JP2901437B2 - Magnetic disk and magnetic head - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic disk and a magnetic head having improved durability by stabilizing the flying and running of the magnetic head.

[0002]

2. Description of the Related Art In a disk-shaped magnetic disk (hard disk) used in a magnetic recording device of a computer or the like, signals are written and read by a magnetic head. In this type of magnetic recording device,
When the magnetic disk stops rotating, the magnetic head comes into contact with the surface of the magnetic disk, and when the magnetic disk rotates, the magnetic head floats due to the pressure of airflow generated on the surface of the magnetic disk, and floats above the magnetic disk. In this state, the magnetic head writes and reads signals to and from the rotating magnetic disk.

[0003] The stopped state and the flying traveling state of the magnetic head will be described in more detail. When the magnetic disk is started, the magnetic head is pressed against the surface of the magnetic disk by the spring pressure of the spring plate member supporting itself. When the magnetic disk starts rotating from this state, the magnetic head slides while being in contact with the rotating magnetic disk. Then, as the rotational speed of the magnetic disk increases, the lift due to the airflow generated on the surface of the magnetic disk increases, and when this lift overcomes the spring pressure on the magnetic head, the magnetic head gently flies above the surface of the magnetic disk. In addition, the magnetic head levitates relative to the magnetic disk while maintaining the flying height determined mainly by the shape and spring pressure of the magnetic head and the peripheral speed of the magnetic disk.

[0004]

In the magnetic disk and the magnetic head having the above structures, the magnetic head is moved from the start of rotation of the magnetic disk to the start of floating of the magnetic head.
The magnetic disk surface is rubbed while being suppressed by the spring pressure. For this reason, conventionally, the surface of the magnetic disk or the medium facing surface of the magnetic head is worn, and in some cases, the frictional force is abnormally increased, causing the surface breakdown (crash) of the magnetic head or the magnetic disk, and reading the recorded contents of the magnetic disk. I couldn't do anything. Further, when the frictional force between the magnetic head and the magnetic disk abnormally rises and the frictional force becomes a value equal to or larger than the rotational torque of the magnetic disk, the magnetic disk no longer rotates, which may lead to failure of the magnetic recording device.

In order to solve such a problem, conventionally,
The magnetic head slider is provided with a rail for flying and running, or an inclined surface is formed at the end of the rail to improve lift during flying and adopt a structure that allows the magnetic head to fly quickly. Is composed. However, even with such a configuration, there is still a possibility that the surface of the magnetic disk will be broken.

Further, in a magnetic recording apparatus composed of this magnetic disk and a magnetic head flying above the magnetic disk, the flying height of the magnetic head with respect to the magnetic disk is reduced, and spacing loss is further reduced. It is required to achieve high recording density. Therefore, conventionally,
High flatness and smoothness are required on the surface of the magnetic disk. On the other hand, a magnetic head is required to have flying stability, and in order to maintain the flying stability in good condition, a high flatness and smoothness are also required for the medium facing surface of the magnetic head. Therefore, in the conventional magnetic recording apparatus, the surface of the magnetic disk and the medium facing surface of the magnetic head are mirror-finished.

However, when the mirror-finished magnetic disk and the surface of the magnetic head come into contact with each other, the mirror surfaces attract each other, and as a result, the magnetic head is attracted to the magnetic disk and does not move. There is a problem that leads to a failure of the recording device. In particular, the surface of the magnetic disk subjected to mirror finishing and the medium facing surface of the magnetic head cause a strong adsorption phenomenon due to the lubricant applied to the magnetic disk and the medium facing surface of the magnetic head or moisture in the atmosphere. Had the problem that If the attraction force between the magnetic head and the magnetic disk exceeds the torque force of the drive rotation motor of the magnetic recording device due to the occurrence of the attraction phenomenon, start-up failure may occur.

Therefore, in order to solve the above-mentioned problems, a method of forming a rough surface of a medium facing surface of a magnetic head or a method of forming a groove called a texture along a circumferential direction on a surface of a magnetic disk is used. There is a method to prevent adsorption.
For example, a technique of providing a spiral groove (Japanese Patent Laid-Open No. 1-140)
422) and a technique of providing concentric grooves (see JP-A-56-35).

Here, the structure of a general magnetic disk having a texture will be described with reference to the drawings. FIGS. 44A and 44B show an example of a conventional magnetic disk. This magnetic disk is a disk-shaped substrate made of Al, Al alloy, glass, or the like, having a through hole 81 formed in the center. 82 and a coating film 83 made of Ni-P or the like coated on the entire surface of the substrate 82.
The laminated film 89 shown in FIG. 44B is formed on the covering film 83 of FIG.

[0010] In FIG. 44 (b), a laminated film 89 is composed of a base film 84 made of Cr having a thickness of about 150 nm and a base film 84.
The Co-Ni, Co-
Magnetic layer 85 made of Ni-Cr, Co-Cr-Ta, etc.
And a protective film 86 made of carbon having a thickness of about 30 nm laminated on the magnetic layer 85, and a lubricating film 87 coated on the protective film 86.

The coating film 83 made of Ni-P or the like is used.
Is processed to form a texture 88. In general, the texture 88 is formed by forming a large number of concavo-convex groove rings concentrically on the upper surface of the coating film 83, and the difference between the average roughness and the maximum height is zero. It is about 1 μm. And
Also on the surface of the laminated film 89 laminated on the coating film 83 on which the texture 88 is formed, a texture having a shape corresponding to the concave and convex grooves of the texture 88 formed on the coating film 83 is formed.

As a processing method of the texture 88, there is a method of pressing a polishing tape, in which abrasive grains are specially adjusted, with a proper pressure against a substrate rotating at a constant angular velocity.

The formation of the texture 88 reduces the contact area between the magnetic head in contact with the magnetic disk and the surface of the magnetic disk, and reduces the adsorption phenomenon between the medium facing surface of the magnetic head and the surface of the magnetic disk. There is an effect of doing. In addition to the above-mentioned effects, the texture 88 gives magnetic anisotropy to the magnetic layer 85 coated on the surface, and has a high coercive force in the circumferential direction which is convenient for magnetic recording. In addition, it is possible to provide a magnetic disk having excellent resolution and low DC erasing noise.

Therefore, when the rotation of the magnetic disk is stopped, the magnetic head comes into contact with the magnetic disk, and when the magnetic disk is rotated, the magnetic head is separated from the magnetic disk (contact start / stop: hereinafter referred to as CSS). Has two functions of preventing the magnetic head from sticking to the medium facing surface of the magnetic head and the surface of the magnetic disk, and increasing the coercive force using magnetic anisotropy for high-density recording. At this time, it is preferable that the texture is rough in order to prevent the magnetic head from sticking to the medium facing surface and the surface of the magnetic disk, but in order to increase the flying stability of the magnetic head and obtain stable electromagnetic characteristics, And a uniform texture is preferred.

In recent years, as the development of higher performance magnetic recording devices has progressed, to achieve higher density recording,
As the flying height of the magnetic head has been reduced, emphasis has been placed on the flying stability of the magnetic head in order to cope with this flying height, and together with the remarkable progress in processing technology for finer and uniform texture, As for the texture of the disk, miniaturization and uniformity have become indispensable factors. On the other hand, the miniaturization and uniformity of the texture reduce the function of suppressing the adsorption phenomenon between the surface of the magnetic disk and the medium facing surface of the magnetic head. In addition, there is a problem that the conflicting problem of reducing the adsorption phenomenon between the magnetic disk surface and the medium facing surface of the magnetic head must be solved together.

