JPH1186485A - Thin film magnetic head slider - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a slider having the stable floating property even through the chipping is generated at the flowing out end, and also having the fine CSS property without increasing the number of processes. SOLUTION: Rails 83, 84 in the longitudinal direction are formed at both sides of an ABS surface of the slider 80, and a rail 85 in the lateral direction connected between these rails 83, 83 is formed. Cavity parts 86, 87 etched to a specified thickness by the ion milling process are formed between both of the rails 83, 84. Notched parts 83b, 84b for air escape having the thickness equal to that of the cavity part 86 are formed at the rear end parts of the rails 83, 84 in the longitudinal direction. Thus, even through the chipping is generated at the rear end part of the ABS surface for some reason or other, this chipping is not brought into contact with a magnetic record medium, therefore, the magnetic record medium is prevented from being damaged.

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 a magnetic disk drive or the like, and more particularly to a slider air having a flying surface formed by forming a rail of a predetermined shape on a surface facing a magnetic recording medium. The present invention relates to a thin-film magnetic head slider having a thin-film magnetic head element formed on an outflow end side.

[0002]

2. Description of the Related Art A thin film magnetic head has a thin film magnetic head element formed on a rear end surface of a ceramic block called a slider, and a surface of the slider facing a magnetic recording medium, that is, an ABS (Air Bearing Surface). In (), a rail having a predetermined shape is formed. For this reason, when the magnetic recording medium rotates, the slider is given a lifting force by the high-speed airflow flowing from the tapered portion at the front end of the rail, and maintains a gap of about 0.1 μm from the surface of the magnetic recording medium. The head floats so that the head tip does not directly contact the magnetic recording medium.

As described above, since the ABS surface of the slider lands on the recording surface of the magnetic recording medium in a close contact state when the magnetic recording medium is stopped, a large starting torque is required for the motor at the time of starting. Since the recording surface of the magnetic recording medium may be damaged, the slider ABS
A tapered portion is formed on the air inflow side (the front part in the rotation direction of the magnetic recording medium) of the surface. On the other hand, the rear end of the ABS surface of the slider of the flying magnetic head is an air outflow end.

Normally, this type of slider is formed by stacking a number of thin-film magnetic head elements on a ceramic wafer, cutting the wafer into a rod, and processing the rod as shown in FIG. As shown in the figure, longitudinal rails 93 and 94 are provided on both sides of the ABS (Air Bearing Surface), and these rails 93 and 94 are provided.
A slider 90 is obtained with a lateral rail 95 connected between them. In addition, tapered portions 93a and 94a are formed at the front portions of the vertical rails 93 and 94.
A cavity 9 is etched between the rails 93 and 94 to a predetermined thickness by ion milling.
6,97 are formed.

[0005]

However, the rails 93, 9 on the ABS surface of the magnetic head slider 90 described above.
When the rear end of the slider 4 is an air outflow end, the magnetic recording medium D is rotationally driven to generate a positive pressure on the rails 93 and 94 on the ABS surface, and a negative pressure on the cavity 96 to generate a slider. When the head 90 flies above the magnetic recording medium D, the air inflow side of the slider 90 (93a, 94a)
This causes a so-called pitch in which the flying height is larger than that on the air outflow side. As shown in FIG. 10B, the minimum floating position on the ABS surface of the slider is the air outflow end Z.

Normally, in this type of thin film magnetic head, it is important for the recording / reproducing characteristics that the gap portion G of the thin film magnetic head element be at the minimum flying position. The flying characteristics become unstable, and the sensitivity of the recording / reproducing signal changes, making it impossible to read the data recorded on the magnetic recording medium D accurately, or A problem that the data cannot be recorded on the disc. In addition, there has been a problem that the CSS (Contact Start Stop) characteristic is deteriorated in that the coefficient of friction between the slider 90 and the magnetic recording medium caused by the repetition of flying and stopping of the slider 90 is increased.

Further, as shown in FIG.
If a chip 93b is formed at the outflow end of 0, the outflow of air changes, and the flying characteristics of the slider become unstable, resulting in a problem that the sensitivity of the recording / reproducing signal changes. Since the edge of the notch 93b is sharp, when the edge of the notch 93b comes into contact with the magnetic recording medium D, the contact surface of the magnetic recording medium D may be damaged, or fragments may be scattered on the magnetic recording medium D. Was. Therefore,
The present invention has been made in view of the above problems,
An object of the present invention is to provide a slider having stable flying characteristics and good CSS characteristics without increasing the number of steps even if a chip occurs at an outflow end.

