JPH06103617A - Stamper for optical disk and production of substrate - Google Patents

Abstract

PURPOSE:To provide a master disk and stamper having excellent adhesiveness and to prolong the life thereof by forming an oxide thin film to serve as a layer to be peeled on a photosensitive resin and further forming an org. thin film adjacent thereto at the time of forming the stamper and substrate for optical disks. CONSTITUTION:Rugged patterns for guide grooves and information recording are formed by using the photosensitive resin on the surface of one master disk 3 and an SiO2 film 13 is laminated on the surface thereof at the time of forming an optical disk stamper. The surface is then treated with a fluorine compd. 12, by which the surface energy is previously lowered. A liquid acrylic UV curing resin 5 is thereafter dropped and a transparent member 6 coated with an adhesion accelerator on one surface is superposed thereon and is irradiated with UV rays 7 to cure the resin 5. The resin is peeled to form the stamper 8. The SiO2 film 13 is laminated on the surface of the stamper 8 and is treated with a fluorine compd. 12 at the time of forming an optical disk substrate. The substrate 11 consisting of the resin 9 on which the rugged patterns of the stamper 8 has been transferred, is obtd. by the similar stages.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing an optical disk, and more particularly to a method for manufacturing a stamper and a substrate for an optical disk, which is suitable for improving the life of the master and the stamper.

[0002]

2. Description of the Related Art In a conventional process, as shown in FIG. 3, a photosensitive resin 2 is applied to a substrate 1 having a smooth and flat surface,
A master 3 is produced in which at least one of a guide groove and a concave-convex pattern in which information is recorded is formed on the surface of the photosensitive resin 2 by optical means. After that, the Teflon film 4 (or Al
Film) as a release layer, the liquid ultraviolet curable resin 5 is applied to the surface of the release layer, and the translucent member 6 is superposed and adhered, and then ultraviolet rays 7 are irradiated from the back of the translucent member 6. Then, the ultraviolet curable resin 5 is cured and peeled from the boundary surface between the ultraviolet curable resin 5 and the Teflon film 4 (or Al film),
The stamper 8 to which at least one of the guide groove and the concavo-convex pattern in which information is recorded is manufactured. here,
The shape of the above-mentioned concavo-convex pattern is inverted and formed. Furthermore, the Teflon film 4 (or Al film) is also formed on the stamper surface.
Is formed as a release layer, a liquid ultraviolet curable resin 9 is applied to the surface of the release layer, and the translucent substrate 10 is superposed and brought into close contact with the translucent substrate 10. The cured resin 9 is cured and peeled off from the boundary surface between the ultraviolet curable resin 5 and the ultraviolet curable resin 9 to manufacture the optical disk substrate 11 in which at least one of the guide groove and the concave-convex pattern in which information is recorded is duplicated ( JP-A 1-107
Nos. 338 and 1-107339).

[0003]

In the prior art described above, when Teflon is used as the peeling layer, the Teflon and the ultraviolet curable resin can be peeled off easily. However, the adhesiveness between the surface of the photosensitive resin on the master and the release layer is not sufficient. That is,
When the master and the stamper are separated at the end of the stamper manufacturing process, stress is applied to the surface. As a result, a part of the release layer of the master was peeled off and transferred to the stamper after the stamper was manufactured several times, making it impossible to duplicate the stamper. Further, when Al is used as the release layer, there is a problem that the life of the master is very short because the adhesiveness is sufficient but it is easily corroded. Further, these problems are also the same in the step of producing a replica from the stamper.

For this reason, in a manufacturing process in which a large number of stampers are manufactured from a single master and the large number of stampers are attached to a rotary drum as shown in FIG. , Has become a big problem. Also, if the master and stamper surfaces have fine roughness,
In this method, this roughness is directly transferred to the stamper and the ultraviolet curable resin layer of the substrate. When a recording film is formed on the ultraviolet curable resin layer, the fine roughness is reflected in the recording film. Since an optical disc records / reproduces information based on the intensity change of the laser beam applied to the recording film, the fine roughness of the recording film surface as described above causes noise and deteriorates the information recording / reproducing characteristics. There's a problem.

An object of the present invention is to provide a method of manufacturing a master and a stamper which are excellent in life and performance.

[0006]

In order to achieve the above object, the present invention provides an oxide thin film on the surface of a master or stamper having a photosensitive resin film on which at least one of a guide groove and an uneven pattern for recording information is formed. After stacking
The organic thin film is laminated adjacent to the oxide thin film,
At least one of the stamper surface and the oxide thin film surface is ion-etched. That is, on the surface of the above-mentioned photosensitive resin film or stamper, after forming an oxide excellent in adhesiveness with the photosensitive resin or stamper and not easily corroded into a thin film by a vapor deposition method or a sputtering method,
On the surface of the oxide thin film or the stamper, an organic material having good releasability from the ultraviolet curable resin is formed into a thin film by an evaporation method or a coating method.

