JP2001014665A - Master information carrier and regeneration treatment of the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a master information carrier having a structure in which impurities and dust are hardly adhered to the carrier and a method for efficiently carrying out regeneration treatment of the master information carrier having a constitution easily removing impurities and dust. SOLUTION: A ferromagnetic thin film 1 having a shape pattern corresponding to a digital information signal array is formed on the surface of a non- magnetic substrate 2, a hard protective film 4 is formed on a surface thereof and a lubricant 3 is applied on the hard protective film 4 to form a master information carrier. The surface of the master information carrier is treated with varnish, the lubricant washed in a solvent is removed, and then the lubricant is reapplied onto the ferromagnetic thin film and the non-magnetic substrate to carry out regeneration treatment of the master information carrier.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a master information carrier used for statically recording a digital information signal on a magnetic recording medium in a batch manner, and a method of reproducing the master information carrier.

[0002]

2. Description of the Related Art At present, magnetic recording / reproducing apparatuses tend to have a high recording density in order to realize a small size and a large capacity.
In the field of hard disk drives, which are typical magnetic storage devices, devices exceeding the areal recording density of 3 Gbit / in ² have already been commercialized, and in a few years, the practical application of 10 Gbit / in ² will be discussed. Rapid technological progress is recognized.

[0003] As a technical background enabling such a high recording density, the improvement of the medium performance, the head-disk interface performance, and the improvement of the linear recording density due to the emergence of a new signal processing system such as a partial response are also significant. Is a factor. However, in recent years, the trend of increasing the track density greatly exceeds the trend of increasing the linear recording density, and is a main factor for improving the areal recording density. This is due to the practical use of a magnetoresistive element type head which is much more excellent in reproduction output performance than a conventional inductive type magnetic head.
At present, the practical use of the magnetoresistive element type head makes it possible to reproduce a track width signal of only a few μm or less with good S / N. On the other hand, it is expected that the track pitch will reach the submicron range in the near future with further improvement in head performance in the future.

In order for the head to accurately scan such a narrow track and reproduce a signal with good S / N, the tracking servo technology of the head plays an important role. With regard to such tracking servo technology, in a current hard disk drive, a tracking servo signal, an address information signal, a reproduction clock signal, and the like are recorded at a constant angular interval in one round of the disk, that is, within 360 degrees in angle. (Hereinafter, referred to as a preformat). By reproducing these signals at regular intervals, the magnetic head can accurately scan the track while confirming and correcting the position of the head.

The above-described tracking servo signal, address information signal, reproduction clock signal, and the like serve as reference signals for the head to accurately scan the track. Required. In a current hard disk drive, after a disk is incorporated in the drive, preformat recording is performed by a magnetic head whose position is strictly controlled using a dedicated servo recording device.

Conventionally, there have been the following problems in preformat recording of a servo signal, an address information signal, and a reproduced clock signal by a magnetic head using the above-described dedicated servo recording device.

First, recording with a magnetic head is basically line recording based on the relative movement between the head and the medium. Therefore, in the above-described method of performing recording while strictly controlling the position of the magnetic head using a dedicated servo recording device, preformat recording requires a lot of time, and the dedicated servo recording device is considerably expensive. This results in a very high cost.

Secondly, because of the spread of the recording magnetic field due to the spacing between the head and the medium and the pole shape of the recording head,
There is a point that the magnetization transition at the end of the track on which the preformat recording is performed lacks sharpness. The current tracking servo technology detects the position of the head based on the amount of change in the reproduction output when the head scans off the track. Therefore, the signal track recorded in the preformat is not only excellent in S / N when the head accurately scans the track as in reproducing the data information signal recorded between the servo areas, but also in the head. Is required to have a steep reproduction output change amount when scanning off the track, that is, off-track characteristics. The above-mentioned problem is contrary to this requirement, and makes it difficult to realize an accurate tracking servo technique in future submicron track recording.

