JPS61292215A - Thin magnetic head and its production - Google Patents

Abstract

PURPOSE:To obtain a gap surface having good linearity and high accuracy without roughening by providing a relief to the 1st magnetic film formed on a nonmagnetic substrate thereby decreasing tool wear as far as possible. CONSTITUTION:The 1st magnetic film 3 consisting of 'Sendust(R)', 'Permalloy(R)', amorphous, etc. is formed to an L shape by mask sputtering, etc. on a nonmagnetic substrate. The part of the 1st magnetic film 3 corresponding a front core is subjected to multi-stage machining with slight cut-in using a tool having the hardness higher than the hardness of the magnetic film 3 to form a gap forming surface 4. A nonmagnetic gap spacer 5 such as SiO2 is formed on the surface 4 by as much as the thickness at which a desired gap length is obtainable and the 2nd magnetic film 6 is formed thereon to flatten the surface. The nonmagnetic substrate is formed as a head protective material 7 and a winding window 8 is formed by ultrasonic working, etc. A winding 9 is wound to the window.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a thin film magnetic head and a method for manufacturing the same, and more particularly to a thin film magnetic head suitable for use in a VTR and the like and a method for manufacturing the same.

[Background of the invention]

In a conventional thin film magnetic head, as described in Japanese Patent Application Laid-Open No. 12119/1983, a core made of a magnetic thin film formed on a non-magnetic substrate is cut with a diamond cutting tool over the entire chip to form a gap surface. It was manufactured by the method.

The method of forming a gap surface using a diamond cutting tool is a very effective method, as it is possible to form a highly precise gap surface by directly transferring the cutting edge line onto the gap surface in the film thickness direction. The reality is that even if you use a diamond tool, wear of the tool is unavoidable.

Conventional methods also have the disadvantage that tool bit wear (wear on the edge of the cutting tool, reactive wear in minute areas) occurs, resulting in deterioration of gear tooth linearity and roughening of the gap surface. Therefore, it becomes necessary to re-sharpen the cutting tool that has reached a predetermined amount of wear to correct its ridgeline, which poses a problem in terms of mass production.

[Purpose of the invention]

The purpose of the present invention is to eliminate the drawbacks and problems of the above-mentioned prior art,
It is an object of the present invention to provide a thin film magnetic head and a method for manufacturing the same, which improve the life of the tool by reducing wear on the tool as much as possible and have a high precision gap surface with good linearity and no roughness.

[Summary of the invention]

In order to achieve this objective, the present invention takes into account the following two points: the amount of wear on the cutting tool is approximately proportional to the machining length, and in the past, cutting tool machining was performed even to parts that did not require machining.
Paying attention to this point, when forming the gap surface with a cutting tool,
The feature is that a relief is provided in the first magnetic film formed on the non-magnetic substrate so that only the part that will become the front core is removed, thereby shortening the cutting time and suppressing tool wear. There is.

[Embodiments of the invention]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view showing an embodiment of a thin film magnetic head according to the present invention, in which 1 is a thin film magnetic head, 2 is a nonmagnetic substrate, 3 is a thin film magnetic head, and 3 is a thin film magnetic head. 4 is a first magnetic film, 4 is a gap forming surface, 5 is a gap, 6 is a second magnetic film, 7 is a protective material, 8 is a winding window, and 9 is a winding wire.

In the figure, the return magnetic head 1 has a first magnetic film 3 with a recess formed on a non-magnetic substrate 3, which has a recess for shortening the machining time of a cutting tool used when forming the gap forming surface 4.
formed in the soil. Furthermore, in the first magnetic film 3, f
l In the final head shape, half of the so-called front core part from the sliding surface to the winding window 8 is removed, and S
The structure is such that a gap 5 is formed with a second magnetic film 6 formed in the removed portion via a non-magnetic material such as i02. The protective material 7 is a nonmagnetic substrate or a nonmagnetic film such as S i 02 or 7 orsterite, and is used to protect the head. In addition, the winding window 8 has a winding IIji9.
Next, a method for manufacturing the thin film magnetic head according to the present invention shown in FIG. 1 will be explained with reference to FIG. 2.

FIGS. 2(α) to (!I) are manufacturing process diagrams of a thin film magnetic head according to the present invention. As shown in FIG. 2(α), sendust, permalloy, etc. A first magnetic film 3 made of amorphous or the like is formed into an L-shape by mask sputtering or the like. This is because the first magnetic film 3 is provided with a relief in order to minimize the amount of magnetic film removed by a cutting tool, which will be described later. Next, as shown in FIG. If this removal process is performed using a cutting tool with a higher hardness than the first magnetic film 3 (for example, a diamond cutting tool) and multi-stage cutting with minute cuts of about 1 μm, the cutting resistance can be reduced and a good gap surface can be obtained. Regarding the cutting tool, the cut is made until the surface of the non-magnetic substrate 2 is reached, and the angle θ (corresponding to the azimuth angle) between the gap forming surface 4 and the normal line of the non-magnetic substrate 2 is 08 to 30 degrees. If the magnetic film removal process in this process is performed from the front core part to the rear core part as in the past, the cutting tool will require approximately 20
00 μm, whereas when applied only to the front core portion as described above, the length for hide processing can be reduced to about 1/20, to about 100 μm, which is the length corresponding to the gap depth. Next, as shown in FIG. 2C, a nonmagnetic gap spacer 5 such as S i 02 is formed on the previously formed gap forming surface 4 by mask sputtering or the like to a thickness that provides a desired gap length. Next, the same figure (
As shown in d), a second magnetic film 6 is formed on a portion of the nonmagnetic substrate 2 where the first magnetic film 3 is not formed. Second
The magnetic film 6 must be slightly thicker than the first magnetic film 3. Next, as shown in (-) in the figure, the second magnetic film 6 is removed by lapping and flattened until it has the same thickness as the first magnetic film 3. At this time, the rear connection portion, which is the boundary between the first and second magnetic films, has no effect on the magnetic circuit of the head as a whole. Then, as shown in FIG.
If a non-magnetic film such as is formed by a method such as sputtering, a winding window 8 is formed by ultrasonic processing etc. as shown in the same figure (!i), and a winding @9 is wound, the result shown in Fig. 1 is obtained. The shown thin film magnetic head 1 can be manufactured.

