JP2003022638A - Thin-film magnetic head and method of manufacturing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To form a thin-film magnetic head to be installed to a recording and/or reproducing device, such as a hard disk drive(HDD), so that the impact resistance when the magnetic head comes into contact with a hard disk, etc., is improved. SOLUTION: The thin-film magnetic head 30 formed with a slider surface 31a which is formed in a rounded shape at respective angle parts and to a shape having no sharp angles on the both ends of respective sides is obtained by subjecting the slider surface 31a of a substrate 31 worked in height into a black shape to patterning of a resist 34 in compliance with the shape of the slider, forming the angle parts of the resist surface to have rounded shapes by the shrinkage arising from the thermal curing of the resist 34 and subjecting the resist to dry etching in this state to transfer the shape of the resist surface to the slider surface 31a and peeling the resist 34.

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 constituting a flying head provided in, for example, a hard disk drive (HDD) and a manufacturing method thereof.

[0002]

2. Description of the Related Art A hard disk drive (HDD) is equipped with a floating head that floats the head above a disk surface of a hard disk (HD) which is a recording medium with a minute space therebetween. As the die head, a thin film magnetic head is used in which the head element, a magnetic material to be a core and a coil are formed by the same method as a semiconductor manufacturing process in order to miniaturize the head and achieve high density.
As shown in FIG. 12, the thin film magnetic head 101 is supported by a suspension 102 so as to be swingable in a contacting / separating direction with respect to a hard disk HD.

Since a hard disk drive (HDD) is a complicated and precise device, it is very sensitive to external shocks and vibrations, and in particular, when the hard disk drive (HDD) falls or gives vibration. A general internal shock phenomenon that occurs when a magnetic field is bounced off the surface of the disk is called a head strap.

That is, as shown in FIG. 13, the magnetic head 101 and the suspension 102 supporting the magnetic head 101 are stable on a hard disk (HD) (FIG. 13A).
When a shock is applied, the head 101 jumps from the hard disk (HD) due to this shock (FIG. 13B). When this magnetic head jumps, it collides with the disk surface of the hard disk (HD) due to the reaction of the suspension 102 (see FIG. 13).
C) By repeating this operation, the magnetic head 1 hits the disk surface of the hard disk (HD) (FIG. 13D), scratches the disk surface, and dust is generated.

As a result, the recorded data recorded on the hard disk (HD) may be damaged, and the corners of the magnetic head 101 may be chipped off and the magnetic head 101 may be damaged. This is when the hard disk (HD) is spinning
The magnetic head 101 tends to be scratched because the corner portion on the side (leading side) facing the rotation of the disk is stuck in the disk surface.

Further, the magnetic head 101 is considered to be less likely to be scratched because the corner portion on the escape side (trading side) with respect to the rotation of the disk is in a state of escape from the disk surface, but the head element is There is an alumina (Al ₂ O ₃ ) film as a base layer on the formed surface, and since alumina is brittle, the corner portion tends to be chipped, which is one of the causes of damage to the magnetic head 101.

Therefore, it is necessary to improve the impact resistance of the magnetic head. Therefore, in the conventional magnetic head, as a structure for improving the impact resistance, the entire outer peripheral edge of the magnetic head or the magnetic recording medium is used. Air bearing surface (Air Bear) which is a slider surface facing each other.
ring surface; hereinafter referred to as ABS surface), a structure in which the entire outer peripheral edge of the pattern is largely chamfered, that is,
Processing generally called blend processing was the mainstream.

[0008]

However, in order to obtain this magnetic head structure, as shown in FIG. 14, in the final step of the head processing step, the magnetic heads 101 are clamped one by one on the jig 103, and As shown in FIG. 15, it is necessary to process using the rotating body 105 to which the polishing sheet 104 is attached, and there is a drawback that the productivity is very poor.
In addition, the magnetic head 101 is handled when it is clamped by the jig 103, but this handling also causes defects such as chipping scratches and reduces yield.

Further, since the entire outer peripheral surface of the magnetic head 101 is chamfered, the ABS surface design for controlling the flying of the magnetic head 101 is also restricted. At the same time, there is a high risk of coming into contact with the ABS surface during processing, and if it comes into contact with it, for example, a diamond-rec carbon (DLC) film coated as a protective film will peel off, and the reliability of the magnetic head will be impaired. .

Further, there are drawbacks such that it is difficult to control the dimensions in terms of processing conditions, the processing time is long, and the structure of the magnetic head processing apparatus is complicated.

