JPH11328662A - Magnetic recording medium and magnetic recording device - Google Patents

Abstract

(57) [Summary] [Problem] It is possible to remove recording bleeding, to effectively employ a perpendicular magnetic recording method even though it has a single-layer film structure, and to realize higher density recording. A magnetic recording medium and a magnetic recording device are provided. SOLUTION: An information signal is recorded on a magnetic disk 3 by a recording head 8a mounted on a head slider which at least partially floats during recording. The magnetic disk 3 includes a substrate 13 on which a magnetic layer 14 having perpendicular magnetic anisotropy is formed, a predetermined uneven pattern is formed on the surface of the disk medium, and the convex portions 3 of the predetermined uneven pattern are formed.
Information width W ₁ direction perpendicular to the traveling direction of the recording head 8a in a can, the recording track width W ₂ or less of the recording head 8a, the convex portion 3a by means of a perpendicular magnetic recording system by recording head 8a The signal is recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic recording medium and a magnetic recording apparatus in which information signals such as data and programs are recorded by a recording head mounted on a head slider that at least partially floats during recording. Things. In particular, it relates to a magnetic recording medium on which information signals are recorded by a perpendicular magnetic recording method.

[0002]

2. Description of the Related Art In recent years, the density of magnetic disks has been increasing year by year, and has been increasing at a rate of 60% per year. This increase in the density of the magnetic disk has been realized by employing a magnetoresistive magnetic head (MR head) or the like, improving the magnetic material, and the like. In addition, as a method for increasing the density of a magnetic disk, great progress has been made by reducing the distance between the magnetic head and the magnetic disk as much as possible.

More specifically, the recording density of a magnetic disk is reduced by using a magneto-resistance effect type magnetic head (MR head) or a giant magneto-resistance effect type magnetic head (GMR head) called a next-generation reproducing head. 10Gbit / in
It is believed that the density can be increased to ^two levels.

By the way, in the conventional longitudinal magnetic recording system,
For example, as shown in FIG. 27, a magnetic disk 100 has a magnetic layer 102 formed on a substrate 101, and is easily magnetized in the longitudinal direction and has strong residual magnetization. A magnetic field is applied to the longitudinal direction of the magnetic disk 100 by a magnetic head such as a ring-shaped head 103.

However, as described above, when the recording density of a magnetic disk is increased to a level of 10 Gbit / in ² , it is difficult to sufficiently apply the above-described longitudinal magnetic recording method. As a problem on the side, a phenomenon of so-called thermal fluctuation emerges.

[0006] The phenomenon of thermal fluctuation refers to an unstable state of magnetic energy that occurs when the magnetic particles become smaller and the thermal vibration energy of the spin of the magnetic particle material increases as the magnetic energy exceeds the stable state of magnetic energy. When this unstable state occurs, in the magnetic disk, the magnetization of the magnetic signal once recorded is inverted from the N pole to the S pole and from the S pole to the N pole at room temperature due to the thermal energy of the spin of the magnetic particle material. And cannot be used as a recording medium.

One of the means for solving such a thermal fluctuation phenomenon is a perpendicular magnetic recording system. This perpendicular magnetic recording system was originally actively researched in the late 1970s and 1980s as a device capable of achieving higher density recording than the conventional longitudinal magnetic recording system as shown in FIG. This method is also excellent in terms of eliminating the thermal fluctuation phenomenon.

[0008] However, this perpendicular magnetic recording system is not shown in FIG.
In order to use a device different from the conventional longitudinal magnetic recording system as shown in FIG. 1, the magnetic recording device has not been actively developed. FIG. 28 shows how a magnetic field from a single pole head is applied to a recording medium by the perpendicular magnetic recording method.

More specifically, when a magnetic field from a magnetic head is applied to a recording medium in a perpendicular magnetic recording system, a recording medium such as a magnetic disk 110 is provided with a high magnetic permeability layer 112 on a substrate 111 as shown in FIG. , A perpendicular magnetic recording layer 113 is sequentially formed. Therefore, such a conventional recording medium is called a two-layer film medium. Here, the reason why the high magnetic permeability layer 112 is provided is that the magnetic field in the vertical direction is more concentratedly applied to the surface of the perpendicular magnetic recording layer 113.

As a recording head for recording an information signal on the recording medium by the perpendicular magnetic recording method, a single pole head 114 capable of producing more perpendicular magnetization components than the conventional ring type head 103 is employed. You.

However, the existence of the high magnetic permeability layer causes various problems. That is, the rigidity of the recording medium itself increases due to the presence of the high magnetic permeability layer. For example, when the application to a tape medium is considered, the rigidity of the tape itself increases. In some cases, the tape did not wind around the roll or the like, causing a problem in running the tape.

Further, an alternating magnetic field flows through the high magnetic permeability layer regardless of recording or reproduction.
The domain wall always moves, and the motion of the domain wall causes noise at the time of signal reproduction, which causes a problem that a high quality signal cannot be reproduced.

In order to solve these problems, a so-called single-layer film medium in which a perpendicular magnetic recording layer is directly provided on a substrate without providing a high magnetic permeability layer below the perpendicular magnetic recording layer has been developed. More development groups are hiring. This so-called single-layer film medium does not have a high magnetic permeability layer for applying and applying a perpendicular magnetic field in a concentrated manner. Therefore, use a single-pole head used when performing a perpendicular magnetic recording method with a two-layer film medium. Can not. Therefore, the strength of the perpendicular magnetic field applied to the perpendicular magnetic recording layer of the single-layered medium is lower than the strength of the perpendicular magnetic field applied to the perpendicular magnetic recording layer of the two-layered medium.

Instead of the single-layer film medium, a magnetic head such as a ring-type head used in a conventional magnetic recording system can be used for the single-layer film medium. Therefore, it is advantageous in that the cost of the magnetic disk device itself can be reduced. Furthermore, unlike a two-layer film medium, a single-layer film medium does not have a high magnetic permeability layer, so that it has the same rigidity as other conventional recording media other than the two-layer film medium. it can.

Further, the use of this single-layer film medium in the perpendicular magnetic recording system is also a perpendicular magnetic recording system, similar to the use of the two-layer film medium in the perpendicular magnetic recording system. This is advantageous with respect to the fluctuation phenomenon. That is, the problem such as the thermal fluctuation phenomenon which the longitudinal magnetic recording system faces can be solved by the perpendicular magnetic recording system using a single-layer film medium.

[0016]

However, in a magnetic recording system in which a so-called single-layer film medium is combined with a conventionally known magnetic head such as a ring type head,
There are issues that need to be solved as described below.

That is, there is a problem of how to achieve a low flying height of a flying slider on which a magnetic head is mounted, and a problem of how to eliminate blurring of recording.

Specifically, the low flying height of the flying slider is required for the following reasons. As described above, since a single pole head cannot be used in the single-layer film medium, a conventional ring-type head is generally employed.

However, the vertical magnetic field produced by the ring head is weaker than the longitudinal magnetic field. Therefore, no matter how perpendicular magnetic anisotropy exists in the recording medium itself, it is difficult to completely leave magnetization in the perpendicular direction. Further, the magnitude of the magnetic field generated by the ring-shaped head differs depending on the distance from the ring-shaped head to the recording medium. Therefore, the magnitude of the vertical magnetic field generated by the ring head also varies depending on the distance from the ring head to the recording medium. Therefore, the relationship between the distance from the ring-shaped head and the strength of the magnetic field generated by the ring-shaped head was obtained from Westmize's magnetic field calculation formula.

