JPH0487007A - Thin film magnetic head - Google Patents

Abstract

PURPOSE:To increase the thickness of an oblique part of an upper core so as to prevent the magnetic saturation of the oblique part and then to improve the recording efficiency, the reproducing efficiency, and the sensitivity of a thin film magnetic head by setting the front edge of the flat part of an upper core of the head produced by a thin film forming technique at a position ahead of the zero point of lifetime of a magnetic gap. CONSTITUTION:The front edge P of the flat part of an upper core 8 of a magnetic head produced by a thin film forming technique is set at a position ahead of the zero point of lifetime of a magnetic gap 12. Meanwhile the rear edge part of the gap 12 set at its depth direction, i.e., a flat part 8a of the core 8 set higher than the zero point of lifetime of the gap 12 is set at a position ahead of the edge P. At the same time, the part between the part 8a and the gap 12, i.e., the thickness of the oblique part of a conventional upper core is increased than other parts. Thus the satisfactory Bs is assured at this part and therefore the magnetic saturation can be prevented there.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a thin film magnetic head manufactured using thin film forming techniques such as CVD, photolithography, etching, and the like.

(Prior Art) As shown in FIG. 4, the general structure of a thin film magnetic head incorporated in a magnetic recording/reproducing device is that a gap 10 is formed between the tips of an upper core 100 and a lower core 101 by a nonmagnetic layer 102.
3 and is surrounded by an insulating layer 104 in the space where the upper core 100 and the lower core 101 face each other.
forming a pattern.

(Problem to be Solved by the Invention) Since the above-mentioned thin film magnetic head is manufactured using thin film forming techniques such as vacuum evaporation, sputtering, or CVD, the top core 100 has a flat tip 100a forming a gap and a flat rear part. The inclined portion 100c that is continuous with the portion 100b tends to be formed thinner than other portions. Therefore, in the magnetic circuit of the thin-film magnetic head, the part of the sloped part 100c becomes magnetically saturated first, and even if the thickness is the same, it is difficult for magnetic flux to flow through the sloped part 100c, making it difficult to guide all the magnetic flux to the vicinity of the gap. Can not. For this reason, the Bs of the magnetic film cannot be fully utilized, and a magnetic flux with a higher magnetic flux density than the gap cannot be emitted, resulting in disadvantages such as a decrease in recording efficiency and the inability to perform recording with a high coercive force medium head.

Furthermore, the inclined portion 100c has poor soft magnetic properties, resulting in a reduction in reproduction efficiency and sensitivity.

(Means for Solving the Problems) In order to solve the above problems, the present invention positions the front end of the flat part of the upper core of the magnetic head manufactured by thin film forming technology in front of the zero point of the magnetic gap life. Ta.

(Function) By locating the front end of the flat portion of the upper core ahead of the 0 point of life of the magnetic gap, the sloped portion of the upper core becomes thicker, and magnetic saturation in this portion can be prevented.

(Example) Embodiments of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 is a sectional view of a thin film magnetic head according to the present invention, and FIG. 2 is a plan view of the same thin film magnetic head.

The thin-film magnetic head is formed by forming insulating layers 2, 3, 4.5 on a substrate 1 using thin film forming techniques such as vapor deposition, sputtering, or CVD, and a portion of these insulating layers 2, 3, 4.5 is photo-photographed. A recess is formed by removal using lithography and dry etching, and a lower core 6, intermediate cores 7a and 7b made of a magnetic material mainly composed of Fe, Co, Ni, etc. are placed in the recess.
, an upper core 8 and a conductor coil 9 made of CuSAl, Au, Ag, etc. are buried therein, and the conductor coil 9 and the lead portion 10 are connected by a conductor 11 in the contact hole.

Further, a magnetic gap 12 is formed between the front intermediate core 7a and the lower core 6, and in the present invention, the rear end of the magnetic gap 12 in the depth direction, that is, the life 0 point (the life is zero) The front end P of the flat part 8a of the upper core 8 is positioned forward than the point where the flat part 8a of the upper core 8 becomes This allows us to make full use of the Bs in this area. In the illustrated example, the front end portion of the upper core 8 is cut out diagonally, but the front end of the flat portion 8a may be extended to a point P' shown by an imaginary line where the upper core 8 is cut out.

