JPS61142517A - Production of thin film magnetic head - Google Patents

Abstract

PURPOSE:To remove the defective control of gap depth at the spherical working of the sliding surface of a recording medium and to improve the yield by arranging a gap depth monitor between head tracks. CONSTITUTION:The gap depth monitor 9 having about 3-10mum width and consisting of Fe-Ni alloy, Fe-Al-Si alloy, etc. is formed between the head tracks 8. The monitor 9 is formed like a triangle or sector obtained by extending lines expanded from the intersecting point E of the center line between the head tracks and a line setting up the gap depth values G, D to zero in the gap depth G, D direction so that angles theta, theta' become equal up to the inside lines of respective head tracks and connecting the intersecting points F, G of said extended line and the inside lines of respective head tracks by straight lines or curved lines. An approximately rectangular recording medium sliding surface 14 is formed on the opposite surfaces of a pair of a lower magnetic thin film 2 and an upper magnetic thin film 6 by machine working such as lapping, the change of the width of the monitor 9 is read out by a microscope or the like and the gap depth values G, D are calculated to finish the recording medium sliding surface like a spherical surface.

Description

DETAILED DESCRIPTION OF THE INVENTION FIELD OF INDUSTRIAL APPLICATION The present invention relates to a method of manufacturing a thin film magnetic head that can be used in various magnetic recording and reproducing devices such as Flo, 'JB disk devices and video tape recorders.

A conventional thin film magnetic head is a highly accurate magnetic head that makes full use of semiconductor manufacturing methods such as thin film formation technology and photolithography technology. Conventionally, a core of a magnetic head has been manufactured by machining, such as grinding or lapping, a magnetic material such as ferrite or sendust, and a wire is wound around the core. Therefore, high precision is achieved.

In recent years, there has been a growing interest in thin-film magnetic heads as mass production has reached its limits, and mass production of some of them has begun. Thin-film magnetic heads are manufactured using thin-film formation technology and photo-etching technology, making it easy to downsize and increase precision.Furthermore, since the magnetic core is made of a thin film, (1) magnetic permeability at high frequencies is low. Less deterioration.

(2) The head magnetic field that contributes to recording is steep, allowing high-resolution recording.

(3) When multi-track is used, the area facing adjacent tracks is very small, so crosstalk between each head is almost non-problematic.

Problems to be Solved by the Invention Thin-film magnetic heads have many advantages as described above, but since the magnetic head is formed from a thin film, it is extremely difficult to make multiple windings due to the structure and manufacturing method, and the recording current is low during recording. increases, and the reproduction output voltage decreases during reproduction. In order to reduce the recording current and increase the reproduction output voltage, it may be possible to reduce the gap depth compared to conventional magnetic heads. However, reducing the gap depth shortens the life of the thin-film magnetic head, so It is important to control the

The gap depth of a thin film magnetic head is controlled by depositing a metal thin film with a thickness of about 0.1 μm during thin film formation and etching it into a rectangular shape. Leads are taken out from both ends of this rectangular metal thin film using a metal thin film with low resistivity, and the entire Giyoung depth monitor is formed, and the entire width of the metal thin film is reduced by processing the recording medium sliding surface. A method is used to calculate the gap depth based on changes in resistance, and this gap depth monitor is attached to both ends of the head track to sense the gap depth at two locations and is configured to suppress variations in gap depth. has been done. Thin-film magnetic heads use a method in which the sliding surface of the recording medium is shaped into a spherical surface in order to improve the contact between the sliding surface of the recording medium and the recording medium. The error between the gap depth monitor and the gap depth monitor became large, making it impossible to accurately control the gap depth. Furthermore, if the radius of the spherical surface of the recording medium sliding surface is made small, the contact area will be reduced, resulting in severe wear, and since only the center of the spherical surface will be in contact, the contact performance will not be good considering the entire head track. In addition, when the radius is increased, the contact area becomes larger and it is difficult to obtain a proper contact condition.The present invention solves the above-mentioned conventional problems and makes it possible to control the gap depth with high precision. It is something.

Means for Solving the Problems The method of the present invention is characterized in that a gap depth monitor is installed between the head tracks.

Operation According to the present invention, it is possible to provide a thin film magnetic head with high yield by controlling the gap depth t with high precision and eliminating poor gap depth control when machining the recording medium sliding surface into a spherical surface.

Embodiment FIG. 1 is an exploded perspective view of a thin film magnetic head manufactured by the method of the present invention, FIG. 2 is an enlarged plan view of the main part in FIG. 1, and FIG. It is a front view.

This will be explained based on FIG. 1, FIG. 2, and FIG. 3. Vapor deposited on a substrate 1 such as ceramic.

Fe-Ni alloy, Fe-Al
1°-St gold alloy is deposited to a thickness of 3 to 10 μm and etched.