FIG. 29 shows the calculation result. In FIG. 29, the abscissa indicates a value y / g obtained by standardizing the spacing amount y, which is the distance from the ring head, by the gap length g of the ring head, and the ordinate indicates the magnetic field generated from the ring head. Of the magnetic field H in the gap of the ring-shaped head
_The value H / H ₀ normalized by ₀ was taken.

The circles indicate the x component of the magnetic field generated from the ring type head, that is, the magnetization component in the longitudinal direction. The straight line is a component in a direction corresponding to the y component of the magnetic field generated from the ring-shaped head, that is, the perpendicular magnetization component. The + mark is
It shows the magnitude of the magnetic field obtained by combining the x component of the magnetic field indicated by a mark and the y component of the magnetic field indicated by a straight line.

As can be seen from FIG. 29, when the distance y / g from the ring-type head standardized by the gap length of the ring-type head becomes 0.4 or less, the magnitude of the magnetic field generated from the ring-type head becomes smaller. It can be seen that the y component, that is, the perpendicular magnetization component is larger than the longitudinal magnetization component than the x component. It can also be seen that the smaller the distance from the ring head, the greater the perpendicular magnetization component.

From this, when a perpendicular magnetization type single layer medium is used, the smaller the distance from the ring head to the single layer medium, the stronger the perpendicular magnetic field from the ring head is. You can do it. Although not shown in the figure, the strongest vertical magnetic field can be received when the spacing amount, which is the distance from the ring-shaped head to the recording medium, is 0 in the calculation. The longitudinal magnetization component at that time is almost zero.

Therefore, as the distance from the ring-type head to the recording medium approaches 0, the direction of the magnetic field from the ring-type head becomes almost perpendicular to the surface of the recording medium, which is ideal for a perpendicular magnetic recording system. It can be said that it approaches.

From the above results, when a ring-type head is used for a single-layered medium in the perpendicular magnetic recording system, the distance between the single-layered medium and the magnetic head is limited in order to apply a sufficient perpendicular magnetic field. And it must be close to zero.

That is, in a magnetic recording apparatus, in which recording is performed on a magnetic recording medium having a single-layer film structure by using a conventional magnetic head such as a ring-type head, the perpendicular magnetic recording method is used. It can be said that the problem is to reduce the flying height from the medium surface.

Next, the problem of recording bleeding will be described. Originally, the information signal should be recorded only in the area on the recording medium facing the recording track width of the recording head. However, actually, an information signal may be recorded on a recording medium by a magnetic field generated from a portion other than the recording track width of the recording head, that is, a side surface of the recording head that is not opposed to the recording medium. The phenomenon that an information signal is recorded on a recording medium by such a magnetic field is called so-called recording bleeding.

When such recording bleed occurs, the information signal of the recording bleed portion does not match the phase of the information signal recorded on the normal recording track, resulting in noise. In addition, due to the presence of the recording blur, it is difficult to reduce the track density and the linear density in order to obtain normal recording / reproducing characteristics, and it is not possible to increase the recording density.

For example, FIG. 30 schematically shows a magnetization pattern recorded on a magnetic disk 120 having a normal flat surface by a recording head. In FIG. 30, different magnetization patterns are shown as magnetization patterns a and b.

As shown in FIG. 30, at the band-shaped central portion 121 on the magnetic disk 120 substantially parallel to the track direction A,
Although the phases of the information signals are aligned, the portion where the phases are aligned is an area facing the recording track width of the recording head.

In the regions 122 located on both sides of the band-shaped central portion 121, a signal having a phase delayed from the information signal recorded on the regular recording track is recorded.
This area 122 is a place where an information signal is recorded on the magnetic disk 120 by a magnetic field generated from a place other than the recording track of the recording head facing the magnetic disk 120, and is called so-called recording blur.

In the perpendicular magnetic recording system using a single pole head, the recording bleeding is caused by the fact that the side surface of the single pole head is extremely small, and the magnetic field generated from the single pole head is located below the perpendicular magnetic recording layer. It hardly occurs because it is drawn in the magnetic permeability layer.

However, when a ring head is used, the phenomenon of recording bleeding increases as the distance between the magnetic head and the recording medium decreases or as the gap length of the recording head increases. This is a phenomenon that occurs similarly regardless of the longitudinal magnetic recording method or the perpendicular magnetic recording method.

Here, FIGS. 31 and 32 show magnetization patterns in the case of the perpendicular magnetic recording system using a single pole head and in the case of the longitudinal recording system using a ring type head, respectively. As shown in FIGS. 31 and 32, it can be seen that the recording bleeding is smaller in the perpendicular magnetic recording method using the single pole head than in the case of using the ring head.

As described above, in the perpendicular magnetic recording system using a single-layer film medium, it is necessary to make the distance between the head and the recording medium as close to zero as possible and eliminate the recording blur. It has been found that it is necessary to sufficiently exhibit the characteristics of the perpendicular magnetic recording system using the method for achieving higher density recording.

Accordingly, various studies have been made on a method for making the distance between the magnetic head and the recording medium as close to zero as possible and a method for eliminating the recording bleeding phenomenon as described below.

In general, various contact recording methods have been proposed for a magnetic recording apparatus as a method for making the distance between a magnetic head and a magnetic recording medium as close to zero as possible. For example, Journal of The Magnetic Society of Jap
an Vol. 18, Supplement, No. S1 (1994),
Hamilton et al. Adopted a method of supporting a magnetic head with a light load to reduce frictional force. As a result, an attempt is made to make the distance between the magnetic head and the magnetic recording medium as close to zero as possible without causing the magnetic head to float and wear.

Further, for example, NIKKEI ELECTRONICS 199
As shown in 7.3.10 (No. 684) p141, Yanagisawa et al. Used the meniscus force of the lubricant to prevent the magnetic head and the magnetic recording medium from separating, and to keep the distance between the two endslessly.
Trying to make it.

However, both of these methods only consider making the distance between the magnetic head and the magnetic recording medium as close to zero as possible, and do not consider the recording bleeding phenomenon at all. Therefore, even if either of the above methods is adopted, it is necessary to further provide some treatment for recording blurring. In addition to these two methods, generally, the method of making the distance between the magnetic head and the magnetic recording medium close to 0 does not take care of the recording bleeding, and may rather cause the recording bleeding phenomenon to be larger. .

On the other hand, a method for removing recording blur is to make the reproducing track width of the reproducing head smaller than the recording track width of the recording head, that is, to make the phases recorded in the area 121 in FIG. 30 uniform. Some attempt to reproduce only the signal that is playing. In this method, when the magnetic head of the magnetic recording device is positioned slightly inclined with respect to the recording track and the skew of the head is taken into consideration, the reproducing track width of the reproducing head must be about half of the recording track width of the recording head. Have to be. In this,
Only about half of the recorded information signal contributes to reproduction, and waste is increased. However, there is no method other than the above-described method that controls so as not to reproduce the recording blur and prevents the deterioration of the signal quality. Therefore, at present, many magnetic disk manufacturers adopt the above-described method as a method of removing recording blur.

