JP3424905B2 - 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 magnetic conversion element for writing 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 is a composite thin film having a structure in which a recording head having an inductive magnetic conversion element for writing and a reproducing head having a magnetoresistive (hereinafter referred to as MR) element for reading are laminated. Magnetic heads are widely used. An anisotropic magnetoresistive (hereinafter referred to as AMR (Anisotropic Magneto Resi
stive). ) There is an AMR element using the effect and a GMR element using the giant magnetoresistive (hereinafter referred to as GMR (Giant Magneto Resistive)) effect. A reproducing head using an AMR element is called an AMR head or simply an MR head, and a reproducing head using a GMR element is a GMR head.
Called the head. The AMR head is used as a reproducing head whose areal recording density exceeds 1 gigabit / (inch) ² , and the GMR head has an areal recording density of 3 gigabit / (inch) ^2.
(Inch) Used as a playback head of more than ² .

An AMR head is an AM having an AMR effect.
It has an R film. The GMR head uses an AMR film as a GM
It is replaced with a GMR film having an R effect and is structurally similar to an AMR head. However, the GMR film is AM
It exhibits a larger resistance change than the R film when the same external magnetic field is applied. Therefore, it is said that the GMR head can increase the reproduction output by about 3 to 5 times that of the AMR head.

As a method of improving the performance of the reproducing head, there is a method of changing the MR film. Generally, the AMR film is a film made of a magnetic material having an MR effect and has a single-layer structure. On the other hand, many GMR films have a multilayer structure in which a plurality of films are combined. There are several types of mechanisms that cause the GMR effect, and the layer structure of the GMR film changes depending on the mechanism. GMR
As the film, a superlattice GMR film, a granular film, a spin valve film, etc. have been proposed, but they have a relatively simple structure and show a large resistance change even in a weak magnetic field, and are intended for mass production.
A spin valve film is effective as the MR film. In this way, the reproducing head may change the MR film from the AMR film to the G film, for example.
By changing to a material with excellent magnetoresistive sensitivity such as MR film,
The objective of improving performance can be easily achieved.

The factors that determine the performance of the reproducing head include the pattern width, especially the MR height, in addition to the selection of the material as described above. The MR height refers to the length (height) from the end on the air bearing surface side of the MR element to the end on the opposite side, and is controlled by the amount of polishing when processing the air bearing surface. . The air bearing surface mentioned here is the surface of the thin-film magnetic head that faces the magnetic recording medium, and is also called the track surface.

On the other hand, as the performance of the reproducing head is improved, the performance of the recording head is also required to be improved. Among the performances of the recording head, in order to increase the recording density, it is necessary to increase the track density in the magnetic recording medium. To this end, the width of the lower magnetic pole (bottom pole) and the upper magnetic pole (top pole) formed above and below the write gap is narrowed from a few microns to the submicron order. It is necessary to realize a recording head having a narrow track structure, and semiconductor processing technology is used to achieve this.

[0007] Another factor that determines the performance of the recording head is throat height (TH). The throat height is the length (height) of the magnetic pole portion from the air bearing surface to the edge of the insulating layer that electrically separates the thin-film coil for magnetic flux generation. To improve the performance of the recording head, it is desired to reduce the throat height. The throat height is also controlled by the polishing amount when processing the air bearing surface.

Further, in order to improve the performance of the recording head, it has been proposed to shorten the length of the lower magnetic pole and the upper magnetic pole that sandwich the thin film coil (hereinafter referred to as the magnetic path length).

As described above, in order to improve the performance of the thin film magnetic head, it is important to form the recording head and the reproducing head in a well-balanced manner.

The structure and method of forming the thin-film coil, which is the determining factor of the magnetic path length, will be described below with reference to the drawings.

28 to 35 show the main part of the manufacturing process of a composite thin film magnetic head having an MR element as an example of a conventional standard composite thin film magnetic head.
These figures show cross sections when a main part of the intermediate product in each step is cut by a plane perpendicular to the air bearing surface.
Here, a case of a composite type thin film magnetic head in which an inductive recording thin film magnetic head is laminated on a magnetoresistive reproducing thin film magnetic head will be exemplified.

First, as shown in FIG. 28, an insulating layer 1 made of, for example, alumina (Al ₂ O ₃ ) is formed on a substrate 101 made of, for example, AlTiC (Al ₂ O ₃ .TiC).
02 is deposited to a thickness of about 5 to 10 μm. This insulating layer 1
02, the MR element of the reproducing head (MR film 1 described later).
The lower shield layer 103 which constitutes the magnetic shield layer for protecting (05) from the influence of the external magnetic field is formed with a thickness of 3 to 4 μm. Next, for example, alumina is sputter-deposited to a thickness of 100 to 200 nm on the lower shield layer 103 to form a shield gap film 104, and then an MR film 105 for forming an MR element of a reproducing head is formed thereon. It is formed to have a thickness of several tens of nm and is formed into a desired shape by high precision photolithography. Next, the shield gap film 106 is formed on the shield gap film 104 and the MR layer 105, and the MR film 105 is shielded by the shield gap films 104 and 10.
It is buried in 6. Next, a magnetic layer 107 made of permalloy (NiFe) 3 is formed on the shield gap film 106.
It is formed to have a film thickness of ˜4 μm. The magnetic layer 107 has a function as an upper shield layer that magnetically shields the GMR element of the reproducing head together with the above-mentioned lower shield layer 103, and also has a function as a lower magnetic pole of the recording head. Here, for the sake of convenience of description, the magnetic layer 107 will be simply referred to as the lower magnetic pole 107, focusing on the fact that the magnetic layer 107 is one of the magnetic layers forming the recording head.

Next, as shown in FIG. 29, the lower magnetic pole 1
The recording gap layer 109 made of a non-magnetic material such as alumina is formed on the layer 07 with a thickness of about 200 nm, and the recording gap layer 1 is formed except for the portion constituting the magnetic pole portion later.
09, a photoresist 110 for determining the reference position of the throat height is formed, and further, copper (C
thin seed layer 11 composed of u) or the like and having a thickness of about 100 nm
1 is formed by sputtering. The seed layer 111 is
It serves as a seed when the thin film coil is formed later by electroplating. Next, a thick photoresist 112 having a thickness of 3 to 4 μm is formed on the seed layer 111,
A spiral opening 113 reaching the seed layer 111 is formed in the photoresist 112 by photolithography. The depth of this opening 113 is equal to the film thickness, and the width is 2 μm.
It is a degree. The width of the spiral photoresist pattern formed by the opening 113 is also about 2 μm.

Next, as shown in FIG. 30, electroplating of copper is performed using a plating solution of copper sulfate to form a coil-shaped coil in the opening 113 of the photoresist 112 to form the first-layer thin-film coil. Form body 114. This coiled body 1
The film thickness of 14 is preferably smaller than the depth of the opening 113, and is, for example, 2 to 3 μm.

Next, as shown in FIG. 31, after removing the photoresist 112, as shown in FIG. 32, milling by an argon ion beam IB (hereinafter, referred to as ion milling) is performed to form a seed layer. By removing 111, the winding bodies of the coiled body 114 are separated from each other to form the first layer coil 114a. At the time of this ion milling, the ion milling is performed at 5 to 10 ° in order to prevent the seed layer 111 at the bottom between the winding bodies of the coiled body 114 from protruding and remaining outside the thin film coil. Perform at an angle. When the ion milling is performed at an angle close to vertical as described above, the material forming the seed layer 111 may be scattered and redeposited by the impact of the ion beam, and the winding bodies may not be completely separated. Therefore, it is necessary to make the winding body spacing of the coiled body 114 relatively wide. This point will be described later.

Next, as shown in FIG. 33, a photoresist 115 is formed so as to cover the first layer coil 114a and the photoresist 110, and then the first layer coil 114a is planarized and described later. For the purpose of determining the apex angle, heat treatment is performed at a temperature of 250 ° C., for example. Next, as shown in FIG.
By the same process as the process shown in FIG. 32, the second layer coil 117 a including the seed layer 116 is formed on the photoresist 115, and the photoresist 118 is further formed. Next, as shown in FIG. 34, the coils 114a,
At a position rearward from 117a (on the right side in FIG. 34), the recording gap layer 109 is selectively etched to form a magnetic path, and then an upper magnetic pole 119 made of permalloy or the like is formed to a film thickness of 3 to 5 μm. . The upper magnetic pole 119 is in contact with the lower magnetic pole 107 and is magnetically connected to the lower magnetic pole 107 at a position behind the coils 114a and 117a.

Next, as shown in FIG. 35, the upper magnetic pole 1
The recording gap layer 109 and the lower magnetic pole 107 are etched by about 0.5 μm by using the magnetic pole portion 119a of 19 as a mask to form a trim structure described later, and then, as shown in FIG. An overcoat layer 120 made of alumina is formed. Note that FIG. 35 shows a state in which the laminated structure in FIG. 34 is cut along a plane that passes through the MR layer 105 and is parallel to the air bearing surface 122. In this figure, the shield gap layers 104 and 106 that electrically insulate the MR film 105 from other layers and shield it magnetically are shown separately, and the MR film 1 is also shown.
Also shown are lead layers 121a and 121b made of a conductive layer for making an electrical connection to 05. However, the illustration of the overcoat layer 120 is omitted.

