JPS60218821A - Manufacture of fe-al-si system alloy thin film - Google Patents

Abstract

PURPOSE:To obtain Fe-Al-Si system alloy thin film having excellent magnetic characteristic and high hardness by executing the sputtering in inactive gas including O2. CONSTITUTION:An Fe-Al-Si system alloy thin film is formed on a crystallized glass substrate by using Ar gas as inactive gas and executing the sputtering by the magetron sputtering method through mixture of O2 into such Ar gas. With increase of the rate of O2 included in the Ar gas, the Fe-Al-Si system alloy thin film obtained is superior not only in hardness and durability for rust, etc. but also in magnetic characteristic such as permeability and saturated magnetic flux density, etc.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for producing Fe-A L-S L alloy thin films, and more specifically to a method for producing Fe-A L-S L alloy thin films.
This paper relates to improvements in the sputter method for producing 8A series 1 alloy thin films.

[Background technology and its problems]

For example, in magnetic recording and reproducing devices such as VTRs (video tape recorders), the recording signal density and frequency are increasing, and in response to this higher density recording, magnetic powder is being used as a magnetic recording medium. Fe.

So-called metal tapes using ferromagnetic metal powder such as C() HNA, and so-called vapor deposition tapes in which ferromagnetic metal materials are deposited on a base film by vapor deposition, have come into use. Since this type of magnetic recording medium has a high residual magnetic flux density Bre, the head material of the magnetic head used for recording and reproduction is also required to have a high saturation magnetic flux density of 8 g.

For example, the saturation magnetic flux density BS of the 7-elite material, which has been widely used as a magnetic head material, is low, and the wear resistance of permalloy is problematic.

On the other hand, along with the above-mentioned high-density recording, the trunk width of the recording track recorded on the magnetic recording medium is also becoming narrower, and correspondingly, the track width of the magnetic head is also becoming extremely narrow. requested.

Conventionally, so-called composite magnetic heads have been developed in which a magnetic alloy thin film serving as a magnetic core is deposited on a non-magnetic substrate such as ceramics, and the track width is the thickness of this magnetic alloy thin film, and insulating magnetic alloy thin films and conductive thin films. A thin film magnetic head with a multi-layered structure using a body thin film has been proposed, and magnetic alloy thin films such as Fe, AJ, and SL are used in this type of magnetic head.
Sendust alloy thin film, which is a Fe-AJ-8A alloy mainly composed of , is attracting attention.

This Sendust alloy thin film has a high saturation magnetic flux density B8 and relatively high hardness, so it can be applied to magnetic recording media with a high residual magnetic flux density such as the metal tape mentioned above. .

However, although the sendust alloy thin film has relatively high hardness, it has disadvantages such as inferior wear resistance compared to ferrite materials and the like, and since it is a metal material, it is easily rusted.

Therefore, the main component of the sendust alloy thin film is Fe.
In addition to 5At+Sh, for example, TA y Cr rNb,
It is being considered that additives such as platinum group elements are added to improve wear resistance by reducing hardness and preventing the occurrence of the above-mentioned edges.

However, it has been found that when the above additive is added, the saturation magnetic flux density B of the sendust alloy thin film decreases.

According to experiments conducted by the present inventors, the degree of addition of additives is B,
A decrease in Br is extremely disadvantageous when dealing with a magnetic recording medium having a high residual magnetic flux density Br such as a metal tape.

Furthermore, when a metal material like the Sendust alloy thin film mentioned above is used as the core of a magnetic head, a decrease in magnetic permeability in the high frequency range due to so-called eddy current loss becomes a problem. There is a risk that sufficient playback output may not be obtained.

Therefore, conventionally, it has been considered to use an amorphous magnetic alloy material (so-called amorphous magnetic alloy material) which has a high saturation magnetic flux density Bsk with little decrease in magnetic permeability in a high frequency region in place of the Sendust alloy thin film described above. However, this amorphous magnetic alloy material is thermally unstable, and long-term heating or thermal cycling will greatly deteriorate its magnetic permeability and reduce regeneration efficiency, and there is a particularly high possibility of crystallization. So 50
Temperatures above 0°C cannot be applied for long periods of time.