However, although the recording blur can be removed by this method of removing the recording blur, no measure is taken for reducing the distance between the magnetic head and the recording medium to zero as much as possible. Therefore, in order to effectively apply the method to a perpendicular magnetic recording method using a single-layer film medium, in addition to the method of removing the recording bleeding, there is no need to use a method of making the distance between the magnetic head and the medium as close to zero as possible. must not.

As described above, in the conventional method, in order to effectively adopt the perpendicular magnetic recording method using the single-layer film medium, the distance between the magnetic head and the recording medium is made infinitely zero; It is necessary to simultaneously introduce two new techniques, that is, a technique for removing recording blur. Therefore, the magnetic disk drive becomes complicated and may increase the cost.

Accordingly, the present invention has been proposed in view of such circumstances. The distance between the magnetic head and the magnetic disk can be reduced to zero as much as possible, and the recording blur can be eliminated. It is another object of the present invention to provide a magnetic recording medium and a magnetic recording apparatus which can effectively adopt a perpendicular magnetic recording method despite having a single-layer film structure and can realize higher density recording.

[0044]

According to the magnetic recording medium of the present invention which achieves the above object, an information signal is recorded by a recording head mounted on a head slider which at least partially floats during recording. A magnetic recording medium, wherein a magnetic layer having perpendicular magnetic anisotropy is formed on a substrate, a predetermined concavo-convex pattern is formed on the surface of the medium, and the recording head in a convex portion of the predetermined concavo-convex pattern A width dimension in a direction perpendicular to the traveling direction of the recording head is not more than a recording track width dimension of the recording head, and an information signal is recorded on the convex portion by the recording head by a perpendicular magnetic recording method. Things. Here, the magnetic recording medium according to the present invention has a single-layer film structure in which the high magnetic permeability layer is not formed on the substrate and the magnetic layer is formed.

As described above, the magnetic recording medium according to the present invention has a single-layer film structure in which a magnetic layer is formed on a substrate without providing a high magnetic permeability layer, and a predetermined uneven pattern is formed on the medium surface. The width dimension of the protrusions of the uneven pattern formed in the direction orthogonal to the running direction of the recording head is equal to or less than the recording track width dimension of the recording head.

Therefore, in the magnetic recording medium of the present invention, an information signal is applied to the magnetic recording medium by a magnetic field from a place other than the recording track width of the recording head, that is, from a side surface of the recording head not facing the magnetic recording medium. The information signal is accurately recorded only in the area of the magnetic recording medium facing the recording track width of the recording head without being written. That is, in the magnetic recording medium of the present invention, there is no area in which the recording blur is written, and as a result, the recording blur is eliminated.

In the magnetic recording medium according to the present invention, at the time of recording / reproducing, a levitation force acts on the head slider due to the air flow entering the gap between the recess formed on the medium surface and the head slider. At this time, at least a part of the head slider flies from the concave portion of the magnetic recording medium of the present invention by a predetermined flying height due to the floating force.

Therefore, in the magnetic recording medium of the present invention, the head slider flying above the medium has a flying height equivalent to that of a conventional head slider flying above a flat magnetic recording medium. However, the distance between the protrusion formed on the magnetic recording medium of the present invention and the head slider becomes closer. Further, by further reducing the flying height of the head slider, in the magnetic recording medium of the present invention, the distance between the protrusion on the medium and the head slider can be made as close to zero as possible.

Therefore, in the magnetic recording medium of the present invention, even if the magnetic recording medium has a single-layer film structure in which the high magnetic permeability layer for intensively distributing the perpendicular magnetic field is not provided, the head slider and the convex portion of the magnetic recording medium can be separated. Since the distance can be made as close as possible to 0, a sufficient perpendicular magnetic field can be applied to this convex portion by using a magnetic head that has been widely used, and an information signal is effectively recorded by a perpendicular magnetic recording method. be able to.

As described above, in the magnetic recording medium of the present invention, the perpendicular magnetic recording system can be employed, so that the thermal fluctuation phenomenon which is a problem in the longitudinal magnetic recording system can be avoided.

Since the magnetic recording medium of the present invention has a structure in which the high magnetic permeability layer is not provided, a problem caused by the high magnetic permeability layer, for example, the rigidity of the medium itself is increased. The problem of being difficult to handle and the problem of generating noise due to the movement of the domain wall in the high magnetic permeability layer are also solved.

Further, in the magnetic recording apparatus according to the present invention, at least one magnetic recording medium having a magnetic layer having perpendicular magnetic anisotropy formed on a substrate and having a predetermined uneven pattern formed on the surface is provided. A recording head for recording an information signal by a perpendicular magnetic recording method on a convex portion of a predetermined concavo-convex pattern formed on the surface of the magnetic recording medium, mounted on the head slider, and It is provided with.

In the magnetic recording apparatus according to the present invention, the magnetic recording medium may be configured such that a width dimension of a convex portion of the predetermined concavo-convex pattern in a direction perpendicular to a traveling direction of the recording head is equal to the width of the recording head. Is smaller than the recording track width dimension.

As described above, according to the magnetic recording apparatus of the present invention, the predetermined concave / convex pattern is formed on the surface of the magnetic recording medium, and the width of the convex portion of the concave / convex pattern is determined by the recording track width of the recording head. Because of the following, due to a magnetic field from a place other than the recording track width of the recording head, that is, from a side surface not facing the magnetic recording medium of the recording head,
No information signal is written on the magnetic recording medium.

That is, according to the magnetic recording apparatus of the present invention,
There will be no area where the recording blur will be written,
As a result, it is possible to eliminate recording blur.

In the magnetic recording apparatus according to the present invention, at the time of recording / reproducing, a levitation force acts on the head slider by an air flow entering a gap between the recess formed on the surface of the magnetic recording medium and the head slider. At this time, at least a part of the head slider floats from the concave portion of the magnetic recording medium by a predetermined floating amount due to the floating force.

Therefore, in the magnetic recording apparatus of the present invention, the head slider flying above the magnetic recording medium is flying with the same flying height as the conventional head slider flying above the flat magnetic recording medium. Even in this case, the distance between the protrusion on the magnetic recording medium and the head slider becomes shorter. Further, by further reducing the flying height of the head slider, in the magnetic recording apparatus of the present invention, the distance between the protrusion on the magnetic recording medium and the head slider is reduced to 0 without limit.
Can be approached.

Therefore, according to the magnetic recording medium device of the present invention, even if the magnetic recording medium has a single-layer structure in which the high magnetic permeability layer for intensively distributing the perpendicular magnetic field is not provided, the head slider and the magnetic recording medium can be used. Since the distance from the convex portion of the recording medium can be made as close as possible to zero, a sufficient perpendicular magnetic field can be applied to the convex portion using a magnetic head that has been widely used, and the information can be read by the perpendicular magnetic recording method. Signals can be recorded effectively.

As described above, in the magnetic recording apparatus of the present invention, the perpendicular magnetic recording system can be employed, and thus the thermal fluctuation phenomenon which is a problem in the longitudinal magnetic recording system can be avoided.

