JPH0218707A - Manufacture of thin film magnetic head - Google Patents

Abstract

PURPOSE:To cause the value of a gap length to be constant and to attain manufacture with satisfactory reproductivity by measuring the thickness of a gap layer before filming an upper magnetic substance layer and executing the filming with overlapping a gap control layer, which has thickness to correspond to a measured value, on the gap layer. CONSTITUTION:A lower magnetic substance layer 2, which is composed of a magnetic substance, is formed on a substrate 1 and next, a gap layer 3 to be composed of an insulator is successively filmed and formed. Here, a lowest layer 5a of an insulator layer 5 to surround a coil 4 is filmed and a first conductor layer 4a of the coil 4 is filmed. Further, a second insulator layer 5b, a second conductor layer 4b and a third insulator layer 5c are successively filmed and formed. The thickness of this gap layer 3 is measured and difference between this measured value and target gap thickness is calculated. Then, the filming is executed so as to be the same thickness as the target gap thickness and a gap control layer 6 is obtained. Next, an upper magnetic substance layer 7 is filmed and formed on this gap control layer 6 and a prescribed protecting layer is formed on the layer 7. After that, the substrate 1 is cut in a prescribed position and a cutting surface is ground. Then, a gap surface to slide and contact to a magnetic medium is formed. Then, the magnetic head of high recording and reproducing function can be stably manufactured.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method of manufacturing a thin film magnetic head for exchanging signals with a magnetic storage medium in a magnetic disk device or the like.

``Prior art'' Thin-film magnetic heads are smaller than conventional magnetic heads using bulk cores, making it possible to reduce the track width and recording in high frequency bands. In either case, high-density recording is possible.Therefore, it is used to take advantage of this advantage in floating magnetic heads of magnetic disk drives.

An example of the structure is shown in FIG. 3, in which a lower magnetic layer 2 is formed on a non-magnetic substrate 1, and a gap layer 3 is interposed between the lower magnetic layer 2 and a conductive layer constituting the coil 4. A double film is formed, and this is surrounded by an insulating layer 5, and then an upper magnetic layer 7 is formed. The coil 4 is located concentrically around a back gap (not shown) between the lower magnetic body R2 and the upper magnetic layer 7, and is located concentrically around the back gap (not shown) between the lower magnetic body M2 and the upper magnetic layer 7. The above-mentioned gap layer sandwiched between the magnets 8 constitutes the magnetic gap 8.

As is well known, there are two methods for forming such a pattern: one is to first form a film on the entire surface by sputtering or vapor deposition, and then remove unnecessary parts, and the other is to mask the unnecessary parts in advance and then form a film only on the necessary parts, such as by plating. There is a method of coating.

After the film forming process as described above is completed, cutting and polishing are performed to expose the magnetic gap 8.

[Problems to be Solved by the Invention] By the way, in the magnetic head as described above, setting the gap length, that is, the thickness of the gap layer 3 to an appropriate value corresponding to the frequency, improves the recording density and accuracy. becomes important. Therefore, when forming the gap layer 3, the patterning of the gap layer 3 is managed to fall within a certain range by strictly controlling the film forming conditions such as sputtering, vapor deposition, or plating. However, as mentioned above, after forming the gap layer 3, there is a step of forming the coil 4 and the insulating layer 5 while forming the two-part magnetic layer 7. Exposure to etching, masking, sputtering, and vapor deposition. Therefore, the thickness of the gap layer 3 may vary entirely or partially, and as a result, the accuracy of the thickness decreases, and as a result, the gap length does not reach a predetermined value and the magnetic characteristics of the head deteriorate.

SUMMARY OF THE INVENTION An object of the present invention is to provide a method for manufacturing a thin film magnetic head that can manufacture a thin film magnetic head with good reproducibility while maintaining a constant gap length value.

[Means for Solving the Problems] In order to solve the above-mentioned problems, the present invention measures the thickness of the gap layer before forming the upper magnetic layer, and displays the measured value on the gap layer. The thickness of the gap layer can be made accurate by depositing gap adjustment layers with thicknesses corresponding to the thickness of the gap layer. As a method for measuring the thickness, it is preferable to employ a non-contact film thickness meter based on the principle of spectral reflection interferometry or the like.

