JPH0782622B2 - Magnetoresistive magnetic head - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetoresistive (hereinafter referred to as MR) effect type magnetic head used in a magnetic disk device, a magnetic tape device, etc., and particularly, an NR element is a magnetic shield layer via an insulating layer. The present invention relates to a shield type magnetoresistive effect magnetic head having a sandwiched structure.

[0002]

2. Description of the Related Art FIG. 2 is a schematic view of a conventional shielded magnetoresistive head having an MR element sandwiched between magnetic shield layers with an insulating layer interposed therebetween. The lower shield film is formed on the alumina film formed on the substrate to form a pattern. An insulating film such as SiO ₂ or alumina is formed thereon, and an MR element is formed thereon. Further, an electrode is formed from gold, tungsten, tantalum, or the like, an insulating film is formed, and then an upper shield film is formed to form a pattern. Conventionally, a permalloy film has been used as a shield material. For example, Journal of Applied Physics 6
7: 4847. (J. Appl. P
hys. 67 (9), pp4847, 1990) or JP-A-61-248211.

However, since the hardness of the permalloy film is as low as about 200 in Vickers hardness, uneven wear between the permalloy film and the substrate occurs during polishing of the medium-opposing surface. The permalloy film causes so-called film droop and presses the MR element film. It caused problems such as doing and deforming. This allows
Regeneration efficiency was lowered and production yield was lowered.

Further, the permalloy film has a maximum saturation magnetic flux density of 10 KG, and a film thickness of about 1 μm was required for effective magnetic shielding. Therefore, the step due to the lower shield becomes large, and the insulation between the lower shield film and the MR element film cannot be obtained unless the insulating film on the lower shield is sufficiently thick. Furthermore, due to the step difference due to the lower shield, MR
The conduction failure of the element film and the electrode film was likely to occur. In order to solve this problem, as shown in FIG. 3, a method of forming an insulating layer in advance at the same height as the lower shield, burying the insulating layer, and then forming the insulating layer was also considered. However, this method complicates the manufacturing process. The complicated manufacturing process has led to a reduction in manufacturing yield.

[0005]

SUMMARY OF THE INVENTION The present invention is based on uneven wear due to the shield film, physical damage to the MR element film, and a step of the shield film, particularly the lower shield film in FIG. Poor insulation between lower shield film and MR element film, M
The object of the present invention is to solve the problem of poor conduction of the R element film and the electrode film without complicating the processing process, to stabilize the efficiency of the shield type magnetoresistive head and to improve the manufacturing yield.

[0006]

[MEANS FOR SOLVING THE PROBLEMS] MR in which electrodes are in contact
In a magnetoresistive effect magnetic head having a structure in which an element is sandwiched by magnetic shield layers with an insulating layer interposed between them, the magnetic shield layers are FeMN (M is at least one selected from Ta, Zr, Nb, Hf, and Ti). Element, and N is nitrogen) as a main component. F
If eMN is expressed with the composition of _{Fe x M y N z, x} , y,
When z is atomic%, 72 ≦ x ≦ 82, 8 ≦ y ≦ 13, 1
It is optimal to satisfy 0 ≦ z ≦ 15 and x + y + z = 100. Furthermore, this soft magnetic material is an aggregate of crystal grains in a body-centered lattice, the average grain size of the crystal grains is 10 nm or less, and there is no fixed rule in the crystal axis direction of each crystal grain. Is desirable.

Regarding FeMN, Japanese Patent Application No. 4-9467
No. 5 (filed on April 15, 1992) and C433 (p5-5) of the 1992 IEICE Spring Conference
See 3).

[0008]

According to the inventors' study, the FeMN film has a high saturation magnetic flux density of 15 KG or more, a high magnetic permeability of 3000 or more at 1 MHz, and a coercive force of 0.10 e or less. That is, it has suitable magnetic properties as a magnetic shield material. Furthermore, the Vickers hardness is as high as about 1000, which is extremely high hardness.

From these properties, by using the FeMN film as the shield material of the shield type MR head, the uneven wear and the physical damage to the MR element film due to the medium facing surface polishing which are generated in the permalloy film are suppressed. . Furthermore,
Since the saturation magnetic flux density is 1.5 times or more higher than that of the permalloy film, the shield film thickness can be reduced to 1 / 1.5. From this, the problems such as the insulation failure between the lower shield film and the MR element and the conduction failure between the MR element film and the electrode film due to the step of the lower shield film in FIG. 2 are solved without complicating the processing process, It is possible to stabilize the efficiency of the shield type magnetoresistive head and improve the manufacturing yield.