[0060]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, specific embodiments of the present invention will be described in detail with reference to the drawings. In the following, as a magnetic recording medium to which the present invention is applied,
Although a magnetic disk is taken up, the magnetic recording medium to which the present invention is applied is not limited to this, and may be any as long as a magnetic layer having perpendicular magnetic anisotropy is formed on a substrate. A magnetic tape or the like having a configuration may be used. FIG. 1 is a perspective view of a magnetic disk drive to which the present invention is applied.

In the magnetic disk drive 1 of the present invention, a spindle motor 9 is disposed on the back side of the plane portion of the housing 2 formed of an aluminum alloy or the like, and is rotated at a constant angular velocity by the spindle motor 9. The magnetic disk 3 of the present invention is provided. Further, an arm 4 is attached to the housing 2 so as to be swingable around a vertical axis 4a. A voice coil motor 7 is attached to one end of the arm 4, and a head slider 6 is attached to the other end of the arm 4.

The voice coil motor 7 includes a cover yoke 7
a, a bottom yoke 7b, a voice coil 5, and a magnet 7c. The cover yoke 7a and the bottom yoke 7b are formed so as to sandwich the voice coil 5 and the magnet 7c. Also, the magnet 7c
It is mounted on the bottom yoke 7b.

FIG. 2 is a schematic diagram showing a state where the head slider 6 is flying above the magnetic disk 3 of the present invention.

As shown in FIG. 2, the magnetic disk 3 of the present invention has a substrate 13 having a predetermined uneven pattern formed on the surface.
The magnetic film 14 is formed thereon. On the surface of the magnetic disk 3, an uneven pattern corresponding to the recording tracks on the substrate 13 is formed in a direction parallel to the running direction of the head slider 6. Here, these concavo-convex patterns are formed concentrically on the surface of the magnetic disk 3. When the recording track of the magnetic disk 3 is formed in a spiral shape, these concavo-convex patterns are formed in a spiral shape along the recording track.

The magnetic disk of the present invention may have a structure in which magnetic films are formed on both main surfaces of the substrate on which the concavo-convex pattern is formed.

The head slider 6 is, as shown in FIG.
Rails 6a and 6b functioning as air bearing surfaces are formed on both sides of the lower surface, and tapered portions 6c and 6d are formed on the distal ends of the rails 6a and 6b.

Then, on the rear end face of one of the rails 6a,
A magnetic head 8 is mounted. This magnetic head 8
Any magnetic head capable of performing a perpendicular magnetic recording method on a single-layer film medium may be used, and examples thereof include a ring-type head and a thin-film magnetic head. As a reproducing head, a magnetic head such as a magnetoresistive head may also be mounted on the head slider 6.

FIG. 2 shows a state in which the head slider 6 and the magnetic head 8 are flying above the magnetic disk 3. However, in the magnetic disk device 1 of the present invention, as will be described later, recording and reproduction are performed. At times, the convex portion 3 a on the surface of the magnetic disk 3 is in contact with the magnetic head 8.

In the magnetic disk drive 1 having the above-described configuration, first, when the spindle motor 9 is driven to rotate, the magnetic disk 3 rotates at a predetermined speed with the rotation of the spindle motor 9. When an external current is supplied to the voice coil 5, the arm 4 rotates around the vertical axis 4 a based on the force generated by the magnetic fields of the magnets 7 a and 7 b and the current flowing through the voice coil 5. Move. As a result, the head slider 6 attached to the other end of the arm 4 travels on the surface of the magnetically driven magnetic disk 3 while moving on the surface of the magnetic disk 3.
Move in a substantially radial direction. And this gives
The magnetic head 8 mounted on the head slider 6 performs a seek operation on the magnetic disk 3.

At this time, with the rotation of the magnetic disk 3, air flows in from the tapered portions 6c and 6d on the tip side of the rails 6a and 6b of the head slider 6. This air flows between the head slider 6 and the magnetic disk 3 along the rails 6a and 6b. The head slider 6 receives the levitation force from the surface of the concave portion 3b of the magnetic disk 3 and flies at a small flying height by the airflow. That is, the head slider 6 is mounted on the magnetic disk 3
The gap with the surface of the magnetic disk 3 is designed to decrease from the leading end to the trailing end with respect to the running direction, and a levitation force is obtained by the airflow flowing through the gap to move the surface of the magnetic disk 3 over the surface. Levitating with low flying height.

If there is no gap between the head slider 6 and the surface of the magnetic disk 3, the head slider 6
Since no air flows between the magnetic disk 3 and the magnetic disk 3, the head slider 6 does not float, and the magnetic head 8 and the magnetic disk 3 come into complete contact. In this case, since the load of the head slider 6 is applied to the magnetic disk 3, the friction between the magnetic head 8 and the magnetic disk 3 at the time of recording / reproducing causes a problem of wear of the magnetic head 8 and the magnetic disk 3. Would.

On the other hand, in the magnetic disk 3 of the present invention, FIG.
As shown in FIG. 4 and FIG. 4, since a predetermined uneven pattern is formed on the surface of the magnetic disk 3, a minute gap is formed between the concave portion 3b of the magnetic disk 3 and the rear end side of the rails 6a and 6b of the head slider 6. The air flows through. The air flow causes a levitation force to act on the head slider 6, and the gap between the head slider 6 and the convex portion 3a of the magnetic disk 3 approaches zero as much as possible while maintaining the floating state between the magnetic disk 3 and the head slider 6. Up to this point, the flying height of the head slider 6 can be reduced.

In other words, in the magnetic disk 3 of the present invention, the head slider 6 flying above the medium floats at the same flying height as the conventional head slider flying above the magnetic recording medium having a flat surface. In this case, the distance between the protrusion 3a formed on the magnetic disk 3 of the present invention and the head slider 6 is further reduced. By further reducing the flying height of the head slider 6,
In the magnetic disk 3 of the present invention, the distance between the protrusion 3a on the medium and the head slider 6 can be made as close as possible to zero.

Therefore, in the magnetic disk 3 of the present invention, even if the head slider 6 and the protrusion 3a of the magnetic disk 3 have a single-layer film structure in which the high magnetic permeability layer for intensively distributing the perpendicular magnetic field is not provided. Can be made as close as possible to zero, a sufficient perpendicular magnetic field can be applied to the convex portion 3a using a magnetic head that has been widely used, and an information signal can be effectively transmitted by the perpendicular magnetic recording method. Can be recorded.

Further, in this magnetic disk 3,
By minimizing the flying height of the head slider 6, the magnetic head 8 can be finally brought into contact with the projection 3a of the magnetic disk 3 without load. Thereby, even if the magnetic head 8 and the surface of the magnetic disk 3 are in contact, the magnetic head 8 and the magnetic disk 3
Can be completely prevented.

That is, in such a head slider 6 and the magnetic disk 3, the magnetic head 8 is
The air flow flowing along the rails 6a, 6b from the tapered portions 6c, 6d when coming into contact with the convex portion 3a of the magnetic disk 3 flows out of a minute gap between the concave portion 3b of the magnetic disk 3 and the rear end side of the rails 6a, 6b. Therefore, as shown in FIG. 4, a levitation force N1 is generated on the head slider 6 in the direction in which the head slider 6 flies. Therefore, if the levitation force Nl and the load N2 of the head slider 6 are balanced, the normal reaction L from the projection 3a of the magnetic disk 3 applied to the magnetic head 8 is reduced to zero, and The frictional force between the magnetic disk 3 and the surface of the magnetic disk 3 can be reduced to zero, and the protrusion 3a of the magnetic disk 3 can be brought into contact with the magnetic head 8 without load. Wear can be eliminated.