Finally, the slider is machined to form the air bearing surfaces 122 of the recording head and the reproducing head as shown in FIG. 34, and the thin film magnetic head is completed.

In FIG. 34, TH represents throat height and MR-H represents MR height. In addition to these throat height and MR height, as a factor that determines the performance of the thin film magnetic head, there is the Apex Angle indicated by θ in FIG. The apex angle corresponds to the photoresist layers 110 and 11
The angle between the straight line S connecting the corners of the side surfaces of the air bearing surface side of 5, 118 and the upper surface of the upper magnetic pole 119.

In FIG. 35, P2W represents the magnetic pole width. As shown in this figure, the magnetic pole portion 119a of the upper magnetic pole 119, the recording gap layer 109, and the lower magnetic pole 10 are formed.
A structure in which the respective side walls of the part 107a of 7 are vertically formed in a self-aligned manner is called a trim structure. With this trim structure, it is possible to prevent an increase in the effective track width due to the spread of the magnetic flux generated when writing a narrow track.

In the actual manufacture of the thin film magnetic head, a wafer having a large number of the above-described structures is divided into bars in which a large number of thin film magnetic heads are arranged, and the side surfaces of the bars are ground to polish the air bearing surface 122. (FIG. 34). In the process of forming the air bearing surface 122, the MR film 105 is also polished to obtain a composite type thin film magnetic head having a desired throat height and MR height. Furthermore, in an actual thin film magnetic head,
Although contact pads for making electrical connection to the thin-film coils 114a and 117a and the MR film 105 are formed, they are not shown in the drawings described above.

[0022]

The conventional composite type thin film magnetic head formed as described above has the following problems, especially in terms of miniaturization of the recording head.

Generally, by shortening the magnetic path length LM, the flux rising time (Flux) of the induction type thin film magnetic head is increased.
Rise Time) and non-linear transition shift (Non-line
ar Transition Shift: NLTS) characteristics and overwriting
e) It is known that the characteristics can be improved. Here, as shown in FIG. 34, the magnetic path length LM is the length of the lower magnetic pole 107 and the upper magnetic pole 119 in the portion surrounding the first layer coil 114a and the second layer coil 117a (that is, Recording gap layer 10 from the air bearing surface
9 is the distance to the opening formed in FIG. In addition, the magnetic flux rising time depends on the first layer coil 114a and the second layer.
This is the time from when a current is applied to the thin film coil including the coil 117a of the layer until the magnetic flux density in the magnetic circuit including the lower magnetic pole 107 and the upper magnetic pole 119 reaches a predetermined level, which influences the high frequency characteristics during recording. Is. In addition, the non-linear transition shift is the position of the transition (the part where the magnetization direction is reversed) where the magnetic flux from the magnetic domain recorded immediately before is interacting with the magnetic flux of the recording head during data recording. Is a phenomenon in which the data recording position is accurate, and thus the areal density characteristic at the time of recording is affected.

In order to shorten the magnetic path length LM, it is necessary to shorten the coil bundle width LC of the first layer coil 114a and the second layer coil 117a surrounded by the lower magnetic pole 107 and the upper magnetic pole 119. is there. This coil bundle width L
In order to shorten C, the width of each winding body of the coil 114a of the first layer and the coil 117a of the second layer (hereinafter, simply referred to as a thin film coil unless otherwise specified) is reduced, or each coil is wound. It is necessary to narrow the body distance. However, in the conventional thin film magnetic head, it has been difficult to make the winding body width or the winding body spacing of the thin film coil narrower than the current one because of the following reasons.

First, since it is necessary to reduce the electric resistance of the thin-film coil, there is a natural limitation on reducing the width of the winding body. Even if copper having a high conductivity is used to reduce the resistance value of the thin film coil, a height of about 2 to 3 μm is necessary to secure the cross-sectional area of the thin film coil. Forming the width as narrow as 1.5 μm or less is a problem in terms of shape stability. Therefore, it is difficult to make the winding width of the thin film coil narrower than this.

On the other hand, it has been difficult to narrow the winding interval of the thin film coil for the following two reasons.

The first reason is as follows. That is,
Conventionally, the thin film coil is formed by the electroplating method as described with reference to FIG. 30. At this time, in order to uniformly deposit copper on the entire wafer in the opening 113 formed in the photoresist 112. Then, the thin seed layer 111 is formed in advance. Therefore, the coiled body 114 is formed in the opening 113 by electroplating.
After forming the wire, an opening 1 is provided to separate the winding bodies.
The seed layer 111 in 13 needs to be selectively removed. The removal of the seed layer 111 is performed by ion milling using, for example, argon with the coiled body 114 as a mask, as described with reference to FIG. Here, ion milling is basically recommended to be performed in a direction substantially perpendicular to the substrate surface. However, in this case, redeposition of etched copper occurs and the thin film coil is wound between the winding bodies. Is likely to cause insulation failure. Therefore, in order to avoid such an inconvenience, it is necessary to perform ion milling while maintaining a certain angle with respect to the vertical line of the substrate. Generally, if ion milling is performed at a large angle of, for example, 40 to 45 degrees, reattachment of the etching material hardly occurs. However, when ion milling is performed at such a large angle, the coiled body 1
The shadowed area of 14 is not sufficiently irradiated with ions, and the aperture 1
The seed layer 111 in 13 remains largely left. Therefore, as described with reference to FIG. 32, ion milling is generally performed at an angle of 5 to 10 degrees. However, when it is attempted to further reduce the spacing between the windings of the thin-film coil, even if the angle is as small as 5 to 10 degrees, the shadow portion of the coil-shaped body 114 is not sufficiently irradiated with ions, and the seed layer 111 is not formed. It partially remains and causes a short circuit between winding bodies. When ion milling is performed at an angle of 5 to 10 degrees or less, as described above, redeposition of the etching material also causes a short circuit between the winding bodies. Therefore, the winding interval of the thin film coil should be 2
It was difficult to set the thickness to 3 μm or less.

The second reason is as follows. That is,
As shown in FIG. 29, in order to narrow the winding body interval of the coil-shaped body 114 to 1 μm or less, the photoresist 11 is used.
The line width (wall thickness) of the spiral pattern 2 needs to be narrowed (thinned). On the other hand, as described above, in order to set the height of the thin film coil to 2 to 3 μm, it is necessary to set the depth of the opening 113, that is, the film thickness of the photoresist 112 to 3 to 4 μm. However, when the thin film coil is formed by the electroplating method as described with reference to FIG. 30, it is necessary to stir the electrolytic plating solution such as copper sulfate in order to ensure the uniformity of the formed film thickness. Therefore, the coiled body 114
If the line width (wall thickness) of the spiral pattern of the photoresist 112 is made too thin in order to narrow the winding body spacing of
The thin wall collapses due to the agitation of the electrolytic plating solution, and the thin film coil cannot be formed accurately. Therefore, it is difficult to reduce the winding interval of the thin film coil.

From the above, it is not easy to make the winding body width and the winding body space of the thin-film coil narrower than the current situation, and as a result, it is difficult to shorten the coil bundle width LC.

In order to improve the NLTS characteristics of the recording head, it is possible to increase the number of coil windings of the thin film coil. However, in order to increase the number of coil windings without increasing the coil bundle width LC and without reducing the winding body width and the winding body interval of the thin film coil,
It is necessary to increase the number of thin film coil layers to four or five. However, when the number of thin film coil layers is increased, the apex angle θ described above becomes large, and it becomes impossible to achieve a narrow track width (narrowing of the magnetic pole width P2W in FIG. 34). In order to keep the apex angle within a predetermined range, it is desirable that the number of thin-film coil layers is 3 or less, preferably 2 or less, but this cannot increase the number of coil windings, and in the end, , NLTS
It is difficult to improve the characteristics.

In order to solve such a problem, the present applicant has made insulation so as to cover at least the bottom surface and the side surface of the spiral groove which is the interwinding region of the first thin film coil formed in a spiral shape. A thin film magnetic head in which a film is formed and a second thin film coil is embedded and formed in at least the inside of a spiral groove covered with the insulating film so as to be in direct contact with the insulating film, and a manufacturing method thereof. is suggesting. According to the thin film magnetic head and the manufacturing method thereof,
Since the first thin film coil and the second thin film coil forming the thin film coil section belong to the same layer through the insulating film, the winding body width and the winding body spacing of each thin film coil are set to be smaller than the current one. It is possible to reduce the winding body pitch per single layer of the thin-film coil portion without making it particularly narrow.
Therefore, as a result of being able to shorten the coil bundle width LC, it is possible to shorten the magnetic path length LM.

Further, as a specific example of the method of manufacturing the thin film magnetic head, the applicant of the present invention proposes to form the second thin film coil by an electroplating method which does not require much equipment cost. Specifically, a thin conductive film is formed so as to cover the insulating film, and the conductive film is used as a seed layer to carry out plating growth by electroplating, thereby forming a spiral groove covered with the insulating film. It is proposed to bury the inside with a conductive layer that will become the second thin film coil.

