KR19990018093A - Magnetic head and its manufacturing method - Google Patents

Abstract

In manufacturing a magnetic head for MIG type magnetic recording and reproducing, in which a magnetic metal film is formed in a gap region where a pair of manganese-zinc (Mn-Zn) ferrite single crystal core halves come into contact with each other, a track of the gap region is formed through an etching process using a photoresist. The magnetic head is enhanced to cope with high-density digital magnetic recording and reproducing systems by improving the recording density by suppressing leakage of magnetic signals, by securing the track width region by the method of forming the metal magnetic film to be limited to only the region corresponding to the width. And a method of manufacturing the same.

Description

Magnetic Head and Manufacturing Method Thereof

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic head used for video and audio recording and reproduction of a magnetic recording reproduction system such as a video tape recorder (VTR), and a method of manufacturing the same. In particular, a metal-in-gap that can cope with a high density digital recording reproduction system. (MIG; Metal-in-gap) type magnetic head and a manufacturing method thereof.

The magnetic head is used for recording information on a magnetic recording medium such as a magnetic tape or a magnetic disk, or for reproducing the recorded information. For example, when the front end surface of the magnetic head touches a magnetic tape used as a recording and reproducing medium of a VTR, Information is recorded and / or reproduced. In recent years, magnetic recording / reproducing methods using magnetic heads have been increasingly used as digital methods capable of recording and / or reproducing a large amount of information two to four times larger than analog methods. With such a trend, there is an increasing demand for high density recording in order to record a large amount of information within a limited range of magnetic recording media. To meet these demands, metal-in-gap (MIG) or metal-laminates using magnetic materials that reduce eddy current loss at high frequencies and have better magnetic properties than ferrite Research on (ML) type magnetic heads is actively underway. In the case of the MIG magnetic head, since the leakage magnetic flux used to magnetize the magnetic tape leaks toward the magnetic tape, the amount thereof is reduced, so that the gap region is easily saturated and the recording efficiency is lowered. In particular, in the digital method, when the track width of the magnetic head is not defined accurately, not only the signal noise ratio but also the signal quality may be seriously degraded due to the lack of signal data.

FIG. 1 shows a MIG type magnetic head applied to a conventional analog VTR, and has a metal magnetic film 13 formed at a gap g region where a pair of core bodies 11 and 12 abut each other. 2, the head gap corresponding to the track width T by the signal generator 17 connected to the coil 16 wound on the winding groove 15 by contacting the magnetic tape 10 with the magnetic tape 10. Through (g), the magnetic signal can be recorded / reproduced. Manganese-zinc (Mn-Zn) ferrite single crystal is used as the material of the core halves 11 and 12, and is bonded by fused glass 14. The metal magnetic film 13 is formed of sputter deposition, mainly a sender alloy, permalloy alloy, iron nitride, or the like having a high saturation magnetic flux density and low coercive force.

FIG. 3 is a planar view of the magnetic tape contact surface of the magnetic head, and track width edge metal characters generated during processing such as the angle (θ) where the tracks of the magnetic head meet and the track shift (8) and heat treatment during recording and playback. Undesired magnetic signals are leaked at the edge of the track width T due to the corrosion 9 of the film formation and the like. Due to the leakage signal, recording / reproducing operations are performed for track areas other than the recording / reproducing track area of magnetic tape, so that the signal noise ratio of the recording / reproducing system is deteriorated due to cross talk noise, for example, digital. In the case of a signal, degradation of a bit error rate (BER) characteristic due to tracking error is caused. Accordingly, there is a problem in that the erasing characteristic of the magnetic signal due to the leakage signal and the erase characteristic due to overwrite are degraded during the recording / reproducing operation of the magnetic head.

The technical problem to be achieved by the present invention is to improve the problems of the conventional magnetic head described above, and an object of the present invention is to secure a precise track width and to increase the responsiveness to a high density digital recording and reproduction system. The present invention provides a gap magnetic head (MIG) and a method of manufacturing the same.

1 is a schematic perspective view showing a conventional magnetic head for reproducing metal-in-gap (MIG) type magnetic recording;

FIG. 2 is a schematic perspective view for explaining an operation relationship between the magnetic head and the magnetic tape shown in FIG. 1;

3 is a schematic plan view showing a magnetic tape contact surface of the magnetic head shown in FIG.

4 is a schematic perspective view showing a magnetic head for metal-in-gap (MIG) type magnetic recording reproduction according to the present invention;

5 to 12 is a step-by-step manufacturing process of the magnetic head according to the present invention.

