JPS63140414A - Marker for working gap depth in thin film magnetic head - Google Patents

Abstract

PURPOSE:To work a gap depth with high accuracy by providing another projected part at the thin film magnetic head in which a gap depth zero position is specified by the recessed part formed by an etching processing at a lower part magnetic body. CONSTITUTION:The dry etching working is simultaneously performed for a recessed part 30 and a marker 40 to house a coil conductor 24 on a lower part magnetic body 22, an insulating layer 28 is film-formed at the recessed part 30 and on the way, the coil conductor 24 is formed. For recessed parts 40a-40d of the marker 40, a length-wise direction is arranged in the grinding direction and a tip part is dislocated for a prescribed distance in the length-wise direction and arranged. Consequently, respective recessed parts 40a-40d appear successively as the grinding is proceeded, and the gap depth each time can be known. thus, even when the etching is proceeded and the gap depth zero position is dislocated, the position of the marker is also simultaneously dislocated, and therefore, the change does not occur at the relative position, and the gap depth can be worked with a high accuracy regardless of the proceeding condition of the etching.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a gap depth machining marker for accurately machining the gap depth in a UGL magnetic head.

[Conventional technology]

FIG. 2 shows an example of the manufacturing process of a slider for a magnetic disk device equipped with a thin-film magnetic head. This is a method in which a plurality of head elements are formed on one substrate and then cut into individual sliders, and consists of the following steps.

(2) A film portion 12 in which a plurality of head elements are arranged is formed by photolithography on the substrate 10 constituting the slider body.

■ Cut the substrate 10 into rows and grind them.

■ Machining the groove 14 for each row to regulate the width of the slide rail 16 6 ■ Polishing the slide rail 16 and machining the taper 18 .

(2) Cut into individual pieces to complete individual sliders 19 equipped with thin-film magnetic heads.

In the slider 19 thus completed, the magnetic head is constructed at the rear end of the slide rail 16, as indicated by the reference numeral 2"0 in FIG.

As shown in an enlarged view in FIG. 4, this thin film magnetic head 20 is constructed by forming a coil conductor 24 on a lower magnetic body 22, and forming a sector-shaped upper magnetic body 26 thereon.

FIG. 5 shows an enlarged view taken along the line A--A in FIG. 4.

This thin film magnetic head 20 has a recess 30 in the lower magnetic body 22.
The upper magnetic body 26 is flattened by forming the upper magnetic body 26 and accommodating the coil conductor 24 therein. By flattening the upper magnetic body 26, it is possible to prevent unnecessary stress from being generated and the magnetic domain from being finely divided, and the magnetic resistance can be reduced.

This thin film magnetic head 20 is manufactured by the following steps.

■ Lower magnetic material 22 is deposited on the substrate 10 by sputtering, etc.
Deposit a film.

(2) A recess 30 for accommodating the coil conductor 24 is formed in the lower magnetic body 22 by dry etching.

(2) An insulating layer 28 is formed in the recess 30. A coil conductor 24 is formed in the middle.

■ Filling the recess 30 with the insulating layer 28 and forming a flattened upper gap forming layer 31, and then depositing the upper magnetic material 2 on top of it.
6 is formed into a film. The upper magnetic body 26 and the lower magnetic body 22 are connected to each other at a coupling portion 32 to form a U-shaped core through a gap q.

The gap depth d in this a9ff2 magnetic head 20 is determined from the slider air bearing surface 33 to the gap depth position (falling start position 30a of the recess 30 in the lower magnetic body 22).
), and has good electromagnetic conversion characteristics (
q, it is necessary to precisely process the gap depth d to a minute value of several μm or less. This gap depth d is processed in the slide rail polishing process shown in FIG. 1, but it is difficult to accurately process the gap depth d in this polishing. Therefore, it has been conventionally considered to provide a processing marker.

A conventional machining marker is shown in FIG. This marker 34 is formed by forming a plurality of linear convex portions 34a on the substrate 10 or on any layer thereon, made of a fully bent, non-metallic, organic, etc.
-34e are formed. Each convex portion 34a to 34e
have the same length, and are arranged with the longitudinal direction shifted by a predetermined distance in the polishing direction. Therefore, as the polishing progresses, each of the convex portions 34a to 34e appears and disappears in sequence, so that the gap depth at that time can be known.

Now, assuming that the prescribed gap depth d in FIG. 6 is the length shown in the same figure, if the polishing is stopped at the timing when the convex portion 34d disappears, the prescribed gap depth d will be realized.

[Problem that the invention seeks to solve]

In the conventional method, it is essential that the relative position between the gap depth zero position and the marker 34 is constant, but the gap depth zero position is determined by the recess 30 in the lower magnetic body 22, as shown in FIG. The relative position with respect to the marker 34 is not constant because it changes depending on the progress of the dry etching process and is unstable. Therefore, if one line of dry etching is performed, as shown in Fig. 6, even if polished to the same position, the gap depth will be smaller than d' and the specified value d, and the gap depth will not be constant. First, the electromagnetic conversion characteristics are unstable.

This invention solves the drawbacks in the conventional techniques, and
It is an object of the present invention to provide a gap depth machining marker that can process the gap depth with high precision.

