JPS6289311A - Magnetically soft thin film - Google Patents

Abstract

PURPOSE:To obtain the titled soft magnetic thin film having a high permeability, an excellent corrosion-resisting property, an excellent abrasion-resisting property of high degree of hardness and thermal stability without lowering the density of saturated magnetic flux and also without increasing magnetic coercive force by a method wherein nitrogen N is added to the magnetic thin film having Fe, Al and Ge as the main components, and the composition of component of the magnetic thin film is specified. CONSTITUTION:The composition of the titled soft magnetic thin film is indicated by the formula of FeaAlbGecNx (provided that the compositional ratio of a, b, c and x is indicated by atom%), each compositional range is 55<=a<=84, 1<=b<=31, 1<=c<=31, and 0.1<=x<=30, and excellent serviceability is given to the soft magnetic thin film of the composition of a+b+c+x=100. Pertaining to the compositional ratio N, it becomes invalid or the characteristics of the magnetic thin film are deteriorated in the compositional range other than the above-mentioned range. It is desirable that the magnetically soft thin film is manufactured by performing a vapor deposition method, an ion implanting method and the like. Also, as the method wherein nitrogen N is introduced into the magnetic thin film, there are the method in which vapor deposition and the like is performed in the atmosphere containing nitrogen gas and the method in which nitrogen N is introduced into the magnetic thin film using the compound, consisting of nitrogen N and at least a kind of element selected from the above-mentioned material, and the alloy of the remaining component as the source of evaporation.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a soft magnetic thin film suitable for use in, for example, a thin film magnetic head.

[Summary of the invention]

The present invention is a soft magnetic thin film made of nitrogen-containing Fe-An-Ge yarn, which has a small coercive force 1C and a sieve magnetic permeability μ due to its specific composition, and has particularly excellent corrosion resistance and hardness. This is what you get.

[Conventional technology]

In various magnetic recording and reproducing devices, demands for areal density recording and higher frequency are increasing, and in response to this, magnetic recording media with high saturation magnetization and high coercive force are used. As this type of magnetic recording medium, so-called metal tapes made of powder of ferromagnetic metals such as Fe, Co, and Ni, and so-called vapor-deposited tapes made of ferromagnetic metal materials deposited on a base film are used. It has reached this point.

Accordingly, magnetic heads for this type of magnetic recording medium are required to be made of head materials with high saturation magnetic flux density and high magnetic permeability, as well as having small magnetic anisotropy, zero magnetostriction, and coercive force. is small, and has the highest abrasion resistance possible as a head material, with zero resistance! l: It is required to have not only magnetic properties, but also chemical stability and better mechanical properties.

On the other hand, with the trend toward higher density recording, there is a need to narrow the recording track width (and thus the track width of the operating magnetic gear in the magnetic head). Thin-film magnetic heads using thin-film technology, in which a magnetic core is formed by depositing a soft magnetic thin film on a non-magnetic or magnetic substrate, are becoming increasingly popular.An example of this type of soft magnetic thin film is Pe+. AN+Si]
Sendust alloy@membrane, which is the next component, is attracting attention.

This Sendust alloy thin film has a high saturation magnetic flux density Bs
Since it has a relatively high hardness, it can be applied even to magnetic recording media having a residual magnetic flux density of 1r (1r), such as the metal tape mentioned above.

However, although this Sendust alloy 8 has relatively high hardness, it is inferior in wear resistance and corrosion resistance compared to, for example, ferrite materials. In addition, this Sendust alloy thin film has a relatively low resistivity, so when it is used as the core of a magnetic head, a decrease in magnetic permeability in the image frequency region due to so-called eddy currents1) becomes a problem. , there is a problem that sufficient reproduction output may not be obtained in the same frequency range.

In contrast, instead of using Sendust alloy thin film, a high saturation magnetic flux density Bs with less low magnetic permeability in the surface frequency region is used.
It has been considered to use an amorphous magnetic alloy material, but this amorphous magnetic alloy material has drawbacks in heat resistance, and its magnetic permeability deteriorates significantly due to long-term heating or thermal cycling. The efficiency of the department will deteriorate. Especially crystallization 1
11) Because of its high potency, it is not possible to apply temperatures of 500°C or higher for long periods of time.For this reason, in the manufacturing process of magnetic heads, for example, 500°C is used, such as glass Ni1t deposition.
There are problems such as that it is not preferable to use a process that requires treatment at a temperature of 00° C. or higher.

