JP2002269853A - Optical disk manufacturing method and optical disk manufacturing apparatus - Google Patents

Abstract

(57) [Summary] [PROBLEMS] When manufacturing an optical disk by bonding a disk substrate and a sheet, the manufacturing tact is increased while preventing air bubbles from entering during bonding. SOLUTION: After a base plate 11 and a bell jar 12 are separated and a sheet 4 is placed on a sheet placing surface 13a with an adhesive layer facing upward, a disk substrate 1 is fitted to substrate positioning pins 15. At the same time, the inside of the sub-chamber 18 is evacuated to a concave shape. After the base plate 11 and the bell jar 12 are combined, the main chamber 17 is evacuated. When the elastic film 16 becomes flat, the evacuation of the main chamber 17 is terminated, and the sub-chamber 18 is opened to the atmosphere. The elastic film 16 is expanded into the main chamber 17 to press the disk substrate 1 and press the disk substrate 1 against the sheet 4. After the compression is stabilized, the base plate 11 and the bell jar 12 are separated, and the optical disk is carried out.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical disk manufacturing apparatus and an optical disk manufacturing method, and more particularly, to an optical disk manufacturing method in which a light transmitting layer is formed by bonding a disk substrate and a light transmitting sheet. It is suitable to be applied to.

[0002]

2. Description of the Related Art In recent years, in the field of information recording, various researches and developments on an optical information recording method have been advanced in various places. This optical information recording system has an advantage that recording and / or reproduction can be performed in a non-contact manner, and that a recording density higher by one digit or more than that of a magnetic recording system can be achieved. Further, this optical information recording method has an additional advantage that it can correspond to each memory type such as a read-only type, a write-once type, and a rewritable type. Therefore, as a method for realizing an inexpensive large-capacity file, application to a wide range of uses from industrial use to consumer use is considered.

[0003] Among them, in particular, digital audio disks (DAD) and optical video disks, which are optical disks corresponding to a read-only memory mode, are widely used at present.

[0004] An optical disk such as a digital audio disk has a reflective film made of a thin metal film such as an aluminum (Al) film on a light-transmitting disk substrate on which a concavo-convex pattern such as pits or grooves indicating information signals is formed. Further, a protective film for protecting the reflective film from moisture (H ₂ O) and oxygen (O ₂ ) in the atmosphere is provided. At the time of reproducing the information signal on the optical disk, the disk substrate is irradiated with a reproduction light such as a laser beam from the disk substrate toward the concave / convex pattern, and the information signal is detected by a difference in reflectance between the incident light and the return light due to the reproduction light. I do.

When manufacturing such an optical disk, first, a disk substrate having a concavo-convex pattern is formed by an injection molding method. Next, a reflective film made of a metal thin film is formed on the optical disk substrate by a vacuum evaporation method.
Next, a protective film is formed by applying an ultraviolet curable resin to the upper layer of the reflective film.

In recent years, in such an optical information recording system, further higher recording density has been required. In order to respond to the demand for higher recording density, a technique for reducing the spot diameter of the reproduction light by increasing the numerical aperture (NA) of the objective lens used when irradiating the reproduction light with the optical pickup. Was proposed.

That is, for example, while the NA of an objective lens used for reproducing a conventional DAD is 0.45, the D has a recording capacity 6 to 8 times that of the conventional DAD.
In an optical video disc such as a VD (Digital Versatile Disc), the NA of an objective lens used at the time of reproduction is set to about 0.60 to reduce the spot diameter.

As the NA of such an objective lens is increased, the reproduced light to be irradiated is transmitted through the objective lens.
It is necessary to make the disk substrate of the optical disk thin. This is because the allowable amount of an angle (tilt angle) deviating from the perpendicular of the disk surface with respect to the optical axis of the optical pickup is reduced, and this tilt angle is affected by aberration and birefringence due to the thickness of the disk substrate. This is because it is easy to receive. Therefore, the tilt angle is made as small as possible by making the disk substrate thinner. For example, in the above-mentioned DAD, the thickness of the substrate is 1.2 m
m. On the other hand, in an optical video disc such as a DVD having a recording capacity of 6 to 8 times that of the DAD, the thickness of the substrate is about 0.6 mm.

In consideration of the demand for higher recording density in the future, it is necessary to further reduce the thickness of the substrate.
Therefore, an information signal portion is formed by forming irregularities on one main surface of the substrate, and a reflection film and a light transmission layer made of a thin film capable of transmitting laser light are sequentially laminated on the information signal portion to form a light transmission layer. There has been proposed an optical disk configured to reproduce an information signal by irradiating a reproduction light from the side. In such an optical disk in which an information signal is reproduced by irradiating reproduction light from the light transmission layer side, it is possible to cope with a high NA of the objective lens by reducing the thickness of the light transmission layer. .

However, when the thickness of the light transmitting layer is reduced, it is difficult to form the light transmitting layer by injection molding using a thermoplastic resin, which is generally used for manufacturing optical disks. That is, it is very difficult to form a light-transmitting layer of about 0.1 mm that maintains good transparency while maintaining low birefringence by employing the conventional technique.

Therefore, a method has been devised in which the light transmitting layer is formed of an ultraviolet curable resin. However, when the light transmitting layer is formed of an ultraviolet curable resin, it is very difficult to make the light transmitting layer to have a uniform film thickness on the substrate surface. Therefore, it is difficult to stably reproduce the information signal.

[0012]

Then, using a bonding apparatus having a pad made of an elastic material and a flat stage made of a metal, the light is pressed in vacuum by a pressing mechanism such as an air cylinder. A method has been proposed in which a light transmitting layer is bonded by pressing a transparent sheet and a substrate. Here, the bonding apparatus will be specifically described below with reference to the drawings.

That is, as shown in FIG. 15, in a conventional bonding apparatus, a plane stage 102 is provided on a base plate 101. A bracket 1 made of metal is provided at a position facing the flat stage 102.
A pad 104 made of an elastic material and having a conical shape with a radius of curvature of 100 mm is fixed to a surface of the bracket 103 facing the flat stage 102. The bracket 103 and the pad 1
04 is stored in the bell jar 105. The open end of the bell jar 105 has an O-ring 106 for sealing.
Is provided. Then, the bell jar 105 is pressed against the base plate 101 via the O-ring 106 so that the base plate 101 and the bell jar 10 are pressed.
5 constitutes a closed chamber.

The bracket 103 has a pad 10
An air cylinder 108 is connected via a connection cylinder 107 on a surface opposite to the surface on which the surface 4 is provided. The air cylinder 108 is mounted on the bracket 103
Is moved in a direction perpendicular to the plane of the flat stage 102, and is configured so that a predetermined pressing force can be applied to the bracket 103 via the connection cylinder 107.

A vacuum pump 110 is connected to a side wall of the bell jar 105 through an exhaust passage 109.
This vacuum pump 110 evacuates the inside of a chamber composed of the bell jar 105 and the base plate 101 to the exhaust path 1
09 for evacuating. Further, a branch exhaust path 1 that is branched in a T-shape in the middle of the exhaust path 109 is provided.
09a is provided. The branch exhaust path 109a is for opening the inside of the bell jar 105 in a closed state to the atmosphere. Further, the branch exhaust path 1 in the exhaust path 109
09a between the branch of 09a and the vacuum pump 110.
1, a valve 112 is provided between a portion connected to the bell jar 105 and a branch portion of the branch exhaust path 109a, and a valve 113 is provided in the branch exhaust path 109a. By these valves 111, 112, 113,
Evacuation and opening to the atmosphere inside the sealed state between the bell jar 105 and the base plate 101 can be controlled.

The flat stage 102 on the base plate 101 is for placing a sheet 114 thereon. Then, the upper surface of the flat stage 102 is
4 is a sheet placing surface 102a on which the sheet 4 can be placed. A center pin 115 is provided on a portion of the flat stage 102 facing the pad 104. An embedded spring (not shown) is connected to a portion of the center pin 115 on the flat stage 102 side, and is configured to be movable in a direction in which the center pin 115 protrudes and is buried with respect to the flat stage 102. . The diameter of the center pin 115 is the same as that of the through hole 1 at the center of the sheet 114 described above.
It is configured to be substantially equal to the diameter of 14a. Then, the sheet 114 is fitted to the center pin 115 so that the sheet 114 is
2 so as to be able to be mounted thereon. Further, a columnar substrate positioning pin 11 is provided above the center pin 115.
6 are provided. The diameter of the board positioning pin 116 is configured to be substantially equal to the diameter of the center hole 117a of the disc board 117. The disc board 117 is centered while the center of the disc board 117 is aligned with the center of the sheet 114. The upper end of the outer periphery of the pin 115 is configured to be supported. In the flat stage 102 thus configured, the substrate positioning pins 116
Thus, a predetermined clearance can be maintained between the disk substrate 117 and the sheet 114.

When the disk substrate 117 and the sheet 114 are bonded using the bonding apparatus configured as described above, first, the sealed state of the base plate 101 and the bell jar 105 is released, and then the sheet 114 is bonded.
Is mounted on the flat stage 102 by fitting the through-hole 114 a to the center pin 115. At this time, the sheet 114 is placed so that the bonding surface 114b faces the pad 104.

Next, the disk substrate 117 is mounted on the stepped portion (upper end of the outer peripheral portion) of the center pin 115 by fitting the center hole 117a of the disk substrate 117 to the substrate positioning pin 116. At this time, the disk substrate 117 is supported by the center pins 115 such that the recording surface 117b on which the information signal portion is provided faces the bonding surface 114b of the sheet 114.

Next, the base plate 101 is moved to the lower part of the space of the bell jar 105 (open end side), and the base plate 101 and the bell jar 105 are sealed with an O-ring 106 therebetween. This forms a chamber. Thereafter, the vacuum pump 110 is operated with the valves 111 and 112 opened, and the inside of the chamber formed by the base plate 101 and the bell jar 105 is evacuated.

Next, the air cylinder 108 is operated,
The pad 104 is moved toward the flat stage 102 via the connection cylinder 107 (downward in FIG. 15). As a result, the apex of the pad 104 first presses the substrate positioning pin 116. Next, the portion to be pressed is sequentially expanded toward the outer peripheral side, and
The center pin 115 is made to enter the plane stage 102 via. Accordingly, the clearance between the disk substrate 117 and the sheet 114 gradually decreases, and the disk substrate 117 and the sheet 114 are sequentially pressed from the inner circumference to the outer circumference, and finally the recording surface 117b and the adhesive surface 114 are bonded.
b is bonded. After the compression is stabilized, the pad 104 is moved in a direction away from the flat stage 102 by the air cylinder 108 and the connection cylinder 107 to release the compression.

Next, after closing the valve 111, the valve 1
By opening 13, the space between the bell jar 105 and the base plate 101 is opened to the atmosphere. Thereafter, the base plate 101 is separated from the bell jar 105, and after moving the base plate 101 to a predetermined position,
Using a predetermined transfer device (not shown), the compressed disk substrate 117 and the sheet 114 are placed on the flat stage 102.
Remove from

As described above, the optical disk having the light transmitting layer provided on the recording surface 117b of the disk substrate 117 by bonding the disk substrate 117 and the sheet 114 is manufactured.

When the light transmitting layer is formed by bonding the disk substrate 117 and the sheet 114 using the bonding apparatus as described above, the bonding is performed in a vacuum, so that the disk substrate 117 and the sheet 114 are bonded together. This has the advantage that air bubbles can be prevented from entering between them. In addition, by using the conical pad 104, the disk substrate 117 can be sequentially bonded to the sheet 114 from the center hole 117a toward the outer periphery, so that the adhesive surface 114b is less likely to be blocked by the adhesive. Also, there is an advantage that uneven bonding is hardly generated.

However, when the above-described conventional bonding apparatus is used, the air cylinder 1 is pressed to press the pad 104 made of an elastic body against the disk substrate 117.
08 and a pressing mechanism such as the connection cylinder 107 are required. Therefore, the size of the bonding apparatus becomes extremely large, and it is difficult to make the bonding apparatus compact and save space.

Further, the pad 104 and the bracket 1
03 needs to be stored inside the bell jar 105. Therefore, the base plate 101 and the bell jar 10
5, the space formed when the chamber is in a closed state, that is, the volume inside the chamber becomes extremely large. Then, since the volume inside the chamber is increased, there is a problem that it takes a long time to evacuate the chamber and reach a desired degree of vacuum.

Further, a pad 1 having a conical shape is provided.
04 is pressed against the disk substrate 117 to perform pressure bonding. Therefore, when the disk substrate 117 is pressed against the sheet 114 by pressing the pad 104, the disk substrate 11 is pressed.
The force acting on 7 is strong around the center hole 117a and weak at the periphery. Thus, the disk substrate 117
There is a problem that it is very difficult to make the pressure applied to the radial direction uniform in the radial direction.