Therefore, in order to avoid such a problem,
A magnetic disk has been proposed in which a coarse texture is provided in a portion other than a portion where a magnetic head of a magnetic disk floats, that is, a portion where a CSS operation is performed, and a fine and uniform texture is provided in a portion where data is recorded and reproduced. Was. However, such a magnetic disk can cope with a low flying height of the magnetic head to some extent,
Even in the CSS operation portion provided with a rough texture, the magnetic head runs at a low flying height, so that the magnetic disk surface and the medium facing surface of the magnetic head due to unstable floating running of the magnetic head are unavoidable and stable. However, there is an essential drawback that the resulting magnetic properties are impaired. As a magnetic recording device, a magnetic disk and a magnetic head having a durability performance capable of withstanding at least 30,000 CSS operations have been desired.

Further, since the magnetic disk rotates at a constant speed, a difference occurs in the peripheral speed of the magnetic disk between the inner peripheral portion and the outer peripheral portion of the surface. Differences occur depending on the location.
That is, the flying height of the magnetic head tends to be low at the inner peripheral portion of the magnetic disk surface and higher at the outer peripheral portion thereof. Since the recording magnetic field of the magnetic head and the leakage magnetic field of the magnetic disk become smaller according to the distance between the magnetic head and the magnetic disk, the flying height of the magnetic head changes on the inner and outer peripheral sides of the surface of the magnetic disk. This is disadvantageous in performing stable and accurate magnetic recording and reproduction.

In order to solve such a problem, a magnetic head is conventionally provided with an inclination called a skew angle to face a magnetic disk, and a center line of the magnetic head and a magnetic disk are provided at an inner peripheral portion of the surface of the magnetic disk. Are provided so that the relationship between the peripheral speed and the flying height is changed by making the tangential directions coincide with each other and shifting the tangential direction toward the outer periphery. However, the flying height of a normal magnetic head is 0.1 to 0.1.
Making the flying height of the magnetic head the same on the inner peripheral side of the magnetic disk surface due to the skew angle is a very small value of about 3 μm. This requires not only high processing accuracy but also sufficient flying height stability. Was difficult.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and allows a magnetic head to fly quickly when a magnetic disk rotates, to improve the flying stability of the magnetic head, and to reduce the flying height and the sticking phenomenon of the magnetic head. It is an object of the present invention to provide a magnetic disk and a magnetic head which both achieve the prevention of the above, and in particular improve the durability against CSS.

[0020]

According to a first aspect of the present invention, there is provided a magnetic disk in which information is read and written by a magnetic head, and the magnetic head is rotated when the rotation of the magnetic disk is stopped. A plurality of protrusions are formed on the magnetic disk surface in contact with each other, and a protrusion having an average diameter of 10 to 500 nm is formed at the top of the protrusions.
001 to 1 / nm ² .

According to a second aspect of the present invention, there is provided a magnetic disk on which information is read and written by a magnetic head, wherein a plurality of protrusions are provided on a surface of the magnetic disk which is in contact with the magnetic head when the rotation of the magnetic disk is stopped. Formed, with an average diameter of 10-500 nm on top of the protrusions
Are formed at 0.001 to 1 / nm ² , and fine grooves along the circumferential direction are formed in the magnetic recording portion of the magnetic disk surface. .

According to the third aspect of the present invention, there is provided a magnetic disk according to the first aspect.
Alternatively, the height of the protrusion formed on the magnetic disk according to 2 is 5 nm or more.

The magnetic disk according to the fourth aspect is the second aspect of the present invention.
Wherein the average pitch of the fine grooves formed along the circumferential direction is 2 μm or less.

According to a fifth aspect of the present invention, there is provided a magnetic disk according to the second aspect.
Alternatively, in the magnetic disk described in 4, the difference between the average height and the maximum height of the surface on which the fine grooves are formed along the circumferential direction is 40 nm or less.

According to a sixth aspect of the present invention, there is provided a magnetic disk in which information is read and written by a magnetic head and which is rotationally driven, wherein at least one of a front surface and a rear surface of the magnetic disk has air facing forward in the rotation direction of the magnetic disk. A plurality of protrusions having a compression portion are formed, and a protrusion having an average diameter of 10 to 500 nm is 0.001 on the top of the protrusion.
-1 / nm ² .

According to a seventh aspect of the present invention, there is provided a magnetic disk, wherein the magnetic head floats and travels when rotating and the magnetic head comes into contact when the rotation is stopped. A plurality of protrusions formed by connecting the guide portions in a crotch-opening manner in an inclined state are formed with the open side of each protrusion facing forward in the rotation direction of the magnetic disk. 10 diameter
It is characterized in that 0.001 to 1 protrusions / nm ^{2 are} formed.

According to an eighth aspect of the present invention, the protrusions formed on the inner peripheral side of the magnetic disk are formed smaller than the protrusions formed on the outer peripheral side of the magnetic disk and are densely arranged. A magnetic disk according to claim 6 or 7, wherein:

[0028]

According to a ninth aspect of the present invention, there is provided a magnetic head which levitates and runs on a magnetic disk in a rotationally driven state and contacts a magnetic disk in a stopped state. A protrusion having an air compression section facing the rear side in the rotation direction of the disk is formed,
On the top of the protrusion, 0.001 to 1 protrusions / nm ² having an average diameter of 10 to 500 nm are formed.

The magnetic head according to claim 1 0, wherein the floats running the magnetic disk of the rotary drive state, a magnetic head which contacts the magnetic disk in a stopped state, another air guide part of two or more One or more protrusions connected in the form of a crotch open in an inclined state, each protrusion is formed with its open side facing the rear side in the rotation direction of the magnetic disk, and the average diameter is formed on the top of the protrusion. The projections of 10 to 500 nm are 0.0
It is characterized in that it is formed in an amount of from 01 to 1 / nm ² .

[0031]

According to the magnetic disk of the present invention, when the magnetic disk contacts the magnetic disk when the rotation of the magnetic disk is stopped, the magnetic head has a plurality of convex portions formed on the magnetic disk or convex portions formed on the top portions. It comes into contact with the magnetic disk through the projected protrusion. That is, the state of contact between the magnetic disk and the magnetic head is no longer the state of contact between the conventional mirror surfaces, so that the phenomenon that the magnetic head is attracted to the magnetic disk does not occur. Therefore, the failure of the magnetic recording device which has conventionally occurred due to the magnetic head adsorption phenomenon does not occur.

In particular, by setting the size and the number of protrusions within a specific range, the durability performance against CSS operation can be improved. In addition, by setting the size of the protrusion within a specific range, the flying stability of the magnetic head can be further improved. That is, the height of the protrusion is 5
When the thickness is not less than nm, the adsorption phenomenon between the magnetic disk surface and the magnetic head can be reliably avoided, and good flying stability of the magnetic head can be maintained. The height of the protrusion is 80
When the thickness is not more than nm, it is possible to secure a low flying height of the magnetic head, achieve a high recording density, and keep the flying stability.

In the portion for performing recording and reproduction of the magnetic disk,
By forming a plurality of fine grooves along the circumferential direction, and by setting the pitch of each groove to 2 μm or less, the phenomenon of sticking to the magnetic head is prevented, and the magnetic anisotropy of the magnetic disk is improved. The magnetic force can be increased.

When a plurality of fine grooves are formed along the circumferential direction, the maximum height Rp from the center of roughness is 40
When the thickness is equal to or less than nm, the stability of the magnetic head at low flying height is maintained.

In a magnetic disk having a plurality of protrusions provided with air compression portions facing the front side in the rotation direction of the magnetic disk formed on the surface, the air compression portions of each protrusion act when the magnetic disk rotates. A positive pressure region is generated on the surface of the magnetic disk, and an airflow is generated due to the region. Then, this air current acts on the magnetic head and causes the magnetic head to fly quickly. An airflow is generated by rotation even in a normal magnetic disk having no projection, but in a magnetic disk having a projection provided with an air compressing portion, a positive airflow generated by the air compression effect of the projection at the start of rotation. Since a strong air current can be immediately generated by the pressure, the magnetic head flies faster than before. Therefore, the time when the magnetic head contacts and rubs the magnetic disk at the start of rotation of the magnetic disk is shortened, and the possibility of damage to the magnetic disk is reduced.

