JPS63177404A - Laminated amorphous magnetic film and magnetic head using the same - Google Patents

Abstract

PURPOSE:To obtain an amorphous alloy film having high saturated magnetic flux density, excellent thermal stability and approximately zero of magnetostrictive constant by setting the crystallizing temperature of a first amorphous film higher than that of a second amorphous film in a composite amorphous film which has the first amorphous film as a base film and the second amorphous film as a main magnetic film. CONSTITUTION:In a laminated amorphous film which has a first amorphous film as a base film 2 and a second amorphous film as a main magnetic film 3, the crystallizing temperature Tx1 of the film 2 is larger than that Tx2 of the film 3. The film 3 may be of an Fe amorphous film or a Co amorphous film, but the Co amorphous film causes a larger effect. The film 2 may be of a ferromagnetic film containing different element from that of a nonmagnetic film or the film 3. However, it is desired to compose the films 2, 3 of the same elements in view of the bondability of the film 2 to the film 3 and the chemical stability thereof. The thickness of the film 2 is suitably 30-500Angstrom .

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a magnetic film used in a magnetic head pole suitable for high-density magnetic recording, particularly a high saturation magnetic flux density.

The present invention relates to a laminated amorphous magnetic film having characteristics of high crystallization temperature and low magnetostriction constant, and a magnetic head using the same.

[Conventional technology]

In recent years, there has been remarkable progress in increasing the density and performance of magnetic recording.
In the field of TR, high coercive force tapes are being used to improve recording density, and in order to sufficiently record and reproduce signals, there is a need for magnetic heads that use high-performance magnetic materials with high saturation magnetic flux density. is increasing. In addition, in thin film heads used for computer disks, as recording density increases, it is necessary to make the magnetic pole thinner to improve resolution, and magnetic saturation easily occurs at the thin magnetic pole tip. For this reason, a thin film magnetic head using a magnetic film with a high saturation magnetic flux density is required. Furthermore, even in single-pole heads for perpendicular magnetic recording, which have been actively researched in recent years, it is necessary to make the main pole extremely thin in order to improve recording density. To solve this problem, a single-pole head for perpendicular magnetic recording using a high-performance magnetic film with high saturation magnetic flux density is required.

Conventionally, N1- was mainly used as a magnetic film for these magnetic heads.
PE-based alloy films (permalloy films) have been used, but in recent years, amorphous alloy Svantha films have been developed as high-performance magnetic films with high saturation magnetic flux density. Among these, vitrification elements are mainly 7. Compared to amorphous alloys whose vitrification elements are metalloid elements such as B, Si, and P, amorphous alloys made of R have superior heat resistance and corrosion resistance, and are used as magnetic films for magnetic heads. It has excellent properties. Zr
Specifically, the amorphous alloy is represented by the composition formula of MaTbZr. Here M is Co with magnetic moment, F
T is at least one of e, Ni, etc., and T is a transition metal element other than M and Zr. Such vitrification elements are mainly 7. Regarding the amorphous alloy consisting of
Specification No. 5-138049 and JP-A-56-844
It is stated in the specification of No. 39 etc. Among these Zr-based amorphous alloys, the co-zr-based amorphous alloy in which M is Co has a high saturation magnetic flux density and is an excellent magnetic material. However, the magnetostriction constant of this amorphous alloy is 2~4X1
Since V exhibits a relatively large value of 0-', as an additive element T, V makes a negative contribution to the magnetostriction constant of the amorphous alloy.

By using elements such as Nb, Ta, Cr, Mo, and W, an amorphous alloy with a magnetostriction constant of approximately zero can be obtained. However, these elements have a lower ability to form an amorphous state than tZr, so when they are substituted with Zr in a Co-7,r-based amorphous alloy, the crystallization temperature decreases and the crystallization becomes amorphous. Boundary is low C
There is a problem in that the maximum saturation magnetic flux density obtained in the amorphous state decreases as the magnetic flux density shifts to o@ degrees.

[Problem that the invention seeks to solve]

An object of the present invention is to solve such problems and to obtain an amorphous alloy film having a high saturation magnetic flux density, excellent thermal stability, and a magnetostriction constant of approximately zero, and a magnetic head using the same.

[Means for solving problems]

The above object is achieved by forming a laminated amorphous magnetic film having the following configuration. That is, as shown in FIG. 1, in a laminated amorphous film in which the first amorphous film on the substrate 1 is the base film 2 and the second amorphous film is the main magnetic film 3, the first It is assumed that the crystallization temperature TXI of the second amorphous film 2 is higher than the crystallization temperature TX2 of the second amorphous film 3.