Accordingly, an object of the present invention is to improve the production efficiency by increasing the tact time in the manufacturing process in an optical disk in which a light transmitting layer is formed on a disk substrate by laminating a disk substrate and a sheet. As well as preventing air bubbles from entering between the disk substrate and the light transmitting layer, thereby suppressing the occurrence of wrinkles and uneven bonding during the formation of the light transmitting layer, and making it thinner and smaller in birefringence. An optical disc manufacturing apparatus and an optical disc manufacturing apparatus having a light transmitting layer having good transparency and a uniform thickness, capable of coping with an increase in the NA of an objective lens, and capable of efficiently manufacturing an optical disc having high reliability. It is to provide a method.

Another object of the present invention is to provide an optical disk manufacturing apparatus in which a light transmitting layer is formed on a disk substrate by laminating a disk substrate and a sheet. In addition to preventing wrinkles and uneven adhesion during layer formation and preventing bubbles from entering between the disk substrate and the light transmitting layer, the tact in the manufacturing process can be shortened and production efficiency can be improved. Another object of the present invention is to provide an optical disk manufacturing apparatus that can be reduced in size and space.

[0029]

Means for Solving the Problems To achieve the above object, a first invention of the present invention is to provide a disk substrate with:
A light transmission device configured to transmit at least a laser beam used for recording and / or reproduction of an information signal on one main surface on which an information signal unit configured to record and / or reproduce an information signal is provided. And a light-transmitting sheet that can be bonded to one main surface of the disk substrate and can be bonded through a bonding layer to an adhesive layer that is configured to transmit laser light. An apparatus for manufacturing an optical disk, comprising: a pressing unit configured to be able to press the other main surface opposite to one main surface of the disk substrate, wherein the pressing unit is configured to be openable to the atmosphere and capable of being depressurized. And a partition provided between a first processing chamber configured to allow a disk substrate and a sheet to be placed thereon, and a second processing chamber configured to be openable to the atmosphere and depressurized. Is, the partition portion is an elastic body, the first
By setting the pressure inside the processing chamber to be smaller than the pressure inside the second processing chamber, the partition portion can be pressed against the other main surface of the disk substrate.

In the first aspect of the invention, typically, the disk substrate has a planar annular shape, and the sheet has a planar annular shape. The central axis and the central axis of the sheet in a direction perpendicular to the surface of the sheet are arranged so as to be coincident with each other. Further, in the first invention, preferably, one main surface of the disk substrate and the adhesive layer of the sheet are configured to be installed apart from each other while being substantially parallel to each other. The distance between the sheet and the sheet can be set to be 1.0 mm or more and 5.0 mm or less. Further, in the first invention, typically, the partition portion has a flat disk shape, and the center of the flat disk shape of the partition portion is aligned with a center axis in a direction perpendicular to one main surface of the disk substrate. When the partition is pressed against the other main surface of the disk substrate, preferably, the pressure inside the first processing chamber is made smaller than the pressure inside the second processing chamber. The partition portion is configured to be rotationally symmetric with respect to the center axis of the disk substrate. Also,
In the first invention, specifically, the partition portion is made of an elastic film, and the elastic modulus of the outer peripheral portion of the elastic film is larger than the elastic modulus of the inner peripheral portion of the elastic film, or The elastic modulus of the outer peripheral portion of the film is smaller than the elastic modulus of the inner peripheral portion of the elastic film.

In the first invention, typically, there is provided a sheet holding means configured to hold a sheet, and the sheet holding means includes a disk substrate holding portion configured to hold a disk substrate; A disk outer peripheral supporting portion configured to support an outer peripheral portion of the disk substrate is provided, the disk outer peripheral supporting portion is configured to be buried and protrudable with respect to the sheet holding means, The projecting direction is inclined toward the center of the disk substrate holding means. In the first invention,
Preferably, an opening is formed at the center of the disk substrate, and the disk substrate holding portion is configured to be fittable into the opening of the disk substrate, and is held by fitting the opening of the disk substrate to the disk substrate holding means. . And, preferably,
The disk outer periphery support portion is composed of a plurality of pins, and more preferably, the plurality of pins are provided along a virtual circumference concentric with the center of the disk substrate holding means. Are provided at the positions of the vertices of a regular polygon inscribed in the virtual circumference.

In the second invention, typically, the distance between the other main surface of the disk substrate and the partition is 5 mm or more and 70 mm or less.

In the first invention, preferably, the first
The inside of the processing chamber can be pressurized to a pressure higher than the atmospheric pressure.

According to a second aspect of the present invention, there is provided an information signal section capable of recording and / or reproducing information signals on one principal surface of a disk substrate, and recording and / or reproducing information signals.
Alternatively, a light transmission layer configured to be capable of transmitting laser light used for reproduction is provided by being sequentially laminated, and the light transmission layer is
At least, a light-transmitting sheet capable of transmitting laser light,
A laser light transmitting adhesive layer for adhering the light transmitting sheet to one main surface of the disk substrate; and pressing one main surface of the disk substrate against at least a sheet comprising the light transmitting sheet and the adhesive layer. A method for manufacturing an optical disk having a step of bonding a sheet and a disk substrate, comprising: a first processing chamber configured to be able to store a sheet and a disk substrate while being able to depressurize and open to the atmosphere; And a second processing chamber configured to be open to the atmosphere, a partition made of an elastic body,
By making the pressure inside the first processing chamber smaller than the pressure inside the second processing chamber, it presses against the other main surface opposite to the one main surface of the disk substrate, thereby reducing the The surface and the adhesive layer of the sheet are pressure-bonded.

In the second invention, typically, the disk substrate has a planar annular shape, the sheet has a planar annular shape, and the central axis of the disk substrate in a direction perpendicular to the surface of the disk substrate. And the center axis of the sheet in the direction perpendicular to the surface of the sheet is aligned. Also, in the second invention, typically, one main surface of the disk substrate and the adhesive layer of the sheet are placed apart from each other while being kept substantially parallel to each other. Is 1.0 mm or more and 5.0 mm or less.

[0036] In the second invention, preferably, the partition section is configured so that a pressure inside the first processing chamber is smaller than a pressure inside the second processing chamber, thereby forming the partition section into a disk substrate. When pressed against the other main surface of the elastic film, the elastic film is configured to be rotationally symmetric with respect to the center axis of the disk substrate. Make it larger than the elastic modulus of the inner peripheral part.

In the second aspect of the present invention, preferably, the partitioning section makes the pressure inside the first processing chamber smaller than the pressure inside the second processing chamber, thereby forming the partitioning section on the disk substrate. When pressed against the other main surface of the elastic film, the elastic film is configured to be rotationally symmetric with respect to the center axis of the disk substrate. Make it smaller than the elastic modulus of the inner peripheral part.

[0038] In the second invention, typically, there is provided a sheet holding means configured to hold a sheet, and the sheet holding means includes a disk substrate holding portion configured to hold a disk substrate; A disk outer peripheral supporting portion configured to support an outer peripheral portion of the disk substrate is provided, the disk outer peripheral supporting portion is configured to be buried and protrudable with respect to the sheet holding means, The projecting direction is inclined toward the center of the disk substrate holding unit.

In the second invention, typically, as the disk substrate is pressed by the partition, the disk outer peripheral support moves to the outer peripheral side of the disk substrate, and the disk disk is pressed before the disk substrate is completely pressed. The support by the outer peripheral support portion is released. In the second invention, preferably, at the start of pressing, the interval between the outer peripheral portion of the disk substrate and the outer peripheral portion of the sheet is 1.0 mm or more and 5.0 mm or less. Further, the sheet is fixed by suction by the sheet holding means.

In the second invention, typically, the distance between the other main surface of the disk substrate and the partition is 5 mm or more and 7 mm or more.
0 mm or less.

In the second invention, preferably, the second
Is pressurized to a pressure higher than the atmospheric pressure. Specifically, the pressure inside the second processing chamber is set to 151988 Pa or more and 506625 Pa or less (1.5 to 5 atm) at the time of bonding the disk substrate and the sheet.

In the second invention, typically, when the disk substrate is bonded to the sheet, the pressure in the first processing chamber is set to 4.0 × 10 ² Pa to 2.0 × 10 ⁴ Pa.
Do the following.

In the present invention, typically, the elastic body is silicone rubber or nitrile rubber, but other elastic materials may be used.

In the present invention, the adhesive layer is typically made of a pressure-sensitive adhesive (PSA), but it is also possible to use an ultraviolet curable resin or the like.

In the present invention, in order to minimize warpage and distortion in the manufactured optical disk, preferably,
The light transmitting sheet is made of the same material as the material used for the substrate. The thickness of the light-transmitting sheet is typically configured to be smaller than the thickness of the substrate, and is specifically selected from 30 μm or more and 150 μm or less.
In the present invention, specifically, a low water-absorbing resin such as polycarbonate (PC) or a cycloolefin polymer is used for the disk substrate, and the light-transmitting sheet is preferably the same as the disk substrate. It is composed of materials. As a material used for the substrate, a substrate made of a metal such as aluminum (Al), a glass substrate, or a substrate made of a resin such as polyolefin, polyimide, polyamide, polyphenylene sulfide, or polyethylene terephthalate (PET) is used. It is also possible. The light transmitting sheet is typically made of a polycarbonate resin, but can be made of another resin material.

In the present invention, even in the case where a foreign matter is present on the mounting surface of the sheet holding means, the sheet is preferably protected by light to prevent the foreign matter from affecting the light transmitting sheet. It comprises a transparent sheet, an adhesive layer, and a protective layer for protecting the light transparent sheet provided on the surface of the light transparent sheet opposite to the side on which the adhesive layer is provided. The protective layer is preferably made of a polyethylene terephthalate (PET) sheet or a polyethylene naphthalate (PEN) sheet. More specifically, a second adhesive is applied to at least one surface of a protective film such as a PET sheet or a PEN sheet,
The surface to which the second adhesive is applied is adhered to one surface of the light-transmitting sheet to form a sheet to be bonded to the disk substrate.

In the present invention, typically, the light-transmitting sheet is formed of a GaN-based semiconductor laser (emission wavelength: 400 nm band, blue emission) and a ZnSe-based semiconductor laser (emission wavelength: at least used for recording / reproducing information signals). 500n
a non-magnetic material capable of transmitting laser light emitted from an m-band, green) or an AlGaInP-based semiconductor laser (emission wavelength: about 635 to 680 nm, red);
Specifically, it is made of a thermoplastic resin having optical transparency such as polycarbonate.

The present invention preferably employs a DVR (Digital V
It can be applied to an optical disc having a thin light transmission layer, such as an ideo recording system, and has an emission wavelength of 650 nm.
A so-called DVR-red configured to record and reproduce information signals using a semiconductor laser of about m, and a configuration configured to record and reproduce information signals by using a semiconductor laser with an emission wavelength of about 400 nm. So-called DV
It is possible to apply to an optical disc such as R-blue. This DVR is preferably configured such that an information signal can be recorded using an objective lens whose NA is increased to about 0.85 by combining two lenses in series. And has a storage capacity of about 22 GB. An optical disk to which the present invention is preferably applied, such as the DVR, is preferably housed in a cartridge, but the application of the present invention is not necessarily limited to the one housed in a cartridge.

According to the optical disk manufacturing method and the optical disk manufacturing apparatus of the present invention configured as described above, the disk substrate is sheeted by utilizing the pressure difference between the first processing chamber and the second processing chamber. With this configuration, it is not necessary to use a large pressing unit, and the force acting on the disk substrate can be made uniform over the entire surface.

[0050]

Embodiments of the present invention will be described below with reference to the drawings. In all the drawings of the following embodiments, the same or corresponding portions are denoted by the same reference numerals.

First, an optical disk according to the first embodiment of the present invention will be described. FIG. 1 shows an optical disk according to the first embodiment.

As shown in FIG. 1, in the optical disk according to the first embodiment, the disk substrate 1 has a center hole 1b formed at the center of the replica substrate 1a.
The information signal section 1c is provided on one main surface on which unevenness is formed. Further, a light transmitting layer 2 is provided on one main surface of the disk substrate 1. The light-transmitting layer 2 is formed by bonding a light-transmitting sheet 2a via an adhesive layer 2b, and has a through-hole 2c at the center thereof.

