JPS59231717A - Vertical recording head - Google Patents

Abstract

PURPOSE:To increase the magnetic resistance to prevent saturation of a recording medium of high permeability which is due to the magnetic flux generated from a substrate and to improve the recording efficiency, by using a nonmagnetic insulated material to form the area near the end face of the substrate corresponding to the recording medium. CONSTITUTION:A nonmagnetic insulated material 10 is used to form the area close to the face opposite to a recording medium 6 for a substrate 11 made of a ferromagnetic material 9, and a spiral coil layer 3 is formed on the material 10. Then a main magnetic pole layer 14 consisting of a ferromagnetic thin film is provided on the layer 3. The magnetic flux generated by a signal current flowing to the layer 3 passes a magnetic path of the layer 14 a vertical anisotropic medium 4 a medium 8 of high permeability the material 10 the material 9 the layer 14. Thus the medium 4 set under a ''Permalloy'' film 12 of the layer 14 is intensively magnetized. Thus the saturation is eliminated for the medium 8 of the medium 6 due to the magnetic flux generated from the substrate 11. At the same time, the saturation of the layer 14 is also suppressed. This ensures the intensive magnetization up to the tip of the main magnetic pole and improves the recording quality.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application This invention relates to an efficient perpendicular recording head used in perpendicular magnetic recording.

Conventional structure and its problems As a perpendicular recording head capable of recording from one side of a recording medium, conventionally a groove filled with a non-magnetic material 7 is formed in a part of a ferromagnetic substrate 2 as shown in FIG. Coil layer 3 is formed on top of the coil layer 3.
A structure has been proposed in which the main magnetic pole/i1 is formed of a ferromagnetic thin film. Reference numeral 6 denotes a recording medium, consisting of a vertically anisotropic medium 4 and a base film 5. The operation of this perpendicular recording head is such that when a signal current is passed through the coil layer 3, a signal magnetic flux flows from the main pole layer 1 to the perpendicular anisotropic medium 4, magnetizes it, and returns to the ferromagnetic substrate 2. In this case, since the magnetic resistance of the magnetic path of the signal magnetic flux is large in the single layer film of the perpendicular anisotropic medium 4, it is desirable that the substrate 2 has a shape with as little magnetic resistance as possible. In the case of a two-layer film consisting of the high magnetic permeability medium 8 and the perpendicular anisotropic medium 4, the high magnetic permeability medium 8 may be saturated by the magnetic flux from the ferromagnetic substrate 2 side, resulting in poor recording efficiency. In particular, if the recording medium is 0.2μ like tape,
In the case of a magnetic layer thickness of approximately m thickness, the recording efficiency decreases significantly. In FIG. 1, the main pole layer 1 and the coil layer 3 are shown floating above the substrate 2, but in reality, an insulating layer is interposed in the gap.

OBJECTS OF THE INVENTION An object of the present invention is to provide a perpendicular recording head that can completely prevent saturation of a high magnetic permeability recording medium and improve recording efficiency.

Structure of the Invention The perpendicular recording head of the present invention includes a substrate in which the vicinity of the end face facing the recording medium is made of a non-magnetic insulating material and the part remote from the vicinity of the end face facing the recording medium is made of a ferromagnetic material; and this substrate. a spiral coil layer attached to the side surface of the substrate so that its center faces the ferromagnetic VL material; a main magnetic pole layer that extends across the shaped coil/I/N to the end surface facing the recording medium, and a portion of the main magnetic pole layer near the end surface facing the recording medium is thinned, and the main magnetic pole layer It is characterized by having a thicker part away from the vicinity of the end face facing the recording medium.

With this configuration, the part of the main pole layer away from the end face (the upper part of the coil) is thicker than the part near the end face of the main pole layer, so the efficiency of the magnetic flux passing through the main pole layer is good, and the substrate Since the side has an appropriate magnetic resistance, the high magnetic permeability medium of the recording medium is not saturated with the magnetic flux flowing into the recording medium from the substrate side, and highly efficient recording can be performed.

DESCRIPTION OF EMBODIMENTS An embodiment of the present invention will be described below based on FIGS. 3 to 6.
'('Explain. In Fig. 3, Mn-Zn and Ni-
The substrate 11 made of a ferromagnetic material 9 such as Zn ferrite has a portion near the surface facing the recording medium of 5io2 or At203. It is made of a non-magnetic insulating material 10 such as crystallized glass. A spiral coil layer 3 made of Arl+At, Cu, etc. is formed thereon by an ordinary thin film process via an insulating material (not shown) such as StO2. Furthermore, a main pole layer 14 made of a ferromagnetic thin film is formed thereon via an insulating material (not shown). This main pole layer 14 is made of, for example, a vapor-deposited permalloy film 12 with a thickness of 0.5 μm, a permalloy film 13 with a skin thickness of 3 μm plated thereon, and a substrate 2.
It's thinner.