As means for solving the problem of the preformat recording by the magnetic head as described above, the present inventors have proposed:
In Japanese Patent Application Laid-Open No. 10-45544, a ferromagnetic thin film on the surface of a master information carrier is brought into contact with a surface of a master information carrier having a ferromagnetic thin film pattern corresponding to an information signal formed on the surface of a substrate. A preformatting technique has been proposed which aims at recording a magnetization pattern corresponding to a pattern on a magnetic recording medium.

In the configuration disclosed in Japanese Patent Application Laid-Open No. 10-45544, the magnetic recording medium is provided with a ferromagnetic thin film on the master information carrier by a recording magnetic field generated from a ferromagnetic thin film on the surface of the master information carrier which is magnetized in one direction. A magnetization pattern corresponding to the thin film pattern is recorded. That is, a ferromagnetic thin film pattern corresponding to a tracking servo signal, an address information signal, a reproduction clock signal, etc. is formed on the surface of the master information carrier by photolithography technology or the like. Format recording can be performed.

[0011] Whereas the recording by the conventional magnetic head is basically a dynamic linear recording based on the relative movement between the head and the medium, the feature of the above configuration is that the recording is accompanied by the relative movement between the master information carrier and the medium. There is no static surface record. Due to such features, Japanese Patent Application Laid-Open No. 10-45544
The technology disclosed in Japanese Patent Application Publication No. JP-A-2006-15095 can exert the following extremely effective effects on the problems related to the preformat recording described above.

First, because of surface recording, the time required for preformat recording is much shorter than that of a conventional recording method using a magnetic head. Further, an expensive servo recording device for performing recording while strictly controlling the position of the magnetic head is not required. Therefore, productivity related to preformat recording can be significantly improved, and production cost can be reduced.

Second, since static recording does not involve relative movement between the master information carrier and the medium, the space between the master information carrier and the medium can be reduced by closely contacting the surface of the master information carrier and the surface of the magnetic recording medium. Can be minimized. Furthermore, unlike the recording by the magnetic head, the recording magnetic field does not spread due to the pole shape of the recording head. For this reason, the transition of the magnetization at the end of the track on which the preformat recording is performed has an excellent steepness as compared with the recording by the conventional magnetic head, and more accurate tracking is possible.

In order to obtain good recording signal quality in the technique disclosed in Japanese Patent Application Laid-Open No. 10-45544, it is necessary to provide a uniform and good recording medium over a large area between the master information carrier and the magnetic recording medium in the signal recording process. It is necessary to realize adhesion. The present inventors have disclosed in Japanese Patent Laid-Open No. 10-2
Japanese Patent Application Laid-Open No. 69566/1990 discloses that the air between the master information carrier and the magnetic disk is sucked and the pressure by the surrounding atmospheric pressure is used to absorb the warpage and surface waviness of the master information carrier and the magnetic recording medium. A technique capable of realizing good adhesion between the two has been proposed.

[0015]

On the other hand, JP-A-10-2
With the technique disclosed in Japanese Patent Application Laid-Open No. 69566/1992, the deterioration of the recording signal quality due to the warpage and the surface waviness of the master information carrier and the magnetic recording medium is improved. Deterioration of the recording signal quality due to dust or the like is recognized as a new problem. That is, as the number of times of recording on the magnetic recording medium using the master information carrier is increased, it becomes clear that impurities and dust generated by various factors adhere to the surface of the master information carrier and gradually deteriorate the recording signal quality. Was. These impurities and dusts include those generated and attached from the recording device members, those attached to dust floating in the air, those attached to the magnetic recording medium surface by transfer, and master information. Those generated from components of the carrier itself and adhered to the surface are exemplified.

The presence of such impurities and dust not only locally deteriorates the signal quality due to an increase in the spacing between the master information carrier and the magnetic recording medium, but also makes the master information carrier and the magnetic recording medium firm. This is even more serious because the close contact may cause defect damage to the magnetic recording medium. Therefore, in the master information carrier, it is preferable to perform a regenerating process for washing and removing these impurities and dust at a fixed number of recording times. However, if the regenerating process is performed frequently, the merit related to the production cost of the technology is lost. It will be broken.