Further, a clamp region 3 is set in an annular shape around the through hole 2c on the main surface of the light transmitting layer 2 on the light transmitting sheet 2a side. Here, the innermost diameter of the annular clamp region 3 is, for example, 23 mm,
The outermost diameter is, for example, 33 mm. On the main surface of the light transmitting layer 2 of the light transmitting layer 2 in the clamp area 3 on the side of the light transmitting sheet 2a, a clamp reference for clamping or placing an optical disk on a spindle (neither is shown) of a recording / reproducing apparatus. The surface 3a is set. In view of the fact that the light transmissive sheet 2a is adhered to one main surface of the disc substrate 1 via the adhesive layer 2b, the through holes 2c
Is selected to be equal to or larger than the diameter of the center hole 1b of the disk substrate 1, for example, equal to or larger than 15 mm. Considering that the clamp reference surface 3a is constituted by the main surface of the light transmitting layer 2 on the light transmissive sheet 2a side, the diameter of the through hole 2c is equal to or less than the innermost circumference of the clamp region 3, specifically, for example, 2
3 mm or less.

Next, a description will be given of a method of manufacturing the optical disk according to the first embodiment configured as described above. FIG. 2 shows a disk substrate serving as a base of the optical disk, and FIG. 3 shows a sheet constituting a light transmitting layer. FIG. 4 shows a flowchart of a manufacturing process of the optical disk.

First, in step ST1 shown in FIG. 4, the disk substrate 1 shown in FIG. 2 is manufactured.

That is, first, as shown in FIG. 2, the replica substrate 1a is formed by an injection molding method using a stamper provided with predetermined irregularities, or an injection molding method using a mold in which irregularities are directly formed. Make it. Also, this replica substrate 1
The thickness of a is selected in the range of 0.6 to 1.2 mm. As the material of the replica substrate 1a, a low water-absorbing resin such as polycarbonate (PC) or cycloolefin polymer (for example, ZEONEX (registered trademark)) is used. The optical disk according to the first embodiment is configured to record / reproduce an information signal by irradiating a laser beam to the disk substrate 1 from the side where the thin light transmitting layer 2 is provided. I have. for that reason,
Since it is not necessary to consider whether or not the replica substrate 1a has transparency, it is also possible to use a substrate made of a metal such as Al, for example. In addition, replica substrate 1
As a, a glass substrate or a substrate made of a resin such as polyolefin, polyimide, polyamide, polyphenylene sulfide, or polyethylene terephthalate can be used. After manufacturing the replica substrate 1a in this manner, the process proceeds to step ST2 shown in FIG.

In step ST2, as shown in FIG. 2, a recording film, a reflection film, and the like are formed on the surface of the concave / convex portion formed on one main surface of the replica substrate 1a.
An information signal section 1c is formed. The information signal portion 1c includes a reflection film, a film made of a magneto-optical material, a film made of a phase change material,
Alternatively, an organic dye film or the like is provided. Among them, as a material of the reflection film, for example, Al, an Al alloy, or an Ag alloy is used. Specifically, an optical disc as a final product is a read-only type (ROM (Read
Only Memory)) In the case of an optical disc, the information signal section 1c
For example, a single-layer film or a laminated film having at least a reflective layer made of Al or the like is provided. On the other hand, when the optical disc as the final product is a rewritable optical disc, the information signal portion 1c is composed of a TbFeCo-based alloy, a TbFeCoSi-based alloy, or a TbFeCoC-based alloy.
a film made of a magneto-optical material such as an r-based alloy, GeInSb
A single-layer film or a stacked film having at least a film made of a phase change material such as a Te alloy is provided. When the optical disc as the final product is a write-once optical disc, it is composed of a single-layer film or a laminated film having at least a film made of a phase change material such as a GeTe-based material or a film made of an organic dye material. .

Here, in the disk substrate 1 according to the first embodiment, specifically, for example, a PC substrate having a planar annular shape and a thickness of 1.1 mm is used as the replica substrate 1a. The diameter (outer diameter) of the PC board is, for example, 120 mm, and the opening diameter (inner diameter) of the center hole 1b is, for example, 15 mm. Also, as the information signal unit 1c,
A reflection layer made of an Al alloy having a thickness of, for example, 100 nm, and a mixture (ZnS) of zinc sulfide (ZnS) and silicon oxide (SiO ₂ ) having a thickness of, for example, 18 nm is formed on the region of the replica substrate 1 a where the unevenness is formed. -SiO ₂ ), a phase change recording layer made of a GeSbTe alloy having a thickness of, for example, 24 nm, and a film thickness of, for example, 100 n
A laminated film in which m _second ZnS-SiO2 _second dielectric layers are sequentially laminated is used. After the disc substrate 1 is manufactured by forming the information signal portion 1c on one main surface of the replica substrate 1a as described above, the process proceeds to step ST3 shown in FIG.

In step ST3, a step of preparing a disk substrate and a sheet is performed so that the sheet 4 shown in FIG. 3 can be bonded to one main surface of the disk substrate 1 via the adhesive layer 2b. Here, a sheet used when forming the light transmitting layer 2 according to the first embodiment will be described.

As shown in FIG. 3, a sheet 4 used for forming the light transmitting layer 2 according to the first embodiment is attached to a light transmitting sheet 2a and one surface of the light transmitting sheet 2a. A pressure-sensitive adhesive (PSA). This sheet 4 has a structure punched out in a plane annular shape, similarly to the disk substrate 1, and has a through hole 2c formed in the center. Here, in the dimensions of the sheet 4, the diameter (outer diameter) of the sheet 4 is selected to be substantially the same as or smaller than the outer diameter of the disk substrate 1, specifically, for example, 120 mm, and The diameter (inner hole diameter) is selected from a range equal to or larger than the opening diameter of the center hole 1b and equal to or smaller than the innermost peripheral diameter (for example, 23 mm diameter) of the clamp region 3 and is, for example, 23 mm.

The light-transmitting sheet 2a of the sheet 4 is made of, for example, a light-transmissive thermoplastic resin which satisfies at least optical characteristics capable of transmitting laser light used for recording / reproducing. As the thermoplastic resin, a material having a heat resistance dimensional stability, a coefficient of thermal expansion, a coefficient of thermal expansion, or the like close to that of the replica substrate 1a is selected. A methacrylic resin such as methyl methacrylate) is selected. Further, the light transmitting sheet 2
The thickness of a is preferably selected from the range of 60 to 100 μm, and more preferably selected from the range of 70 to 100 μm. In the first embodiment, the light-transmitting sheet 2
Considering that a is bonded to one main surface of the disc substrate 1 via the pressure-sensitive adhesive (PSA) adhesive layer 2b, its thickness is selected to be, for example, 70 μm.
The thickness of the light transmitting sheet 2a is determined in consideration of the wavelength of the laser beam used for recording / reproducing information signals and the desired thickness of the light transmitting layer 2.

The PSA forming the adhesive layer 2b is, for example, methacrylic resin. In addition, this adhesive layer 2b
Is, for example, 30 μm. The thickness of the adhesive layer 2b and the material used as the pressure-sensitive adhesive are determined in consideration of the desired thickness of the light transmitting layer 2 and the wavelength of laser light used for recording / reproducing information signals. You. Although illustration is omitted, in a state where the sheet 4 is stored,
A protective film for protecting the sheet 4 on the side of the adhesive layer 2b is laminated.

Then, in step ST 3, the sheet 4 configured as described above is brought into a state where it can be used for bonding to the disk substrate 1. That is, first, in step S1 of another process, the adhesive layer 2b
The above-mentioned protective film laminated on is peeled off. Thereafter, the sheet 4 in a state where the protective film is peeled off
Is transported to the sheet mounting surface of the device for bonding the disk substrate 1 and the sheet 4, and is mounted at a predetermined position.

Here, the bonding apparatus according to the first embodiment will be described. FIG. 5 shows this bonding apparatus.

As shown in FIG. 5, the bonding apparatus 10 according to the first embodiment has a flat plate-shaped base plate 11 and a bell jar 12 having one open shape. I have.

A flat stage 13 is provided on the base plate 11. The flat stage 13 is for mounting the sheet 4, and the upper surface of the flat stage 13 is a sheet mounting surface 13 a on which the sheet 4 can be mounted.

A center pin 14 is provided at substantially the center of the flat stage 13 on the side of the sheet mounting surface 13a. And this center pin 1
4 is configured to be movable in a direction in which it projects and is buried with respect to the plane stage 13. That is, the flat stage 1
The spring (not shown) embedded in the center pin 14
The center pin 14 is configured to project from above the sheet mounting surface 13a when no force is applied from the outside. The diameter of the center pin 14 is configured to be substantially equal to the diameter of the through hole 2c in the sheet 4 described above. The sheet 4 can be placed on the sheet placing surface 13 a of the flat stage 13 by fitting the through hole 2 c with the center pin 14.

Further, on the upper part of the center pin 14,
A column-shaped substrate positioning pin 15 is provided, and the center pin 14 and the substrate positioning pin 15 constitute a two-stage column-cultivated disk substrate holding unit. The diameter of the board positioning pin 15 is configured to be substantially equal to the diameter of the center hole 1b of the disk board 1. Then, while aligning the center of the disk substrate 1,
The disk substrate 1 is configured to be supported by a center pin 14. Planar stage 13 configured as above
, The sheet 4 is fitted on the center pin 14 so as to be placed thereon, and the disc substrate 1 is fitted on the board positioning pin 15 and supported by the stepped portion of the center pin 14. Then, when the sheet 4 is placed on the sheet placing surface 13a by the board positioning pins 15 and the disc substrate 1 is fitted to the board positioning pins 15, the disc substrate 1 and the sheet 4 Is configured to be able to maintain a predetermined clearance.

When the bell jar 12 is pressed against the surface of the base plate 11 on the flat stage 13 side, the bell jar 1
An O-ring 12a for sealing a space formed by the base 2 and the base plate 11 is provided.

The bell jar 12 is provided with an elastic film 16 so as to form two spaces, an open space portion and a closed space portion. The elastic film 16 has, for example, a flat disk shape having substantially uniform elastic force on the entire surface, and its outer periphery is fixed to the elastic film holding portion 12b. The elastic film 16 is formed such that the center of the plane disk shape is the center pin 14 and the substrate positioning pin 15.
Is provided so as to overlap a central axis perpendicular to a cross section parallel to the sheet mounting surface 13a. Further, as a material of the elastic film 16, for example, an elastic material which can seal a vacuum and can expand and contract, such as silicone rubber or nitrile rubber (acrylonitrile-butadiene rubber, NBR), can be used. Then, the bell jar 1 is formed by the elastic film 16.
The space inside 2 is divided into a main chamber 17 and a sub-chamber 18.

The main chamber 17 contains the bell jar 12
, A space surrounded by the elastic film 16, the elastic film holding portion 12 b, and the base plate 11. The main chamber 17 is configured to be evacuated and open to the atmosphere. The flat stage 13 having the center pin 14 and the substrate positioning pin 15 can be stored inside the main chamber 17.
Then, the disk substrate 1 and the sheet 4 are bonded in the main chamber 17. Also,
A pipe 19 communicates with a side wall of the bell jar 12 in the main chamber 17. The pipe 19 is branched at a branch part in the middle thereof, and one end thereof is connected to a branch pipe 20 which can be opened.

The sub-chamber 18 comprises a space surrounded by the upper surface and side walls of the bell jar 12, the elastic film 16, and the elastic film holding portion 12b. The sub-chamber 18 is configured to be evacuated and open to the atmosphere. The sub-chamber 18 is for expanding and contracting the elastic film 16 by evacuating and opening the inside thereof to the atmosphere. Also, the sub-chamber 18
The pipe 21 is communicated with the side wall of the bell jar 12 in FIG. The pipe 21 is connected to a branch pipe 22 whose one end can be opened at a branch part in the middle.

The pipe 21 is connected to a vacuum pump 23. Further, the pipe 21 is connected to the pipe 19 at a branch part in the middle. Thereby, the pipe 19 is configured to be connectable to the vacuum pump 23 through the pipe 21.

The pipes 19 and 21 and the branch pipes 20 and 22 are provided with valves. That is, in the pipe 19, the valve 24 is provided on the vacuum pump 23 side from the branch portion, and the valve 25 is provided in the middle of the branch pipe 20 branched from the pipe 19. In the pipe 21, a valve 26 is provided on the bell jar 12 side of the branch from the pipe 19, and a branch between the pipe 21 and the branch pipe 22, and a branch between the pipe 19 and the pipe 21. A valve 27 is provided on the vacuum pump 23 side of the section. A valve 28 is provided in the branch pipe 22. Each of these valves 24 to 28 is configured to be openable and closable, and configured to be able to open and close as needed.

As described above, the bonding apparatus 10 for bonding the disk substrate 1 and the sheet 4 according to the first embodiment
Is configured.

