JPS58108017A - Thin-film magnetic head - Google Patents

Abstract

PURPOSE:To facilitate minute work and to increase a reproduction output by using polyimide resin for patterning the insulating layer of a magnetic head which has an upper magnetic body formed of a thin film on a lower magnetic material with an insulating layer between. CONSTITUTION:In resist 32 provided over an Mn-Zn ferrite substrate 31 as the lower magnetic body, a groove is formed by an etching solution of phosphoric acid and polyimide resin 33 as a nonmagnetic insulating material is applied therein to an about 10mum thickness; and resist 34 is formed over the groove. After the resin is etched by, for example, a hydrogen etching solution, the resist 34 is removed and a winding conductor 34 is vapor-deposited. After resist 35 in the same pattern as a wiring pattern is formed on the conductor 34, the conductor 34 is patterned by reactive sputter etching. Further, polyimide resin is applied to flatten the conductive wiring part and excessive resin is removed by resist 37. Then, an insulating film 38 for gap formation and permalloy 39 for an upper magnetic core are formed.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a thin film magnetic head with excellent recording and reproducing characteristics used in VTRs, magnetic disk drives, and the like.

In order to improve the recording and reproducing efficiency of a thin film magnetic head, it is necessary to reduce leakage of magnetic flux in the magnetic head winding. To achieve this, it is sufficient to increase the distance between the upper and lower magnetic cores in the winding section, and in the conventional magnetic head, the configuration shown in FIG. 1 is used. The head is formed by forming a ferromagnetic substrate 11K#1st such as ferrite, filling it with a non-magnetic insulating material 12t such as glass, polishing the surface flat, and forming a wire-wound conductor 13.K#1st such as ALI Cu or Au.
13'.

・Further S Todoroki 0. , At, O, etc., insulating layer 14,
It is manufactured by providing a magnetic thin film 15 of permalloy or the like (41!F 1982-118214). However, in an attempt to manufacture a large number of thin film magnetic heads on a large substrate by applying lithography technology in the semiconductor field, in the polishing process after filling the nonmagnetic insulating layer, the S depth of each head was adjusted to ±5 μm. It is extremely difficult to process uniformly within the accuracy of
As shown in FIG. 11, since the upper magnetic core 15 is not flat, there is a drawback that the head characteristics themselves are poor. moreover,
When an organic resin is used as the non-magnetic insulating layer, the difference in degree between the resin and the ferrite (11 degrees) is significant, and the ferrite part may sag due to polishing, making it necessary to strictly control the gap to about 5 μm. It is not possible to control the depth ga) in Figure 1, and the nonmagnetic insulating layer has no choice but to be filled with an inorganic insulator such as glass at a high temperature of about t-500R, and the head manufacturing process is also ineffective. It wasn't on point.

The invention is to solve the above problems by using organic resin such as polyimide as the non-magnetic filler and fabricating fine elements using only phosphorography technology, and to create a high-performance magnetic head with less variation in characteristics. This is something that is well provided. That is, the magnetic head according to the present invention is characterized in that a groove is formed in a nonmagnetic or ferromagnetic substrate, and the groove is filled with an organic resin such as a polyimide resin that wraps the AT excitation wiring conductor. It is.

The present invention will be described in detail below based on Examples.

FIG. 2 shows a thin film magnetic head according to the present invention formed on a Mn-7,n ferrite substrate 21 (which serves as the lower magnetic material). Here, 24 is a nonmagnetic gap forming layer, 2
5 is a permalloy magnetic layer (which becomes the upper magnetic body). The present magnetic head was manufactured by a method as shown in FIG. 3, an example of the process. First, a resist 32 is prepared on a ferrite substrate 31 and etched to a depth of 10 μm1 using a phosphoric acid etching solution.
After forming a groove with a length of 100 μm (FIG. 3(a)), a polyimide resin 33 is applied to a thickness of approximately 10 μm to form a resist 34 thereon (FIG. 3(a))). After etching the resin with a hydrazine etching solution, the resist is removed (FIG. 3(C)), and At34t is deposited to a thickness of approximately 2 μm. A
35t-
After the formation, At is patterned using reactive substrates and twigs (FIG. 4(d)).

Further, after applying a polyimide resin to flatten the conductor wiring portion (FIG. 3(e)), excess resin is removed using a resist 37. Similarly, gap forming insulation 1138,
Perm c+ (39t-) for the upper WilWB core can be formed ((f) and (g) in the same figure).