From such a viewpoint, a master information carrier having a configuration to which impurities and dust are unlikely to adhere, and even if the adhesion of impurities and dust cannot be completely avoided, they are easily removed and reproduced. There is a demand for the development of a master information carrier having a configuration capable of performing this.

According to the present invention, there is provided a master information carrier having a structure to which impurities and dust are unlikely to adhere, and a structure capable of easily removing impurities and dust for reproduction. A master information carrier,
It is an object of the present invention to provide a method for efficiently reproducing these master information carriers.

[0019]

In order to achieve the above object, a master information carrier according to the present invention comprises a master in which a shape pattern corresponding to a digital information signal array is provided on the surface of a nonmagnetic substrate by an array of ferromagnetic thin films. An information carrier, wherein a hard protective film is formed on the ferromagnetic thin film and the non-magnetic substrate, and a lubricant is applied on the hard protective film.

In the master information carrier, the hard protective film is preferably formed by a sputtering method and is an amorphous thin film containing carbon as a main component.

In the master information carrier, the thickness of the hard protective film is preferably 20 nm or less.

In the master information carrier, the lubricant is preferably a composition containing perfluoropolyether (PFPE).

Next, a first reproduction processing method of the master information carrier of the present invention is a method of reproducing the master information carrier by removing impurities and / or dust attached to the surface of the master information carrier, The method includes a step of washing and removing the lubricant in a solvent, and a step of re-coating the lubricant on the ferromagnetic thin film and the nonmagnetic substrate.

Next, a second reproduction method of the master information carrier of the present invention is a method of reproducing the master information carrier by removing impurities and / or dust attached to the surface of the master information carrier, A step of burnishing the master information carrier surface, a step of washing and removing the lubricant in a solvent, and a step of re-applying the lubricant on the ferromagnetic thin film and the non-magnetic substrate. .

[0025]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described in detail below, together with the functions and effects provided by the structure of the present invention.

First, FIG. 6 shows an example of a configuration of a master information signal pattern provided by a ferromagnetic thin film pattern on the surface of the master information carrier of the present invention. FIG. 6 shows, for example, a master information signal pattern formed by a ferromagnetic thin film pattern in a preformat area provided at a constant angle in a circumferential direction (ie, a track length direction) of a disk-shaped magnetic recording medium. In other words, only 10 tracks are shown in the track width direction. For reference, a track portion serving as a data area on the disk medium after the master information signal is preformat-recorded on the disk medium is indicated by a broken line.

The master information signal pattern is, for example, as shown in FIG.
As shown in (1), each area of a clock signal, a tracking servo signal, an address information signal, and the like is sequentially arranged in the track length direction. In the master information carrier of the present invention, the master information signal pattern
For example, in the configuration example shown in FIG. 6, a hatched portion is a portion formed of a ferromagnetic thin film. The other portion is a portion made of a non-magnetic substrate or another non-magnetic material deposited on the non-magnetic substrate.

The actual master information carrier has all recording tracks in the circumferential direction of the disk at regular intervals and in the radial direction of the disk medium, corresponding to the recording area of the magnetic disk medium where the master information signal is recorded. For example, a master information signal pattern as shown in FIG. 6 is formed.

In the master information carrier of the present invention, a hard protective film is formed on the master information signal pattern shown in FIG. 6, and a lubricant is applied on the hard protective film. The coating thickness of the lubricant is preferably in the range of 1 to 10 nm.

FIG. 1 shows a configuration example of a cross section in the bit length direction (track length direction) of the master information carrier of the present invention. The cross-sectional configuration example shown in FIG. 1 corresponds to the cross section taken along dashed-dotted line AA ′ shown in FIG.

