JPH0877511A - Production of thin-film magnetic head - Google Patents

Abstract

PURPOSE: To decrease defective articles and to reduce a cost by drastically shortening the time for cylindrical polishing and air groove forming. CONSTITUTION: Plural thin-film magnetic head elements are formed on a wafer and thereafter this wafer is cut in such a manner that the thin-film magnetic head elements line up horizontally in one row, by which head element blocks 3 having a rectangular strip shape are cut out. Next, a protective substrate 4 is adhered onto the thin-film magnetic head element and an air groove 9 parallel with a magnetic gap (g) is formed on a surface 8 which is the medium- sliding surface of the head element block 4 adhered with this protective substrate 4, and simultaneously, the surface 8 which is the medium-sliding surface is polished to an arc shape. The surface 8 which is the medium-sliding surface is then subjected to cylindrical polishing until the prescribed curvature is attained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a thin film magnetic head used for a data cartridge drive used as an external storage device of a computer, for example.

[0002]

2. Description of the Related Art For example, a thin film magnetic head used for a data cartridge drive is manufactured as follows.

First, a plurality of thin film magnetic head elements are formed in several rows and several columns by a vacuum thin film forming technique on a substantially disk-shaped wafer.

Next, the wafer is cut so that a plurality of thin-film magnetic head elements are arranged in a horizontal row, and strip-shaped head element blocks are cut out. Then, as shown in FIG.
A protective substrate 102 is adhered to a surface 101a of the head element block 101 on which the thin film magnetic head element is formed so as to sandwich these thin film magnetic head elements. Protective substrate 1
The state where 02 is bonded is shown in FIG.

Next, as shown in FIG. 1C, the surface 103, which is the medium sliding surface, is cylindrically polished to have a predetermined curvature to obtain a predetermined gap depth. The cylindrical polishing is shown in FIG.
As shown in FIG. 5, the surface 103, which is the medium sliding surface, is pressed against the disk-shaped rotary grindstone 106 and moved in the direction indicated by arrow A in the figure.

Then, in order to secure the contact between the medium and the head and prevent the output from being lowered due to spacing loss, an air groove 105 is formed in the medium sliding surface 104. Air groove 1
In No. 05, a groove having a substantially U-shaped cross section is ground in the vicinity of the magnetic gap in parallel with the magnetic gap g.

[0007]

By the way, when performing the above-mentioned cylindrical polishing, it is necessary to hit the rotary grindstone 106 at the corners of the head element block 101 to which the protective substrate 102 is adhered. Therefore, it is easy to make a mistake in the hitting position, and it takes a very long time and psychological stress to check the hitting position.

[0008] Because the failure to hit the ball damages the work, in the worst case, the work and the rotary grindstone 1
This is because it also leads to the destruction of 06, which may cause physical damage to the processor.

Further, since the grinding speed of the cylindrical polishing is very slow, a slight difference in the grinding amount affects the processing time, but since the beginning of the contact between the work and the grindstone is the corner of the head element block 106, the entire surface is It takes time until the desired depth is obtained by grinding, which is a cause of prolonging the processing time.

Further, since it is necessary to perform air groove processing after the cylindrical polishing, it takes a long time to perform the cylindrical grinding and grooving processing in total, which causes a problem of cost increase during mass production. Was there.

Therefore, the present invention has been proposed in view of the above-mentioned problems of the prior art, and achieves a drastic reduction in cylindrical polishing and air groove formation time, and realizes reduction of defective products and cost reduction. An object is to provide a method for manufacturing a magnetic head.

[0012]

To manufacture a thin film magnetic head, first, a plurality of thin film magnetic head elements are formed on a wafer. Next, this wafer is cut to cut out strip-shaped head element blocks. Then, a protective substrate is bonded onto the thin film magnetic head element formed in the head element block. Then, a groove parallel to the magnetic gap is formed on the medium sliding surface of the head element block to which the protective substrate is adhered, and at the same time, the medium sliding surface is ground into an arc shape. Then, finally, the surface serving as the medium sliding surface is cylindrically polished to have a predetermined curvature to obtain a predetermined gap depth.

[0013]

In the present invention, since the medium sliding surface is also ground in an arc shape at the same time as the air grooving step, rough cutting is performed by this arc shape grinding, and the cylindrical polishing time in the final step can be shortened. Further, since the grooving and the grinding of the medium sliding surface are performed at the same time, the processing time can be greatly shortened and the cost can be reduced.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Specific embodiments to which the present invention is applied will be described in detail below with reference to the drawings.

