JPH0765302A - Magnetic recording medium and manufacturing method thereof - Google Patents

Abstract

(57) [Abstract] [Purpose] A highly accurate tracking control is performed by providing uneven pits capable of magnetically detecting tracking information or ROM information on a magnetic recording medium, and a ROM containing information such as computer software. To provide a magnetic recording medium as a replica. [Structure] In a magnetic recording medium, magnetically reproducible information is provided in advance on a substrate by means of unevenness. Servo information is provided in the first area, and ROM information such as computer software is provided in the second area following the uneven information, and the method is read by a magnetic head and a disk manufacturing method thereof. [Effect] A large number of replica magnetic recording media containing information such as computer software can be manufactured at low cost.

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 in which information can be magnetically recorded and reproduced by using a magnetic head and can be duplicated, and a method of manufacturing the same.

[0002]

2. Description of the Related Art In a magnetic disk device that magnetically records and reproduces digital information by using a magnetic head, a soft program of a personal computer or the like has a method in which a user magnetically copies a floppy disk to a magnetic disk medium. Has been. That is, the fixed information peculiar to the computer could not be replica-formed in advance on the magnetic disk.

[0003]

As described above, conventionally, it has been impossible to form a replica of fixed information peculiar to a computer on a magnetic disk in advance.
For the PC software, it was necessary to purchase the software recorded on the floppy disk in advance and transfer the information from the floppy disk to the magnetic disk, which was a complicated task.
As the scale of the software increases, the number of floppies increases to tens, which reduces the operability of the device and makes it difficult for the user to use.

Moreover, in the magnetic disk medium, it is necessary to sputter a magnetic film on a disk substrate, for example, an aluminum substrate, to initially magnetize it, and then to initialize it one by one with a magnetic head by a servo writer or a magnetic recording device. It has been difficult to reproduce a large number of magnetic disk media having

A first object of the present invention is to transfer the software recorded on a floppy disk to a magnetic recording medium by forming desired information such as fixed information peculiar to a computer in advance on the magnetic recording medium. The object is to provide a magnetic recording medium that is convenient and easy to use.

A second object of the present invention is that the first area (ROM area) which is magnetically detectable and contains the information recorded by locally removing the magnetic film and the user record and reproduce the information. It is an object of the present invention to provide a manufacturing method capable of easily duplicating a magnetic recording medium having a possible second area (RAM area).

[0007]

A magnetic recording medium according to the present invention comprises a first area (ROM area) in which magnetically reproducible information is provided in advance, and a first area in which a user can magnetically record and reproduce information. 2 area (RAM area). The information in the first area (ROM area) can be duplicated even though it can be magnetically reproduced,
It is preferable to record fixed information peculiar to the device to be used such as software peculiar to the computer in this ROM area.

According to one characteristic, the first region (R
The OM area) and the second area (RAM area) are angle-divided and mixed.

According to another feature, the first region (RO
In the M region), the magnetically reproducible information is replica-created by partially removing the magnetic film.
Further, in the first area (ROM area), a large number of magnetically reproducible servo marks replica-created by partially removing the magnetic film are periodically provided along a track. The magnetically reproducible information is provided between the marks.

According to another feature, the second area (RA
Also in the (M region), a large number of magnetically reproducible servo marks replica-created by partially removing the magnetic film are periodically provided along the track, and these servo marks are used as user information recording regions. To do.

According to the manufacturing method of the present invention, the first area (ROM area) containing the information that is magnetically detectable and the magnetic film is locally removed and the user records the information magnetically. A magnetic recording medium having a reproducible second area (RAM area) is produced by a replica.
In particular, the magnetically reproducible information recorded in the first area (ROM area) and the first area (ROM area) and / or the second area (RAM area) are periodically arranged along the track. It is characterized in that a large number of magnetically reproducible servo marks and replicas are created. That is, a pattern of information to be provided in advance on the magnetic recording medium, for example, magnetically reproducible information provided in advance in the first area (ROM area) or the first area (ROM area).
And / or a mask having a pattern of magnetically reproducible servo marks periodically provided along the track in the second area (RAM area) is prepared, and the resist provided on the magnetic thin film is used as the mask. Through the resist, the resist corresponding to the pattern is removed, and the magnetic thin film corresponding to the pattern is removed by etching using the resist as a mask to remove the first region (RO
A magnetic recording medium in which the M area) and the second area (RAM area) are mixed is created. The mask is
The mask has a pattern formed by irradiating a substantially uniform amount of light with the feed pitch of the optical system for irradiating the light spot being smaller than the light spot diameter.

