JPS60138711A - Manufacture of magnetic head - Google Patents

Abstract

PURPOSE:To smooth the slide face in a short time and also to give annealing effects to the surface of slide by irradiating a laser to apply smoothing by surface heating after a magnetic head is polished mechanically. CONSTITUTION:The laser light from a Q switch pulse oscillation YAG laser 1 is irradiated onto several hundreds of magnetic head groups 3 after mechanical polishment at the same time through an optical system 2. Thus, the slide surface is melted by several hundreds Angstrom to make the ruggedness flat thereby giving the annealing effect.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to a method for manufacturing a magnetic head, and more particularly to a method for manufacturing a magnetic head in which a head sliding surface is further smoothed after polishing.

[Prior art] Traditionally, VTRs and computer memory disks.

Magnetic leads used for tape recorders etc.
In the final process of manufacturing, methods such as cylindrical grinding, surface grinding, tape lapping, etc. are used to polish the tip, that is, the sliding surface with the medium (the part indicated by the symbol A in Figure 1 (a)). . However, in these methods, fine irregularities of about Q, 1 p, m as shown in FIG. 1(b) usually remain on the sliding surface. This unevenness on the sliding surface causes fluctuations in the spacing loss between the head and the medium, causing problems in output characteristics, and furthermore, has the drawback of leading to damage to the surface of the medium.

For this reason, in a magnetic head that requires a high S/N ratio, a
Smoothing is performed over a long period of time using tape, etc., but this has the drawback of significantly increasing the production cost of the head.

In addition, conventional mechanical planar polishing of the sliding surface has the disadvantage that the magnetic material at the tip of the head is subjected to stress and changes in quality, resulting in deterioration of the magnetic properties in the vicinity of the sliding surface.

[Purpose] The present invention was made to eliminate the above-mentioned conventional drawbacks, and is characterized by smoothing the sliding surface in a short time and giving an annealing effect to the sliding surface. The purpose of this invention is to provide a method for manufacturing a magnetic head.

In order to achieve the above object, the present invention flattens the convex parts by heating the sliding surface using a heat source such as a laser beam and melting only a few hundred particles on the sliding surface. , a method of simultaneously filling the recesses is used.

[Example] Hereinafter, the present invention will be described in detail based on the example shown in the drawings.

[First Embodiment] FIG. 2 is a diagram for explaining an embodiment of the present invention.
AG laser, output 10100O, irradiation time 0
．． It is about 1 p.sec. A laser beam 11-1 from the YAG laser 1 is diffused through the optical system 2, and irradiates several hundred magnetic nodules 3 all at once.

Since the present embodiment is configured as described above, it is possible to obtain the effect that the laser annealing effect can be applied to a large number of magnetic heads at one time.

[Second Embodiment] FIG. 3 shows another embodiment of the present invention, and the reference numeral 4 in the figure is a continuous wave (CW) carbon dioxide laser. The output of this carbon dioxide laser 4 is about 50 mm. The laser beam passes through an optical system 5, an X-axis mirror 6, and a Y-axis mirror 7, and is focused to a diameter of about several tens of JLm.

The focused laser beam 8 scans over hundreds of magnetic heads 9 using an X-axis mirror 6 and a Y-axis mirror 7.

The scanning speed of the laser beam 8 is about 10 cm/sec, and therefore, in addition to the effect that laser annealing effect can be applied to a large number of magnetic heads as in the above-mentioned embodiment, the following effects are also obtained. can get.

Materials for the magnetic head in which the above-described embodiments can be implemented are limited to alloys, ferrite, silicon, and the like. However, in this embodiment, although the irradiation time of the laser beam 8 is 1 to 2 minutes, which is much longer than in the above-mentioned embodiment, it is possible to smooth the surface of the glass, and to protect thin-film magnetic heads, etc. The effect is that even plates made of glass can be processed.

[Third Embodiment] As another embodiment of the present invention, there is also a method of forming a carbon film by sputtering carbon onto the sliding surface of a magnetic head before heating it with a laser. When such a method is adopted, the heat absorption of the laser beam is improved. Therefore, for example, if this method is adopted in the embodiment shown in FIG. This results in extremely improved efficiency.

