JPS60226007A - Thin film magnetic head - Google Patents

Abstract

PURPOSE:To prevent a contour effect by the linear change in the film thickness of a lower or upper magnetic layer in the transverse direction of tracks. CONSTITUTION:A film consisting of SiO2 or Al2O3 is formed as a non-magnetic layer 2 on a substrate 1 and is worked with a hole tapered at angle alpha1. The hole for embedding a lower core is made into such shape of which one side on the side for forming a front gap has an angle B to a cylindrical grinding surface C-C'. A magnetic material consisting of Fe-Al-Si, Ni-Fe, amorphous material or the like is then formed as a film thereon and is flattened by lapping. SiO2 or Al2O3 is thereafter formed to the prescribed thickness to control the gap and further the film consisting of Al or Cu is formed thereon and is etched to manufacture the coil 8. A film consisting of SiO or SiO2 is formed thereon and the part for the front and back gaps is etched away. An insulating layer 9 is formed thereon and the film of the magnetic material is again formed and is patterned at a taper angle d2 and thereafter the magnetic material is ground off by cylindrical grinding down to the line C-C'. The edges of the upper and lower cores are thus made non-parallel with the gap line and the reproduction with high fidelity is made possible.

Description

[Detailed description of the invention] [Field of application of the invention] The present invention relates to a thin film magnetic head.

[Background of the invention]

A conventional thin film head is one in which a magnetic gap of about 2 to 20 μm is formed on the substrate surface, a nonmagnetic film is interposed as a gap material on top of the thin film, and a magnetic film is further deposited on top of that to form the magnetic gap of the spatula P. was the majority.

The track width of the head is obtained by cutting the magnetic film into pieces using techniques such as etching or machining. In this case, the shape of the magnetic core near the gap of the head is parallel to the gap, and there are edges of the core on the left and right sides of the gap, so a so-called contour effect occurs that picks up signals on Chi and Zo, even at these edge parts, and faithful This was a problem when reproducing signals. Originally, the contour effect is a phenomenon in which signals recorded on the magnetic recording medium are magnetically coupled to the edges of the core other than the gap of the magnetic head and passed through the head winding, resulting in a temporal shift from the read signal of the gap. It is used to read signals, and it is well known that in this case too, there is an effect of so-called azimuth loss of the head. By using the effect of
^-φ1 [Object of the Invention] An object of the present invention is to provide a thin-film magnetic head that does not cause contour effects.

[Summary of the invention]

The present invention provides a thin film magnetic head in which a lower magnetic layer is buried in the surface of a nonmagnetic layer formed on a nonmagnetic substrate, and an insulating layer, a coil conductor layer, and an upper magnetic layer are sequentially laminated on the lower magnetic layer. A thin film magnetic head characterized in that the thickness of at least one of the lower magnetic layer and the upper magnetic layer varies linearly in the track width direction.

This can prevent contour effects.

[Embodiments of the invention]

An embodiment of the present invention will be described below based on the drawings. In this example, a lower magnetic layer 3 is buried in the surface of a non-magnetic layer 2 formed on a non-magnetic substrate 1, and an insulating layer 4, a coil conductor layer 8, and an upper magnetic layer 5 are formed on the lower magnetic layer 3. In a thin film magnetic head formed by sequentially laminating layers, the thickness of at least one of the lower magnetic layer 3 and the upper magnetic layer 5 varies linearly in the track width direction.

This prevents contour effects.

Hereinafter, more specific details of an embodiment of the present invention will be explained using the drawings.

