JPH011108A - magnetic head - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a magnetic head. More specifically, the present invention relates to a composite magnetic head that combines a core made of a nonmagnetic material and a thin ferromagnetic metal film.

(Prior Art) With the recent increase in the density of magnetic recording, magnetic tapes with higher residual magnetic flux densities Br are being used, and in order to cope with this, magnetic heads with high magnetic flux densities and narrow track widths are required. ing.

Conventionally, such magnetic heads are made by forming thin films of ferromagnetic metal such as Sendust alloy on a core/substrate made of ferromagnetic oxide using vacuum thin film forming technology, and forming gaps between the thin films of ferromagnetic metal. Composite magnetic heads are known.

A conventional composite magnetic head is shown in FIGS. 15 to 20.
The magnetic head in FIG. 15 has a magnetic gap g of approximately 4
A metal magnetic IM is formed on the thin film forming surface of the oxide magnetic material F tilted by 5 degrees, and a non-magnetic material N is filled on both sides of the magnetic gap g.

In the magnetic head shown in FIG. 16, a metal magnetic film M is formed in an A shape on both thin film forming surfaces of an oxide magnetic material F that is inclined in a substantially mountain shape with respect to a magnetic gap g, and these are butted to form a non-magnetic material N. It is joined by

In the magnetic head of FIG. 17, as shown in FIG. 18, a multilayer metal magnetic film M1 is formed on a substrate B1 made of an oxide magnetic material F1 and a non-magnetic material N1. A sandwich-structure head half was obtained by combining the two heads, and then the head half was butted and joined with another head half obtained in the same manner.

In addition, metal magnetic v as shown in FIG. 19 or 20
There are also heads with M curved or bent.

These conventional composite magnetic heads tend to have a wider band of magnetic flux flowing into the head due to higher recording density, and problems such as eddy current loss occurring in the metal magnetic film cannot be ignored. For this reason, the metal film part of the above-mentioned composite head tends to have a multilayer structure with a metal magnetic film of about 5 to 6 μm thick per layer, but at the same time consideration must be given to reducing the magnetic resistance of the entire film. becomes.

(Problems to be Solved by the Invention) However, in the case of the heads shown in FIGS. 15 and 16,
Metal magnetism [M] cannot be made large, so when used in a high frequency range, the magnetic resistance is relatively large, making it difficult for magnetic flux to pass through.

Furthermore, although the head shown in Fig. 17 can have a sufficiently large film, it is necessary to separate the oxide magnetic material one by one, coat the metal magnetic film, and then assemble it, which requires a large number of production steps and is not suitable for mass production. do not have.

The heads shown in Figs. 19 and 20 are made of metal magnetic gM.
The surface on which the film is formed has a complicated shape, and internal stress is generated during the process of forming a film on this surface, causing problems in ensuring uniform quality, such as making it impossible to obtain desired magnetic properties.

Furthermore, since each of the conventional examples uses a ferromagnetic oxide such as ferrite as a substrate, the selection range of expansion coefficient and abrasion resistance is limited to some extent, making it difficult to compatibility with metal thin films. Further, when the substrates are butted against each other to form a gap, if a positional shift occurs, a gap is likely to occur between the metal NH and the substrate, resulting in a problem in that the performance of the head changes.

Therefore, it is an obvious object of the present invention to provide a composite magnetic head that is highly productive and has stable performance with relatively low magnetic resistance when used in a high frequency range.

(Means for Solving the Problems) In order to achieve the above object, the magnetic head of the present invention has a non-magnetic head in which a metal thin film is formed on a thin film forming surface that is substantially orthogonal to both the gap facing surface and the tape sliding surface. A pair of substrates made of magnetic material are arranged diagonally to form a gap with the metal thin film, and these are joined by a non-magnetic material filled between the metal thin film of one substrate and the other substrate. ing.

(Function) Therefore, -lll! of the non-magnetic substrate! A metal magnetic thin film can be formed on the I wall surface in a direction substantially perpendicular to the gap, and the magnetic resistance can be made relatively small by making the metal magnetic thin film large.

(Example) The structure of the present invention will be described in detail below based on an example shown in the drawings.

FIG. 1 shows a perspective view and a side view of an embodiment of a magnetic head according to the present invention. In the figure, reference numeral 1 indicates a pair of non-magnetic substrates, on which a metal magnetic film 4 is deposited. The non-magnetic substrate 1 is usually made of ceramics, but is not limited to this. W! :! By arranging a pair of non-magnetic substrates 1 having 4 formed thereon diagonally, it is formed between opposing thin metals 11R4. still,
The metal thin film 4 is formed into a multilayer film having a thickness of at least 5 to 6 μm per layer on a side wall surface/thin film forming surface 6 that is substantially orthogonal to the gap facing surface 3 and the tape sliding surface 5 of the substrate l. There is. Also, in FIG. 2, among the four blocks divided by the metal thin film 4 and the magnetic gap g,
Two blocks located on the diagonal line are a pair of non-magnetic substrates 1, and the other two blocks are blocks 7 made of non-magnetic material, such as glass for fusion. Note that 12 is a winding groove.