[0008]

SUMMARY OF THE INVENTION The present invention relates to a thin-film magnetic head formed on a surface of a slider having a floating surface by forming a rail having a predetermined shape on a surface facing a magnetic recording medium. A thin-film magnetic head slider on which an element is formed.
Is characterized in that an air escape cutout is provided at the rear end of the rail on the air outflow end side. If such a notch for air release is provided at the rear end of the rail on the air outflow end side, even if the rear end of the ABS surface is chipped, this notch may not contact the magnetic recording medium. The magnetic recording medium can be prevented from being damaged.
There is no adverse effect on the S characteristics. Further, since the pressure of the air escape notch is substantially equal to the atmospheric pressure, AB
Even if the rear end of the S surface is chipped, the flying characteristics of the slider are not adversely affected.

A second feature of the present invention is that the depth of the above-described cut-out portion for air release is made equal to the depth of a cavity portion for generating negative pressure other than the rail portion, and the cavity portion is formed. At the same time, a notch for air release is formed. If the thickness of the air escape notch is made equal to the thickness of the cavity as described above,
Since the air escape notch can be formed at the same time when the cavity is formed in the ion milling process, it can be formed without increasing the number of steps simply by changing the pattern shape of the photomask. It becomes possible.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a thin-film magnetic head slider according to the present invention will be described below with reference to FIGS. FIG. 1 is a diagram schematically showing a magnetic head wafer in which a plurality of thin film magnetic head elements are formed in a vertical direction and a horizontal direction by a wafer process.
FIG. 2 is a view showing a state in which an element row of a magnetic head wafer is cut into blocks of a plurality of rows in a slicing process. FIG. ABS of lower element row
FIG. 4 is a diagram illustrating a state in which a surface (Air Bearing Surface) is polished (wrapped). FIG. 4 is a diagram illustrating a state in which an element row after lapping is cut. FIG. FIG. 6 is a diagram showing a series of steps from photo etching to ion milling for forming a rail on the ABS surface of one element row.

1. The thin film magnetic head element manufacturing process AlTiC (Al ₂ O ₃ -TiC) wafer process ceramic substrate made of a thin film magnetic head element (GMR head) for reproduction. Thereafter, a lower magnetic layer is formed on the film surface on which the reproducing thin-film magnetic head element is formed, and then an alumina (Al ₂ O ₃ ) film having a thickness of about 1 μm corresponding to the gap length is formed by sputtering. I do. At this time, an alumina film should not be formed on a portion directly in contact with an upper magnetic layer to be formed later. Next, a photoresist is applied to the coil forming region, and is then cured by heating. The cured photoresist itself is used as an insulating layer itself, and has a function of flattening a step between the lower magnetic layer and the substrate.

A copper coil is formed on the photoresist, the photoresist is applied again, and then heated and hardened to form an insulating layer and to flatten the surface step due to the coil, and an upper magnetic layer is formed thereon. To form a write (recording) thin film magnetic head element (inductive head). Next, after forming pad portions (terminal portions) on these portions, an alumina film is formed on the thin-film magnetic head element to protect the thin-film magnetic head element.

2. Block cutting step The magnetic head wafer 10 thus formed is
As shown in FIG. 1, a plurality of thin-film magnetic head elements are formed on the surface 10a so as to form element rows 11, 12, 13,... In the vertical direction. For example, the thin-film magnetic head elements 11a, 11b, 11c
.. Are formed in large numbers. Note that the element rows 12, 13
Is the same.

As described above, the thin-film magnetic head elements 11a, 11a,
11b, 11c... Are vertical element rows 11, 12, 1
.. Formed on the magnetic head wafer 10 as a plurality of rows (for example, 10 rows).
2 as a block, as shown in FIG. 2, a plurality of blocks 20, 30, 40,... (FIG. 2 shows only the blocks 20, 30, 40, but actually, a large number of blocks (for example, 10 Cut into blocks). Thus, when the magnetic head wafer 10 is cut for each of the blocks 20, 30, and 40,
Nos. 0 and 40 are cut while maintaining the high straightness of the magnetic head wafer 10, and each of the cut blocks 2
Since 0, 30, and 40 have much higher rigidity than one element row, the blocks 20, 30, and 40 have high straightness.