The master information carrier of the book shown in FIG. 1 is created, for example, by the following procedure. First, a ferromagnetic thin film 1 is deposited on the surface of a planar non-magnetic substrate 2, and a resist pattern corresponding to a digital information signal is formed on the surface by a lithography technique such as photolithography. next,
After forming a concavo-convex pattern corresponding to the resist pattern on the ferromagnetic thin film 1 by a dry etching technique such as ion milling, the remaining resist film is removed. Finally, a hard protective film 4 is formed on the pattern-processed surface as described above.
Is deposited, and a lubricant 3 is applied on the surface.

FIG. 2 shows another example of the configuration of the cross section in the bit length direction (track length direction) of the master information carrier of the present invention. As in FIG. 1, the cross-sectional configuration example shown in FIG.
Corresponds to the cross section taken along dashed-dotted line AA ′ shown in FIG.

The master information carrier of the book shown in FIG. 2 is created, for example, by the following procedure. First, a resist pattern corresponding to a digital information signal is formed on the surface of the planar non-magnetic substrate 2 by a lithography technique such as photolithography, and then a concavo-convex pattern corresponding to the resist pattern is formed by a dry etching technique such as ion etching. It is formed on the base 2. Thereafter, before removing the remaining resist film, the ferromagnetic thin film 1 is deposited by a vapor deposition method such as sputtering or vapor deposition, or a plating method,
Thereafter, the remaining resist film and the unnecessary ferromagnetic thin film 1 deposited thereon are removed by a chemical treatment such as a remover.
At the time of chemical treatment, physical polishing may be used together. Finally, a hard protective film 4 is deposited on the surface patterned as described above, and a lubricant 3
Is applied.

FIG. 3 shows still another configuration example of a cross section in the bit length direction (track length direction) of the master information carrier of the present invention. As in FIGS. 1 and 2, the cross-sectional configuration example shown in FIG. 3 corresponds to the cross section taken along dashed-dotted line AA 'shown in FIG.

The master information carrier shown in FIG. 3 is created, for example, by the following procedure. First, a ferromagnetic thin film 1 is deposited on the surface of a planar non-magnetic substrate 2, and a resist pattern corresponding to a digital information signal is formed on the surface by a lithography technique such as photolithography. Next, an uneven pattern corresponding to the resist pattern is formed on the ferromagnetic thin film 1 by a dry etching technique such as ion etching.
Formed. Thereafter, before removing the remaining resist film, the nonmagnetic solid 5 was deposited by a vapor deposition method such as sputtering or vapor deposition, a plating method, or a coating technique such as spin coating, and thereafter, the remaining resist film and the remaining resist film were deposited thereon. Unnecessary non-magnetic solid layers are removed by treatment with a chemical solution such as a remover. At the time of chemical treatment, physical polishing may be used together. Finally, a hard protective film 4 is deposited on the surface patterned as described above, and a lubricant 3 is applied on the surface.

As described above, among the impurities and dusts adhering to the surface of the master information carrier, those adhering due to the recording device members, those adhering to the dust floating in the air, and those for magnetic recording In addition to the transfer and adhesion of the deposits on the medium surface, there are also those which are generated from components of the master information carrier itself and adhere to the surface. Of these, the components generated from the master information carrier itself mainly generate burrs on the processed ends of the ferromagnetic thin film 1, the non-magnetic substrate 2, and the non-magnetic solid 5 when the pattern processing accuracy is insufficient. The thin lumps remaining on the master information carrier and the magnetic recording medium are peeled off and adhered to the surface while being repeatedly and firmly adhered to each other.

On the other hand, the master information carrier of the present invention has the following functions and effects from the viewpoint of preventing the above-mentioned adhesion of impurities and dust.

First, in each of the master information carriers of the present invention illustrated in FIGS. 1 to 3, the surface of the pattern processing surface is covered with a hard protective film 4. Therefore, it is possible to effectively prevent a thin lump or the like existing inside the master information carrier itself from peeling off and attaching to the surface.

