JPH0516082B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method of manufacturing a magnetic head. More specifically, the present invention provides a substrate made of ceramic ferromagnetic material or ceramic nonmagnetic material.
This invention relates to a method for manufacturing a composite magnetic head that combines a core and a ferromagnetic metal thin film.

(Prior Art) With the recent increase in the density of magnetic recording, magnetic tapes with higher residual magnetic flux densities Br are being used, and in order to cope with this, magnetic heads with high magnetic flux densities and narrow track widths are required. ing.

Conventionally, such magnetic heads were developed by
60-223012, a thin film of ferromagnetic metal is formed on a magnetic core made of ferromagnetic oxide by vacuum thin film forming technology, and the gap facing surface (hereinafter referred to as A thin film magnetic head is known in which a magnetic gap is formed between thin films of ferromagnetic metal exposed at a butt joint surface parallel to the magnetic gap.

The formation of a thin film of ferromagnetic metal, which is important in the manufacture of this magnetic head, is usually performed by a vacuum thin film forming technique such as sputtering. The metal thin film is formed by sputtering from the side wall of a groove previously provided on the substrate to the substrate surface, and then the sputtered film left on the groove wall is removed by removing the spattered film on the substrate surface by grinding with a whetstone or the like. The upper end surface is formed to form a gap.

For example, as shown in FIG.
A triangular groove 102 is bored in 01, and after filling the groove 102 with melting glass 103, a surface polishing process is performed. Then again, the V-shaped track groove 104
After forming the core block 101, a thin film 105 of ferromagnetic metal is formed on the upper surface of the core block 101 by sputtering or the like. Next, the upper surface of the core block 101 is polished to form a core half block 101B.
A similar core half block 101A having winding grooves is obtained in the same process. The two core half blocks 101A and 101B are butted against each other to form a magnetic gap g (Japanese Patent Laid-Open No. 60-205808).

(Problem to be solved by the invention) However, when forming a film by sputtering, the energy of the sputtering particles is much larger than that of vapor deposition, so the increase in adhesion to the substrate and the internal stress caused by the particle implantation effect. This causes various phenomena such as an increase in the strength of the substrate, and has a great effect on the strength of the substrate.

That is, if the orientation with respect to the target differs, the density of the thin film will differ due to differences in the probability of ion collision and slight differences in the atmosphere, and cracks will tend to occur at the boundaries. Generally, as shown in FIG. 6, a dense film 202 is formed on the gap facing surface 201 with respect to the target, and compressive stress acts on the film, while the inclined thin film forming surface 203
A low-density film 204 is formed in the film, and tensile stress acts within the film. Therefore, the gap facing surface 2
Cracks 206 occur at the boundary portion 205 between 01 and the thin film forming surface 203, which adversely affects the magnetic properties and mechanical properties. Therefore, the thin film forming surface 203
When the sputtered film 204 is formed into columnar crystals with a suitable density, the sputtered film 204 on the gap facing surface 201 becomes
02 density becomes too high, the gap facing surface 20
1, there is a high possibility that a crack 206 will occur.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a method of manufacturing a magnetic head in which cracks are less likely to occur on the surface facing the gap.

(Means for Solving the Problems) In order to achieve the above object, the magnetic head manufacturing method of the present invention provides a method for manufacturing a magnetic head in which a thin film is formed on a substrate surface that is close to or adjacent to a thin film forming surface and is opposite to the sputtering direction. A thin metal film is formed by forming an inclined surface and sputtering.

(Function) Therefore, the densest metal thin film is formed on the inclined surface near or adjacent to the thin film formation surface due to the orientation with respect to the target, and the densest metal thin film is formed on the substrate surface facing the sputtering direction. Eliminates the influence of internal stress generated in a metal thin film on the substrate near the thin film formation surface.

(Example) Hereinafter, the manufacturing process of the magnetic head of the present invention will be explained in detail based on the drawings.

First, a large number of rectangular, V-shaped, or trapezoidal track grooves 13 are formed at a predetermined pitch on the gap-facing surface 3 of the substrate 1 by grinding, and the track grooves 13 extend in a direction perpendicular to the tape sliding surface 5 (in the transverse direction). [Figure 1a].