If the magnetic disk provided with the air compression portion is smaller and densely arranged on the inner peripheral side of the magnetic disk than on the outer peripheral side of the magnetic disk, the peripheral speed is small. The difference in airflow generated between the inner peripheral side and the outer peripheral side where the peripheral speed is high can be reduced, and the flying height of the magnetic head can be made uniform between the inner peripheral side and the outer peripheral side. Therefore, the recording magnetic field of the magnetic head and the leakage magnetic field of the magnetic disk can be kept constant.

In the magnetic head of the present invention, when the magnetic head is in contact with the magnetic disk when the rotation of the magnetic disk is stopped, the magnetic head is formed on a plurality of convex portions or convex portions formed on the magnetic disk. Is in contact with the magnetic disk through the protrusions formed. That is, the state of contact between the magnetic head and the magnetic disk is no longer the state of contact between the conventional mirror surfaces, so that the phenomenon that the magnetic head is attracted to the magnetic disk does not occur. Therefore, the failure of the magnetic recording device which has conventionally occurred due to the magnetic head adsorption phenomenon does not occur. In particular, by setting the size and the number of the convex portions within a specific range, the durability performance against the CSS operation can be improved.

In the case of a magnetic head in which a protrusion having an air compressing portion facing rearward in the rotation direction of the magnetic disk is formed on the bottom surface of the magnetic head on the side of the magnetic disk, the protrusion may be formed when the magnetic disk rotates. A positive pressure generated by the action of the air compression section is generated on the bottom side of the magnetic head. Therefore,
This positive pressure causes the magnetic head to fly more quickly than the conventional magnetic head. Therefore, when the magnetic disk starts rotating,
The time during which the magnetic head contacts and rubs the magnetic disk is reduced, and the possibility of damage to the magnetic disk is reduced.

[0039]

Embodiments of the present invention will be described below with reference to the drawings. [Magnetic Disk] FIGS. 1 to 4 show an embodiment of a magnetic disk employing the structure of the present invention. The magnetic disk 10 of this example is configured by coating a magnetic layer, a protective film, or a plurality of intermediate films as necessary on the surface or both surfaces of a disk-shaped substrate made of metal, glass or resin. And used as a magnetic recording medium such as a magnetic recording device of a computer.

The magnetic head 1 is pressed by a spring plate 3 against the front side or both sides of the magnetic disk 10 with a predetermined spring pressure. The magnetic head 1 is connected to a drive device (not shown) that supports the spring plate 3, and the magnetic head 1 is rotated or translated to a desired position on the inner peripheral side of the magnetic disk 10. To a desired position on the outer peripheral side. As shown in FIG. 2, the magnetic head 1 of this embodiment is wound around a plate-like slider 2a, and a core 2b and a core 2b formed at the rear end (trailing side) of the slider 2a. The slider 2a is provided with an inclined surface 2d for floating on the bottom surface on the leading end side (leading side) of the slider 2a.

As shown in FIGS. 3 and 4, at least one of the front surface and the back surface of the magnetic disk 10 has a protrusion 11 on the inner peripheral portion with which the magnetic head comes into contact when the rotation of the magnetic disk is stopped.
A plurality of textures 12, which are fine grooves formed along the circumferential direction, are formed on the outer peripheral portion where the magnetic recording is performed. The protrusion 11 protrudes from the surface of the magnetic disk 10 and has a cylindrical shape as shown in FIG. 5, a hexagonal prism as shown in FIG. 6, or a cone as shown in FIG. Various things such as a trapezoidal one and a V-shaped one as shown in FIG. 8 can be adopted. Each of the protrusions 11 has a height d of 5 nm or more, and more preferably 5 nm or more.
nm or less.

Further, a plurality of projections 42 are further formed on the top of each projection 11. The shape of the convex portion 42 may be any shape such as a conical shape, a cylindrical shape, or a triangular pyramid shape, but the average diameter parallel to the plane of the magnetic disk may be in the range of 10 to 500 nm. preferable. Further, the protrusions 42 are formed in a range of 0.001 to 1 per unit area (nm ² ).
It is preferable that there are a plurality of such groups. If the number is smaller or larger than this number, the durability to CSS decreases.

The texture 12, which is a fine groove along the circumferential direction formed on the outer peripheral portion of the magnetic disk 10 on which magnetic recording is performed, has an average pitch, which is the interval between the grooves 12, 12,. It is preferably 2 μm or less. Further, the roughness of the outer surface of the magnetic disk due to the fine grooves 12 is determined by the difference between the roughness center and the maximum height, that is, the average depth (M− M line)
It is desirable that the difference Rp between the highest position (H line) is 40 nm or less.

In the structure of this embodiment, the bottom surface of the magnetic head 1 comes into contact with the surface of the magnetic disk 10 on which the projection 11 having the convex portion 42 on the top is formed. Since the contact state of 10 is not a contact between mirror surfaces, the adsorption phenomenon does not occur.

The total area of the tops of the projections 11 is preferably 15% or less of the total area of the region where the projections 11 are formed. In the region where the texture 12 is formed, the depth of the groove is preferably 5 nm or more, and the total area of the upper surface of the region where the texture 12 is formed is more than the total area of the region. 15%
The following is preferred. Furthermore, the sum of the area of the top of the protrusion 11 and the area of the upper surface of the texture 12 is
It is preferable that the amount is within 15% with respect to the total sum of these formed regions.

The magnetic disk 1 having the above configuration
0 will be described with reference to FIGS. To manufacture the magnetic disk 10 of the present embodiment,
A disk-shaped substrate 13 made of Al, Al alloy, glass, or the like is prepared. After chamfering or surface processing is performed on the substrate 13, a coating film 14 such as Ni-P is formed on the surface by plating or other means. It is formed as shown in FIG.

Next, the surface of the coating film 14 is polished. The projections 11A, 11A, 11A,...
4 is formed on the inner peripheral side. Projections 11A, 11A, 11
For forming A,..., A photolithography technique including the steps shown in FIG. 11 can be used.

The method of forming the projection 11A by the photolithography technique shown in FIG. 11 will be described in detail below. First, a photoresist 16 is applied to the coating film 14 shown in FIG. 11A at least on the inner peripheral side of the upper surface of the coating film 14 as shown in FIG. As shown in FIG. 11C, a photomask 17 having a shape in which a number of protrusions 11A described in FIG. Then, the resultant is exposed to light including ultraviolet rays and then developed to form a photoresist 16 having a fine pattern of a desired shape as shown in FIG.

After this is further etched as shown in FIG. 11E, the magnetic disk substrate 15 is formed by subjecting the photoresist portion to peeling as shown in FIG. 11F. In describing the method of forming the projection 11A, the photoresist 1 shown in FIG.
Although 6 is an example of a negative type, the protrusion 11A may be formed of a positive type photoresist. At this time, the photomask 17 placed on the upper surface of the photoresist 16 is opposite to the negative type in that the photomask 1 is formed only on the shape of the protrusion 11A.
7 is left.

Then, as shown in FIG. 10C, the outer peripheral portion of the magnetic disk substrate 15 formed as described above is
Processing for forming the texture 12A is performed. The processing for forming the texture 12A can be performed by pressing the polishing tape, in which the abrasive grains are specially adjusted, only to the outer peripheral portion of the magnetic disk substrate 15 rotating at a constant angular velocity with an appropriate pressure. Further, the texture 12A can be formed by the photolithography technique as described above. It is preferable to form by photolithography because the size, shape, formation density and the like can be adjusted. Note that this texture processing may be performed before the formation of the protrusion 11A by the above-described photolithography technique.

Next, FIG.
The underlayer 18 made of Cr or the like as shown in FIG. Then, Co-Ni, Co-N
A magnetic layer 19 made of i-Cr, Co-Cr-Ta or the like is coated by means such as sputtering as shown in FIG. Further, a protective film 20 made of carbon or the like is coated by means such as sputtering as shown in FIG. 10F, and a fluorine-based lubricating film 21 is formed by dip coating or the like to complete the magnetic disk 10.

