JPH0765320A - Thin-film magnetic head and its production - Google Patents

Abstract

PURPOSE:To provide a thin-film magnetic head capable of obtaining good recording characteristics by minimizing the arrangement error of a pair of magnetic poles facing each other on a recording medium-opposed surfaces and having less varying characteristics by obtaining throat height with good accuracy. CONSTITUTION:This thin-film magnetic head has lower and upper main magnetic poles 30, 31 consisting of magnetic thin films which are magnetically coupled to each other and clamp coils 14 for driving therebetween and an auxiliary magnetic pole block 34 which is constituted by forming a magnetic gap 12 between first and second pole chips 35, 36 consisting of magnetic thin films. The auxiliary magnetic pole block 34 is interposed into the space part 33 formed between the ends of these lower and upper main magnetic poles 30 and 31 by magnetically coupling the respective lower and upper main magnetic poles 30, 31 and the respective first and second pole chips 35, 36. Since the auxiliary magnetic pole block 34 is constituted integrally in block, the parts near the magnetic gap 12 can be worked to an exact track width. Since a deviation is not generated in the first and second pole chips 35, 36, the good recording and reproducing characteristics are assured.

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 used for recording information on a recording medium and a manufacturing method thereof.

[0002]

2. Description of the Related Art An example of a conventional method of manufacturing a thin film magnetic head will be described with reference to FIGS. First, a seed layer (cathode for plating a permalloy magnetic pole) 2 of a FeNi film is formed on a substrate 1 made of a non-magnetic material as an underlayer by vapor deposition or sputtering (step S1). A photoresist layer 3 is formed on the seed layer 2 (step S2). next,
A photomask 4 having alignment marks (not shown) is arranged on the photoresist layer 3 (on the photomask 4, a magnetic pole forming pattern 5 and an alignment mark forming pattern 6 are arranged). The photoresist layer 3 is exposed through irradiation of ultraviolet rays 8 through the photomask 4 (step S3).

Subsequently, the photoresist (photoresist layer 3) is developed to dissolve the portion irradiated with the ultraviolet rays 8 (step S4). Next, when the seed layer 2 is used as a cathode and the permalloy (FeNi) film 9 is electrodeposited, the permalloy (permalloy film 9) grows only in the exposed portion of the seed layer 2 (step S
Five). After this, photoresist (photoresist layer 3)
Are removed (step S6) and the unnecessary seed layer 2 is removed (step S7), the lower magnetic pole 10 and the alignment pattern 11 are removed.
Is completed.

Next, the non-magnetic film 13 for forming the magnetic gap 12,
The driving coil 14 and the photoresist 16 which also serves as the coil insulator 15 are formed (step S8). Step S8
Then, raise the temperature to the softening point of the photoresist 16,
The photoresist 16 is flattened by eliminating the steps (step S9). Next, the seed layer 18 for the top pole 17 and the photoresist 19 are formed (step S10).

Then, a photomask 20 for exposing the upper magnetic pole 17 is formed.
The alignment (positioning) is performed (through the alignment mark 21 of the photomask 20 for exposing the upper magnetic pole 17 and looking for the alignment pattern 11 that has already been created, looking for a matching position) (step S11). Next, the photomask 20 for exposing the upper magnetic pole 17 is fixed and the photoresist 19 is exposed (irradiated with ultraviolet rays 8) (step S12).

Next, the photoresist 19 is developed (step S13). Subsequently, a seed layer 18 for the upper magnetic pole 17 is used as a cathode to form a permalloy film 22 to be the upper magnetic pole 17 by electrodeposition (the permalloy film 22 is not attached to the portion covered with the photoresist 19) (step S14). ). The photoresist 19 and the seed layer 18 for the top pole 17 are removed (step
S15) Complete a thin film magnetic head.