Then, in the preparation step in step ST3 shown in FIG. 4, first, the valve 24 shown in FIG.
28 is closed and valves 26 and 27 are opened. Further, the vacuum pump 23 is operated to evacuate the sub-chamber 18. As a result, the elastic film 16 is
8, the sub-chamber 18 has a concave shape. At this time, the base plate 11 and the bell jar 12 may be separated from each other or may be sealed. By evacuating the sub-chamber 18, the disc substrate 1 comes into contact with the elastic film 16 when the base plate 11 on which the sheet 4 and the disc substrate 1 described later are placed is closed by the bell jar 12. Can be prevented.

Next, the base plate 11 and the bell jar 1
Then, the sheet 4 is moved to a position where the flat stage 13 in the bonding apparatus 10 can be placed. Next, the sheet 4 is placed on the sheet placing surface 13a of the flat stage 13. At this time, sheet 4
Is mounted on the sheet mounting surface 13a such that the through hole 2c is fitted to the center pin 14, and the adhesive layer 2b is exposed on the upper surface. That is, when the sheet 4 is made up of the light transmissive sheet 2a and the adhesive layer 2b like the sheet 4 in the first embodiment, the sheet 4 is arranged such that the light transmissive sheet 2a is in contact with the sheet mounting surface 13a. Place. Note that the sheet 4 is made of the light-transmitting sheet 2a.
And a protective film laminated on the adhesive layer 2b and the light transmitting sheet 2a side, the sheet 4
Is placed such that this protective film is in contact with the sheet placing surface 13a.

Next, the disk substrate 1 is transported to a position above the flat stage 13 of the base plate 11. At this time, the base plate 11 may be moved. Then, the center hole 1b of the disc substrate 1 is fitted to the board positioning pin 15 so that one main surface of the disc substrate 1 on which the information signal portion 1c is provided faces the sheet 4. As a result, the inner peripheral portion (around the center hole 1b) of the disk substrate 1 is mounted on the disk substrate mounting surface 14a of the center pin 14.

As described above, each sheet 4 and disk substrate 1 are placed so that one main surface of the disk substrate 1 on which the information signal portion 1c is provided and the adhesive layer 2b of the sheet 4 face each other. The preparation process ends. afterwards,
The bell jar 12 is put on the base plate 11 so as to cover the flat stage 13 and the sheet 4 and the disk substrate 1 placed thereon. At this time, the inside of the bell jar 12 is sealed by bringing the O-ring 12a into close contact with the upper surface of the base plate 11. As a result, the closed main chamber 17 is formed. Thereafter, the process proceeds to step ST4.

In step ST4, the disk substrate 1 and the sheet 4 are bonded using the bonding device 10. FIG. 7 shows a bonding apparatus 10 corresponding to this bonding process.

That is, first, the evacuation of the sub-chamber 18 is terminated by closing the valve 26. Next, after closing the valve 25, the valve 24 is opened, and the vacuum pump 23 is operated. Thus, the inside of the main chamber 17 is evacuated. In this evacuation, evacuation is performed until the pressure inside the main chamber 17 becomes equal to the pressure inside the sub-chamber 18. Thereby, the pressure in the sub-chamber 18 and the pressure in the main chamber 17 are balanced in the elastic film 16, and the elastic film 16 becomes a flat disk shape (see FIG. 7A). Then, as shown in FIG. 5, when the elastic film 16 becomes flat, the valves 24 and 27 are closed, and the evacuation of the main chamber 17 is completed. The distance d between the flat elastic film 16 and the pressing surface (the surface opposite to the surface on which the information signal portion 1c is formed) of the disk substrate 1 fitted to the substrate positioning pins 15 is 5 to 5. The distance is set to be in a range of 70 mm, and specifically, for example, is configured to be about 10 mm.

Next, the valves 28 and 26 are opened sequentially or simultaneously. Thereby, the inside of the sub-chamber 18 is opened to the atmosphere. At this time, the pressure inside the main chamber 17 is reduced. Therefore, a pressure difference is generated between the sub-chamber 18 in which the internal pressure is at the atmospheric pressure and the main chamber 17 in which the internal pressure is reduced. Thereby, as shown in FIG. 6 and FIG.
Expands into the main chamber 17 side. here,
When the pressure inside the main chamber 17 and the pressure inside the sub-chamber 18 are equal, the elastic film 16 has a flat disk shape. Are uniformly applied to the entire surface of the disk substrate 1, and the elastic film 16 expands in a rotationally symmetric shape with respect to the central axis of the disk substrate 1. This elastic film 1
Due to the expansion of 6, the other main surface of the disk substrate 1 is pressed.
Here, the pressing force is a force obtained by subtracting the restoring force (opposite direction) of the elastic film 16 from the differential pressure between the pressure (atmospheric pressure) in the sub-chamber 18 and the pressure (vacuum) in the main chamber 17. is there. In the first embodiment, the pressure in the main chamber 17 is increased from 4.0 × 10 ^{2 to} 2.0 ×
By reducing the pressure to 10 ⁴ Pa, the pressure difference between this pressure and the atmospheric pressure (81325 to 100925 Pa) is increased.
6, a force obtained by subtracting the restoring force of the elastic film 16 from the differential pressure, specifically, 71325 to 90925 Pa, is set so as to be a pressing force for pressing the other main surface of the disk substrate 1. Here, in the first embodiment, the pressing force is specifically about 8.0 × 10 ⁴ Pa, for example.

Due to the expansion of the elastic film 16, the other main surface of the disk substrate 1 is instantaneously spread from the periphery of the center hole 1 b toward the outer periphery and is pressed over the entire surface.
At this time, the sub chamber 18 and the main chamber 17
Pressure acts uniformly on the entire surface of the elastic film 16, and further, the elastic film 16 reduces the pressing force of the disk substrate 1.
Acts uniformly on the entire surface of the other main surface.

Then, the substrate positioning pins 15 are pressed by the elastic film 16, and the center pins 14 are pressed via the disk substrate 1, and are pushed into the interior of the flat stage 13. Along with this, one main surface of the disk substrate 1 is sequentially pressed and bonded to the adhesive layer 2b of the sheet 4 from the periphery of the center hole 1b to the outer peripheral portion. In this bonding, since the inside of the main chamber 17 is evacuated to a vacuum, no air bubbles enter between the disk substrate 1 and the sheet 4, thereby preventing air bubble unevenness.

At this stage, the portion of the elastic film 16 pressing the disk substrate 1 becomes substantially flat along the shape of the disk substrate 1, and the disk substrate 1 and the sheet 4 are bonded together. The pressed state is obtained. Then, this crimped state is set in a range from 1 s to less than 60 s, preferably 1 s to 60 s.
During the period from s to 40 s, in the first embodiment, it is maintained for, for example, 5 s. Thereby, pressure bonding between the disk substrate 1 and the sheet 4 is stabilized.

After the crimping is stabilized, the inside of the main chamber 17 is opened to the atmosphere by opening the valve 25. Thereby, both the inside of the main chamber 17 and the inside of the sub-chamber 18 become the atmospheric pressure. Along with this, as shown in FIG. 7C, the elastic film 16 is restored to a flat disk shape along the elastic film holding portion 12b, and the center pin pressed into the inside of the flat stage 13 is formed. 14 is restored, and returns to the state when the disk substrate 1 was fitted.

After the opening of the inside of the main chamber 17 to the atmosphere is completed, the bell jar 12 is separated from the base plate 11. Thereafter, the disk substrate 1 on which the sheet 4 is bonded on one main surface is transferred to a predetermined transport device (not shown).
Remove using In a state where the base plate 11 and the bell jar 12 are separated from each other, the sheet 4 and the disk substrate 1 on which the next bonding is to be performed are newly placed at the above-described predetermined positions. In parallel with this,
The valve 28 shown in FIG. 5 is closed and the valve 27 is opened, and the inside of the sub-chamber 18 is evacuated by the vacuum pump 23. As shown in FIG.
8 is concave.

As described above, the replica substrate 1 shown in FIG.
The information signal portion 1c and the light transmitting layer 2 composed of the adhesive layer 2b and the light transmitting sheet 2a are formed on one main surface on which the irregularities a are formed.
The optical disk provided with the above is manufactured.

Here, the present inventor has determined the process tact time when an optical disk was manufactured using the bonding apparatus according to the first embodiment and the optical disk using the conventional bonding apparatus (see FIG. 15). The process tact time in the case of manufacturing was compared. In this comparison, the inner volume of the bell jar in the conventional laminating apparatus is made equal to the inner volume of the bell jar 12 of the laminating apparatus according to the first embodiment. Further, the inner volume of the subchamber 18 is set to １ ／ of the inner volume of the bell jar 12.
And the pressure in the main chamber 17 during evacuation,
The pressure inside the bell jar (in the closed chamber) at the time of vacuuming in the conventional bonding apparatus is set to the same pressure. The same base plate is used. The results are shown in Table 1 below.

[0090]

[Table 1]

In the process using the conventional bonding apparatus shown in Table 1, first, after separating the base plate and the bell jar, the sheet and the disk substrate are placed at predetermined positions on the flat stage on the base plate. I do. After that, the base plate and the bell jar are covered so as to cover the flat stage to form a chamber. Thereafter, the inside of the chamber is evacuated. Here, it takes 10 seconds to reduce the pressure to a predetermined pressure (for example, 4.0 × 10 ³ Pa). On the other hand, in the main chamber 17 having a half volume of the bell jar 12, the time required to reduce the pressure to the above-described predetermined pressure is 5 seconds. That is, in the conventional laminating apparatus, when the time for evacuating to a predetermined pressure is 10 seconds, the main chamber 1 having a half volume thereof
In 7, the pressure can be reduced to a predetermined pressure in a half of 5 seconds. Further, in the conventional laminating apparatus, when the sheet and the disk substrate are placed on the flat stage, the chamber cannot be evacuated at the same time. The evacuation in the chamber 18 and the placement of the sheet 4 and the disk substrate 1 can be performed in parallel.

Next, the press time (pressure bonding time) is the same in both the conventional bonding apparatus and the bonding apparatus according to the fifth embodiment, for example, 5 seconds.

Next, the disk substrate 1 on which the sheet 4 is bonded is placed on the flat stage 13 on the base plate 11.
It is necessary to open the inside of the main chamber 17 to the atmosphere in order to carry it out. Similarly, in the conventional laminating apparatus, it is necessary to open the inside of the chamber to the atmosphere in order to carry out the disk substrate on which the sheets are laminated from the flat stage of the base plate. When the time required for opening to the atmosphere is 10 seconds in the conventional bonding apparatus, the main chamber 17 having a half volume thereof can be opened to the atmosphere in half 5 seconds.

Thereafter, in the conventional laminating apparatus and the laminating apparatus according to the first embodiment, the bell jar and the base plate are separated, and the disk substrate on which lamination is completed is carried out. Thereafter, the sheet and the disk substrate are sequentially placed on a predetermined position of the base plate on the flat stage, and the substrate is replaced. This substrate exchange is the same process in the case where the conventional bonding apparatus is used and in the case where the bonding apparatus 10 according to the first embodiment is used. The time required for the substrate replacement is, for example, about 5 seconds.

In the above-described bonding process, the time (process tact time) required from the substrate replacement to the next substrate replacement is 30 seconds in the conventional bonding apparatus, whereas the time required for the conventional bonding apparatus is 30 seconds. In the bonding apparatus, the time is 20 seconds, which indicates that the process tact time can be reduced. In these bonding apparatuses, even when vacuum pumps having the same pumping capacity are used, the volume and time required for vacuum pumping can be reduced by the conventional bonding apparatus according to the first embodiment. / 2. Therefore, the time for evacuation of the main chamber and opening to the atmosphere can be significantly reduced. Further, by further reducing the internal volume of the main chamber 17,
The time for evacuation of the main chamber 17 and opening to the atmosphere can be further reduced.

In the conventional bonding apparatus,
It is necessary to provide a pad made of an elastic body having a conical shape and a radius of curvature of about 100 mm for pressing the disk substrate inside the chamber. Therefore, while the internal volume of the bell jar could not be reduced, the bonding apparatus according to the first embodiment utilizes the difference between the pressure in the sub-chamber 18 and the pressure in the main chamber 17. Thus, a pressing force is applied to the disk substrate 1 via the elastic film 16 to bond the disk substrate 1 and the sheet 4 together. Therefore, in the bonding apparatus 10 according to the first embodiment, since it is not necessary to use a conical pad or the like, the inner volume of the bell jar 12 can be reduced. Thereby, the inner volume of the bell jar 12 can be reduced, and the sub-chamber 18 and the main chamber 17 can be reduced to further reduce their internal volumes, so that the space for the bonding apparatus can be saved. In addition, by reducing the inner volumes of the main chamber 17 and the sub-chamber 18, the time for evacuation and opening to the atmosphere can be reduced.
Therefore, the process tact time can be further reduced, and the manufacturing tact can be increased, so that the manufacturing efficiency of the optical disc can be improved.