The present invention has been made in view of the above points, and has a floating head having advantages such as improved impact resistance, simplified processing steps, improved production efficiency, and high reliability. An object of the present invention is to provide a thin film magnetic head as described above.

[0012]

In order to achieve the above object, the present invention is a levitation type which is supported by a suspension and floats and opposes a recording surface of a magnetic recording medium which is rotated and keeps a predetermined distance. A thin film magnetic head constituting a head, in which each corner of a slider surface facing a recording surface of a magnetic recording medium is formed in an arc surface shape.

Further, in the above structure, the thin film magnetic head may have a structure in which the entire peripheral edge of the slider surface is angled.

In the thin film magnetic head constructed as described above, resist is patterned on the slider surface, and the corners of the resist surface are formed into arcs by shrinkage of the resist due to thermosetting, and the resist is used as a mask. As a result, the shape of the resist surface is transferred by dry etching, and the corners of the slider surface or the entire peripheral edge of the slider surface are rounded. In this structure, dry etching can be performed by reactive ion etching.

The thin-film magnetic head according to the present invention constructed as described above has a structure in which each corner portion of the slider surface facing the recording surface of the magnetic recording medium is formed into an arc surface shape, so that it can be protected from an external impact. The impact resistance when the thin-film magnetic head comes into contact with the magnetic recording medium is improved, and the occurrence of scratches on the magnetic recording medium, damage to recorded data and damage to the thin-film magnetic head itself are prevented.

In particular, by taking an angle at the corner of the head slider surface facing the direction of rotation of the magnetic recording medium, the impact on the magnetic recording medium is mitigated to prevent damage to the magnetic recording medium, and the head slider is also prevented. By arranging the corners of the corners on the side away from the rotation of the magnetic recording medium, chipping of the corners is prevented and damage to the magnetic head element is prevented.

Then, the resist is patterned on the surface of the head slider, the corners of the resist surface are formed into an arcuate shape by shrinkage of the resist by thermosetting, and dry etching such as reactive ion etching is performed using this resist as a mask. Since the shape of the resist surface is transferred and the corners of the slider surface or the entire peripheral edge of the slider surface are angled, all corners or the entire peripheral edge of the slider surface must be angled at the same time. It can be formed easily and easily, and it can be processed in a series of bar states, greatly improving production efficiency.

[0018]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to FIG.
~ It demonstrates with reference to FIG.

This embodiment constitutes a thin film magnetic head applied to a thin film head slider for a hard disk drive (HDD).

First, FIG. 1 shows a schematic block diagram of a thin film magnetic head to which the present invention is applied. A slider surface facing a magnetic recording medium, that is, a so-called air bearing surface (A) is shown.
It is shown as a cross-sectional view taken along a plane perpendicular to the irbearing surface (hereinafter referred to as ABS surface). The thin-film magnetic head 10 is a composite thin-film magnetic head formed by integrally laminating a read-only magnetoresistive head (MR head) 1 and a write-only inductive head 2.

The MR head 1 comprises a magnetoresistive effect element (GM
An R element or an MR element; hereinafter referred to as an MR element) 14 is arranged on the ABS surface side facing the magnetic recording medium, and one end surface is exposed to the magnetic recording medium. Specifically, for example, AlTiC (Al ₂ O ₃ Ti
C) etc. on the substrate 11 made of alumina (Al ₂ O ₃ )
The lower shield 12 is formed of a soft magnetic film such as the above to form the lower magnetic pole. An MR having a magnetoresistive effect on the lower shield 12 via a lower gap film 13.
The element 14 is arranged. Behind the MR element 14, an insulating film 15 made of, for example, Al ₂ O ₃ is buried to fill the step of the MR element 14.

An upper gap film 16 is formed on the MR element 14.
An intermediate shield 17 made of a soft magnetic film is provided via the. The intermediate shield 17 constitutes an upper magnetic pole, and the lower gap film 13 and the upper gap film 16 form a gap of the MR head 1.

On the other hand, the inductive head 2 is made of a soft magnetic film and constitutes the MR head 1.
7 as the lower magnetic core, on this intermediate shield 17,
For example, it has a recording gap film 18 made of SiO ₂ or Al ₂ O ₃ . On the tip side of the recording gap film 18 facing the magnetic recording medium, the upper pole 1 made of a magnetic film is formed.
9 is formed. Behind this upper pole 19,
The insulating layer 20 is embedded and the surface is planarized. A coil 21 made of a conductor is formed on the flattened surface, and an insulating film 22 is formed so as to cover the coil 21. Although not shown, the coil 21 is formed in a spiral shape in plan view. Then, using the coil 21, a signal is supplied to the inductive head 2 by an electromagnetic conversion action.

