JPS63153707A - Thin film magnetic head - Google Patents

Abstract

PURPOSE:To improve the crosstalk characteristic at both ends of poles and to provide a high track density by disposing the upper pole to confront the lower pole over the entire effective length of the lower pole via a nonmagnetic material in the case of using the upper and lower poles to constitute the magnetic gap of a magnetic head for magnetic recording and reproducing. CONSTITUTION:The lower pole 3 consisting of an NiFe alloy is formed to an underlying layer 2 existing on a ceramic substrate 1. The surface 3a and both side faces 3b of the pole 3 are then enclosed by the nonmagnetic material 4 such as Al2O3 and further stagnating parts 3c are formed to both ends thereof. The surface thereof is coated with the U-shaped upper pole 5 and an over coating layer 6. The upper pole 5 confronts the lower pole 3 over the entire effective length thereof including the end part if the magnetic head is constituted in the above-mentioned manner. As a result, leakage magnetic fluxes in the direction perpendicular to the progressing direction of tracks are extremely decreased and the crosstalk characteristic is improved. The high track density is thus easily attained.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a magnetic head used in a magnetic recording/reproducing device, and in particular to a narrow track thin film magnetic head with little talostoke.

[Prior art 1] Conventionally, as shown in FIG. 2, in this type of thin film magnetic head, an upper pole 5 is constructed above a lower ball 3 with a gap layer 4 forming a gap interposed therebetween. length! 1 is the length I of the lower pole 3! It is set shorter than 2. This is because a tolerance for misalignment between the two poles is taken into consideration. In the figure, 1 is a substrate, 2 is a base layer, and 6 is an overcoat layer.

[Problems to be Solved by the Invention] However, in terms of the mechanism of magnetic recording and reproducing, extremely large recording is performed by the upper and lower poles 3 and 5 at both ends of the lower pole 3, in the portions that do not face the upper pole 5. This means that a regeneration gap has been formed.

This pseudo gap has a serious drawback in that it affects the signals of adjacent tracks and causes deterioration of so-called crosstalk characteristics. In such a conventional thin film head, in order to improve the Talostoke characteristic, it is necessary to
It was necessary to provide a guard band area as large as 0 microns, and it was not possible to increase the track density even though the head had a narrow track.

SUMMARY OF THE INVENTION An object of the present invention is to provide a narrow track, high track density magnetic recording device having a new pole groove structure that eliminates the effects of the pseudo gap at both ends of the pole of a conventional head.

[Means for Solving the Problems] The present invention has a first pole and a second pole constituting a magnetic gap for performing magnetic recording and reproduction, and the second pole is connected to the effective length range of the first pole. The thin film magnetic head is characterized in that the first pole is opposed to the first pole through a nonmagnetic material.

[Example] Next, an example of the present invention will be described with reference to the drawings.

FIG. 1 shows an embodiment of the present invention, showing the air bearing surface of a magnetic head cap portion as viewed from the medium surface side.

In FIG. 1, reference numeral 1 denotes a substrate, that is, a ceramic slider, on which a base layer 2 is formed.
A first pole 3 made of NiFe alloy is formed thereon. On the surface of the first pole 3 is AI! A gap layer 4 made of a non-magnetic material such as 203 is formed. The gap layer 4 is formed to surround the surface of the first pole 3, that is, the top surface 3a and both side surfaces 3b, and in particular, at both ends of the first pole 3, the corner portions have slightly concave portions 3C as shown in the figure. It becomes. A second pole 5 is formed on the gap layer 4, and the upper pole 5 is extended into a U-shape so as to cover the lower ball 3 including its end. The first pole 3 and the second pole 5 can also be formed by either sputtering or plating. After forming the second pole, an overcoat layer 6 is formed.

According to the present invention, since the upper pole 5 is extended to cover the lower pole 3 including its end, the upper pole 5 is non-magnetic with the lower pole 3 over the effective length range of the lower ball 3. They face each other with the gap layer 4 in between. As a result, a gap is formed between the end of the lower ball and the upper pole in parallel to the track running direction, and therefore a leakage magnetic field in the direction perpendicular to the track running direction is generated only in the very vicinity of both sides of the lower ball. Magnetic fields have no effect on reading or writing information.

[Effects of the Invention] As explained above, in the first and second poles forming a gap, the second pole faces the first pole via the non-magnetic gap also at both ends of the first pole. Therefore, the area in which a leakage magnetic field occurs in the direction perpendicular to the track longitudinal direction is extremely small and has no effect on adjacent track information.

Therefore, it has an extremely good Talostok characteristic and has the effect of easily achieving high track density.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of the present invention, and FIG. 2 is a block diagram showing a conventional example.

Claims (1)

[Claims] (1) The first part that constitutes the magnetic gap that performs magnetic recording and reproduction.
and a second pole, the second pole facing the first pole across the effective length range of the first pole via a nonmagnetic material. magnetic head.