However, in the magnetic disk 3 of the present invention,
As shown in FIG. 4, it is an ideal state that the surface convex portion 3a and the magnetic head 8 are brought into contact with each other with no load, and the surface convex portion 3a and the magnetic head 8 are completely contacted. Even if they are not in contact with each other, the distance between the head slider 6 and the convex portion 3a can be made as close as possible to zero as described above in the magnetic disk 3 of the present invention. An information signal can be effectively recorded by the recording method.

In particular, in the magnetic disk 3 of the present invention, the width dimension of the convex portion 3a of the above-mentioned predetermined concavo-convex pattern formed on the disk surface in the direction orthogonal to the running direction of the recording head is set to be equal to the width of the recording head. The recording track width of the head is smaller than the dimension.

That is, in the magnetic disk 3 of the present invention, the width dimension of the convex portion 3a is substantially the same as the recording track width dimension of the recording head to be used, or a slight deviation in track position occurs due to servo. It is to narrow.

FIG. 5 shows the relationship between the width of the projection 3a formed on the surface of the magnetic disk 3 of the present invention in the direction perpendicular to the direction in which the recording head 8a runs, and the recording track width of the recording head 8a. FIG. Here, a direction perpendicular to the traveling direction of the recording head 8a of the raised portion 3a formed on the surface of the magnetic disk 3, i.e. a substantially radial width dimension of the disc as W _1, the recording track width of the recording head 8a the size and W _2.

That is, in the magnetic disk 3 of the present invention,
As shown in FIG. 5, the width W ₁ of the convex portion 3a, the relationship between the recording track width W ₂ of the recording head 8a, W ₁
A ≦ W _2.

As described above, in the magnetic disk 3 of the present invention, the width W ₁ of the projection 3a formed on the surface is smaller than the width W ₂ of the recording track of the recording head 8a. No information signal is written to the magnetic disk 3 by a magnetic field from a place other than the recording track width of the recording head 8a, that is, a side surface of the recording head 8a that is not opposed to the magnetic disk 3, and the recording track of the recording head 8a The information signal is accurately recorded in the area on the magnetic disk 3 opposite to the width.

That is, in the magnetic disk 3 of the present invention,
There will be no area where the recording blur will be written,
It is possible to eliminate recording blur. As a result, in the magnetic disk 3 of the present invention, the track width can be reduced, so that the track density can be further improved, and the linear density of each track can also be more easily improved, thereby further increasing the track height. It is possible to realize density recording.

Next, the structure of the magnetic disk 3 of the present invention as described above will be described in more detail. FIG.
1 is a plan view showing a magnetic disk 3 to which the present invention is applied. FIG. 7 is an enlarged plan view showing a range X in FIG. 6 in an enlarged manner. 8 is a sectional view of the magnetic disk 3 in the radial direction, and FIG. 9 is a sectional view of the magnetic disk 3 in the track direction.

The substrate 13 of the magnetic disk 3 is made of synthetic resin, glass, aluminum or the like. The substrate 13 has a predetermined uneven pattern corresponding to each of a data recording area (data zone) 30 and a control signal recording area (servo zone) 31, and a magnetic film 14 is formed on the surface. I have. The data zone 30 and the servo zone 31 are positioned such that the servo zone 31 appears at predetermined intervals during recording and reproduction, for example, as shown in FIGS. It is formed so as to be substantially radial from the center.

In the data zone 30, data tracks for recording arbitrary data and guard bands for separating adjacent data tracks are formed concentrically. Then, on the magnetic disk 3, as shown in FIGS. 7 and 8, the data track becomes a convex portion 3a,
Irregularities are formed so that the guard band becomes the concave portion 3b. Note that these irregularities may be parallel to the traveling direction of the head slider 6. For example, when a recording track is formed in a spiral shape, the recording track is formed in a spiral shape along the recording track. In addition, these irregularities may be formed so that the convex portions 3a may be continuously continuous in the circumferential direction, or may be divided to such an extent that the traveling of the head slider 6 is not adversely affected.

On the other hand, the servo zone 31 includes a gray code for specifying a data track, a clock mark serving as a reference when generating a servo clock, a wobbled mark used for tracking control of the magnetic head 8, and the like. Are recorded. Here, in the servo zone 31, irregularities as shown in FIGS. 7 and 9 are formed, and the convex portions 3a and the concave portions 3b are magnetized in directions opposite to each other, whereby the servo pattern is recorded. I have.

The magnetic disk 3 having the above configuration
Are manufactured, for example, using optical technology. An example of the manufacturing method will be described with reference to FIGS.

As shown in FIG. 10, first, the glass master 4
For example, a photoresist 42 is coated on the surface of the substrate 1, and the glass master 41 coated with the photoresist 42 is placed on a dinner table 43 and rotated to form a recess in the photoresist 42. The pattern cutting is performed by irradiating the laser beam 44 only on the portion 42. At this time, the laser cutting is performed so that the width dimension in the disk radial direction of the convex portion generated between the concave portions formed by the laser cutting is equal to or less than the recording track width dimension W ₂ of the recording head used in the magnetic disk device 1. Do.

Next, the exposed portion of the photoresist 42 is removed by developing the photoresist 42 as shown in FIG. At this time, the width W ₁ of the disk radial direction of the convex portion of the photoresist 4 remaining is equal to or less than the recording track width W ₂ of the recording head.

Next, as shown in FIG. 12, the surface of the glass master 41 from which the exposed portions of the photoresist 42 have been removed is plated with nickel 45. Then, as shown in FIG. 13, the nickel 45 is peeled off from the glass master 41 to form a stamper 46.

Here, the concave shape of the stamper 46 is transferred as the convex shape of the substrate 13 formed using the stamper 46. Therefore, the width of the concave portion of the stamper 46 in the disk radial direction is substantially the same as the width of the convex portion formed on the disk surface in the disk radial direction. Therefore, the width of the disk radial direction of the recesses of the stamper 46 becomes less recording track width W ₂ of the recording head.

Next, as shown in FIG. 14, for example, the stamper 46 is joined to the molding surface of the molding die 47, and the substrate 13 is molded using the molding die 47. Then, as shown in FIG. 15, the magnetic film 1 is formed on the surface of the obtained substrate 13.
4 is formed by sputtering or the like to obtain a magnetic disk 3 as shown in FIG.

Thereafter, a magnetizing device 47 as shown in FIG.
The magnetic disk 3 is magnetized by the magnetic head 48 for magnetizing. When magnetizing the magnetic disk 3, the magnetic disk 3
Is set in the magnetizing device 47 and, for example, as shown in FIG. 18, while supplying the first DC current to the magnetizing magnetic head 48, the magnetizing magnetic head 48 is moved in the radial direction a of the magnetic disk 3. By moving the magnetic film 14 at a predetermined track pitch, the magnetic films 14 of the convex portions 3a and the concave portions 3b of the magnetic disk 3 are all magnetized in the same direction.

