JPS5837606B2 - thin film magnetic head - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a thin film magnetic head used in magnetic disk drives and the like.

In recent years, so-called thin-film magnetic heads, which form magnetic circuits and recording/reproducing coils using thin film formation techniques such as vapor deposition, sputtering, and plating, and pattern formation techniques by etching, have the potential for batch manufacturing and high dimensional accuracy. Therefore, it is attracting attention as having the potential for lower cost and higher performance.

In order to realize high-density recording by applying this as a levitating magnetic head to a magnetic disk device, etc., the transducer part, which consists of the magnetic circuit part that makes up the ring core and the recording/reproducing coil part, must be made levitating by some method. It needs to be mechanically coupled to the slider.

In a normal thin-film magnetic head, a transducer chip is formed by arranging a large number of thin-film transducers on a substrate made of silicon crystal or ceramic. Each chip is cut into pieces, and each chip is glued to the slider using an organic adhesive made of epoxy resin or the like.
Thereafter, the slider assembly is prepared by polishing so that the floating surface of the slider and the surface of the transducer pole are flush with each other.

However, in areas where the recording density of magnetic disk devices has improved and the floating amount of the slider assembly is micron or less, the amount of swelling of the organic adhesive due to moisture absorption is relatively large, and the coefficient of thermal expansion has decreased. is larger than the material of the slider and substrate, so even if aging or other treatments or precision polishing are performed, changes in environmental conditions such as temperature and humidity during use will cause the relative relationship between the slider and chip to deteriorate. It becomes difficult to avoid irreversible and temporal changes in the target position.

In addition, the appearance of such fluctuations is difficult to control because it largely depends on the application and distribution state of the organic adhesive.

Normally, the amount of variation due to the above reasons is 0.2 to 1 micron, and when the flying height of the slider assembly is less than 1 micron, it not only greatly impairs the uniformity of performance as a magnetic head, but also causes damage to the storage medium. Mechanical contact with the magnetic disk is likely to occur, which may cause a fatal failure.

In contrast, the countermeasure adopted by conventional magnetic heads using ferrite cores is the glass fusion method, but when this method is applied to thin-film magnetic heads, it is necessary to use a permalloy metal magnetic material and a conductive material made of gold or copper. Because of the use of these materials, there is a risk that a diffusion phenomenon may occur between the materials during glass fusing treatment in a high-temperature furnace, or undesirable results may occur in terms of magnetic and mechanical properties due to residual stress.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a thin film magnetic head in which, apart from the above-mentioned drawbacks, there is almost no relative positional variation between the slider chip and the slider chip regardless of the environmental conditions. It is an object of the present invention to provide a thin film magnetic head that requires fewer man-hours and is therefore inexpensive.

According to the present invention, the object can be achieved by constructing the slider of the thin-film magnetic head using the blank plate of the transducer.

Hereinafter, the present invention will be explained in detail using the drawings.

FIG. 1 shows one embodiment of the present invention and is a perspective view of a slider assembly in a one-turn thin film head.

In the same figure, 1 is the slider assembly, 10 is the transducer part, 2 is the slider, 3 is the floating surface of the slider 2, and 4 is the slider assembly.
is the magnetic circuit part of the transducer, 5 is the recording/reproducing coil part of the transducer, 6 is its leader line part, 7
is a groove for coupling with a slider support mechanism (not shown).

FIG. 2 is an enlarged view of a part of the transducer portion 10, which is a needle-view view taken along the line AA in FIG. 1.

In the figure, 41 is the lower core portion of the magnetic circuit portion 4;
Similarly, 51 is an upper core portion, and 51 is a void portion.

Referring to FIGS. 1 and 2, the transducer section 10 in this embodiment includes four magnetic circuit sections 4 and a one-turn recording/reproducing coil section 5 having lead wire sections 6 on both sides of each magnetic circuit section 40. This is formed on a blank plate that also serves as the material for the slider 2.

The magnetic circuit section 4 consists of a lower core section 41 and an upper core section 42 made of permalloy, and a gap section 51 made of gold, and a part of the recording/reproducing coil section 5 is inserted into this gap section 51. I am doing it.