In order to manufacture a thin film magnetic head, first, as shown in FIG. 1, a vacuum thin film forming means is used to form a substantially disk-shaped wafer 1 made of a nonmagnetic material such as Al ₂ O ₃ --TiC. A plurality of thin film magnetic head elements 2 are formed at a predetermined interval so as to form several rows and several columns.

As a thin film magnetic head used for a data cartridge, an inductive recording head having a coil formed so as to interlink with a core material having a relatively wide gap and an anisotropic magnetoresistive effect (AMR effect). Alternatively, it is configured by combining with a reproducing head utilizing a giant magnetoresistive effect (GMR effect). Here, as the thin film magnetic head element 2, a head in which the above recording and reproducing heads are combined is manufactured. In addition to the recording / reproducing head, either a recording head or a reproducing head may be manufactured.

In manufacturing the thin film magnetic head element 2, SiO ₂ , Al ₂ O ₃ , core material,
A conductor material or the like is sputtered to form a film, which is manufactured using a pattern forming method such as photolithography, etching, or plating.

Next, the wafer 1 is cut so that the thin film magnetic head elements 2 are arranged in a horizontal row, and the strip-shaped head element block is cut out. A cutting wheel is used for cutting.

Next, as shown in FIG. 3A, a protective substrate 4 is formed on the surface 3a of the cut head element block 3 on which the thin film magnetic head element 2 is formed so as to cover the thin film magnetic head element 2. Bond with resin adhesive.

Although not shown in FIG. 3 (a), in practice, the head element block 3 has reinforcing plates 5 and 6 bonded and fixed to both side surfaces thereof, as shown in FIG. When adhering the reinforcing plates 5 and 6 and the protective substrate 4 to the head element block 3, the reinforcing plates 5 and 6 are attached to the reference surface 7 shown in FIG.
6, the protective substrate 4 and the head element block 3 are pressed and positioned to be bonded.

As a result, as shown in FIG. 3B, the head element block 3 and the protective substrate 4 are adhered so that the thin film magnetic head element 2 is sandwiched.

Next, the head element block 3 to which the protective substrate 4 is adhered is set on the slicing machine,
As shown in (c), an air groove 9 parallel to the magnetic gap g is formed on the surface 8 to be the medium sliding surface, and at the same time, the surface 8 to be the medium sliding surface is ground into an arc shape.

The air groove 9 is formed for the following reason. Since the medium and the head operate at a very high relative speed, the minute projections and the like of the medium cause spacing when air is entrained, which adversely affects the contact between the medium and the head, resulting in comprehensive magnetic recording and It will reduce the playback capacity. In order to reduce this effect, the contact pressure between the head and the medium is reduced to increase the surface pressure. For that purpose, it is necessary to form grooves on both sides of the magnetic gap g in parallel with the track direction of the magnetic gap g. For this reason, the air groove 9 is formed on the medium sliding surface.

Here, the air groove 9 has a magnetic gap g.
And a straight groove having a substantially U-shaped cross section in parallel with the magnetic gap g. At the same time when the air groove 9 is formed, the surface 8 to be the medium sliding surface is ground, but here, rough cutting is performed by cylindrical polishing in the final step until it becomes a curvature shape that is approximately close to the desired curvature.

The grindstone 10 used in this step is a disk-shaped rotating grindstone as shown in FIG. Since the grindstone 10 has the shape of an arc having a curvature close to that of the medium sliding surface of the final product, as shown in FIG. And a pair of blades 1 for forming an air groove 9 in the central portion thereof.
2 are provided.

Using this grindstone 10, as shown in FIG. 3C, an air groove 9 is formed on the surface 8 which becomes the medium sliding surface, and at the same time, the surface 8 which becomes the medium sliding surface is made into an arc shape. Grind. At this time, since the grindstone 10 has an arc shape having a curvature that is almost similar to the medium sliding surface on which the final product is raised,
The hitting out can be performed more safely and surely than when the conventional method is used. Also, since the grinding stroke is shortened, this processing can be completed in a shorter time. In particular, if such an amount is used for cylindrical polishing at a low processing speed, a considerable amount of time is required, but since grinding is performed, processing can be performed in a short time.

Finally, the surface 8 to be the medium sliding surface is cylindrically polished so as to have a predetermined curvature, and the gap depth of the magnetic gap g is set to a predetermined value. In the cylindrical polishing, as shown in FIG. 8 described above, the head element block 3 to which the protective substrate 4 is adhered is tilted in the direction indicated by the arrow A, and is polished by the rotary grindstone 106.

