JPH0799115A - Magnetic alloy film and magnetic head using this - Google Patents

Abstract

PURPOSE:To materialize a magnetic alloy film which is excellent in corrosion resistance and shows soft magnetic property and can be used as a material for a magnetic head by modulating the composition of the magnetic alloy film containing nitrogen, in the direction of film thickness. CONSTITUTION:For a magnetic film containing nitrogen, the atomic composition rate is made {[(COaNbbZrc)1-d/100Fe4]1-e/100Cue}10-f/100Nf, and besides the compositions of Co, Nb, Zr, Fe, Cu, and N are modulated, respectively, in the directions of films. But, a, b, c, d, e, and f express atom %, and they are as follows: 82<=a<=94, 6<=b+c<=18, 0.1<=d<=5.0, 1<=e<=5.0, 1<=f<=15, a+b+c=100. For the magnetic alloy film containing nitrogen of such composition, the corrosion resistance can be improved sharply while fulfilling the magnetic properties such as high saturation magnetic density, low coercive force, high permeability, low saturation magnetostriction, etc. And, soft magnetic property appears by applying heat treatment in rotating magnetic field in vacuum atmosphere to the magnetic alloy film 2 containing nitrogen, thus a MIG head shown in the figure is manufactured.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic alloy film containing nitrogen suitable for a magnetic head and the like and a magnetic head using the same.

[0002]

2. Description of the Related Art In order to realize a high recording density in magnetic recording, it is required to increase the coercive force of a recording medium and the magnetic material for a magnetic head to have a low coercive force, a high magnetic permeability and a high saturation magnetic flux density. A magnetic alloy film containing nitrogen, which has been invented in recent years (for example, JP-A-62-210607 and JP-A-63-57758).
(Japanese Laid-Open Patent Publication No. 2003-242242) has various characteristics that a conventional amorphous alloy film or nitride film does not have, and that it is thermally stable while maintaining a high saturation magnetic flux density.

Further, by adding a certain kind of element, the composition region FIG. 3 in which the saturation magnetic flux density can be further increased without increasing the absolute value of the saturation magnetostriction, has been found (Japanese Patent Application No. Hei. 8910). here,
In the prior art, the nitrogen composition is 12 atomic percent and F
A magnetic characteristic composition diagram of a magnetic alloy film containing nitrogen having an e composition of 1 atomic percent after heat treatment in a rotating magnetic field at 600 ° C. is shown. Hatched portion in the figure saturation magnetic flux density is more than 12 kG, the coercive force is 1Oe less permeability of 500 or more at a measuring frequency of 1 MHz, shows a composition region in which the saturation magnetostriction satisfies the magnetic properties of 1 × 10 ^-6 or less ± .

[0004]

However, as a result of subsequent studies, the magnetic alloy film containing nitrogen as described above does not always have perfect corrosion resistance, and there is a possibility that corrosion may occur in an acidic solution to deteriorate magnetic properties. There is a problem.

The present invention solves the above problems,
An object of the present invention is to realize a magnetic alloy film containing nitrogen, which has a high saturation magnetic flux density, excellent corrosion resistance and soft magnetism, and which can be used as a material for a magnetic head.

[0006]

The nitrogen-containing magnetic film according to the present invention has an atomic composition ratio of {[(Co _a Nb _b Zr _c ) _{1−d / 100} Fe _d ] _{1-e / 100} C.
u _e } _{1-f / 100} N _f , and each composition of Co, Nb, Zr, Fe, Cu, and N may be modulated in the film thickness direction.

However, a, b, c, d, e and f represent atomic percentages, and 82≤a≤94 6≤b + c≤18 0.1≤d, respectively.
≦ 5 0.1 ≦ e ≦ 5 0.1 ≦ f ≦ 15 a + b + c
= 100.

[0008]

[Operation] In other words, to obtain a sufficiently large saturation magnetic flux density,
It must be a ≧ 82. However, the magnetic alloy film containing nitrogen in the present invention must be heat-treated in a magnetic field in order to obtain excellent magnetic properties, and undergoes heat treatment such as glass fusion during magnetic head processing. In order to obtain sufficient thermal stability such that the magnetic characteristics do not deteriorate, a ≦ 94 must be satisfied.

The presence of nitrogen is indispensable in order to realize the sufficient thermal stability, high saturation magnetic flux density, low coercive force and saturation magnetostriction, and it must be f ≧ 0.1. However, the presence of excess nitrogen must be f.ltoreq.15, since the excess nitrogen will sputter during heat treatment and impair the surface properties of the magnetic alloy film.

To obtain lower coercive force and saturation magnetostriction,
Optimal Nb and Zr composition exists, which is 6 ≦ b + c
≦ 18.

To increase the saturation magnetic flux density and keep the absolute value of the saturation magnetostriction at a sufficiently low value, d
It is effective to add Fe of ≧ 0.1. However, excessive F
The addition of e is counterproductive and must be d ≦ 5.

In addition to this, in order to obtain corrosion resistance, e ≧ 0.1
It is effective to add Cu. However, the addition of excess Cu hinders obtaining a high saturation magnetic flux density, and must be e ≦ 5.

Finally, of course, a + b + c = 1
Must be 00. The period of compositional modulation is as described above (Japanese Patent Laid-Open No. 62-210).
No. 607) 1000 Å or less is desirable.

[0014]

Embodiments of the present invention will be described below with reference to the drawings.

