JP3108509B2 - Method for manufacturing thin-film magnetic head - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a thin-film magnetic head, and more particularly, to a diamond polishing method in which an abrasive layer having diamond fine particles as abrasive grains is supported by a flexible film as a support. The present invention relates to a method of manufacturing a thin film magnetic head for polishing a slider of a thin film magnetic head with a film.

[0002]

2. Description of the Related Art With an increase in information recording capacity and high-speed access, there is an increasing demand for a thin film magnetic head having a higher magnetic permeability than a ferrite head and capable of maintaining a high electromagnetic conversion even at a high transfer rate. ing.

In a thin film magnetic head, various ceramic substrate materials are required for a slider, and SiC, Zr
Materials such as O ₂ , Al ₂ O ₃ and Al ₂ O ₃ —TiC are used for the slider.

The slider of the thin-film magnetic head is polished on the surface of the air bearing surface of the medium facing surface in order to obtain stable flying performance and good running durability, and furthermore, the end portion and the peripheral ridge angle. It is necessary to chamfer the part. When polishing the air bearing surface of the slider, for example, Japanese Patent Application Laid-Open Nos. 60-185272 and 63-70918
JP-A-2-199614, JP-A-2-199614
As disclosed in JP-A-12057 and JP-A-2-301014, a polishing tape or a polishing film is used.

In the polishing of various ceramic materials, processing with a diamond polishing film using diamond particles is required in order to improve polishing workability. However, although the above publication does not disclose processing using a diamond polishing film, polishing of a thin film magnetic head using a diamond polishing film has been conventionally performed.

[0006]

However, when the slider is polished with the above-mentioned conventional diamond polishing film, even if the slider is polished under the same conditions, small chamfering is difficult, or the chamfer dimensions and angles are uneven. It has been found that the corner may be formed at the transition portion between the straight portion and the chamfered portion. As described above, if the chamfering process cannot be made small, it cannot be used with a small slider, and if the chamfer dimensions or the chamfer angle vary, for example, a floating magnetic head cannot guarantee a predetermined durability. It becomes impossible to fly at a stable relative speed and flying height, and if the polished surface has an angle as described above, the medium is damaged, and the flying or running property is adversely affected.

Accordingly, the present invention can perform extremely small chamfering with high precision, can continuously and smoothly chamfer the adjacent surfaces, and can minimize the amount of chamfering. It is a main object of the present invention to provide a method of manufacturing a thin film magnetic head capable of obtaining a head exhibiting stable flying characteristics.

[0008]

Means for Solving the Problems The present inventors have conducted intensive studies on the conventional problems, and found that in the conventional diamond polishing film, if the diameter of the diamond fine particles was too large and the polishing film was too strong, It has been found that the adhesion between the polishing film and the object to be polished is deteriorated, and the uniformity of the polished surface is affected.

The present inventors have further studied a diamond polished film in order to solve the adhesion between the diamond polished film and the object to be polished, and have found that the thickness of the film is largely dependent on the overall thickness.

[0010] The present invention has been made based on the above findings, and includes the following (1) to (6). (1) In a method of manufacturing a thin film magnetic head for polishing a slider of a thin film magnetic head with a diamond polishing film using diamond fine particles, the thickness of the diamond polishing film is set to 15 μm or less, and the average particle size of the diamond fine particles is reduced. Is set to 1.0 μm or less.

(2) The method of manufacturing a thin film magnetic head according to (1), wherein the thickness of the diamond polishing film is 10 μm or less.

(3) The method of manufacturing a thin film magnetic head according to the above (1) or (2), wherein the Vickers hardness HV (500 g) of the slider of the thin film magnetic head is set to 1100 or more.

(4) The method of manufacturing a thin-film magnetic head according to (1) or (2), wherein the Vickers hardness HV (500 g) of the slider of the thin-film magnetic head is set to 1500 or more.

(5) The method of manufacturing a floating magnetic head according to (1) or (2), wherein the Vickers hardness of the slider of the thin-film magnetic head is in the range of 1800 to 3000.