However, as described above, when the second thin film coil is to be formed by the electroplating method, not only the seed layer formed at the bottom of the spiral groove,
The plating growth also progresses from the seed layer formed on the side surface of the spiral groove. At this time, in general, since the plating growth rate from the side surface of the groove is faster than the plating growth rate from the bottom of the groove, a key hole is formed inside the narrow spiral groove.
A void called "void" may occur. In the electroplating method, for example, when copper (Cu) is grown by plating, copper sulfate is usually used as a plating solution (electrolytic solution). However, as described above, when a void is generated inside the spiral groove, The plating solution will remain in the void portion. This residual plating solution may cause the thin film coil to corrode and break after the thin film magnetic head is manufactured.

The present invention has been made in view of the above problems, and an object thereof is to improve various characteristics by shortening the magnetic path length by narrowing the width of the coil bundle, and at the same time, to reduce voids in the manufacturing process. It is an object of the present invention to provide a thin film magnetic head capable of suppressing the occurrence and preventing the coil breakage due to a change over time, and a manufacturing method thereof.

[0035]

The thin-film magnetic head of the present invention has at least two magnetic poles that are magnetically coupled and have two magnetic poles that are partially opposed to the recording medium and face each other via a gap layer. A thin film magnetic head having a layer and a thin film coil portion disposed between the at least two magnetic layers or another magnetic layer connected to the magnetic layer, wherein the thin film coil portion is formed in a spiral shape. A first thin film coil,
An insulating film formed to cover at least the bottom surface and side surfaces of the spiral groove that is the interwinding region of the first thin-film coil, and to cover at least the bottom surface and side surfaces of the spiral groove covered by this insulating film. A conductive film formed on the insulating film, an insulating film sidewall formed to cover only the conductive film on the side surface of the spiral groove of the conductive film, and at least the conductive film and the spiral groove covered by the insulating film sidewall. And a second thin film coil formed so as to fill the inside.

In the thin film magnetic head of the present invention, the second thin film coil formed so as to fill at least the inside of the spiral groove, which is the interwinding region of the first thin film coil,
The insulating film insulates and separates from the first thin film coil.
With this structure, the first thin-film coil and the second thin-film coil belong to the same layer through the insulating film, and the winding body pitch per single layer in the thin-film coil portion is reduced. Further, the insulating film in the spiral groove is covered with the conductive film having a predetermined function, but the conductive film on the side surface portion of the spiral groove is covered with the insulating film side wall, so that the function is suppressed. .

Further, in the thin film magnetic head of the present invention, it is possible that the above conductive film functions as a base conductive film used when forming the second thin film coil, for example. Specifically, it is possible that the conductive film functions as a seed layer for growing the second thin film coil, for example. In this case, the insulating film side wall plays a role of preventing the second thin-film coil from growing and forming by using the conductive film on the side surface of the spiral groove as a seed layer, and the conductive film exposed on the bottom surface of the spiral groove is fulfilled. It is possible to form the second thin-film coil by, for example, plating growth using only the film as a seed layer.

In the thin film magnetic head of the present invention, the insulating film may be formed so as to reach the top of the first thin film coil. In this case,
The second thin film coil may be formed so as to cover a part of the top portion of the first thin film coil via the insulating film.

Further, in the thin-film magnetic head of the present invention, the above-mentioned thin-film coil portion is further formed as a layer separate from the first thin-film coil and the second thin-film coil via the interlayer insulating film, and the first thin-film coil portion is formed. A third thin film coil for connecting between the inner peripheral end of the thin film coil and the outer peripheral end of the second thin film coil or between the outer peripheral end of the first thin film coil and the inner peripheral end of the second thin film coil. It may be included.

In the thin film magnetic head of the present invention, the first
The thin film coil may include a thin underlying conductive film and a conductive plating layer formed using the underlying conductive film as a seed layer.

In the thin film magnetic head of the present invention, the insulating film may be an inorganic insulating film. In this case, aluminum oxide can be used as the inorganic insulating film.

In the thin film magnetic head of the present invention, the side wall of the insulating film may be an inorganic insulating film. In this case, aluminum oxide can be used as the inorganic insulating film.

Further, in the thin film magnetic head of the present invention, the insulating film has a spiral shape even when it covers at least the bottom surface and the side surface of the spiral groove which is the interwinding region of the first thin film coil. It is preferable to form the film so that the groove shape corresponding to the groove can remain.

Further, in the thin film magnetic head of the present invention, a plurality of thin film coil portions may be formed hierarchically with the interlayer insulating film interposed therebetween.

Further, the thin film magnetic head of the present invention may further have a magnetoresistive element for reading.

A method of manufacturing a thin-film magnetic head according to the present invention comprises at least two magnetic layers which are magnetically coupled and have two magnetic poles which are partially opposed to a recording medium and face each other via a gap layer. A method of manufacturing a thin film magnetic head having the thin film coil portion disposed between at least two magnetic layers or another magnetic layer connected to the at least two magnetic layers, wherein the forming step of the thin film coil portion is spiral. Of forming the first thin-film coil, a step of forming an insulating film so as to cover at least the bottom surface and the side surface of the spiral groove that is the interwinding region of the first thin-film coil, and the step of covering with the insulating film. Forming a conductive film so as to cover at least the bottom surface and side surfaces of the spiral groove; forming an insulating film sidewall so as to cover only the conductive film on the side surface portion of the spiral groove of the conductive film; Membrane and Absence It is obtained as a step of forming a second thin film coil so as to fill at least internal covered spiral groove by the membrane sidewalls.

In the method of manufacturing a thin film magnetic head according to the present invention, the above conductive film may function as a base conductive film used when forming the second thin film coil, for example. is there. Specifically, the conductive film may function as a seed layer for growing the second thin film coil. In this case, the insulating film side wall plays a role of preventing the second thin-film coil from growing and forming by using the conductive film on the side surface of the spiral groove as a seed layer, and the conductive film exposed on the bottom surface of the spiral groove is fulfilled. It is possible to form the second thin-film coil by, for example, plating growth using only the film as a seed layer.

In the method of manufacturing a thin film magnetic head according to the present invention, the insulating film may reach the top of the first thin film coil. In this case, the second thin film coil can cover a part of the top of the first thin film coil through the insulating film.

Further, in the method of manufacturing a thin film magnetic head according to the present invention, further, between the inner peripheral end of the first thin film coil and the outer peripheral end of the second thin film coil or the outer peripheral end of the first thin film coil. A step of forming a third thin-film coil for connecting between the inner peripheral end of the second thin-film coil and the first thin-film coil and the second thin-film coil via an interlayer insulating film. May be included.

Further, in the method of manufacturing a thin film magnetic head according to the present invention, the step of forming the first thin film coil includes the step of forming a thin underlying conductive film and selective plating growth using the underlying conductive film as a seed layer. You may make it include the process made to perform.

Further, in the method of manufacturing a thin film magnetic head according to the present invention, the above insulating film may be an inorganic insulating film. In this case, aluminum oxide can be used as the inorganic insulating film.

In the method of manufacturing a thin film magnetic head according to the present invention, the side wall of the insulating film may be an inorganic insulating film. In this case, aluminum oxide can be used as the inorganic insulating film.

Further, in the method of manufacturing a thin film magnetic head according to the present invention, the insulating film also covers at least the bottom surface and the side surface of the spiral groove which is the interwinding region of the first thin film coil. It is preferable that the spiral groove has a film thickness such that the groove shape corresponding to the spiral groove can remain.

Further, in the method of manufacturing a thin film magnetic head according to the present invention, a plurality of thin film coil portions may be formed hierarchically with the interlayer insulating film interposed therebetween.

The method of manufacturing a thin film magnetic head according to the present invention may further include a step of forming a magnetoresistive element for reading.

[0056]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

1 to 14 show respective manufacturing steps of a composite type thin film magnetic head as a method of manufacturing a thin film magnetic head according to an embodiment of the present invention. In these figures, (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. The thin-film magnetic head according to the embodiment of the present invention is embodied by the method of manufacturing the thin-film magnetic head according to the present embodiment, and therefore will also be described below.

In the manufacturing method according to the present embodiment, as shown in FIG. 1, first, for example, AlTiC (Al ₂ O ₃
On a substrate 1 made of TiC, for example, alumina (Al ₂
The insulating layer 2 made of O ₃ ; aluminum oxide) is about 5 μm.
Deposit with a thickness of about m. Next, as shown in FIG.
About 2% of permalloy (NiFe) is formed on the insulating layer 2 by a plating method using a photoresist film (not shown) as a mask.
The lower shield layer 3 for the reproducing head is formed by selectively forming it with a thickness of ˜3 μm.

Next, as shown in FIG. 3, for example, alumina is sputter deposited to a thickness of 100 to 200 nm on the lower shield layer 3 to form a shield gap film 4.
Next, the MR film 5 for forming the MR element for reproduction is formed on the shield gap film 4 to have a thickness of about several tens nm, and is formed into a desired shape by high-precision photolithography.
Next, the shield gap film 6 is formed on the shield gap film 4 and the MR film 5, and the MR film 5 is embedded in the shield gap films 4 and 6. Although not shown,
A pair of lead layers for electrically connecting to the MR film 5 are also selectively formed. Here, the MR film 5 corresponds to the "readout magnetoresistive element" in the present invention.