At this time, since the surface 8 serving as the medium sliding surface is formed in an arc shape close to a predetermined shape in the previous step, the contact is not an angle but an arc portion, and the contact can be performed safely and reliably. In addition, since the polishing stroke may be short, the medium sliding surface 13 having a predetermined curvature can be obtained with a slight amount of polishing. Therefore, this cylindrical polishing processing time can be completed in a short time, and by shortening the polishing time, it is possible to reduce costs and suppress the generation of defective products.

Further, the effects of the present invention become remarkable in the following cases. When the apex of the circle of the medium sliding surface obtained by grinding is different from the center of the entire block in the above-mentioned example and is deviated from the center to some extent, and the width of the medium sliding surface with respect to the width of the entire block. When the curvature is small, the effectiveness of the present invention becomes remarkable.

That is, the ground portion indicated by the diagonal lines in FIG. 6 is
The number is larger than that of the thin film magnetic head shown in FIG.
Therefore, if the diagonally shaded portion is polished by cylindrical polishing as in the conventional case, a considerable processing time is required. Therefore, if the diagonally shaded portion is roughly cut with an arc-shaped grindstone, the machining speed is high, and therefore grinding can be performed in a short time.

In the above-described embodiment, the case where the position of the apex of the circular arc shape of the medium sliding surface and the position of the magnetic gap g are the same is illustrated. However, when these positions are deviated, FIG. A grindstone having a shape shown in (b) may be used. Further, as shown in FIGS. 5 (c) and 5 (d), the same effect can be obtained by using a grindstone in which the cutting edge portion 11 is formed in an arc shape and is linearly approximated to the arc shape in FIGS. 5 (a) and 5 (b). Has the effect of.

In order to provide a difference in the groove depth of the air grooves 9 provided on both sides of the magnetic gap g, the blades 12 provided on the grindstone 10 are made different in length.

[0033]

As is clear from the above description, according to the method of the present invention, before the cylindrical polishing process for ensuring the contact with the medium and the predetermined gap depth, the medium sliding surface is Since the air groove is formed on the surface to be formed and the surface to be the medium sliding surface is ground in an arc shape, the polishing margin in the subsequent cylindrical polishing processing is reduced, and the cylindrical polishing with a slow processing speed can be processed in a short time. can do. Further, by simultaneously performing the air groove processing and the roughing processing, the processing time can be shortened, and combined with the shortening of the cylindrical polishing time, the cost can be realized by the significant time reduction.

[Brief description of drawings]

FIG. 1 is a perspective view showing a step of forming a thin film magnetic head element, sequentially showing steps of manufacturing a thin film magnetic head by the method of the present invention.

FIG. 2 is a perspective view showing a step of manufacturing a thin film magnetic head according to the method of the present invention, sequentially showing a step of adhering a protective substrate.

3A to 3C sequentially show steps of manufacturing a thin film magnetic head by the method of the present invention, where FIG. 3A is a perspective view showing an adhering step, FIG. 3B is a perspective view showing an adhering state, and FIG. FIG. 3D is a perspective view showing a step, and FIG. 3D is a perspective view showing a cylindrical polishing step.

FIG. 4 is a perspective view of a grindstone used in the method of the present invention.

FIG. 5 is an enlarged front view of a cutting edge portion of various grindstones used in the method of the present invention.

FIG. 6 is a front view showing a change in grinding stroke due to a difference in head shape.

7A to 7C sequentially show steps of manufacturing a thin film magnetic head by a conventional method, and FIG. 7A is a perspective view showing an adhering step;
(B) is a perspective view showing a bonded state, (c) is a perspective view showing a cylindrical polishing step, and (d) is a perspective view showing a grooving step.

FIG. 8 is a perspective view showing a state of cylindrical polishing.

[Explanation of symbols]

 1 Wafer 2 Thin Film Magnetic Head Element 3 Head Element Block 4 Protective Substrate 8 Surface That Becomes Sliding Medium 9 Air Groove 10 Grindstone

Claims (1)

[Claims] 1. A step of forming a plurality of thin film magnetic head elements on a wafer, a step of cutting the wafer to cut out strip-shaped head element blocks, and a step of forming thin film magnetic head elements on the head element blocks. The step of adhering the protective substrate to the step of forming a groove parallel to the magnetic gap on the surface of the head element block to which the protective substrate is adhered, which is to be the medium sliding surface, and at the same time, the surface to be the medium sliding surface is arcuate. And a step of cylindrically polishing the surface to be the medium sliding surface so as to have a predetermined curvature so as to have a predetermined gap depth.