Next, an example of a method for manufacturing the above-described magnetic head will be described.

(1) First, as shown in FIG. 2, on the gap facing surface 3 of the substrate 1 made of a non-magnetic material such as ceramics, a track holder 13 having a shape such that at least one side wall surface 6 is substantially perpendicular to the gap facing surface 3 is attached. It is formed in a direction perpendicular to the tape sliding surface 5. Normally, this groove machining is performed using a grinder.6 Note that when Sendust alloy is used as the metal thin film, a substrate made of a non-magnetic material, so-called non-magnetic material, is preferable from the viewpoint of wear resistance.

(2) Next, as shown in FIG. 3, a ferromagnetic metal such as Sendust alloy and a non-magnetic material such as 5i02 are alternately sputtered onto the track groove 13 in the direction of the arrow, or a crystalline ferromagnetic metal and an amorphous metal are sputtered. A multilayer metal thin film 4 is formed by alternately sputtering or by intermittently sputtering a ferromagnetic metal.

However, the last layer is a nonmagnetic film.

In addition, even if the sputtering direction of the metal thin film 4 approaches the direction of the broken line arrow in FIG. 3, increasing the sputtering gas pressure will shorten the mean free distance of the deposited particles and create a surface substantially parallel to one sputtering direction. can be formed efficiently.

(2) Next, the gap facing surface 3 is polished and lapped as shown in FIG. 4 to remove the metal magnetic film 4 on the gap facing surface 3.

(2) Next, a coil winding groove 12 is formed on the gap facing surface 3 side as shown in FIG. 2. The winding groove 12 is formed after the track groove 13 is formed, and then the above-mentioned
There is also a method of implementing the process.

(2) Next, a spacer 2 made of a non-magnetic material such as 5i02 is formed on the lapped gap facing surface 3 by sputtering or the like (see FIG. 6).

(2) The pair of substrates 1.1 thus obtained are stacked one on top of the other, as shown in FIG. 7, so that the metal thin films 4 formed on the side wall surfaces 6 face each other. Then, the track groove 13 is filled with a non-magnetic material 7 such as glass and bonded (gap bonding).

(2) Thereafter, as shown in FIG. 8, the metal thin film portion 10 at the bottom of the track groove 13 is cut off so as not to remain. This is because the metal thin film portion 10 at the groove bottom has a complicated shape and is distorted due to internal stress, and if this portion is left, the characteristics of the metal thin film 4 will deteriorate.

(2) The metal thin film [4] is cut so as to leave a portion substantially perpendicular to the gap g to obtain the magnetic head shown in FIG.

Although the above-described embodiment is a preferred embodiment of the present invention, the present invention is not limited thereto, and various modifications can be made without departing from the gist of the present invention.

For example, FIG. 9 shows another embodiment. In this magnetic head, the non-magnetic substrate 1 in the vicinity of the gap g is used to prevent the situation where the gap accuracy is not achieved due to direct contact between the metal thin film 4 and the hard non-magnetic substrate 1 when the metal thin films 4 are butted together. The gap-opposing surface of is tilted at an angle of 10° or more with respect to the gap g.

Specifically, as shown in FIG. 10, a recess 8 is formed in the gap-opposing surface 3 of the non-magnetic substrate 1 adjacent to the side wall surface 6, and a low-melting-point melt is applied to the recess 8 as a non-magnetic material. The inclination angle θ of the side wall surface of the recess 8 with respect to the magnetic gap g is approximately 45° in the figure, but the angle can be adjusted within the range of about 10 to 80°. It is also possible to change. Here, if the angle is less than 10 degrees, there is no point in providing the four parts 8 and filling the fused glass, so it is preferable to have an angle of 30 degrees or more.

This recess forming process is usually carried out before the process shown in FIG. 2 and track groove forming. The recess 8 is formed by cutting separately from the track groove 13, and is filled with a non-magnetic material 16 such as glass and polished into the shape shown in the figure. Note that the side wall surface 6 for forming the metal thin film 4
The ratio of the non-magnetic material portion A to the track width is 17% of the track width.
It is estimated to be 5 to 4 times more prevalent.

