JPS61123009A - Multitrack thin film magnetic head and its production - Google Patents

Abstract

PURPOSE:To improve the output considerably by the constitution where tracks adjacent to each other in the front end part of a head are not in the same plane but alternate tracks form parallel planes. CONSTITUTION:Tracks adjacent to each other in the front end part of the head are not in the same plane, but alternate tracks form parallel planes. For example, the front end part of the head of a substrate 5 formed by sintering Al2O3 has a track part 6 whose section is a saw teeth shape, and tracks 6a and 6b adjacent to each other are not in the same plane but alternate tracks 6a or 6b form parallel planes. A width T of each track is 92mum, and its horizontal length is 80mum, and the angle of each track forming surface to the track arrangement direction, namely, an azimuth angle theta is 30 deg.. Thus, the crosstalk between adjacent tracks and the noise due to positional slippage for tape running are reduced. Therefore, the whole of the width of each track is used effectively, and as the result, the output is improved considerably.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a multi-track thin film magnetic head for magnetic recording and reproduction of digital signals in audio tape recorders and the like.

BACKGROUND OF THE INVENTION In contrast to conventional ring-type heads, thin-film magnetic heads are being developed that utilize fine pattern technology in the semiconductor field. Thin-film magnetic heads enable multi-tracking with fine patterns and are suitable for high-density recording, and in recent years have been used to record digital signals.

It is attracting attention as a material for reproduction.

A conventional thin film magnetic head will be described below with reference to FIG. (For example, Special Publication No. 57-16409
12(a) is a perspective view of a conventional thin film magnetic head.
FIG. 2 (l is a recording/reproducing pattern diagram.

In FIG. 12, 1 is a multi-track thin film magnetic head, 2 is an effective track portion of a recording or reproducing head, and each track is formed on the same plane and is aligned in a straight line on the tape sliding surface.

3 is a recording pattern of the multi-track thin film magnetic head 1;
4 is a playback pattern.

T is the distance between tracks, 80 μm, T2 is the recording width, 65 μm, and 1T3 is a guard band that is provided at a certain distance to prevent crosstalk from adjacent tracks and noise caused by tape misalignment. is 3011 m, and T4 is the reproduction width, which is 5Q μm.

Problems to be Solved by the Invention However, in the above-mentioned conventional configuration, there are 8
Although it is possible to use 0μm, in reality it is about 60% of 50μm.
Only .mu.m is used, and as a result, the output level is approximately 4 dB lower than when using full-width tracks.

As described above, conventional linearly arranged heads require a guard band to prevent noise from occurring due to crosstalk or positional deviation during tape running, which has the problem of lowering the output.

Furthermore, in the structure of the head, in conventional magnetoresistive read heads, it is necessary to apply a bias magnetic field to the magnetoresistive element (hereinafter referred to as MR element) to tilt the direction of anisotropy to the optimum operating point. Therefore, there was a problem in that a bias line had to be formed.

The present invention was made in view of the above-mentioned problems, and it allows azimuth recording by creating an angle (azimuth angle) between adjacent tracks.
Playback prevents crosstalk with adjacent troughs and noise caused by tape position shift during tape running, and also allows each track to utilize the given track width to its fullest, thereby significantly increasing the output. The purpose is to improve.

Means for Solving the Problems In the present invention, adjacent tracks at the tip of the head are not on the same plane, but every other track forms parallel planes.

Effects With the above-described configuration, the present invention performs azimuth recording and playback with an angle between tracks, thereby preventing crosstalk with adjacent tracks and the generation of noise due to tape position deviation during tape running, and reducing the track width to the full width. It can be used to significantly improve output.

EXAMPLE An example of the present invention will be described below with reference to FIGS. 1 to 11.

FIG. 1 is a perspective view of a substrate of a reproducing head in a multi-travel six-beak thin film magnetic head according to an embodiment of the present invention;
FIG. 2a is a top view thereof, and FIG. 2a is a side view thereof.

In FIGS. 1 and 2, reference numeral 6 denotes a substrate formed by sintering Al2O3, and the head tip of the substrate 5 has a track portion 6 with a sawtooth cross section, and adjacent tracks 6a , 6b on the same plane, every other track 6
a or 6b are parallel planes. The width T of each track is 92 μm, the horizontal distance thereof is 80 μm, and the angle formed by each track forming surface with respect to the rack arrangement direction, that is, the azimuth angle θ, is 3o0.

Next, the manufacturing process of a multi-track thin film magnetic head using the substrate 5 will be explained with reference to FIGS. 3 to 1. Note that FIGS. 3 to 10 are enlarged views of the head tip portion of FIG. 2.

In FIG. 3, 7 is a metal mask made of non-magnetic stainless steel, and 8 is a slit for forming a magnetoresistive element (hereinafter referred to as MR element) by vapor-depositing permalloy.

7 Vane Here, first, using a metal mask on the substrate 6,
(81% by weight) - Fe (19% by weight) permalloy
Vapor deposition is performed while applying a magnetic field in the same direction as shown in FIG. 4, to form an MR element 9 with a film thickness of 0.06 μm.