Thereafter, as shown in FIG. 19, a second DC current having a polarity opposite to that of the first DC current and having a smaller current value than the first DC current is applied to the magnetizing magnetic head 48. While applying the voltage, the magnetizing magnetic head 48 is moved at a track pitch in the radial direction a on the magnetic disk 3 so that only the magnetic film 14 of the convex portion 3a of the magnetic disk 3 is magnetized in the opposite direction, and the wobbled mark is formed. And write servo patterns such as clock marks.

The method of manufacturing the magnetic disk 3 may be, for example, a method of forming the magnetic film 14 on the substrate 13 and then etching the magnetic film 14 to obtain desired unevenness. There is also a method of forming

FIG. 20 is a block diagram showing an example of the configuration of the control unit of the magnetic disk device 1 having the magnetic disk 3 as described above. Here, it is assumed that the magnetic head 8 comprises a recording head 8a used exclusively for recording and a reproducing head 8b used exclusively for reproduction.

The clock signal generation unit 11 of the control unit 10
It receives a signal reproduced by the reproducing head 8b from the magnetic disk 3 rotated and driven by the spindle motor 9, generates a clock signal from the signal, and outputs the clock signal to the tracking servo unit 12 and the reproducing unit 13. The tracking servo unit 12 generates a tracking error signal based on a signal supplied from the reproducing head 8b with reference to the clock signal from the clock signal generation unit 10a, and drives the arm 4 in response to the tracking error signal. Thus, tracking control is performed so that the recording head 8a and the reproducing head 8b are at predetermined radial positions on the magnetic disk 3. The recording unit 14 modulates a recording signal supplied from an external circuit (not shown), and records the recording signal on the magnetic disk 3 via the recording head 8a. on the other hand,
The reproduction unit 13 demodulates a reproduction signal from the reproduction head 8b and outputs the demodulated signal to an external circuit (not shown). Further, the tracking servo unit 12 monitors the tracking error signal. For example, when a large shock or the like is applied to the hard disk drive 1 and the recording head 8a separates from the recording track and enters an off-track state, The recording unit 14 is controlled to stop the recording operation.

Next, a description will be given of experimental results of a trial production of the magnetic disk device as described above with the disk surface shape of the magnetic disk 3 changed.

<Example 1> First, the following disk substrate was manufactured in order to evaluate a change in the flying height and a change in the flying state of a head slider by forming a predetermined uneven pattern on the surface of a magnetic disk.

FIG. 21 is a plan view of the measuring disk 20. FIG. 22 is an enlarged plan view of the range Y in FIG. FIG. 23 shows an outline of the measurement system.

As the measurement disk 20, a glass disk made of glass as shown in FIGS. 21 and 22 was prepared. The concave and convex portions are regularly and concentrically formed on the glass disk. The width of the concave portion is 1.0 μm, and the width of the convex portion is 2.0 μm. The concentric pattern of the concave portion and the convex portion is formed in an area having a radius of 15.5 mm to 35.0 mm of the glass disk. A flat area for measuring the flying height of the head slider 21 has a width of about 0. 0 near the center of this pattern.
It is formed with 4 mm.

When preparing such a measuring disk 20, a resist was first applied to the surface of a glass disk, and an uneven pattern was exposed on the resist based on cutting data. Next, after this exposure, for example, R
An uneven pattern was formed by IE (reactive ion etching).

As the measurement slider 21, a general two-rail taper flat nano-slider was used. Slider length is 2.0mm, slider width is 1.6m
m, the rail width was 200 μm, and the load was 3.5 gf.
In addition, an intermediate portion between the rails, that is, the measuring slider 2
A measurement rail having a width of 10 μm was provided on the center line of No. 1.
Since the measurement rail is sufficiently thinner than the two rails on both sides, it hardly affects the flying of the measurement slider 21.

In the measuring system as shown in FIG. 23, the flying height until the measuring slider 21 comes into contact with the surface of the measuring disk 20 is measured by a commercially available flying height measuring instrument utilizing optical interference. Further, the frictional force applied to the measurement slider 21 when the measurement slider 21 contacts the surface of the measurement disk 20 is measured by a strain gauge 23 mounted on the load beam 22.

Then, in such a measurement system, the measurement was performed as described below using the measurement slider 21 and the measurement disk 20.

First, the measuring disk 20 was rotated at a rotation speed at which the measuring slider 21 flies sufficiently. After that, a flying height measuring beam from a commercially available flying height measuring instrument utilizing optical interference is applied to the measuring slider 21 through the flat area of the measuring disk 20, and the returned light is detected to perform measurement. While measuring the flying height of the slider 21 for measurement, the rotation speed of the measurement disk 20 was gradually reduced. Then, the measurement slider 21 is moved to the measurement disk 20.
The flying height of the measuring slider 21 was measured until the slider came into contact with the surface of the measuring disk 20, and the output of the strain gauge 23 before and after the measuring slider 21 contacted the surface of the measuring disk 20 was measured. The rotation of the measuring disc 20 includes
Servo was applied so that the number of revolutions of the measuring disk 20 was accurately developed with time. Then, the rotation speed of the measurement disk 20 is calculated based on the time from the start of the measurement,
The flying height of the measurement slider 21 and the output of the strain gauge at a predetermined rotation speed were measured.

As described above, the relationship between the number of revolutions of the measuring disk 20 and the flying height of the measuring head slider 21 was determined.
FIG. 24 shows the result of examining the relationship between the rotation speed of the measuring disc 20 and the output of the strain gauge 23. In FIG. 24, the horizontal axis indicates the number of rotations of the measurement disk 20, and the vertical axis indicates the flying height of the measurement slider 21 and the output of the strain gauge 23.

As shown in FIG. 24, the measuring slider 21
Of the measurement disk 20 is 3000 r.
pm, it was 15 nm, but as the rotation speed gradually decreased, the flying height decreased linearly, and the rotation speed became 25 nm.
In the vicinity of 00 rpm, the flying height is about 5 nm, and the number of rotation is 2
At 500 rpm or less, the flying height starts to be disturbed. The output of the strain gauge 23 is 0 when the rotational speed of the measuring disk 20 is from 3000 rpm to around 2500 rpm.
However, the output starts to be output at a rotation speed of 2500 rpm or less, and the output is saturated at a rotation speed of 2200 rpm.

The flying height of the measurement slider 21 measured was:
This is a standard flying height for a head slider for a magnetic disk drive. From the results shown in FIG. 24, the fact that the measurement slider 21 starts to contact the surface of the measurement disk 20 is actually caused by the fluctuation of the flying height of the measurement slider 21 or the glide height of the measurement disk 20. Taking this into account, the rotational speed of the measuring disc 20 is approximately 250
It can be said that it is at 0 rpm.

That is, when the rotational speed of the measuring disk 20 is higher than 2500 rpm, the load of the measuring slider 21 is almost supported by the pressure of the air flowing into the gap between the measuring slider 21 and the measuring disk 20. I have.
However, the rotation speed of the measurement disk 20 is 2500 rpm
m, the load of the measurement slider 21 cannot be supported only by the levitation force caused by the airflow flowing between the measurement slider 21 and the concave portion of the measurement disk 20, and the measurement slider 21 has the levitation force. And the convex portion of the measuring disk 20. Further, when the rotation speed of the measuring disk 20 becomes 2200 rpm or less, the load of the measuring slider 21 is almost supported by the convex portion of the measuring disk 20.