The master information carrier of the present invention illustrated in FIGS. 1 to 3 is obtained by applying a lubricant 3 on a hard protective film 4. Such a lubricant has a function of reducing the surface energy of the surface of the master information carrier, thereby making it difficult for external impurities and dust to adhere thereto. Even if impurities and dust adhere, they can be prevented from firmly adhering due to the presence of the lubricant. That is, since the adhesion of impurities and dust to the lubricant layer is very weak, it can be removed instantaneously and easily with a clean compressed air blower or the like.

As a specific example, the influence of impurities and dust adhering on the magnetic recording medium will be described. Usually, a lubricant is applied on the magnetic recording medium. When preformat recording is performed using a master information carrier having no lubricant layer on such a magnetic recording medium, impurities and dust are more easily adsorbed on the surface of the master information carrier than on the surface of the magnetic recording medium. Impurities and dust on the medium tend to transfer and adhere to the master information carrier surface side. On the contrary,
If preformat recording is performed using the master information carrier of the present invention having a surface coated with a lubricant, impurities and dust on the magnetic recording medium as described above are less likely to be transferred and adhered to the master information carrier surface. More preferably, in the process of performing preformat recording using the master information carrier of the present invention, without forming a lubricant layer on the surface of the magnetic recording medium,
With a configuration in which a lubricant is applied to the surface of the magnetic recording medium after preformat recording, impurities and dust adhering to the surface of the magnetic recording medium are less likely to be transferred and adhered to the surface of the master information carrier.

The lubricant can be used without any particular limitation as long as it can reduce the surface energy of the master information carrier and obtain the effect of preventing the adhesion of impurities and dust. Since the lubricant is in close contact with the surface of the recording medium, the lubricant applied to the surface preferably has the same main component as the lubricant applied to the magnetic recording medium. Many lubricants commonly used today for magnetic recording media are based on perfluoropolyether (PFPE), and the master information carrier of the present invention is also coated with a lubricant based on perfluoropolyether (PFPE). Can be used. In one embodiment of the present inventors, Ausimont (AUSIMONT) manufactured by "Fomblin ZDOL"
Was diluted to 500 ppm with the company's diluting solvent "GALDEN" and applied by a dip method.

The master information carrier of the present invention can be used even if impurities or dust adhering to the surface cannot be instantaneously and easily removed by a compressed air blower or the like and proper preformat recording cannot be performed. It is possible to remove and regenerate them by such a procedure.

First, the lubricant applied to the master information carrier is washed and removed in an organic solvent such as isopropyl alcohol (IPA). At this time, impurities and dust adhering to the master information carrier surface are effectively removed together with the lubricant. Thereafter, if a lubricant is applied again to the surface of the master information carrier, the master information carrier is reproduced again as a master information carrier capable of performing appropriate preformat recording.

In the case where impurities and dust are attached in a relatively large amount or firmly, the surface of the master information carrier is burnished prior to washing and removing the lubricant in a solvent, so that the surface is more complete. It is preferable because impurities and dust can be removed. Since the master information carrier of the present invention is covered with the hard protective film 4, the master information carrier surface,
Particularly, it has sufficient durability without damaging the ferromagnetic thin film pattern corresponding to the master information signal.

Various methods can be used for the burnishing process. FIG. 4 shows an example in which a burnishing head for a hard disk is used as one configuration example. FIG.
In the configuration shown in (1), a burnish head 7 for a hard disk is brought into contact with the surface of the master information carrier 6 with a constant load. The master information carrier 6 is held and rotated by a holder 8 attached to a rotating shaft 9, while the varnish head 7 is rotated in a direction 1 substantially matching the disk radial direction.
1, the burnishing head 7 can scan and burnish the entire surface of the master information carrier 6 on which the master information pattern is formed.
By the burnishing process shown in FIG. 4, impurities and dust on the surface of the master information carrier adhere to the burnishing head 7 and are removed.

The burnishing head for the hard disk is used in the final process in the manufacture of the hard disk in order to remove coarse projections and adhered foreign substances on the disk surface by the same method as the configuration illustrated in FIG. As shown in, for example, U.S. Pat.No. 4,845,816, a large number of burnishing heads for such a hard disk are commercially available in various shapes depending on the purpose. You can select and use different types. In one embodiment by the present inventors, AHEAD TECHNOL
OGY) "Waffle head F3016" was used.