Next, as shown in FIG. 4, an upper shield / lower magnetic pole (hereinafter referred to as lower magnetic pole) 7 made of permalloy or the like is formed on the shield gap film 6 by, for example, a plating method in a range of about 3 to 3. It is selectively formed with a thickness of 4 μm.
Here, the lower magnetic pole 7 is the "two magnetic layers" in the present invention.
Corresponding to one of the.

Next, an inorganic insulating film, for example, a silicon oxide film (SiO ₂ ) having a thickness of about 1 to ₂ μm is formed on the lower magnetic pole 7, taper etching is performed, and selective patterning is performed. The insulating layer 8 for defining the apex angle and the throat height is formed. The etching at this time is performed by dry etching, particularly RIE (reactive ion etching). In this case, for example, BCl ₃ (boron trichloride), Cl ₂ (chlorine), CF
It is desirable to perform the RIE method using a gas such as ₄ (carbon tetrafluoride) or SF ₆ (sulfur hexafluoride).
The insulating layer 8 is not limited to the silicon oxide film, but may be an alumina film or another inorganic insulating film such as a silicon nitride film (SiN). Furthermore, a photoresist layer may be used as the insulating layer 8.

Next, as shown in FIG. 5, the recording gap layer 9 made of a non-magnetic material such as alumina or aluminum nitride is formed so as to cover the insulating layer 8 and the bottom pole 7.
Is formed to a film thickness of about 100 to 300 nm, and then an opening 20 is formed in a region (the right side region in FIG. 5) connecting the lower magnetic pole 7 and an upper magnetic pole described later.

Next, as shown in the figure, a magnetic layer made of, for example, permalloy or the like is formed to a thickness of about 3 to 4 μm, and then this is patterned by etching,
The top pole pieces 10a and 10b are formed. At this time, the upper magnetic pole piece 10a is formed so as to extend from the side to be the air bearing surface to one portion of the insulating layer 8 on the air bearing surface side through one tapered portion of the insulating layer 8.
0b is formed so as to cover the opening 20 of the recording gap layer 9 and extend to a part of the insulating layer 8 on the side not on the air bearing surface through the other tapered portion of the insulating layer 8. As a result, the upper magnetic pole piece 10b comes into contact with the lower magnetic pole 7 through the opening 20 of the recording gap layer 9 and is magnetically coupled.

Next, as shown in FIG. 5B, the recording gap layer 9 and the lower magnetic pole 7 are etched by about 0.5 μm using the upper magnetic pole piece 10a as a mask to form a trim structure.

Next, as shown in FIG. 6, a thin seed layer 11 made of, for example, copper and having a thickness of about 50 to 100 nm is formed on the entire surface by sputtering or the like, and then a process using a photolithography method similar to the conventional one is used. Copper is selectively formed on the seed layer 11 by electroplating to form the coiled body 12. Here, the seed layer 11
Corresponds to the “underlying conductive film” in the present invention (claims 8 and 23), and the coiled body 12 corresponds to the “conductive plating layer” in the present invention.

More specifically, 3.0 to 3.0 on the seed layer 11.
A thick photoresist (not shown) of 4.0 μm is formed, and a spiral opening (not shown) reaching the seed layer 11 is formed in the photoresist by photolithography. The depth of this opening is equal to the film thickness of the photoresist, and the width of the opening is about 1.5 to 2.0 μm. The width of the spiral photoresist pattern defined by the opening is about 1.5 to 2.5 μm. Next, using such a photoresist pattern as a mask, electroplating of copper is performed using a plating solution of copper sulfate to form a first coil in the opening of the photoresist. To form. As a result, the winding body width of the coiled body 12 is about 1.5 to 2.0 μm, and the winding body spacing is about 1.5 to 2.5 μm. In addition, the coiled body 12
Is less than the depth of the photoresist opening,
For example, it is set to 2.5 to 3.0 μm.

In this case, the pattern width of the photoresist used for selective electroplating (here, 1.5 to 2.5 μm).
m) is relatively large, about 1/2 of the film thickness (here, 3.0 to 4.0 μm), and the shape is stable. Therefore, even if the plating solution is stirred in the electroplating process, the photoresist is Is unlikely to collapse.

Next, after the photoresist used for the selective electroplating is removed, as shown in FIG. 7, ion milling is performed by, for example, an argon ion beam IB, so that the coil body 12 is wound between the winding bodies. The seed layer 11 at the bottom of the (recess) is removed, and the winding bodies of the coiled body 12 are separated from each other to form the first coil 12a. This ion milling is performed at an angle of 5 to 10 degrees, for example.
In this way, when ion milling is performed at an angle close to vertical,
Although the material forming the seed layer 11 may be scattered and redeposited by the impact of the ion beam, in the present embodiment, as described above, the winding body interval of the coiled body 12 is 1.
Since it is relatively large, about 5 to 2.5 μm, there is little risk of short-circuiting between the winding bodies due to redeposition of the scattered seed layer constituent material, and complete separation is possible.
Moreover, since the winding body interval of the coiled body 12 is large,
The angle of ion milling is the angle described above (5 to 10 degrees)
Even with the above, the seed layer 11 will not be partially left because the ions are sufficiently irradiated even to the shadowed portion of the coiled body 12. Here, the first coil 12
“A” corresponds to the “first thin film coil” in the present invention.

Next, as shown in FIG. 8, an insulating film 13 made of, for example, alumina and having a thickness of about 300 to 500 nm is formed so as to cover the uneven shape after the first coil 12a is formed. After being formed on the entire surface, the insulating film 13 is further covered to have a thickness of about 5 made of copper, for example.
A thin seed layer 31 having a thickness of 0 to 70 nm is formed on the entire surface by sputtering or the like. However, the insulating film 13 may be formed using an inorganic insulating film such as a silicon oxide film or an alumina nitride film other than alumina. Here, the insulating film 13
Is a first coil 12a and a second coil 14a described later.
To insulate and separate, and corresponds to the "insulating film" in the present invention. The seed layer 31 corresponds to the "conductive film" in the present invention.

Next, as shown in FIG.
And a thickness of about 10 made of alumina, for example.
The insulating film 32 having a thickness of about 0 to 300 nm is formed. The insulating film 32 may be formed using an inorganic insulating film such as a silicon oxide film or an alumina nitride film, or an organic insulating film such as a photoresist film other than alumina.

Next, as shown in FIG. 9, for example, RIE
The insulating film 32 is etched by an anisotropic etching method such as the above, and the spiral groove 22a covered with the seed layer 31 is etched.
An insulating film side wall 32a is formed on the side surface of the. At this time, the insulating film 32 is removed and the seed layer 31 is exposed on the bottom of the spiral groove 22a and on the spiral ridge 22b. As shown in FIG. 9B, the side wall of the trim structure including the upper magnetic pole piece 10 a, the write gap layer 9 and a part of the lower magnetic pole 7 is also provided with the insulating film sidewall 32 through the seed layer 31.
b is formed.

Then, as shown in FIG. 10, a photoresist layer 33 is selectively formed in a region other than the region where the first coil 12a is formed, and copper sulfate is used as a mask with the photoresist layer 33 as a mask. Selective electroplating treatment for performing plating growth based on the seed layer 31 in a plating solution such as the above, and a thickness of about 2.0 to 3.0 μm made of copper is formed in the region where the first coil 12a is formed. The plating layer 14 is formed. At this time, due to the presence of the insulating film side wall 32a covering the side surface of the spiral groove 22a, plating growth from the seed layer 31 on the side surface of the groove is blocked, and the seed layer 31 exposed at the bottom of the spiral groove 22a is prevented. Only the plating growth of is allowed. Therefore, generation of voids inside the plating layer 14 formed so as to be embedded inside the spiral groove 22a is suppressed, and the inside of the spiral groove 22a is completely filled with the plating layer 14. Here, the insulating film sidewall 32a is a feature that corresponds to the "insulating film sidewall" according to this invention.

Next, as shown in FIG. 11, an insulating layer 3 made of, for example, alumina is formed on the entire surface for flattening the surface.
5 is formed to a thickness of about 3.0 to 5.0 μm.

Next, as shown in FIG. 12, for example, CM
A P (chemical mechanical polishing) method is used to polish the entire surface by a predetermined amount. The polishing amount at this time is, as shown in the figure, the insulating film 13 and the seed layer 31 on the winding body of the first coil 12a, and a part of the insulating film 1 on the upper pole pieces 10a and 10b.
3 and the seed layer 31 are removed to remove the first coil 12
It is assumed that the winding body of a and the upper surfaces of the top pole pieces 10a and 10b are partially exposed. Thereby, the plating layer 14
Are separated from each other between the spiral grooves 22a of the first coil 12a, and the second coil 14a is formed so as to fill the inside of the spiral groove 22a. This second coil 14
The a is insulated from the first coil 12a by the insulating film 13. Here, the second coil 14a corresponds to the "second thin film coil" in the present invention.