As described above, when the rotation speed of the measurement disk 20 is around 2500 rpm, the measurement slider 21 and the measurement disk 20 are in contact with each other, and the load of the measurement slider 21 is It can be seen that it is supported by the buoyancy by the airflow flowing into the gap with the measuring disk 20. That is, by setting the rotation speed of the measurement disk 20 to around 2500 rpm, the magnetic head mounted on the measurement slider 21 can be brought into contact with the measurement disk 20 without load, that is, the flying height of the magnetic head is substantially reduced. Can be zero.

<Example 2> Next, in order to evaluate the magnetization pattern when an information signal was recorded by a perpendicular magnetic recording method using a magnetic disk having a single-layer film structure, the following magnetic disk was manufactured. .

First, a glass disk having the same structure as that used in Example 1 was prepared. Next, a magnetic layer having perpendicular magnetic anisotropy was formed on the glass disk by sputtering using a magnetic material composed of CoCrTa. Then, a lubricant was applied on the magnetic layer to produce a magnetic disk for measurement.

Then, recording and reproduction of information signals were performed on the manufactured magnetic disk using a magnetic head under the following conditions.

Here, a thin-film head was used as the recording head used in this experiment. The thin film head used had a gap length of 0.2 μm and a recording track width of 2.2 μm. As described above, in this embodiment, the width of the protrusion formed on the magnetic disk is made slightly smaller than the recording track width of the recording head.

As a reproducing head, a magneto-resistance effect type magnetic head was used. As the magnetoresistive head, a magnetic head having a shield interval of 0.3 μm was used.

Such a recording head and a reproducing head are
The flying slider used in Example 1 was mounted on the rear end.

The number of rotations of the disk at the time of recording and reproducing the information signal is 2600 rpm, which is slightly larger than 2500 rpm where the average flying height was 5 nm in the first embodiment.
And This is because when the rotational speed of the disk is 2500 rpm, as shown in FIG. 24, the flying height of the flying slider is disturbed, so that it is difficult to control the stable gap between the magnetic head and the recording medium.

Comparative Example A magnetic disk was prepared in the same manner as in Example 2 except that a normal flat glass disk having no irregularities on the magnetic disk was prepared for comparison.

Then, information signals were recorded / reproduced on the manufactured magnetic disk by using a thin film head and a magnetoresistive head having the same configuration as in the second embodiment.

The recording / reproducing slider 21 for recording / reproducing on a flat magnetic disk having no irregularities as in the comparative example is used for recording / reproducing on the magnetic disk 20 having irregularities as in the second embodiment. It is not feasible to levitate and run with a low flying height similar to that of a measurement slider when performing the measurement. Therefore, the flying height of the measuring slider 21 in this case is set to 50 nm so that the flying height of the measuring slider 21 can be ensured even on a flat magnetic disk as in this comparative example, and the recording / reproducing of the information signal is performed. Was done.

FIG. 2 is a schematic diagram of a magnetization pattern formed when an information signal is recorded by the recording head on the magnetic disks of Example 2 and Comparative Example manufactured as described above.
5 and FIG. 26, respectively. Such a magnetization pattern is obtained by a magnetic force microscope (MF).
M).

In the second embodiment, irregularities having a width smaller than the recording track width of the recording head are formed, and information signals are recorded on the convexities. Example 2
As shown in FIG. 25, the magnetic disk 2 has no recording bleeding and information signals are recorded only on the convex portions 3a, and these information signals have no phase disorder.

On the other hand, the comparative example is a magnetic disk having a flat surface shape. In the magnetic disk of this comparative example, as shown in FIG. 26, both side portions 60a of the recording track width W ₂ of the recording head 8a, at 60b, a central portion 60c which faces the recording track width of the recording head 8a
In this case, a signal having a phase delayed from that of the information signal recorded is recorded, that is, a recording blur phenomenon occurs.

In this embodiment, since no track positioning was performed, it was not always possible to perform recording on the convex portions over the entire circumference of the disk during recording.
Therefore, there was also a place where recording was performed on the convex portion in a state where the recording head was only half-float, and in such a case, recording bleeding was also observed on the convex portion. But,
This can be removed without any problem if the magnetic head tracks are accurately positioned.

From the above results, it is possible to form a predetermined uneven pattern on the disk surface, and to make the convex portion of the uneven pattern equal to or less than the track width of the recording head. It has been found that the bleeding phenomenon can be effectively removed from the magnetic disk.

Further, with respect to the magnetic disk of Example 2, information signals of various wavelengths were recorded on the convex portions formed on the disk surface, and were reproduced by the above-described magnetoresistive magnetic head. Was able to confirm that the signal quality was good.

Therefore, as shown from the above results, in the magnetic disk drive of the present invention, by forming the unevenness on the surface of the magnetic disk, the air flow entering the gap between the recess formed on the disk surface and the head slider As a result, a levitation force acts on the head slider, so that the magnetic head mounted on the head slider can be brought into contact with the convex portion without load.

As a result, in the magnetic disk drive of the present invention, the distance between the head slider and the magnetic disk can be made as close to 0 as possible, which is one of the problems when using the perpendicular magnetic recording method with a single-layer film medium. It was possible to solve the problem that the distance between the head slider and the magnetic disk was reduced to zero as much as possible. Therefore, in the magnetic disk device of the present invention, the distance between the head slider and the magnetic disk is infinite even if the magnetic disk has a single-layer film structure in which the high magnetic permeability layer for intensively distributing the perpendicular magnetic field is not provided. Since it is close to zero, a sufficient perpendicular magnetic field can be applied using a magnetic head that has been widely used, and the perpendicular magnetic recording method can be performed efficiently.

Further, since the magnetic disk drive of the present invention can employ the perpendicular magnetic recording system, it can be said that the thermal fluctuation phenomenon which is a problem in the longitudinal magnetic recording system can be avoided.

Moreover, in the magnetic disk drive of the present invention,
Since the width dimension of the convex portion of the concavo-convex pattern formed on the magnetic disk surface is set to be equal to or less than the recording track width dimension of the recording head, a portion other than the recording track width of the recording head,
That is, it has been found that the recording head can be prevented from recording bleeding without the information signal being written on the magnetic disk by the magnetic field from the side surface or the like not facing the magnetic disk of the recording head. Therefore, it can be said that the magnetic disk drive of the present invention can eliminate the recording blur phenomenon, which is another problem in the case of using the perpendicular magnetic recording method with a single-layer film medium.

[0133]

As described in detail above, according to the magnetic recording medium of the present invention, a predetermined concavo-convex pattern is formed on the surface of the medium, and the width of the convex portion of the concavo-convex pattern is determined by the recording head. Is smaller than the recording track width of
An information signal is not written on the magnetic disk by a magnetic field from a place other than the recording track width of the recording head, that is, from a side surface of the recording head not facing the magnetic disk.