[0012]

According to the magnetic recording medium of the present invention, magnetically reproducible information is provided in the first area (ROM
Area) and a second area where the user can magnetically record and reproduce information.
Area (RAM area), the fixed information peculiar to the device to be used such as software unique to the computer is recorded in this first area (ROM area) so that the user can copy the software program etc. There is no need to magnetically copy from the disc to the magnetic recording medium.
Moreover, the information in the first area (ROM area) can be duplicated even though it can be magnetically reproduced, and the magnetic recording medium of the present invention can be inexpensively produced by the replica technique.

Further, by providing a large number of servo marks in the first area (ROM area) and the second area (RAM area) periodically along, for example, concentric circles or spiral tracks, the servo marks are formed. The generated magnetic flux distribution is magnetically detected by the magnetic head to obtain a tracking signal, and information is recorded in the second area (RAM area) or the first area (ROM area) while controlling the servo position of the magnetic head. Information in the area) can be read out.

According to the manufacturing method of the present invention, the first area (ROM area) containing the information which is magnetically detectable and the magnetic film is locally removed and recorded and the user magnetically records the information. It is possible to easily create a magnetic recording medium having a second area (RAM area) in which recording and reproduction can be performed. Moreover, since a mask having a pattern of information to be provided in advance on the magnetic recording medium can be used a plurality of times, a large number of magnetic recording media having the same pattern can be accurately produced.

[0015]

1 and 5 show an embodiment of a magnetic recording medium according to the present invention. A magnetic disk 1 has a magnetic film capable of magnetically recording and reproducing information, and a user can magnetically record information. It has a second area (RAM area) 2 in which recording / reproduction is possible and a first area (ROM area) 3 in which magnetically reproducible information is provided in advance. In FIG. 1, the RAM area 2
Is provided on the outer peripheral side, and the ROM area 3 is provided on the inner peripheral side.
In FIG. 5, the RAM area 2 is provided on the outer peripheral side, the ROM area 3 is provided on the inner peripheral side, and the ROM area 3 is the RAM.
The region 2 is angle-divided and mixed. RAM area 2
The ROM area 3 is provided with concentric or spiral tracks, and data is recorded / reproduced and / or reproduced along the tracks.

FIG. 2 shows data recording tracks in the RAM area 2. In FIG. 2, each of the data tracks 4 and 4'is composed of a combination of a plurality of servo marks 5 periodically provided along the tracks and RAM data 6 recorded in a user information recording area between the servo marks 5. ing. The servo marks 5 are formed by locally removing the magnetic film by etching.
The magnetic head magnetically samples the distribution of the magnetic flux generated in the magnetic head to obtain a tracking signal, and while controlling the servo position of the magnetic head based on the tracking signal, the desired RAM data is recorded in the user information recording area between the servo marks 5. (For example, code data) 6 is recorded or reproduced along the center lines of the tracks 4 and 4 '. The magnetic film is a magnetic thin film for in-plane recording, and the RAM data 6 is magnetically recorded and reproduced in-plane by the magnetic head. As the servo mark 5, a pair of pits distributed to the left and right with respect to the center lines of the tracks 4 and 4'or a pit row having different frequencies and / or different phases provided on the left and right sides of the track center line The following tracking mark is used.