Further, an upper core (back yoke) 23 made of a magnetic film is formed above the insulating film 22 and connected to the upper pole 19. The upper pole 19 and the upper core (back yoke) 23 constitute an upper magnetic core. The upper core (back yoke) 23 is connected to the intermediate shield 17 in the rear to form a magnetic path.

The thin film magnetic head 10 thus constructed
Since it is formed by the vacuum thin film forming technique, it is easy to make a fine dimension such as a narrow track and a narrow gap, high resolution recording / reproducing is possible, and it is a magnetic head compatible with high density magnetic recording.

Further, in the thin film magnetic head 10 thus constructed, the coil 10 can be formed in two layers. In this case, an insulating film is formed to cover the first coil and the surface is flattened, and the second coil is formed on the flattened surface in a planar shape in the same spiral shape as the first coil. . Then, an insulating film is formed to cover the second coil, and an upper core (back yoke) made of a soft magnetic material is formed on the flattened surface of the insulating film.
A thin film magnetic head having a coil formed in two or more layers is constituted.

As described above, in the case of a thin film magnetic head having two or more layers of coils, the number of turns of the coil can be increased while the magnetic path length remains short, as compared with a thin film magnetic head of one layer of coil, It is possible to improve the overwrite characteristic of the magnetic head, that is, the recording ability.

Next, an embodiment of the present invention will be described with reference to FIGS.
The thin-film magnetic head of this embodiment is used as a floating head provided in a hard disk drive (HDD), and has improved shock resistance when the head comes into contact with the hard disk due to external shock. It was made to let.

FIG. 2 shows an example of the thin-film magnetic head according to the embodiment of the present invention. The phenomenon that the head contacts the hard disk may be caused especially by contacting from the leading edge of the head, which is the side facing the rotation of the hard disk. It is known, and as a method to improve this, a head structure that forms a minute arcuate surface shape (R surface shape) at the first corner and the second corner to reduce the impact is provided, and in order to enhance safety, the facing surface side The third and fourth corners (on the trading side) are also formed in the same R shape, and all the corners of the ABS surface, which is the slider surface, are R-shaped head structures.

That is, the thin film magnetic head 30 of the example shown in FIG. 2 also has a magnetoresistive effect element (MR element) 1 exclusively for reproduction and an inductive head 2 exclusively for recording as in the thin film magnetic head 10 shown in FIG. 31 is a composite-type thin film magnetic head formed by stacking layers 31 by a vacuum thin film forming technique.

The substrate 31 of the thin film magnetic head 30 has a required surface area, and this surface serves as a negative pressure slider surface 31a as an air bearing surface (ABS surface) for the hard disk, and floats on the slider surface 31a. An ABS pattern surface 32 having a required shape for forming the head element portion 33 including the MR element 1 and the inductive head 2 is formed on the one end surface 31b side of the substrate 31.

The corner portion of the substrate 31, which is the negative pressure slider portion of the thin film magnetic head 30, that is,
One end surface 31 on which the head element portion 33 of the substrate 31, which is the trading side which is the side that escapes with respect to the rotation of the hard disk, is formed together with the first corner portion 31c _{1 and} the second corner portion 31c ₂ on the leading side 31c of the slider surface 31a.
The third corner portion 31b ₁ and the fourth corner portion 31b ₂ that are both corner portions on the b side are formed in an arc surface shape (R surface shape) with a radius of 10 μm or more and the upper limit is a range that does not affect the flying posture of the head. Is.

A working example for working the thin film magnetic head 30 of this example will be described with reference to FIGS.

First, as shown in FIG. 3, the wafer to be the substrate 31 is processed into blocks, and then the MR element and the inductive head are processed into predetermined heights.

Next, as shown in FIG. 4A, a resist 34 is formed on the surface of the substrate block 31 in a slider shape.
Patterning is performed. The film thickness of the resist 34 is the radius of the arc surface shape of the slider corner portion × resist selection ratio ×
It is determined by the equation of 1.2, and the corners of the slider surface described later are formed in the best arcuate shape by this resist film thickness.

For example, when the R shape of the corner portion of the slider of the substrate block 31 is formed with a radius of 25 μm, the resist 34 to be used has a selection ratio of 6 for the resist 34 under the etching conditions used for the R shape processing. Wafer material Al ₂ O ₃ —TiC so as to form the substrate 31 to be formed
Is 1, the film thickness of the resist 34 is 25 × 6 ×
1.2 = 180 μm.