In the above manufacturing method, the protrusions 11A, 11A, 11A are polished after the polishing shown in FIG.
... and the texture 12A are formed, so that each film formed thereon sequentially has the protrusions 11A, 11A,
.. And the texture 12A, the protrusions 11, 11, 11... Having the convex portions 42 on the top are formed on the inner peripheral side of the surface of the magnetic disk 10 on the outer peripheral side. Are textures 12, 12, 12 of fine grooves in the circumferential direction having a shape along each ring of the texture 12A.
.. Are formed.

In the above-described manufacturing method, the projections 11A are formed in the course of laminating a large number of films. However, the step of forming the projections 11A is performed, for example, after the formation of the protective film 20, and the upper surface of the protective film 20 is formed. The protrusion 11A may be formed only on the peripheral side. In this case, the protrusion 11A is formed on the protective film 20.
Alternatively, a large number of protrusions 11A may be transferred at a time by pressing a stamper formed with a large number of molds.

When the protective film 20 is a hard film,
The step of forming a new intermediate film is incorporated before the step of forming the protective film 20, and a large number of protrusions 11A are formed on the intermediate film by using a stamper, and the protective film 20 is put on the protrusions 11A. Many 11A can be formed at once. The projections 42 are also formed on the tops of the projections 11 by performing the above-described manufacturing method. However, the size and the number of the projections 42 can be adjusted by performing reverse sputtering. In FIG. 10, the coating film and the protrusions are shown only on one side of the magnetic disk, but they may be formed on both sides as needed.

As another embodiment of the present invention, FIG.
There are magnetic disks 90 shown in FIGS. The magnetic disk 90 of this example is also similar to the magnetic disk shown in FIGS.
On at least one of the front surface and the back surface, a plurality of protrusions 91 formed by the concave space 43 provided on the surface of the magnetic disk 90 are provided on the inner periphery thereof, and are formed along the circumferential direction on the outer periphery. A texture 92 which is a fine groove formed is provided. That is, the protrusion 91 in this example is formed by the concave space 43 provided on the surface of the magnetic disk 90 and does not protrude above the surface of the magnetic disk 90.

The shape of the projection 91 is cylindrical as shown in FIG. 5, hexagonal column as shown in FIG. 6, truncated cone as shown in FIG. 7, or shown in FIG. The magnetic disk 10 shown in FIGS.
Various types of protrusions can be employed in the same manner as the protrusions formed on the substrate. Further, the height d ′ of each of the protrusions 91 is preferably 5 nm or more. More preferably, it is 5 nm or more and 80 nm or less.

At the top of each projection 91, a plurality of projections 42 are provided.
The shape of the convex portion 42 may be any shape such as a conical shape, a cylindrical shape, or a triangular pyramid shape, but its average diameter parallel to the plane of the magnetic disk is 10 to 10.
It is preferably within the range of 500 nm. In addition, the convex portion 4
It is preferable that 0.002 to 1 of 2 exist per unit area (nm ² ). If the number is smaller or larger than this number, the durability to CSS decreases.

It is preferable that the texture 92 formed on the outer periphery of the magnetic disk substrate along the circumferential direction has a pitch between the rings of 2 μm or less. Further, the maximum height Rp from the roughness center of the outer peripheral portion of the magnetic disk surface due to the texture 92 is preferably 40 nm or less.

Also in this magnetic disk 90, FIGS.
Similarly to the magnetic disk 10 shown in FIG. 4, it can be manufactured by the manufacturing method described with reference to FIGS. That is,
Unlike the magnetic disk 10 shown in FIGS.
The photolithography technique may be applied so as to form the recessed space 43 for forming 1.

Magnetic disk 10 or magnetic disk 90
If the shapes of the protrusions 11 and 91 formed above are V-shaped as shown in FIG. 8, special effects as described below can be obtained. The V-shaped projection 5 shown in FIG.
The air guide portions 5a,
A plane triangular space region formed by being sandwiched between the air compression portions 5a is referred to as an air compression portion 5b.

Magnetic disk 10 provided with V-shaped projection 5
When the magnetic disk 10 starts rotating, V
Air enters the compressed air portion 5b of the character-shaped projection 5. The air that has entered the air compressor 5b of the V-shaped protrusion 5 is compressed from both sides by the air guides 5a, 5a. Area occurs.

The large number of V-shaped protrusions 5 formed on the front surface or the back surface of the magnetic disk 10 rotate while forming a positive pressure region above each of them, so that a large air flow is generated and pressed against the magnetic disk 10. The magnetic head 1 is easily levitated by the lift generated by the airflow, and levitates with respect to the magnetic disk 10.

Each of the projections 22 and 2 having a shape as shown in FIGS.
In the magnetic disk 10 on which the V-shaped protrusions 5 are formed, the airflow is generated by the rotation in the magnetic disk 10 on which the protrusions 3 and 24 are formed, and also on the conventional magnetic disk on which such protrusions are not formed. In this case, a strong air flow can be immediately generated by the positive pressure generated by the air compression effect of the V-shaped projection 5 at the start of rotation, so that it is possible to generate a strong air flow immediately, as shown in FIGS. The magnetic head 1 can fly and travel faster than a magnetic disk provided with shaped protrusions 22, 23, and 24. Therefore, in the magnetic disk 10 on which the V-shaped protrusions 5 are formed, the magnetic head 1 is
The time during which the magnetic disk 10 and the magnetic head 1 are brought into contact with and rubbed against the surface of the magnetic disk 10 is shortened.

The following is a modification of the projection which can obtain substantially the same effect as that of the V-shaped projection 5 shown in FIG. 8 as described above.

FIG. 15 shows another example of the configuration of the V-shaped projection 5. In this example, the air guide portion 25 a of the V-shaped projection 25 formed on the magnetic disk 10 includes the magnetic disk 10. The front side 25α in the rotation direction is formed thicker than that of the projection 5 shown in FIG.
5β is formed thinner than the front side 25α. Other configurations are the same as those of the V-shaped projection 5 shown in FIG.

By adopting the configuration shown in FIG. 15, the volume of the air compression portion 25b can be increased, and the amount of air compressed by the air guide portions 25a of the V-shaped projection 25 can be increased. it can. Therefore, a higher positive pressure can be generated than that of the V-shaped protrusion 5 having a uniform thickness of the air guide portion 25a shown in FIG. 8, and the magnetic head 1 can fly faster.

The V-shaped projection 26 having the shape shown in FIG.
The magnetic disk 1 on which the V-shaped protrusion 26 of this example is formed
0, the compression auxiliary groove 9 which is a groove for air compression auxiliary is formed on the surface portion of the magnetic disk 10 below the air compression portion 26b of the V-shaped projection 26. The depth of the compression auxiliary groove 9 is such that the V-shaped projection 26
The magnetic disk 10 is formed so as to be deep below the front side 26α in the rotation direction and to be shallow below the rear side 26β in the rotation direction of the magnetic disk 10.

By adopting the configuration shown in FIG. 16, the volume of the air compressor 26b is increased, and the air guides 26a,
Since the amount of air compressed by 6a can be increased, a high positive pressure can be generated, and the magnetic head can fly quickly.

The example of the projection having the shape shown in FIG. 17 is a further modified example of the V-shaped projection shown in FIGS. 8, 15 and 16, and this projection 27 has the air guide portions 27a and 27a as walls. It is formed in a U-shape by connecting with the air guiding portion 27A.
A region surrounded by the walls 27a and 27a and the wall 27A is an air compressor 27b. With the U-shaped projection 27 having this configuration, substantially the same effects as those of the V-shaped projections 5, 25, and 26 described above can be obtained.