FIG. 3 shows a data reproduction-only track in the ROM area 3. In FIG. 3, the data tracks 4 and 4 ′ are a combination of a plurality of servo marks 5 periodically provided along the tracks and read-only ROM data (for example, code data) 7 provided between the servo marks 5. It is composed of. Servo mark 5 and R
The OM data 7 are both formed by locally removing the magnetic film by etching. A magnetic head magnetically samples and detects a magnetic flux distribution generated in these servo marks 5 to obtain a tracking signal, and while controlling the servo position of the magnetic head based on the tracking signal, the ROM data 7 between the servo marks 5 is tracked. Play along the 4, 4'centerline. The ROM data 7 is only reproduced by the magnetic head and is not recorded by the magnetic head.

FIG. 4 is a diagram for explaining the sectional structure of the servo mark 5 and the ROM data 7 and the reproducing operation by the magnetic head. In FIGS. 4A and 4B, each pit 9 forming the servo mark 5 and the ROM data 7 is a magnetic film 16
Are not locally removed by etching. Now the magnetic film 16
Is initially magnetized in one direction 10, positive and negative magnetic poles are formed on both edges 11 and 12 of each pit 9, and a magnetic field is generated in the pit portion. Such a pit 9 can be magnetically reproduced by scanning the pit 9 with a magnetic head and detecting the magnetic flux 13 formed in the magnetic head core 14 when the magnetic head passes through the pit 9 by the magnetic coil 15. The ROM data 7 can be read while magnetically detecting the tracking signal from the mark 5.

A method of manufacturing the magnetic recording medium shown in FIGS. 1 and 5 will be described with reference to FIGS. 6 and 7. FIG. 6 shows a photomask recording apparatus used in the manufacturing method of the present invention.
In this recording device, a pattern of information to be provided in advance on the magnetic recording medium 1 by the ultraviolet laser light on the chrome photomask 130, that is, magnetically reproducible ROM data 7 provided in advance in the ROM area 3 and the ROM area 3 are provided.
And / or a pattern composed of a plurality of magnetically reproducible servo marks 5 periodically provided along the track in the RAM area 2 is recorded. In FIG. 6, the chrome photomask 130 is fixed to a rotary bearing to rotate. On the other hand, laser light such as argon laser (w = 0.45 micron) is intensity-modulated by an optical modulator,
When condensing with a high NA (eg NA = 0.93) lens,
A circular spot having a diameter of about 0.4 micron is formed on the rotary mask 130. Now, assuming that the pits 9 forming the ROM data 7 and the servo marks 5 are long in the radial direction of the disk, for example, 5 μm, a vertically long pit cannot be formed with a circular spot of 0.4 μm. Figure 6
(b) shows the principle for forming a vertically long pit. Figure 6
In (a), the optical system is mounted on a movable base and the photomask 130 is mounted.
Although it moves linearly in the disk radial direction, it is advisable to control the moving speed so that the photomask 130 moves by a distance smaller than the light spot diameter, for example, by an amount substantially corresponding to the radius of the light spot during one rotation. Then Fig. 6
As shown in (b), the integrated value of the amount of light with which a desired portion of the photomask 130 is irradiated becomes a uniform rectangle. Now, in order to set the light spot diameter to 0.4 micron and form a vertically long pit of 5 micron, the moving amount of the optical system is 0.2 micron /
Rotate 5 / 0.2 = 25, that is, photomask 13
Light may be emitted at a desired timing while 0 is rotated 25 times.

Pits 9 constituting the servo mark 5 and the ROM data 7 shown in FIGS. 2 and 3 by the apparatus of FIG.
The mask 130 on which the pattern composed of the columns is recorded is developed, and a magnetic recording medium is produced by the process shown in FIG. 7 which is an embodiment of the present invention. In FIG. 7A, a ferromagnetic film 16 is formed on a disk substrate 1 made of aluminum or glass, a positive resist 140 is applied thereon, and a photomask 130 is contact-exposed. In FIG. 7B, after exposing the positive resist 140, the resist in the pit portion is dissolved by development. In FIG. 7C, the ferromagnetic film 16 in the pit portion is etched by using the positive resist 140 as a mask to remove the magnetic film 16 in the pit portion by, for example, an ion milling method. Then, as shown in FIG. 7D, the resist 140 is removed with a plasma asher or an organic solvent.