That is, according to the magnetic recording medium of the present invention,
There will be no area where the recording blur will be written,
It is possible to eliminate recording blur. As a result, according to the magnetic recording medium of the present invention, a high-quality signal is recorded and reproduced, and high reliability is obtained. In addition, according to the magnetic recording medium of the present invention, the track width can be reduced, so that the track density can be further improved, and the linear density of each track can be more easily improved. High-density recording can be realized.

In the magnetic recording medium according to the present invention, at the time of recording / reproducing, a levitation force acts on the head slider due to the air flow entering the gap between the recess formed on the medium surface and the head slider. At this time, at least a part of the head slider flies from the concave portion of the magnetic recording medium of the present invention by a predetermined flying height due to the floating force.

Therefore, in the magnetic recording medium of the present invention, the head slider flying above the medium has a flying height equivalent to that of a conventional head slider flying above a flat magnetic recording medium. However, the distance between the protrusion formed on the magnetic recording medium of the present invention and the head slider becomes closer. Further, by further reducing the flying height of the head slider, in the magnetic recording medium of the present invention, the distance between the protrusion on the medium and the head slider can be made as close to zero as possible.

Therefore, in the magnetic recording medium of the present invention, even if the head slider has a single-layered film structure in which the high magnetic permeability layer for intensively distributing the perpendicular magnetic field is not provided, the head slider and the convex portion of the magnetic recording medium are formed. Since the distance can be made as close as possible to 0, a sufficient perpendicular magnetic field can be applied to this convex portion by using a magnetic head that has been widely used, and an information signal is effectively recorded by a perpendicular magnetic recording method. be able to.

As described above, since the magnetic recording medium of the present invention can employ the perpendicular magnetic recording method, the thermal fluctuation phenomenon which is a problem in the longitudinal magnetic recording method can be avoided.

On the other hand, in the magnetic recording apparatus according to the present invention, since the magnetic recording medium according to the present invention having the above-described configuration is built in, the distance between the magnetic head and the magnetic recording medium is reduced to zero as much as possible. In addition to the above, recording blur can be removed, the perpendicular magnetic recording method can be efficiently performed using a magnetic recording medium having a single-layer film structure, and a signal of good quality can be recorded and reproduced. High-density recording can be achieved.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a configuration example of a magnetic disk drive to which the present invention is applied.

FIG. 2 is a perspective view showing an example of a magnetic disk and a head slider to which the present invention is applied.

FIG. 3 is a perspective view showing a partial detailed example of a magnetic disk and a head slider to which the present invention is applied.

FIG. 4 is a cross-sectional view showing a force applied to a magnetic disk and a head slider to which the present invention is applied.

FIG. 5 is a sectional view of a main part of a magnetic disk and a magnetic head to which the present invention is applied.

FIG. 6 is a plan view of a magnetic disk to which the present invention is applied.

FIG. 7 is an enlarged plan view showing a range X in FIG. 6;

FIG. 8 is a sectional view in the radial direction of a magnetic disk to which the present invention is applied.

FIG. 9 is a sectional view in the track direction of a magnetic disk to which the present invention is applied.

FIG. 10 is a perspective view showing one step of a method for manufacturing a magnetic disk to which the present invention is applied.

FIG. 11 is a sectional view showing another step of the method for manufacturing a magnetic disk to which the present invention is applied.

FIG. 12 is a sectional view showing another step of the method for manufacturing a magnetic disk to which the present invention is applied.

FIG. 13 is a sectional view showing another step of the method for manufacturing a magnetic disk to which the present invention is applied.

FIG. 14 is a perspective view showing another step of the method for manufacturing a magnetic disk to which the present invention is applied.

FIG. 15 is a perspective view showing another step of the method for manufacturing a magnetic disk to which the present invention is applied.

FIG. 16 is a perspective view schematically showing a magnetic disk obtained by a method of manufacturing a magnetic disk to which the present invention is applied.

FIG. 17 is a plan view showing a magnetizing device used when manufacturing a magnetic disk to which the present invention is applied.

18 is a cross-sectional view showing one step of magnetizing a magnetic film of a magnetic disk using the magnetizing device shown in FIG.

19 is a cross-sectional view showing another process of magnetizing the magnetic film of the magnetic disk using the magnetizing device shown in FIG.

FIG. 20 is a block diagram illustrating a configuration example of a control unit of a magnetic disk drive to which the present invention has been applied.

FIG. 21 is a plan view showing a measurement disk used in this example.

FIG. 22 is an enlarged plan view showing a range Y in FIG. 21 in an enlarged manner.

FIG. 23 is a perspective view schematically showing a measurement system used in this example.

FIG. 24 is a diagram showing the results of this example.

FIG. 25 is a plan view showing a magnetization pattern in the magnetic disk of this example.

FIG. 26 is a plan view showing a magnetization pattern in a magnetic disk of a comparative example.

FIG. 27 is a sectional view showing an example of a conventional longitudinal magnetic recording system.

FIG. 28 is a sectional view showing an example of a conventional perpendicular magnetic recording system using a single-pole head.

FIG. 29 is a diagram showing a result of a relationship between a distance from a ring-shaped head and a strength of a magnetic field generated by the ring-shaped head obtained from a Westmize magnetic field calculation formula.

FIG. 30 is a plan view showing a magnetization pattern on a magnetic disk of a signal recorded on a conventional magnetic disk.

FIG. 31 is a plan view showing the degree of recording bleeding on a magnetic disk in the case of a perpendicular magnetic recording system using a single-pole head.

FIG. 32 is a plan view showing a degree of recording bleeding on a magnetic disk in the case of a longitudinal recording method using a ring-type head.

[Description of Signs] 1 magnetic disk device, 3 magnetic disk, 3a
Convex part, 3b concave part, 6 head slider, 8 magnetic head, 8a recording head, 13 substrate, 14
Magnetic film,

Claims (4)

[Claims] 1. A magnetic recording medium on which an information signal is recorded by a recording head mounted on a head slider that at least partially floats during recording, wherein the magnetic layer has perpendicular magnetic anisotropy on a substrate. A predetermined concavo-convex pattern is formed on the surface of the medium, and a width dimension of a convex portion of the predetermined concavo-convex pattern in a direction orthogonal to a traveling direction of the recording head is equal to a recording track of the recording head. A magnetic recording medium having a width not more than a width, wherein an information signal is recorded on the convex portion by the recording head by a perpendicular magnetic recording method. 2. The magnetic recording medium according to claim 1, wherein a high magnetic permeability layer is not formed on the substrate, and the magnetic recording medium has a single layer structure in which the magnetic layer is formed. 3. A magnetic recording medium in which a magnetic layer having perpendicular magnetic anisotropy is formed on a substrate, and a predetermined concave / convex pattern is formed on a surface of the magnetic recording medium. A head slider configured to fly, and a recording head mounted on the head slider and recording an information signal by a perpendicular magnetic recording method on a convex portion of a predetermined concavo-convex pattern formed on the surface of the magnetic recording medium. The magnetic recording medium is characterized in that a width of a convex portion of the predetermined concavo-convex pattern in a direction orthogonal to a running direction of the recording head is equal to or smaller than a recording track width of the recording head. Magnetic recording device. 4. The magnetic recording medium according to claim 3, wherein a high magnetic permeability layer is not formed on the substrate, and the magnetic recording medium has a single layer structure in which the magnetic layer is formed. Magnetic recording device.