Under these circumstances, research into soft magnetic materials with even better soft magnetic properties has progressed, for example, Tatsuharu Yamamoto and Kyouki Toba, "Journal of the Japan Metals 7° Society," Vol. 14, No. 13, No. 2 ( 1
950), it was reported that a Fe-Co-Si alloy material containing Fe, Co, and St as main components exhibits good soft magnetic properties.

However, this Fe-Co-Si alloy material is extremely brittle and has poor practical use, and there are problems in using it as it is as a core material for a magnetic head.

[Problem that the invention seeks to solve]

The present invention aims to improve the above-mentioned problems, and has the magnetic properties, that is, the saturation magnetic flux density Bs is large, the coercive force 1c is small, the magnetostriction λS is almost zero, the magnetic anisotropy is small, and the mechanical properties, namely, The object of the present invention is to provide a soft magnetic thin film that has high hardness, excellent wear resistance, thermal stability and heat resistance, and chemical stability, that is, excellent corrosion resistance.

[Means for solving problems]

The present invention is based on the discovery that the above-mentioned problems can be improved without lowering the saturation magnetic flux density by adding nitrogen to a magnetic thin film containing Fe, Aj2, and Ge as main components. It is something.

However, according to the present invention, Pea AIbGec Nx
(However, a, b, c and
a S 84 1≦b<31 1≦C≦31 0.1≦x≦30 and a soft magnetic VIi-crotch with a composition such that a+ b+ C+x=too.

In the above composition, a portion of Aβ can be replaced with Ga and a portion of Ge can be replaced with Si. Also, a part of Fe can be replaced with Co or R.
At least one type of u can be substituted in an amount of 15 atomic % or more.

Further, the film thickness of the magnetic transfer property 1 according to the present invention having the above-mentioned composition is preferably 10 Å or more and 1 van or more, and more preferably 10 Å or more and 100 μm or less.

[Effect]

The soft magnetic S-crotch according to the present invention has a higher saturation magnetic flux density than the Sendust alloy, and because it contains N, the magnetic permeability is higher than that of Pe, -Aβ-Ge alloys that do not contain N.
As a result, the specific resistance was 1 (t), and the hardness and therefore the wear resistance were improved.

In the soft magnetic thin film according to the present invention, Fe, Aj! and the composition ratio for each element of Ge, namely a, b and C
Regarding the value of , if it is outside the range indicated in -1-, the magnetic properties will deteriorate such as the magnetization becomes larger, and regarding the composition ratio of N, that is, the value of X, this is outside the above range, that is, if X is 0.1
If X is less than 30 atomic %, the effects of N addition, such as specific resistance and hardness, will not be observed, and if X exceeds 30 atomic %, the magnetic permeability will be low -1. This may cause inconveniences such as

Furthermore, when a part of lie is replaced with Go in a series of compositions, it is possible to further improve the saturation magnetic flux density Bs and improve corrosion resistance. Even when replacing a part of e with Ru, even though Ru is non-magnetic, it does not impair the soft magnetic properties and hardly causes a low Bs of 1. I was able to improve my sexuality.

Embodiments] In the method for manufacturing a soft magnetic thin gland according to the present invention, 'C' is preferably a so-called vapor phase thin film production technique.

This is because, for example, it is difficult to uniformly introduce a large amount of nitrogen using a general melting method.

``In other words, energized nitrogen floats as slag during alloy melting.''
It is separated from the alloy as an hL impurity.

Therefore, the soft magnetic thin film according to the present invention is preferably produced by a vapor deposition method, an ion implantation method, or the like. Examples of vapor deposition methods include flash vapor deposition, in-gas vapor deposition, ion blasting, sputtering, cluster ion beam method, etc. Also, vapor deposition and ion implantation may be performed simultaneously. In addition, as a method of introducing nitrogen N into the magnetic thin film, +
1.1 A method in which vapor deposition or the like is performed in an atmosphere containing nitrogen gas, and the amount of nitrogen N in the magnetic layer is adjusted and introduced into the magnetic layer, which is affected by the concentration of nitrogen gas.

(2) A method of introducing nitrogen N into the resulting magnetic Wi film using a compound of nitrogen N and at least 14M of each component and an alloy of the remaining components as an evaporation source, etc. Can be mentioned. Furthermore, Fe constituting the magnetic thin film.

IN! To adjust the composition of each component such as (II Fe+i+Ge, other additives, substitution metals, etc.), weigh out the predetermined proportions, summarize them, and calculate, for example, i A method in which a ζ composite alloy ingot is formed by melting by single-frequency melting or the like, and this alloy ingot is used as an evaporation source. (3) A method of preparing evaporation sources for individual elements of each component and controlling the output (applied voltage) applied to these evaporation sources to control the evaporation speed and composition; (4) Examples include a method of implanting other elements while depositing an alloy as an evaporation source.