Also, after the sputtering process shown in FIG.
3 is filled with a non-magnetic material 16 such as glass, and then through the steps shown in FIGS. 4 and 5, erasers 8.11 are processed on both sides of the metal 4 film as shown in FIG. 11 to match the track width. It may also be secured by

In this case, the track width is regulated by the grinding steps 8 and 11a, but the track width can be regulated with only step 8, so grinding step 11 is not necessarily required.

Incidentally, the holes 8 and 11 are filled with a non-magnetic material 16 such as glass in the gap bonding process shown in FIG.

Furthermore, the aforementioned four parts 8 can also be provided after the metal thin film 4 is formed. Alternatively, as shown in FIG. 21, the upper side 14 of the layered thin film may be cut, the track width may be adjusted to a predetermined width, and then low melting point glass may be filled. In this case, a part of the high melting point glass 15 covering the metal thin film 4 is cut away, but is filled with low melting point glass 16 during gap bonding.

The cut-off thin pA4 end surface 14 is covered with low melting point glass and is not exposed to the gap facing surface 3.

In this case, it is not necessary to cut the tip of the thin film 4 on the substrate side, but if necessary, it may be cut by providing the recess 8 after forming the metal thin film 4 as described above. The technique can also be used when the substrate is a magnetic substrate.

Since these magnetic heads form the gap width by slightly cutting the edge of the thin film in the vicinity of the magnetic gap, the generation of residual stress due to cutting is extremely small, and the influence on the film properties is small, and a decrease in Q can be prevented. Furthermore, the surface on which the metal thin film is formed and the width of the gap can be easily processed and the precision can be easily achieved, making it suitable for mass production.

Furthermore, in the step shown in FIG. 8, the bottom portion 10 of the track groove 13 is removed, but if the gap has an azimuth angle, the bottom portion is removed from the chip core 9 side during slicing, as shown in FIG. ZS so that there are no 10s left
By slicing -S, the step of removing the bottom membrane portion 10 may be omitted. A magnetic head manufactured in this manner is shown in FIG.

Furthermore, after the step shown in FIG. 3, the metal thin film 4 may be filled with a non-magnetic material such as high-melting point glass to reinforce this film, and then the process shown in FIG. 4 is carried out. good.

Furthermore, the shape of the track groove is rectangular or trapezoidal, and the metal thin film 4 is formed on the front and rear parts of the same track groove 13.
It is also possible to manufacture a magnetic head with a uniform gap length using . This magnetic/magnetic head is manufactured as shown in FIG. 22.

First, a large number of rectangular or trapezoidal track grooves 13 having bilaterally symmetrical side wall surfaces extending in the transverse direction and in the direction orthogonal to the tape sliding contact surface 5 are formed on the gap facing surface 3 of the substrate 1 at a predetermined pitch. Form [Figure 22(a)]
Next, this substrate 1 is divided into two along a plane perpendicular to the above-mentioned transverse direction, that is, a plane parallel to the tape sliding surface 5, to form a pair of substrates IA.

Form IB [Fig. 22(b)]. Then, these are cleaned and a magnetic film 114 of ferromagnetic metal is formed using a vacuum thin film forming technique [FIG. 22(c)].

Usually, the magnetic film 4 is formed by sputtering a ferromagnetic metal such as Sendust alloy. This film is formed with the target facing the gap facing surface 3 so that the angle to the target is approximately 45 degrees. A pair of boards IA
, IB are placed facing the target and sputtered so that thin films on sidewall surfaces 6 opposite to each other are formed. That is, one substrate A and the other substrate IB are arranged in opposite directions with respect to the target. According to this method, the thin film 4 of ferromagnetic metal is formed so that the thickness becomes gradually thinner in the tape sliding direction, but it can be easily formed to a predetermined film thickness in the gap width direction, and A constant film thickness is formed in the depth direction to obtain a uniform gap length. For example, when a standard Sendust alloy is used as a target, sputtering is performed in an argon gas atmosphere at a substrate temperature of 200° C. at a rate of about 400 people/nin.

If fFUL and sputtering are carried out over a long period of time, there is a risk that the substrate temperature will rise during that time and the crystal grain size will become larger than 570 mm. Therefore, it is preferable to perform sputtering intermittently to cool the substrate.

Furthermore, it is preferable that one metal thin film is made into a substantial multilayer film so that each layer has a WA thickness of 5 to 6 μm, and usually by sputtering a ferromagnetic metal intermittently,
Alternatively, a magnetic thin film having a predetermined width is formed by sputtering a ferromagnetic metal and a nonmagnetic material alternately to form a plurality of layers.