(6) After forming a plurality of thin-film magnetic transducers on a substrate, the thin-film magnetic transducers are cut, and the cut end face is used as the medium facing surface, and the thin-film magnetic transducer is polished with the diamond polishing film. 5) The method for manufacturing a thin-film magnetic head according to any one of 5).

[0015]

According to the present invention, by setting the diamond grain size and the total thickness of the diamond polishing film, it is possible to perform extremely small chamfering with high precision and to eliminate variations in chamfer dimensions and angles, thereby improving durability. And the magnetic head can fly at a stable relative speed.

[0016]

Preferred embodiments of the present invention will be described below with reference to the accompanying drawings. First, the thin-film magnetic head obtained by the present invention will be described. FIG. 1 is a perspective view showing an example of a thin-film magnetic head.
The medium facing surface 11 has a flat air bearing surface 111. In both figures, a indicates the air inflow direction when combined with a magnetic disk. In FIG. 1, two rails 16, 16 are formed at both ends of the medium facing surface 11 in the air inflow direction a via a groove 19 at the center, and the medium facing surface on the rails 16, 16 is formed. Constitute the air bearing surface 111. The number of rails 16 may be three or more.

When used as a magnetic disk drive,
A surface 12 opposite to the medium facing surface 11 of the slider 1 is head-stacked on a gimbal assay, and is started and stopped in this state. start. It is driven by a top (hereinafter referred to as CSS) method. When the magnetic disk is stationary, the air bearing surface 111 is pressed against the surface of the magnetic disk by the spring pressure of the head support device, but when the magnetic disk rotates, the lift dynamic pressure is applied to the air bearing surface 111 of the slider 1. Is generated, and the head operates at a flying height that is balanced with the dynamic pressure and the spring pressure of the head support device. Note that so-called dynamic loading may be used instead of CSS.

As shown in FIG. 1, the rails 16, 16
The ridge formed by the air bearing surface 111 and the side end surface 13 at the air inflow end side of the
It has a shape. For this reason, in the CSS operation or the like, the start can be easily performed, and the head crash, the medium damage, and the like hardly occur. That is, when the angle between the inclined surface 14 and the air bearing surface 111 on the air inflow end side forms a predetermined angle, and the length is set to a predetermined dimension, and the processing accuracy is increased, more stable operation is achieved. Ascent starts or stops at relative speed.

Such an inclined surface 14 is formed by chamfering by polishing. At this time, since the inclination angle is small, problems tend to occur in the accuracy of the surface dimensions and the inclination angle,
These precisions are significantly higher according to the invention. In the illustrated example, the ridge formed by the air bearing surface 111 and the side end surface 14 on the air outflow side of the rails 16, and both sides in the longitudinal direction of the sliders 16, 16 are inclined surfaces 17, 18. An example is shown.

The slider 1 has a Vickers hardness (JIS Z 2244, test load 500 g) HV (5
00g) It is set to be 1100 or more, especially 1100 to 3000. In this case, the lower limit is preferably 1300 or more, more preferably 15
00 or more, more preferably 1800 or more. At this time, the effect of the present invention is further improved.

As such a ceramic material, A
l ₂ O ₃ —TiO ₂ [HV (500) about 1150],
MgO-NiO-ZrO ₂ (about 1200), ZrO
₂ (about 1200 to 1600), ZrO ₂ —Al ₂ O ₃
(About 1400-1600), Al ₂ O ₃ -Tic-
AlN (1700-2000), SiC (1800-2)
000), Al ₂ O ₃ —TiC (2000 to 230
0) and the like are preferable. These may contain Mg, Y, ZrO ₂ , TiO _2, or the like as an additive.

Among them, those particularly suitable for the present invention are ceramics containing Al ₂ O ₃ —TiC as a main component in view of workability.

FIG. 4 is a diagram showing a method of manufacturing the magnetic head shown in FIG. In the figure, 1 is a magnetic head slider, 91 is an elastic sheet, 92 is a polishing film, 93 is a worktable, and 94 is a jig. In this case, the slider may have any of the above structures.