Next, as shown in FIG. 13, by the photolithography method, 2.0 to 3.0 is formed in the region of the thin film coil portion including the first coil 12a and the second coil 14a.
After selectively forming a photoresist layer 16 having a film thickness of about μm, an upper magnetic pole 1 having a thickness of about 3.0 to 4.0 μm made of permalloy or the like is formed thereon by, for example, a plating method.
7 is selectively formed. The upper magnetic pole 17 is formed of the insulating layer 8
While contacting and magnetically connecting to the upper magnetic pole piece 10a in the front end region, the contacting and magnetically connecting to the upper magnetic pole piece 10b in the rear end region of the insulating layer 8. Thus, the upper magnetic pole piece 10a, the upper magnetic pole 17, the upper magnetic pole piece 10
A magnetic path is formed by b and the lower magnetic pole 7. Here, the top pole piece 10a corresponds to the other of the "two magnetic layers" in the present invention, and the top pole 17 corresponds to the "other magnetic layer" in the present invention.

Next, as shown in FIG. 14, an overcoat layer 18 made of alumina, for example, is formed to a thickness of about 20 to 40 μm so as to cover the entire surface. Finally,
The slider is machined to form the air bearing surfaces of the recording head and the reproducing head, and the composite type thin film magnetic head is completed.

FIG. 15 is a plan view of a composite type thin film magnetic head manufactured by the manufacturing method according to this embodiment. In this figure, only the main layers are shown, and the overcoat layer 18 and other layers are omitted. In this figure, the symbol TH represents the throat height defined by the edge of the insulating layer 8 on the air bearing surface side. The lower magnetic pole 7 and the upper magnetic pole 17 are connected via an opening 20 (see FIG. 5) formed in the recording gap layer 9 (not shown in the drawing).

FIG. 16 is a diagrammatically simplified representation of the winding direction of the first coil 12a and the second coil 14a and the manner of connection. In the actual thin film magnetic head, these coils 12a and 14a are formed so as to surround the portion (the opening 20 shown in FIG. 13) that connects the lower magnetic pole 7 and the upper magnetic pole 17, but Illustration of parts is omitted. As shown in this figure, the first coil 12a and the second coil 14a are formed so as to be combined with each other. The winding direction of each coil is always the same with reference to the direction in which the winding radius of the winding body of each coil decreases, but this winding direction is called right winding here. .

In FIG. 16, the contact pad P1 formed at the outer end of the first coil 12a is connected to the first external terminal (not shown) by a lead (not shown).
The contact pad P2 formed at the inner end of the first coil 12a includes the first coil 12a and the second coil 14a.
It is connected to a contact pad P3 formed at the outer end of the second coil 14a by a linear relay lead 21 selectively formed in a different layer. This second coil 1
The contact pad P4 formed at the inner end of 4a is connected to the second external terminal (not shown) by another lead not shown. That is, the first coil 12a and the second coil
The coils 14a are connected in series via the relay lead 21 so that they are both right-handed. Then, by applying a voltage between the above-mentioned first and second external terminals, it is possible to cause a current to flow in the same direction through the first coil 12a and the second coil 14a. As a result, magnetic flux is generated in the magnetic path formed by the upper magnetic pole piece 10a, the upper magnetic pole 17, the upper magnetic pole piece 10b, and the lower magnetic pole 7, and the upper magnetic pole piece 10a and the lower magnetic pole 7 that face each other with the recording gap layer 9 in between.
Magnetic recording is performed on a recording medium (not shown) by the magnetic flux generated between and.

As described above, according to the present embodiment, when the plating layer 14 is formed by plating growth inside the spiral groove 22a of the first coil 12a, the inner surface of the spiral groove 22a is formed. Since the seed layer 31 of the groove side surface portion of the formed seed layer 31 as the plating base is covered by the insulating film side wall 32a, the plating growth from the groove side surface portion can be prevented, and the spiral groove 22a can be prevented. It is possible to suppress the generation of voids when the inside of the substrate is filled with the plating layer 14. As a result, the second coil 14a obtained by separating the plated layer 14 between the spiral grooves 22a is obtained.
It is possible to effectively prevent the occurrence of corrosion over time. Therefore, it is possible to obtain a highly reliable thin film magnetic head that can withstand long-term use.

Further, the seed layer 31 and the insulating film side wall 32.
spiral groove 22 of the first coil 12a covered by a
Since the second coil 14a is embedded in the inside of a, it is possible to reduce the winding body pitch of the thin-film coil without particularly improving the processing accuracy in the forming process of the first coil 12a. Become. However, the “winding body pitch of the thin-film coil” here means a winding body pitch when focusing on a single layer, that is, a winding body pitch per single layer. That is, in the related art, as shown in FIG. 34, in order to increase the number of turns of the thin film coil, the first layer coil 114a and the second layer coil 117a are formed as separate layers. However, if you try to form this as a single hierarchy,
Since the coil 117a of the first layer is arranged in the lateral direction of the coil 114a of the first layer, the coil bundle width LC becomes considerably long, and as a result, the magnetic path length LM also becomes long. In this case, the winding body pitch per single layer is
As shown in FIG. 34, the coil pitch C of the first layer coil 114a or the second layer coil 117a itself is C.
It is P1. On the other hand, in the present embodiment, as shown in FIG. 14, the second coil 14a is replaced by the first coil 1a.
Since it is formed so as to be embedded inside the spiral groove 22a of 2a, the above-mentioned "winding body pitch of the thin film coil", that is, both the first coil 12a and the second coil 14a are included. The winding body pitch CP2 per single layer of the thin film coil is about one half of the winding body pitch CP1 per single layer of the conventional (FIG. 34). Therefore, without increasing the number of layers of the thin-film coil, and the coil bundle width LC
It is possible to increase the number of turns of the winding body without increasing the number of turns. In other words, under the condition that the number of layers of the thin-film coil and the number of windings of the winding body are the same, the first coil 1
It is possible to further reduce the coil bundle width LC without reducing the distance between the winding bodies of the second coil 14a and the second coil 14a itself. The reduction of the coil bundle width LC means that the magnetic path length LM can be reduced, and as a result, the magnetic flux rising time of the recording head and the non-linear transition shift (NLT).
It is possible to improve S) characteristics and overwriting characteristics. Further, it is possible to reduce the size of the thin film magnetic head itself by reducing the magnetic path length LM. Further, under the condition that the number of windings of the winding body and the coil bundle width LC are the same, the number of layers of the thin film coil can be further reduced, so that the apex angle θ can be further reduced. Therefore, it is possible to prevent the effective track width from increasing due to the spread of the magnetic flux generated when writing the narrow track.

Further, in the present embodiment, as described with reference to FIG. 6, since the winding body spacing of the first coil 12a may be increased, the photoresist pattern used for selective plating can be easily processed. Moreover, since the ratio of the resist width to the resist height in the photoresist pattern can be increased, the photoresist pattern is less likely to collapse in the electroplating solution. Further, since the winding body interval of the first coil 12a can be made large, when the seed layer between the winding bodies is removed by ion milling after film formation by electroplating, the irradiation angle of the ion beam is made relatively large. Therefore, it is less likely that a seed layer portion that cannot be removed is formed behind the winding body and that the seed layer material scattered by the ion milling is less likely to be redeposited. Therefore, it is possible to avoid the occurrence of a short circuit between the winding bodies of the first coil 12a.

In the conventional thin film magnetic head,
As shown in FIG. 34, the throat height TH is defined by the photoresist 110. The photoresist 110 has the seed layer 111 as shown in FIG.
When the film was removed by etching, its front end edge (the left end in FIG. 32) was set back, and the throat height exactly as designed could not be obtained in the completed thin film magnetic head. On the other hand, in this embodiment, since the insulating layer 8 that defines the throat height is formed of the inorganic insulating film, the position of the edge of the insulating layer 8 during the etching of the seed layer 11 shown in FIG. No fluctuation (pattern shift) occurs. Therefore, the throat height can be accurately controlled. Further, it is possible to accurately control the MR height and the apex angle.

In this way, according to the present embodiment,
With high reliability that can withstand long-term use,
It is possible to manufacture a high-performance thin film magnetic head in which the magnetic pole width, the throat height, the MR height, and the apex angle are accurately controlled and a narrow track can be realized.

In this embodiment, as shown in FIG. 14, the seed layer 31 is formed on the top pole pieces 10a and 10b.
However, as shown in FIG. 17, the seed layer 31 may not be left on the top pole pieces 10a and 10b. For that purpose, in FIG. 8, after the seed layer 31 is formed, the seed layer 31 on the upper magnetic pole pieces 10a and 10b is selectively removed by photolithography, and then the insulating film side wall 32a is formed. Good. By doing so, it is possible to eliminate the possibility that the seed layer 31 is exposed on the polishing surface during the polishing process for forming the air bearing surface, which may cause recesses (recesses) on the air bearing surface. .