A pair of lower magnetic thin films 2 are formed by a method such as lift-off. Furthermore, S t O2, AIl, which becomes the head gap,
The first insulating thin film 3 is attached with a thickness of about 0.6 to 1 μm.
After forming gold, a conductor such as Cu or Ag is deposited thereon by vapor deposition or electrodeposition to form a pair of windings 4 and leads 5. Furthermore, in order to electrically insulate the winding 4 and the upper magnetic thin film 6, a second insulating thin film 7 is formed of 7-otoresist, 3102, etc., and is further magnetically coupled to the lower magnetic thin film 2 on the second insulating thin film 7 at the rear. At the same time, a pair of upper magnetic thin films 6 are formed between the head tracks 8 with a gap depth monitor 9 of about 3 to 10/Am made of Fe-Ni alloy, Fe-
It is made of An-8i alloy or the like. Gap depth monitor 9
are the center line between the head tracks and the gap depth G, D
) is zero, extend a straight line that extends in the gap depth G and D) directions to the inner line of each head track so that the angles θ and θ' are the same, and then Intersection point F of the inner lines.

Make a shape such as a triangle or sector by connecting G with straight lines or curves. In order to protect the lower magnetic thin film 2 and the upper magnetic thin film 6 from abrasion caused by sliding of the recording medium 10, A2203°8102 or the like is deposited to a thickness of 30 to 40 μm by sputtering, vapor deposition, etc. to form a protective thin film 11. In order to eliminate the resulting unevenness of about 20 μm, the protective thin film 11 is flattened by lapping or plasma processing. In order to stabilize the sliding movement of the recording medium 10 and protect the thin film portion, a cover material 13 such as glass is bonded with an adhesive 12 such as resin or glass. The arrow indicates the recording medium sliding direction. A gap such as a triangle formed by cutting the recording medium sliding surface 14 substantially perpendicular to the opposing surfaces of the pair of lower magnetic thin film 2 and upper magnetic thin film 6 by machining such as lapping in the thin film portion formed as described above. depth monitor 9
Read the change in the width using a microscope etc. and determine the gap depth G, Di
Calculate and finish into a spherical surface. Also, the gap depth G between the head tracks 8.

To adjust the balance of D, read the dimensions C and Di of the gap depth monitor 9 and the head track 8 with a microscope, and check the dimensions C.
Process so that the dimensions are the same. Note that the broken line in FIG. 2 indicates the state before processing. As described above, by attaching the gap depth monitor 9f between the head tracks 8, variations in the gap depths G, D of the thin film magnetic head and the head tracks 8 can be suppressed.

Next, another embodiment will be described. A thin film portion is formed in the same manner as in the previous implementation, and the head track 8 and the 4 portions of the conductor winding are scratched by machining using a grinder or the like to increase the width of the recording medium sliding surface 14 in the sliding direction of the recording medium 10. The surface area of the recording medium sliding surface 140 is reduced by grinding to the extent that there is no surface area. Furthermore, by finishing it into a spherical surface with a large radius of about 20 to 50 mm using a method such as lapping, it is possible to obtain a recording medium sliding surface 14 with less wear and good contact with the recording medium 10, thereby reducing the deterioration of the reproduction output voltage. It can be eliminated.

Effects of the Invention The present invention forms a gap depth monitor between the head tracks of a pair of thin-film magnetic heads, reduces the area of the recording medium sliding surface in the recording medium sliding direction, and makes the recording medium spherical. Since suitable contact between the medium sliding surface and the recording medium can be achieved and the gap depth dimension can be stably processed, a high-output thin-film magnetic head can be provided with a good manufacturing yield, and its practical effects are significant.

[Brief explanation of drawings]

FIG. 1 is a perspective view of a thin film magnetic head according to an embodiment of the present invention, FIG. 2 is an enlarged plan view of main parts in FIG. 1, and FIG.
The figure is a BB/cross-sectional view in figure 82. 4...Winding, 6...Lead, 8...
...Head track, 9... Gap depth monitor, 10... Recording medium, 14...
Recording medium sliding surface. Name of agent: Patent attorney Toshio Nakao and 1 other person 1st
Figure 2, 4 Figure 3

Claims (2)

[Claims] (1) A lower magnetic thin film is formed on the substrate, a winding and a lead are formed with a conductive thin film through a first insulating thin film which becomes a head gap on the lower magnetic thin film, and a second conductive thin film is formed on the conductive thin film. A method for manufacturing a thin film magnetic head comprising a pair of thin film magnetic head elements in which an upper magnetic thin film is formed so as to be magnetically coupled to the lower magnetic thin film at the rear through an insulating thin film, the gap depth monitor comprising: A gap depth monitor is formed between the head tracks of the thin-film magnetic head, and a recording medium sliding surface that is approximately perpendicular to a plane where the lower magnetic thin film and the upper magnetic thin film face each other is formed using the monitor as a reference. A method of manufacturing a thin film magnetic head characterized by processing it into a spherical surface. (2) The method for manufacturing a thin film magnetic head according to claim 1, wherein the gap depth monitor is triangular.