JPH0458641B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a new magnetic recording method that allows high-density and highly accurate recording and reproduction, and particularly to a new perpendicular magnetic recording method that can easily be multitracked.

Conventional magnetic recording devices include horizontal recording devices that record in the longitudinal direction of a recording medium and perpendicular recording devices that record in the thickness direction of a magnetic layer of a recording medium.

FIG. 1a is a schematic diagram of an example of a conventional horizontal recording device, and FIG. 1b is a schematic diagram for explaining a recording medium.

The horizontal recording device has a recording medium 1 and a ring head 2.
It consists of

The recording medium 1 is composed of a substrate 3 and a magnetic layer 4 provided on the surface in contact with the head 2.

As shown in FIG. 1b, the magnetic layer 4 is formed by forming an N pole (+) and an S pole (-) on a magnet having a length l and a thickness d. They are lined up against each other.

The length A-A' portion shown in Figure 1b is shown in Figure 1a.
The magnetic layer 4 is shown as a magnetic layer 4 of FIG.

The ring head 2 consists of a ring-shaped magnetic core 5 and a coil 8 having signal input terminals 6, 7.

Recording in this device is performed by the ring head 2 according to input signals input from the outside to the input terminals 6 and 7.
This is done by changing the magnetizing force in the running direction V of the recording medium 1 by the flux 10 generated from the air 9 in the magnetic core.

A conventional horizontal recording device has a distance l shown in Fig. 1b.
This has the major drawback that the shorter the length of the magnetic field, or in other words, the higher the recording density, the greater the effect of demagnetization.

FIG. 2a is a schematic diagram of an example of a conventional perpendicular recording device, and FIG. 2b is a schematic diagram for explaining a recording medium.

For example, a perpendicular recording device uses a recording medium 11.
, a main magnetic pole 12 , and an auxiliary magnetic pole 13 .

The recording medium 11 consists of a substrate 14 and a magnetic layer 15.

Unlike the case of horizontal recording, the magnetic layer 15 has a shape in which magnets are erected perpendicularly to the medium surface and arranged so that north poles and south poles alternately appear on the surface.

The length B-B' portion shown in Figure 2b is shown in Figure 2a.
The magnetic layer 15 is shown as a magnetic layer 15 of FIG.

In this device, the ring head hole (9 in FIG. 1a) of the horizontal recording device is replaced by a main pole 12 made of a strip of soft magnetic thin film (thickness 1 μm or less).

The main pole 12 is held by a non-magnetic material.

The auxiliary magnetic pole 13 is provided facing the main magnetic pole 12 and is formed by having a coil 18 having input terminals 16 and 17 on the outside.

During recording, the magnetic layer 15 of the recording medium 11 contacts the main magnetic pole 12 and moves in the direction of arrow V in the figure. At this time, the perpendicular magnetic field of the main magnetic pole 12 generated by excitation from the auxiliary magnetic pole 13 19, the signal is transmitted to the magnetic layer 1
5, recorded in the thickness direction.

Therefore, recording in this device has the advantage that an attractive force acts on all adjacent magnets (signals) and reduces the demagnetization effect to zero, but when the main magnetic pole 11 and the auxiliary magnetic pole 13 are separated from each other, Therefore, it is necessary to flow a large amount of current depending on the distance, and furthermore, in practical use, the magnetic layer 15 has major drawbacks such as requiring an internal Fe-Ni film or permalloy layer of about 0.5 μm. are doing.

FIG. 3 is a schematic diagram of another example of a conventional perpendicular recording device.

This device is composed of a recording medium 21, a main magnetic pole 22, and an auxiliary magnetic pole 23, but unlike the example shown in FIG. However, both are provided in one surface direction of the recording medium 21.

The recording medium 21 is formed by having a magnetic layer 25 on one side of a substrate 24 and an Fe--Ni film 26 thereon.

The magnetic layer 25, like the magnetic layer 15 shown in FIG. 2b, is formed in a shape in which N poles and S poles are arranged alternately on the surface, that is, it has perpendicular anisotropy.

The feature of the apparatus shown in this example is that it has almost the same configuration as the ring head 2 for horizontal recording shown in FIG.
In Figure a, 9) is made wider (15 μm), and the film thickness of the main magnetic pole 22 is made thinner than that of the auxiliary magnetic pole 23. This structure is
This has the advantage that the magnetic field component perpendicular to the surface of the recording medium 21 at the tip of the main pole 22 having the coil 28 becomes steep, and the Fe--Ni film 26 is actively utilized as a part of the head. In other words, the recording medium 21
The Fe--Ni film 26 becomes a magnetic path 29 between the main magnetic pole 22 and the auxiliary magnetic pole 23, and the magnetic flux gathers under the main magnetic pole 22. Since the magnetic flux is spread under the auxiliary magnetic pole 23, no recording or reproduction is performed here, but it has the disadvantage that it is not possible to move the track in the opposite direction to record.