Further, since there is no need to use a conventional pad or the like for pressing the disk substrate 1, there is no need to provide a pressing mechanism such as an air cylinder for pressing the pad against the disk substrate. Therefore, in the bonding apparatus, further space saving can be achieved.

As described above, according to the first embodiment, the bell jar 12 is divided into the main chamber 17 and the sub-chamber 18 by the elastic film 16 so that the main chamber 17 and the sub-chamber 18 are separated. The light transmission layer 2 is formed by laminating the sheet 4 on one main surface of the disk substrate 1 on which the information signal portion 1c is provided by utilizing a pressure difference with the disk substrate 1. Since the pressing force can be uniformly applied to the entire surface of the other main surface of the disk substrate 1, a change in the skew of the disk substrate 1 can be suppressed to a minimum. Also, the elastic film 1
Since the inside of the main chamber 17 is evacuated to expand the inside of the main chamber 17, air bubbles can be prevented from being mixed between the disk substrate 1 and the sheet 4. The prevention effect can be improved, and the light transmitting layer 2 having a small thickness unevenness can be formed. Therefore, it has a thin, thin, small birefringent, light-transmitting layer with good transparency and uniform thickness, and high reliability that can support high NA of the objective lens. An optical disk having the same can be manufactured.

Next, a description will be given of a bonding apparatus according to a second embodiment of the present invention and a method of manufacturing an optical disk using the bonding apparatus. The optical disk, the disk substrate 1 and the sheet 4 according to the second embodiment are the same as in the first embodiment, and a description thereof will be omitted.

Hereinafter, a bonding apparatus according to the second embodiment will be described. FIG. 8 shows a bonding apparatus according to the second embodiment.

As shown in FIG. 8, in the bonding apparatus according to the second embodiment, unlike in the first embodiment, a branch pipe 31 branched from the pipe 21 is added to a branch pipe further branched in the middle thereof. 32 are provided. A pressurizing device 33 is connected to the branch pipe 31 so that at least the inside of the sub-chamber 18 can be pressurized through the branch pipe 31 and the pipe 21. A valve 28 similar to that of the first embodiment is provided on a side of the branch pipe 31 closer to the bell jar 12 than a branch portion of the branch pipe 32 with the branch pipe 32. A valve 34 that can be freely opened and closed is provided in the middle of the branch pipe 32. For other configurations of the bonding device,
The description is omitted because it is the same as in the first embodiment.

Next, the step of bonding the disk substrate 1 and the sheet 4 according to the second embodiment will be described.

First, the vacuum pump 23 is operated, the valves 24 and 28 are closed, and the valves 26 and 27 are opened. As a result, the inside of the sub-chamber 18 is evacuated. Then, the elastic film 16 is drawn into the sub-chamber 18, and the sub-chamber 18 becomes concave. In addition,
At this time, the base plate 11 and the bell jar 12 may be separated from each other or may be sealed.

After the base plate 11 and the bell jar 12 are separated from each other, the sheet 4 is moved to a position where the flat stage 13 can be placed on the bonding apparatus 10. Thereafter, the sheet 4 is placed on the sheet placing surface 13a of the flat stage 13. At this time, the sheet 4 is placed on the sheet placing surface 13a such that the through-hole 2c is fitted to the center pin 14, and the adhesive layer 2b faces upward. Here, when the sheet 4 is composed of the light transmissive sheet 2a and the adhesive layer 2b, the sheet 4
Is placed so that the light transmissive sheet 2a is in contact with the sheet placing surface 13a. Further, the sheet 4 is replaced with the light transmissive sheet 2a.
And a protective film laminated on the adhesive layer 2b and the light transmitting sheet 2a side, the protective film is placed so as to be in contact with the sheet placing surface 13a.

Next, the disk substrate 1 is transported to a position above the flat stage 13 of the base plate 11. In addition,
At this time, the base plate 11 may be moved. Then, the center hole 1b of the disc substrate 1 is fitted to the board positioning pin 15 so that one main surface side on which the information signal portion 1c is provided faces the sheet 4. Thus, the inner peripheral portion (near the center hole 1b) of the disk substrate 1 is mounted on the outer peripheral portion of the center pin 14.

As described above, each sheet 4 and disk substrate 1 are placed such that one main surface of the disk substrate 1 on which the information signal portion 1c is provided and the adhesive layer 2b of the sheet 4 face each other. The preparation process ends. afterwards,
The bell jar 12 is pressed onto the base plate 11 so as to cover the flat stage 13 and the sheet 4 and the disk substrate 1 placed thereon. At this time,
The inside of the bell jar 12 is sealed by bringing the ring 12 a into close contact with the upper surface of the base plate 11.
As a result, the closed main chamber 17 is formed. Thereafter, the process proceeds to step ST4.

In step ST4, the disk substrate 1 and the sheet 4 are bonded using the bonding device 10.

That is, first, the valve 26 is closed to terminate the evacuation of the sub-chamber 18. Next, after closing the valve 25, the valve 24 is opened, and the inside of the main chamber 17 is evacuated by the operating vacuum pump 23. In this evacuation, evacuation is performed until the pressure inside the main chamber 17 becomes equal to the pressure inside the sub-chamber 18. Thereby, the pressure in the sub-chamber 18 and the pressure in the main chamber 17 are balanced in the elastic film 16, and the elastic film 16 becomes a flat disk shape. When the elastic film 16 has become a flat disk, the valves 24 and 27 are closed, and the evacuation of the main chamber 17 is completed. The distance d between the flat elastic film 16 and the pressing surface (the surface opposite to the surface on which the information signal portion 1c is formed) of the disk substrate 1 fitted to the substrate positioning pins 15 is 5 to 5. The distance is set to be in a range of 70 mm, and specifically, for example, is configured to be about 10 mm.

Next, the valves 28, 26 and 34 are opened sequentially or simultaneously. Thereby, the sub-chamber 18
Open the inside of the to the atmosphere. At this time, the main chamber 1
Since the inside of the chamber 7 is evacuated and reduced in pressure, a pressure difference is generated between the sub-chamber 18 in which the internal pressure is atmospheric pressure and the main chamber 17 in which the pressure is reduced. As a result, the elastic film 16 expands inside the main chamber 17. The other main surface of the disk substrate 1 is pressed by the expansion of the elastic film 16. Immediately thereafter, the valve 34 is closed, and on the other hand, the pressurizing device 33 is operated to pressurize the inside of the sub-chamber 18 through the branch pipe 31 and the pipe 21. Then, the pressure inside the sub-chamber 18 is set to a pressure higher than the atmospheric pressure. Thus, the pressing force applied to the other main surface of the disk substrate 1 via the elastic film 16 is the pressure in the sub-chamber 18 (higher than the atmospheric pressure) and the pressure in the main chamber 17 (vacuum).
And the pressure difference. That is, the pressing force is obtained from the differential pressure between the pressure in the sub-chamber 18 (higher than the atmospheric pressure) and the pressure in the main chamber 17 (vacuum).
This is a force obtained by subtracting the restoring force (opposite direction) of No. 6. In the second embodiment, the pressure in the main chamber 17 is reduced from 4.0 × 10 ^{2 to} 2.0 × 10 ⁴ Pa by evacuation.
And the pressure in the sub-chamber 18 is reduced from 151988 to 506625.
It is pressurized so as to have a pressure selected from the range of Pa (1.5 to 5.0 atm). As a result, a pressure difference (131988 to 506225 Pa) between the pressure in the main chamber 17 and the pressure in the sub-chamber 18 acts on the elastic film 16. Then, a force obtained by subtracting the restoring force of the elastic film 16 from the differential pressure becomes a pressing force for pressing the other main surface of the disk substrate 1.

Due to the above-mentioned pressure difference, the elastic film 16
Is instantaneously expanded and spread from the periphery of the center hole 1b to the outer periphery on the other main surface of the disk substrate 1, whereby the entire surface is pressed. At this time, sub chamber 1
The pressure in 8 acts uniformly on the entire surface of the elastic film 16, and the pressing force of the elastic film 16 uniformly acts on the entire other main surface of the disk substrate 1. Here, in the second embodiment, the pressing force acting on the other main surface of the disk substrate 1 is 12
The vacuum pump 23 and the pressurizing device 33 are controlled so as to be in the range of 1988 to 496225 Pa. In the second embodiment, the pressing force is specifically, for example, 2.5 ×
10 ⁵ Pa.

Then, the substrate positioning pins 15 are pressed by the expansion of the elastic film 16 and the disk substrate 1 is pressed.
The center pin 14 is pressed through the
3 is pushed inside. Accordingly, the disk substrate 1
One main surface is sequentially pressure-bonded to the pressure-sensitive adhesive layer 2b of the sheet 4 from the periphery of the center hole 1b to the outer peripheral portion, and bonded to each other. In this bonding, the inside of the main chamber 17 is evacuated. Therefore, air bubbles do not enter between the disk substrate 1 and the sheet 4, and unevenness of the air bubbles can be prevented.

In this bonded stage, the portion of the elastic film 16 that presses the disk substrate 1 becomes substantially flat along the shape of the disk substrate 1, and the disk substrate 1 and the sheet 4 are bonded together. The crimped state is adjusted. Then, in the second embodiment, the press-bonded state is held for a period of, for example, 5 seconds to 40 seconds, preferably 1 second to 60 seconds, for example, for 5 seconds. Thereby, pressure bonding between the disk substrate 1 and the sheet 4 is stabilized.

After the pressure is stabilized, the interior of the sub-chamber 18 is returned to the atmospheric pressure by opening the valve 34, and then the interior of the main chamber 17 is opened to the atmosphere by opening the valve 25. As a result, the interior of the main chamber 17 and the interior of the sub-chamber 18 are both at atmospheric pressure, the elastic film 16 is restored, and becomes a flat disk along the elastic film holding portion 12b. The pushed center pin 14 is restored, and returns to the state when the disc substrate 1 is fitted. Simultaneously with or after the main chamber 17 is opened to the atmosphere, the valve 28 is closed and the valve 27 is opened.
Start evacuating the inside of the.

After the opening of the inside of the main chamber 17 to the atmosphere is completed, the bell jar 12 is separated from the base plate 11. Thereafter, the disk substrate 1 on which the sheet 4 is bonded on one main surface is transferred to a predetermined transport device (not shown).
Remove using In a state where the base plate 11 and the bell jar 12 are separated from each other, the sheet 4 and the disk substrate 1 on which the next bonding is to be performed are newly placed at the above-described predetermined positions.

As described above, an optical disc having the information signal portion 1c and the light transmitting layer 2 composed of the adhesive layer 2b and the light transmitting sheet 2a provided on one of the main surfaces of the replica substrate 1a having the unevenness is manufactured. You.

According to the second embodiment, the bell jar 12 is divided into two chambers, the main chamber 17 and the sub-chamber 18, and the pressure difference between the main chamber 17 and the sub-chamber 18 is used. The same effect as in the first embodiment can be obtained by forming the light transmitting layer 2 by bonding the sheet 4 on one main surface on which the information signal portion 1c is provided. At the same time, the disk substrate 1 is
When the inside of the sub-chamber 18 is pressurized to be higher than the atmospheric pressure at the time of bonding, the pressing force between the disk substrate 1 and the sheet 4 can be further increased. 4 can be bonded more reliably. When the pressure difference between the atmospheric pressure and the vacuum is used, the disk substrate 1
Although only a pressing force smaller than the atmospheric pressure acts at the maximum, the elastic film 16 is expanded by the pressing force larger than the atmospheric pressure by pressurizing the inside of the sub-chamber 18, and the disk substrate 1 is further moved through the elastic film 16. Since the pressing is performed, the change in the skew in the disk substrate 1 can be further improved.

Next, a bonding apparatus according to a third embodiment of the present invention will be described. FIG. 9 shows a bonding apparatus according to the third embodiment. The disc substrate 1, sheet 4, and optical disc used for bonding according to the third embodiment are the same as those in the first embodiment, and thus description thereof will be omitted.

As shown in FIG. 9, in the bonding apparatus according to the third embodiment, unlike the second embodiment, the elastic film 16 is formed of an elastic material having a low elastic modulus on the inner peripheral portion. A high elastic film 16b made of an elastic material having a higher elastic modulus than the inner peripheral portion on the outer periphery using the low elastic film 16a
Is used. Specifically, the diameter when the elastic film 16 is a flat disk is set to 130 to 180 mm, and is set to, for example, 140 mm in the third embodiment. When the elastic film 16 has a flat disk shape, the low elastic film 16a
Has a diameter of 110 to 130 mm, and is preferably substantially equal to the diameter of the disk substrate 1, for example, 120 mm. Further, on the outer periphery of the low elastic film 16a, a high elastic film 16b having a flat annular shape is provided.