11 to 13 show an example of a thin film magnetic head obtained by the above-described manufacturing method. In the figure, lower and upper magnetic poles 10 and 17 are substantially rectangular lower side and upper side base end portions 10, respectively.
a, 17a, lower side, upper side connecting parts 10b, 17b and substantially rectangular lower side, upper side gap forming parts 10c, 17c. A convex portion 23 projecting downward is formed in the central portion of the upper base end portion 17a, and the convex portion 23 forms the lower base end portion 10a.
The lower and upper magnetic poles 10 and 17 are magnetically coupled by abutting on a. The upper side connecting portion 17b is formed with a recessed portion facing downward, and the drive coil 14 is sandwiched between the lower and upper magnetic poles 10, 17 at the position of this recessed portion. A magnetic gap 12 is formed in the lower side and upper side gap forming portions 10c and 17c. The recording medium (not shown) faces the lower and upper gap forming portions 10c and 17c. Bottom side,
The surface of the upper side gap forming portions 10c and 17c facing the recording medium is hereinafter referred to as the recording medium facing surface 25.

The lower-side and upper-side connecting portions 10b and 17b sandwiching the drive coil 14 are wide, and the width becomes narrower (narrowed down) as it becomes the recording medium facing surface 25.
The magnetic head efficiency is improved. Recording medium facing surfaces of lower side and upper side gap forming portions 10c and 17c
The width dimension at 25 is set equal to the track width W _T. The lower and upper magnetic poles 10 and 17 are formed by an optical exposure technique, and the two are superposed by the aligning exposure.

[0009]

By the way, in order to ensure good characteristics and the like, the widths of the lower side and upper side gap forming portions are set to be as equal as possible, and the weight gap is set with the magnetic gap interposed therebetween. It is desired that the match be perfectly matched. However, in the above-described thin film magnetic head, since the lower and upper magnetic poles 10 and 17 are formed by the optical exposure technique and both are superposed by the aligning exposure, the lower side and upper side gap forming portions 10c and 17c are formed. It is difficult to make the widths equal to the gap width W _T, and even if the widths of the lower side and upper side gap forming portions 10c and 17c can be set to be equal to each other, they will be misaligned due to misalignment. It is difficult to achieve proper polymerization,
I was not able to meet the demand.

To solve this problem, as shown in FIG. 13, the upper side gap forming portion 17c is processed so that its width is equal to the track width W _T as much as possible, while the lower side gap forming portion 10c is overlapped. The width is made wider than the track width W _T within a range capable of covering the alignment error, and the lower side and upper side gap forming portions 10c and 17c are configured so as not to come off from each other.

However, in this case, the lower and upper magnetic poles 10, 17
The widths of the magnetic fields are different from each other and the imbalance of the superposition causes the write magnetic field from the magnetic head to be non-uniform. Also, one of the lower and upper magnetic poles 10, 17 has a track width W _T
On the other hand, when the other one has a width wider than the track width, the adjacent track is interfered when reading from the recording medium, and the recording / reproducing characteristics and the off-track characteristics are deteriorated. This problem becomes more remarkable as the track width W _T is narrower.

The above-mentioned lower and upper magnetic poles 10 and 17 are not overlapped with each other, and the lower and upper gap forming portions are formed.
In order to match the widths of 10c and 17c with the track width W _T , the widths near the lower and upper gap forming portions 10c and 17c are set sufficiently large in advance, and then the track width W _T
Lower side and upper side gap forming parts 10c, 1
A processing method is adopted in which the vicinity of 7c is simultaneously etched. In this method, the lower and upper gap forming portions 10c
, 17c can be eliminated. However,
Since an etching process is newly introduced, the manufacturing process becomes complicated accordingly. In addition, since the lower and upper magnetic poles 10 and 17 are thick, it takes etching time, which makes it difficult to make the track width W _T highly accurate.

Further, in the thin film magnetic head shown in FIGS. 11 to 13, the lower and upper magnetic poles 10 and 17 are in contact with each other at the lower side and the upper side base end portions 10a and 17a, and the lower side and upper side connecting portions 10b. , 17b, the gap is widened because the coil 17 is sandwiched, and in the gap portion 12, the gap is narrowed down to the gap size again. It is necessary to change this gap as smoothly as possible. If the gap changes discontinuously, a magnetic pole may be generated in the discontinuous portion, which may reduce the efficiency of the magnetic head. Coil insulator to avoid this problem
15 uses organic materials. Then, the heat treatment smoothes the surface and the end of the organic material 15 to make the gap change toward the magnetic gap 12 smooth. However, the fluidity varies depending on the formation of the organic material and the heating conditions, and the throat height H _T (upper magnetic pole 17 and lower magnetic pole 17
It was difficult to keep the contact height in the magnetic gap of 10) constant, which increased the variation in the characteristics and also caused the yield to decrease.