Figure 5 shows an example in which a main magnetic pole is installed so as to be magnetized in a direction perpendicular to the track running direction, and an auxiliary magnetic pole is installed in a direction perpendicular to the traveling direction of the recording medium, adjacent to or sandwiching the main magnetic pole. show. Therefore, the magnetization pattern is arranged in a shape that crosses the track running direction as shown in FIG. 4, and is also magnetized in the perpendicular direction by disposing a high magnetic permeability layer under the magnetization film layer of the recording medium.

When the length of the magnet is shortened to increase the recording density in the conventional horizontal recording method (Figure 1bA
-A'), the demagnetizing field becomes large, and in order to solve this problem, it is necessary to narrow the track width, reduce the film thickness, and increase the coercive force. There is also a limit in terms of the coercive force of the material, and therefore there is a limit to increasing the recording density.

The magnetization structure shown in FIG. 5 has the advantage that the above disadvantages can be completely ignored because the length of the magnet is in the width direction and perpendicular direction of the running track. Furthermore, since the magnetic field forms a closed magnetic path in the direction perpendicular to the track running direction for recording, when a multi-track is formed, there is extremely little mutual interference between the tracks. For example, if one track is configured with a width of about 100 μm,
If the multi-track running surface is 1 cm, more than 100 channels can be constructed, and the magnetization division in the running direction is
^Since it is possible to record with a width of 0.5 μm or less,
It has the feature of being able to record more than 2,000,000 bits.

Furthermore, since there is a limit to the recording density in the horizontal recording method, the perpendicular magnetization recording method described above has been proposed. The vertical head of the perpendicular magnetization recording system is an auxiliary magnetic pole excitation type that is configured to sandwich the recording medium.
There are main magnetic pole excitation types with auxiliary magnetic poles, etc., and in particular, the auxiliary magnetic pole excitation type (Figure 2 a) uses a high magnetic permeability material for the main magnetic pole to increase playback sensitivity and achieve high recording density. Because it has a structure (open magnetic path) that sandwiches the recording medium, it is effective for magnetic tapes and floppy disks, but cannot be used for hard disk devices. Furthermore, it becomes difficult to use magnetic tapes or floppy disks when the substrate layer is made thicker to increase their strength. Furthermore, the multitrack recording system has the disadvantage that it is extremely difficult to use because it forms an open magnetic path, which causes mutual interference.

In the perpendicular magnetization recording method, a method has been proposed in which the high magnetic permeability layer of the recording medium is used as part of the magnetic head from the top surface and perpendicular magnetization is performed without placing an auxiliary magnetic pole on the back surface, as shown in FIG. In this case, since magnetic flux is formed in the direction of track movement, the track movement direction is limited to one direction and recording cannot be performed in the opposite direction.

FIG. 5 described above shows a prior art recording method in which the recording medium is magnetized in a direction perpendicular to the traveling direction. A magnetic head that generates a magnetic field in a direction perpendicular to the track running direction is installed, and the recording medium is coated with a magnetized film 40 such as a Co-Cr film as shown in FIG.
It is lined with a high magnetic permeability layer 41 such as a Ni-Fe (permalloy) layer. If this high magnetic permeability layer is made of super permalloy, which is made by adding Mo, Mn, Cr, etc. in addition to Ni-Fe, the magnetic permeability will be further improved.
The magnetization becomes even better. Further, in the case of a medium that does not have a high magnetic permeability layer, perpendicular magnetization can be achieved by placing an auxiliary magnetic pole made of high magnetic permeability such as permalloy that performs the same effect on the back surface of the medium. The magnetic head is composed of two main magnetic poles, and the magnetic flux passes from one main magnetic pole to the magnetic film 40 of the recording medium, the high permeability layer 41, passes through the magnetic film 40 again, and goes to the other main magnetic pole of the same magnetic head. Connect to form a closed circuit. Naturally, the reverse route can also be used.