According to this embodiment, the gap surface formation by the cutting tool is limited to only the front core portion required as the working gap,
Extremely short cutting time (approximately 1/20th of the conventional length)
Therefore, it is possible to not only suppress tool wear and improve the service life by about 20 times, but also to obtain a thin film magnetic head having a highly accurate gap surface with good linearity and no roughness.

Although the above embodiment relates to a single gap head, the present invention may be applied to a double gap head and both slopes of the magnetic film removed portion may be used as gap forming surfaces.

An example will be explained with reference to FIG.

FIG. 3 is a manufacturing process diagram showing another embodiment of the thin film magnetic head according to the present invention, and is shown at (α) in FIG.

(A) corresponds to (b) and (y) in FIG. 2, respectively.

In FIG. 3, a first magnetic film 3 with a relief in the rear core part is formed on a non-magnetic substrate 2 by a method such as mask sputtering, and a gap is formed by cutting only the front core part required as an operating gap. Set it to side 4. Hereafter, the third
A double-gap thin film magnetic head 1' shown in FIG. 3(h) is obtained.

Although the above is an example for a single head, the invention can also be extended to a wafer.

FIG. 4 shows an example in which the single gap head shown in FIG. 1 is developed on a wafer, and the figure shows the state in which the front core portion of the first magnetic film 3 has been removed by a cutting tool. This is a perspective view and corresponds to (ri) in FIG.

In the figure, a large number of magnetic heads developed on a wafer are ultimately separated into individual Herad chips, and one
0 is the cutting margin for that purpose.

When developed on a wafer, there is an advantage that a large number of thin film magnetic heads with highly accurate gaps can be manufactured with good workability.

〔Effect of the invention〕

As explained above, according to the present invention, by providing a relief in the first magnetic film, the gap forming surface that becomes the working gap is limited to only the front core portion, and the forming tool for the cutting tool is used for machining. By shortening the time, it is possible to suppress tool wear, making it possible to mass-produce thin-film magnetic heads with a high-precision gap surface with good straightness and no roughness.
It is possible to provide a thin film magnetic head with excellent functionality and a method for manufacturing the same, which eliminates the drawbacks of the prior art described above.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing the actual male side of the thin film magnetic head according to the present invention, FIGS. 2 (α) to (1) are manufacturing process diagrams of the thin film magnetic head according to the present invention, and FIG. 3 is a diagram showing the manufacturing process of the thin film magnetic head according to the present invention. FIG. 4 is a manufacturing process diagram showing another embodiment of the thin film magnetic head, and is a perspective view of the single gap head shown in FIG. 1 developed on a wafer. 1... Magnetic thin film head, 2... Nonmagnetic substrate, 3...
・First magnetic film, 4... Gap forming surface, 5... Gap, 6... Second magnetic film, 7... Protector, 8...
... Winding S window, 9... Winding, 10... Cut. Representative Patent Attorney Katsuo Ogawa No. 1, No. 20 (α) No. 2Z Defense 3 ('L)
(Lev O

Claims (2)

[Claims] (1) A first magnetic film formed on a nonmagnetic substrate;
A gap surface formed on the slope of the magnetic film by removing one end of the magnetic film, a non-magnetic film formed on the gap surface to a thickness such that the desired gap length is formed, and a first magnetic film formed on the gap surface and the first magnetic film. A second magnetic film formed flat on a non-magnetic substrate portion where no film is formed, a winding window formed through the non-magnetic substrate including the first and second magnetic films, and a winding window. In a thin film magnetic head comprising a winding wire applied to the first magnetic film, the rear core portion of the first magnetic film, that is, the portion extending from the winding window to the rear end of the head in the final head shape forms a gap in the front core portion, that is, In the final head shape, the first part is formed in an L-shape that escapes to the outside of the long line from the sliding surface to the winding window, that is, to the side surface of the head.
A thin film magnetic head characterized in that a magnetic film is formed thereon. (2) A first magnetic film is formed on a non-magnetic substrate, one end of the first magnetic film is removed and its slope is used as a gap surface, and the thickness is set so that the desired gap length is obtained on the gap surface. After forming a non-magnetic film on the gap surface and on the non-magnetic substrate portion where the first magnetic film is not formed, a second magnetic film is formed and flattened to form the first and second magnetic films. A winding window is formed that penetrates the non-magnetic substrate, and winding is applied to this window.
Regarding the first magnetic film, the rear core part, that is, the part from the winding window to the rear end of the head in the final head shape is the front core part, that is, the part from the sliding surface to the winding window in the final head shape. In a method for manufacturing a thin film magnetic head in which a magnetic film is formed in an L-shape such that it escapes to the outside of an extension line of a portion extending to the side surface of the head, one end portion of the L-shaped first magnetic film that becomes a front core. A method for manufacturing a thin film magnetic head, characterized in that only the thin film magnetic head is processed using a cutting tool, and the slope thereof is used as a gap forming surface.