The present invention has been made in view of the above circumstances, and it is possible to obtain an excellent recording characteristic by minimizing an error in the arrangement of a pair of magnetic poles facing each other on the recording medium facing surface.
Moreover, it is an object of the present invention to provide a thin film magnetic head capable of accurately producing a throat height and having characteristics with little variation, and a manufacturing method thereof.

[0015]

In order to achieve the above object, a thin film magnetic head according to the present invention comprises a magnetic thin film, one end of which is magnetically coupled to each other and a driving coil is sandwiched therebetween. A second main magnetic pole and a first magnetic thin film,
An auxiliary magnetic pole block formed by forming a magnetic gap between the second pole tips, and the auxiliary magnetic pole block in a space formed between the other ends of the first and second main magnetic poles, Each of the first and second main magnetic poles and each of the first and second pole tips are magnetically coupled and interposed.

In the thin film magnetic head manufacturing method of the present invention, in order to achieve the above object, after forming a first main pole on a substrate and a drive coil positioned on the center side of the first main pole, A magnetic thin film, a non-magnetic film, and a magnetic thin film are laminated on the upper surface side, and an unnecessary portion is removed by performing an etching process or a lift-off process from the magnetic thin film, the non-magnetic film, and the magnetic thin film to a first pole tip, a magnetic gap, and a second magnetic film. And the auxiliary pole block is formed on one end side of the first main pole.

[0017]

According to the structure of the device of the present invention, the auxiliary magnetic pole block interposed between the end portions of the first and second main magnetic poles has the first and second auxiliary magnetic pole blocks.
Since the pole chip and the magnetic gap are integrally formed into a block, the portion near the magnetic gap, which plays an important role in writing and reading, can be accurately processed to have the track width. Furthermore, there is no gap between the first and second pole chips that sandwich the magnetic gap,
Good recording and reproducing characteristics can be secured.

Further, it is possible to set the saturation magnetic flux density and the magnetic permeability of the soft magnetic thin film which becomes the first and second pole tips of the auxiliary magnetic pole block to be larger than that of the soft magnetic thin film of the main magnetic pole. By setting in this way, it is possible to make the change in magnetic field strength near the magnetic gap steep, reduce the disturbance of the magnetic field due to the difference in width between the main pole and the first and second pole tips, and improve the characteristics. it can.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT A first embodiment of the present invention will be described below with reference to FIGS.
It will be described based on. In the figure, 30 and 31 are lower and upper main magnetic poles (first and second main magnetic poles) made of a soft magnetic thin film.
The lower main magnetic pole 30 is formed on the substrate 1.

The lower and upper main magnetic poles 30 and 31 are formed at one end thereof with substantially rectangular lower and upper base end portions 30a and 31a, respectively. The lower and upper main magnetic poles 30 and 31 are connected to the lower and upper base end portions 30a and 31a, respectively, and the lower and upper connection portions 30b and 31b having the gradually decreasing width dimension are formed. This lower side,
A substantially rectangular lower side and upper side gap forming portions 30c, 31c are provided so as to be connected to the upper side connecting portions 30b, 31b. A soft magnetic thin film 32 is provided between the upper base end 31a and the lower base end 30a, and the lower and upper main magnetic poles 30, 31 are magnetically coupled. The lower and upper main magnetic poles 30 and 31 sandwich a drive coil 14 located in the central portion thereof and formed in a spiral shape by a thin film conductor.

An auxiliary magnetic pole block 34 is provided in a space 33 formed between the other end of the upper main magnetic pole 31 and the other end of the lower main magnetic pole 30. The auxiliary magnetic pole block 34 is composed of magnetic thin films 35A and 36A, and has first and second pole tips 35 and 36.
And a non-magnetic thin film 12A that is inserted into the gap formed between the first and second pole tips 35 and 36 to form the magnetic gap 12, and the first and second pole tips 35,
36 is magnetically coupled to the lower and upper main magnetic poles 30 and 31, respectively. In this case, the auxiliary magnetic pole block 34
Is a magnetic thin film 35A forming the first pole tip 35, a non-magnetic thin film 12A forming the magnetic gap 12, and a magnetic thin film 36A forming the second pole tip 36 are sequentially laminated by a technique such as sputtering. It has been made into a block.