[Means for solving problems]

The marker for gap depth processing of the present invention is a thin film magnetic head in which a zero gap depth position is defined by a recess formed by etching in the lower magnetic layer, and the marker for gap depth processing can be etched into any part of the lower magnetic layer at the same time as the four parts. It consists of another recess formed by machining.

[For production]

According to the marker of this invention, since the recess defining the gap depth zero position is formed at the same time, even if etching progresses and the gap depth zero position shifts, the mark position also shifts at the same time, changing to a relative position. There isn't.

Therefore, regardless of the progress of etching, it is possible to process the burr with high precision.

[Implementation row]

An embodiment of this invention is shown in FIGS. 1 and 8.

FIG. 8 shows an example of a process for manufacturing a slider using the marker of the present invention.

(2) A film portion 12 in which a plurality of head elements are arranged is formed by photolithography on the substrate 10 constituting the slider body. At this time, markers 40 are formed on both left and right sides of the lower magnetic body for each row.

■ Cut the substrate 10 into rows and grind them.

■ Machining 14 for each row to regulate the width of the slide rail 16.

■ Slide rail 1 while looking at the markers 40 on both the left and right sides.
In addition to polishing step 6, the floating taper is processed.

(2) Cut into individual pieces to complete individual sliders 19 equipped with thin-film magnetic heads.

Thin-film magnetic head 20 and marker 4 before polishing in (2) above
An enlarged view of 0 is shown in FIG.

In this thin film magnetic head 20, a recess 30 for accommodating the coil conductor 24 is formed in the lower magnetic body 22, and the upper magnetic body 26 is flattened. By flattening the upper magnetic body 26, it is possible to prevent unnecessary stress from being generated and the ligament to be finely divided, and it is possible to reduce magnetic resistance.

This thin film magnetic head 20 is manufactured by the following steps.

■ Lower magnetic material 22 is deposited on the substrate 10 by sputtering, etc.
Deposit a film.

(2) The recess 30 for accommodating the coil conductor 24 and the marker 4o in the lower magnetic body 22 are simultaneously dry-etched.

(2) An absolutely R layer 28 is formed on the fourth part 30. A coil conductor 24 is formed in the middle.

■ After filling the recess 30 with the insulating layer 28 and flattening it,
! A V-tube forming layer 31 is formed, and an upper magnetic material 26 is further formed thereon. The upper magnetic body 26 and the lower magnetic body 22 are connected to each other at a coupling portion 32 and form a U-shaped core with a gap Q interposed therebetween.

The marker 40 has recesses 40a to 40d formed in the lower magnetic body 22 by dry etching as described above. The longitudinal direction of each of the recesses 40a to 40d is arranged in the polishing direction, and the distal ends are arranged at intervals of a predetermined distance in the longitudinal direction.

Therefore, as the polishing progresses, the recesses 40a to 40d appear one after another (as seen from the polishing surface), and the gap depth at each time can be known. Now, if the specified gap depth in Figure 1 is the length shown by d in the figure, then the four parts 4
If polishing is stopped at the timing when 0c begins to appear, the specified gap depth d can be achieved.

Furthermore, as the dry etching progresses, the position of the coil accommodating recess 30 of the lower magnetic body 22 changes, as shown by the two-dot chain line in FIG.
~710d also moves in the same direction, so there is no change in relative position. Therefore, the specified gap depth d can be achieved by polishing until the position where the recess 40G begins to appear as before.

In the example shown in FIG. 1, although the marker 40 is not covered with the gap forming layer 31, the appearance of the marker 40,
If the disappearance is viewed from the polished surface, there is no need for the marker 40 to be visible from the front, so there is no problem even if the marker 40 is covered with the burr X/tube forming layer 31.

〔Effect of the invention〕

As explained above, according to the present invention, the marker is formed at the same time as the recess defining the gap depth opening position, so even if etching progresses and the gap depth zero position shifts, the position of the mano j will also change at the same time. Because they shift, there is no change in relative position.

Therefore, the gap depth can be processed with high precision regardless of the progress of etching.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing an embodiment of the present invention. FIG. 2 is a diagram showing an example of a slider manufacturing process. FIG. 3 is an enlarged view of the slider. FIG. 4 is an enlarged view of the thin film magnetic head. FIG. 5 is a view taken along the arrow 8- in FIG. 4. FIG. 6 is a diagram showing a conventional processing marker. FIG. 7 is a partially enlarged sectional view of the thin film magnetic head. FIG. 8 is a diagram showing an example of a process for manufacturing a slider using the marker of the present invention. 20... Thin film magnetic head, 22... Lower magnetic body, 3
0... recess, 40... marker, 40a to 40d...
・Concavity. Applicant: Nippon Musical Instruments Manufacturing Co., Ltd.; 4.0. 4Q Figure 8

Claims (1)

[Claims] In a thin film magnetic head in which a gap depth zero position is defined by a recess formed by etching in the lower magnetic layer, another recess formed by etching at the same time as the recess is formed in any part of the lower magnetic layer. A marker for gap depth processing in thin film magnetic heads.