JP2005216426A - Method for manufacturing optical disk - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To laminate a disk substrate to a cover sheet while surely adhering the cover sheet to the mounting surface of a support table even when the cover sheet tends to be deformed. <P>SOLUTION: In the device for manufacturing an optical disk, when a cover sheet 24 is mounted on the mounting surface 49 of a support table 48, an air flow is jetted from an air nozzle 142, this air flow is sprayed to the cover sheet 24, and the cover sheet 24 is attracted on the mounting surface 49 by an electrostatic chuck 132 disposed in the support table. Thus, even when the cover sheet 24 tends to be deformed, while the cover sheet 24 is corrected to be flat by the air flow, the entire cover sheet 24 is adhered on the mounting surface of the support table by electrostatic power from the electrostatic chuck 132. Then, the disk substrate 12 is mounted on the cover sheet 24 in vacuum atmosphere, and the disk substrate 12 is pressed to be laminated to the cover sheet 24. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an optical disk manufacturing method for manufacturing an optical disk by bonding a thin cover sheet on a recording surface of a disk substrate.

  As an optical disk for recording or reproducing information using laser light, for example, CD-R (Compact Disc-recordable), CD (Compact Disc), DVD (digital versatile disc), DVD-R (digital versatile disc- In recent years, there has been a demand for storing a larger amount of information such as video information, and studies on increasing the density of recorded information have been made. The information recording density for such an optical disk is generally determined by the spot size of the light beam on the disk, and this spot size is proportional to λ / NA, where λ is the laser wavelength and NA is the numerical aperture of the objective lens. For this reason, in order to increase the recording density on the optical disc, it is necessary to shorten the wavelength of the laser beam and to increase the NA of the objective lens is effective. However, since the coma generated by the tilt of the optical disk increases in proportion to the third power of the NA, the margin for the tilt due to the tilt of the disk becomes extremely small by increasing the NA, and even a slight tilt causes the beam spot to be blurred and high Recording and reproduction at a density cannot be realized. Therefore, in a conventional optical disc suitable for high density, the cover layer, which is a laser light transmission layer, is sufficiently thin (for example, about 0.1 mm), and the coma aberration increases due to the disc tilt with high NA. (For example, refer to Patent Document 1).

  In the optical disc production line as described above, for example, a thin cover sheet based on a resin film is bonded onto the recording surface of a disc substrate on which an information recording layer has been formed in advance, and this cover sheet is used to An optical disc is manufactured by forming a transparent cover layer. Here, the cover sheet is composed of a resin film and an adhesive film formed on one surface of the resin film. When the cover sheet is bonded to the disc substrate, first, the disc substrate is overlaid on the adhesive film of the cover sheet, and a laminate of the cover sheet and the disc substrate (hereinafter referred to as “disc laminate”). Configure. In this state, the entire adhesive film is not uniformly adhered to the recording surface of the disk substrate, and the cover sheet is not bonded to the disk substrate with a sufficient bonding force. For this reason, in the optical disc production line, the disc stack is pressed with a predetermined pressure along the thickness direction thereof, and the entire cover sheet is uniformly adhered to the recording surface of the disc substrate. Thereby, the cover sheet in the disk laminate is bonded to the disk substrate with a sufficient bonding force, and an optical disk is manufactured as a product material.

  As a manufacturing apparatus for manufacturing the above optical disk (hereinafter referred to as “optical disk manufacturing apparatus”), for example, as disclosed in Patent Document 2, a disk is placed on a cover sheet placed on a support table. After stacking the substrates, storing the disk substrate and cover sheet in a vacuum chamber and reducing the pressure to a predetermined degree of vacuum, the disk substrate is placed on a support table by a pad that is a pressure member having elasticity in the vacuum chamber. Some pressurize the cover sheet and attach the cover sheet to the recording surface of the disk substrate. In this way, the bonding step of bonding the cover sheet to the recording surface of the disk substrate is performed in a vacuum atmosphere reduced to a sufficiently high degree of vacuum so that the space between the cover sheet bonded to the disk substrate and the recording surface is reduced. As a result, it is possible to effectively prevent the cover sheet and the recording surface of the disk substrate from being incompletely adhered.