The leader line portions 6 are connected to a recording/reproducing circuit (not shown), and when selecting an arbitrary magnetic circuit portion 4, ie, a track, one pair of the leader line portions 6 on both sides of the magnetic circuit portion 4 are selected.

The slider 2 is made of alumina in this embodiment, and has a thickness of 5 mm as a base plate on which many transducers are formed.

The thickness of each thin film at the transducer portion is approximately 2
It is micron, and this part is exaggerated in FIGS. 1 and 2.

FIG. 3 is a diagram showing a floating state of the slider assembly 1 as described above, and 8 is a magnetic disk.

The magnetic disk 8 is rotating at a speed U in the direction of the arrow, and a pressing force W is applied to the slider assembly 1, and hm is applied near the transducer portion 10.
It is levitating with a levitation amount of

FIG. 4 is a diagram illustrating a situation in which a large number of transducer parts 10 are arranged and formed on a blank plate.
is an alumina blank plate with a thickness of 5 mm.

A large number of transducer parts 10 are aligned and arranged on a blank plate 20 as shown in FIG. 4 and manufactured in bulk, and each transducer part is cut into units of 100 to form chips.

In this chip, if the surface on which the transducer portion 10 is formed and the surface on which the magnetic circuit portion 4 is arranged, that is, the levitation surface 3, is precisely polished, the first
The slider assembly 1 as shown in the figure is obtained.

Therefore, by doing the above, firstly, the part of the base plate 20 in the chip forms the slider 2, and unlike conventional organic adhesives, irreversible positional fluctuations over time can be avoided and extremely A stable and uniform slider assembly 1 can be obtained.

Second, since there is no need to separately manufacture a slider and bond a chip to it as in the conventional method, the number of manufacturing steps can be reduced and a slider assembly can be obtained at low cost.

In a conventional thin film magnetic head, the thickness of the base plate 20 is 0.
．． The thickness was approximately 5 to 1 mm, but in this embodiment, the thickness is set to 5 mm in order to secure the necessary floating area on the floating surface 3 of the slider 2.

This level of thickness is fully achievable even with current technology, does not involve any difficulty, and hardly increases cost.

The above embodiments as shown in FIGS. 1 and 2 are intended for a one-turn thin film head, but the transducer portion 10 may be a multi-turn thin film transducer,
For example, US Pat. No. 3,549,825 (December 1970)
(Registered on the 22nd of May) or No. 3344237 (Registered on the 22nd of May)
It is clear that the spirit of the present invention can be realized by replacing the transducer as disclosed in the US Pat.

The embodiments of the present invention have been described in detail above, and it has been shown that the objects of the present invention can be achieved. It goes without saying that the dimensions, furthermore, the arrangement, configuration, etc. of the transducer portion 10 on the blank plate 20 may be modified without departing from the spirit of the present invention. Ceramic, glass, or other protective coatings may be applied to the surface of the transducer portion 100 of the slider assembly 1 as shown at processing temperatures below 400° C., and the foregoing description does not limit the scope of the present invention. It is clear that this is not the case.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of a slider assembly according to an embodiment of the present invention, FIG. 2 is an enlarged perspective sectional view of the transducer portion of the slider assembly shown in FIG. 1, and FIG. 3 is a levitation of the slider assembly. FIG. 4 is a diagram showing the arrangement of the transducer portion on the substrate. In these figures, 1 is a slider assembly, 2 is a slider, 3 is a floating surface, 4 is a magnetic circuit portion, 5 is a recording/reproducing coil portion, 6 is a lead wire portion thereof, 8 is a magnetic disk, 10 is a transducer portion, 20 is a substrate.

Claims (1)

[Claims] 1. A transducer including a large number of thin film magnetic heads that are formed on a silicon, ceramic, etc. substrate in one step using thin film forming techniques such as vapor deposition, sputtering, and plating, and pattern forming techniques such as etching. The part is cut into necessary units to form a transducer chip, and the surface of the chip on which the transducer gap part perpendicular to the plane in which the transducer part is formed is aligned is polished as a floating surface. A method of manufacturing a thin film magnetic head, characterized in that a slider assembly is formed by doing so.