Therefore, as shown in FIG. 4, the magnetized film 40 on the recording medium has a pair of + and - poles in the vertical direction, and a pair of + and - poles in the direction perpendicular to the horizontal component of the track running direction. recorded. The gap between the main magnetic poles A and B can be configured to be very narrow, and since the two main magnetic poles form a closed magnetic path with concentrated magnetic flux, the magnetic flux density per unit cross-sectional area is large, and therefore during playback. The detection voltage is also large. However, the magnetization pattern is arranged on a plane including the track running direction, and there is a limit to the recording density.

The purpose of the present invention is to propose a completely different new perpendicular magnetization recording method, and to achieve increased recording density and superiority in multi-track performance. Another object of the present invention is to provide a new recording direction that allows high-density recording regardless of the direction of travel. Still another object of the present invention is to provide a recording system with a very high reproduction output voltage.

FIG. 7 shows the present invention, which is composed of a main magnetic pole and an auxiliary magnetic pole having a larger cross-sectional area than the main magnetic pole. In this case, only one pole is recorded in the horizontal component of the track running direction, resulting in only vertical magnetization recording. However, unlike the conventional perpendicular magnetization method, recording is possible in either direction of track travel.

The cross section of the main pole may be long in the track running direction, or conversely short in the track running direction.

When a multi-head is constructed of main magnetic poles having a short shape with respect to the track running direction, they can be arranged so as to overlap to the extent that each does not affect the magnetic flux of the adjacent track, as shown in FIG. This allows the distance between each track to be shortened, making it possible to achieve even higher density. Furthermore, since each main magnetic pole pair is constituted by a closed magnetic path, the influence of inter-track comrades is extremely small. 8th
The figure is a plan view of an example in which the main magnetic poles are installed on both sides of the auxiliary magnetic poles. In this case, unlike the structure shown in FIG. 4, the same polarity is recorded in the horizontal component direction on the magnetized medium, as shown in FIG. 9. Therefore, a very large value can be obtained for the reproduction output voltage.

FIG. 10 is a plan view of an example in which the structure of FIG. 8 is configured as a multi-track. Even in this case, since each main magnetic pole and auxiliary magnetic pole are constituted by a closed magnetic path, there is no effect even if the main magnetic poles of adjacent tracks are close to each other.

FIG. 11 shows an embodiment of a recording and reproducing circuit for multi-track. As described above, the present invention is excellent in separating each track, and since a very large number of tracks can be constructed, track movement in the running direction of the recording medium and sequential recording in the perpendicular direction can be performed electrically. The signal can be recorded at any position, and matrix recording can be performed in the running direction and in the right angle direction. Recording in the opposite direction,
Needless to say, it can be played back.

The magnetic head used in the magnetic recording/reproducing apparatus of the present invention will be explained. FIG. 12 shows the structure of the tip of a multihead in which one main magnetic pole and a large number of adjacent auxiliary magnetic poles are arranged in a direction perpendicular to the traveling direction of a magnetic tape or magnetic disk. Recording and reproduction are performed by one main magnetic pole 111 and one auxiliary magnetic pole 112 provided on a non-magnetic material substrate, such as a fused quartz substrate or a glass substrate 121. The number of main magnetic pole pairs is determined based on the dimensions of the magnetic tape or magnetic disk and the desired number of recording channels. The arrows in the figure indicate the direction of movement of the magnetic tape or magnetic disk. The gap g between adjacent magnetic poles, the thickness d in the advancing direction of the main magnetic pole, the width W, and the spacing l between each head are designed to desired values. 122 is CVD (Chemical
SiO ₂ deposited by Vapor Deposition method etc.
It is. Alternatively, resins that harden at relatively low temperatures,
For example, it may be made of polyimide resin.

FIG. 13 shows a plan view of the multi-head shown in FIG. 12, which uses a main magnetic pole and adjacent auxiliary magnetic poles, when viewed from above. A plan view of one head is shown in FIG. Main pole 111,
112 are connected in a so-called ring shape by a magnetic material 113, as shown in the figure. 1
11, 112, and 113 are usually made of the same material. In order to be able to reduce the magnetomotive force during recording and increase the reproducing voltage, this material is particularly required to have a large saturation magnetic flux density Bs and a high initial magnetic permeability μi. Usually, it is a Cu-Mo permalloy film or a Co-Zr amorphous film. Cu−
Bs of Mo permalloy film is 6000 Gauss, μi is 2600,
The coercive force Hc is 0.10e and the maximum permeability μmax is 13000.
On the other hand, in the Co-Zr amorphous film, Bs=
13000 Gauss, Hc=0.120e, μi=4000, μmax=
It is 7500. Fe-Ni permalloy with Mo, Cr,
The initial magnetic permeability of super permalloy with a small amount of Mu added becomes even higher. Naturally, super permalloy film can also be used as the main pole material. Main magnetic pole 11
1 and the auxiliary magnetic pole 112, a thin film of a high magnetic permeability material, such as permalloy or super permalloy, or Co-Zr amorphous, is provided on the base material, and on top of that, Co-
A magnetic tape or magnetic disk provided with a thin film of a material having perpendicular magnetic anisotropy, such as Cr, Co-Mo, Co-W, Co-V, etc., is arranged. 13th
114 indicated by a dotted line in the figure is the main magnetic pole thin film 11
1, 112, and 113, metal wiring such as Al is provided through an insulating layer such as SiO ₂ .