If at least one of the surface of the master, the surface of the stamper and the surface of the oxide thin film is subjected to ion etching in the above manufacturing method, fine roughness on each surface is almost eliminated and the surface becomes extremely smooth. Unless excessive etching is performed, the shape of the unevenness representing information such as the guide groove does not change. The etching may be performed using an etching solution, but ion etching (sputter etching with a reactive gas or an inert gas, ion beam etching, ion milling) is preferable.

The above oxides include SiO, SiO ₂ and Ti.
O ₂ , Al ₂ O ₃ , Ta ₂ O ₅ , SnO ₂ , MnO, ZrO ₂ ,
At least one selected from the materials having a composition close to that of MgO and Y ₂ O ₃ or a mixed material thereof is used. More preferably, those containing SiO, SiO ₂ , TiO ₂ and Al ₂ O ₃ as main components are used. A material containing a fluorine-based compound as a main component is used for the organic thin film.

[0009]

[Function] An oxide thin film is laminated on the surface of a master having a photosensitive resin film on which at least one of a guide groove and an uneven pattern for recording information is formed, by an evaporation method or a sputtering method, and then adjacent to the oxide thin film. The operation of the present invention will be described by taking as an example the case where the organic thin film is formed by the evaporation method, the coating method or the like.

An oxide thin film is provided on the photosensitive resin in order to increase the adhesion to the photosensitive resin while maintaining the ease of peeling the Teflon. Further, a fluorine-based compound is attached on the oxide thin film and heat-treated to chemically bond it. The interface between the photosensitive resin and the oxide thin film is also excellent in adhesiveness. Therefore, by providing the release layer having this structure, the release layer can be easily released from the interface between the master and the stamper, and a large number of stampers can be transferred without missing the release layer.
In addition, the same effect can be obtained by stacking an oxide thin film on the surface of the ultraviolet curable resin of the stamper as a release layer of the stamper by this method and then stacking an organic thin film adjacent to the oxide thin film.

Further, when at least one of the surfaces of the master, the stamper and the oxide thin film is ion-etched in the manufacturing method, the fine roughness on the surface causes the convex portions to be etched faster than the concave portions. There is almost no difference between the parts, making it extremely smooth. In addition, since the ion-etched surface is extremely active, there is a secondary effect that the adhesion with the next laminated film is improved.

[0012]

【Example】

Example 1 As shown in FIG. 1, a substrate (glass: 10
t) a photosensitive resin (photoresist MP-14
00, manufactured by Shipley Co., Ltd.) 2 and a SiO ₂ film (30) by a sputtering method on the surface of the master 3 having at least one of the guide groove and the concavo-convex pattern in which information is recorded.
nm) 13 is laminated, and the surface of the SiO ₂ film 13 is further treated with the fluorine-based compound 12 to reduce the surface energy. Specifically _{F (CF 2) 8 - (} CH 2) 2 -Si (OCH 3) 3 solution or spin-coating, or evaporated SiO ₂
The surface was covered with this molecule and then heat-treated at 100 ° C. for 10 minutes.

By this surface treatment, the SiO ₂ surface has a contact angle with water of about 110 degrees, and the surface energy is lowered, and the peeling force from the ultraviolet-curing resin material is about 100% as compared with the untreated master. It was confirmed to be 1/10. Further, since the fluorine-based compound was chemically bonded to the SiO ₂ surface by the heat treatment, the release layer was not detached in the transfer process, and about 50 stampers could be produced, and it was possible to produce more. During the fluorine compound treatment, it is necessary to accurately control the amount of adhesion so that the uneven pattern of information is not filled. In addition to the above compounds, commercially available fluorine-based coating agents and siloxane-based treatment agents also had similar effects.

After that, a liquid acrylic ultraviolet curable resin 5 is dropped, and an adhesion promoter for promoting adhesion with the ultraviolet curable resin is applied on one side of the transparent member 6 (polymethylmethacrylate). : 2t) were overlapped and made parallel and flat, and ultraviolet rays 7 were irradiated from the back side of the translucent member 6 (irradiation power: 4 kw / cm ² , irradiation time: 30 seconds) to cure the ultraviolet curable resin. After that, UV curable resin 5
When peeled off at the interface between the fluorine-containing compound 12 and the fluorine-based compound 12, a stamper 8 made of the ultraviolet curable resin 5 having the uneven pattern of the master 3 transferred onto the translucent member 6 was obtained.