Therefore, it is not preferable to use the amorphous magnetic alloy material in a magnetic head that requires processing at a temperature of 500° C. or higher, such as glass fusing, in the manufacturing process.

[Means for solving problems]

Therefore, the present inventors conducted intensive research to improve the magnetic properties and hardness of a thermally stable Fe-Aj-8b alloy thin film, and found that 0. We have come to the knowledge that the Fe-AA-8L alloy thin film obtained by sputtering in an inert gas containing gas has high magnetic permeability and high hardness without reducing the saturation magnetic flux density. Ta.

The present invention has been made based on this knowledge, and is characterized in that sputtering is performed using an inert gas containing O2.

The above-mentioned sputtering method may be any method as long as it is normally performed, such as bipolar direct current sputtering, triode sputtering, quadrupole sputtering, magnetron sputtering, high frequency sputtering, bias sputtering, asymmetric sputtering, etc. Examples include AC sputtering, facing target sputtering, and ion sputtering.

In the present invention, the atmosphere in which the sputtering is performed is important. That is, sputtering is normally performed in an inert gas, but in the present invention, sputtering is performed in an inert gas containing O2.

As the inert scum, He HN6, Ar, etc. can be used, and among them, it is preferable to use Ar. 0 in these inert gases! Mix 0.01 to 40 volumes of. Above 0. If the content is less than 40% by volume, sufficient effects cannot be expected, and if the content is less than 40%
If it exceeds the body volume, there is a risk that the magnetic permeability etc. will decrease. Furthermore, the inert gas may contain N instead of the above 02 bakashi.

Furthermore, the gas pressure during the sputtering is lXi O
It is preferable that the gas pressure is in the range of 2.0 to 2.0
If it exceeds rr, the sputtering speed will become slow.

On the other hand, pe-At-s formed by the above sputtering
The composition range of the b-based alloy thin film is preferably AJI of 2 to 10% by weight, SL of 3 to 16% by weight, and the balance Fe, preferably A14 to 8% by weight.
"' 11% by weight, the balance being Fe. Also, the thickness of the obtained Fe-AA-8l-based alloy thin film was 100% by weight.
It is preferable that the thickness is within the range of λ to 50μ.

It is also possible to replace a part of the Fet with at least one of Co8 and NL.

The saturation magnetic flux density BS can be increased by replacing a portion of the Fe with Co. In particular, 40% by weight of Fe
The maximum saturation magnetic flux density BB can be obtained by substituting CO with CO. The amount of Co substitution is θ~6 with respect to Fe.
It is preferable that the content is within the range of 0% by weight.

On the other hand, by replacing a portion of the Fe with NL, the magnetic permeability can be maintained at a high level without reducing the saturation magnetic flux density BB. The amount of substitution of this NL is FeK
It is preferable that the amount is within the range of 0 to 40% by weight.

Furthermore, various elements may be added as additives to the Fe-Aj-8L alloy thin film described above. Elements used as the above additives include nIa group elements such as Y, 'rb,
■A group elements such as ZrtHr, Va group elements such as Nb tT&, Ma group elements such as Cr, MO, W, Mn, T
■A group elements such as c, Re, etc., Ru l Rh jP d
Platinum group elements such as HOs p I ry P , Ga
, Ilb group elements such as In, G6. Group IVb elements such as Sn, Sb.

Examples include Vb group elements such as Bb, and lanthanum series elements such as La, Co, and Na+Ga. These additives are F e
-A1-SL It is added in a range of 0 to 10% by weight to the L-based alloy. If the amount of the additive exceeds 10% by weight, the magnetic properties of the resulting thin film will deteriorate.

By the way, various methods can be considered to adjust the composition range of the obtained Fe-Aj-8A alloy thin film, for example, α) a method of using an alloy ingot having a predetermined composition as a target, (2) Examples include a method in which targets for each component are prepared and the composition is controlled by the number of these targets, and (3) a method in which targets for each component are prepared and the composition is adjusted by controlling the output applied to these targets.

In the method α) above, Fe1*AA+sL and other additives,
Substitute metals and the like are weighed out to a predetermined ratio, and then agglomerated and melted in, for example, a high-frequency melting furnace to form an alloy ingot, and this alloy ingot is used as a target during sputtering.