One block, for example, the block 20 cut in this way is composed of element rows 21, 22,..., And the element row 21 (the same applies to the element rows 22. Elements 21a, 21b, 22c
・ ・ Is formed. Then, this block 20 (3
The side surface 20a (30a, 40a) of (0, 40) becomes an ABS (Air Bearing Surface), and the side surface 20b (30).
(b, 40b) is the back surface with respect to the ABS surface. In the subsequent steps, only the block 20 will be described to simplify the description.

3. Lapping Step The block 20 manufactured as described above is placed on the mounting surface of the work holder (jig) 50 as shown in FIG. 3, and the end of the block 20 and the mounting surface of the work holder 50 are rosin-bonded. Adhesion is performed with an adhesive 51 such as a system wax. At this time, the rear surface of the lowermost element row of the block 20 becomes the bonding surface, that is, the ABS surface of the uppermost element row of the block 20 becomes the upper end face,
0 is adhered on the mounting surface of the work holder 50.

Thereafter, the work holder 50 is rotated so that the block 20 adhered to the work holder 50 faces downward, and is placed on a lapping machine 60 as shown in FIG. Then, the lapping machine 60 is rotated while the polishing abrasive grains 62 made of diamond 0.5 μm or the like accommodated in the polishing abrasive grain container 61 are sprayed onto the lapping board 60 by the pump 63, and the lowermost element row of the block 20 is rotated. AB
Polish (lapping) the S surface. At the time of this lapping, as shown in FIG.
(Line) to a lapping target position (β line in FIG. 5). The γ-ray in FIG. 5 is a reference line for the element height, and the height from the β-ray to the γ-ray is the element height (for example, 1 μm, and in the case of an MR head, the height of the MR element).

4. Element Row Cutting Step After lapping the ABS surface of the lowermost element row of the block 20 so as to have a predetermined element height, the work holder 50 is removed from the lapping machine 60, and as shown in FIG. Is turned sideways, and the wrapped element row 21 is cut by rotating a cutting blade (not shown) so that the ABS surface has a predetermined element height.

In this way, when the ABS surface of the lowermost element row of the block 20 is wrapped so as to have a predetermined element height, the rigidity of the block 20 is greater than that of a single row of elements. Since the straightness is large, the ABS surface becomes uniform, and the lapping can be performed efficiently. Further, if the ABS surface is uniform, the element height of this element row is also uniform, so that lapping with a good yield can be performed.

[5] Iterative process In this way, by cutting the element row 21 wrapped so that the ABS surface has a predetermined element height, the block 20 is shortened by the length of the element row 21 cut. Next, the work holder 50 to which the block 20 thus shortened is adhered is placed on the lapping machine 60 again, and the polishing grinder made of diamond 0.5 μm or the like stored in the polishing grain container 61 is used. Pump the grains 62
3, the lapping machine 60 is rotated while spraying on the lapping machine 60 to wrap the ABS surface of the lowermost element row 22 of the shortened block 20, and the element height of the element row 22 becomes a predetermined height. Lapping process.

After lapping the ABS surface of the element array 22, the work holder 50 is removed from the lapping machine 60, the work holder 50 is turned sideways, and the element array 22 is cut in the same manner as when the element array 21 is cut.

Such lapping and element row cutting processing are repeated, and the remaining element row of the block 20 becomes 1
When the rows are aligned, the last lapping is performed, and the lapping and cutting of the block 20 are completed. Similarly, lapping and cutting are performed on the blocks 30, 40,... So that the ABS surface of each element row has a predetermined element height.

Next, the ABS of each element row is
Each of the element rows 21, 22... Wrapped so that the surface has a predetermined element height is attached to the work holder 50 so that the ABS surface is an adhesive surface, that is, the back surface is a wrapped surface. Glued and A
In the same manner as the lapping of the BS surface, each of the element rows 21 and
Wrapping is performed on the back surfaces of 2,. In this case, it is necessary to perform the lapping process on the back surface so as to generate a residual compressive stress that substantially balances the residual compressive stress generated by the lapping process on the ABS surface.