In addition, a circular opening and a center hole are respectively formed in the center of the cover sheet and the disk substrate as described above, and in the optical disk manufacturing apparatus, a center pin protruding from the center of the support table is provided on the cover sheet. The cover sheet and the disc substrate are respectively positioned so that the centers thereof coincide with each other by being inserted into the opening and the center hole of the disc substrate.
Japanese Patent Laid-Open No. 11-31337 (page 9-10, FIG. 4) Japanese Patent Laid-Open No. 2003-217192 (page 8, FIG. 1 and FIG. 2)

  However, when an optical disc is manufactured by the optical disc manufacturing apparatus as described above, if the cover sheet placed on the support table has a deformation ridge such as a curl ridge, such a deformation ridge is attached. When the disk substrate is overlaid on the cover sheet, a gap may be locally generated between the disk substrate and the cover sheet. Even when the disc substrate and the cover sheet are pressed and bonded together by a pressure member in a vacuum atmosphere with the gap formed between the disc substrate and the cover sheet in this way, Air may not be completely discharged from between the cover sheet and minute bubbles (air) may remain between the cover sheet of the disk substrate. Such bubbles existing between the disc substrate and the cover sheet scatter laser light incident on the optical disc during recording and reproduction, and also deteriorate the appearance quality of the optical disc. It becomes.

  Also, if the cover sheet has a deformed ridge, the center pin is not inserted into the opening of the cover sheet placed on the support table so that the positioning accuracy of the center pin with respect to the cover sheet decreases. There is. As a result, the cover sheet and the disk substrate are bonded to each other with their centers not aligned, causing a positional shift between the cover sheet and the disk substrate, or pressurizing the disk substrate placed on the cover sheet. In some cases, part of the cover sheet slips in the plane direction with respect to the disk substrate, and the cover sheet is wrinkled.

  In view of the above facts, the object of the present invention is to attach the disc substrate to the cover sheet while securely attaching the cover sheet to the mounting surface of the support table even when the cover sheet has a deformation flaw. An object of the present invention is to provide a method of manufacturing an optical disc that can be matched.

  The method for producing an optical disk according to the present invention comprises a disk substrate having a recording surface on one side and an information recording layer formed on the recording surface, and an adhesive film formed on the one side of the resin film. And a cover sheet bonded to the recording surface so as to cover the information recording layer via the adhesive film, wherein the cover sheet is mounted on a mounting surface of a support table. The cover sheet is adsorbed on the support table by the disk substrate and the electrostatic chuck after the cover sheet is adsorbed on the mounting surface of the support table by the electrostatic chuck provided on the support table. Is held in a vacuum atmosphere depressurized to a predetermined degree of vacuum, and the recording surface of the disk substrate is placed on the adhesive film of the cover sheet, and the disk is interposed through the adhesive film. It characterized by having a bonding step of bonding the plate to the cover sheet.

  In the optical disk manufacturing method according to the present invention, first, the cover sheet is placed on the placement surface of the support table, and the cover sheet is placed on the placement surface of the support table by the electrostatic chuck provided on the support table. By adsorbing, the entire cover sheet can be brought into close contact with the mounting surface of the support table by the electrostatic force from the electrostatic chuck, so even if the cover sheet has a deformed surface such as a roll surface, the cover sheet It is possible to reliably prevent a part of the substrate from being lifted from the mounting surface of the support table.

  In the optical disk manufacturing method of the present invention, the recording surface of the disk substrate is then placed on the adhesive film of the cover sheet while the cover sheet adsorbed on the support table by the disk substrate and the electrostatic chuck is held in a vacuum atmosphere. And the disk substrate is bonded to the cover sheet through the adhesive film.