Example 1 Each metal of iron, aluminum, and germanium was weighed, melted in a vacuum using a high-frequency melting furnace, and poured into a mold to form an electrode coolant with a diameter of 50 m and a diameter of 111 m. Soto was created.

Using this target, sputtering was performed using a Brechy Magne Ron type sputtering apparatus according to the sputtering conditions described above.

Sputtering conditions RF power 1 (IOW
Distance between boards 1tilj 30 Dragon board temperature
~20'C (water cooling) ultimate vacuum level 3
X]]0-'''Torr gas pressure 5
X 10-' Torr thickness
Approximately 2.8 to 3.1 μm According to the above sputtering conditions,
Static gas was used as an inert gas, and N2 was added to the Ar gas to perform spasotering. Here, the amount of N2 mixed in is controlled by partial pressure, and sputtering is performed while changing the ratio of N2, so that fi
A thin section of e-^ρ-〇e alloy was formed. The obtained N-containing Fe-A#-Ge based alloy was heat treated at 550°C for 1 hour.

In Example 1, the film composition obtained when the N2 gas content j+-, and the magnetic coercive IC], MI
The results of measuring the magnetic permeability μIMHz at Iz and the corrosion resistance are shown in the drawing. To measure the corrosion resistance using a
It was immersed in the specified NaCl solution for 9 hours and the state of rust on the surface was visually observed.
Those marked with ○ maintain a mirror surface even after being immersed in water for an hour, those marked with ○ show clouding on the surface under the same conditions, and remain mirror-like after 48 hours in city water, and those marked with △ show that the film surface becomes cloudy after immersed in mountain water for 48 hours. The mark X indicates that a thin layer of red rust has formed on the film surface after immersion in city water for 48 hours.

For comparison, the measurement results for those that do not contain N are shown in the table of the same drawing as 4<sita.

The measurement of each composition was carried out using the inner gas diffusion (thermal conductivity) method for N, and for the others using EPM^ (Electric Pr
obe (formerly Cro Analsis).

As is clear from these measurement results, the N-containing magnetized P1 thin film according to the present invention improves magnetic permeability and corrosion resistance without increasing coercivity 1c compared to a soft magnetic thin film that does not contain N. Improvements are being made.

As mentioned above, in the soft magnetic thin film according to the present invention, by containing nitrogen N as a component, it is possible to achieve the same quotient + 3 magnetic coefficient and corrosion resistance, but it is also possible to achieve quotient hardness. The wear resistance is measured to be "-1", and no deterioration in magnetic properties such as saturation magnetic flux density and coercive force is observed. In particular, the inclusion of nitrogen N increases the specific resistance and reduces the eddy current loss in the commercial frequency region, which improves the frequency characteristics of magnetic permeability. It is extremely useful for magnetic heads used in

Although the details of the role of nitrogen N in this magnetic thin film are unknown, since the hardness is significantly improved, it is expected that quotient hardness particles such as Fe nitride may be generated.

Furthermore, in the soft magnetic thin film according to the present invention described above, various elements may be added as additives in order to further improve corrosion resistance, wear resistance, and other various properties.

Elements used as this additive include TLZr,
Na group redundant elements such as llf, V, Nb, V such as Ta
Group a elements, Via group elements such as Cr, Mo, and W, Mn
and the like, and further platinum group elements include 5th period platinum group elements, namely Rh, Rd, and 6th period platinum group elements, namely Os, Ir, Pt, etc. One type or a combination of two or more of these additives may be added to the magnetic thin film in an amount of θ to 10% by weight.

In addition, if present, oxygen can be contained together with nitrogen and N.

〔Effect of the invention〕

As mentioned above, the soft magnetic thin film according to the present invention has a high commercial permeability without decreasing the saturation magnetic flux density or increasing the coercive force, has excellent corrosion resistance, and has excellent wear resistance of commercial hardness. (Furthermore, since it is possible to obtain a soft magnetic thin film with excellent heat resistance and no thermal instability like an amorphous magnetic thin film, it can be used as a thin film magnetic core of a thin film magnetic head for areal density recording, for example. The profits are extremely large.

[Brief explanation of drawings]

The figure is a table showing the composition of the soft magnetic thin film and the measurement results of capacitance 11I. −′

Claims (1)

[Claims] It is represented by the composition formula Fe_aAl_bGe_cN_x (where a, b, c, and x represent their respective composition ratios as atomic %), and each composition range is 55≦a≦84 1≦b≦ 31 A soft magnetic thin film characterized in that 1≦c≦31 0.1≦x≦30 and a+b+c+x=100.