Explanation of symbols for the main parts of the drawings

110, 120 ... Manganese-zinc single crystal core half 111, 121 ... Coil winding groove

112, 112 '... groove 113, 114 ... projection

130 Magnetic metal film 131 Insulation film (SiO ₂ film)

140 Molded glass 150 Coil winding groove

G ... Magnetic Head Gap T ... Track Width

In order to achieve the above object, the magnetic head according to the present invention is a magnetic recording and reproducing magnetic head in which a metal magnetic film and an insulating film are formed at a gap portion where a pair of manganese-zinc (Mn-Zn) ferrite single crystal core half abuts. The metal magnetic layer and the insulating layer may be formed to be limited only to a region corresponding to the track width of the gap portion, and the molding glass may be fused and filled to gap portions on both sides of the metal magnetic layer.

According to the magnetic head for magnetic recording reproduction according to the present invention, it is preferable that grooves are formed on the side and bottom of the groove along the joining line formed by the core half body, and the groove is filled with molded glass.

In order to achieve the above object, a method of manufacturing a magnetic head for magnetic recording reproduction according to the present invention includes a groove for coil winding on one surface of a manganese-zinc (Mn-Zn) ferrite single crystal block, and a plurality of grooves for fusion molding glass. A first step of processing; A second step of forming a core block body by depositing a metal magnetic film and an insulating film for forming a gap on the metal magnetic film on a protruding surface protruding around grooves and grooves of the block body which have passed the first step; A third step of joining the pair of core block bodies formed by the second step such that the insulating films are in contact with each other, and forming grooves for fusion of molding glass along the joints of the bottom surface; A fourth step of discontinuously applying the photoresist in the length direction of the metal magnetic film and the insulating film exposed to the upper surface of the junction of the pair of core block bodies by the length of the track width region to be formed; A fifth step of removing the magnetic metal film and the insulating film corresponding to a region other than the photoresist to a gap depth; A sixth step of removing the photoresist and fusing the molding glass to the upper portion of the coil winding groove formed through the center of the pair of core block bodies and the groove of the bottom surface formed in the third step; And a seventh step of cutting the pair of core block bodies so as to pass through a central portion of a circular conduit formed by a plurality of grooves abutting on the inner wall of the junction portion.

According to the present invention, the magnetic metal film is any one selected from sender, permalloy, Fe-N-based microcrystalline alloy, and the insulating film is any one selected from SiO ₂ , Al ₂ O ₃ is formed by a sputtering deposition process.

Hereinafter, with reference to the accompanying drawings will be described in detail a magnetic head for reproducing magnetic recording according to a preferred embodiment of the present invention and a method of manufacturing the same.

Referring to FIG. 4, in the metal-in-gap (MIG) type magnetic head according to the present invention, a gap G formed by a pair of manganese-zinc (Mn-Zn) ferrite single crystal core bodies 110 and 120 is in contact with each other. ), The magnetic metal film 130 is formed so as to be limited only to the region corresponding to the track width T, and the gap G portions (regions other than the track width) of the magnetic metal film 130 are etched. After finely removed by the molding glass 140 is fused and filled. The coils 160 are wound around the coil winding grooves 150 formed such that the grooves 111 and 121 formed at both sides of the core half bodies 110 and 120 abut against each other to form a through hole in the center portion. In addition, grooves (not shown) are formed on side and bottom surfaces of the core halves 110 and 120, and molding glass 140 is fused and filled in the grooves.

According to the present invention, the magnetic metal film 130 may be selected from sendust, permalloy, Fe-N-based microcrystalline alloy, and the permalloy alloy may be any one selected from FeRuGaSi and FeIrGaSi. The insulating film is preferably selected from SiO ₂ and Al ₂ O ₃ weightings.

The manufacturing method of the magnetic recording and reproducing magnetic head according to the present invention having the above configuration will be described in detail with reference to the step-by-step manufacturing process diagrams shown in Figs.

First, referring to FIG. 5, a coil winding groove 111 is formed on one surface of a manganese-zinc (Mn-Zn) single crystal ferrite block body 110 in a width direction, and a predetermined radius is perpendicular to the groove 111. Many grooves 112 are formed by processing. By such a process, protrusions 113 and 114 which protrude relatively are formed around the coil winding groove 111 and the groove 112, and the width t of the protrusion 113 is the tip of the manufactured magnetic head. It is formed larger than the track width T of the gap G formed in the gap.

Next, as shown in FIG. 6, a magnetic metal film 130, such as sendust, permalloy or iron nitride, is deposited on the upper surfaces of the protrusions 113 and 114 by sputtering. As described above, the SiO ₂ film 131 is formed on the upper surface of the magnetic metal film 130 to form a head gap, thereby completing the core block body. The metal magnetic layer 130 may be formed of a material as described above.