  As a result, for example, a part of the cover sheet is lifted from the support table, so that the air is not completely discharged between the cover sheet and the disk substrate overlaid on the cover sheet. Therefore, it is possible to effectively prevent minute bubbles (air) from remaining between the cover sheets of the disk substrates that are bonded to each other, and the cover sheet and the disk substrate are bonded so that their centers do not coincide with each other. When the disc substrate placed on the cover sheet is pressed and bonded together, the cover sheet slips in the plane direction with respect to the disc substrate. Thus, wrinkles can be effectively prevented from occurring on the cover sheet.

  As described above, according to the optical disk manufacturing method of the present invention, even when the cover sheet has a deformed wrinkle, the cover sheet is securely attached to the mounting surface of the support table, Disc substrates can be bonded together.

  Hereinafter, an optical disk manufacturing method according to an embodiment of the present invention will be described with reference to the drawings.

  First, the configuration of the optical disc according to the embodiment of the present invention will be described. FIG. 1 shows an optical disk manufactured by an optical disk manufacturing method according to an embodiment of the present invention. This optical disc 10 is capable of recording information at a high density with respect to an optical disc such as a conventional DVD-R. For example, the optical disc 10 has a shorter wavelength as a laser beam for recording and reproduction than a conventional optical disc. It is assumed that the blue-violet laser light is used and the numerical aperture NA of the objective lens of the disk drive device is increased to about 0.85, thereby increasing the single-side recording capacity for the 12 cm diameter optical disk 10 to about 27 Gbytes.

  The optical disk 10 is provided with a disk substrate 12 formed in a disk shape, and one surface of the disk substrate 12 is an information recording surface 14. A light reflecting layer 18 and a light absorbing layer 20 are sequentially laminated on the recording surface 14 side of the disk substrate 12, and an information recording layer (hereinafter simply referred to as “recording layer”) is formed by the light reflecting layer 18 and the light absorbing layer 20. 16) is configured. The optical disc 10 is provided with a transparent cover layer 22 on the disc substrate 12 so as to cover the recording layer 16. The cover layer 22 is composed of a cover sheet 24 made of a transparent resin, and has a thickness of about 100 μm.

  The disk substrate 12 is molded using a resin such as PC (polycarbonate). The cover sheet 24 includes a transparent resin film 26 such as PC (polycarbonate) or PET (polyethylene terephthalate) and an adhesive film 28 formed on one surface of the resin film 26. The pressure-sensitive adhesive film 28 is formed of a known acrylic, rubber-based, or silicon-based pressure-sensitive adhesive, and is preferably an acrylic pressure-sensitive adhesive from the viewpoint of transparency and durability. Further, the thicknesses of the resin film 26 and the adhesive film 28 in the cover sheet 24 are determined according to the set value of the cover layer 22, for example, when the set value of the thickness of the cover layer 22 is 100 μm, The thickness of the resin film 26 is set to 80 μm, and the thickness of the adhesive film 28 is set to 20 μm.

  A circular center hole 29 is formed in the center of the disk substrate 12 along the axis SD that is the rotation center of the optical disk 10. In addition, a circular opening 30 having a diameter larger than that of the center hole 29 around the axis SD is formed at the center of the cover layer 22.

  FIG. 2 shows an optical disk manufacturing apparatus according to an embodiment of the present invention. The optical disk manufacturing apparatus 40 is disposed on an optical disk manufacturing line, and is for manufacturing the optical disk 10 by bonding the cover sheet 24 to the disk substrate 12 formed by molding or the like. The optical disk manufacturing apparatus 40 includes: The disc substrate 12 and the cover sheet 24 manufactured through independent processes in the optical disc production line are supplied.

  The optical disc manufacturing apparatus 40 is provided with a main body casing 42 having a built-in control unit 38 (see FIG. 4) for controlling the entire apparatus. The 1st turntable 44 of a shape is installed. The first turntable 44 is rotatably supported by the main body casing 42 around the axis S1. On the outer peripheral side of the first turntable 44, six table bases 46 each formed in a disk shape are arranged at an equal pitch along the circumferential direction centering on the axis S1. A disk-shaped support table 48 is coaxially disposed on each of these table bases 46. As shown in FIG. 3, the upper surface of the support table 48 is a mounting surface 49 formed of a smooth plane, and the cover sheet 24 and the disk substrate 12 can be mounted on the mounting surface 49. Yes.