By forming the auxiliary magnetic pole block 34 by integrally forming a block as described above, the track width W can be accurately set in the vicinity of the magnetic gap 12 (the portion corresponding to the auxiliary magnetic pole block 34) which plays an important role in writing and reading. Can be processed to be _T. Further, by forming the auxiliary magnetic pole block 34 as an integrated block, the first and second pole tips 35 and 36 that sandwich the magnetic gap 12 are not displaced. Therefore, good recording and reproducing characteristics can be secured. Further, along with this, it is not necessary to separately form the upper and lower magnetic poles and superpose them in the aligning exposure, which has been performed in the conventional thin film magnetic head.

The closed magnetic circuit of the entire magnetic head has an auxiliary magnetic pole block 34 integrally formed as a block, a lower magnetic pole block 34, an upper magnetic pole 30,
The upper and lower main magnetic poles 30 and 31 are sandwiched by 31 and are joined by a soft magnetic thin film 32 provided in the rear gap portion. In the magnetic head having such a structure, as shown in FIG. 3, the lower and upper main magnetic poles 30 and 31 are exposed on the same surface as the auxiliary magnetic pole block 34 on the recording medium facing surface.
Magnetic gap 12 that plays an important role in writing and reading
It is located farther away. Therefore, even if the width dimensions of the lower and upper main magnetic poles 30 and 31 are slightly different from each other or the positions thereof are deviated from each other, the recording / reproducing characteristics are hardly affected.

Further, since the recording / reproducing characteristics are hardly affected even if the positions are deviated from each other, the lower and upper main magnetic poles 3 including the auxiliary magnetic pole block 34 are included.
It is only necessary to select the width of 0, 31 and the alignment accuracy of the lower and upper main magnetic poles 30, 31. For this reason, the conventional aligning exposure technique can be sufficiently used.

As described above, the feature of the thin film magnetic head in the present invention is that the auxiliary magnetic pole block 34 is formed as an integrated block. As a result, the track width W can be accurately set in the vicinity of the magnetic gap 12 (the portion corresponding to the auxiliary magnetic pole block 34) which plays an important role in writing and reading.
Can be processed to be _T. Since the widths of the first and second pole chips 35 and 36 can be set to be equal and the placement error can be minimized, good recording characteristics can be obtained.

Next, a manufacturing method of the present invention will be described with reference to FIGS. 4 and 5. In FIG. 4, a recess 40 having the same shape as the lower main magnetic pole 30 is formed on the surface of the substrate 1 by a technique such as ion etching. In this recess 40, the lower main pole 30
Is embedded. The pattern width W _P of the tip portion of the main magnetic pole (the portion facing the recording medium) is set to be slightly wider than the track width W _T within a range that can cover the positional accuracy of the formation of the auxiliary magnetic pole block 34 (FIG. 4 (a1), (A2)).

After forming the lower main magnetic pole 30, a driving coil is formed.
Forming 14 After forming the driving coil 14, the whole is covered with a photoresist 41. By exposing and developing the photoresist 41, holes 42 and 43 reaching the lower main magnetic pole 30 are formed in the portion of the photoresist 41 where the auxiliary magnetic pole block 34 is formed and the rear gap portion (FIG. 4 (b1),
(B2)).

The width of the hole 42 at the portion where the auxiliary magnetic pole block 34 is formed is accurately adjusted to the track width W _T. The holes 42 and 43 are shorter than the width of the tip portion of the lower main magnetic pole 30. Further, the right end of the hole 42 is indicated by a chain line B (see FIG.
(E1)), and throat height H _T at the final stage
Is set to a position where a predetermined throat height H _T can be obtained.