The above method G) uses Fe, A1. , SL targets are prepared respectively, and the composition of the thin film obtained is controlled by increasing or decreasing the number of these targets during sputtering. For example, a large disk-shaped Fe target is prepared, and a small AA plate and an Sb plate C are arranged on the Fe metal target. The composition is then controlled by increasing or decreasing the number of the AA plates or NL plates.

In this case, Aj meta-
A small Fe plate and a SA plate may be arranged on this AA target, or an S ditarget may be prepared as a large disc-shaped target, and this S = F on the metal target,
Boards and AA boards may be placed side by side. Further, as the large disc-shaped target, an Fe-A1 alloy target (6) or Fe-Sir alloy target having a predetermined composition,
It is also possible to prepare L-8↓ alloy targets and arrange NL plates, AL plates, and Fe plates on these alloy targets.

In the method (3) above, Fe, Sb, and Fe targets are prepared, a voltage is applied to each of these targets, and the composition of the resulting alloy thin film is controlled by controlling this voltage. It comes out.

In this case, it is preferable to perform sputtering while rotating the substrate on which the alloy thin film is to be deposited, so as to uniformize the composition of the alloy thin film deposited on the substrate.

As mentioned above, by performing sputtering in an inert scum containing 02, it has excellent magnetic properties and high hardness. That is, according to the experiments of the present inventors, F e -A j obtained by sputtering in an inert gas containing F e -A j
! It has been found that the thin S= alloy thin film can obtain high magnetic permeability without reducing the saturation magnetic flux density BS, and also has a small coercive force Hc. For example, it has been found that the magnetic permeability at IMHz is approximately twice as high as that of a material sputtered in a normal inert gas. Additionally, an increase in specific electrical resistance was observed, and it was found that deterioration of magnetic permeability was suppressed, especially in the high frequency range.

Furthermore, it was also found that the hardness of the Fe-A-A-SL alloy thin film obtained by sputtering in an inert gas containing 02 was significantly improved, and it was also extremely rust-resistant.

By the way, regarding the role played by 0□ in the present invention,
The details are unknown, but the above 02 is Fe-AA-84
These Fe penetrate into the alloy thin film.

It is presumed that it contributes in some way, such as by forming oxides of AA and SL.

Hereinafter, specific examples of the present invention will be described, but it goes without saying that the present invention is not limited to these examples.

〔Example〕

Example 1 SA with purity 99.9999%Af with purity 99.99%
Using Fe with a purity of 99.99% as a raw material, each of these raw materials was weighed and separated, melted in a vacuum using a high frequency melting furnace, and poured into a mold and formed into a diameter of 50 mm.
An electrode target with a thickness of 1 mm was prepared. The composition of this target was Fe8□AA7S=.

Using the above target, sputtering was performed by magnetron sputtering according to the following long batter conditions.

Spactor conditions RF power: 7-800W Target-to-substrate distance: 30mm Substrate temperature: ~20℃ [water cooling] Ultimate vacuum: 3 x 10""' Torr gas pressure
4 X l O-" Torr film thickness: approximately 6 μm According to the above sputtering conditions, using Ar gas as an inert gas, sputtering was performed by mixing 02 into the Ar gas. Here, the amount of 02 mixed above was determined by partial pressure. A Fe-A1.-SL alloy film was formed on a crystallized glass substrate by sputtering while controlling and changing the ratio of 02.The resulting Fe-AJ-8JJ alloy thin film was
After heat treatment at ℃ for 1 hour, hardness, specific electrical resistance, magnetic permeability, and saturation magnetic flux density were measured.

FIG. 1 shows the proportion of 02 contained in Ar gas and the obtained Fe-A1. - It is a characteristic diagram showing the relationship between the hardness of the SL alloy thin film. The hardness here was measured as Vickers hardness, and was measured by molding at a weight of 50F for 15 seconds.

It can be seen from FIG. 1 that as the proportion of 02 contained in the Ar gas increases, the hardness of the obtained F6-AA-8h alloy increases significantly.

For example, 0. The hardness of the Fe-AJ-8A alloy thin film obtained by sputtering in Ar gas containing no O2E15 volume is 630, whereas the hardness of the Fe-AJ-8A alloy thin film obtained by sputtering in Ar gas containing no O2E15 volume is Hv=630. Rel F
e -A A -S Hardness of L-based alloy thin film Hv=io
I met with oo.