As shown in FIG. 5, the polishing film 92 is formed by forming an abrasive layer 921 on a flexible film 922 as a support. Abrasive layer 921
Can be produced by using, for example, synthetic diamond abrasive grains as diamond fine particles, using a binder resin such as a polyurethane resin, and applying and drying using a diluting solvent such as a MEK / toluene / cyclohexanone mixed system. The above paste is prepared using various coating machines.
It is uniformly coated on a support to form a layer. As the flexible film 922 as the support, polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyamide, polyimide, or the like can be used.

The average particle diameter of the diamond particles must be 1 μm or less, as will be understood from the following examples, but is particularly preferably 0.1 to 1.0 μm, more preferably 0.1 to 1.0 μm.
It is preferably 0.9 μm, most preferably 0.1 to 0.5 μm. The ratio between the diamond particles and the binder is about 1: 1/7 to 1 by weight. Also,
The thickness of the abrasive layer 921 is preferably 1 to 10 μm.

The magnetic head slider 1 is attached to a jig 94 by means such as bonding, and the medium facing surface 11 side of the slider 1 of the thin-film magnetic head is supported by an elastic film 91 while applying a load to the jig 94. The slider 1 is brought into contact with the surface of the
Is relatively moved with respect to the polishing. At this time, as shown in FIG. 4, the stiffness E, which is an index of the flexibility of the polishing film, whose Young's modulus is defined as E, so that the diamond polishing film is pressed in a suitable state.
T ³ is 0.5 to 3 × 10 ⁵ , especially 0.5 to 2 × 10 ⁵ ,
Furthermore, 0.8 to 1.2 × 10 ⁵ (μm) ³ Kg / mm
It is desirable to set it to ² . Since the flexible film as the support is formed of the above-described material, the stiffness of the diamond-polished film largely depends on its total thickness because the rubber hardness is within a certain range. Therefore, if the thickness of the polishing film is too thick or too thin, the adhesion deteriorates and the uniformity of the polished surface is lacking. Therefore, in the present invention,
By setting the thickness of the film to 15 μm or less, preferably 10 or less, and setting the stiffness of the diamond polishing film within the above range, the variation in the polished surface can be suppressed, and stable durability running can be obtained. Was.

The above relative movement may be achieved by any movement of the slider 1 and the polishing film 92. Alternatively, the polishing film may be formed in a circular shape, and the film may be rotated about the center of the circular shape and polished like a so-called buff. Also, a combination of a long polishing film and an elastic sheet, with the polishing film outside,
A loop may be formed to form an endless tape, which may be polished by running. The load is in the range of 5 to 200 g per magnetic head. The polishing time varies depending on the hardness of the slider 1, the particle size of the diamond particles, the magnitude of the load, and the like, but is generally about 10 to 300 seconds.

In this way, the air bearing surface 111
Besides polishing, for example, JP-A-60-185272, JP-A-63-70918, JP-A-2-199614, and JP-A-2-199614.
In accordance with the method described in JP-A-212057, JP-A-2-301014, etc., the slider 1 and the polishing film are inclined as necessary, or the polishing film is arranged in a predetermined shape, and the inclination angle and the angle of the ridge are adjusted. Beveling is performed.

As described above, in summary, the method of the present invention comprises diamond particles having an average particle size of 1.0 μm or less,
And a polishing film having a thickness of 15 μm or less, the main surface of which is to contact the medium facing surface side of the magnetic head slider and move the slider relatively to the polishing sheet to polish the medium facing surface. It is.

Next, in order to confirm the effect of the method of the present invention, particularly the effect of the polishing method, as shown in Table 1, the particle size of diamond as an abrasive was set. The paste was blended with the compounding ratio of the paste as shown in Table 1, the thickness was set as shown in Table 1, and the load and the polishing time were constant using a diamond polishing film arranged on a predetermined elastic sheet. Under the conditions described above, the sliders (magnetic heads) shown in FIG. Table 3 shows the results. The object to be polished is Al ₂ O ₃ -T
A thin-film magnetic head made of iO ₂ and having a slider of Hv (500 g) of 2000 was used. The polishing accuracy was determined by measuring various locations on the polished surfaces of the ten polished sliders and examining dimensional variations.