The second amorphous film 3 may be either an Fe-based amorphous film or a Co-based amorphous film, but the Co-based amorphous film is more effective.

Further, the first amorphous film 2 may be a nonmagnetic film or a ferromagnetic film containing a different element from the second amorphous film 3. However, from the viewpoint of adhesion between the first amorphous film 3 and the second amorphous film 3 and chemical stability, the first and second amorphous films are composed of the same element. This is desirable.

Further, the thickness of the first amorphous film is not less than 30 Å. However, the first amorphous film is either nonmagnetic or a ferromagnetic material that generally has a lower saturation magnetic flux density than the second amorphous film. Therefore, if the thickness of the first amorphous film is increased, the total magnetic flux density of the laminated amorphous film becomes smaller, so the appropriate thickness of the first amorphous film is 30 to 500. be.

[Effect]

Here, it is thought that the amorphous film provided as the base acts to promote the amorphization of the film formed thereon. As a result, it is thought that even a film that would be crystallized if nothing is provided on the base can be made amorphous. Therefore, in the case of a Co-based amorphous alloy.

By providing an amorphous base, the amorphous region can be expanded to the high Co concentration side, and the maximum saturation magnetic flux density obtained in the amorphous state is increased. In addition, a magnetic head that uses this laminated amorphous magnetic film with high saturation magnetic flux density in its magnetic core,
It has excellent recording characteristics because it can generate a large magnetic field at the tip of the magnetic core.

〔Example〕

Hereinafter, the present invention will be explained in detail with reference to Examples.

Figure 2 shows a 1 μm thick C0-Ta-
CoTa Z r when forming 'l, r-based amorphous film
A characteristic diagram of the system alloy film is shown. A C0TaZr-based amorphous film was produced on a 7059 (trade name, Corning, Inc., USA) glass substrate using a high-frequency bipolar sputtering device.

Co-'i'a-7. Whether or not the r film was in an amorphous state was confirmed by the X-ray diffraction pattern, resistivity, and coercive force.

In other words, there is a peak in the X-ray diffraction pattern, and when the resistivity is 0.3μΩm or more and the coercive force is 10e or less, the C0
It was assumed that the TaZr film was in an amorphous state. The amorphous region is
Co-'pa system with Co composition up to 95 at%, Co-2
The Co composition is up to 94 at% in the r system.

As the Zr composition increases, the Co concentration increases. Magnetostriction is determined approximately by the ratio of Ta and zr compositions*
When T a : Z r "5 : 3, it becomes O. The saturation magnetic flux density Bs is determined by the Co composition, and the higher the Co composition, the higher the saturation magnetic flux density B8 can be obtained. Magnetostriction is desirable as a head material. is O, the maximum saturation magnetic flux density B8 obtained in the amorphous state is 1.4'
It is l'.

In Figure 3, C05sTaaZr7 (at
%) of amorphous alloy "f: After forming a film thickness of 30, eoT
Co'f when aZr-based amorphous sweet gold is formed into a film with a thickness of μm
a7. A characteristic diagram of an r-based alloy film is shown. The composition dependence of magnetostriction and saturation magnetic flux density Bs is the same as when no underlying amorphous film is provided, but the amorphous region expands by 9 on the high Co concentration side 1.
, the maximum saturation magnetic flux density Bs obtained in an amorphous state with magnetostriction of 0 was 1.6T. This is 0.2 T stronger than when no base film is provided. Furthermore, when comparing the crystallization temperature for the same composition, the crystallization temperature was 20C higher when the base amorphous film was provided, and the thermal stability was superior.

FIG. 4 shows that in a CoTaZr alloy film with magnetostriction of 0,
It shows the relationship between the maximum saturation magnetic flux density obtained in an amorphous state (hereinafter referred to as maximum saturation magnetic flux density) and the thickness of the underlying amorphous film. The composition of the underlying amorphous film is Co g5 Ta
s Zr7 (at%), crystallization temperature is 550C
The % saturation magnetic flux density Bs is IT. The maximum saturation magnetic flux density increases as the thickness of the underlying film increases;
Above Å, saturation occurs.

FIG. 5 shows that in a C0TaZr alloy film with magnetostriction of 0,
The relationship between the maximum saturation magnetic flux density obtained in an amorphous state and the crystallization temperature Tx of the underlying amorphous film is shown. The thickness of the underlying amorphous film is 30A. The higher the crystallization temperature of the base amorphous film, the higher the maximum saturation magnetic flux density, but when the crystallization temperature of the base amorphous film becomes 550C or higher, it becomes saturated.