The sputtering conditions for forming the SiO ₂ film were as follows.

Degree of ultimate vacuum: 1 × 10 ⁻⁵ Torr or less Introduced gas: Ar Introduced gas pressure: 2 × 10 ⁻³ Torr or more and 5 × 10 ⁻² Torr or less Input power: ² to 30 w / cm ² The sputtering conditions depend on the apparatus, and therefore the conditions shown above are not limited. In addition to the above SiO ₂ , SiO, TiO ₂ , Al ₂ O ₃ , Ta ₂ O ₅ , SnO ₂ , M
The same effect was obtained with a two-layer structure using nO, ZrO ₂ , MgO and Y ₂ O ₃ .

Example 2 Further, a SiO ₂ film (30 nm) 13 was laminated on the surface of the stamper 8 manufactured as shown in FIG. 2 by the sputtering method in the same manner as the above method, and further the SiO ₂ film 13 was formed. Fluorine-based compound 12 on the surface
Processed in. After that, a liquid acrylic UV-curable resin 9 is dropped, and an adhesion promoter for promoting adhesion with the UV-curable resin is applied on one side of the translucent substrate 1.
0 (glass: 1t) is overlapped to make it parallel and flat, and ultraviolet rays 7 are irradiated from the back side of the transparent substrate 10 (irradiation power: 4k
This UV curable resin 9 was cured by applying w / cm ² , irradiation time: 30 seconds). Then, when peeled off at the boundary surface between the ultraviolet curable resin 9 and the fluorine-based compound 12, the optical disk substrate 11 made of the ultraviolet curable resin 9 having the uneven pattern of the stamper 8 transferred onto the transparent substrate 10 was obtained. The peeling force from the stamper 8 at this time was about 1/10 of that of the untreated stamper, and the peeling layer was not separated during the transfer process.

<Embodiment 3> A SiO ₂ film (3) was formed on the surface of the master 3 prepared in the same manner as in Embodiment 1 by a sputtering method.
0 nm) 13 was laminated, and the surface of the SiO ₂ film 13 was further treated with the siloxane-based treatment agent 12 ′ as in Example 1. Also by this, the same effect as in Example 1 was obtained.

<Embodiment 4> A SiO ₂ film (30 nm) 13 is laminated on the surface of a stamper 8 manufactured in the same manner as in Embodiment 1 by the sputtering method in the same manner as above.
Further, the surface of the SiO ₂ film 13 was treated with the siloxane-based treating agent 12 'as in the third embodiment. After that, the optical disk substrate 11 was manufactured in the same manner as in Example 2. With this, the same effect as in Example 2 was obtained.

<Embodiment 5> The surface of the master 3 produced in the same manner as in Embodiment 1 was sputter-etched. By this etching, the convex portions having a fine roughness on the surface are etched faster than the concave portions, so that there is almost no difference between the concave portions and the convex portions, and the surface becomes extremely smooth. After this, a SiO ₂ film (30 nm) 13 is formed on the surface of the master 3 by the sputtering method.
Was laminated, and the surface of the SiO ₂ film 13 was further treated with a fluorine-based compound 12 to prepare a stamper 8 in the same manner as in Example 1 or 3. Further, since the ion-etched surface is extremely active, the adhesion with the next laminated film is improved.

The etching conditions for etching the photosensitive resin were as follows.

Degree of ultimate vacuum: 1 × 10 ^-5 Torr or less Introduced gas: Ar Introduced gas pressure: 2 × 10 ^-3 Torr or more and 5 × 10 ^-2 Torr or less Input power: ² to 30 w / cm ² Since the etching conditions depend on the material to be etched and the sputtering apparatus, the conditions shown above are not limited. In addition to the above SiO ₂ , SiO, T
iO ₂ , Al ₂ O ₃ , Ta ₂ O ₅ , SnO ₂ , MnO, ZrO
_A similar effect was obtained with a two-layer structure using ₂ , MgO and Y ₂ O ₃ . Further, even if the stamper surface was sputter-etched, fine roughness could be smoothed, and the same effect was obtained.

<Embodiment 6> A SiO ₂ film (3) is formed on the surface of the master 3 prepared in the same manner as in Embodiment 1 by a sputtering method.
0 nm) 13 was laminated, and the surface of the SiO ₂ film was further sputter-etched. By this etching,
Since the convex portion having a fine roughness on the surface is etched faster than the concave portion, there is almost no difference between the concave portion and the convex portion, and the surface becomes extremely smooth. After that, a SiO ₂ film (30 nm) 13 is laminated on the surface of the master 3 by a sputtering method, and the surface of the SiO ₂ film 13 is treated with a fluorine-based compound 12 in the same manner as in the first or third embodiment. 8 was produced. Further, since the ion-etched surface is extremely active, the adhesion with the next laminated film is improved.