Another embodiment is shown in FIG. 41 is a ferrite substrate, 4
2 is a 5-iot gap forming layer, 43 is a polyimide resin, 44.44' is an AL wiring coil, and 45 is a permadi upper magnetic layer. The method for manufacturing this head is as follows.

After forming an MO mask layer 511 as shown in FIG. 5(a) on the substrate in the state shown in FIG. 3(C), a silicone resin 52 is etched approximately 5 μm by reactive sputter etching. Then, At53t-approximately 5 μm thick is deposited ((b) in the same figure).
After removing O together with O, as in FIGS. 3(e) to 3(g), a flat imide resin layer for flattening and a layer 5102 for gap formation are sequentially applied.
A permalloy layer for the upper magnetic core was formed.

Figure 6 shows the conventional head shown in Figure 1 and the second and fourth heads.
1 shows the characteristics of the head according to the invention shown in the figure. 61
, 62 and 63 are respectively the conventional head and the second . This is the self-recording/reproducing characteristic of the head of the present invention shown in FIG. However, for both heads, the number of windings, gap length, and track width are 8°0.5 μm and 30 μm, respectively, and the recording wavelength is 1
．． It is 4 μm. It is clear that the head according to the invention has better recording and reproducing characteristics than the conventional head. Further, the head shown in FIG. 4 has better characteristics than the head shown in FIG. 2 because the coil can be formed near the gap.

The above examples have shown examples in which a ferromagnetic material is used for the substrate, but permalloy, re-ht-s
By forming a magnetic thin film of i-based alloy, amorphous magnetic alloy, or the like as the lower magnetic layer, a head with excellent characteristics can be manufactured as in the above embodiment. However, when St- is introduced into the substrate through the process shown in FIG. 3 (1), fine irregularities occur on the surface of the grooves, and if a magnetic film is directly attached thereon, the magnetic properties will deteriorate significantly. It has been confirmed that the head characteristics are extremely poor due to the following.

FIG. 7 shows an embodiment according to the present invention that improves this drawback. In this head, a sieve formed on a magnetic substrate 71 is first molded with polyimide resin T-11 cloth approximately 5 μm thick, and then a permalloy thin film approximately 2 μm thick is deposited and molded as the lower magnetic layer by sputtering. Hereafter, the tubes were manufactured in the same manner as shown in FIG. 3 or 5.

The recording and reproducing characteristics of the head were similar to those shown in FIG. 6, 62 and 63.

In the above-mentioned head, it is clear that the organic resin is not limited to a bolide-based resin, but may also be a Si-based resin.

Furthermore, although this example shows a head with a single-layer winding structure,
In the case of a multi-layer head, the degree of improvement in performance compared to conventional heads is quite remarkable.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing the structure of a thin film magnetic head according to an example of the prior art (rear wiring, image retention layer, etc. are omitted, hereinafter referred to as "-"), and FIG. 2 is a thin film magnetic head according to an embodiment of the present invention. 3(a) to 3(g) are sectional views showing the manufacturing process of the magnetic head shown in FIG. 2, and FIG. 4 is a cross-sectional view showing a magnetic head according to another embodiment of the present invention. 5(a) and Φ) are schematic cross-sectional views showing the manufacturing process of the magnetic head shown in FIG. 4, and FIG. FIG. 7 is a cross-sectional view showing a thin film magnetic head in yet another embodiment. 21...M n -7, n ferrite substrate, 22...
・Polyimide resin, 23.23'...Wound conductor, 2
4...Nonmagnetic gap forming layer, 25...Permalloy magnetic layer, 61...For conventional thin film magnetic head, 62
．． 63... In the case of the thin film magnetic head in the embodiment of the present invention, 72... Polyimide resin, 73... Lower magnetic layer. Agent Patent Attorney Toshiyuki Usuda 41 Yz Diagram (L

Claims (1)

[Claims] 1. An upper magnetic body made of a thin film is provided on the lower magnetic body via an insulating layer, and a winding conductor layer is provided within the insulating layer,
In the magnetic head in which the lower magnetic body and the upper magnetic body are magnetically conductive at a portion opposite to the surface facing the magnetic recording medium, the insulating layer is made of an organic resin, and at least The lower part is a thin film magnetic head formed by filling nine grooves on the substrate. 2. The thin film magnetic head according to claim 1, wherein the organic resin is a polyide resin. 3. A thin film magnetic head according to claim 1 or 2, wherein the substrate is made of a ferromagnetic material. 4. Claim 1, characterized in that the substrate is a non-magnetic substrate having grooves to which an organic resin is adhered.
The thin film magnetic head according to item 1 or 2.