic pole layer.

The present invention can also be applied to a thin-film magnetic head dedicated to recording, which is provided with only an induction type electromagnetic conversion element, and a thin film magnetic head for recording and reproducing by the induction type electromagnetic conversion element.

[0067]

As described above, according to the thin film magnetic head or the method of manufacturing the same of the present invention, the thickness of the underlayer film, which is the underlayer for plating the track width defining layer, is 0.18 times or less the track width. Therefore, when the unnecessary portion of the underlayer film is removed after the track width defining layer is formed by the plating method, the magnetic pole width of the It is possible to keep the increase within the allowable range. As a result, according to the present invention, it is possible to accurately control the magnetic pole width even when the magnetic pole width is small.

According to the thin film magnetic head or the method of manufacturing the same of the present invention , the track width is 0.90 μm or less,
The thickness of the base film is 0.05 μm or less, and the base film is 2.0T
Since it is made of a magnetic material having the above saturation magnetic flux density, there is an effect that the recording characteristics can be improved even when the magnetic pole width is small.

[Brief description of drawings]

FIG. 1 is a sectional view for explaining an outline of a method of manufacturing a thin film magnetic head according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view for explaining a step following FIG.

FIG. 3 is a cross-sectional view for explaining a step following the step of FIG.

FIG. 4 is a cross-sectional view for explaining a step following the step of FIG.

FIG. 5 is a cross-sectional view for explaining a step following the step of FIG.

FIG. 6 is a cross-sectional view for explaining a step following the step of FIG.

FIG. 7 is a cross-sectional view for explaining the method of forming the track width defining layer of the top pole layer in the embodiment of the present invention.

FIG. 8 is a cross-sectional view for explaining a process following the process in FIG.

FIG. 9 is a cross-sectional view for explaining a step following the step of FIG.

FIG. 10 is a cross-sectional view illustrating a step following the step of FIG.

FIG. 11 is a cross-sectional view for explaining a step following FIG.

FIG. 12 is an explanatory diagram for explaining a problem in removing an unnecessary portion of the base film.

FIG. 13 is a characteristic diagram showing the relationship between the thickness of a base film and the thickness of a redeposited film.

FIG. 14 is a characteristic diagram showing a relationship between a recording track width and an overwrite characteristic.

FIG. 15 is a characteristic diagram showing a relationship between a recording track width and an overwrite characteristic.

FIG. 16 is a characteristic diagram showing magnetic characteristics of a 0.05 μm thick underlayer.

FIG. 17 is a characteristic diagram showing magnetic characteristics of a 0.10 μm thick underlayer.

FIG. 18 is a characteristic diagram showing magnetic characteristics of an underlayer having a thickness of 0.50 μm.

[Explanation of symbols]

1 ... Substrate, 2 ... Insulating layer, 3 ... Bottom shield layer, 5 ... MR
Element, 8 ... Lower magnetic pole layer, 9 ... Recording gap layer, 10 ... First layer portion of thin film coil, 12 ... Upper magnetic pole layer, 12a ... Track width defining layer, 12b ... Coupling partial layer, 12c ... Yoke partial layer, 15 ... second layer portion of thin film coil, 21 ... base film, 22 ... frame.

Continuation of front page (56) Reference JP-A-11-175914 (JP, A) JP-A-11-339222 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) G11B 5 / 31

Claims (2)

(57) [Claims] 1. A first and second magnetic element including a medium facing surface facing a recording medium and magnetic pole portions magnetically coupled to each other and facing each other on the medium facing surface side, each including at least one layer. A layer, a gap layer provided between the magnetic pole portion of the first magnetic layer and the magnetic pole portion of the second magnetic layer, and at least a portion between the first and second magnetic layers, A thin-film magnetic head comprising: a thin-film coil provided in an insulated state from the first and second magnetic layers, wherein at least one of the first magnetic layer and the second magnetic layer is
The thin film magnetic head further includes a track width defining layer formed by a plating method and including a magnetic pole portion defining the track width. The thin film magnetic head further serves as an underlayer for plating the track width defining layer and has a thickness of 0. 18 times or less comprising a base film, wherein the track width is less than 0.90 .mu.m, the underlayer
Has a thickness of 0.05 μm or less, and the base film has a thickness of 2.0 μm.
A thin film magnetic head made of a magnetic material having a saturation magnetic flux density of T or more . 2. A first and second magnetic layer including a medium facing surface facing a recording medium and magnetic pole portions magnetically coupled to each other and facing each other on the medium facing surface side, each including at least one layer. A layer, a gap layer provided between the magnetic pole portion of the first magnetic layer and the magnetic pole portion of the second magnetic layer, and at least a portion between the first and second magnetic layers, A method of manufacturing a thin-film magnetic head comprising: a thin-film coil provided in a state of being insulated from the first and second magnetic layers, the method comprising: forming the first magnetic layer; A step of forming the gap layer on the first magnetic layer; a step of forming the second magnetic layer on the gap layer; and a step of forming the thin-film coil. Forming a layer and forming a second magnetic layer In at least one of the steps, a track width defining layer including a magnetic pole portion that defines the track width is formed by a plating method, and the thin film magnetic head manufacturing method further includes: A step of forming an underlayer film which becomes an underlayer and has a thickness of 0.18 times or less the track width; and a step of removing an unnecessary portion of the underlayer film after forming the track width defining layer , The track width is 0.90 μm or less,
Has a thickness of 0.05 μm or less, and the base film has a thickness of 2.0 μm.
A method of manufacturing a thin-film magnetic head, comprising a magnetic material having a saturation magnetic flux density of T or more .