After forming the resist pattern (photoresist 41), the soft magnetic thin film 35B which becomes the first pole tip 35,
The non-magnetic film 12A forming the magnetic gap 12 and the soft magnetic thin film 36B forming the second pole tip 36 are sequentially laminated (FIG. 4C). After the stacking, if the photoresist 41 is removed, the stacks stacked on the photoresist 41 are separated (so-called lift-off technique), and the first and second pole chips are formed.
Auxiliary magnetic pole block 34 including 35 and 36 and the magnetic gap 12
Are formed (FIG. 4D).

As is apparent from this manufacturing method, the magnetic gap 12 and the first and second pole chips 35 and 36 that sandwich the magnetic gap 12 are formed with the same resist pattern.
Therefore, there is no positional deviation. Further, the track width W _T is determined by the accuracy of the resist pattern, and the accuracy can be greatly improved as compared with the conventional method.

After forming the auxiliary magnetic pole block 34, a flattening process is performed and the upper main magnetic pole 31 is formed thereon (FIG. 4).
(E1), (e2)). The alignment position has only to be within the tip width of the upper magnetic pole 17 of the auxiliary magnetic pole block 34, and can be easily achieved by the conventional alignment exposure technique. On the contrary, the tip width of the upper main magnetic pole 31 may be set to be wide enough to allow the overlapping by the aligning exposure technique.

After forming each layer, in order to obtain the shape of the final thin film magnetic head, polishing is performed up to the alternate long and short dash line B in FIGS. 4 (e1) and (e2). Point B is polished around the polishing amount detection mark, but the polishing amount detection mark, that is, point B and point A that defines the throat height, can be formed by using the same mask used when forming the auxiliary magnetic pole block as the polishing amount detection mark. The mutual positions can be defined accurately. Therefore, the throat height H _T can be accurately obtained.

The soft magnetic thin films 35B and 36B of the first and second pole tips 35 and 36 and the soft magnetic thin films of the lower and upper main magnetic poles 30 and 31 may have the same magnetic characteristics. However, in the present invention, a soft magnetic thin film having different magnetic properties can be used. In particular, the soft magnetic thin film 35 that becomes the first and second pole tips 35 and 36 of the auxiliary magnetic pole block 34.
The saturation magnetic flux density and permeability of B and 36B are the lower and upper main magnetic poles.
By making the soft magnetic thin film of 0, 31 larger than that of the soft magnetic thin film, the change in the magnetic field strength in the vicinity of the magnetic gap 12 is sharpened, and the lower and upper main magnetic poles 30, 31 and the first and second pole tips are formed.
The disturbance of the magnetic field due to the difference in width between 35 and 36 can be reduced, and the characteristics can be improved.

In the conventional thin film magnetic head, as shown in, for example, FIGS. 11 to 13, the magnetic poles (lower and upper magnetic poles 10 and 17) of the recording medium facing surface 25 are integrally formed with the magnetic gap 12 interposed therebetween. There is. On the other hand, in the present invention, the one corresponding to the lower magnetic pole 10 on the conventional recording medium facing surface 25 side is composed of the lower main magnetic pole 30 and the first pole tip 35, and the upper magnetic pole 17 on the conventional recording medium facing surface 25 side. Is composed of the upper main magnetic pole 31 and the second pole tip 36, and is exposed to the recording medium facing surface 25. When a magnetic discontinuity occurs between two kinds of soft magnetic thin films, this boundary becomes a pseudo gap and noise is generated. In order to prevent the generation of noise, it is necessary to prevent the generation of the non-magnetic layer as much as possible at the time of manufacturing to improve the magnetic contact. At the same time, the effect of the pseudo gap can be removed by slightly lowering this portion from the slider surface by, for example, ion etching. In the above embodiment, the case where the auxiliary magnetic pole block 34 is formed after the formation of the drive coil 14 has been described as an example. However, after formation of the first and second pole tips 35 and 36, the drive coil 14 is formed.
It is also possible to create.

In the embodiment described above, the auxiliary magnetic pole block 34
I used lift-off technology to create it, but instead of this,
First, as shown in FIG. 6, first and second pole tips 35,
The soft magnetic thin films 35B and 36B and the nonmagnetic thin film 12A for the gap forming the 36 are formed on the entire surface (FIG. 6A), and only the first and second pole tips 35 and 36 are covered with the photoresist 50. (FIG. 6B), the other portion is removed by etching (FIG. 6C) to form the auxiliary magnetic pole block 34 (FIG. 6C).
(D)) can also be performed.

