JPS58161125A - Magnetic head - Google Patents

Abstract

PURPOSE:To control the track width completely and to improve the yield, by forming a non-magnetic film between the first magnetic film and the second magnetic film, and estimating the quantity which is considered to be a factor of all variations to the thickness size of this non-mangetic film. CONSTITUTION:On a non-magnetic glass substrate 11, the first non-magnetic ground film 12 is formed by 3mum or so in thickness, and the first magnetic film 13 is formed by 15mum or so in thickness. In the following process, the second non-magnetic ground film 14 consisting of non-magnetic stainless steel which is same as the first ground film 12 is formed by 2mum or so by DC 4-pole spattering. Subsequently, a groove is formed by a V-shaped diamond cutting tool, a sample is inclined by 45 deg. against the horizontal plane, and by RF spattering, SiO2 is formed by 0.4mum or so on the gap formed face, as a gap spacer film 15. Subsequently, the second magnetic film 16 is formed by 20mum or so. After that, by a U-shaped diamond cutting tool, a U-groove is formed, and decision of the track width and the magnetic separation are executed. In this case, by film thickness of the second ground film 14, depth of the U-groove is controlled suitably.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a magnetic head having a structure that can be manufactured so that the track width of the magnetic head is always one foot.

FIG. 1 is a process explanatory diagram of a conventional magnetic head manufacturing method. The manufacturing process of a conventional magnetic head will be explained with reference to the same figure. That is, as shown in FIG. 1(1), a nonmagnetic base M2 and a first magnetic film 3 are formed on a nonmagnetic base @1. At this time,
The non-magnetic base film 2 is formed in about 1 to 6 layers, and the main purpose of the base film 2 is to prevent cracks, etc. on the non-magnetic substrate 1 due to V@shading formation in the step 1-(2). That is, the 0th order (
As shown in 2), the magnetic a3 forms a v#1 extending to the base film 2 using a diamond bite or the like, and the 10,000 slopes of the groove are used as the gap forming surface. (3) is a step of forming a non-magnetic gap spacer material (film) 4 for forming a gap, and the thickness of the spacer film 4 is formed so as to obtain a desired gap length. At this time, the gap spacer film 4 may be formed only on the slopes of the 10,000 grooves, but generally the gap spacer film 4 is formed on the entire surface of the #1 portion by using a mask batter or the like. (4) is a step of forming the second magnetic film 5 from above the gap spacer film 4, and (5) is a step of forming a groove in a part of the second magnetic film 5 using a U-shaped tool (not shown) or the like. (
This is a step of forming and removing a depth D). At this time, the step of removing a part of the second Mi property M5 by the 0-character byte requires 2
One of them is to control the track width TO of the tube, which is determined by the thickness of the first magnetic film 5, and the other is to control the track width TO of the tube, which is determined by the thickness of the first magnetic film 5. Tono l! IK: #Emotional separation! It's about getting.

(6) is a step of forming the retaining S narrower 6 from above the second magnetic film 5, and after that, the head is fabricated through steps (not shown) of forming the winding holes 2, the winding 1, etc.

The biggest drawback of the conventional head whose Lv was created through the steps described above is the difficulty in controlling the track width through the step shown in FIG. 1 (5). In other words, when forming a groove using a U-shaped cutting tool, etc., it is difficult to control the depth D, and if the groove is formed shallowly, the upper surface of the spacer film 4 remains covered by the second magnetic M5, and the gap borders the gap. The first magnetic field a
Moreover, if the depth is too deep, the thickness of the first magnetic film 3 will be engulfed, and the track width will become small. The gap spacer film 4 is provided to form a gap, but since the gap in a normal VTR head is at most [L5 to α6 μs], the gap spacer film is also formed on the flat 60 parts other than the corners. Although it is possible to use this thickness as thick as possible to prevent the above drawbacks, it is no longer possible to freely form only the thickness of the gap spacer film on the plane part to an arbitrary film thickness regardless of the gap part. Therefore, it is inappropriate to use this for track width control. Therefore, there is a need for a magnetic head having a structure that allows accurate control of the track width T regardless of the gap spacer film.