Table 1 shows the results when the magnetostriction of the main magnetic film is zero when the combination V of the first amorphous film (base film) and the second amorphous film (main magnetic film) is varied. , shows the maximum saturation magnetic flux density obtained in the amorphous state and the increase in crystallization temperature due to the provision of an underlayer. Each film was produced on a 7059 (trade name, Corning, Inc., USA) glass substrate using a high-frequency two-pole sputtering device. The thickness of the base film was 30, and the thickness of the main magnetic film was 1 μm. In either combination, the provision of the underlayer increases the maximum saturation magnetic flux density obtained in the amorphous state, increases the crystallization temperature, and improves thermal stability. Further, when the underlying film and the main magnetic film have the same constituent elements, the increase in saturation magnetic flux density and crystallization temperature due to providing the underlying film is greater.

Next, Co55T with a film thickness of 30 mm was used as the underlying amorphous film.
a s Zr s (a t %) A for amorphous 5Kk,
Co g2 'f'a of Bg=1.5T as main magnetic film
5. A thin film magnetic head having the cross-sectional structure shown in FIG. 6 and having a laminated amorphous magnetic film using a Zr3 alloy film as a magnetic pole was fabricated by a known thin film forming technique. This thin film head is
Atz Os T iC, Atz Os or Z
A non-magnetic substrate 1 made of R02, etc., a lower magnetic pole 4 made of a laminated amorphous magnetic film, a gap layer 5 made of Atz03.5iOz, etc., a conductor coil 8 made of Cu, Ate, etc., an insulation made of polyimide resin, 5iOz, etc. It is composed of a layer 6 and an upper magnetic pole 7 made of a laminated amorphous film.

A thin film magnetic head having the structure shown in FIG. 6 and a thin film magnetic head without an underlayer were manufactured, and the reproduction output was examined. The reproduction output of the thin film magnetic head with the underlayer was about 10 times greater than that without the underlayer. This is considered to be due to the following reasons. In other words, when the saturation magnetic flux density of the main magnetic film is 1.5T, the main magnetic film with a base is in an amorphous state and has excellent soft magnetic properties, whereas the main magnetic film without a base is in a crystalline state. This is because the soft magnetic properties are extremely poor.

〔Effect of the invention〕

According to the present invention, an amorphous alloy film having a high saturation magnetic flux density, a high crystallization temperature, excellent thermal stability, and a magnetostriction constant of almost zero can be obtained. A magnetic head with a magnetic pole with excellent soft magnetic properties can be obtained.

[Brief explanation of the drawing]

Figure 1 is a cross-sectional view of the laminated amorphous magnetic film of the present invention. Figure 2 is a characteristic diagram of the Co'razr alloy film without an amorphous base film. Figure 3 is a cross-sectional view of the amorphous base film. C0T when providing
The characteristic diagram of the aZr alloy film, FIG. 4, is co'fa7. Figure 5 is a diagram showing the relationship between the thickness of the underlying amorphous film and the maximum saturation magnetic flux density obtained in the amorphous state in the r-based alloy film.
A diagram showing the relationship between the degree of crystallization of the base amorphous film and the maximum saturation magnetic flux density obtained in the amorphous state in a 0TaZr alloy film, FIG. 6 shows the laminated amorphous magnetic film of the invention. FIG. 2 is a cross-sectional view showing a thin film magnetic head using a magnetic pole as a magnetic pole. 'f, r O Z 6 Fig. 71L Tachibana Kadamoto No. 4 Fig. O20dθ 6θ 3θ Non-5L ¥25 All I) Fresh moga 1 Ursu 4 (A) No. 5
figure

Claims (1)

[Claims] 1. In a composite amorphous film in which the first amorphous film is the base film and the second amorphous film is the main magnetic film, crystallization of the first amorphous film The temperature T_x_1 is the crystallization temperature T of the second amorphous film
A laminated amorphous magnetic film characterized in that the film is larger than _x_2. 2. The laminated amorphous magnetic film according to claim 1, wherein the second amorphous film is a film containing Co as a main component. 3. The main components of the first amorphous film and the second amorphous film are
3. The laminated amorphous magnetic film according to claim 1, wherein the laminated amorphous magnetic film is composed of the same element. 4. The laminated amorphous magnetic film according to any one of claims 1 to 3, wherein the first amorphous film has a thickness of 30 Å or more and 500 Å or less. 5. The laminated amorphous magnetic film according to any one of claims 1 to 4, wherein the first amorphous film has a crystallization temperature of 550° C. or higher. 6. In a magnetic head using a composite amorphous film in which the first amorphous film is the base film and the second amorphous film is the main magnetic film, the crystallization temperature of the first amorphous film A magnetic head using a laminated amorphous magnetic film, characterized in that T_x_1 is higher than the crystallization temperature T_x_2 of the second amorphous film.