Next, FIG. 2 is a characteristic diagram showing the relationship between the proportion of o2 contained in Ar gas and the electrical resistance (specific resistance) of the obtained Fe-AJI-8A alloy thin film. The above electric resistance was measured by a four-probe method, and F a -A A -S L obtained by sputtering in Ar gas not containing o.
This is the specific resistance when the electrical resistance of the alloy thin film is 1.0, and the value is corrected for the film thickness.

This specific resistance is an important element in estimating the magnetic permeability in the high frequency region of the obtained Fe-AJL-8= series alloy thin film. That is, in general, a concentric induced current (eddy current) flows in a magnetic body in response to a temporally changing magnetic flux, and this eddy current consumes electricity, causing so-called eddy current loss. This eddy current loss is greatly related to the frequency and the resistivity of the magnetic material, and causes a decrease in magnetic permeability, especially in a high frequency region.

For example, the resistivity of normal Sendust alloy material is 85μΩ-
It is known that the magnetic permeability in the high frequency region tends to be low because the resistivity of the amorphous alloy material is smaller than 150 μΩ.

Therefore, the resistivity of the resulting Fe-J,-8L alloy thin film is preferably as high as possible. Here, in Figure 2, 47A
It can be seen that as the proportion of 02 contained in the r gas increases, the specific resistance of the obtained F6-AJ-SL alloy thin film increases linearly. For this reason, 02
It is estimated that the Fe-AJ-SL alloy thin film obtained by sputtering in an inert gas containing Fe-AJ-SL is advantageous in terms of magnetic permeability in a high frequency region.

FIG. 3 is a characteristic diagram showing the relationship between the 020 ratio contained in Ar gas and the magnetic permeability at IMHz of the obtained Fe-A-A-SL alloy thin film. Note that the magnetic permeability was measured using a permeance meter.

It can be seen from FIG. 3 that as the 0□0 ratio in the Ar gas increases, the magnetic permeability of the obtained Fe-AA-8L alloy thin film increases significantly. For example 0
When 20 ratio is 71 volume ratio, magnetic permeability is approximately 2
．． It can be seen that the number has reached 5 times.

The frequency characteristics of magnetic permeability of thin films are shown. In addition, in this Figure 4, the curve a has a 020 ratio of 0 volume, and the curve a has a 020 ratio.
The proportion of 02 is 2 volumes, the curve C is 5 volumes, the curve d is 10 volumes, and the curve e is 0. The curve f shows the case where the ratio of 0□0 is 15 volume chi, and the curve f shows the case where the 0□0 ratio is 20 volume chi.

As shown in Fig. 4, the F e -A L -S L alloy thin film obtained by sputtering in Ar gas containing 02 has a higher density than that obtained by sputtering in Ar gas not containing 02. It can be seen that relatively high magnetic permeability can be obtained at any frequency. In particular, as the ratio of 02 increases, the decrease in permeability at high frequencies decreases, and the permeability is low, but 20-30
It is considered to have sufficient practicality in the MHz frequency range.

FIG. 5 is a characteristic diagram showing the relationship between the proportion of 02 contained in Ar gas and the saturation magnetic flux density of the obtained Fe-AA-8= alloy thin film.

What should be noted in Fig. 5 is that 0
The saturation magnetic flux density of the Fe-AJL-8L alloy thin film obtained by introducing No. 2 was improved.

This is extremely useful compared to the case where, when additives are added to improve the temperature characteristics of hardness, magnetic permeability, etc., the saturation magnetic flux density generally decreases. In this example, the decrease in saturation magnetic flux density may have been suppressed, or rather the saturation magnetic flux density may have been improved.

As is clear from the above measurement results, A containing 0□
Fe-AJ obtained by sputtering in r gas
-8L alloy thin films are not only excellent in terms of durability such as hardness and rust, but also excellent in magnetic properties such as magnetic permeability and saturation magnetic flux density, and are used for example in magnetic heads. It is suitable for application.

Example 2 AJ on a pure iron target as a target.