The projection 28 having the shape shown in FIG. 18 is formed by connecting the air guides 28a, 28a in an X-shape. The end of one air guide 28a and the other air guide 28a are formed.
An air compression portion 28b is formed between the air compression portion 28b and the end portion. With the X-shaped projection 28 having this configuration, the V
Almost the same effects as those of the U-shaped protrusions 5, 25, 26 and the U-shaped protrusion 27 can be obtained.

The protrusion 29 having the shape shown in FIG. 19 has short air guide portions 29a, 29a at both ends of the horizontally long wall portion 29A.
At right angles. With the projection 29 having this configuration, the V-shaped projections 5, 25, 26,
Almost the same effects as those of the U-shaped projection 27 and the X-shaped projection 28 can be obtained.

FIG. 20 shows another example of the configuration of the projection according to the present invention. The projection 35 in this example is a combination of a pair of V-shaped half patterns 35A, 35A. In this example, since the half turns 35A, 35A are provided symmetrically along the rotation direction of the magnetic disk 10, the positive pressure region generated by the air compression unit 35b of one half pattern 35A and the other half pattern are formed. The positive pressure area combined with the positive pressure area generated by the air compression section 35b of 35A has an effect of causing the magnetic head 1 to fly. As in this example, a configuration may be used in which the composite positive pressure region is generated by the protrusion 35 composed of two half patterns to generate an airflow for causing the magnetic head 1 to float.

FIG. 21 shows an example of the configuration of a projection according to the present invention. In this example, the projection 36 has two elongated plate-like air guide portions 36a, 36a opposed to each other in a C-shape. Configuration. When this configuration is employed, the air guide 36
a, there is a concern that air will escape from the gap D between the gaps 36a and 36a.
m or less. With this configuration, air leakage from the gap D can be prevented,
A positive pressure can be generated in substantially the same manner as the projection 5 shown in FIG.

In this example, if the magnitude of the positive pressure to be generated can be slightly reduced, the width of the gap D between the air guides 36a is slightly longer than the length of the free stroke of air. The air compression portion 36b may be formed so that even if air is released from the gap D, a larger air compression effect is generated in the air compression portion 36b.

FIG. 22 shows a case where the V-shaped projections 5 having the structure shown in FIG. 8 are formed on the magnetic disk 10 and the size of the V-shaped projections is changed in the radial direction of the magnetic disk 10 for each row. An example is shown. In this example, a V-shaped projection 5 having the same size as the example shown in FIG. 8 and a V-shaped projection 5 ′ having a slightly smaller and thinner shape are sequentially arranged in the radial direction of the magnetic disk 10. It was done. In FIG. 22,
The state in which the magnetic head 1 is in contact with the V-shaped protrusions 5, 5 is indicated by a two-dot chain line.

FIG. 23 shows an example of the configuration of a projection according to the present invention. In this example, the projection 37 is composed of bent air guide portions 37a, 37a and a tapered wall portion connecting these. 37c, and the air compression unit 37b
Are formed. With the projection 37 having this configuration, substantially the same effect as the V-shaped projection 5 described above can be obtained.

FIG. 24 shows an example of the configuration of a projection according to the present invention. In this example, the projection 38 has a shape in which air guide portions 38a, 38a that are slightly curved are connected. With the projection 38 having this configuration, substantially the same effect as the V-shaped projection 5 described above can be obtained.

FIG. 25 shows an example of the configuration of a projection according to the present invention. In this example, the projection 39 has a shape in which three linear air guides 39a, 39a, 39a are connected. . With the projection 39 having this configuration, the same effect as the V-shaped projection 5 described above can be obtained.

As described above, various shapes can be considered for the shape of the protrusion, and the shape of the protrusion may be different from the bottom surface (the medium facing surface) of the magnetic head mirror-finished during the CSS operation and the surface of the magnetic disk. Of course, as long as the object is not to cause the adsorption phenomenon, the invention is not limited to the above-described one.

Next, the relationship between the arrangement state and the size when the V-shaped protrusions and various deformed protrusions derived from the V-shaped protrusions are formed on a magnetic disk will be described. V-shaped protrusions formed on the magnetic disk (in the following description, protrusions 25, 26, 27, 28, 29, 35, 36, 37, 3 of various shapes deformed from the V-shaped protrusions)
The arrangement state of the V-shaped projections 8 and 39 is not limited to the arrangement configuration in which the V-shaped projections are formed concentrically on the inner peripheral side of the magnetic disk 10 in contact with the magnetic head.
As shown in FIG. 26, the V-shaped protrusions 30 to 34 are sequentially increased in size from the inner peripheral side to the outer peripheral side along the rotation direction of the magnetic disk 10. Is an example of the array configuration. In the case of a V-shaped projection, it can be formed on the entire surface of the magnetic disk including the outer periphery as well as the inner periphery of the magnetic disk.

FIG. 27 shows another example of the arrangement of the V-shaped projections 30 to 34. In this example, the projections 30, 31, 32, 3
3, 34 are sequentially arranged, and each V-shaped projection 30 to
34 are arranged in a zigzag pattern in the circumferential direction of the magnetic disk 10. That is, although various arrangement methods are conceivable for the arrangement of the V-shaped projections 30 to 34, any arrangement method may be applied.

Next, the size of the V-shaped projection 40 will be described with reference to FIG. The V-shaped projection 40 includes air guide portions 40a, 40a. In this V-shaped projection 40, the length of the air guide 40a is assumed to be A, the height of the air guide 40a is assumed to be B, and the width of the tip of the air guide 40a is assumed to be C. It is assumed that the width of the tip of the portion where the air guides 40a abut each other is D (in this V-shaped projection 40, the width of the tip of the air guide 40a is also D). The radial area of the magnetic disk 4 shown in FIG.
Is divided into zones, zones and zones. Here, it is assumed that the width D of the V-shaped protrusion in all zones is 5 μm. It is also assumed that the pitch between the protrusions is 0.1 mm in all zones. Further, let the air compression ratio be K.

Under the above conditions, for example, in the zone, A = 0.32 to 0.46 mm, C = 0.07
mm, K = 15-22%, A = 0.46 in the zone
~ 0.60 mm, C = 0.07 mm, K = 12-15%,
In the zone, A = 0.60-0.74 mm, C = 0.0
7 mm, K = 9-12%. At this time,
The inner peripheral portion of the magnetic disk has a large K with respect to the outer peripheral portion, and since the length of A is short, the magnetic disk opposes a large number of magnetic heads. The height B is at least 5 nm, more preferably at least 5 nm and at most 80 nm, even more preferably at least 60 nm and at most 80 nm.
It is preferably not more than nm. If it is less than 60 nm, the air compression effect is reduced, and if it is less than 5 nm, an adsorption phenomenon occurs with the magnetic head.

FIGS. 31 and 32 show the relationship between the arrangement and size of the inner and outer peripheral portions of a V-shaped projection formed on one magnetic disk. FIG. 31 shows a protrusion 45 on the inner peripheral side of the magnetic disk, and FIG. 32 shows a protrusion 46 on the outer peripheral side of the magnetic disk. As in this example, the size of the protrusions 45 on the inner peripheral side and the size of the protrusions 46 on the outer peripheral side can be changed in the arranged state. FIGS. 31 and 32 show the length of the slider of the magnetic head (the length from the leading end to the trailing end) and the width of the rail of the slider. The length of the slider and the width of the rail portion shown in FIGS. 31 and 32 are appropriately changed according to the shape and size of the magnetic head.

The configuration of this example addresses the phenomenon that the rotational speed of the magnetic disk is constant, the peripheral speed differs between the inner peripheral side and the outer peripheral side, thereby causing the flying height of the magnetic head to differ. It is a configuration for. That is, in a normal magnetic disk having no protrusions, the airflow generated at the outer peripheral portion having a high peripheral velocity is strong, so that the flying height of the magnetic head is large, and the airflow generated at the inner peripheral portion having a low peripheral speed is small, so that the magnetic flow is small. The flying height of the head is reduced. On the other hand, in the configuration shown in FIGS. 31 and 32, the V-shaped projections 45 are small and densely arranged so that a stronger airflow can be generated in the inner peripheral portion having a low peripheral speed, and In the portion, the V-shaped projections 46 are enlarged and sparsely arranged.