A cover glass is then glued in a conventional manner to form a perpendicular recording head.

The operation of this perpendicular recording head will be explained based on FIG. 4.

15 is an insulating film. The magnetic flux generated by the signal current flowing through the coil M3 is directed from the main pole layer 14 to the arrow shown in the figure.
The perpendicular anisotropic medium passes through a magnetic path consisting of the perpendicular anisotropic medium 4 - high magnetic permeability medium 8 -> non-magnetic material 10 -> ferromagnetic material 9 -> main magnetic pole layer 14 , and forms the vertical anisotropic medium under the permalloy film 12 of the main magnetic pole layer 14 4 is strongly magnetized. In this case, the C0-Cr vertical anisotropic medium layer 70
0A.

The input/output characteristics when recorded and reproduced on a recording medium 6 with a permalloy high magnetic permeability film thickness of 1000 people are as shown by the 5N curve (al). is used, the high magnetic permeability medium of the recording medium 6 (
The permalloy layer) 8 becomes saturated and the recording efficiency decreases, resulting in a characteristic like the curve (bl) in FIG. Because the magnetic pole layer 14 is saturated, the tip of the main magnetic pole layer 14 is not sufficiently magnetized, and recording is not possible until the perpendicular anisotropic medium 4 is saturated, as shown by the curve (cl) in FIG. allows saturation recording with a small magnetomotive force on the thin recording medium 6. Regarding the thickness of the tip of the main pole layer 14 and the top of the coil, the ratio (coil top thickness/tip thickness) shown in FIG. As can be seen from the results of the head where (ml is 6, (b) is 2, and (C1 is 1), if the thickness ratio is doubled or more, it is possible to record almost fully to saturation.

As described above, in the perpendicular recording head of this embodiment, the recording medium sliding surface of the substrate 11 is made of the non-magnetic insulating material 10, thereby increasing the magnetic resistance and causing magnetic flux from the substrate 11 side to increase. The saturation of the high magnetic permeability medium 8 of the recording medium 6 is eliminated, and the thickness of the main magnetic pole is made thicker at the top of the coil to make it difficult for the main magnetic pole layer 14 to saturate, making it possible to strongly magnetize up to the tip of the main magnetic pole, thereby increasing the overall magnetic path. This prevents a decrease in the recording magnetic field due to an increase in magnetic resistance, making it possible to record with good characteristics.

In this embodiment, an example of a combination of permalloy is shown as the main pole layer 14, but good results can also be obtained by using sendust or an amorphous ferromagnetic thin film.

In addition, in the perpendicular recording head of this structure, since the ferromagnetic material 9 on the substrate 11 side does not directly contact the recording medium 6, unnecessary signals are not recorded on the recording medium 6 on the substrate 11 side, and noise is prevented. Less recording is possible.

The thickness of the non-magnetic insulating material 10 of the substrate 11 varies depending on the thickness of the main pole and the thickness of the recording medium, but is 10 μm to 200 μm.
Effects of the Invention According to the present invention, a perpendicular recording head capable of efficiently recording from one side of a perpendicular recording medium can be obtained. Furthermore, since it can be manufactured in the same process as conventional thin film recording heads, it is easy to make multi-track recording heads.

[Brief explanation of the drawing]

Fig. 1 is a side view of a conventional perpendicular recording head, Fig. 2 is a side view of a recording medium, Fig. 3 is a perspective view of an embodiment of the present invention, Fig. 4 is a sectional view, and Fig. 5 is a side view of a recording medium. FIG. 6 is a characteristic diagram showing the difference in characteristics between the head of the example and other structures. FIG. 6 is a characteristic diagram showing the difference in characteristics due to the difference in the thickness of the main pole layer in the example. 6...Recording medium, 9...Ferromagnetic material, 10...Nonmagnetic insulating material, 11...Substrate, 12.13...Permalloy film, 14...Main pole layer 1st circle Figure 2: 3r: 5 Figure 4: Magnetomotive force (Nl) - Figure 5 - Figure 6

Claims (2)

[Claims] (1) A substrate in which the vicinity of the end face facing the recording medium is formed of a non-magnetic insulating material and the part remote from the vicinity of the end face facing the recording medium is formed of a ferromagnetic material, and the side surface of this substrate has its own center a spiral coil layer attached to face the ferromagnetic material; a spiral coil layer formed thinner than the substrate, with a base end located at the center of the spiral coil layer and a tip end crossing the spiral coil layer to reach the recording medium; a main magnetic pole layer extending to opposing end surfaces, a portion of the main magnetic pole layer near the end surface facing the recording medium is thinned, and a portion of the main magnetic pole layer farther away from the vicinity of the end surface facing the recording medium is thinned. Thickened vertical recording head. (2) The perpendicular recording head according to claim (1), wherein the thickness of the part of the main pole layer separated near the \φ end is at least twice the thickness of the part near the end face. .