(Example 1) Using an RF bipolar electrode sputtering device, the composition is [(Co ₉₀ Nb ₈ Zr ₂ ) in atomic percent.
_A target of _0.99 Fe ₁ ] _0.90 to ₁ Cu ₀ to ₉ was sputtered in an atmosphere in which N ₂ gas was periodically introduced into Ar gas to produce a magnetic alloy film containing nitrogen. Subsequently, this film was subjected to a heat treatment in a rotating atmosphere in a rotating magnetic field, so that the soft magnetic characteristics were revealed. Table 1 shows film forming conditions of this example, Table 2 shows magnetic field heat treatment conditions, and Table 3 shows saturation magnetic flux density and corrosion resistance after magnetic field heat treatment. The corrosion resistance was judged to be excellent, good or bad depending on the rust generation condition after the sputtered film was immersed in pure water and left at room temperature for 24 hours. It can be seen that as the amount of Cu added increases, the occurrence of rust is suppressed and the corrosion resistance is significantly improved. However Cu
When the added amount of E becomes e> 5, the saturation magnetic flux density becomes small.

[0016]

[Table 1]

[0017]

[Table 2]

[0018]

[Table 3]

Magnetic characteristics such as high saturation magnetic flux density, low coercive force, high magnetic permeability and low saturation magnetostriction are required for the soft magnetic alloy film for magnetic head. Exact values of these magnetic characteristics cannot be obtained unless the magnetic recording system as a whole is determined, but in general, the coercive force is 1 Oe or less and the saturation magnetostriction is ±
It is said that the higher the magnetic permeability is within 1 × 10 ⁻⁶ , the higher the magnetic permeability is at several hundreds of MHz at the measurement frequency of 1 MHz, and the higher the saturation magnetic flux density is. One of the greatest features of the magnetic alloy film containing nitrogen in the present invention is that it has a high saturation magnetic flux density of 12 kG or more, which is not obtained with conventional Co-based amorphous alloys or sendust materials, and is thermally stable. That is.

As a result, the composition is {[(Co ₉₀ Nb ₈ Z
_{r 2) 0.99 Fe 1] 0.95} ~ 1 Cu 0 ~ 5} 0. 88 N 12 and 1,
It is understood that the nitrogen-containing magnetic alloy film whose composition is modulated in the film thickness direction at a cycle of 000 Å or less has preferable magnetic characteristics as a magnetic film for a magnetic head.

Example 2 The composition of the present invention is {[(C
o₉₀Nb₈Zr₂)_0.99Fe₁]_0.99Cu₂}_0.88N ₁₂ Over
And conventional technology [(Co₉₀Nb₈Zr₂)_0.99Fe₁]
_0.88N₁₂ The magnetic alloy film containing nitrogen shown in
A film was formed on Mn-Zn ferrite under the conditions of (Table 1) of
Then, heat treatment in a rotating magnetic field was performed under the conditions of (Table 1),
A MIG head having the shape shown in FIG. These two f
Attach the pad to a normal VTR deck and attach metal tape
The properties were compared (Table 4). Then these two
96 in a magnetic head at 60 ° C and 90% relative humidity
Leave it for a while and compare the characteristics in the same way (Table 4).
Showed. However, both results are relative at a frequency of 9 MHz.
The magnetic gap is 0.25 μm, and the
Width of 20 μm, recording wavelength of 0.83 μm, relative velocity
It was set to 5.8 meters / second.

[0022]

[Table 4]

As is clear from Table 4, the magnetic head using the magnetic alloy film containing nitrogen according to the present invention has better recording characteristics than the magnetic head using the magnetic alloy film containing nitrogen according to the prior art. Little deterioration. This is probably because the deterioration of magnetic properties due to corrosion was suppressed.

(Embodiment 3) Under the same conditions as in Embodiment 2, FIG.
A laminated magnetic head having the shape shown in was prepared. However, the substrate used was a TiMgNiO substrate. These two magnetic heads were attached to a normal VTR deck under the same conditions as in Example 2, and their recording / reproducing characteristics were measured (Table 5). In this case as well, as is clear from (Table 5), the magnetic head to which the magnetic alloy film containing nitrogen having the composition according to the present invention is desired has good corrosion resistance.

[0025]

[Table 5]

[0026]

As is apparent from the above embodiments, according to the present invention, the magnetic alloy film containing nitrogen satisfies magnetic characteristics such as high saturation magnetic flux density, low coercive force, high permeability and low saturation magnetostriction. However, the corrosion resistance can be greatly improved. Further, the magnetic head using the magnetic material of the present invention can suppress deterioration of magnetic characteristics due to corrosion.

[Brief description of drawings]

FIG. 1 is a perspective view showing the configuration of an MIG head using a magnetic alloy film of the present invention.

FIG. 2 is a perspective view showing the configuration of the same laminated magnetic head.

FIG. 3 is a diagram showing a relationship between magnetic characteristics and composition of a conventional magnetic alloy film containing nitrogen.

[Explanation of symbols]

 1 Mn-Zn ferrite substrate 2 Magnetic alloy film containing nitrogen 3 Magnetic gap 4 Winding window 5 Bonding glass 6 TiMgNiO substrate

Claims (2)

[Claims] 1. {[(Co _a Nb _b Zr _c ) _{1−d / 100} Fe _d ].
_{1-e / 100} Cu _e } _{1-f / 100} N _f , and each composition of Co, Nb, Zr, Fe, Cu and N is modulated in the film thickness direction. A characteristic magnetic alloy film containing nitrogen. However, a, b, c, d, e and f represent atomic percentages, and 82 ≦ a ≦ 94 6 ≦ b + c ≦ 18 0.1 ≦ d, respectively.
≦ 5 0.1 ≦ e ≦ 5 0.1 ≦ f ≦ 15 a + b + c
= 100. 2. A magnetic head using the magnetic alloy film containing nitrogen according to claim 1 as a magnetic core.