115 indicated by a solid line is the main magnetic pole thin film 11
1, 112, and 113, an insulating layer thin film such as SiO ₂ is provided, and a metal wiring such as Al is provided on the insulating layer thin film. The upper and lower two layers of metal wiring are in contact through contact holes at the overlapping parts 116...117... outside of the main pole material thin film. In Figure 13,
It has a structure in which a 21-turn coil is wound around a ring-shaped main pole. The dimensions are outlined below. In order to increase the recording density in the traveling direction of a magnetic tape or magnetic disk, it is desirable that the thickness d of the main magnetic pole thin film is as thin as possible. For example, it is set to about 0.1 μm to several μm. In order to increase the reproduction voltage from several 10 μV to several 100 μV, the width W of the main magnetic pole needs to be approximately several 10 μm to several 100 μm. Naturally, in order to increase the recording density,
It is desirable that this width be small. In a device such as a magnetic disk that does not cause lateral vibration, it is desirable to reduce the width W of the main pole as long as the amplifier capacity of the detection system is increased, since this increases the recording density. Even in magnetic tapes, if a mechanical system is used to reduce lateral vibration, the number of tracks increases as the width of the main pole decreases, and the recording density increases. As the magnetomotive force that substantially saturates the vertical magnetic charge, a 0.15 to 0.2 A turn is sufficient since the device of the present invention has an almost completely closed magnetic circuit system. If a 21-turn coil is wound around the main pole as shown in Figure 13,
A maximum current of about 10 mA is sufficient for the current flowing through the coil. When Al is used for the metal wiring, the maximum allowable current density in the Al wiring is about 1×10 ⁵ A/cm ² in consideration of migration. Therefore, the 13th
In the figure, the width of the Al layer wound around the main pole is 6 μm and the thickness is 2 μm. When 10mA flows
The current density in Al is 8×10 ⁴ A/cm ² . The width of the Al wiring in the current introducing portion to the head portion is approximately 15 μm, and the thickness is approximately 2 μm. The width W of the main pole in Figure 13 is approximately 50μm, and the gap is approximately 1μm.
It is m. The width of the ring-shaped magnetic thin film is approximately 15 μm. Of course, the gap can also be made narrower than 1 μm. Of course, these values can be set to desired values.

In this head where the main magnetic pole is 1 μm thick, the super permalloy high permeability layer of the recording medium is 1 μm thick,
By using a recording medium configured with a Co--Cn perpendicular magnetic layer having a thickness of 0.5 μm, a reproduction voltage of about 100 μV has been obtained.

The metal wirings 114 and 115 are formed widely up to the main magnetic pole introduction part of the head. This is to reduce the resistance value. The metal wirings 114 and 115 are connected at their upper parts to a recording signal generator and a reproduction voltage amplifier, respectively. Since a relatively large magnetomotive force is required during recording, the wiring electrode of the excitation coil becomes wide, as can be seen from FIG. This is mainly determined by metal migration. Furthermore, when using a small head, the allowable current that causes migration may be large.
Al-Cu metal may be used. Although it is a little more expensive, if Au is used, the maximum allowable current at which migration occurs will be one order of magnitude larger than that of Al. In other words, it is optimal for miniaturization heads. The structure of the head shown in FIGS. 12 and 13 is merely an example. The structure of the ring-shaped main pole only needs to be a closed magnetic path, so it can be of any shape. Further, the winding is not limited to that shown in FIG. 13. Any structure may be used as long as it wraps around the ring-shaped main pole. The lead wires 114 and 115 are arranged outside the ring-shaped head. When the heads are packed even more densely, if four-layer metal wiring is used, the lead-out wirings 114 and 115 can be arranged above and below the ring-shaped main pole.