Furthermore, by sputtering carbon, it is possible to improve the lubricity between the magnetic head and the medium when the magnetic head is used.

[Fourth Embodiment] As another embodiment of the present invention, gold is deposited in N on the sliding surface of a magnetic head in a low vacuum state, and then a blackening phenomenon is caused, resulting in a blackened gold film. Another method is to apply a laser beam to the sliding surface and then wipe off the blackened gold.

Since this embodiment has a structure in which blackened gold is vapor-deposited on the sliding surface, the laser beam is efficiently absorbed, resulting in the effect of saving laser power and shortening the irradiation time. can get.

[Fifth Embodiment] Another embodiment of the present invention is to use a xenon flash lamp instead of heating the surface with a laser beam. In this case, the irradiation power density is about 5×10′ W/cm 2 , and therefore the treatment can be performed in an irradiation time of about several m5ec.

Since this example uses the method described above, the irradiation time is longer than in the case of a pulsed laser, but by arranging a large number of flash lamps, it is possible to uniformly irradiate a large area with light. As a result, it is possible to process a very large number of magnetic heads. Additionally, the device is simpler and more suitable for automation than when a laser is used.

Incidentally, FIG. 4 shows the unevenness of the surface after laser treatment. In the figure, the vertical axis represents the unevenness in units of λ, and the horizontal axis represents the amount of movement of the magnetic head on the sliding surface.
Shown in units. As you can see from this figure, the unevenness is 2
~300A.

Generally, spacing loss is expressed by the following equation.

In the above formula, I represents the recording wavelength, and D represents the spacing.

For example, if the input is 1, D has changed from the conventional 5ooA to 200A in the present invention.
This means that an improvement of 3 dB or more has been achieved.

[Effects] As is clear from the above explanation, according to the present invention, the sliding surface of the magnetic head is smoothed by using a laser annealing effect, so that the following effects can be obtained. .

(1) The extremely smooth sliding surface improves the lubricity between the magnetic head and the medium, resulting in improved running performance and improved wear resistance.

(2) Since the sliding surface is extremely smooth, fluctuations in the spacing between the magnetic head and the medium are reduced, and spacing loss is reduced, so the output of the magnetic head is stabilized.

(3) Due to the laser annealing effect, processing deterioration near the sliding surface can be removed, and as a result, the characteristics of the magnetic head are improved.

(4) Since ultra-precision polishing of the sliding surface can be performed in a short time, the manufacturing cost of the magnetic head is reduced.

[Brief Description of the Drawings] Figure 1 is a diagram explaining the surface unevenness of a conventional VTR head, and Figure 1 (&) is an enlarged view of the conventional VTR head.
Figure (b) is a diagram showing the unevenness of the sliding surface, and Figures 2 and 3 are diagrams explaining the method of smoothing the sliding surface surface using a laser.・Schematic diagram when a multi-pulse laser is used. Figure 3 is a schematic diagram when a continuous wave (CW) laser is used as the laser. Figure 4 shows the unevenness of the sliding surface after laser heat treatment. It is a line diagram. l...YAG laser-2,5...optical system 3.9...
・Magnetic head group 4... Carbon dioxide laser Figure 1 (CI) (b) Figure 2 Figure 3

Claims (4)

[Claims] (1) Magnetic head manufacturing method A method for manufacturing a magnetic head, characterized in that after polishing the sliding surface of the medium by a mechanical method, smoothing is performed by heating the surface by laser irradiation. (2) A method for manufacturing a magnetic head according to claim 1, characterized in that a carbon film is formed on the m-moving surface, and the carbon film serves as a lubrication improving film as well as a laser light absorbing film. . (3) The method of manufacturing a magnetic head according to claim 1, wherein blackened gold or blackened krypton is deposited on the sliding surface, and the deposited film is a laser light absorbing film. (4) A method for manufacturing a magnetic head, which comprises polishing the sliding surface of the medium by a mechanical method in the manufacturing process of the magnetic head, and then smoothing the surface by heating the surface using a xenon flash lamp. .