As described above, according to the method of manufacturing the magnetic recording medium shown in FIGS. 6 and 7, the magnetically detectable magnetic film shown in FIG. 1 or 5 is locally removed. A magnetic recording medium having a ROM area 3 containing recorded information and a RAM area 2 in which a user can magnetically record / reproduce information can be created by a replica.

The information 7 in the first area (ROM area) 3 and the servo mark 5, which are provided in advance on the magnetic recording medium, need only be magnetically reproducible and reproducible. The magnetic film is not limited to the one obtained by locally removing the magnetic film.

[0023]

According to the present invention, a ROM is provided on a magnetic recording medium.
Not only can information be recorded in replicas at low cost,
Since ROM information and RAM information are mixed, when used in a device such as a personal computer, a software program or the like can be preliminarily formed in the magnetic recording medium as ROM information. Therefore, a floppy is used to copy the software to the magnetic recording medium. You can save time.

Further, by providing a large number of servo marks in advance in the first area (ROM area) and the second area (RAM area), the magnetic flux distribution generated in the servo marks is magnetically generated by the magnetic head. The information can be recorded / reproduced in the second area (RAM area) or the information in the first area (ROM area) can be read while detecting the servo position and controlling the servo position.

[Brief description of drawings]

FIG. 1 is a diagram showing an embodiment of a magnetic recording medium of the present invention.

FIG. 2 is a diagram showing a data recording track in a RAM area.

FIG. 3 is a diagram showing a data reproduction-only track in a ROM area.

FIG. 4 is a diagram for explaining the operation principle of magnetic signal reproduction used in the present invention.

FIG. 5 is a diagram showing an example of a magnetic recording medium of the present invention.

FIG. 6 is a diagram for explaining one embodiment of a magnetic recording medium manufacturing method according to the present invention.

FIG. 7 is a diagram for explaining an embodiment of the magnetic recording medium manufacturing method according to the present invention.

Claims (8)

[Claims] 1. In a magnetic recording medium having a magnetic film and capable of magnetically recording and reproducing information, magnetically reproducible information is provided in advance in a first area (ROM area) and a user information. Second area (RA
M region). 2. In a magnetic recording medium having a disk structure having a magnetic film and capable of magnetically recording and reproducing information, a first area (RO) provided with magnetically reproducible information in advance.
A magnetic recording medium characterized in that an M area) and a second area (RAM area) where information can be magnetically recorded and reproduced by a user are mixed by being angularly divided. 3. The magnetic recording according to claim 1, wherein the magnetically reproducible information is recorded in the first area by partially removing the magnetic film. Medium. 4. A plurality of magnetically reproducible servo marks recorded by partially removing the magnetic film are periodically provided along the track in the first region, and between the servo marks. The magnetic recording medium according to claim 1, wherein the magnetically reproducible information is provided. 5. A plurality of magnetically reproducible servo marks, which are recorded by partially removing the magnetic film, are periodically provided along the track in the second region, and the servo marks are provided between the servo marks. The magnetic recording medium according to claim 1, wherein the magnetic recording medium is a user information recording area. 6. The method of manufacturing a magnetic recording medium according to claim 1, wherein a mask having an information pattern provided in advance in the first area is prepared.
The resist provided on the magnetic film is exposed through the mask to remove the resist corresponding to the pattern,
A method of manufacturing a magnetic recording medium, characterized in that the magnetic film corresponding to the pattern is removed using the resist as a mask to form a magnetic recording medium in which the first region and the second region are mixed. 7. The pattern is formed by irradiating a substantially uniform amount of light with a feed pitch of an optical system for irradiating a light spot on the mask being smaller than a diameter of the light spot. The manufacturing method according to claim 6. 8. The manufacturing method according to claim 6, wherein the pattern includes a large number of servo marks periodically provided along a track.