Next, an example of a method for manufacturing the thin film magnetic head of the present invention will be explained based on FIG.

That is, as shown in FIG. 3(a), the thin film magnetic head is manufactured using thin film forming technology such as 8102, T i O2 on the substrate 1.
Alternatively, the insulating layer 2 of Al2O3 or the like is formed to a thickness of 1 to 10 .mu.m, and then the insulating layer 2 is etched through a mask made by photolithography to form the core-shaped groove 13. Then, as shown in FIG. 13(b), a layer of soft magnetic material mainly composed of Fe, Co, and Ni is formed in the groove 13 using thin film formation technology, and the excess portion of the upper part of this magnetic layer is removed by polishing. The lower core 6 is obtained by removing the core and flattening the surface.

Next, as shown in the figure (C), another insulating layer 3 is formed on the insulating layer 2, and as shown in the figure (d), a coil groove 14 formed on the surface of the insulating layer 3 by etching is formed. A conductor such as Cu, Al, Au, or Ag is embedded using a thin film forming technique, and the excess portion on the conductor is removed by polishing to flatten the surface to form a conductor coil 9. Note that the depth of the coil groove 14 does not reach the lower core 6 to ensure electrical insulation.

After that, as shown in the same figure (e), the insulating layer 4 of 5102, TiO□, Al2O3, etc.
．． It is formed to a thickness of 1 to 1 μm, and grooves 15a and 15b of the intermediate core are formed at the front and rear by etching, as shown in FIG. 2(f). Here, the groove 15a of the front intermediate core is made into a tapered shape and the etching is stopped leaving a gear tooth portion, and the groove 15b of the rear is etched until the lower core 6 is exposed.

Next, as shown in the same figure (g), the groove 15a of the intermediate core,
15b by thin film formation technology.

A layer of a soft magnetic material containing Co and Ni as main components is formed, and an excess portion of the upper part of this magnetic layer is removed by polishing to flatten the surface to form intermediate cores 7a and 7b.

As shown in FIG. 5(h), an insulating layer 5 of 8102, TiO2, A1°03, etc. is formed using thin film forming technology.
is formed with a thickness of 1 to 10 μm, and the core groove 1 is formed in the same manner as above.
6 is etched, and a layer of soft magnetic material mainly composed of Fe, Co, and Ni is formed in the groove 16 as shown in FIG. The upper core 8 is obtained by removing the upper core 8 and flattening the surface.

After that, as shown in FIG. 12(j), a contact hole is formed in the insulating layer 5, the inside of this contact hole is filled with a conductor 11, and the conductor coil 9 is connected to the conductor coil 9 as described above through this conductor 11. A Cu layer having a thickness of 1 to 10 μm is formed, and this Cu layer is etched into a predetermined shape to form the lead portion 10.

Thereafter, the thin film magnetic head shown in FIG. 1 is obtained by cutting so that the magnetic gap 12 becomes the end.

(Effects) As explained above, according to the present invention, the front end of the flat part of the upper core of the magnetic head manufactured by thin film formation technology is positioned forward of the zero point of the magnetic gap life. The sloped portion of the core becomes thicker, and magnetic saturation of the sloped portion can be prevented. Therefore, the Bs of the magnetic film can be fully utilized, and recording efficiency, reproduction efficiency, and sensitivity can be improved.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a thin film magnetic head according to the present invention, FIG. 2 is a plan view of the same thin film magnetic head, and FIGS. 3(a) to (j)
4 is a diagram showing an example of a method for manufacturing a thin film magnetic head, and FIG. 4 is a sectional view of a conventional thin film magnetic head. 1... Substrate, 2, 3, 4.5... Insulating layer, 6...
Lower core, 7a, 7b...middle core, 8...upper core,
9... Conductor coil, 12... Gap, P... Front end of flat part of upper core.

Claims (1)

[Claims] In a thin film magnetic head in which a conductor coil is arranged between cores made of magnetic material via an insulator, and a magnetic gap is formed between the tips of the cores, the front end of the flat part of the upper core is connected to the front end of the flat part of the upper core of the core. A thin film magnetic head characterized in that it is located forward of the zero point of life dimension.