The other configuration and the bonding method of the bonding apparatus according to the third embodiment are the same as those in the second embodiment, and thus the description is omitted.

In the bonding apparatus according to the third embodiment, since the configuration other than the elastic film 16 is the same as that of the second embodiment, the same effect as that of the second embodiment can be obtained. When the sub-chamber 18 is opened to the atmosphere, the low elasticity film 16a expands from the center thereof, and can be pressed against the other main surface of the disk substrate 1 from the center to the outer periphery. When the pressure in the sub-chamber 18 is set higher than the atmospheric pressure by the pressure device 33, the pressing force can be efficiently applied to the other main surface of the disk substrate 1. Therefore, the disk substrate 1 is also bonded to the sheet 4 sequentially from the periphery of the center hole 1b toward the outer periphery, so that the effect of preventing air bubbles from entering between the disk substrate 1 and the light transmitting layer 2 can be improved. .

Next, a bonding apparatus according to a fourth embodiment of the present invention will be described. FIG. 10 shows a bonding apparatus according to the fourth embodiment. Note that this fourth
The disk substrate 1, the sheet 4, and the optical disk used for bonding according to the second embodiment are the same as those in the first embodiment, and thus description thereof will be omitted.

As shown in FIG. 10, in the bonding apparatus according to the fourth embodiment, unlike the first embodiment, the elastic film 16 is made of an elastic material having a high elastic modulus on the inner peripheral portion. A low-elastic film 16 made of an elastic material having a lower elastic modulus than the inner peripheral portion on the outer peripheral portion using the high elastic film 16c.
Use d. Specifically, the diameter when the elastic film 16 is a flat disk is set to 130 to 180 mm, and in the fourth embodiment, it is set to, for example, 140 mm.
Further, when the elastic film 16 has a flat disk shape,
The diameter of c is set to be 110 to 130 mm, and preferably approximately equal to the diameter of the disk substrate 1, for example, 120 mm. Further, a planar annular high elastic film 16d is provided on the outer periphery of the high elastic film 16c.

The other configuration and the bonding method of the bonding apparatus according to the fourth embodiment are the same as those in the first embodiment, and thus the description is omitted.

In the bonding apparatus according to the fourth embodiment, since the configuration other than the elastic film 16 is the same as that of the first embodiment, the same effect as that of the first embodiment can be obtained. In addition, a high elastic film 16c made of an elastic material having a high elastic modulus is used as the elastic film 16 on the inner peripheral portion, and a low elastic material made of an elastic material having a lower elastic modulus than the inner peripheral portion is used on the outer peripheral portion. By using the body film 16d, when the sub-chamber 18 is opened to the atmosphere,
The low elastic film 16a is moved from the center to the main chamber 17
Since it extends inward and can be pressed against the other main surface of the disk substrate 1 from the center to the outer peripheral portion, the pressing force can be efficiently applied to the other main surface of the disk substrate 1. Therefore, the disk substrate 1 is also bonded to the sheet 4 sequentially from the periphery of the center hole 1b toward the outer periphery, so that the effect of preventing air bubbles from entering between the disk substrate 1 and the light transmitting layer 2 can be improved. .

Next, a description will be given of a bonding apparatus according to a fifth embodiment of the present invention. FIG. 11 shows a bonding apparatus 10 according to the fifth embodiment. Note that the disk substrate 1, sheet 4, and optical disk used for bonding according to the fifth embodiment are the same as those in the first embodiment, and a description thereof will be omitted.

As shown in FIG. 11, the flat stage 40 of the bonding apparatus according to the fifth embodiment includes a sheet 4
And the sheet 4 can be placed thereon. A plurality of vacuum suction holes (not shown) are provided on the sheet mounting surface 40a of the flat stage 40. These vacuum suction holes are configured so that the inside thereof can be evacuated. Thereby, the sheet 4 can be suction-fixed on the sheet mounting surface 40a while maintaining flatness.

The plane stage 40 is provided with a center pin 14 which is movable in a direction in which the plane pin 40 projects and buries with respect to the sheet mounting surface 40a. The diameter of the center pin 14 is configured to be substantially equal to the diameter of the through hole 2c of the sheet 4 described above. The sheet 4 can be placed on the sheet placing surface 40a by fitting the through hole 2c to the center pin 14. The plane stage 40 is provided with a space in which the center pin 14 can be stored. In this space, a coil spring (not shown) configured to project the center pin 14 is provided so as to be connected to a lower portion of the center pin 14. Then, by pushing the center pin 14 in a direction perpendicular to the sheet placing surface 40a,
The center pin 14 is configured to be buried in the plane stage 40.

Further, on the upper part of the center pin 14,
A substrate positioning pin 15 protruding in a cylindrical shape is provided. The diameter of the substrate positioning pin 15 is configured to be substantially equal to the diameter of the center hole 1b of the disk substrate 1 described above. When the center hole 1b of the disk substrate 1 is fitted to the substrate positioning pin 15, the inner peripheral portion of the disk substrate 1, that is, the periphery of the center hole 1b can be supported by the disk substrate mounting surface 14a. ing. That is, the center pin 14
And the substrate positioning pin 15, the sheet mounting surface 40 a
Is formed in a two-stage cylindrical shape having a concentric circle in cross section, so that the center position between the disk substrate 1 and the sheet 4 can be set.

Further, on the outer peripheral side of the sheet placing surface 40a,
A disk outer peripheral support portion 41 which can support the outer peripheral portion of the disk substrate 1 and includes a plurality of pins arranged on a concentric circle is provided. This disk outer periphery support portion 41
Is for forming a clearance between the disk substrate 1 and the sheet 4. In particular, the disk outer peripheral supporting portion 41 is configured to be able to support by lifting the outer peripheral portion of the disk substrate 1, and the upper end surface supporting the disk substrate 1 is substantially parallel to the sheet mounting surface 40a. It is provided as follows.

The disk outer peripheral support portion 41 is provided so as to be able to protrude and be buried in a direction inclined with respect to the sheet mounting surface 40a toward the direction in which the center pin 14 is provided. That is, a space in which the disk outer peripheral support portion 41 can be embedded is formed on the sheet mounting surface 40a.
In this space, a coil spring 42 is provided so as to be connected to a lower portion of the disk outer peripheral support portion 41. Thus, the disk outer peripheral support portion 41 can be maintained in a state where it protrudes above the sheet mounting surface 40a in a normal state. On the other hand, when the disk outer peripheral support portion 41 is pressed in the direction opposite to the direction in which it protrudes, the disk outer peripheral support portion 41 can be buried in the sheet mounting surface 40a. That is, the direction in which the disk outer peripheral supporting portion 41 is inclined toward the central portion of the center pin 14 with respect to the sheet mounting surface 40a by the coil spring 42 (see FIG. 11).
It is configured so that it can be buried / projected in the middle and arrow a). The spring constant of the coil spring 42 is preferably 1.0 N /
Although m is not necessarily limited to this value, an appropriate value is used depending on the number of pins and the pressing force described later. Also, instead of the coil spring 42,
It is also possible to use other elastic means having a similar elasticity.

Further, a space 43 is provided in the plane stage 40. Inside the space 43, there is provided an outer peripheral support moving mechanism 44 which is configured to be movable in a direction substantially parallel to the laminating direction of the disk substrates 1 (the direction of arrow b in FIG. 11). A coil spring 42 is connected to the outer peripheral portion of the outer peripheral support moving mechanism 44. Here, the coil spring 42 is connected to the other end opposite to the one end connected to the disk outer peripheral support 41. Then, when the disk outer peripheral supporting portion 41 is buried in the flat stage 40 without applying a force from above, the outer peripheral supporting portion moving mechanism 44 is moved in a direction in which an attractive force is generated in the coil spring 42 (in FIG. 11, below arrow b). Move to As a result, a tensile force is generated in the coil spring 42, and the disk outer peripheral supporting portion 41 is pulled and can be buried in the flat stage 40. In this manner, the upper end of the disk outer peripheral supporting portion 41 can be drawn into the flat stage 40. Further, if necessary, the upper end of the disk outer peripheral support portion 41 can be made flush with the sheet mounting surface 40a.

Further, as described above, the disk outer periphery support portion 41 is composed of a plurality of pins. Here, FIG. 12 shows a plan view of the sheet mounting surface 40a provided with the disk outer peripheral supporting portion 41. As shown in FIG. 12, the plurality of pins constituting the disk outer periphery supporting portion 41 have a top surface having, for example, a circular or elliptical shape and a virtual radius r ₁ centered on the center of the center pin 14. It is provided on the circumference. Further, the radius r ₁ of a virtual circle in which a plurality of pins constituting the disk outer periphery supporting portion 41 are arranged is at least the radius r _{0 of the} sheet 4 (for example, r ₀
= 60 mm). In addition, the disk outer peripheral support 4
The individual pins in 1 are preferably provided at the vertices of a regular polygon (regular n-gon) inscribed in the circle. Here, in the fifth embodiment, the plurality of pins are
The center is provided at each vertex of a regular octagon inscribed in a virtual circle having a radius r ₁ = 61 mm.

FIG. 13 shows an enlarged view of a pin constituting the disk outer periphery supporting portion 41. As shown in FIG. As shown in FIG. 13, the diameter or the major diameter (R) of a circle or an ellipse at the upper end of each of the pins constituting the disk outer periphery supporting portion 41 is, for example, 1.0 mm. The height h of the upper end of the disk outer peripheral supporting portion 41 from the sheet mounting surface 40a when the disk outer peripheral supporting portion 41 protrudes in a state where the disk substrate 1 is mounted is in a range of 1.0 mm or more. ,
Preferably, it is selected from a range of 1.0 to 5.0 mm, and in the fifth embodiment, for example, h is set to 2.0 mm. Further, the width Δr of the region for supporting the disk substrate 1 at the upper end of the disk outer peripheral support portion 41 is 0.3 mm
It is selected to be equal to or less than the diameter or the major diameter R of the pin. In the fifth embodiment, Δr is 0.3 to
1.0 mm, specifically, for example, Δr =
0.5 mm is selected. The area of the disk substrate 1 supported by the disk outer peripheral supporting portion 41 is a region Δr from the outer periphery of the disk substrate 1, and the disk outer peripheral supporting portion 41 of the belt-shaped region outside the circle having the radius r _2.
Of the upper end of the In addition, the disk outer periphery support portion 41
Is inclined in the direction in which the center pin 14 is installed, for example, in a direction at an angle of 63 ° (= arctan (2/1)) from the sheet mounting surface 40a. This angle of inclination is
It is determined by the required clearance between the disk substrate 1 and the sheet 4 and the width of a region for supporting the disk substrate 1 at the upper end of the disk outer peripheral support portion 41, and is not necessarily limited to this angle. However, in an inclined state, at an angle larger than 0 °,
It must be at least less than 90 ° (0 ° <θ <90 °), and in consideration of the moving direction of the disk outer peripheral supporting portion 41, that is, the direction of burying in the sheet mounting surface 40a,
Preferably, it is 50 ° to 70 ° (50 ° <θ <70 °).

As described above, the flat stage 40 of the bonding apparatus 10 is configured. The configuration of the bonding apparatus other than the plane stage 40 is the same as that in the first embodiment, and thus the description is omitted.
Further, as the flat stage 13 of the bonding apparatus 10 according to the second, third, and fourth embodiments, the flat stage 40 according to the fifth embodiment can be employed.

In the preparation step (see FIG. 4) in step ST3 according to the fifth embodiment, first, as shown in FIG. The direction in which the coil spring 42 generates a tensile force (downward in FIG. 11)
Move to Then, the disk outer peripheral support portion 41 is drawn into the flat stage 40 at least to the extent that the upper end does not hinder the placement of the sheet 4.

Next, the sheet 4 is placed on the sheet mounting surface 40 so that the through-hole 2 c is fitted to the center pin 14 while the adhesive layer 2 b side faces the elastic film 16.
a. Along with the placement of the sheet 4, the inside of a vacuum suction hole (not shown) provided in the flat stage 40 is evacuated. Thereby, the sheet 4 is moved to the sheet placing surface 4.
0a can be adsorbed while maintaining a flat shape. Generally, the sheet 4 is often wound in a roll shape at least at a stage before being punched into a flat annular shape before bonding to the disk substrate 1. Therefore, when the sheet 4 is placed on the sheet placement surface 40a, a state where the sheet 4 is wound in a roll shape appears, and a habit such as a curl appears. Therefore, by adsorbing the sheet 4 on the sheet mounting surface 40a,
The sheet 4 can be fixed in a planar shape.