As described above, the shape of the corners of the pattern surface of the resist 34 matching the slider shape of the substrate block 31 is a shape in which the surfaces intersect at right angles as shown in FIG. 4B.

After patterning the resist 34 in accordance with the slider shape of the substrate block 31 as described above, the resist 34 is thermally cured at about 200 ° C. as shown in FIG. 5A. By thermally curing the resist 34, the resist 34 contracts as shown in FIG. 5B, and the corners 34a of the pattern surface of the resist 34 become arcuate surfaces.

In this state, the patterned surface of the resist 34 is etched by reactive ion etching which is dry etching as shown in FIGS.
The shape of the pattern surface is transferred to the surface of the substrate block 31 of Al ₂ O ₃ —TiC.

After that, when the resist 34 is peeled from the substrate block 31 as shown in FIG. 8 and FIG.
As shown in B of No. 3, the pattern of the resist 34 whose corners are formed into an arc surface (R shape) by heat curing is transferred, and the resist 3
The surface of the underlying portion, that is, the slider surface 31a in which 4 was present was the corners 31c ₁ , 31c ₂ , 31b ₁ , 3 of the four sides.
It becomes an R shape with the corners of 1b ₂ removed.

On the slider surface 31a of the substrate block 31 thus formed, as shown in FIG.
A resist 35 for forming the S pattern 32 is patterned with a groove pattern and then etched.

After etching with the groove pattern of the resist 35, the resist 35 is peeled off.
As shown in FIG. 11, the slider surface 31a on which the ABS pattern surface 32 is formed is formed. Since so-called two-step digging is currently the mainstream in forming the slider surface 31a, another groove is needed to perform this two-step digging. In this case, the groove pattern formed by the resist 35 is used. Patterning and etching are performed, and the subsequent peeling operation of the resist 35 is repeated once again.

As described above, the thin film magnetic head 30 having the slider surface 31a having the ABS pattern 32 of the required shape as shown in FIG. 2 is formed.

In the manufacturing process of the thin film magnetic head 30 described above, the etching conditions in the step of forming the corners of the slider surface 31a of the substrate block 31 into the R shape are, for example, work prebaking at 75 ° C. for 20 minutes. Apply resist. The exposure is performed at 0.7 sec / Shot. Development is carried out in a 1% calcium carbonate solution. Post bake is performed at 200 ° C. for 20 minutes. Etching etching power 750V / 600m
A (etching rate 28 μm / Min) and etching time 1 minute. The resist is stripped by ultrasonic cleaning with ethanol for 10 minutes.

The thin-film magnetic head 30 formed as described above forms the R shape only at the corners of the slider surface 31a of the substrate block 31, so that the above-described processing of the substrate block 31 is not performed for each block. Also, it is possible to process in a series of bars, which can greatly improve the production efficiency.

The thin film magnetic head 3 formed as described above.
In the case of 0, only the corners of the slider surface 31a of the substrate 31 are formed in an R shape, so that the influence on the shape of the ABS pattern surface 32 of the slider surface 31a is small, and there are few restrictions on the levitation design. Further, during processing of the thin film magnetic head 30, there is little risk of contact with the ABS pattern surface 32 of the slider surface 31a, head reliability can be improved, and mounting on a removable HDD or the like that requires impact resistance. Is advantageous in.

Further, the thin film magnetic head 30 has the substrate 3
Since the corner portion of the slider surface 31a of No. 1 has an R shape, a chipping or the like occurs in a mounting process to a head suspension which is a post process, that is, a handling in a head gimbal assembly (HGA) or a head suspension assembly (HSA). It is possible to prevent the occurrence of defects.
Further, there is an effect that there is no risk of the head being damaged by an external impact.

The embodiment of the present invention has been described above.
The present invention is not limited to this embodiment, and various modifications can be made without departing from the spirit of the present invention.

For example, the shape of the substrate block and the ABS pattern on the slider surface can be arbitrarily changed. Further, the configurations of the MR head and the inductive head can be arbitrarily changed.

When a block of a substrate is formed by cutting a series of bar-shaped substrates into a desired size, a plurality of bar-shaped substrates are cut into a plurality of blocks by a cutting machine such as a lathe machine equipped with a plurality of cutters. Can be cut and divided into blocks at the same time. Various cutting machines can be used for forming the substrate block.