As another configuration example of the burnishing process,
FIG. 5 shows an example of a burnishing process using a burnishing tape. In the configuration shown in FIG. 5, the varnish tape 12 is brought into contact with the surface of the master information carrier by a roller 13 with a constant load. Since the master information carrier is held and rotated by the holder 8 attached to the rotating shaft 9, the burnish tape 12 has a sufficient tape width in the disk radial direction,
The burnish tape 12 can burnish the entire surface of the master information carrier on which the master information pattern is formed. By the burnishing process shown in FIG. 5, impurities and dust on the surface of the master information carrier adhere to the burnishing tape 12 and are removed. At this time, by moving the varnish tape 12 in the fixed direction 14, a new tape surface free of impurities and dust is always supplied to the surface of the master information carrier, so that more efficient and highly reliable Burnishing can be performed, which is preferable.

The burnish tape 12 is obtained by dispersing and polishing abrasive grains on a tape surface made of a polymer film. The burnish tape 12 differs in composition and particle size depending on the purpose of burnishing the surface of various component materials. Many products coated with various abrasive grains are commercially available. In the burnishing treatment of the present invention, an appropriate one can be selected from these commercially available burnishing tapes according to the embodiment and used. In one example of the present inventors, a wrapping film roll “Imperial # 15000” manufactured by 3M and containing chromium oxide abrasive grains was used.

As described above, since the master information carrier of the present invention is covered with the hard protective film 4, the master information carrier can cope with the master information carrier surface, especially the master information signal, even with the above burnishing process. It has sufficient durability without damaging the ferromagnetic thin film pattern. As a thin film material suitable for such a hard protective film 4, a C film,
B film, SiO ₂ film and the like are suitable from the viewpoint of hardness. These thin films can be formed using a normal vapor deposition method such as sputtering or vapor deposition.

The formation of these hard protective films 4 increases the spacing between the master information carrier and the magnetic recording medium at the time of signal recording and increases the spacing loss at the time of recording. Therefore, the thickness of the hard protective film 4 cannot be made too large. In preformat recording on a magnetic disk mainly related to the present invention, the signal recording wavelength is about 0.3 μm or more in many cases. According to the study of the present inventors, a hard protective film thickness that is allowable from the viewpoint of recording spacing loss for this recording wavelength is:
It is about 20 nm or less, and the effect of the present invention can be sufficiently obtained without damaging the surface even when burnishing is performed in this range.

Further, as the hard protective film 4 has a certain degree of conductivity as a characteristic, the effect of suppressing the adhesion of dust can be further promoted. When the surface of the master information carrier is covered with an insulating material, static electricity may be generated on the surface, and the effect of preventing dust from being adhered may not be sufficiently obtained. On the other hand, when the hard protective film 4 has conductivity, static electricity is less likely to be generated, so that the effect of preventing dust adhesion can be more easily obtained. From such a viewpoint, as the hard protective film 4 having both hardness as the protective film and conductivity enough to suppress the adhesion of dust, amorphous C produced by the sputtering method is mainly used (usually 90% by weight or more). ) Is most suitable. Although the B film and the SiO ₂ film are sufficient in hardness, they are difficult to obtain the effect of preventing dust from adhering due to their high insulating properties. Further, even if the film is mainly composed of the same C, for example, a C film manufactured by using a plasma CVD method has a diamond structure,
Although it is more excellent in hardness than the sputtered carbon film, the insulating property is increased and the effect of preventing dust adhesion cannot be obtained.

Although the embodiments of the present invention have been described above, the configuration of the present invention can be applied to various embodiments. For example, in the present specification, the description has been made mainly on application to a magnetic disk medium mounted on a hard disk drive or the like, but the present invention is not limited to this, and a flexible magnetic disk, a magnetic card Also, the present invention can be applied to a magnetic recording medium such as a magnetic tape, and the effects of the invention can be obtained in the same manner as described above.