[Function] In the manufacturing method of such a thin film magnetic head, after forming the gear layer, the thickness of the gap layer is reduced in the process of forming the coil layer and the insulator layer. Fine adjustments to the thickness can be made by measuring the thickness of the gap layer at the same time as the film is being deposited, and then depositing a new film to a thickness that is less than the desired thickness according to the measured value. .

[Embodiment j] Hereinafter, the present invention will be described in detail with reference to the drawings in FIGS.

In FIG. 1(A), a lower magnetic layer 2 made of a magnetic material is formed on the second part of the substrate 1, and then a gear and a knob layer 3 made of an insulating material are formed.
This figure shows a state in which the films are sequentially formed.

Here, the lowermost layer 5a of the insulating layer 5 surrounding the coil 4 is formed (FIG. 2 (B)), the first conductor layer 4a of the coil 4 is formed (FIG. 3 (C)), and then the second insulating layer 5 is formed (FIG. Body layer 5b (same figure (
d)), the second conductor layer 4b (FIG. 4(E)), and the third insulating layer 5c (FIG. 1(F)) are sequentially formed. These steps are performed by alternately performing film forming steps such as sputtering and vapor deposition, and pattern forming steps such as etching and masking.

In the present invention, the thickness of the gap layer 3 is measured here using a non-contact film thickness meter based on the principle of spectral reflection interferometry or the like. and,
The difference between this measured value and the target gap thickness is calculated, and the film is deposited to the same thickness (see figure (G)).
, gap adjustment layer 6. This gap adjustment layer 6 naturally covers the insulator layer 5 surrounding the coil 4. Next, the upper magnetic layer 7 is formed on -F of the gap adjustment layer 6 (FIG. 1(D)), and a prescribed protective film (as shown in the figure) is formed thereon, and then the substrate 1 is It is cut at a predetermined position and the cut surface is polished to form a gap surface (the path shown in the figure) that slides into contact with the magnetic medium.

FIG. 2 shows another embodiment of the present invention, in which the insulator layer 5 is etched excessively and the conductor layer 1b of the coil 4 protrudes from the insulator layer 5.

In such a case, if there is no gap adjustment layer 6, the upper magnetic layer 7 and the coil 4 will come into direct contact and short circuit, but in the case of the present invention, the gap adjustment layer 6 is an electrically insulating layer. Since it acts as a catalyst, it can be used as a product, and the yield can be improved.

``Effects of the Invention'' As described in detail above, the present invention provides a cap layer made of a non-magnetic material, a coil layer made of a conductor, an insulating layer made of an insulator, and a top magnetic material layer. In a method for manufacturing a thin film magnetic head in which layers are sequentially formed,
By measuring the thickness of the gap layer before forming the above-mentioned upper magnetic layer, and forming a gap adjustment layer with a thickness according to the measured value on top of the gap layer, each The gap thickness can be set strictly and accurately, thereby creating a stable magnetic head with high recording and playback functions. This has an excellent effect of allowing the production of this product.

[Brief explanation of the drawing]

Figures 1 (a) to 3) are cross-sectional views showing the steps of one embodiment of the present invention, Figure 2 is a cross-sectional view showing another embodiment of the present invention, and Figure 3 is a cross-sectional view showing a conventional example. It is. 2... Lower magnetic layer, 3... Gap layer, 4... Coil, 5... Insulator layer, 6
... Gap adjustment layer, 7 ... Upper magnetic layer.

Claims (1)

[Claims] In a method for manufacturing a thin film magnetic head in which a gap layer made of a non-magnetic material, a coil layer made of a conductor, an insulating layer made of an insulator, and an upper magnetic layer are sequentially formed on a lower magnetic layer, the above A thin film magnetic head characterized in that the thickness of the gap layer is measured before forming the upper magnetic layer, and a gap adjustment layer having a thickness according to the measured value is layered and formed on the gap layer. manufacturing method.