Composite target with S= on it is FeazAA7S
Using a composite target in which Fe, AA, and SLe are placed on the target of L, , the above At, Si, h or F
Change the number of e, 8t, Si, and include 02 of io volume chi.
Sputtering was performed in r Ar gas and Ar gas not containing Otk, and F e -A A of various compositions was performed.
A -8L alloy thin film (about 5 μm thick) was produced.

The magnetic permeability and hardness of the obtained Fe-Al1-8L alloy thin film were measured. The magnetic permeability was measured using a permeance meter, and the Vickers hardness was measured under a load of 50 f. Furthermore, the obtained F e -A A
The composition of the -Sb alloy thin film was analyzed using an X-ray microanalyzer for Fe, AJ, and SJJ. Here, the composition sputtered in Ar gas containing 02 was considered to have the same composition as that sputtered in Ar gas. The results are shown in Table 1.

1. A characteristic diagram showing the relationship between surface density and 2. Figure 2 shows the relationship between the ratio of Oo contained in Ar gas and the specific resistance of the resulting Fe-AJ, -8A alloy thin film (sputtering in Ar gas without 02). Fig. 3 is a characteristic diagram showing the relationship between the resistivity of the F e -A L-S L alloy thin film obtained by Ar
Proportion of O3 contained in gas and obtained F e −A
A characteristic diagram showing the relationship between the magnetic permeability of the A-S i= series alloy thin film at IMH2K. Figure 4 shows the magnetic permeability of the Fe-AJ-8A series alloy thin film obtained by sputtering in Ar gas containing 02. Characteristic diagram showing frequency characteristics, Figure 5 is Ar
Proportion of 02 contained in gas and obtained F e -A
This is a characteristic diagram showing the relationship between saturation magnetic flux density of A-SLL alloy thin film.

Patent Applicant Sony Corporation Agent Patent Attorney Kodo Koike 1) Toshiei - 05IU I'l) IIJ o, t4fi phantom → Continued from page 1 [Phase] Inventor Tatsuo Kumura Tokyo Parts Industry Ward Kitashinyo 6 No. 5-6 Sony Magne Products Co., Ltd. Internal procedural amendment (spontaneous) October 8, 1980 Manabu Shiga, Commissioner of the Patent Office 1, Indication of the case 1982 Patent application No. 75370 2, Name of the invention Fe- Manufacturing method for Al-Si alloy thin film 3, relationship with the amendment case
1B) Sony Co., Ltd. (Name) Representative Norio Ohga 4, Agent address 11, 2-6-4 Toranomon, Minato-ku, Tokyo 105
Mori Building 11th floor (50B) 8288 ■ Voluntary action 6. “Detailed description of the invention column” of the specification to be amended 7. Contents of the amendment (7-1) “Residual The description "magnetic flux density Br" is corrected to "coercive force HCJ".

(7-2) In the 1st θ line of the second page of the specification, the description "recorded track to be recorded" is corrected to "recorded magnetic pattern".

(7-3) The statement "extremely" on the 9th line of the 4th page of the specification is deleted.

(7-4) On page 7, line 6 of the specification, [Si weighs 3 to 16]
A certain statement has been corrected to "Si content is 3 to 16% by weight."

(7-5) The statement "The above-mentioned.

“The elements used as the above additives include Sc,
Ha group elements including lanthanum series elements such as Y, La, Ce, Nd, and Gd; IVaVa group elements such as Ti, Zr, If, etc.

Va group elements such as Nb and Ta, Via group elements such as Cr, No, and W, ■a group elements such as Mn, Tc, and Re, R
u, Rh, Pd, Os, It, Pt
Platinum group elements such as Ga, In, etc., Group B elements such as Ge, S
Examples include IVb group elements such as n, Vb group elements such as sb, etc. ” (7-6) Change the 7th line of page 9 of the specification and the description “output” to “
Correct as "power output".

(7-7) The statement "r800W" on line 19 of page 12 of the specification is corrected to rloOWJ.

(7-8) From the 14th line of page 14 of the specification (F) to the 15th line of the same page, the statement ``As a specific resistance, QΦ is f direct.'' has been changed to ``It is expressed as a specific resistance. ” is corrected.

(that's all)

Claims (1)

[Claims] A method for producing an Fe-AJ-8= alloy thin film, the method comprising performing sputtering in an inert gas containing Fe-AJ-8=02.