JPS58128014A - Thin film magnetic head element - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a thin film magnetic head cable, and more particularly, a unit magnetic head group consisting of a ferromagnetic thin film, a conductive thin film, and an insulating thin film is formed on a substrate, The present invention relates to an improvement in a means for detecting the amount of polishing of a thin film magnetic herad element body, which is provided with means for detecting the amount of polishing on the left and right sides of the array direction.

FIG. 1 is a top view showing a conventional example of this type of thin film magnetic head element. In FIG. 1, 1 is a substrate, 2 and 5 are conductive layers forming coils of a unit magnetic head group formed on the substrate 1, and magnetic layers forming magnetic cores, 4.5 are left and right sides of the substrate 1, respectively; That is, these are detection marks provided on the left and right sides of the unit magnetic head group in the arrangement direction to detect the amount of polishing.

For detection! -4.5, as shown in the figure, one side of the two orthogonal sides is parallel to the gap depth direction of the magnetic head and is opposite to each other, and the intersection of that side and the opposite side at right angles A right-angled isosceles triangle is arranged so that the angle is on the line A-A' connecting the lower end of the magnetic head gap. Therefore, for example, when the head has been polished up to line B-B', by observing the width of the gaps and gaps of the detection marks 4 and 5, it is possible to know the parallelism of the head polishing and the gap depth. . In other words, in the case of Shiroku 4, it can be seen that the B-8' line is parallel to the A-A' line, and the '
The void depth can be determined from the value of .

However, in the conventional example configured in this way, in order to obtain the desired gap depth, K is used for head polishing and detection on the head polished surface! - To the width of 4 and 5.

The drawback is that the observations of the crows have to be repeated many times, which requires a great deal of time and effort. Also, connect the upper end of the group 1/R1 to the lower end of the void @A-
The amount of polishing up to A' is usually several hundred microns, and the detection marks 4 and 5 are right-angled isosceles triangles, so they need to have the same length in the width direction of the substrate 1, and the substrate 1 has no other than the magnetic head group. In addition, the detection marks 4 and 5 must be made larger, which creates a time-consuming process that hinders integration during the manufacture of the magnetic head element.

The present invention has been made in view of the above, and its purpose is to be able to perform head polishing more effectively,
Moreover, it is an object of the present invention to provide a thin-film magnetic head element that can be manufactured without interfering with integration during manufacturing of the head element.

A feature of the present invention is that the means for detecting the amount of polishing when polishing is performed to set the depth of the gaps provided on the left and right sides of the unit magnetic head group on the substrate to a predetermined value in the arrangement direction, At least one triangular or square detection mark provided so as to be in the same direction, Kv & girder identification marks on the left and right sides of this detection mark for identifying the polishing position of this detection mark during polishing, and Kv & girder identification marks on the left and right sides of this detection mark to identify the polishing position of this detection mark during polishing. It consists of a detection electrode for electrically detecting the fact that it has been polished.

The present invention will be explained in detail below using the embodiments shown in FIGS. 2 to 6.

FIG. 2 is a top view showing one embodiment of the thin film magnetic head element of the present invention, FIG. 3 is a sectional view taken along line c'-c'' in FIG.
The figure is a sectional view taken along the line DD' in FIG. 2, and the same parts as in FIG. 1 are designated by the same reference numerals. In FIG. 2, a substrate 1 made of insulating ferrite, ceramic or glass material is shown.
A conductive magnetic material 6 made of permalloy or sendust is formed in a predetermined shape on top of the conductive magnetic material 6, and then an insulating layer made of silicon dioxide (Sin, ) or alumina (<1ttos), etc., which becomes a magnetic gap, is formed on the coil. The conductive layer 2, the detection mark 7.8, and the identification mark 7α for identifying the polishing position of the detection mark 7.8.

7b, 8α, Bb and detection electrodes 9 and 10 for detecting the end of polishing are made of aluminum (,4t), copper (Cμ), gold (
It is formed as shown in the figure using a conductive material such as JI&), and an insulating layer made of organic or inorganic material.

By forming the upper magnetic layer 3 serving as a magnetic core into a predetermined shape, a thin film magnetic head element is obtained.

In the initial stage of head polishing, the dimensions of the detection marks 7 and 8 in the width direction are observed to determine the parallelism with the head arrangement direction. As shown in the figure, the detection mark 7°8 is a right-angled isosceles triangle whose long side is perpendicular to the head arrangement direction, that is, in the polishing direction, and whose diagonal angle is 90 degrees. The upper region of the 90-degree vertex is identified using identification marks 7b and Bb, and the lower region is identified using identification marks 7α and 8α.

In the initial polishing, when the polishing is performed to the c,'-c' plane, when observed from the polished surface, the C-(,' cross section becomes K as shown in Fig. 3. In other words, the outside of the detection mark 7.8 Since the identification marks 7b and Bb are visible, respectively, it is possible to identify that the polished surface is located in the area above the detection mark 7.8. The distance from the plane E-E' is determined by the detection mark 7.
If t is the distance between the apex of the 90 degree angle of 8 and the E-E' plane, and A is the height of the right isosceles triangle (the accuracy of t and A is determined by the accuracy of butterflying), then From the geometrical relationship, the position of the detection mark 7 is (10^-4), and the position of the detection mark 8 is (10-'4), while parallel to the E-E' plane of the polished surface. The deviation from the ((”a'
4).