Another core block body 120 is manufactured in the same manner as the fabrication process of the core block body 110 completed as described above, and then the SiO ₂ film 131 is in contact with each other as shown in FIG. 8. The pair of core block bodies 110 and 120 are bonded to each other, and grooves 112 ′ for fusion molding of the glass are formed along the longitudinal direction of the junction of the bottom surface. Subsequently, a photo is formed by the length of the track width T to be formed on the exposed metal magnetic film 130 and the SiO ₂ film 131 along the longitudinal direction of the upper junction of the pair of core block bodies 110 and 120. By discontinuously applying the resistor P, a portion of the magnetic metal film 130 and the SiO ₂ film 131 is removed from the head gap G as shown in FIG. 9 by reactive ion etching. Remove to depth.

Subsequently, as shown in FIG. 10, the photoresist P is removed, and the upper end of the through hole 150 formed by the coil winding grooves 111 and 121 abuts with each other and the groove 112 ′, respectively. After the bar-shaped molding glass 140 is inserted, it is fused by heat treatment.

Finally, the pair of core block bodies 110 and 120 joined by the fusion of the molding glass 140 as described above is cut along the cutting line C-C 'shown in FIG. The cutting line C passes through the central portion of the circular conduit formed by a plurality of grooves 112 positioned on the inner wall of the junction of the pair of core block bodies 110 and 120, and after cutting, FIG. 12. As shown in FIG. 4, the unit magnetic head is manufactured, and the unit magnetic head is manufactured by the completed magnetic head through the curved surface processing and the coil winding process of the front end surface as shown in FIG.

As described above, according to the magnetic head and the manufacturing method thereof, the metal magnetic film is limited to only the region corresponding to the track width of the gap region through an etching process using a photoresist in the manufacturing process, thereby providing a precise track width. It can be easily secured. Therefore, the production yield can be increased, and magnetic signal leakage at the track width edge can be minimized, for example, the recording density is improved by, for example, cross talk noise reduction, tracking error, and overwrite performance improvement. Therefore, in particular, the ability to respond to a high density digital recording and reproduction system can be enhanced.

Claims (10)

A magnetic recording and reproducing magnetic head in which a magnetic metal film and an insulating film are formed in a gap region where a pair of manganese-zinc (Mn-Zn) ferrite single crystal core half abuts, wherein the metal magnetic film and the insulating film have a track width of the gap region. The magnetic head for magnetic recording and reproducing is formed so as to be limited to a region corresponding to the metal magnetic film, and a molding glass is fused and filled in gap portions on both sides of the magnetic metal film. 2. The magnetic head for magnetic recording and reproduction according to claim 1, wherein grooves are formed on side surfaces and bottom surfaces of the cores in contact with the core half body, and molded grooves are fused and filled with the grooves. The method of claim 1, And the metal magnetic film is formed of any one selected from sendust, permalloy, and Fe-N-based microcrystalline alloys. The method of claim 3, The permalloy alloy is any one selected from among FeRuGaSi and FeIrGaSi. The magnetic head for magnetic recording reproduction according to claim 1, wherein the insulating film is any one selected from SiO ₂ and Al ₂ O ₃ . A first step of processing grooves for coil winding and a plurality of grooves for fusion molding glass on one surface of a manganese-zinc (Mn-Zn) ferrite single crystal block body; A second step of forming a core block body by depositing a metal magnetic film and an insulating film for forming a gap on the metal magnetic film on a protruding surface protruding around grooves and grooves of the block body which have passed the first step; A third step of joining the pair of core block bodies formed by the second step such that the insulating films are in contact with each other, and forming grooves for fusion of molding glass along the joints of the bottom surface; A fourth step of discontinuously applying the photoresist in the length direction of the metal magnetic film and the insulating film exposed to the upper surface of the junction of the pair of core block bodies by the length of the track width region to be formed; A fifth step of removing the magnetic metal film and the insulating film corresponding to a region other than the photoresist to a gap depth; A sixth step of removing the photoresist and fusing the molding glass to the upper portion of the coil winding groove formed through the center of the pair of core block bodies and the groove of the bottom surface formed in the third step; And a seventh step of cutting the pair of core block bodies so as to pass through a central portion of a circular conduit formed by a plurality of grooves abutting on the inner wall of the joint portion. 7. . 7. The method of claim 6, wherein in the second step, the magnetic metal film is formed by sputter deposition of any one selected from sendust, permalloy, and Fe-N-based microcrystalline alloys. . 8. The method of manufacturing a magnetic head for magnetic recording and reproduction according to claim 7, wherein the permalloy alloy is any one selected from FeRuGaSi and FeIrGaSi. 7. The method of manufacturing a magnetic head for magnetic recording reproduction according to claim 6, wherein the insulating film is one selected from SiO ₂ and Al ₂ O ₃ . The magnetic head for magnetic recording reproduction according to claim 6, wherein the magnetic metal film and the insulating film corresponding to the regions other than the photoresist applied in the fifth step are removed to a gap depth by a reactive ion etching process. Manufacturing method.