Next, an inclined surface 2 is formed adjacent to the side wall surface/thin film forming surface 6 of the track groove 13 on the substrate surface facing the sputtering direction, which in this embodiment is on the gap facing surface 3 [FIG. 1b] . As shown in FIG. 2A, this inclined surface 2 is formed on the gap facing surface 3 by drilling a triangular groove 14 using a grinder or the like. Thereby, the thin film forming surface 6 and the inclined surface 2 make the substrate 1 have a V-shaped cross section. In this case, the track groove 13 and the triangular groove 9
It may be formed separately, but it may also be ground at once using a general grindstone or the like. In the case of the inclined surface shown in FIG. 2A, there remains a flat portion of the gap facing surface 3 where compressive stress tends to accumulate, so there is a risk that cracks 15 may occur as shown in FIG. 2C.
Since the crack 15 is propagated in the opposite direction away from the necessary portion 16 remaining in the finished product, there is no practical problem. Further, as shown in FIG. 3A, the inclined surface 2 may be large enough to connect adjacent track grooves 13. Further, as shown in FIG. 4, the curved inclined surface 2 and the thin film forming surface 6 may be provided continuously and alternately. Furthermore, Figure 5 A, B
The inclined surface 2 may be provided slightly apart from the thin film forming surface 6 as shown in FIG. In this case, the distance between the thin film forming surface 6 and the inclined surface 2 must be 10 times or less than the film thickness l to be effective, preferably 3 times or less, and most preferably as shown in FIG. It is better to set it to 0.

It is desirable that the inclination θ of the inclined surface 2 with respect to the gap facing surface 3 is in the range of 5 to 85 degrees, preferably 15 to 70 degrees, and most preferably 30 to 60 degrees. This substrate 1 is divided into two along a plane perpendicular to the above-mentioned transverse direction, that is, a plane parallel to the tape sliding surface 5, and is divided into a pair of substrates 1A and 1B.

Next, these are cleaned and a magnetic thin film 4 of ferromagnetic metal is formed to have a uniform thickness along the ridge line 7 using a vacuum thin film forming technique [FIG. 1c].
Usually, the magnetic film 4 is formed by sputtering a ferromagnetic metal such as Sendust alloy. For example, when targeting standard Sendust alloy, sputtering is performed in an argon gas atmosphere.
It is performed at a rate of about 400 Å/min at a substrate temperature of 200°C. By sputtering, the metal thin film 4 is
For example, it is formed as shown in FIG. 2B or FIG. 3B. Incidentally, the metal thin film usually has a thickness of 5% per layer.
It is preferable to form a substantial multilayer film with a thickness of ~6 μm, and it is usually formed by sputtering a ferromagnetic metal intermittently, or by sputtering a ferromagnetic metal and a nonmagnetic material alternately. Therefore, a multilayer magnetic thin film with a crystal grain size of 520 to 570 Å is formed.

Next, the track grooves 13 are filled with high melting point glass 10 to protect the thin film 4 [Glass Bonding Figure 1d].

After that, the gap facing surface 3 and the tape sliding contact surface 5 are
is ground to a flat surface with a specified surface roughness. Grinding is usually done with a lap to give a mirror finish. As a result, a track is formed by the end face of the metal thin film 4 formed on the thin film forming surface 6.

After that, the groove 13 is placed next to the track groove 13 described above.
A track regulating recess 8 is ground along the groove to eliminate false gaps [Fig. 1e]. When the recess 8 is ground, the metal thin film 4 formed on the inclined surface 2 is removed, and a track of a predetermined width is formed only by the metal thin film 4 on the thin film forming surface 6.