After the element rows 21, 22,... Wrapped so that the ABS surface has a predetermined element height, are sequentially cut into element rows 21, 22,. By wrapping the back surfaces of the rows 21, 22, ..., respectively, as shown in FIG.
A plurality of thin film magnetic head elements 21a, 21b, 21c,
An element row 21 having 21d, 21e, and 21f (the same applies to other element rows) is manufactured. In addition,
In FIG. 5, the thin-film magnetic head elements 21a, 21b,
Although six pieces 21c, 21d, 21e, and 21f are shown, the number is determined when the magnetic head wafer 10 is manufactured, and may be any number.

6. Resist Film Sticking Step The element array 21 manufactured as described above is placed on a strip-shaped work 70 as shown in FIG. Then
A milling resist film 71 is adhered to the ABS of the element array 21 placed on the work 70. The milling resist film 71 is made of a photosensitive resin, and is formed of a negative photosensitive resin that is hardly dissolved even when immersed in a developer (for example, an aqueous solution of sodium hydroxide (NaOH)) when exposed to ultraviolet rays. As the photosensitive resin, a positive photosensitive resin which is easily melted when immersed in a developer by being irradiated with ultraviolet rays may be used.

7. Exposure Step Next, as shown in FIG. 6B, the A of the element row 21 in which the milling resist film 71 is stuck on the ABS surface.
A photomask 72 on which a predetermined rail-shaped pattern is formed is placed on a BS surface (Air Bearing Surface), and ultraviolet rays are irradiated onto the photomask 72 from an ultraviolet lamp 73 disposed above the photomask 72. When the photomask 72 is irradiated with ultraviolet light, the ultraviolet light that has passed through the photomask 72 on which the predetermined rail-shaped pattern is formed exposes the milling resist film 71 to the predetermined rail-shaped pattern. UV-sensitive portions 71a, 71b, 71 of milling resist film 71
c, 71d, 71e, and 71f are cured, and a developing solution (for example, sodium hydroxide (NaOH)
(Aqueous solution).

8. Developing Step Next, the element array 21 in which the milling resist film 71 is exposed to a predetermined rail-shaped pattern is immersed in a developing solution (for example, an aqueous solution of sodium hydroxide (NaOH)).
The exposed portion 71 of the milling resist film 71
The milling resist film 30 other than a, 71b, 71c, 71d, 71e, and 71f is removed by dissolving it in a developing solution (for example, an aqueous solution of sodium hydroxide (NaOH)).

9. Ion Milling Step Next, as shown in FIG. 6C, portions 71a, 71b, 71c, 71d, and 7 exposed to a predetermined rail pattern.
Ion milling is performed by irradiating argon ions Ar ⁺ on the ABS surface of the element row 21 where 1e and 71f remain. By this ion milling, as shown in FIG.
The portions 21g, 21h, 21i, 21j, 21j, 21j, of the ABS surface other than the portions 71a, 71b, 71c, 71d, 71e, 71f where the milling resist film 71 on the BS surface remains
21k, 211, and 21m are etched into grooves to form rail patterns as shown in FIGS.

10. Slider manufacturing process Each thin-film magnetic head element 21 is formed by an ion milling process.
a, 21b, 21c, 21d, 21e, 21f ABS
After cleaning the element row 21 having a predetermined rail shape with a cleaning liquid to remove the milling resist film 71,
Each thin-film magnetic head element 21a, 21b, 21c, 21
When cutting is performed for each of d, 21e, and 21f, a slider 80 having a rail pattern as shown in FIGS. 7 and 8 is obtained. FIG. 7 is a perspective view schematically showing the slider 80 manufactured as described above, FIG. 8A is a top view thereof, and FIG. 8B is a part A in FIG. 8A. It is an enlarged view, FIG.8 (c) has each shown BB sectional drawing of FIG.8 (b).