Next, the outer-peripheral-portion-portion moving mechanism 44 is moved in the direction in which the coil spring 42 generates a repulsive force (upward in FIG. 11).
Move to As a result, the disk outer peripheral supporting portion 41 is pushed by the coil spring 42 and is projected to a normal height h, for example, h = 2 mm in the fifth embodiment.

Next, the disk substrate 1 is placed on the flat stage 4
Conveyed to 0. Then, the center hole 1b of the disc substrate 1 is fitted to the board positioning pin 15 so that one main surface of the disc substrate 1 on which the information signal portion 1c is provided faces the sheet 4. As a result, the inner peripheral portion (around the center hole 1b) of the disk substrate 1 is mounted on the disk substrate mounting surface 14a, and the outer peripheral portion (the portion Δr from the outer circumference of the disk substrate) is positioned on the upper end of the disk outer peripheral support portion 41 Placed on At this time, even when the disk substrate 1 is placed slightly obliquely or the disk substrate is warped, the outer peripheral portion of the disk substrate 1 is supported on the upper end of the disk outer peripheral support portion 41. A clearance is formed between the disk substrate 1 and the sheet 4 to prevent a so-called blocking phenomenon in which one main surface of the disk substrate 1 and the adhesive layer 2b of the sheet 4 come into contact with each other before bonding. it can.

As described above, each of the sheet 4 and the disk substrate 1 is placed so that one main surface of the disk substrate 1 on which the information signal portion 1c is provided and the adhesive layer 2b of the sheet 4 face each other. The preparation process ends. afterwards,
The process proceeds to step ST4.

In step ST4, the disk substrate 1 and the sheet 4 are bonded using the bonding apparatus 10 having the flat stage 40.

That is, first, similarly to the first embodiment, the pressure difference between the pressure inside the main chamber 17 and the pressure inside the sub-chamber 18 is reduced by the elastic film 16.
Then, the substrate positioning pins 15 are pressed via the elastic film 16, and the center pins 14 are pressed via the disk substrate 1, and are pushed into the plane stage 40. Accordingly, one main surface of the disk substrate 1 is sequentially adhered to the adhesive layer 2b of the sheet 4 from the periphery of the center hole 1b to the outer peripheral portion, and is adhered. Here, the pressing force applied to the other main surface of the disk substrate 1 at the time of this pressing depends on the pressure difference between the atmospheric pressure in the sub-chamber 18 and the pressure in the main chamber 17,
Further, in consideration of the restoring force of the elastic film 16, specifically, it is set to be in the range of 71325 to 90925 Pa. Here, in the fifth embodiment,
Specifically, for example, it is about 8.0 × 10 ⁴ Pa.

At this time, in the disk outer peripheral supporting portion 41 shown in FIG. 13, the disk outer peripheral supporting portion 41 is pressed through the outer peripheral portion of the disk substrate 1 by the pressing of the elastic film 16 against the disk substrate 1. You. Then, the disk outer peripheral support portion 41 is gradually pushed into the plane stage 40. In this manner, the disk outer peripheral support 4
As the clearance h decreases, the region supporting the outer peripheral portion of the disk substrate 1 at the upper end, that is, the supporting width Δr decreases, and the disk substrate 1
Moves outward from the outer periphery of the. Then, when the width Δr of the supported region in the outer peripheral portion of the disk substrate 1 becomes 0, that is, in the fifth embodiment,
The clearance h between the sheet 4 and the disk substrate 1 is almost 1
When the diameter becomes about mm, one main surface of the disk substrate 1 is bonded to the adhesive layer 2b of the sheet 4 at a stretch. At this stage, the elastic film 16 has a substantially flat plate shape along the other main surface of the disk substrate 1, and the disk substrate 1 and the sheet 4
Are bonded to each other to form a crimped state. At this time, in the fifth embodiment, the crimped state is maintained for 1 second to less than 60 seconds, preferably for 1 second to 40 seconds, for example, for 5 seconds. Thereby, pressure bonding between the disk substrate 1 and the sheet 4 is stabilized.

During the pressure bonding or after the pressure bonding is stabilized, the vacuum state in the vacuum suction hole of the flat stage 40 is released,
The sheet 4 is released from the suction fixing. Thereafter, the inside of the main chamber 17 is opened to the atmosphere as in the first embodiment. As a result, the elastic film 16 is
The disk substrate 1 is restored in the direction away from 0 to become a flat disk shape, and the restoring force of the center pin 14
And the sheet 4 is lifted from the sheet mounting surface 40a.

Then, after the bell jar 12 is separated from the base plate 11, the disk substrate 1 and the sheet 4 which have been pressure-bonded through the adhesive layer 2b are carried out from the plane stage 40 by using a predetermined transfer device (not shown). .

As described above, similar to the first embodiment, one main surface of the replica substrate 1a where the unevenness is formed,
Information signal portion 1c, adhesive layer 2b and light transmissive sheet 2
An optical disk provided with the light transmission layer 2 made of a is manufactured.

As described above, according to the fifth embodiment, in the manufacture of an optical disk in which the sheet 4 is bonded to the sheet 4 by pressing the disk substrate 1 on the sheet 4, By pressing the other main surface of the substrate 1 in the same manner as in the first embodiment, the same effect as in the first embodiment can be obtained, and the outer peripheral portion of the disk substrate 1 , Supported by a disk outer peripheral support portion 41 composed of a plurality of pins inclined toward the center of the center pin 14, and from the center hole 1b toward the outer peripheral portion,
Since the sheets are sequentially bonded to the sheet 4, the disk substrate 1 and the sheet 4 can be bonded to each other while keeping a sufficient clearance at the outer peripheral portion. Therefore, since the outer peripheral portion of the disk substrate 1 does not contact the sheet 4 before the pressure bonding, it is possible to prevent the occurrence of uneven bonding.

Further, in the fifth embodiment, the disk outer peripheral support portion 41 is constituted by a plurality of pins, and these pins are formed on a virtual circle having a diameter larger than the diameter of the disk substrate 1. The disk substrate 1 is pressed by the elastic film 16 which expands due to the difference between the pressure in the main chamber 17 and the pressure in the sub-chamber 18 by being inclined toward the center of the center pin 14. As a result, the disk outer peripheral supporting portion 41 escapes from the outer peripheral portion of the disk substrate 1 to the outside, and at the stage of bonding, the disk outer peripheral supporting portion 4
1, the sheet 4 having a diameter equal to the diameter of the disk substrate 1 is provided on one main surface of the disk substrate 1.
Can be pasted together. Therefore, in the optical disk in which the light transmitting layer 2 is formed by bonding the light transmitting sheet 2a to which the adhesive layer 2b is adhered, even in the area where the light transmitting layer could not be formed conventionally, Since the light transmitting layer can be formed, the area of the recording area can be increased, and the storage capacity of the optical disk can be increased without reducing the size of the land or groove in the information signal section 1c.

Although the embodiments of the present invention have been specifically described above, the present invention is not limited to the above-described embodiments, and various modifications based on the technical idea of the present invention are possible.

For example, the numerical values, materials, the laminated structure of the information signal portion, and the type of the optical disk described in the above-described embodiment are merely examples, and different numerical values, materials, and the laminated structure of the information signal portion may be used as necessary. Alternatively, the type of optical disk may be used.

For example, as the optical disc manufactured in the above-described first to fifth embodiments, the information signal section 1c is provided only on one main surface of the disc substrate 1, but the first to fifth embodiments are described. The thickness of the disk substrate 1 according to the embodiment is set to about 0.6 mm, two disk substrates 1 are prepared, and the information signal portion 1c and the light transmitting layer 2 are formed on one main surface of each disk substrate 1. By manufacturing two optical disks and bonding the other main surfaces of the respective disk substrates 1 of these two optical disks via an adhesive such as an ultraviolet curable resin or a pressure-sensitive adhesive, the optical disk It is also possible to manufacture an optical disc capable of recording and / or reproducing information signals on both sides. In such an optical disc having an information signal section 1c capable of recording and / or reproducing information signals on both sides, the recording capacity can be doubled,
Specifically, an optical disk having a storage capacity of about 44 GB can be manufactured.

For example, in the above-described first embodiment, Al is used as the material of the reflection film constituting the information signal portion 1c. However, as the material of the reflection layer, an Al alloy, Silver (Ag), Ag alloy, copper (Cu), C
It is also possible to use a u alloy or the like. In the first embodiment, GeS is used as the phase change recording layer.
Although a material made of a bTe alloy is used, other materials such as a GeInSbTe alloy can be used for the phase change recording layer.

In the first embodiment described above,
The sheet 4 is composed of the light transmissive sheet 2a and the adhesive layer 2b, and a second protective film made of PET or PEN for protecting the light transmissive sheet 2a is provided on the light transmissive sheet 2a side of the sheet 4. Alternatively, the seat 4 may be configured. By providing the second protective film in this way, even when the sheet 4 is placed on the sheet placing surfaces 13a and 40a and fixed by suction, the sheet placing surfaces 13a and 40a are attached to the light transmitting sheet 2a. Since it is possible to prevent direct contact of the foreign matter on the light transmitting sheet 2a
It is possible to prevent the occurrence of scratches and the like. Also,
At this time, a slightly tacky adhesive (not shown) is adhered to the surface of the second protective film on the light transmitting sheet 2a side, and a layer made of this slightly tacky adhesive is applied. The light transmissive sheet 2a and the second protective film are adhered to each other through the intermediary. Here, the slightly tacky adhesive is made of an adhesive material having a larger adhesive force with the second protective film than the adhesive force with the light transmissive sheet 2a. The peeling of the protective film 2 from the protective film is performed at the interface between the light-transmitting sheet 2a and the layer made of the slightly tacky adhesive. The thickness of the above-mentioned protective film and the second protective film are each 40 μm.
Needless to say, it is not limited to this value.

When it is necessary to increase the frictional force when the optical disc according to the first embodiment is clamped and rotated in the clamp area 3, for example, the first to fifth embodiments described above are used. In the optical disc according to the above, the surface of the light transmitting layer 2 is subjected to a hard coat treatment,
In a case where the surface lubricity is improved, the clamp reference surface 3a may be selectively roughened by glow discharge or sandblasting to make the clamp reference surface 3a less slippery. good. At this time, the roughening is performed selectively with respect to the clamp reference surface 3a. Specifically, the roughening is performed so that the surface roughness Ra is, for example, 30 nm or more, preferably 120 nm or more.

In the first to fourth embodiments described above, a vacuum suction hole may be provided on the flat stage 13. When such a bonding apparatus is used, the sheet 4 is placed on the sheet placing surface 13a, and the inside of a vacuum suction hole (not shown) provided in the sheet placing surface 13a is evacuated. Thus, the sheet 4 can be sucked while being kept flat on the sheet mounting surface 13a. Thus, by adsorbing the sheet 4 on the sheet mounting surface 13a, the sheet 4 can be adsorbed and fixed in a planar shape, so that the reliability in bonding can be improved. In addition, a vacuum suction hole is provided,
When the sheet 4 is fixed by suction on the flat stage 13, it is needless to say that the pressure inside the vacuum suction hole is controlled to be smaller than the pressure inside the main chamber 17. In addition, release of adsorption fixation by this vacuum adsorption hole
Considering the timing at which the center pin 14 projects,
It is desirable that the pressing be performed during the pressure bonding of the disk substrate 1 and the sheet 4 before the main chamber 17 is opened to the atmosphere or simultaneously with the opening to the atmosphere.

Also, for example, in the above-described fifth embodiment, the arrangement of the individual pins constituting the disk outer periphery supporting portion 41 provided on the flat stage 13 is set as shown in FIG. As shown in FIG. 14A, the individual pins constituting the disk outer periphery supporting portion 41 provided on the plane stage 40 are inscribed in a virtual circle centered on the center of the center pin 14 and the substrate positioning pin 15. It may be arranged at the positions of the vertices of the quadrilateral.
As shown in FIG. 4B, the individual pins may be arranged at the positions of the vertices of a regular pentagon, and as shown in FIG.
Each pin may be arranged at the position of a vertex of a regular hexagon.