SUMMARY OF THE INVENTION An object of the present invention is to provide a magnetic head having a structure that eliminates the above-described drawbacks in track width control of the prior art, has accurate track width dimensions, and can be easily produced with high yield.

The main point of the present invention is that, in order to solve the difficulty of track width control, which is a drawback of the conventional technology, a deep groove is formed between the first magnetic film and the second magnetic film to prevent warping of the substrate and to prevent the gap surface from being machined. A non-magnetic material is placed with a thickness that takes into account error factors in the groove dimensions when forming the grooves of the second magnetic film thickness distribution.
It is. This non-magnetic layer is different from a skin gap spacer film that forms a gap, and does not necessarily have to be on the entire surface.

Next, an embodiment of the present invention will be described with reference to the drawings.

The second figure is an explanation of the manufacturing process of a magnetic head as an embodiment of the present invention. The following description will be made with reference to the same. Second
Cap (1) is a non-magnetic glass substrate (component is 5i02A
Ji1201-L102-20 has a thermal expansion coefficient of 130
XIQ'1 deg,
US510 was formed to a thickness of 3 μm using DC 4-pole sputtering, and then a sendust film was formed as the first magnetic film 15 using 5US510 and four-way KDC 4-pole sputtering! A thickness of 15 μm is formed at a rate of 510 μm/hr. Since the hardness of the underground M12 made of 5U8510 is the same as that of the sendust film as the first magnetic film 13, it is convenient for cutting when forming the L groove in the V-shaped diamond bite in the process shown in FIG. 2 (3). It is a good material. (2) In the O process, the track width control according to the present invention is performed, and the first base film 12 and the fourth base film 5US5 are used.
The second non-magnetic base film 14 consisting of 10
Form 2 μl by polar sputtering.

That is, as mentioned previously, the main purpose of the non-magnetic base film 12 of @1 is to prevent cracks in the lath 11 of the substrate when grooves are formed with a V-shaped cutting tool. The main purpose of the underlayer a14 is to control the track width necessary in step (6) v in FIG. 2.

(8) is a groove forming process using a V-shaped diamond bite;
The 10,000 slopes of this bird are used as gap forming surfaces. The tip angle of the V-shaped cutting tool is 951 in this example.
Figure 2 (3) using 1 byte ■α is the byte and lWJ 9
An angle of 5@ was obtained. Also, at this time, Figure 2 (31Q)
# is the azimuth angle of the head, which is 17″ in this example.
and 30"'. In the second case (4), the Tov1 sample was set at 45° to the horizontal plane in the head gap formation process.
A film 5102 having a thickness of α4 μm is formed as a gap spacer film 15 on the gap forming surface by #I RF sputtering. The film thickness α4μ of the gap spacer film 15 is the gap length of this head. At this time, the thickness of 810z (gap spacer film 15) on the flat surface is the same or slightly smaller than that of 5i02 on the gap forming surface. Next, Figure 2 (5)
As the second magnetic film 16 indicated by K, a DC quadrupole sputtered dust film is formed as the second magnetic film 16 by removing the first magnetic film 13 in the same manner as described above. In this example, the sample was placed horizontally and sendust film sputtering was performed. Figure 2 (6) is an important step. 2
In the embodiment in which the magnetic film 16 is magnetically separated, U
A 19U groove is formed in the letter-shaped diamond bite to determine the track and perform magnetic separation, but the depth of the U@ can be controlled to the desired depth, that is, the second non-magnetic base *
If a groove is formed deep beyond 140 mm, the track transport will be reduced, and if it is too shallow to reach the base film 14, the magnetic field of the core (magnetic films 13 and 16) across the gap will decrease. No separation is formed, making it unsuitable as a head. That is, the warpage of the non-magnetic substrate 11 and the second fiB
The film thickness distribution of the magnetic film 16 by DC quadrupole sputtering, history is U
All variations in the mechanical accuracy of the character-shaped tool are the 21st V.
There are wrinkles in the process of (6), and unless this bounce is absorbed, correct control of the truck cannot be achieved.
In this embodiment, if a woofer with a 1-inch square glass substrate 11 is used, the warp of the substrate can be controlled to a maximum of about 1 μm, and the warping of the substrate can be controlled to a maximum of about 1μ.
The mechanical accuracy of the letter-shaped tool can also be controlled to 1 μII, and the thickness of the sendust film 16 is almost uniform. The thickness was set to 2 μm.