Next, the track groove 13 is filled with high melting point glass 11 to protect the thin film 4 [Glass bonding Fig. 22 1)]
Thereafter, the gap facing surface 3 and the tape sliding surface 1 are ground to a flat surface with a predetermined surface roughness. Grinding is usually done by lapping to give a 3A finish. Thereafter, track regulating recesses 8 are ground next to the aforementioned grooves 13 along the grooves 13 to eliminate false gaps.

When grinding this recess 8, the metal thinner is 1 g! Adjust so that the gap width constituted by 4 becomes a predetermined width. After that, a winding groove 12 is formed on the gap-opposing surface 3 of one substrate IA [
FIG. 22(e)]. This winding groove 2 regulates the depth dimension. Note that the winding groove 12 is not formed on the other substrate IB. Next, a spacer 2 made of a non-magnetic material such as 5i02 is formed on the gap-opposing surfaces of both substrates LA and IB by sputtering. Next, one substrate is turned over so that the track grooves subjected to the same processing are overlapped, and then shifted in the width direction so that the left side wall surface of one substrate and the right side wall surface of the other substrate face each other6.
The aforementioned track regulating recess 8 is filled with low melting point glass 16 and bonded [gap bonding Fig. 22(f)]
, at this time, the side end of the ferromagnetic metal thin WA4 exposed on the gap facing surface 3 side.

Since a gap g is formed between the surfaces, accurate alignment is required so that the metal thin films 4 face each other. After the gap bonding described above, the tape sliding surface 5 is cylindrically ground to finish the tape sliding surface 5 into a curved surface [FIG. 22(g)]. Next, slices are made so that the magnetic gap g fits within a predetermined azimuth angle with respect to the tape sliding direction, and a large number of chip-shaped magnetic cores are cut out [Figure 22 (h)]. After that, the support head is inspected. It is attached to the base, and the sliding surface is finished for better conformability in the track direction, and then the wire is wound [Fig. 22(i)].

(Effects of the Invention) As is clear from the above description, according to the present invention, ■ As mentioned above, the film formed on the surface other than the flat surface on which the metal magnetic film is formed is subject to distortion due to internal stress. However, in the present invention, the portions of the chip portion 9 after slicing that are distorted due to internal stress (portions having shapes other than substantially planar shapes) are removed, so that the above-mentioned adverse effects can be completely prevented.

(2) Furthermore, since the metal magnetic film is formed in a direction substantially perpendicular to the gap, a large metal thin film can be formed over the entire surface of the magnetic head, reducing magnetic resistance and improving magnetic properties.

■ Furthermore, since a non-magnetic material is used as the substrate, the selection range of expansion coefficient and abrasion resistance is not relatively limited, unlike in the case of ferromagnetic metals, and it is compatible with thin metal films. was. Further, even if a slight positional shift occurs when the substrates are butted against each other to form a gap, no gap is generated between the metal thin film and the substrate, so the head performance is stable. In the case of a ferrite substrate, sliding noise was generated, but this does not occur in the case of the substrate of the present invention made of a non-magnetic material.

[Brief explanation of the drawing]

FIG. 1(a) is a perspective view showing an embodiment of the magnetic head according to the present invention, FIG. 1(b) is a side view of the same head, and FIGS.
FIG. 8 is a processing flow diagram showing an example of each step of the method for manufacturing the magnetic head, FIGS. 9 to 12 are views showing other embodiments of the present invention, and FIG. 9 is a plan view of the magnetic head. Figure, 10th
FIG. 11(a) is a side view of the track groove portion, FIG. 11(b) is an enlarged view thereof, FIG. 11(a) is a side view of the track groove portion according to another embodiment, and FIG. 11(b) is an enlarged view thereof. 12 are plan views of the magnetic core block. FIG. 13 is a plan view of a head showing another embodiment of the present invention, FIG. 14 is a plan view of the head cut out along the slice line shown in FIG. 12 in another embodiment of the invention, and FIG. FIGS. 15 to 20 are processing flow diagrams of a magnetic head according to an embodiment, without illustrating a conventional magnetic head. ■...Nonmagnetic substrate, 3...Gap opposing surface, 4...Metal thin film, 5...
・Tape sliding contact surface, 6... Side wall surface/thin film forming surface, 7
...Nonmagnetic material, g...gap. Patent applicant Sankyo Seiki Seisakusho Co., Ltd. Figure 1 Figure 15 Figure 16 Figure 17 Old figure 19 Figure 20

Claims (1)

[Claims] A pair of substrates made of a non-magnetic material on which a thin metal film is formed on the thin film formation surface that is substantially orthogonal to both the gap facing surface and the tape sliding contact surface are arranged diagonally, and the gap is formed with the metal thin film, A magnetic head is made by joining these together with a thin metal film on one substrate and a nonmagnetic material filled between the other substrate.