By adopting such a configuration, in the magnetic disk, the difference between the airflows generated on the inner peripheral side having a lower peripheral speed and the outer peripheral side having a higher peripheral speed is reduced, and the flying height of the magnetic head is reduced on the inner peripheral side. And the outer periphery can be made uniform.

[Test 1] In the magnetic disk 10 shown in FIGS. 1 to 4, the following test was performed in order to define the upper limit of the height d of the protrusion 11. Magnetic disk substrate 1
The projections 1 having different heights are formed by photolithography on the inner peripheral portion having a radius of 25 mm or less from the center of 0.
1 were prepared. A magnetic head equipped with an AE sensor that generates a signal when touched,
These were floated on the magnetic disk. When the flying height of the magnetic head is gradually reduced, the flying height when the magnetic head comes into contact with the magnetic disk to generate an AE signal is defined as the flying limit. The height relationship was investigated. FIG. 33 shows the measurement results.

As a result of the test described above, when the height d of the protrusion 11 was 100 nm or more, a slight fluctuation was observed in the flying posture of the magnetic head. In addition, as shown in FIG. 33, when the height d of the projection 11 is 80 nm or less, the floating limit is at a position 30 to 40 nm higher than the height of the projection. That is, the height d of the projection 11 is 8
It can be seen that if it is lower than 0 nm, it is possible to stably cope with low flying of 30 to 40 nm.

Subsequently, in order to define the lower limit of the height d of the protrusion 11 provided on the magnetic disk 10, the same test sample as that used in the above test was used. The relationship between the height d of the projection 11 and the suction force when the lubricant was applied to the surface of the projection 11 was examined. FIG. 34 shows the measurement results. From FIG. 34, it can be seen that when the height d of the protrusion 11 is less than 5 nm, a large suction force is generated. Therefore, from Test 1 described above, the height d of the protrusion 11 provided on the magnetic disk 10 is suitably from 5 nm to 80 nm, and if it is less than 5 nm, the adsorption phenomenon between the magnetic head and the surface of the magnetic disk 10 cannot be prevented. 8
At 0 nm or more, the flying stability of the magnetic head cannot be maintained, and it is understood that it is difficult to cope with the low flying of the magnetic head.

[Test 2] In the magnetic disk 10 shown in FIGS. 1 to 4, the relationship between the pitch of the texture 12 and the coercive force was examined. In the test, each magnetic disk 10 having a texture 12 processed at a different pitch was formed on an outer peripheral portion of a region having a radius of 25 mm or more from the center of the magnetic disk 10 described above.
Were prepared, and the coercive force of the magnetic disks was measured. FIG. 35 shows the measurement results. The pitch at this time is 100
It was obtained as a visual field average by SEM observation at a magnification of 00.

From FIG. 35, the pitch of the texture 12 and the coercive force are inversely proportional, and the pitch of the texture 12 is 2 μm.
At m or more, it is apparent that there is almost no difference in coercive force from the case where the texture 12 is not provided. Therefore, in increasing the coercive force, it is understood that providing the texture 12 with a pitch of 2 μm or more loses the meaning of providing the texture.

[Test 3] In the magnetic disk 10 shown in FIGS. 1 to 4, the relationship between the roughness of the texture 12 formed on the magnetic disk 10 and the flying stability of the magnetic head was examined. The test was performed with a radius of 25m from the center of the magnetic disk 10.
The magnetic head with the AE sensor attached is prepared by preparing each magnetic disk in which the outer periphery of the area of m or more is machined with different roughness.
It was floated on the magnetic disk. When the flying height of the magnetic head is gradually reduced, the flying height of the magnetic head when the magnetic head comes into contact with the magnetic disk and an AE signal is generated is defined as the flying limit. Maximum height R from the center of roughness of the outer peripheral surface of the disc
The relationship of p was measured. FIG. 36 shows the measurement results.

As shown in FIG. 36, if the maximum height Rp of the surface of the magnetic disk from the roughness center is 40 nm or less due to the texture 12 formed on the outer periphery of the magnetic disk, the low flying height is 100 nm or less. It can be understood that the magnetic head can be reduced in flying height.

As described above, the tests 1 to 3 show that the magnetic disk 10
In the above, the height d of the protrusion 11 provided on the magnetic disk 10 is suitably from 5 nm to 80 nm. Further, in the texture 12 provided on the outer peripheral portion of the magnetic disk 10, when the pitch between the rings is 2 μm or less, the coercive force increases in inverse proportion to the pitch, and the required coercivity for the magnetic disk 10. Magnetic force can be obtained. Further, by setting the maximum height Rp from the roughness center of the outer peripheral portion of the surface of the magnetic disk 10 by the texture groove 12 formed on the outer peripheral portion of the magnetic disk to 40 nm or less, it is possible to cope with a low flying height of the magnetic head. It is.

[Test 4] The magnetic disk 1 shown in FIGS.
At 0, a CSS durability test was performed. A Cr layer (100 nm), a magnetic layer (60 nm), and a carbon film (30 nm) are sequentially formed on a substrate by using a sputtering apparatus (mdp: manufactured by Intevac, USA). A projection having a convex portion at the top was formed by the method. The convex part is
Samples 1 to 8 having the respective densities and sizes shown in Table 1 below were used. An atomic force microscope was used to measure the number and size of the convex portions. The CSS operation was repeatedly performed on each of the magnetic disks of Samples 1 to 8, and the durability was tested.

[0096]

[Table 1]

In all of the magnetic disks of Samples 1 to 8, even if the CSS operation was performed 30000 times, the magnetic disk and the magnetic head used in the test were not affected at all, and the magnetic disks of Samples 1 to 5 were not affected. , CS
Even after performing the S operation 100000 times, no trouble occurred in the magnetic disk and the magnetic head used for the test, and the CSS operation could be sufficiently used even after the 100000 times of the CSS operation.

Therefore, if the magnetic disk has protrusions having a diameter of 32 to 374 nm in a size of 0.0035 to 0.076 / nm ² , it can withstand at least 30,000 CSS operations and a diameter of 32 to 352 nm. The size of the projection is 0.056
It can be seen that a magnetic disk formed with .about.0.076 / nm ² is a magnetic disk with extremely high durability that can withstand at least 100,000 times of CSS.

Further, the same test was performed to measure the number of durable CSS times of the magnetic disk with respect to the density of the protrusions. FIG. 37 shows the test results. From FIG. 37, it is found that the density of the protrusions is about 0.001 / nm ² or more and 1 / nm ²
If it is below, it is a long-awaited standard of durability performance 3
It turns out that CSS of 0000 times is satisfied.

[Magnetic Head] FIGS. 38 and 39 to 41
Shows an embodiment in which the present invention is applied to a monolithic three-rail type magnetic head. The magnetic heads 48 and 50 of this example are configured by joining a core 53 to the center of the rear end of a slider 52 having three rails 51. At the tip of each rail 51, an inclined surface 55 is formed for assisting floating travel. The magnetic heads 48, 5 of this example
0, the right end in FIGS. 38 and 39 is the leading side, that is, the rear side in the rotation direction of the magnetic disk.
The left rear ends of the tracks 8 and 39 are on the trailing side, that is, the front side in the rotation direction of the magnetic disk.

In the magnetic head 48 shown in FIG.
A plurality of convex portions 49 are formed on the rail portion 51. Various shapes such as a conical shape, a cylindrical shape, and a triangular pyramid shape can be applied to the convex portion 49. The size of the convex portion 49 is within an average diameter of 10 to 500 nm parallel to the surface of the rail portion 51. Preferably, there is. Further, the protrusion 49 has a unit area (n
0.001 to 1 per m ² ) is preferred. If the number is smaller or larger than this number, the durability to CSS decreases.