[0010]

EXAMPLE FIG. 1 shows a shield type MR head according to the present invention. For comparison, the one shown in FIG. 2 using a permalloy film as a shield material was prepared. Substrate 1 is AlTiC (Al
₂ O ₃ -Tic) was used. As head specifications, the track width is 8 μm, the shield width is 36 μm, the distance between the MR element film 5 and the upper shield 8 is 0.3 μm, and the MR element film 5 and the lower shield 3 are
The gap was 0.2 μm, the MR film (permalloy) thickness was 40 nm, the shunt bias film thickness was 60 nm, the intermediate film thickness was 20 nm, and the device width was 5 μm. When a permalloy film is used as the shield material (Fig. 2), the film thickness is 1μ.
m, 8.5 at% as a FeMN film in the case of the present invention
When using a Ta-13 at% N-residual Fe film (FIG. 1)
The film thickness was set to 0.65 μm. The saturation magnetic flux density of the permalloy film was 9.5 KG and that of the FeTaN film was 16 KG.

When the medium facing surface was polished, the permalloy film shield had a large step with the alumina film, and the uneven wear of the permalloy film was remarkable. Furthermore, the permalloy film causes so-called film sagging, which physically presses the MR element film. It is considered that this is because the hardness of the permalloy film is as low as about 200 in Vickers hardness, which is significantly lower than the hardness of about 1000 for the alumina film. In the case of the FeTaN film shield, almost no step difference with the alumina film was observed, and there was no physical damage to the MR element film. It is considered that this is because the hardness of the FeTaN film is as high as that of the alumina film. Even if the composition of the FeTaN film is different from the composition used as the shield film this time, the composition has a Vickers hardness of 1 as long as the composition is in a composition range having good soft magnetic characteristics.
Since it is as high as about 000, the same effect can be obtained. Further, as M, an element other than Ta, that is, Zr, Nb, H
If at least one kind of element selected from f and Ti is used, the saturation magnetic flux density is as high as 15 KG or more, and the same effect can be obtained.

When the FeTaN film is used as the shield material, the shield film thickness becomes thin as shown in FIG. 1, so that the step due to the lower shield becomes smaller than that in FIG. 2 which uses the permalloy film. From this, it is possible to reduce failures due to the insulation failure between the lower shield film and the MR element film due to the step of the lower shield film and the failure in conduction between the MR element film and the electrode film, and to stabilize the head efficiency and improve the manufacturing yield. did it. Fe
Even if the composition of the TaN film is other than the composition used as the shield film this time, the same effect can be obtained because the saturation magnetic flux density is as high as 15 KG or more as long as the composition is in a composition range with good soft magnetic characteristics. If M is an element other than Ta, that is, at least one kind of element selected from Zr, Nb, Hf, and Ti, the saturation magnetic flux density is as high as 15 KG or more, and the same effect can be obtained. .

[0013]

According to the present invention, uneven wear of the shield film and physical damage to the MR element film due to polishing of the medium facing surface, which occurred when the permalloy film was used as the shield material of the MR head, were suppressed. . Furthermore, since the saturation magnetic flux density of the FeMN film is 1.5 times higher than that of the permalloy film, the shield film thickness can be reduced to about 1 / 1.5, and The problems such as poor insulation between the shield film and the MR element film and poor continuity of the MR element film and the electrode film could be solved without complicating the processing process. As described above, the efficiency of the shield type magnetoresistive head was stabilized and the manufacturing yield was improved.

[Brief description of drawings]

FIG. 1 is a diagram showing a medium facing surface of a shielded magnetoresistive head according to the present invention.

FIG. 2 is a diagram showing a medium facing surface of a conventional shielded magnetoresistive head.

FIG. 3 is a diagram showing a medium facing surface of a conventional shielded magnetoresistive head.

[Explanation of symbols]

 1 Substrate 2 Alumina Layer 3 Lower Shield 4 Insulating Layer 5 MR Element Film 6 Electrode 7 Insulating Layer 8 Upper Shield

Claims (1)

[Claims] 1. A magnetoresistive effect magnetic head having a structure in which a magnetoresistive element in contact with an electrode is sandwiched by magnetic shield layers with an insulating layer interposed between the magnetic shield layers.
A magnetoresistive effect magnetic head comprising a soft magnetic material containing eMN (M is at least one element selected from Ta, Zr, Nb, Hf, and Ti, N is nitrogen) as a main component. .