  Each support table 48 is provided with a center pin 50 so as to protrude from the center of the mounting surface 49. As shown in FIG. 4, the center pin 50 is slidably inserted into slide holes 52 penetrating the first turntable 44, the table base 46 and the support table 48. It protrudes from the center of the 48 mounting surfaces 49. The center pin 50 is formed in a substantially round bar shape and is disposed coaxially with the support table 48.

  As shown in FIG. 3, the center pin 50 is provided with a small-diameter portion 54 having a smaller outer diameter than the base end side at the distal end portion. The small diameter portion 54 has an outer diameter slightly smaller than the inner diameter of the center hole 29 of the disk substrate 12. Further, the center pin 50 is a large-diameter portion 56 having a constant outer diameter with respect to the small-diameter portion 54, and the outer diameter of the large-diameter portion 56 is that of the opening 30 of the cover sheet 24. It is slightly smaller than the inner diameter. In the center pin 50, a stepped disk support portion 58 is formed between the small diameter portion 54 and the large diameter portion 56.

  As shown in FIG. 4, the center pin 50 has a lower end projecting into the main body casing 42, and a block-shaped joint member 60 is attached to the lower end of the center pin 50. A first linear actuator 62 is disposed in the main body casing 42 below the center pin 50. The first linear actuator 62 includes a cylinder 64 and a drive rod 66 protruding upward from the cylinder 64, and the drive rod 66 is supported by the cylinder 64 so as to be slidable along the height direction (arrow H direction). Yes. A joint member 61 is attached to the tip of the drive rod 66, and the drive rod 66 is detachably connected to the center pin 50 via joint members 60 and 61.

  Here, the cylinder 64 of the first linear actuator 62 is fixed to a position corresponding to the rotation position P3 in the main body casing 42 via a bracket (not shown), and the first turntable 44 rotates and the cover sheet 24 is rotated. When the support table 48 on which the disk substrate 12 is placed moves to the orbiting position P3, the joint member 60 of the center pin 50 disposed on the support table 48 is inserted into the joint member 61 of the drive rod 66. Connected. Further, after the bonding of the cover sheet 24 and the disk substrate 12 on the support table 48 is completed, when the first turntable 44 rotates and the support table 48 is detached from the rotation position P3, the joint member of the support table 48 60 is also detached from the joint member 61.

  The first linear actuator 62 is servo-controllable by the control unit 38 and raises or lowers the drive rod 66 by a predetermined movement amount at a speed corresponding to the control signal input from the control unit 38. Thereby, the center pin 50 changes the protrusion length from the mounting surface 49 of the support table 48 according to the movement amount of the drive rod 66.

  As shown in FIG. 3, the support table 48 includes a thick disc-shaped table body 130 and a sheet-like electrostatic chuck 132 attached to the upper surface portion of the table body 130. An upper surface portion of the electric chuck 132 forms a mounting surface 49 of the support table 48. As shown in FIG. 6, the electrostatic chuck 132 includes an electrode sheet 136 having a thin film-like printed electrode formed on the lower surface portion, a cable 138 connected to the printed electrode, and an insulation for insulating the printed electrode from the table body 130. It is constituted by the layer 140. The electrostatic chuck 132 is electrostatically attracted to the cover sheet 24 placed on the placement surface 49 of the support table 48 when a drive voltage is applied to the print electrodes by the control unit 38 through the cable 138. Force (Jansen-Rabeck force) is applied. In the present embodiment, a single-pole type electrostatic chuck 132 is used, but a bipolar-type electrostatic chuck may be used.

  As shown in FIG. 2, the optical disc manufacturing apparatus 40 includes a sheet supply unit 68, a disc supply unit 70, a second turntable 72 having a smaller diameter than the first turntable 44, and the outer periphery of the first turntable 44. A disk carry-out unit 74 is installed. In FIG. 2, the six support tables 48 are arranged along the rotation direction (counterclockwise) of the first turntable 44, starting from the support table 48 at the position where the cover sheet 24 is supplied by the sheet supply unit 68. The following description will be made assuming that the positions at which the table base 46 is held are the circumferential positions P1 to P6.