Further, in the present embodiment, the first coil 1
Although the single-layer thin-film coil portion including the second coil 14a and the second coil 14a is formed, the present invention is not limited to this. For example, as shown in FIG. You may make it form the thin film coil of another hierarchy which consists of the coil 24 and the 4th coil 28.
In this case, the steps of forming the third and fourth coils 24, 28 are the same as those of the first and second coils 12a, 14 respectively.
This is similar to the step of forming a. In this case, the photoresist layer 16 is selectively formed on the thin-film coil portion formed of the first and second coils 12a and 14a, and then,
The third and fourth coils 24 and 28 forming the second layer thin film coil portion are sequentially formed. Upper magnetic pole pieces 17a and 17c, which are magnetically connected to the upper magnetic pole pieces 10a and 10b, are selectively formed before and after the thin film coil portion in the second layer. Further, the insulating layer 18a is formed on the second layer portion above the upper pole piece 10a. Next, the third
And a photoresist layer 25 is selectively formed so as to cover the thin film coil portion including the fourth coils 24 and 28, and the upper magnetic pole 17b magnetically coupled to the upper magnetic pole pieces 17a and 17c is further formed thereon. Selectively formed. Finally, the overcoat layer 18b is formed. Note that FIG.
In the present invention, the photoresist layer 16 is used in the present invention (claim 14).
And corresponds to the "interlayer insulating film" in claim 29).

In this modification, as shown in FIG. 19, the contact pad P1 formed at the outer end of the first coil 12a.
Is connected to a first external terminal (not shown), and
The contact pad P2 at the inner end of the coil 12a and the contact pad P2 'at the inner end of the third coil 24 are connected.
Further, the contact pad P on the outer end of the third coil 24
3'and the contact pad P3 at the outer end of the second coil 14a are connected, and the contact pad P4 at the inner end of the second coil 14a is connected to the contact pad P4 'at the inner end of the fourth coil 28a. Connecting. The contact pad P5 at the outer end of the fourth coil 28 is connected to a second external terminal (not shown). Note that FIG. 19A shows the winding direction and connection mode of the first coil 12a and the second coil 14a, and FIG. 19B shows the winding direction of the third coil 24 and the fourth coil 28. And a connection mode are diagrammatically simplified. As shown in these figures,
Coil 12a, third coil 24, second coil 14
The a and the fourth coil 28 are connected in series in this order, and the winding directions are all right-handed. Therefore, by applying a voltage between the above-mentioned first and second external terminals, it is possible to flow a current in these coils in the same winding direction. More specifically, P1-P2-
The current flows in the order of P2'-P3'-P3-P4-P4'-P5 or vice versa. Therefore, under the condition that the coil bundle widths LC are equal, the number of turns of the thin film coil can be further increased as compared with the case of the above-described embodiment (FIG. 14). On the contrary, under the condition that the number of turns of the thin film coil is equal, the coil bundle width LC can be further shortened.

FIG. 20 shows a comparison between the magnetic path lengths of the conventional thin film magnetic head and the thin film magnetic head according to the embodiment of the present invention. (A) of this figure is shown in FIG.
4 is a plan view of the conventional thin film magnetic head shown in FIG.
18B shows a planar configuration of the thin film magnetic head according to the embodiment of the invention shown in FIG. Each of these thin film heads is formed as a two-layer structure as shown in FIGS. 34 and 18, and the winding body spacing of each coil is formed to be approximately the same, but two layers. In the embodiment of the present invention, the winding body pitch CP of the thin-film coil in the case of considering all the coils for one minute is reduced to half or less of the conventional one. Therefore, the magnetic path length LM2 of the thin film magnetic head according to the embodiment of the invention (see FIG. 20).
(B)) is reduced to about two-thirds of the magnetic path length LM1 of the conventional thin film magnetic head ((a) in the same figure), which allows the thin film magnetic head according to the embodiment of the present invention. Then
Various characteristics such as magnetic flux rising time, NLTS, and overwriting characteristics are further improved as compared with the conventional one.

In the embodiment shown in FIG. 14, the second coil 14a is embedded in the spiral groove 22a of the first coil 12a without any excess or deficiency. In addition, as shown in FIG. 23, for example, the second coil 14a is connected to the spiral groove 22a of the first coil 12a.
Not only inside but also in the spiral coil 22 of the first coil 12a
It may be formed so as to reach even a part on b, and its cross-sectional shape may be T-shaped. The manufacturing process in this case is as follows, for example.

That is, after forming the insulating film side wall 32a in the step shown in FIG. 9 described above, as shown in FIG. 21, the upper magnetic pole piece 10 is formed by photolithography.
A photoresist layer 33 is formed on a and 10b, and a spiral photoresist pattern 15 is also formed on the winding body of the first coil 12a. The line width of the photoresist pattern 15 is the winding body of the first coil 12a, the insulating film 13, the seed layer 31, and the insulating film sidewall 32a.
The width is smaller than the width of the spiral ridge 22b. Next, using the photoresist layer 33 and the photoresist pattern 15 as a mask, the plating layer 14 'is selectively grown using the seed layer 31 at the bottom of the spiral groove 22a as a seed. At this time, the upper surface of the plating layer 14 ′ has a spiral root 2
It should be higher than the upper surface of 2b. Next, as shown in FIG. 22, the photoresist layer 33 and the photoresist pattern 15 are removed, and then ion milling or sputter etching is performed on the top pole pieces 10a and 10b and in the spiral shape using the plating layer 14 'as a mask. The seed layer 31 exposed on the ridges 22b is removed to separate the plating layers 14 'from each other. As a result, from the inside of the spiral groove 22a of the first coil 12a to the spiral crest 22b.
The second coil 1 having a T-shaped cross-sectional shape toward the top
4a 'is formed. The subsequent steps are the same as those described with reference to FIG. 14 described above. As shown in FIG. 23, the photoresist layer 16 is formed on the thin film coil portion including the first coil 12a and the second coil 14a ′. After being selectively formed, an upper magnetic pole 17 which is in contact with the upper magnetic pole pieces 10a and 10b and magnetically connected thereto is selectively formed thereon,
Further, the overcoat layer 18 is formed so as to cover the entire surface.
To form.

According to this modification, the second coil 14
Since a ′ reaches not only the inside of the spiral groove 22a of the first coil 12a but also a part of the spiral crest 22b and its cross-sectional shape is T-shaped, The cross-sectional area of the coil 14a 'can be increased, and the electric resistance of the thin film coil portion as a whole can be reduced.

In the example shown in FIG. 23, the first coil 12
Although the thin film coil portion is constituted by the a-shaped and T-shaped second coil 14a ', as shown in FIG. 24, the winding body gap of the second coil 14a' (that is, the first coil 14a '). Spiral ridge 22b composed of winding body of coil 12a
The T-shaped third coil 39 may be formed by utilizing the spiral groove 38 which is the upper space). The step of forming the third coil 39 is similar to the step of forming the second coil 14a ', and the insulating film and the seed layer are formed so as to cover the uneven shape after the formation of the second coil 14a'. After that, an insulating film side wall is formed on the inner side surface of the spiral groove 38, and then a seed layer at the bottom of the spiral groove 38 is grown by a plating method to form a third coil 39. Here, the third coil 39 corresponds to the “third thin-film coil” in the present invention (claims 7 and 22).

Further, although not shown, the third coil 3
It is also possible to form the fourth coil using the winding wire gap of 9. Hereinafter, it is possible to form the odd-numbered coils and the even-numbered coils alternately in the same manner. By doing so, all the coils after the second coil 14a 'can be formed in a T-shaped cross-sectional shape, a large cross-sectional area of the coil is ensured, and the electric resistance of the whole thin film coil portion is reduced. can do. Further, in the modification shown in FIG. 18, the first and second coils, the third and fourth coils, .. Since the thin-film coil portions of the layers are formed, an interlayer insulating film (photoresist layer 16 in FIG. 18) for insulating and separating each layer is required, but in the modification shown in FIG. No inter-layer insulating film is required, and the coils are insulated and separated from each other only by a relatively thin insulating film 13 or the like. Therefore, even when many coils are laminated, the height of the thin film coil portion as a whole does not need to be so high, and as a result, the apex angle can be reduced.

In the example shown in FIG. 24, the first coil 12
A, the second coil 14a ', and the third coil 39 can be connected to each other, for example, as shown in FIG. 25 (a) shows the winding direction and connection mode of the first coil 12a and the second coil 14a ', and FIG. 25 (b) shows the winding direction mode of the third coil 39, respectively. It is a diagrammatically simplified representation. As shown in this figure, the contact pad P2 at the inner end of the first coil 12a and the contact pad P at the inner end of the third coil 39.
2'and a contact pad P3 'at the outer end of the third coil 39 and a contact pad P3 at the outer end of the second coil 14a'. First coil 1
The contact pad P1 formed on the outer end of 2a and the contact pad P4 formed on the inner end of the second coil 14a 'are connected to first and second external terminals, respectively, which are not shown. As shown in this figure, the first coil 12a and the second coil 14a 'are connected in series by a third coil 39 which also serves as a relay lead, and the winding directions thereof are all right-handed. Becomes Therefore, by applying a voltage between the above-mentioned first and second external terminals, it is possible to cause a current to flow through the first coil 12a, the third coil 39, and the second coil 14a 'in the same winding direction. it can. More specifically, P1-P2-P2'-P
The current flows in the order of 3'-P3-P4 or vice versa. Therefore, under the condition that the coil bundle widths LC are equal, the number of turns of the thin film coil can be further increased as compared with the case of the above-described embodiment. vice versa,
Under the condition that the number of turns of the thin-film coil is the same, the coil bundle width LC can be further shortened. In addition,
In the example shown in FIG. 25, the contact pad P2 at the inner end of the first coil 12a and the contact pad P3 at the outer end of the second coil 14a 'are connected by the third coil. In addition, the contact pad P1 at the outer end of the first coil 12a and the contact pad P4 at the inner end of the second coil 14a 'may be connected by the third coil 39. In this case, the contact pads P2, P3
Are respectively connected to the first and second external terminals.