The information signals recorded on the magnetic recording medium have been described with a focus on preformat signals such as a tracking servo signal, an address information signal, and a reproduced clock signal. The applicable information signal is not limited to the above. For example, it is possible in principle to record various data signals, audio and video signals using the configuration of the present invention. In this case, the master information carrier of the present invention and the recording technology on the magnetic recording medium using the master information carrier enable mass production of soft disk media to be produced and can be provided at low cost.

[0054]

According to the present invention, there is provided a preformat recording technique for performing static batch recording of preformat information signals such as a servo signal for tracking, an address information signal, and a reproduction clock signal on a magnetic recording medium. Information carrier that has a configuration that hardly adheres dust and dust,
Further, it is possible to provide a method for efficiently reproducing a master information carrier by easily removing impurities and dust.
As a result, it is possible to suppress the deterioration of the recording signal quality due to impurities and dust interposed between the master information carrier and the magnetic recording medium at the time of preformat recording, and perform more reliable preformat recording. Become.

[Brief description of the drawings]

FIG. 1 is a partially enlarged cross-sectional view showing one configuration example of a cross section in the bit length direction of a master information carrier of the present invention.

FIG. 2 is a partially enlarged cross-sectional view showing another configuration example of a cross section in the bit length direction of the master information carrier of the present invention.

FIG. 3 is a partially enlarged cross-sectional view showing still another configuration example of a cross section in the bit length direction of the master information carrier of the present invention.

FIG. 4 is a schematic diagram showing a configuration example of a burnishing process of a master information carrier using a burnishing head in the master information carrier reproduction processing method of the present invention.

FIG. 5 is a schematic diagram showing a configuration example of a burnishing process of a master information carrier using a burnishing tape in the method of reproducing a master information carrier according to the present invention.

FIG. 6 is a partially enlarged plan view showing one configuration example of a master information signal pattern on the master information carrier of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Ferromagnetic thin film 2 Nonmagnetic base 3 Lubricant 4 Hard protective film 5 Nonmagnetic solid 6 Master information carrier 7 Burnish head 8 Holder 9 Rotation axis 10 Master information carrier rotation direction 11 Burnish head moving direction 12 Burnish tape 13 Roller 14 Moving direction of burnish tape

Continued on the front page (72) Inventor Hideyuki Hashi 1006 Kadoma, Kazuma, Osaka Prefecture Inside Matsushita Electric Industrial Co., Ltd. 5D006 AA01 AA02 AA05 AA06 BB07 DA03 EA03 FA00

Claims (6)

[Claims] 1. A master information carrier in which a shape pattern corresponding to a digital information signal array is provided on a surface of a non-magnetic substrate by an array of ferromagnetic thin films, wherein a hard protection is provided on the ferromagnetic thin film and the non-magnetic substrate. A master information carrier, wherein a film is formed and a lubricant is applied on the hard protective film. 2. The hard protective film according to claim 1, wherein the hard protective film is formed by a sputtering method and is an amorphous thin film containing carbon as a main component.
A master information carrier according to 1. 3. The master information carrier according to claim 1, wherein the thickness of the hard protective film is 20 nm or less. 4. The lubricant is a perfluoropolyether (P
2. The master information carrier according to claim 1, which is a composition containing FPE). 5. A method for regenerating a master information carrier by removing impurities and / or dust adhering to the surface of the master information carrier according to claim 1, wherein a step of washing and removing a lubricant in a solvent is provided. Reapplying a lubricant on the magnetic thin film and the non-magnetic substrate. 6. A method for regenerating a master information carrier by removing impurities and / or dust adhering to the surface of the master information carrier according to claim 1, wherein the step of subjecting the surface of the master information carrier to burnishing includes: A method for regenerating a master information carrier, comprising: a step of washing and removing an agent in a solvent; and a step of recoating a lubricant on a ferromagnetic thin film and a nonmagnetic substrate.