In addition, in another track smoothing process (7), the U
Since the F second magnetic film 16 is 20 μm thick on the letter-shaped cutting tool, a U groove depth of 15 μm is formed, and then an L groove is formed by sputter etching.
Etch the bottom of the U-groove by approximately 6μI.

At this time, the sendust film 16 on the flat part other than the groove part is also about 6 μm thick.
Although the etching process is continued, the remaining film thickness can be maintained at 14 μm. Since the film thickness of the base film 14 of j1!2 according to the present invention is 2 μm, variations in the precision of the U-shaped cutting tool and the sputtering error t are sufficiently absorbed, and the track width, which is the objective of the present invention, is fully absorbed. Accurate control can be easily achieved and product yields are also improved.

Another embodiment is shown in FIG. 3. In FIG. 3 (1), the non-magnetic substrate is Ak2! made of non-magnetic stainless steel material 5uS510 on the lath 21 (same as the 5j! embodiment). Rr sputter S! It is formed to a thickness of 4 μm using a power of about 5 W/cs2. It takes about 2 hours to form.

At this time, a23's fiUs! When changing the composition of 510 to nM1, care must be taken as it will be cloudy. And this v 5u
Sendust j [! 22 was formed to a thickness of 15 μm by DC 4-pole sputtering using the above-mentioned IHj method, and then an F groove was formed on the V-shaped diamond bite, and then, as gap spacer I [24, alumina with a large coefficient of thermal expansion of 8102 film was formed by RF sputtering. α4μI is formed on the entire surface. Dry it and cover the VSS with a mask. Apply R to the flat part other than the F-V groove s using the mask sputter. A 1.5 .mu.I film of F-alumina film 25 is formed on the mask. That is, the gap spacer film 24 and the non-magnetic film 25 for track width control according to the present invention are made of alumina films made of the same material, and the necessary film thicknesses are formed for each. 2
As the magnetic property 26, the first magnetic j [FIG. 3(3)
It is removed using a diagonal m5VU-shaped diamond bite in the process. In the non-example, the diamond bit alone was used for removal, but as in the previous example, sputter etching can also be used in combination. In this example, the second non-magnetic j[25 is VS
In the explanation, it is formed on the entire surface other than S, but it is formed on only the -1 dog and used in combination with the above embodiment, that is, a 2μ recess of alumina film is formed as the second non-magnetic film 25. After that,
A V-shape may be formed in the diamond bite, and then an alumina film having a thickness of α4 μm may be formed as the gap spacer film 24 on the V-groove portion or the entire surface.

Further, as shown in FIG. 4, which is still another embodiment, a 5US310 film 23 of 4 μl is formed as a first non-magnetic base film on the non-magnetic substrate glass 21 according to the above-mentioned embodiment, and a sender film is applied on the film.
15 μm of a22 is formed.

Thereafter, the alumina film 25 as the second non-magnetic film according to the present invention is removed only from the necessary portions by mask sputtering #I or by etching after sputtering on the entire surface to form a 2 μm film.
Form. As shown in Fig. 4 (2), a part of the alumina l[25 and sendust film 22 is cut into a diamond pad 9.4 to form a V-groove, and then (3) ), an alumina film 24 is formed as a gap spacer film by sputtering to a desired gap length. (4) is etched w1 on the U-shaped cutting tool as in the previous example.
Magnetic layer and track across the gap by removing s
Process.

In this example, in order to limit the non-magnetic a25 to the necessary minimum for track wheel control, we take precautions to prevent the adhesive strength of the film from decreasing due to the internal stress force KL as the film thickness increases. I can see the effect of improvement.