[0031]

[Table 1]

[0032]

[Table 2]

[0033]

[Table 3]

As is clear from these tables, when any one of the conditions of the thickness of the diamond polished film of 15 μm or less and the average particle diameter of the diamond fine particles of 1.0 μm or less is not satisfied, a variation larger than 5 μm occurs.
It can be seen that a large angle θ is formed between the chamfered surface and the horizontal and vertical surfaces, which is not practical. Thickness 15
At μm or less and at an average particle size of 1.0 μm or less, all of them are in a satisfactory state. In particular, if the thickness is 10
μm or less, and the average particle size is 0.1 μm or more,
It can be seen that when the thickness is 0.9 μm or less, particularly 0.5 μm or less, these are in a more preferable state.

Further, an experiment was conducted by changing the average particle diameter of the diamond fine particles used to 1.0 μm and changing the Vickers hardness HV (500 g) of the slider and the thickness of the diamond polishing film as shown in Table 4. Table 4 shows the results. As shown in Table 4,
It can be seen that when the Vickers hardness is less than HV (500 g) 1100, the polished surface is severely scratched and cannot be put to practical use. On the other hand, Vickers hardness HV (500
g) When it was 1100 or more, only a small scratch on the polished surface of the slider was satisfactory. When the Vickers hardness HV (500 g) is 1200 or less, if the total thickness of the diamond polished film is 10 μm or less, the generated scratches become minute.

In particular, when the Vickers hardness HV (500 g) is 1500 or more, both scratches and accuracy are in a good state, and when it is 1800 or more, very good results are obtained.

[0037]

[Table 4]

As can be seen from the above table, the Vickers hardness HV (500 g) is 1400 or more, and the total thickness is 7 μm.
When it was less than the above, the dimensional variation was 2 μm or less, which was satisfactory. Further, even when the total thickness is 7 μm as it is, the Vickers hardness HV (500 g) is 150 μm.
When the value is 0 or more, the dimensional variation is 0.5 μm or less, which is satisfactory. This tendency is improved as the Vickers hardness HV (500 g) becomes larger and as the total thickness becomes smaller, the accuracy improves. You can see that

[Brief description of the drawings]

FIG. 1 is a perspective view showing one example of a floating magnetic head manufactured by a manufacturing method of the present invention.

FIG. 2 is a front view of the magnetic head of FIG. 1;

FIG. 3 is a side view of the magnetic head of FIG. 1;

FIG. 4 is a front view for explaining a method of polishing the air bearing surface of the slider of the floating magnetic head.

FIG. 5 is a cross-sectional view showing one example of a polishing film used in the method of the present invention.

[Explanation of symbols]

 Reference Signs List 1 slider 11 medium facing surface 111 air bearing surface 14, 17, 18 inclined surface 92 polishing film 921 polishing material layer 922 flexible film

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. ⁷ , DB name) G11B 5/60 G11B 21/21

Claims (6)

(57) [Claims] 1. A method of manufacturing a thin film magnetic head for polishing a slider of a thin film magnetic head using a diamond polishing film using diamond fine particles, wherein the diamond polishing film has a thickness of 15 μm or less and an average of the diamond fine particles. Particle size 1.0μ
m. 2. The method of manufacturing a thin-film magnetic head according to claim 1, wherein the thickness of said diamond polishing film is 10 μm or less. 3. The method according to claim 1, wherein the slider of the thin-film magnetic head has a Vickers hardness HV (500 g) of 1100 or more. 4. The method of manufacturing a thin-film magnetic head according to claim 1, wherein the Vickers hardness HV (500 g) of the slider of the thin-film magnetic head is set to 1500 or more. 5. The method according to claim 1, wherein the slider of the thin-film magnetic head has a Vickers hardness in the range of 1800 to 3000. 6. A method according to claim 1, wherein a plurality of thin film magnetic transducers are formed on a substrate, and then cut, and the cut end face is used as a medium facing surface and polished with the diamond polishing film. Manufacturing method of such a thin film magnetic head.