Figure 1 is a view from the head sliding surface of a thin-film magnetic head.
FIG. 2 is a cross-sectional view of FIG. 1 in the magnetic path length direction. 1 is a nonmagnetic substrate, 2 is a nonmagnetic layer, 3 is a lower magnetic layer that becomes a lower core embedded in the hole of the nonmagnetic thin layer 2, 4 is an insulating layer that defines the head gap, and 5 is an upper core. Upper magnetic layer, 8 is a one-turn signal coil conductor layer, 9 is an insulating layer for insulating the signal coil and filling the steps, 6 is an adhesive layer, 7 is an adhesive layer 6
It is a protective plate glued with

A specific manufacturing method will be described below. First, a method for making the gap forming surface and the edge portions of the upper and lower thin film cores non-parallel to the Gyazzo line will be explained with reference to FIGS. 3 and 4.

FIG. 3 is a perspective view for explaining the method, and a cross section taken along the line pp' of FIG.

In FIG. 3, there are two 9 thin film layers 12, 1 on a substrate 11.
No. 3 is formed so that its boundary surface overlaps with the substrate surface at an angle α. In addition, two thin film layers 12 and 13
The surface of is parallel to the substrate surface.

The two thin film layers 12 and 13 formed in this way are drawn at their overlapping portions by a straight line P that makes an angle β with the straight line AA' formed by the interface between the thin film layers 12 and 13 in contact with the substrate surface.
When cut at P', a cross section as shown in FIG. 4 is obtained.

As is clear from FIG. 4, according to the above method, the straight line RR' formed by the edge of the interface between the thin film layers 12 and 13 is
Straight line PP' created by the edges of the substrate surface and thin film layer surface
, QQ' are non-parallel.

Using this method, the thin film head of the embodiment shown in FIGS. 1 and 2 is manufactured. That is, the cut along the PP' line in FIG. 3 corresponds to the cylindrical grinding surface, and the thin film layer 12
, 13 correspond to the nonmagnetic layer 2 and the lower core 3 in FIG. 1, respectively, and if the surfaces of the thin film layers 12 and 13 are the gap forming surfaces, then the straight line RR' in FIG.
TantaR's L Yohi! ;Q l;→−−star −(4
−τ☆π −ma n) Hits the spot. Furthermore, if the thin film layer 12 in FIGS. 3 and 4 is the upper core 5, and the substrate surface is the gap forming surface, then the straight line RR' in FIG. (However, in this case, it is assumed that there is no thin film layer 13).

Next, a more specific manufacturing method will be explained with reference to FIGS. 5 and 6. FIG. 5 is a process diagram for explaining the method of forming the lower core, and FIG. 6 is a front view (however, the upper core 5 and the insulating layer 9 are omitted) and a cross-sectional view of the head element after the wafer processing is completed. The symbols are the same in FIG. 1 and FIG. 2. The process will be explained below.

1) SiO2, At, or O as the nonmagnetic layer 2 on the substrate 1.

A film is formed by s/IP ivy, vapor deposition, etc., and a hole is formed with a chi/IP angle αl as shown in FIG. 5(a).

Processing methods include a mask with a cheek (for example, a method in which the resist/base turn edge is sloped by selecting post-bake conditions, a method in which the resist is isotropically etched using glazma etching and a method in which the JP turn edge is sloped). There are two methods: etching using ion etching (e.g.), or etching by tilting the substrate using ion etching.

Alternatively, the nonmagnetic layer 2 may be formed by a lift-off method to form a hole for embedding the lower core. Chi/4' angle is 20' ~
Around 60° is ideal.

The shape of the hole for embedding the lower core mentioned above is shown in Figures 3 and 4.
As is clear from the explanation of the figure, as shown in FIG. 6(a), one side on the front gap forming side is the cylindrical grinding surface c-
It is made to form an angle β with c' (parallel to the coil noreen end) (the back gap side may be parallel).

2) Next, a film of magnetic material such as Fe-At-St, Ni-Fe, amorphous, etc.
As shown in b), flatten by lapping.

3) 5to2. ALzOa or the like is formed by sputtering to a predetermined thickness that defines the gap.

4) After forming a film of At, Cu, etc. by sputtering, vapor deposition, etc., etching is performed as shown in FIG. 6(a) to form the coil 8.