In FIG. 13, the lead-out wires for adjacent heads may be placed immediately adjacent to the wires 114 and 115 in FIG. It is sufficient as long as electrical insulation is ensured.

The structure of other heads will be explained next. 14th
Figures 1 to 16 show the structure of the tip of the head. In both cases, main magnetic poles 101 and 1 are provided in a non-magnetic material 103.
05 or auxiliary magnetic poles 102, 104 are embedded. The main magnetic pole and auxiliary magnetic pole materials are made of high magnetic permeability material, as described above. In both figures, arrows indicate the running direction of the magnetic tape or magnetic disk. In FIG. 14, main poles of the same size are facing each other. Of course, the main magnetic poles 101 are connected in a ring shape in the direction perpendicular to the plane of the paper, and the coil is wound with the required number of turns. Illustrated dimensions
l ₁ , l ₂ , d ₁ , g ₁ , and W ₁ may be designed according to each purpose. If a large number of heads shown in FIG. 14 are stacked vertically, a multi-head like that shown in FIG. 12 will be obtained.

In the structure shown in Fig. 15, one of the main magnetic poles has a large area, and this is temporarily expanded to the auxiliary magnetic pole 10.
Call it 4. The situation in which the main magnetic pole 101 and the auxiliary magnetic pole are connected on a ring in the direction perpendicular to the plane of the paper and the coil is wound is the same. In this example, recording is mainly performed with the main magnetic pole 101. In the example in Figure 14, 10
This means that both No. 1 and No. 1102 performed writing. In FIG. 15, an auxiliary magnetic pole may also be provided above the main magnetic pole 101. So to speak, it is E-shaped when viewed from left to right. Needless to say, each coil is wound individually.

Conversely, the main magnetic pole 101 is placed above and below the auxiliary magnetic pole 104,
FIG. 16 shows the one in which 105 is provided. 101 and 104, and 105 and 104 are connected in a ring shape, respectively. In this case, each party's signals may leak to the other party.

In any case, the basic operation is shown in Figure 12, 1.
It is similar to the one in Figure 3.

Next, an example of manufacturing the multihead shown in FIGS. 12 and 13 will be briefly described.

A case where a fused silica substrate (200 to 500 μm thick) is used will be described. After thoroughly cleaning to eliminate the contaminant layer, metals such as Al, Al-Cu, and Au are deposited, sputtered, and CVD (plasma CVD, photoexcited CVD)
), or deposited on a quartz plate by electroless plating, plating from a solution by light irradiation, etc.
In the case of laser plating from a solution, patterned plating can be performed. When metal is deposited on the entire surface, a normal photolithographic process is used to leave the first layer pattern for the lead-out electrode and coil winding shown by dotted lines in FIG. 13, and remove the rest by etching. Photo-excited CVD is performed by leaving the resist on the metal wiring as it is.
The SiO ₂ film is deposited to the same thickness as the metal film. For example, when using SiH ₄ and N ₂ O as the source gas, mercury evaporation is added to the source gas at the same time, and 2537.5 Å from a low-pressure mercury lamp is externally irradiated.
Hg gas is excited to an excited state, and the excited Hg molecules react with _N2O to generate oxygen radicals, which react with _SiH4 ,
SiO ₂ is deposited. In this photoexcited CVD, 50℃−
Relatively good SiO ₂ can be obtained at a substrate temperature of about 150°C. Afterwards, when the resist is etched, the SiO ₂ film on the resist is also removed due to lift-off, so the metal film and SiO ₂ CVD film become almost flat. On top of this state, a SiO ₂ film is further CVDed.
deposited in The thickness may be arbitrarily selected from about 0.2 μm to about 2 μm. The thinner the thickness, the smaller the recording current and the larger the reproducing voltage. This CVD may be the photo-excited CVD described above, or may be a normal CVD based on SiH ₄ and O ₂ . A SiO ₂ film of sufficiently good quality can be obtained at a substrate temperature of about 300 to 350°C. 0.2μm
, its withstand voltage field exceeds 8×10 ⁶ V/cm. Furthermore, on top of this SiO ₂ film, a main pole material with the required high magnetic permeability, such as permalloy film,
Super permalloy film, Cu-Co permalloy film,
A Co-Zn amorphous film is usually deposited by high-frequency sputtering. In some cases, it can also be attached by vapor deposition. A photoresist is applied, and unnecessary portions of the high magnetic permeability film are etched using a normal photolithography process. Film thickness is 0.1μm ~ 3μm
The desired thickness may be approximately 1.5 m. The resist on the patterned high magnetic permeability film is left as is, and the SiO ₂ film is deposited again in the same amount as the high magnetic permeability film by photo-excited CVD. When the resist is removed, the SiO ₂ on the resist is also removed by lift-off, and the surfaces of the high magnetic permeability layer and the SiO ₂ layer are flat with almost no unevenness. Further, a SiO ₂ film is deposited thereon to a required thickness by CVD or photo-excited CVD. 0.1～
The necessary value can be selected from about 1 μm. In the photolithography process, a contact hole is etched in the SiO ₂ film so that contact can be made with the underlying Al, and then a metal such as Al or Al-Cu is deposited using the method described above. If unnecessary portions of Al are etched in a photolithography process, a pattern as shown in FIG. 13 can be obtained. Furthermore, a CVD film of SiO ₂ may be deposited thereon. It is also effective to use other resin films.