The present invention has been described above with reference to some embodiments, but the present invention is not limited to these embodiments and various modifications are possible. For example, in FIG.
In the modification shown in FIG. 3, the first coil 12a and the second coil 14a are formed in the first layer, and the third coil 24a is formed.
The fourth coil 28 and the fourth coil 28 are formed on the second layer thereabove to have a two-layer structure, but more layer structures may be used. In this case, it is more efficient and preferable to form the total number of coils as an even number. Further, in the example shown in FIG. 18, the interlayer insulating film for insulating and separating the first layer and the second layer is the photoresist layer 16 which is an organic film. For example, an inorganic insulating layer such as a silicon oxide film may be used.

Further, in each of the above-described embodiments and its modifications, the surface of the base body composed of the substrate 1 and the insulating layer 2 is formed to be flat. However, in addition to this, a recess is previously formed in the substrate 1 or the insulating layer 2. After the formation, the respective layers from the lower shield layer 3 to the recording gap layer 9 may be laminated, and thin film coils such as the first coil 12a and the second coil 14a may be sequentially formed in this recessed region. In this case, the apex angle θ can be further reduced.

Further, in the above-described embodiment and its modification, the lower magnetic pole 7 is formed on the side of the base body composed of the substrate 1 and the insulating layer 2, and the upper magnetic pole piece 10 is provided via the recording gap layer 9.
Although a is formed, the magnetic layer having the same function as that of the upper magnetic pole in the above embodiment is formed on the side of the base body, and the magnetic gap layer 9 in the above embodiment is formed on the contrary. A magnetic layer having the same function as the lower magnetic pole may be formed. Specifically, in the trim structure shown in FIG. 14B, the lower magnetic pole 7 and the upper magnetic pole piece 10 are provided.
The structure of a may be reversed. For that purpose, for example, a groove corresponding to the magnetic pole width P2W is formed on the base side, and a lower magnetic pole piece having a shape and a function corresponding to the upper magnetic pole piece 10a of FIG. 14B is embedded in this groove. 14B, the upper magnetic pole having the shape and function corresponding to the lower magnetic pole 7 in FIG. 14B may be formed on the upper magnetic pole via the recording gap layer 9. That is, the magnetic pole width P2W is mainly defined by the lower magnetic pole, and the magnetic pole width P is set to a part of the upper magnetic pole and the recording gap layer.
It is formed so as to be 2 W.

Further, in the above-described embodiment and its modified example, as shown in FIG. 14, for example, the upper magnetic pole piece 10a and the upper magnetic pole 17 forming the upper magnetic layer form a boundary surface on a plane substantially parallel to the base surface. In addition, the upper magnetic pole piece 10a 'is connected as shown in FIG.
The upper magnetic pole 17 'may grip the upper magnetic pole piece 10a' by contacting not only the upper surface but also the end surface thereof with the upper magnetic pole 17 '. In the case of such a configuration, the contact area between the upper magnetic pole 17 'and the upper magnetic pole piece 10a' can be made larger, so that the saturation of the magnetic flux at this contact portion can be suppressed. Such an effect is
In particular, when the width of the upper magnetic pole piece 10a forming the pole tip (that is, the magnetic pole width P2W) is reduced to, for example, 1 μm or less, it becomes extremely remarkable, and the overwrite characteristic can be improved. Note that this FIG.
In FIG. 14, the same components as those shown in FIG. 14 are designated by the same reference numerals. The example shown in FIG. 26 is
This shows the case where the thin film coil portion has two layers.
In this example, the recording gap layer 9 is formed after the photoresist layer 16 is formed, so that the recording gap layer 9 is arranged between the first layer thin film coil and the second layer thin film coil. .

In the above-described embodiment and its modification, the upper magnetic pole facing the lower magnetic pole 7 with the recording gap layer 9 interposed therebetween is the upper magnetic pole 17 as shown in FIG.
The case where the upper magnetic pole piece 10a and the upper magnetic pole piece 10a are separately formed has been described, but the present invention is not limited to this, and the upper magnetic pole may be integrally formed. In this case, for example, as shown in FIG. 27, after forming the photoresist layer 25 so as to cover the thin film coil portion, the upper magnetic pole 17 and the integrated upper magnetic pole 37 which replaces the upper magnetic pole piece 10a are selectively formed. It may be formed. 27, the same components as those shown in FIG. 14 are designated by the same reference numerals. The example shown in FIG. 27 represents a case where the thin-film coil portion has two layers. Further, in this example, as the insulating layer below the thin film coil portion, the insulating layer 8 made of the inorganic material in FIG. 14 is used.
Instead of forming the photoresist layer 30, the recording gap layer 9 is formed before the formation of the photoresist layer 30.

Further, in the above-described embodiment and its modification, the method of manufacturing the composite type thin film magnetic head has been described. However, the present invention is a thin film magnetic head dedicated to recording having an induction type magnetic conversion element for writing, It can also be applied to a thin film magnetic head for both recording and reproduction. Further, the present invention can also be applied to a thin film magnetic head having a structure in which the order of stacking the write element and the read element is exchanged.

[0101]

As described above, the first to the fifteenth aspects of the present invention are provided.
According to the thin-film magnetic head of any one of claims 1 to 3 or the method of manufacturing the thin-film magnetic head of any one of claims 16 to 30, at least the bottom surface of the spiral groove which is the interwinding region of the first thin-film coil. And an insulating film and a conductive film are sequentially stacked so as to cover the side surface and the side surface, the insulating film sidewall is formed so as to cover only the conductive film on the side surface of the spiral groove, and is covered by the conductive film and the insulating film sidewall. Since the second thin-film coil is formed by embedding at least the inside of the opened spiral groove, the first thin-film coil and the second thin-film coil belong to the same layer through the insulating film, It is possible to reduce the winding body pitch per single layer in the thin film coil portion without particularly improving the processing accuracy in the forming process of the first thin film coil.
Further, since the conductive film on the side surface portion of the spiral groove is covered with the insulating film side wall, the function and action of the conductive film on the side surface portion of the spiral groove can be suppressed.

In particular, according to the thin film magnetic head of the fourth aspect or the method of manufacturing the thin film magnetic head of the nineteenth aspect, the insulating film sidewall functions as the seed layer of the conductive film on the side surface of the spiral groove. Since the second thin-film coil is formed by restraining and conducting plating growth using only the conductive film exposed on the bottom surface of the spiral groove as a seed layer, the plating from the conductive film on the side surface of the spiral groove is performed. It is possible to prevent the growth, and as a result, it is possible to suppress the formation of a cavity inside the second thin-film coil when the second thin-film coil is formed by plating growth.

According to the method of manufacturing a thin film magnetic head according to claim 6 or the method of manufacturing a thin film magnetic head according to claim 21, the insulating film is formed so as to reach the top of the first thin film coil, and the second The thin film coil of the first through the insulating film
Since the thin film coil is formed so as to cover a part of the top of the thin film coil, the cross-sectional area of the second thin film coil can be increased and the electrical resistance of the thin film coil can be reduced. Play.

Further, according to the thin film magnetic head of claim 7 or the method of manufacturing the thin film magnetic head of claim 22, the thin film coil portion is different from the first thin film coil and the second thin film coil. Between the inner peripheral end of the first thin film coil and the outer peripheral end of the second thin film coil, which are formed as a layer via an insulating layer, or between the outer peripheral end of the first thin film coil and the inner peripheral end of the second thin film coil. Since the third thin-film coil connecting between the thin-film coils is included, the first thin-film coil, the third thin-film coil, and the second thin-film coil are connected in series in this order and all the thin-film coils are connected. Since the winding directions of the thin film coil are the same, the total number of windings in the thin film coil portion can be further increased.

[Brief description of drawings]

FIG. 1 is a cross-sectional view for explaining one step in 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 illustrating a step following the step of FIG.

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

FIG. 13 is a cross-sectional view for explaining a step following FIG.

FIG. 14 is a cross-sectional view for explaining a step following the step of FIG.

FIG. 15 is a plan view of a thin film magnetic head manufactured by a manufacturing method according to an embodiment of the present invention.

16 is a plan view showing a simplified planar structure and connection relationship of a first coil and a second coil of the thin-film magnetic head shown in FIG.

FIG. 17 is a sectional view showing a structure of a thin film magnetic head according to a modification of the embodiment of the invention.

FIG. 18 is a cross-sectional view showing the structure of a thin film magnetic head according to another modification of the embodiment of the invention.

FIG. 19 is a plan view showing a simplified planar structure and connection relationship of first to fourth coils of the thin-film magnetic head shown in FIG.

20 is a graph for comparing and explaining the magnetic path length of the conventional thin film magnetic head shown in FIG. 34 and the magnetic path length of the thin film magnetic head shown in FIG. 18 according to an embodiment of the present invention. It is a top view of each thin film magnetic head.

FIG. 21 is a cross-sectional view showing a manufacturing process of a thin-film magnetic head according to still another modification of the embodiment of the present invention.