5) Add 810, 5i02, etc. on top of this,
A film is formed by vapor deposition or the like, and the front and back gap portions are removed by etching to form an insulating layer 9.

6) Again Fe-AL-St, Ni-FL,
1)
By the etching method described above, the taper angle α2 is cut and turned as shown in FIG. 6(b). Similar to the lower core mentioned earlier, this shape also has a cylindrical grinding surface C-
Create a shape that forms an angle between C' and β.

7) After completing the wafer processing in this way, the 6th
As shown in the figure, by cylindrical grinding down to line cc', the thin film head shown in FIGS. 1 and 2 can be obtained.

As described above, according to this example, the edges of the upper and lower cores can be made non-parallel to the gap line, and the contour effect can be solved.

Further, although this embodiment has been described with respect to a single-layer core, the same method can be applied to a core with a multilayer structure. In particular, for the lower core, two squares (
After turning the insulating layer of +; Thereafter, it is flattened by a technique such as lapping to form a gap surface.

With this configuration, the core interlayer plane that becomes the pseudo magnetic gap has an azimuth angle with respect to the true magnetic gap plane, so that the contour effect caused by the core interlayer plane can be reduced. On the other hand, regarding the upper core, after forming the gap material 4 on the substrate, the first layer of the upper core is formed, and the sixth layer is formed.
As shown in Figure (b), patterning is performed in a predetermined shape with the Theno 4 angle set to α2. Next, the core interlayer material and the second and subsequent layers of the upper core are sequentially laminated, and finally the upper multilayer core is stripped all at once. By this method, the Theno generating angle α2 of the upper core of the first layer is transferred to the upper core and glabella material of the second and higher layers, so that the interlayer plane of the upper core, which becomes a pseudo magnetic gap, becomes a true Since it has an azimuth angle with respect to the magnetic gap plane, the contour effect can be reduced. By adopting the above-mentioned structure of the multilayer structure core, it is possible to realize a thin film magnetic head with less eddy current loss (improved high frequency characteristics) and reduced contour effect compared to a single layer structure core.

〔Effect of the invention〕

As described above, according to the present invention, the contour effect can be solved.

It became possible to create a magnetic head capable of high-fidelity playback.

[Brief explanation of the drawing]

1 and 2 show a thin film magnetic head according to an embodiment of the present invention, FIG. 1 is a front view from the sliding surface, and FIG.
The figure is a sectional view. FIG. 3 is a perspective view of essential parts for explaining an embodiment of the present invention, FIG. 4 is a sectional view taken along the line P-P' in FIG. 3, and FIG. 5 is a thin film magnetic field according to an embodiment of the present invention. FIG. 6 is a process diagram for explaining the method for forming the lower core of the head. FIG. 6 is a diagram showing the state of a thin film magnetic head according to an embodiment of the present invention after the wafer etching process is completed, and FIG. 6(a) is a front view thereof. FIG. 3B is a sectional view thereof. 1.11...Substrate, 2...Nonmagnetic layer, 3...Lower magnetic layer (lower core), 4...Insulating layer that defines the gap, 5...Upper magnetic layer (upper core) , 12 , 1
3... Thin film layer. Figure 1 Figure 2 Figure 3 V\ Figure 4 Figure 5 Figure 6

Claims (1)

[Claims] 1. A lower magnetic layer is buried in the surface of a nonmagnetic layer formed on a nonmagnetic substrate, and an insulating layer, a coil conductor layer, and an upper magnetic layer are sequentially laminated on the lower magnetic layer. 1. A thin film magnetic head characterized in that the thickness of at least one of the lower magnetic layer and the upper magnetic layer varies linearly in the track width direction. 2. The thin film according to claim 1, wherein the lower magnetic layer is a multilayer film having a nonmagnetic insulating layer therebetween, and the nonmagnetic insulating layer is non-parallel to the insulating layer in the track width direction. magnetic head.