In the magnetic head 50 shown in FIG.
A V-shaped protrusion 56 is formed on the rail portion 51.
The protrusion 56 connects two air guides 56a, and directs an air compressor 56b formed between them to the rear side in the rotation direction of the magnetic disk.

Further, a plurality of projections 49 (see FIG. 41) are formed on the top of the V-shaped projection 56. Various shapes such as a conical shape, a cylindrical shape, and a triangular pyramid shape can be applied to the convex portion 49. The size of the convex portion 49 is within an average diameter of 10 to 500 nm parallel to the surface of the rail portion 51. Preferably, there is. Further, it is preferable that 0.001 to 1 protrusions 49 exist per unit area (nm ² ). If less or more than this number, CS
This is because the durability to S decreases.

The magnetic heads 48 and 50 may be used in the same manner as in a conventional magnetic disk having no projections, or may be formed with the projections or projections of the present invention described above. Used for the magnetic disk 10. Even if used for any of the above magnetic disks,
Since the rails 51 are formed with the protrusions 49 or the protrusions 56 having the protrusions 49, even if the magnetic heads 48 and 50 come into contact with the magnetic disk when the rotation of the magnetic disk is stopped, the mirror surface of the magnetic disk and the magnetic surface are not affected. Unlike the case of contact with the mirror surface of the head, the adsorption phenomenon between mirror surfaces does not occur,
The problem that the magnetic heads 48 and 50 do not run due to the adsorption phenomenon does not occur. Further, the V-shaped projection 5
In the case of the magnetic head 50 formed with the magnetic disk 6, the airflow generated by the rotation of the magnetic disk can be compressed by the air compressing portion 56b of the V-shaped projection 56 and converted into lift. In this way, the magnetic head 50 can fly faster, thereby stabilizing the flying movement of the magnetic head 50 and reducing the risk of surface breakdown of the magnetic disk.

FIG. 42 shows an embodiment in which the present invention is applied to a composite type two-rail type magnetic head. In the magnetic head 60 of this example, the rail portion 6 of the slider 61
This is an example in which a plurality of V-shaped projections 63 are formed in a staggered pattern on 2, 62. In the drawing, reference numeral 64 denotes a core portion. Also, in the magnetic head of this example, similarly to the magnetic heads shown in FIGS. 38 and 39 to 41, a plurality of convex portions (not shown) are formed on the tops of the protrusions 63.

FIG. 43 shows a case where the present invention is applied to a mini monolithic type 2.
An embodiment applied to a rail type magnetic head will be described. The magnetic head 70 of this example is an example in which a plurality of V-shaped protrusions 73 each having a convex portion (not shown) formed on a rail portion 72 of a slider 71 are formed linearly. In the drawing, reference numeral 74 denotes a core portion.

In the magnetic heads 50, 60, 70, the projections 56, 63,
Numeral 73 denotes the V-shaped projection 25 illustrated in FIG. 15, the V-shaped projection 26 illustrated in FIG. 16, and the V-shaped projection 26 illustrated in FIG. 16 in addition to the V-shaped projection illustrated in FIG. The illustrated U-shaped protrusion 27, the X-shaped protrusion 28 illustrated in FIG. 18, and FIG.
The protrusion 29 illustrated in FIG. 20, the protrusion 35 illustrated in FIG.
The protrusion 36 illustrated in FIG. 21, the protrusion 37 illustrated in FIG. 23, the protrusion 38 illustrated in FIG. 24, the protrusion 39 illustrated in FIG. 25, and the like can be applied.

In any of the types of magnetic heads described above, since the convex portion is formed on the medium facing surface of the magnetic head in contact with the magnetic disk, an attraction phenomenon does not occur between the magnetic head and the magnetic disk. In addition, it is possible to prevent poor starting. Further, in the case of a magnetic head having projections formed thereon, the airflow can be efficiently converted into lift by the projections, and the flying traveling of the magnetic head can be stabilized.

[0109]

According to the magnetic disk of the present invention, when the magnetic head is in contact with the magnetic disk when the rotation of the magnetic disk is stopped, the magnetic head contacts the plurality of protrusions or tops formed on the magnetic disk. It comes into contact with the magnetic disk via the projection on which the projection is formed. Therefore, since the conventional mirror-to-mirror contact does not occur, the phenomenon that the magnetic head is attracted to the magnetic disk does not occur. Therefore, even if the magnetic head flies at a low flying height, the failure of the magnetic recording apparatus that has conventionally occurred due to the adsorption phenomenon does not occur.

Further, by setting the size of the protrusion within a specific range, the flying stability of the magnetic head can be guaranteed. In particular, by setting the size and the number of the convex portions within a specific range, the durability performance against the CSS operation can be improved.

When the height of the projection is 5 nm or more, the phenomenon of attraction between the surface of the magnetic disk and the magnetic head can be reliably avoided, and when the height is 80 nm or less, good flying stability of the magnetic head can be obtained. Can be kept.

In the portion for performing recording and reproduction on the magnetic disk,
By forming a plurality of fine grooves along the circumferential direction, and by setting the pitch of each groove to 2 μm or less, the phenomenon of sticking to the magnetic head is prevented, and the magnetic anisotropy of the magnetic disk is improved. The magnetic force can be increased.

When a plurality of fine grooves are formed along the circumferential direction, the maximum height Rp from the center of roughness is 40
When the thickness is equal to or less than nm, the stability of the magnetic head at low flying height is maintained.

In a magnetic disk in which a plurality of protrusions having an air compression portion facing forward in the rotation direction of the magnetic disk are formed on the surface, the air compression portion of each protrusion acts when the magnetic disk rotates. A positive pressure region is generated on the surface of the magnetic disk, and an airflow is generated due to this. This airflow acts on the magnetic head and causes the magnetic head to fly quickly. Therefore, the time when the magnetic head contacts and rubs the magnetic disk at the start of rotation of the magnetic disk is shortened, and the possibility of damage to the magnetic disk is reduced.

If the protrusion provided with the air compression portion is formed on the inner peripheral side of the magnetic disk smaller than the outer peripheral side of the magnetic disk and is densely arranged, the peripheral speed is lower. The difference in airflow generated between the inner peripheral side and the outer peripheral side where the peripheral speed is high can be reduced, and the flying height of the magnetic head can be made uniform between the inner peripheral side and the outer peripheral side. Therefore, the recording magnetic field of the magnetic head and the leakage magnetic field of the magnetic disk can be kept constant.

In the magnetic head according to the present invention, when the magnetic disk is in contact with the magnetic disk when the rotation of the magnetic disk is stopped, the magnetic head is formed with a plurality of convex portions or convex portions formed on the magnetic disk. Is in contact with the magnetic disk through the protrusions formed. Therefore, since the conventional mirror-to-mirror contact does not occur, the phenomenon that the magnetic head is attracted to the magnetic disk does not occur. Therefore, the failure of the magnetic recording apparatus which has conventionally occurred due to the magnetic head adsorption phenomenon does not occur.

By setting the size of the protrusions in a specific range, the flying stability of the magnetic head can be guaranteed. In particular, by setting the size and the number of the convex portions within a specific range, the durability performance against the CSS operation can be improved.

[0118] In addition, the magnetic disk side of the rate of the magnetic head
If the magnetic head has a protrusion with an air compressing portion facing the rear side in the rotation direction of the magnetic disk on the bottom surface of the magnetic disk,
During rotation of the magnetic disk, a positive pressure generated by the air compression portion of the protrusion is generated on the bottom side of the magnetic head. Therefore, this positive pressure causes the magnetic head to fly faster than the conventional magnetic head. Therefore, the time when the magnetic head contacts and rubs the magnetic disk at the start of rotation of the magnetic disk is reduced, and the possibility of damage to the magnetic disk is reduced.

[Brief description of the drawings]

FIG. 1 is a plan view showing an embodiment of a magnetic disk according to the present invention and an arrangement state of a magnetic head.

FIG. 2 is a side view of an arrangement state of a magnetic disk and a magnetic head shown in FIG.