[0156]

As described above, according to the present invention, one main surface of a disk substrate is pressed against at least a sheet composed of a light-transmitting sheet and an adhesive layer, and the sheet and the disk substrate are bonded via the adhesive layer. A first processing chamber configured to be able to store a sheet and a disk substrate and capable of storing a sheet and a disk substrate, and a second processing chamber configured to be capable of at least depressurizing and opening to the atmosphere. By setting the pressure inside the first processing chamber to be lower than the pressure inside the second processing chamber, the partition portion made of an elastic body provided between By pressing against the other main surface of the disk substrate and pressing the one main surface of the disk substrate and the adhesive layer of the sheet, the optical disk manufacturing apparatus can be reduced in size, and the space saving of this apparatus can be reduced. To do Kill with, at the time of forming the light transmitting layer, or cause wrinkles adhesion unevenness, bubbles between the adhesive layer and the disc substrate can be prevented or to contamination. Therefore, it has a light transmitting layer that is thin, has small birefringence, has good transparency, and has a uniform thickness, and has a high NA of the objective lens.
It is possible to manufacture an optical disk having high reliability which can sufficiently cope with the development.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an optical disc according to a first embodiment of the present invention.

FIG. 2 is a sectional view showing the disk substrate according to the first embodiment of the present invention.

FIG. 3 is a sectional view showing a sheet according to the first embodiment of the present invention.

FIG. 4 is a flowchart for explaining a method of manufacturing the optical disc according to the first embodiment of the present invention.

FIG. 5 is a schematic diagram illustrating a bonding apparatus according to the first embodiment of the present invention.

FIG. 6 is a schematic diagram illustrating a pressed state of the disk substrate in the bonding apparatus according to the first embodiment of the present invention.

FIG. 7 is a schematic diagram illustrating a change in an elastic film in the bonding device according to the first embodiment of the present invention.

FIG. 8 is a schematic diagram illustrating a bonding device according to a second embodiment of the present invention.

FIG. 9 is a schematic diagram illustrating a bonding device according to a third embodiment of the present invention.

FIG. 10 is a schematic diagram illustrating a bonding device according to a fourth embodiment of the present invention.

FIG. 11 is a schematic diagram illustrating a bonding apparatus according to a fifth embodiment of the present invention.

FIG. 12 is a plan view showing a sheet holding unit in a bonding apparatus according to a fifth embodiment of the present invention.

FIG. 13 is a sectional view showing details of a disk outer peripheral support portion of a bonding apparatus according to a fifth embodiment of the present invention.

FIG. 14 is a plan view showing another example of the arrangement of the pins constituting the disk outer peripheral support portion of the bonding apparatus according to the fifth embodiment of the present invention.

FIG. 15 is a schematic diagram illustrating a bonding device according to a conventional technique.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Disk substrate, 1a ... Replica substrate, 1b
... Center hall, 1c ... Information signal part, 2 ...
・ Light transmitting layer, 2a ・ ・ ・ Light transmitting sheet, 2b ・ ・ ・ Adhesive layer, 2c ・ ・ ・ Through hole, 3 ・ ・ ・ Clamp area, 3a
... Clamp reference plane, 4 ... Sheet, 10 ... Laminating device, 11 ... Base plate, 12 ...
Bell jar, 12a... O-ring, 12b... Elastic film holding part, 13, 40.
40a: sheet mounting surface, 14: center pin,
14a: disk substrate mounting surface, 15: substrate positioning pin, 16: elastic film, 16a, 16d ...
Low elasticity membrane, 16b, 16c ... High elasticity membrane, 17.
..Main chamber, 18 ... Subchamber, 1
9, 21 ... piping, 20, 22, 31, 32 ... branch piping, 23 ... vacuum pump, 24, 25, 26, 2
7, 28, 34 ... valve, 33 ... pressurizing device, 3
4 ... Valve, 40a ... Sheet mounting surface, 41 ...
· Disk outer peripheral support portion, 42 · · · coil spring, 43 ·
..Space, 44... Outer peripheral support moving mechanism

Claims (31)

[Claims] 1. A laser used for recording and / or reproducing the information signal on at least one main surface of the disk substrate on which an information signal section configured to record and / or reproduce an information signal is provided. A light-transmitting sheet configured to transmit light, and an adhesive layer configured to be capable of bonding the light-transmitting sheet to one main surface of the disk substrate and configured to transmit the laser light. A manufacturing apparatus for an optical disk configured to be able to be bonded to a sheet via the adhesive layer, wherein the pressing means is configured to be able to press the other main surface of the disk substrate opposite to the one main surface. A first processing chamber, wherein the pressing means is configured to be openable to the atmosphere and capable of being depressurized and configured to allow the disk substrate and the sheet to be placed thereon; And a partition provided between the second processing chamber and the second processing chamber configured to be capable of reducing pressure. The partition is made of an elastic body, and the pressure inside the first processing chamber is increased by the second processing chamber. An apparatus for manufacturing an optical disk, wherein the partition is configured to be able to be pressed against the other main surface of the disk substrate by making the pressure lower than the pressure inside the processing chamber. 2. The disk substrate has a planar annular shape, the sheet has a planar annular shape, and a center axis of the disk substrate in a direction perpendicular to one main surface of the disk substrate; 2. The optical disc manufacturing apparatus according to claim 1, wherein the optical disc manufacturing apparatus is configured to be arranged so that a central axis in a direction perpendicular to a surface of the sheet in (1) coincides with the center axis. 3. The disk drive according to claim 2, wherein the one main surface of the disk substrate and the adhesive layer of the sheet are arranged so as to be separated from each other while being substantially parallel to each other. Optical disk manufacturing equipment. 4. The optical disk manufacturing apparatus according to claim 3, wherein a distance between said disk substrate and said sheet is set to be 1.0 mm or more and 5.0 mm or less. 5. The disk drive according to claim 1, wherein the partition has a flat disk shape, and the center of the flat disk shape of the partition overlaps a central axis of the disk substrate in a direction perpendicular to the one main surface. 3. The apparatus for manufacturing an optical disk according to claim 2, wherein: 6. The pressure inside the first processing chamber is made smaller than the pressure inside the second processing chamber,
When the partition portion is pressed against the other main surface of the disk substrate, the partition portion is configured to be rotationally symmetric with respect to the center axis of the disk substrate. An optical disk manufacturing apparatus according to claim 5. 7. The elastic member according to claim 5, wherein the partition portion is made of an elastic film, and an elastic modulus of an outer peripheral portion of the elastic film is larger than an elastic modulus of an inner peripheral portion of the elastic film. Optical disk manufacturing equipment. 8. The elastic member according to claim 5, wherein the partition portion is made of an elastic film, and an elastic modulus of an outer peripheral portion of the elastic film is smaller than an elastic modulus of an inner peripheral portion of the elastic film. Optical disk manufacturing equipment. 9. A disk substrate holding unit configured to hold the sheet, the sheet holding unit configured to be capable of holding the disk substrate,
A disk outer peripheral supporting portion configured to support an outer peripheral portion of the disk substrate, wherein the disk outer peripheral supporting portion is configured to be buried and protrudable with respect to the sheet holding means, and 3. The optical disk manufacturing apparatus according to claim 2, wherein a projecting direction of the outer peripheral support portion is inclined toward a central portion of the disk substrate holding means. 10. An opening is formed in a center portion of said disk substrate, said disk substrate holding portion is configured to be able to fit into said opening of said disk substrate, and said opening of said disk substrate is provided to said disk substrate holding means. The optical disk manufacturing apparatus according to claim 9, wherein the optical disk manufacturing apparatus is configured to be held by being fitted. 11. The apparatus for manufacturing an optical disk according to claim 9, wherein said disk outer peripheral supporting portion is constituted by a plurality of pins. 12. The optical disk manufacturing apparatus according to claim 11, wherein said plurality of pins are provided along a virtual circumference concentric with the center of said disk substrate holding means. 13. The optical disk manufacturing apparatus according to claim 12, wherein the plurality of pins are provided at positions of vertexes of a regular polygon inscribed in the virtual circumference. 14. The optical disk manufacturing apparatus according to claim 1, wherein a distance between the other main surface of the disk substrate and the partition portion is 5 mm or more and 70 mm or less. 15. The optical disk manufacturing apparatus according to claim 1, wherein the inside of the first processing chamber can be pressurized to a pressure higher than the atmospheric pressure. 16. The optical disk manufacturing apparatus according to claim 1, wherein said elastic body is made of silicone rubber or nitrile rubber. 17. An information signal portion capable of recording and / or reproducing an information signal on one main surface of a disk substrate, and a laser beam used for recording and / or reproducing the information signal can be transmitted therethrough. The light transmitting layer is formed by sequentially laminating the light transmitting layer, the light transmitting layer being capable of transmitting the laser light, and the light transmitting sheet being the main member of the disk substrate. A laser light transmitting adhesive layer to be bonded to a surface, the main surface of the disc substrate, by pressing at least a sheet comprising the light transmitting sheet and the adhesive layer, the sheet and What is claimed is: 1. A method for manufacturing an optical disk, comprising: a step of bonding the disk substrate with the disk substrate, wherein the substrate and the disk substrate can be stored under reduced pressure and open to the atmosphere. A first processing chambers, is provided between the second processing chamber configured to allow at least evacuable and air release, the partitioning portion made of an elastic body,
By making the pressure inside the first processing chamber smaller than the pressure inside the second processing chamber, by pressing against the other main surface of the disk substrate opposite to the one main surface, A method for manufacturing an optical disk, wherein one main surface of a disk substrate and the adhesive layer of the sheet are pressure-bonded. 18. The disk substrate has a planar annular shape, the sheet has a planar annular shape, and a center axis of the disk substrate in a direction perpendicular to a surface of the disk substrate; 18. The method of manufacturing an optical disk according to claim 17, wherein the optical disk is arranged so that a center axis in a direction perpendicular to a surface of the sheet coincides with the center axis. 19. The method for manufacturing an optical disk according to claim 18, wherein said one main surface of said disk substrate and said adhesive layer of said sheet are set apart from each other while being substantially parallel to each other. 20. The method for manufacturing an optical disk according to claim 19, wherein a distance between said disk substrate and said sheet is set to be 1.0 mm or more and 5.0 mm or less. 21. The partitioning section makes the partition inside the other main surface of the disk substrate by making the pressure inside the first processing chamber smaller than the pressure inside the second processing chamber. When being pressed, the disk substrate is made of an elastic film configured to be rotationally symmetrical with respect to the center axis, and the elastic modulus of the outer peripheral portion of the elastic film is set to a value within the elastic film. 19. The method for manufacturing an optical disk according to claim 18, wherein the elastic modulus is larger than a peripheral portion. 22. The partitioning section makes the partition inside the other main surface of the disk substrate by making the pressure inside the first processing chamber smaller than the pressure inside the second processing chamber. When being pressed, the disk substrate is made of an elastic film configured to be rotationally symmetrical with respect to the center axis, and the elastic modulus of the outer peripheral portion of the elastic film is set to a value within the elastic film. 19. The method for manufacturing an optical disk according to claim 18, wherein the elastic modulus is smaller than the elastic modulus of the peripheral portion. 23. A sheet holding device configured to hold the sheet, wherein the sheet holding device includes a disk substrate holding portion configured to hold the disk substrate, and an outer peripheral portion of the disk substrate. A disk outer peripheral support configured to be capable of being supported, the disk outer peripheral support being configured to be immersible and protrudable with respect to the sheet holding means, and that the direction of projection of the disk outer peripheral support is 18. The method for manufacturing an optical disk according to claim 17, wherein the optical disk is inclined toward a center of the disk substrate holding portion. 24. As the disk substrate is pressed by the partition portion, the disk outer peripheral supporting portion moves to the outer peripheral side of the disk substrate, and the disk outer peripheral supporting portion moves by the disk outer peripheral supporting portion before the pressing of the disk substrate is completed. The method for manufacturing an optical disk according to claim 23, wherein the support is released. 25. At the start of the pressing, the distance between the outer peripheral portion of the disk substrate and the outer peripheral portion of the sheet is
24. The method for manufacturing an optical disk according to claim 23, wherein the distance is set to 1.0 mm or more and 5.0 mm or less. 26. The apparatus according to claim 23, wherein said sheet holding means fixes the sheet by suction.
A manufacturing method of the optical disc according to the above. 27. The method of manufacturing an optical disk according to claim 17, wherein a distance between the other main surface of the disk substrate and the partition portion is 5 mm or more and 70 mm or less. 28. The method according to claim 17, wherein the inside of the second processing chamber is pressurized to a pressure higher than the atmospheric pressure. 29. The method of manufacturing an optical disk according to claim 28, wherein the pressure inside the second processing chamber is set to 151988 Pa or more and 506625 Pa or less when the disk substrate and the sheet are bonded. 30. When the disk substrate is bonded to the sheet, the pressure in the first processing chamber is set to 4.0 × 1.
18. The method for manufacturing an optical disk according to claim 17, wherein the pressure is set to not less than 0 ² Pa and not more than 2.0 × 10 ⁵ Pa. 31. The method for manufacturing an optical disk according to claim 17, wherein said elastic body is silicone rubber or nitrile rubber.