The etching conditions for etching the SiO ₂ film were as follows.

Degree of ultimate vacuum: 1 × 10 ⁻⁵ Torr or less Inlet gas: Ar Inlet gas pressure: 2 × 10 ⁻³ Torr or more and 5 × 10 ⁻² Torr or less Input power: ² to 30 w / cm ² Since the etching conditions depend on the material to be etched and the sputtering apparatus, they are not limited to the above-mentioned conditions. In addition to SiO ₂ , SiO, Ti
O ₂ , Al ₂ O ₃ , Ta ₂ O ₅ , SnO ₂ , MnO, ZrO ₂ ,
A similar effect was obtained with a two-layer structure using MgO and Y ₂ O ₃ . Further, even if SiO ₂ formed on the surface of the stamper was sputter-etched, fine roughness could be smoothed, and the same effect was obtained. The surfaces of the master and stamper were sputter-etched and further laminated S
Similar effects were obtained by sputter etching the iO ₂ surface.

[0026]

According to the present invention, in a method of manufacturing a stamper and a substrate for an optical disc, an oxide thin film is formed as a release layer on a photosensitive resin, and an organic thin film is formed adjacent to the oxide thin film. As a result, it is possible to obtain a long-life master and stamper having excellent adhesion to the master and stamper and having a peeling layer having good peelability from the ultraviolet curable resin. Further, the surface smoothing by ion etching makes it possible to obtain a substrate with lower noise.

[Brief description of drawings]

FIG. 1 is a sectional view showing a method for manufacturing an optical disk stamper according to a first embodiment of the present invention.

FIG. 2 is a sectional view showing a method for manufacturing an optical disc substrate according to a second embodiment of the present invention.

FIG. 3 is a cross-sectional view showing a conventional method for manufacturing an optical disk stamper and a substrate.

FIG. 4 is a sectional view showing a continuous replica manufacturing apparatus.

[Explanation of symbols]

3 ... Master, 5 ... UV curable resin, 6 ... Translucent member, 7 ...
UV rays, 8 ... Stamper, 12 ... Fluorine compound, 13 ...
SiO ₂ film.

Front page continuation (72) Inventor Yoshinori Miyamura 1-280 Higashi Koikekubo, Kokubunji, Tokyo Inside Hitachi Central Research Laboratory (72) Inventor Keikichi Ando 1-280 Higashi Koikeku, Kokubunji, Tokyo Hitachi Central Research Institute In-house

Claims (8)

[Claims] 1. A method for producing a stamper for an optical disc having a resin layer on which at least one side of a base material is provided with irregularities representing information, wherein a master having a photosensitive resin on which the irregularities representing information are formed. After laminating an oxide thin film on the surface and laminating an organic thin film adjacent to the oxide thin film, a resin layer on which unevenness representing information is transferred from the master is formed on at least one surface of the base material. A method for producing a characteristic stamper for an optical disk. 2. The oxide thin film according to claim 1, wherein the oxide thin film is Si.
O, SiO ₂ , TiO ₂ , Al ₂ O ₃ , Ta ₂ O ₅ , Sn
A method for manufacturing an optical disk stamper comprising at least one layer selected from O ₂ , MnO, ZrO ₂ , MgO and Y ₂ O ₃ . 3. The method for manufacturing an optical disk stamper according to claim 1, wherein the organic thin film is a fluorine-based compound. 4. The method for producing a stamper for an optical disk according to claim 1, wherein at least one of the photosensitive resin having the irregularities representing the information and the oxide thin film laminated thereon is ion-etched. 5. A method for producing an optical disk substrate having a resin layer having irregularities representing information on at least one surface of the substrate, wherein the resin layer having the irregularities representing the information transferred from a master is used as the substrate. An oxide thin film is laminated on the surface of the stamper formed on at least one surface of the substrate, and an organic thin film is laminated adjacent to the oxide thin film. A method for manufacturing a substrate for an optical disk, which is characterized in that it is formed on one surface. 6. The oxide according to claim 5, wherein the oxide is SiO 2,
SiO ₂ , TiO ₂ , Al ₂ O ₃ , Ta ₂ O ₅ , SnO ₂ , M
A method for producing a substrate for an optical disc comprising at least one layer selected from nO, ZrO ₂ , MgO and Y ₂ O ₃ . 7. The method for manufacturing an optical disk substrate according to claim 5, wherein the organic substance is a fluorine compound. 8. The method for producing an optical disk substrate according to claim 5, wherein at least one of the stamper resin layer having the irregularities representing the information and the oxide thin film laminated on the resin is ion-etched.