Further, in the conventional thin film magnetic head, an organic material is used for the insulating film of the drive coil 14 in order to set the narrowing of the lower side and upper side connecting portions 10b and 17b as smooth as possible. However, the fluidity varies depending on the formation of organic material and heating conditions, and it is difficult to always keep the point A (see FIG. 11) that determines the throat height H _T constant.
As a result, variations in characteristics are increased, which causes a reduction in yield. On the other hand, according to the present invention, since the points A that define the polishing amount detection mark can accurately define their mutual positions as described above, the throat height H _T can be accurately obtained.

[0037]

Since the device of the present invention is the thin film magnetic head configured as described above, the auxiliary magnetic pole block interposed between the end portions of the first and second main magnetic poles is provided in the first and second auxiliary magnetic pole blocks. Since the two pole chips and the magnetic gap are integrally formed into a block, the portion near the magnetic gap, which plays an important role in writing and reading, can be processed to have an accurate track width. Furthermore, since there is no deviation between the first and second pole chips that sandwich the magnetic gap, good recording / reproducing characteristics can be secured.

Further, it becomes possible to set the saturation magnetic flux density and the magnetic permeability of the soft magnetic thin film which becomes the first and second pole tips of the auxiliary magnetic pole block larger than that of the soft magnetic thin film of the main magnetic pole. By setting in this way, it is possible to make the change in magnetic field strength near the magnetic gap steep, reduce the disturbance of the magnetic field due to the difference in width between the main pole and the first and second pole tips, and improve the characteristics. it can.

[Brief description of drawings]

FIG. 1 is a sectional view showing a thin film magnetic head of a first embodiment of the invention.

FIG. 2 is a plan view showing the thin film magnetic head.

FIG. 3 is a front view showing the thin film magnetic head.

FIG. 4 is a process drawing showing the method of manufacturing the thin-film magnetic head of the second embodiment of the present invention.

FIG. 5 is a perspective view showing a magnetic gap portion of a thin film magnetic head obtained by the same manufacturing method.

FIG. 6 is a process drawing showing a method of manufacturing a thin film magnetic head of another embodiment of the present invention.

FIG. 7 is a diagram showing the steps from seed layer formation to electrodeposition processing in a conventional thin-film magnetic head manufacturing method.

8 is a diagram showing a process of steps S5 to S10 following FIG. 7. FIG.

9 is a diagram showing a process of steps S11 to S12 following FIG. 8. FIG.

FIG. 10 is a diagram illustrating steps S13 to S15 subsequent to FIG. 9;
It is a figure which shows the process of.

FIG. 11 is a sectional view showing an example of a conventional thin film magnetic head.

FIG. 12 is a plan view showing the thin film magnetic head.

FIG. 13 is a perspective view showing a magnetic gap portion of the thin film magnetic head.

[Explanation of symbols]

 12 Magnetic gap 14 Drive coil 30 Lower main pole 31 Upper main pole 33 Space 34 Auxiliary pole block

Claims (3)

[Claims] 1. First and second magnetic thin films having one ends magnetically coupled to each other and sandwiching a driving coil therebetween.
Main magnetic pole and an auxiliary magnetic pole block formed by forming a magnetic gap between the first and second pole tips made of a magnetic thin film, and between the other end portions of the first and second main magnetic poles. A thin film in which the auxiliary magnetic pole block is interposed in the formed space by magnetically coupling each of the first and second main magnetic poles and each of the first and second pole tips. Magnetic head. 2. The thin film magnetic head according to claim 1, wherein the magnetic properties of the magnetic thin films forming the first and second pole tips and the magnetic properties of the magnetic thin films forming the first and second main poles are different. The thin film magnetic head that was made. 3. The thin film magnetic head according to claim 1, wherein a magnetic thin film to be a first pole chip, a non-magnetic thin film to be a magnetic gap, and a magnetic thin film to be a second pole chip are sequentially laminated and then collectively formed. A method of manufacturing a thin film magnetic head, characterized in that an auxiliary magnetic pole block is formed by lift-off or etching.