Here, the case where the insulating film is SiO ₂ has been described. Since the substrate is SiO ₂ , the thermal expansion coefficients match, which is very convenient. It is also possible to use others.

As explained here, the multi-head manufacturing method can be performed through a nearly complete self-alignment process, and is a process that always ensures a flat surface, making it extremely easy to miniaturize. By introducing miniaturization technology at the VLSI level, it is possible to reduce the size of the head to the level of several micrometers. In particular, as already explained, if the head is constructed in multiple layers,
The density of the multihead can be made sufficiently high, and the characteristics during recording and reproduction can be kept sufficiently good.
In short, an integrated multihead with sufficiently good characteristics can be easily produced.

According to the present invention, perpendicular magnetization recording that is reproducible in both the forward and reverse directions can be realized. Further, according to the present invention, multi-tracking is easy, and
Furthermore, since extremely large reproduction outputs can be obtained, ultra-high density recording can be performed. The present invention enables recording and reproduction in a horizontal plane perpendicular to the track running direction on a recording medium having at least one thin magnetic film layer on the base material, and in particular uses an integrated multi-head. In some cases, extremely high-density recording can be performed, and its industrial value is high. According to the present invention, the horizontal magnetization component within the same track is effectively zeroed, and the mutual demagnetization effect between adjacent tracks is zeroed, thereby facilitating multi-track construction. According to the present invention, the same polarity is recorded in the horizontal component direction within the same track, the reproduction output voltage becomes very large, the spacing loss is small, and high density is easily achieved. According to the present invention, since the influence of the magnetization component of the magnetic recording medium in the portion facing the auxiliary magnetic pole can be reduced, distortion during reproduction can also be reduced.

[Brief explanation of drawings]

Figure 1a is a conventional example of a horizontal recording device, b is a magnetization pattern using a horizontal recording system, Figure 2a is a conventional example of a perpendicular recording device, b is a magnetization pattern using a perpendicular recording system, and Figure 3 is a vertical recording pattern using a ring head structure. 5 shows a conventional example of a magnetic recording device that generates a magnetic field perpendicular to the track running direction, FIG. 4 shows its magnetization pattern, and FIG. 6 shows a multihead structure using the present invention. One embodiment, FIG. 7 shows an embodiment of the present invention in which the auxiliary magnetic pole is arranged perpendicular to the track running direction with respect to the main pole, and FIG. Figure 9 shows an example of a magnetization pattern using two main magnetic poles and one auxiliary magnetic pole, Figure 10 shows an example of a multi-track structure using an auxiliary magnetic pole, and Figure 11 shows an example of a recording and reproducing circuit with a multi-track structure. Fig. 12 shows the tip structure of a two-main magnetic pole multihead, Fig. 13 shows a plan view of one head constituting the two-main magnetic pole multihead, and the first
Figure 4 shows the tip structure of the two main magnetic pole type head, Figure 15 shows the tip structure of the main pole auxiliary magnetic pole type head, and Figure 16 shows the tip structure of the main pole auxiliary magnetic pole type head.
The figure shows the tip structure of a head with two main magnetic poles and an auxiliary magnetic pole.

Claims (1)

[Claims] 1. On the horizontal plane of the magnetic recording medium, one auxiliary magnetic pole and two main magnetic poles having a smaller cross-sectional area than the auxiliary magnetic pole are arranged on both sides of the auxiliary magnetic pole in a direction perpendicular to the moving direction of the magnetic recording medium. configuring a multi-magnetic head structure by arranging a plurality of magnetic heads in a direction perpendicular to the moving direction of the magnetic recording medium;
A high-density magnetic recording method characterized in that multi-track magnetic recording is performed by using the multi-head structure.