A schematic diagram of the sliding surface of a magnetic head as an embodiment of the present invention is shown in Fig. 5-, that is, the arrow in Fig. 5 indicates the main magnetic path of the magnetic head, and the first magnetic film is 1st layer main magnetic path 3
The magnetic film of the second layer is divided into a second layer main magnetic path 35 and a first layer main magnetic path 34.

#1 or 31 is a non-magnetic substrate, 52 is a first base film, s
3 indicates the gap, 58 indicates the retention film %, and 39 indicates the second base layer expansion.

According to the present invention, a nonmagnetic film is formed between the first magnetic film and the wJ2 magnetic film, and the overall machining accuracy is achieved by the #nonmagnetic layer thickness dimension, so that the track width machining accuracy is significantly improved. Then, the amount of the non-magnetic film formed between the first and second magnetic films, which is the cause of all variations, such as warpage of the non-magnetic substrate, variation in the thickness of the second magnetic film, and variation in processing amount due to the U-shaped cutting tool, etc. It becomes possible to completely control track smoothness by considering the film thickness dimension.

The present invention is particularly effective when applied to a case where a large number of heads are fabricated on a single non-magnetic substrate, in which case the amount of variation increases accordingly.

In this example, the groove shape is explained as a V-shape, but it is not limited to this shape, and the processed shape in the track width processing and magnetic separation process is also limited to the leading U-shape. In addition, the method is not limited to removal using a t-bite or sputter etching, and the combination of methods is not limited to only this example.
Although the first magnetic film W and the second magnetic film are described as a single-layer film, the insulating layer is, for example, 5 oz., considering the resistance of Sendust, etc., and the eddy current loss.

Non-conductive non-magnetic film such as ki205 α05~α1μms
It is clear that a multilayer magnetic layer may be formed by forming a multilayer magnetic layer, and this may be formed to a desired thickness to serve as the first magnetic film and the second magnetic layer, respectively.

[Brief explanation of the drawing]

Figures 1 (1) to (6) are process explanatory diagrams of a conventional magnetic head manufacturing method; Figure 3 (1) - (
3) is an explanatory diagram of the manufacturing process of a magnetic head as another embodiment, and 4th prisoner (1) to (4) is an explanatory diagram of the manufacturing process of a magnetic head as another embodiment. FIG. 2 is a schematic diagram showing a sliding surface of a magnetic hect as an example. Code explanation 1.11, 21.51...Nonmagnetic substrate, 2.12, 2
5.52...Nonmagnetic base film, 3.1! S, 22154
．． 36... first magnetic gland, 4, 15, 24. ! SiS・
・Gap spacer film, 5°16.26. ! 55.3
7...Second magnetic film, 6,38...Main farming, 14.2
4, 25.59...Second foundation exhibition. Agent ffj! 1 Shi Usui 1) Ri Yukibu l Figure (1) (2) (3) (4) Sai2 Figure (3) (4) (5) (6) /1 (7) Fang 3 Figure 127- 5 Continuation of figure 1 ■ Inventor Hozo Tamura 1410 Oaza Inada, Katsuta City, Tokai Factory, Hitachi, Ltd.

Claims (1)

[Claims] 1. A first magnetic film is formed on a non-magnetic substrate, a non-magnetic base film is formed thereon, and the first magnetic film is formed from the surface of the base film.
A groove is formed that penetrates the thickness of the magnetic film, and in order to make at least one slope of the groove a gap surface, a non-magnetic film (hereinafter referred to as a spacer film) serving as a gap spacer is deposited on the slope, Further, after depositing a magnetic film @2 on top of the second magnetic film, a material is applied from the surface of the second magnetic film to the thickness range of the non-magnetic base film near the top of the slope on which the spacer film is deposited. By removing the first
1. A magnetic head comprising: a magnetic film and a second magnetic film sandwiched between them and magnetically separated by a film between the first and second magnetic films. 2. In the magnetic herad according to claim 1,
The groove is formed so as to penetrate from the surface of the first magnetic film through its thickness, and the non-magnetic base film is made of the same material as the spacer film deposited on at least one slope of the groove, and the spacer film is A magnetic head characterized by being formed thicker.