JPH02239416A - Magneto-resistance effect type head - Google Patents

Abstract

PURPOSE:To prevent the degradation of the reproduction efficiency arising from the trend toward narrower tracks and the generation of Barkhausen noises by forming a shunt conductor of a soft magnetic material having a small magneto-resistance effect and laminating a magneto-resistance effect element having a prescribed track width on the shunt conductor so as to come into contact therewith. CONSTITUTION:The shunt conductor 2 consists of the soft magnetic material having the small magneto-resistance effect and the magneto-resistance effect element (MR element) 1 having the prescribed track width is laminated on the shunt conductor 2 so as to come into contact therewith. Since the MR element 1 is lined with the soft magnetic shunt conductor 2 in such a manner, the diamagnetic field in the track width direction of the MR element 1 is decreased and the generation of a reflux magnetic domain is suppressed. The axis of easy magnetization is imparted in the track width direction even in the narrow track width in this way and the degradation in the reproduction efficiency is prevented. Since the unnecessary magnetic domain does not exist, the generation of the Barkhausen noise is prevented as well.

Description

[Detailed Description of the Invention] [Summary] The purpose of the present invention is to prevent a reduction in the reproduction output and the occurrence of Barkhausen noise due to the formation of interlocking tracks in magnetoresistive reproduction heads used in magnetic disk devices, magnetic tape devices, etc. In a shunt bias type magnetoresistive head comprising a magnetoresistive element and a shunt conductor for applying a bias magnetic field to the magnetoresistive element, the shunt conductor is made of a soft magnetic material with a small magnetoresistive effect. A magnetoresistive element having a predetermined track width is laminated so as to be in contact with the shunt conductor.

[Field of industrial use]

The present invention relates to a magnetoresistive reproducing head (hereinafter referred to as an MR head) used in a magnetic disk device, a magnetic tape device, or the like.

In recent years, high-performance magnetic heads have been required as the capacity of magnetic recording devices, which are external storage devices for computers, has increased.
An MR head that can obtain high output regardless of the speed of the recording medium is attracting attention as a device that satisfies this requirement.

[Conventional technology]

The structure of the conventional shunt bias type MR head is
As shown in the figure. In the figure, ■ is a magnetoresistive element (hereinafter referred to as MR element), 2 is a shunt conductor provided in contact with the MR element, and 3.3' is a lead-out conductor.
It is bonded to both ends of the element. 4 and 4' are magnetic shield bodies. A sense current j is passed through the bowed conductor 3.3'.

Further, the MR element 1 is given anisotropy so that its track width direction (the direction of the longitudinal force of the element) is the magnetic easy axis. In addition, in order to cause the MR element l to operate linearly with respect to the magnetic field coming from the medium, the magnetic field generated by the current flowing through the shunt conductor 2 made of Ti or Mo and the MR element l
A bias is applied at an angle of 45° with respect to the longitudinal direction of the MR element due to the leakage magnetic field from the surface of the shield body 4.4' magnetized by the current magnetic field from the shunt conductor 2. The recording medium 5 moves under this head in the X direction.

[Problem to be solved by the invention]

In the above-mentioned conventional MR head, it is necessary to shorten the MR element 1 in order to improve the track density, but as a result, the demagnetizing field in the track width direction (longitudinal direction of the MR element) becomes stronger, and the MR element 1 As shown in Figure 3, reflux magnetic domains are generated to reduce the static magnetic energy.As a result, there is a problem that the regeneration efficiency decreases or Barkhausen noise occurs due to discontinuous movement of the magnetic domains. occurs.

SUMMARY OF THE INVENTION In view of the above-mentioned conventional problems, it is an object of the present invention to provide an MR head that prevents the reduction in reproduction efficiency and the generation of Barkhausen noise caused by the use of interlocking tracks.

[Means to solve the problem]

In order to achieve the above object, the MR head of the present invention employs a shunt bias type magnetoresistive system comprising a magnetoresistive element 1 and a shunt conductor 2 for applying a bias magnetic field to the magnetoresistive element 1. On the right side of the effect type head, the shunt conductor 2 is made of a soft magnetic material with a small magnetoresistive effect, and a magnetoresistive element 1 having a predetermined track width is laminated so as to be in contact with the shunt conductor 2. shall be.

[For production]

By lining the MR element 1 with a soft magnetic shunt conductor 2, the demagnetizing field in the track width direction of the MR element 1 is reduced, and the generation of free-flow magnetic domains is suppressed. As a result, even in a narrow track width, a magnetic easy axis can be provided in the track width direction, and a reduction in reproduction efficiency can be prevented.

Furthermore, since there are no unnecessary magnetic domains, Barkhausen noise is also prevented from occurring.

〔Example〕

FIG. 1 is a diagram showing an embodiment of the present invention.

In the same figure, 4.4' is a magnetic shield body, and amorphous Co is between these two magnetic shield bodies 4.4'.
An MR element 1 having a predetermined track width backed by a shunt conductor 2 made of Zr is disposed, and the shunt conductor 2
A lead conductor 3.3' is connected to both ends of the wire.

In this embodiment configured as described above, the rate of change in magnetoresistance of the amorphous CoZr used for the shunt conductor 2 is about two orders of magnitude smaller than that of Nice, which is the MR element 1, so that it does not affect the reproduced signal of the MR element. Never. In addition, since this amorphous CoZr has excellent soft magnetic properties such as high magnetic flux density and high magnetic permeability, it can reduce the demagnetizing field of the MR element 10, suppress the generation of reflux magnetic domains, and prevent a decrease in reproduction efficiency and Barkhausen noise. can.

In the example, the shunt conductor is made of amorphous C.
Although oZr was used, similar effects can be obtained using sendust or FeSi.

〔Effect of the invention〕

As explained above, according to the present invention, it is possible to suppress the generation of freewheeling magnetic domains in the MR element within the width of the sandwich track, thereby preventing a reduction in reproduction output and the occurrence of Barkhausen noise. It can contribute to higher density.

[Brief explanation of drawings]

Fig. 1 is a diagram showing an embodiment of the present invention, Fig. 2 is a diagram showing a conventional shunt bias type magnetoresistive head, and Fig. 3 is a diagram for explaining the problem to be solved by the invention. be. In the figure, 1 is a magnetoresistive element (MR element), 2 is a shunt conductor, 3.3' is a lead-out conductor, and 4.4' is a magnetic shield. Perspective view showing an embodiment of the present invention 1... Magnetoresistive elements 4, 4'... Magnetic shield body

Claims (1)

[Claims] 1. A magnetoresistive element (1) and a magnetoresistive element (
A shunt conductor (2) for applying a bias magnetic field to (1)
), the shunt conductor (2) is made of a soft magnetic material with a small magnetoresistive effect, and the shunt conductor (2) has a magnetoresistive effect having a predetermined track width. A magnetoresistive head characterized in that elements (1) are stacked so as to be in contact with each other.