Next, on the substrate 5'' on which the MR element 9 has been formed, Au/Cr lead wires 10 are formed using a metal mask 7 as shown in FIG. An insulating layer 11 of S.02 with a thickness of 0.3 μm is formed as a gap.

Furthermore, as the flux guide 12, Ni-Zn ferrite is formed by mask sputtering as shown in FIG.
The lower end is cut by dicing to form a polished part 13 and a cut part 14 as shown in FIGS. 8a and 8b. Teeth, the first month of the year, 1 love and 0 years ago) 4th place in the country.

As a result, each track is separated by a cutting width of 15 μm. The separation width is preferably as narrow as possible in terms of output, and is preferably 16 μm or less.

Next, as a protective layer 16, SiO2 is formed by sputtering up to the vicinity of the upper end of the substrate 5, as shown in FIG. There is. A suitable material for the protective substrate 16 is a ceramic sintered body.

At this time, the distance between the MR element 9 and the tip is read in advance, and after bonding the Mn-Zn ferrite, the predetermined M
The tip was wrapped to the width of the R element. Next, I made the housing and connected the flexible wire. A reproducing head formed in this manner is shown in FIG. The flow of magnetic flux in this head passes through the tape, the MR element, the Ni--Zn ferrite film, and returns to the tape.

The recording head also uses a metal mask 7, the coil part is made of aluminum with two layers and two turns, and the yoke is made of Ni-
Manufactured using Fe permalloy.

When the recording/reproducing head of the present invention is used, an improvement of about 4 dB at the same frequency is observed compared to the case of using a conventional planar head with the same inter-track distance and the same head configuration, and the S/N ratio is also about 3 dB. Improved.

9 Vane Also, a characteristic diagram showing the relationship between the azimuth angle and the uniaxial anisotropy constant Ku, which is the magnitude of shape anisotropy, is shown in FIG.

As shown in Fig. 11, in this example, the azimuth angle is 20°.
Above and below 60 degrees, expression of large anisotropy to the extent that no bias magnetic field is required is observed.

This is because the self-shading effect creates a columnar structure that is connected in a chain in a direction 900 degrees relative to the incident direction and is tilted obliquely. For this reason, a suitable azimuth angle is 20° or more and 6o0 or less.

Effects of the Invention In the present invention, since adjacent tracks in the head are not on the same plane, and every other track is on a parallel plane,
Noise '(r) due to crosstalk between adjacent tracks and positional deviation during tape running can be reduced.

Therefore, the entire width of each track can be used effectively.
Output can be significantly improved.

In terms of the structure of the read head, since each track surface is inclined, shape anisotropy naturally occurs in the MR element, there is no need to apply a 1Q peno bias magnetic field, and there is an advantage that the structure is simple.

Further, since the MR element and the flux guide are once formed in a single stripe shape spanning all the tracks, and then separated for each track in a subsequent process, lateral precision is no longer required.

Similarly, the Au/Cr lead wire does not require lateral precision because it is separated into tracks in a later process. Note that the present invention is effective not only for longitudinal recording but also for perpendicular recording.

[Brief explanation of drawings]

FIG. 1 is a perspective view of the substrate of a multi-track thin film magnetic head in an embodiment of the present invention, FIG. 2 a is a characteristic diagram showing the relationship with the axial anisotropy constant, and FIG. 12 a is a conventional thin film magnetic head. FIG. 12 is a perspective view of the head and a recording/reproduction pattern diagram. 5...Substrate, 6. ...Truck club, 6
a, 6b, -11 p-7... Track, 9... Magnetoresistive element, 1
0... Lead wire, 11... Insulating layer, 12
... Flux guide, 13 ... Polishing section,
14... Cutting portion, 15... Protective layer, 1
6...Protection board. Name of agent: Patent attorney Toshio Nakao and 1 other senior citizen
-- Figure 8 Figure M9 Figure 11

Claims (7)

[Claims] (1) A multi-track thin film magnetic head characterized in that adjacent tracks at the tip of the head are not on the same plane, and every other track forms a parallel plane. (2) A multi-track thin film magnetic head according to claim 1, wherein the substrate is a ceramic sintered body having a sawtooth-like unevenness on the thin film forming surface at least near the tape sliding portion of the head. (3) The multi-track thin film magnetic head according to claim 1, wherein the angle formed by each track forming surface with respect to the track arrangement direction is 20° or more and 60° or less. (4) The multi-track thin film magnetic head according to claim 1, wherein the separation width between each track is 15 μm or less. (5) A method for manufacturing a multi-track thin-film magnetic head in which adjacent tracks are not on the same plane, the substrate has a substrate in which every other track is a parallel plane, and the lead wires of the adjacent tracks are formed by a single lead wire. (6) A method of manufacturing a multi-track thin film magnetic head according to claim 5, wherein after forming one lead wire, cutting between each track is performed to form a magnetoresistive element and a flux guide. (7) After forming one lead wire, the track tip is separated into two lead wires by cutting or polishing, thereby forming a lead wire for each track. A method for manufacturing a track thin film magnetic head.