FIG. 3 is a side sectional view of the magnetic disk of the embodiment.

FIG. 4 is an enlarged view of a main part of FIG. 3;

FIG. 5 is a perspective view of an example of a protrusion.

FIG. 6 is a perspective view of an example of a protrusion.

FIG. 7 is a perspective view of an example of a protrusion.

FIG. 8 is a perspective view of an example of a protrusion.

FIG. 9 is a diagram for explaining the depth of a texture.

FIG. 10 is a process diagram for explaining the manufacturing process of the magnetic disk.

FIG. 11 is a process diagram for explaining a process of manufacturing a protrusion on a magnetic disk.

FIG. 12 is a plan view showing one embodiment of a magnetic disk.

13 is a side sectional view of the magnetic disk shown in FIG.

FIG. 14 is an enlarged view of a main part of FIG.

FIG. 15 is a side sectional view showing an example of a projection.

FIG. 16 is a side sectional view showing an example of a projection.

FIG. 17 is a perspective view of an example of a protrusion.

FIG. 18 is a perspective view of an example of a protrusion.

FIG. 19 is a perspective view of an example of a protrusion.

FIG. 20 is a configuration example of a projection.

FIG. 21 is a configuration example of a protrusion.

FIG. 22 is a side view showing an example of the arrangement of protrusions.

FIG. 23 is a plan view of an example of a protrusion.

FIG. 24 is a plan view of an example of a protrusion.

FIG. 25 is a plan view of an example of a protrusion.

FIG. 26 is an enlarged perspective view showing an example of an arrangement state of protrusions.

FIG. 27 is an enlarged perspective view showing an example of an arrangement state of protrusions.

FIG. 28 is a perspective view for explaining the dimensions of each part of the V-shaped projection according to the present invention.

FIG. 29 is a plan view for explaining the area of the magnetic disk.

FIG. 30 is an enlarged view for explaining an area of a magnetic disk.

FIG. 31 is an enlarged view showing an arrangement state of protrusions formed on the inner peripheral side of the magnetic disk.

FIG. 32 is an enlarged view showing the arrangement of protrusions formed on the outer peripheral side of the magnetic disk.

FIG. 33 is a graph showing a flying limit of a magnetic head at which an AE signal starts to be detected with respect to a height of a protrusion formed on a magnetic disk in a test 1;

34 is a graph showing the attraction force with respect to the height of a protrusion formed on a magnetic disk in Test 1. FIG.

FIG. 35 is a graph showing a relationship between a texture pitch and a coercive force in Test 2.

FIG. 36 is a graph showing a relationship between a center of roughness of a texture, a maximum height thereof, and a critical flying height in Test 3.

FIG. 37 is a graph showing the relationship between the density of protrusions and the number of times CSS can be used.

FIG. 38 is a perspective view showing a magnetic head having a convex portion according to the present invention.

FIG. 39 is a perspective view showing a magnetic head on which protrusions according to the present invention are formed.

FIG. 40 is a side view of a main part of the magnetic head shown in FIG. 39;

FIG. 41 is a bottom view of an essential part of the magnetic head shown in FIG. 39;

FIG. 42 is a perspective view showing an example of a magnetic head on which protrusions are formed.

FIG. 43 is a perspective view showing an example of a magnetic head on which protrusions are formed.

44A and 44B are views for explaining a conventional magnetic disk, in which FIG. 44A is a side sectional view, and FIG. 44B is an enlarged side sectional view of a main part.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Magnetic head 2a Slider 2b Core part 4 Magnetic disk 5 Projection 5a Air compression part 10 Magnetic disk 11 Projection 12 Texture 12A Texture 22 Projection 23 Projection 24 Projection 25 Projection 25a Air compression part 26 Projection 26a Air compression Unit 27 Projection 27a Air compression unit 28 Projection 28a Air compression unit 29 Projection 29a Air compression unit 30 Projection 31 Projection 32 Projection 33 Projection 34 Projection 35 Projection 35a Air compression unit 36 Projection 36a Air compression Section 37 Projection 37a Air compression section 38 Projection 38a Air compression section 39 Projection 39a Air compression section 40 Projection 40a Air compression section 42 Projection section 45 Projection 46 Projection 48 Magnetic head 49 Projection 50 Magnetic head 56 Projection 56a Air compressor 60 Magnetic head 3 the height of the projections 70 the height d 'protrusion of the magnetic head 73 protrusion 80 magnetic disk 88 texture 90 magnetic disk 91 protrusion 92 Texture 92A Texture d projections

Claims (10)

(57) [Claims] In a magnetic disk on which information is read and written by a magnetic head and which is driven to rotate, a plurality of protrusions are formed on a surface of the magnetic disk with which the magnetic head comes into contact when the rotation of the magnetic disk is stopped. At the top,
0.001 to 1 protrusions / n with an average diameter of 10 to 500 nm
A magnetic disk characterized in that m ^{2 is} formed. 2. A magnetic disk, on which information is read and written by a magnetic head and which is driven to rotate, has a plurality of protrusions formed on a surface of the magnetic disk with which the magnetic head contacts when the rotation of the magnetic disk is stopped. On the top, 0.001 to 1 protrusions / nm ² having an average diameter of 10 to 500 nm are provided.
Formed on the magnetic recording portion of the magnetic disk surface,
A magnetic disk having fine grooves formed in a circumferential direction. 3. A magnetic disk according to claim 1, wherein the height of the protrusion formed on the magnetic disk according to claim 1 is 5 nm or more. 4. The magnetic disk according to claim 2, wherein the average pitch of the fine grooves formed along the circumferential direction is 2 μm or less. 5. The magnetic disk according to claim 2, wherein the difference between the average height and the maximum height of the surface on which the fine grooves are formed along the circumferential direction is 40 nm or less. Magnetic disk. 6. A magnetic disk on which information is read and written by a magnetic head and which is driven to rotate, comprising: a protrusion provided on at least one of a front surface and a rear surface of the magnetic disk, with an air compression portion facing forward in the rotation direction of the magnetic disk Are formed, and the average diameter is 1 at the top of the projection.
A magnetic disk, wherein 0.001 to 1 protrusions / nm < ² > of 0 to 500 nm are formed. 7. The magnetic head floats and travels during rotational driving.
In a magnetic disk with which a magnetic head comes into contact when rotation is stopped, at least one of a front surface and a back surface of the magnetic disk has a plurality of protrusions formed by connecting two or more air guide portions in a mutually inclined state in a crotch-open manner. Each projection is formed with the open side facing forward in the rotation direction of the magnetic disk, and a projection having an average diameter of 10 to 500 nm is formed on the top of the projection in a range of 0.001 to 1.
A magnetic disk characterized by being formed in pieces / nm ² . 8. The magnetic disk according to claim 6, wherein the protrusions formed on the inner peripheral side of the magnetic disk are formed smaller than the protrusions formed on the outer peripheral side of the magnetic disk and are densely arranged. Or a magnetic disk according to 7. 9. A flies from the magnetic disk of the rotary drive state, a magnetic head which contacts the magnetic disk in a stopped state, the magnetic disk side of the array of magnetic heads
A protrusion having an air compression portion facing the rear side in the rotation direction of the magnetic disk is formed on the magnetic disk portion. On the top of the protrusion, there are 0.001-1 protrusions / nm having an average diameter of 10 to 500 nm / nm. ^Two
A magnetic head characterized by being formed. 10. A flies from the magnetic disk of the rotary drive state, a magnetic head which contacts the magnetic disk in a stopped state, the magnetic disk side Le of the magnetic head
The Lumpur section, projections made by connecting the shaped opening crotch in mutually inclined state two or more air guide is one or more, the rotation direction rear side of each protrusion is a magnetic disk that open side Formed on the top of the protrusion, having an average diameter of 10 to 500 nm.
Characterized in that 0.001 to 1 protrusions / nm ^{2 are} formed.