[0051]

As described above, according to the present invention, since the corners of the slider surface of the substrate of the thin-film magnetic head are formed into an R shape by etching, there is a risk of contact with the ABS surface of the slider surface during processing. Since the slider surface of the substrate can be accurately formed over the entire surface including the ABS surface, the reliability of the thin film magnetic head is improved.

Further, since the corners of the slider surface of the substrate of the thin film magnetic head are formed in an R shape, it is advantageous in mounting on a removable HDD or the like which requires impact resistance. In addition, since the corners of the slider surface of the substrate have an R shape, a mounting process to a head suspension, which is a post process, that is, a head gimbal assembly (HGA) or a head suspension assembly (HS) is performed.
It is possible to prevent defects such as chipping from occurring in the handling in A), and there is no risk of damage to the head substrate due to external impact.

Further, the R-shaped formation of the corner portion of the substrate slider surface can be processed in a series of bar states, and has an effect that the production efficiency can be greatly improved.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram (cross-sectional view) of a thin film magnetic head applicable to the present invention.

FIG. 2 is a slider side perspective view of a thin film magnetic head of an example of the present invention.

3 is a conceptual perspective view of a substrate block after completion of height processing in a processing step of the thin film magnetic head shown in FIG.

4A is a conceptual perspective view of a state where a resist pattern is formed on the substrate block shown in FIG. 3 in accordance with a slider shape, and B is a partially enlarged perspective view.

5A is a conceptual perspective view of a substrate block in which the resist of the substrate block on which the resist pattern shown in FIG. 4 is subjected to thermal curing is set, and B is a partially enlarged perspective view.

6A is a conceptual perspective view of the substrate block showing a state where the substrate block obtained by thermosetting the resist shown in FIG. 5 is subjected to ion etching.

FIG. 7 is a conceptual perspective view of one substrate block in the ion etching state shown in FIG.

8 is a conceptual perspective view showing a state where the resist of the substrate block after the ion etching shown in FIG. 6 is removed.

9A is a conceptual perspective view of one substrate block in a state where the resist shown in FIG. 8 is removed, and B is a partially enlarged perspective view.

10 is a conceptual perspective view of the substrate block shown in FIGS. 8 and 9 in which a resist having a groove pattern is patterned.

11 is a conceptual perspective view of a substrate block in which an ABS pattern is formed by ion-etching the substrate block on which the resist patterning shown in FIG. 10 is performed and then removing the resist.

FIG. 12 is a perspective view showing an arrangement relationship between a thin film magnetic head and a hard disk.

FIG. 13 is a schematic diagram showing a contact relationship between a thin film magnetic head and a hard disk.

FIG. 14 is a schematic view of a conventional thin film magnetic head processing step, showing a state in which a head chip is clamped on a processing axis.

FIG. 15 is a schematic view of a process of processing a conventional thin film magnetic head, showing a state in which a head chip is polished.

[Explanation of symbols]

30 ... Thin-film magnetic head, 31 ... Substrate, 31a ... Slider surface, 31b ₁ , 31b ₂ , 31c ₁ , 31c ₂
... Arc surface corners, 32 ... ABS pattern surface, 34,
35: Resist

Claims (5)

[Claims] 1. A thin film magnetic head constituting a flying head which is supported by a suspension and which floats and opposes a recording surface of a rotating magnetic recording medium while keeping a predetermined distance. Is a thin-film magnetic head in which each corner of the slider surface facing the recording surface of the magnetic recording medium is formed in an arc surface shape. 2. The thin film magnetic head according to claim 1, wherein the thin film magnetic head has a configuration in which a corner is formed over the entire peripheral edge of a slider surface facing the recording surface of the magnetic recording medium. Magnetic head. 3. The thin film magnetic head according to claim 1, wherein the thin film magnetic head patterns a resist on a slider surface facing a recording surface of the magnetic recording medium,
By shrinking the resist due to heat curing, the corners of the resist surface are formed into an arc surface shape, and the shape of the resist surface is transferred by dry etching using this resist surface as a mask. 2. A method of manufacturing a thin film magnetic head, characterized in that the entire periphery of the above is rounded. 4. The method of manufacturing a thin film magnetic head according to claim 3, wherein the dry etching for etching using the resist patterned on the slider surface as a mask is reactive ion etching. Production method. 5. The method of manufacturing a thin film magnetic head according to claim 3, wherein the thickness of the resist for patterning the slider surface is: radius of arc surface shape of corner of slider surface × resist selection ratio × 1.2. A method of manufacturing a thin-film magnetic head, characterized by being determined by a formula.