11. Structure of ABS Surface of Slider As shown in FIGS. 7 and 8, the slider 80 of the present embodiment has alumina (Al ₂ O ₃ ) on the surface of the rear end of an Altic (Al ₂ O ₃ —TiC) substrate 81. A thin film magnetic head element (GMR head) for reproduction and a thin film magnetic head element for writing (inductive head) (not shown) (not shown) are provided in the alumina (Al ₂ O ₃ ) film 82.
7 and 8 show only the gap portion (G) of both heads).

The ABS of this slider 80 (Air Bear
ing Surface) has vertical rails 83,
A lateral rail 85 connected between the rails 83 and 84 is formed. In addition, tapered portions 83a and 84a are formed at the front portions of the vertical rails 83 and 84. Cavity portions 86, 87 etched to a predetermined thickness by an ion milling process are formed between both rails 83, 84. At the rear ends of the vertical rails 83 and 84, air escape cutouts 83b and 84b having the same thickness as the cavities 86 are formed.

When the slider 80 on which the ABS is formed floats above the magnetic recording medium D, as shown in FIG. 9, the air escape notch 83b (the air escape notch 84b).
The same applies to b). The X part at the end of the end portion is the minimum flying distance with respect to the magnetic recording medium D. Thus, by providing the air escape notches 83b and 84b, the rear end Y of the ABS surface without the air escape notches 83b and 84b is higher than the minimum flying distance with respect to the magnetic recording medium D. Thus, the vicinity of the gap (G) becomes the minimum flying distance.

Therefore, even if the rear end of the ABS surface is chipped for some reason, this chipping is caused by the magnetic recording medium D.
As a result, the magnetic recording medium can be prevented from being damaged, and the CSS characteristics are not adversely affected. Further, since the pressure of the air escape notches 83b and 84b is substantially equal to the atmospheric pressure, even if the rear end of the ABS surface is chipped, the floating characteristics of the slider 80 are not adversely affected. Further, since the thickness of the air escape notches 83b and 84b is made equal to the thickness of the cavities 86 and 87, the air escape notches 83b and 84b form the cavities 86 and 87 in the ion milling process. Since the photomask is formed at the same time, the photomask can be formed simply by changing the pattern shape of the photomask without increasing the number of steps.

[Brief description of the drawings]

FIG. 1 is a diagram schematically showing a magnetic head wafer.

FIG. 2 is a diagram showing a state where a magnetic head wafer is cut into blocks.

FIG. 3 is a diagram showing a state in which the ABS surface of the element row at the bottom of the block is wrapped.

FIG. 4 is a diagram showing a state in which an element row after lapping is cut;

FIG. 5 is a diagram showing one cut element row.

FIG. 6 is a diagram showing a series of steps from a step of photo-etching an ABS surface of one element row to a curing processing step.

FIG. 7 is a perspective view showing a schematic configuration of an embodiment of the thin-film magnetic head slider of the present invention.

8 is a diagram showing a main part of FIG. 7, FIG. 8 (a) is a top view of FIG. 7, and FIG. 8 (b) is an enlarged view of a portion A of FIG. 8 (a). FIG. 8 (c) is BB of FIG. 8 (b).
It is a figure showing a section.

FIG. 9 is a diagram showing a state where the thin-film magnetic head slider of FIG. 7 floats above the magnetic recording medium.

FIG. 10 is a view showing a conventional thin film magnetic head slider.

11 is a diagram showing a state in which a rear end portion of the thin-film magnetic head slider of FIG. 10 is chipped.

[Explanation of symbols]

10 ... magnetic head wafer, 11a, 11b, 11c ...
Thin-film magnetic head elements, 20, 30, 40... Element row blocks, 21a, 21b, 21c.
80: thin-film magnetic head slider, 81: substrate, 82: alumina film, 83, 84, 85 ... rail, 86, 87 ... cavity, 83a, 84a ... air escape cutout

Claims (2)

[Claims] 1. A thin film magnetic head slider wherein a thin film magnetic head element is formed on an air outflow end side of a slider having a predetermined shape formed on a surface side facing a magnetic recording medium and formed as a flying surface, A thin-film magnetic head slider comprising an air escape cutout at the rear end of the rail on the air outflow end side. 2. The depth of the air escape notch is equal to the depth of a negative pressure generating cavity other than the rail, and the air escape notch is formed at the same time as the cavity is formed. 2. The thin film magnetic head slider according to claim 1, wherein the slider is formed.