Thereafter, a winding groove 12 is formed on the gap facing surface 3 of one of the substrates 1A [FIG. 1f]. This winding groove 12 regulates the depth dimension. Note that the winding groove 12 is not formed on the other substrate 1B. Next, SiO ₂ is applied to the gap facing surfaces of both substrates 1A and 1B.
A spacer (not shown) made of a non-magnetic material such as is formed by sputtering. Next, the pair of substrates 1A and 1B are faced and the metal thin films 4 are butted against each other, and the track regulating recess 8 is filled with low melting point glass 11 and bonded (gap bonding, FIG. 1g).

After the gap bonding described above, the tape sliding surface 5 is cylindrically polished to finish the tape sliding surface 5 into a curved surface (FIG. 1h).

Next, a large number of chip-shaped magnetic cores are cut out by diagonally slicing so that the magnetic gap g takes a predetermined azimuth angle with respect to the tape sliding direction.
Figure i]. At this time, the chip of the magnetic head is cut out by a predetermined width around the gap part, so only the 6 parts of the thin film forming surface and the 2 parts of the sloped surface in the vicinity remain as a finished product, and the outside part is cut off. Therefore, even if a crack occurs on the flat gap facing surface 3, it will not be a problem.

After that, it is inspected and installed on the support head base, and the sliding surface is finished to improve its conformability in the track direction, and then the wire is wound [Fig. 1j].

Note that as the metal thin film material, an amorphous alloy such as a Co-Zr-Nb amorphous alloy or another metal with a high saturation magnetic flux density can be used.

(Effects of the Invention) As is clear from the above description, the present invention provides an inclined surface in the opposite direction to the thin film forming surface on the substrate surface facing the sputtering direction, for example, the gap facing surface, in close proximity to or adjacent to the thin film forming surface. Since the metal thin film is formed by sputtering after forming, the coarsest metal thin film is formed on the inclined surface due to the orientation with respect to the target, and the denser metal thin film is formed on the surface facing the gap. Cut off the influence of internal stress that occurs in Therefore, no cracks occur in the portion of the thin film forming surface 6 that will ultimately remain as a magnetic head and in the vicinity of the substrate 1 [see FIG. 2B] and FIG. 3B].

Therefore, deterioration of the magnetic properties and mechanical properties of the magnetic head can be prevented, and the yield of manufacturing the magnetic head can be improved and manufacturing costs can be reduced.

[Brief explanation of drawings]

FIG. 1 is a processing flow diagram explaining the magnetic head manufacturing method according to the present invention, and FIGS. 2A, B, and C show an example of a head substrate for implementing the method of the present invention.
A is an enlarged sectional view showing the substrate shape before sputtering near the thin film forming surface, B is the substrate shape after sputtering, C is an enlarged sectional view showing the substrate shape when cracks occur, and FIGS. 3A and 3B show other examples. A is an enlarged sectional view showing the substrate shape before sputtering, B is an enlarged sectional view showing the substrate shape after sputtering, FIG. 4 is an enlarged sectional view showing the substrate shape after sputtering, showing another embodiment of the present invention, and FIG. 5 is an enlarged sectional view showing the substrate shape after sputtering. A and B are enlarged sectional views showing the shape of a substrate after sputtering according to still another example. FIG. 6 is an enlarged sectional view showing a state in which cracks occur in the substrate of a magnetic head manufactured by a conventional method, and FIG. 7 is an explanatory view showing a conventional method of manufacturing a magnetic head. 1... Substrate, 2... Inclined surface, 3... Substrate surface facing the sputtering direction/gap opposing surface, 4
...metal thin film, 6...thin film formation surface.

Claims (1)

[Scope of Claims] 1. Manufacture of a magnetic head in which a pair of substrates each having a thin film formation surface and a metal thin film formed by sputtering on the thin film formation surface are butted together to form a magnetic gap using the space between the metal thin films. In the magnetic method, an inclined surface in a direction opposite to the thin film forming surface is formed on a substrate surface that is close to or adjacent to the thin film forming surface and facing the sputtering direction, and then sputtering is performed to form a metal thin film. Head manufacturing method. 2. The magnetic head manufacturing method according to claim 1, wherein the inclined surface is a triangular groove. 3. The magnetic head manufacturing method according to claim 1, wherein the inclined surface is continuous with an adjacent track groove.