From this, in order to obtain parallelism, K should be corrected so that (ds-d4) becomes zero.

In the initial polishing, even if the polishing is carried out to the DD' plane, K, identification marks 7α, 8α as shown in FIG.
are visible in the detection marks 7 and 8, respectively, so similarly to the above, the distance between the polished surface and the E-E' plane becomes (t'' 10tts) at the position of the detection mark 7, and the detection mark 8 It becomes ('4+'s) at the position of , and it can be seen that the deviation of the polished surface from the plane parallel to the E-E' plane is represented by <=ts-tie>.

Next, in the initial polishing, from the time when the polished surface becomes parallel to the E-E' plane, the polishing is continued without observing the detection mark 7.8. This is because it is known that in normal polishing, once parallelism is achieved, there is almost no deviation in parallelism as the polishing continues. When the polished surface reaches the desired E-E' circle, the electric loop between the polishing completion detection electrodes 9 and 10 is disconnected, so if polishing is continued until then, the polished surface E- has the desired void depth.
E' plane is obtained. The disconnection of the electrical loop occurs at the bonding pad 9α of the electrode 9, the connecting portion 9b, the lower conductive magnetic body 6, the connecting portion 10b of the electrode 10, and the bonding pad 1.
Conductivity to 0α is achieved by polishing to the E-E' plane.
This occurs because the electrodes 9 and 10 are cut.

In the thin film magnetic head element having the above structure, the detection mark 7.8 is identified! -ri7a, 7b, f3a.

Once the parallelism is achieved using 8b, the desired E can be achieved without observing the detection mark 7.8 on the polished surface of the head.
- Polishing can be performed up to the E' surface, and the polished surface is E-E.
When the polishing surface is reached, the electrical loop made up of the electrodes 9, 10, etc. is broken, so it is possible to know when the polishing is finished.

Therefore, it is no longer necessary to repeat head polishing and observation of the detection mark width many times as in the conventional method.

Furthermore, since the detection marks 7.8 are in the form of right-angled isosceles triangles, and their long sides are arranged in the polishing direction, that is, in the direction perpendicular to the arrangement direction of the magnetic heads, when compared with FIG. The width of the detection mark 7.8 in the head arrangement direction is 1
This reduces the width wasted in providing the detection marks 7 and 8 on the substrate 1, and there is no problem with integration when manufacturing the head body.

FIG. 5 is a top view of main parts showing another embodiment of the present invention.

In FIG. 2, one right isosceles triangular detection mark 9, 1 is placed in the polishing direction on both sides of the head arrangement direction.
0, but in FIG. 5, a plurality of each (N
5) detection marks 11t12e15 are provided continuously in the polishing direction, and identification marks 114! , 11A, 12g, 12b, 15g, 1
5A and each of the detection marks 11 to 13. According to FIG. 5, the length of each detection mark 11 to 15 can be reduced to 1/3 of the detection mark 7 in FIG. 2, and the required width for the detection mark is smaller than that of the conventional one. 1/
fX115, and if the number of detection marks is N, then
It can be made as small as 1/fi×1/N.

Moreover, FIG. 6 is a top view of the main part showing still another embodiment of the present invention, and in FIG. 6, a square with one diagonal line in the polishing direction is used as the detection mark. In FIG. 6, three such detection marks 14, 15° 16 are provided consecutively as shown.

Also, the corresponding identification marks are 14α, 14b, 1
5α, 15A.

16tL, 164 and respective detection marks 14-1
It is set every 6. Even in this case, the same effect as in FIG. 5 can be obtained.

As explained above, according to the present invention, head polishing can be performed more effectively, and furthermore, it is possible to avoid hindrance to integration during manufacturing of the head body.

[Brief explanation of drawings]

FIG. 1 is a top view of a conventional thin film magnetic head element, and FIG. 2 is a top view showing an embodiment of the thin film magnetic head element of the present invention.
FIG. 3 is a sectional view taken along line c-c' in FIG. 2, FIG. 4 is a sectional view taken along line D-D' in FIG. 2, and FIGS. 5 and 6 each show other embodiments of the present invention. FIG. 3 is a top view of main parts. 1... Substrate 2... Conductive layer 3... Magnetic layer 6... Conductive magnetic material 7.8... Detection marks 7α, 77, 8α, 8b... Identification mark 9. 10
...Detection electrode O 1 Figure 3rd prisoner 4th prisoner 5th cause O b mouth

Claims (1)

[Scope of Claims] A unit magnetic head group consisting of a ferromagnetic thin film, a conductive thin film, and an insulating thin film is formed on a TI plate, and air gap depths are formed on the left and right sides of the arrangement direction of the unit magnetic head group on the substrate. In a thin film magnetic head element comprising means for detecting the amount of polishing when polishing to a predetermined value, each of the means for detecting the amount of polishing is configured such that the long side or one diagonal line is in the polishing direction. At least one triangular or square detection mark provided, identification marks provided on the left and right sides of the detection mark for identifying the polishing position of the detection mark during polishing, and that the polishing has been completed to the polishing end position during polishing. 1. A thin film magnetic head element comprising a detection electrode for electrically detecting. 2. The thin giH according to claim 1, wherein the triangle or quadrilateral is a right isosceles triangle or a square, respectively.
1ki head.