FIG. 22 is a cross-sectional view for explaining a step following FIG.

FIG. 23 is a cross-sectional view illustrating a step following the step of FIG.

FIG. 24 is a sectional view showing the structure of a thin film magnetic head according to still another modification of the embodiment of the invention.

25 is a plan view showing a simplified planar structure and connection relationship of the first coil to the third coil of the thin film magnetic head shown in FIG.

FIG. 26 is a sectional view showing a section of a thin-film magnetic head according to still another modification of the embodiment of the invention.

FIG. 27 is a cross-sectional view showing a cross section of a thin-film magnetic head according to still another modification of the embodiment of the present invention.

FIG. 28 is a cross-sectional view for explaining one step in the conventional method of manufacturing a thin film magnetic head.

29 is a cross-sectional view for explaining a step following FIG. 28. FIG.

FIG. 30 is a cross-sectional view for explaining a process following the process in FIG.

31 is a cross-sectional view for explaining a step following FIG. 30. FIG.

32 is a cross-sectional view for explaining a step following FIG. 31. FIG.

FIG. 33 is a cross-sectional view illustrating a step following the step of FIG. 32.

34 is a cross-sectional view for explaining a step following FIG. 33. FIG.

35 is a cross-sectional view showing a cross section parallel to the air bearing surface in the thin film magnetic head shown in FIG. 34.

[Explanation of symbols]

1 ... Substrate, 2 ... Insulating layer, 3 ... Lower shield layer, 4, 6 ...
Shield gap film, 5 ... MR film, 7 ... Lower magnetic pole, 8 ...
Insulating layer, 9 ... Recording gap layer, 10a, 10a '... Upper pole piece, 10b, 10b', 17a, 17c ... Upper pole piece, 11, 31 ... Seed layer, 12 ... Coil-like body, 12a
... first coil, 13 ... insulating film, 14, 14 '... plating layer, 14a, 14a' ... second coil, 15 ... photoresist pattern, 16, 25, 30 ... photoresist layer, 17, 17 ', 17b, 37 ... Upper magnetic pole, 18 ... Overcoat layer, 21 ... Relay lead, 22a, 38 ... Spiral groove, 22b ... Spiral ridge, 24, 39 ... Third coil, 28 ... Fourth coil, 32a ... Insulating film side wall, 33 ...
Photoresist layer, 35 ... Insulating layer, P1 to P5, P1 '
~ P4 '... Contact pads.

─────────────────────────────────────────────────── ─── Continuation of the front page (58) Fields investigated (Int.Cl. ⁷ , DB name) G11B 5/31 G11B 5/39

Claims (30)

(57) [Claims] 1. At least two magnetic layers including two magnetic poles that are magnetically coupled and a part of the side facing the recording medium faces each other via a gap layer, and the at least two magnetic layers or these magnetic layers. A thin-film magnetic head having a thin-film coil section disposed between other magnetic layers connected to each other, wherein the thin-film coil section has a first thin-film coil spirally formed, and An insulating film formed so as to cover at least the bottom surface and the side surface of the spiral groove that is the interwinding region of the thin film coil, and formed so as to cover at least the bottom surface and the side surface of the spiral groove covered by this insulating film A conductive film formed on the conductive film, an insulating film sidewall formed to cover only the conductive film on the side surface of the spiral groove of the conductive film, and the conductive film and the spiral groove covered by the insulating film sidewall. At least The second, which is formed so as to fill the inside
And a thin film coil. 2. The thin film magnetic head according to claim 1, wherein the conductive film functions as a base conductive film used when forming the second thin film coil. 3. The insulating film sidewall has a function of preventing the second thin film coil from being grown and formed by using the conductive film on the side surface of the spiral groove as a seed layer. The thin film magnetic head according to claim 2. 4. The second thin-film coil is formed by plating growth using the conductive film exposed at the bottom surface of the spiral groove as a seed layer. A thin film magnetic head as described in 1. 5. The thin-film magnetic head according to claim 1, wherein the insulating film is formed so as to reach the top of the first thin-film coil. 6. The thin film according to claim 5, wherein the second thin film coil is formed so as to cover a part of the top portion of the first thin film coil via the insulating film. Magnetic head. 7. The thin film coil portion is further formed as a layer separate from the first thin film coil and the second thin film coil via an interlayer insulating film, and the inner peripheral end of the first thin film coil is formed. And a third thin-film coil connecting between the outer peripheral end of the second thin-film coil and the outer peripheral end of the first thin-film coil and the inner peripheral end of the second thin-film coil. Item 7. A thin film magnetic head according to any one of items 1 to 6. 8. The first thin film coil is configured to include a thin underlying conductive film and a conductive plating layer selectively formed using the underlying conductive film as a seed layer. Item 8. A thin film magnetic head according to any one of items 1 to 7. 9. The thin-film magnetic head according to claim 1, wherein the insulating film is an inorganic insulating film. 10. The thin-film magnetic head according to claim 9, wherein the inorganic insulating film is made of aluminum oxide. 11. The thin film magnetic head according to claim 1, wherein the side wall of the insulating film is an inorganic insulating film. 12. The thin-film magnetic head according to claim 11, wherein the inorganic insulating film is made of aluminum oxide. 13. The insulating film retains a shape corresponding to the spiral groove even when it covers at least the bottom surface and the side surface of the spiral groove, which is the interwinding region of the first thin film coil. 13. The thin film magnetic head according to claim 1, wherein the thin film magnetic head is formed so as to have a film thickness that can be adjusted. 14. The thin film magnetic head according to claim 1, wherein a plurality of the thin film coil portions are hierarchically formed with an interlayer insulating film interposed therebetween. 15. The thin film magnetic head according to claim 1, further comprising a magnetoresistive element for reading. 16. At least two magnetic layers that are magnetically coupled and that include two magnetic poles, a part of the side facing the recording medium, facing each other via a gap layer, and the at least two magnetic layers or these magnetic layers. A method of manufacturing a thin film magnetic head having a thin film coil portion disposed between other magnetic layers connected to each other, wherein the step of forming the thin film coil portion forms a spiral first thin film coil. A step of forming an insulating film so as to cover at least a bottom surface and a side surface of the spiral groove that is the interwinding region of the first thin-film coil, and at least the spiral groove covered with the insulating film. Forming a conductive film so as to cover the bottom surface and side surfaces; forming an insulating film side wall so as to cover only the conductive film on the side surface portion of the spiral groove of the conductive film; film Method of manufacturing a thin film magnetic head which comprises a step of forming a second thin film coil so as to fill at least the interior of the spiral grooves covered by the wall. 17. The method of manufacturing a thin-film magnetic head according to claim 16, wherein the conductive film is used as a base conductive film when the second thin-film coil is formed. 18. The insulating film sidewall is used to prevent the second thin film coil from being grown by using the conductive film on the side surface of the spiral groove as a seed layer. A method of manufacturing a thin film magnetic head according to claim 17. 19. The step of forming the second thin film coil,
19. The method of manufacturing a thin film magnetic head according to claim 16, further comprising the step of performing plating growth using the conductive film exposed on the bottom surface of the spiral groove as a seed layer. 20. The method of manufacturing a thin film magnetic head according to claim 16, wherein the insulating film is formed so as to reach the top of the first thin film coil. 21. The thin film magnetic according to claim 20, wherein the second thin film coil is formed so as to cover a part of a top portion of the first thin film coil with the insulating film interposed therebetween. Head manufacturing method. 22. Further, between the inner peripheral edge of the first thin film coil and the outer peripheral edge of the second thin film coil, or between the outer peripheral edge of the first thin film coil and the inner peripheral edge of the second thin film coil. 17. The method according to claim 16, further comprising the step of forming a third thin-film coil for connecting with the first thin-film coil and a second thin-film coil as a different layer via an interlayer insulating film. 22. A method of manufacturing a thin film magnetic head as described in 21. 23. The step of forming the first thin-film coil includes a step of forming a thin underlying conductive film, and a step of selectively performing plating growth using the underlying conductive film as a seed layer. 23. A method of manufacturing a thin film magnetic head according to claim 16. 24. The method of manufacturing a thin film magnetic head according to claim 16, wherein the insulating film is an inorganic insulating film. 25. The method of manufacturing a thin-film magnetic head according to claim 24, wherein the inorganic insulating film is made of aluminum oxide. 26. The method of manufacturing a thin film magnetic head according to claim 16, wherein the side wall of the insulating film is an inorganic insulating film. 27. The method of manufacturing a thin-film magnetic head according to claim 26, wherein the inorganic insulating film is made of aluminum oxide. 28. The shape of the insulating film corresponding to the spiral groove remains even when the insulating film covers at least the bottom surface and the side surface of the spiral groove which is the interwinding region of the first thin film coil. 28. The method of manufacturing a thin-film magnetic head according to claim 16, wherein the thin-film magnetic head is formed to have a film thickness that allows it. 29. The plurality of thin film coil portions are hierarchically formed with an interlayer insulating film interposed therebetween.
29. A method of manufacturing a thin film magnetic head according to any one of 6 to 28. 30. The method of manufacturing a thin-film magnetic head according to claim 16, further comprising the step of forming a read magnetoresistive element.