  The sheet supply unit 68 is disposed in the vicinity of the outer periphery of the support table 48 held at the rotation position P1. The sheet supply unit 68 is for supplying the cover sheet 24 onto the support table 48 at the rotation position P1. The disk supply unit 70 is disposed near the outer periphery of the orbiting position P2. The disk supply unit 70 has a disk base 76 on which a plurality of disk substrates 12 can be stacked, and a stack on the disk base 76. A transport arm 78 is provided for gripping one disk substrate 12 from the plurality of disk substrates 12 and transporting the disk substrate 12 onto the support table 48 at the rotation position P2.

  In the optical disc manufacturing apparatus 40, an air nozzle 142 is disposed above the support table 48 at the orbiting position P1, and a vacuum chamber 80 is disposed above the table base 46 at the orbiting position P3. Here, as shown in FIG. 6A, the air nozzle 142 is connected to an air supply source (not shown) for supplying pressurized air through the air pipe 144. Further, an electromagnetic valve 146 is disposed in the middle of the air pipe 144, and this electromagnetic valve 146 can be opened and closed in accordance with a control signal from the control unit 38. The air nozzle 142 has its air injection opening opened toward the mounting surface 49 of the support table 48, and the pressurized air supplied from the air supply source when the electromagnetic valve 146 is opened is used as a radial air flow as the support table. 48 is ejected to the mounting surface 49 side.

  As shown in FIG. 4, the vacuum chamber 80 is formed in an open container shape facing downward, and an elastic seal member (not shown) is attached to the lower end surface of the vacuum chamber 80 over the entire circumference. ing. In the optical disc manufacturing apparatus 40, a support frame 84 is disposed above the vacuum chamber 80. The support frame 84 is supported above the table base 46 in a state where the vacuum chamber 80 is suspended. A subframe 86 is fixed to the top surface portion of the vacuum chamber 80.

  As shown in FIG. 4, a second linear actuator 88 for moving the vacuum chamber 80 up and down is mounted on the support frame 84. The second linear actuator 88 includes a cylinder 90 fixed to the support frame 84 and a drive rod 92 that protrudes downward from the cylinder 90, and the tip of the drive rod 92 is coupled to the subframe 86. . The second linear actuator 88 is controlled by the control unit 38, and in accordance with a control signal from the control unit 38, the open position (see FIG. 4) where the vacuum chamber 80 is spaced above the table base 46 and the lower end surface of the vacuum chamber 80 are tabled. It is held at any one of the sealed positions (see FIG. 7) to be brought into pressure contact with the table 46. Here, an airtight chamber 94 sealed from the outside is formed in the vacuum chamber 80 held in the sealed position.

  A pressure member 96 formed in a substantially thick disk shape is supported in the vacuum chamber 80 so as to face the support table 48, and an elastic pad 98 having elasticity is provided on the lower surface portion of the pressure member 96. It is fixed. On the other hand, a third linear actuator 100 for supporting and driving the pressure member 96 is mounted on the subframe 86. The third linear actuator 100 includes a cylinder 102 fixed to the subframe 86 and a drive rod 104 protruding downward from the cylinder 102. The drive rod 104 is attached to the top plate portion of the vacuum chamber 80. The seal ring 106 is inserted into the vacuum chamber 80 and protrudes into the vacuum chamber 80, and its tip is connected to the center of the upper surface of the pressure member 96.

  The third linear actuator 100 is controlled by the control unit 38 in a state where the vacuum chamber 80 is held in the sealed position, and when the control signal is received from the control unit 38, the third linear actuator 100 waits the pressurizing member 96 above the support table 48. From the standby position (see FIG. 4), the cover sheet 24 placed on the support table 48 and the disk substrate 12 are lowered to a pressing position, and the cover sheet 24 and the disk substrate 12 are pressed by the pressing member 96. Thereafter, the pressure member 96 is returned to the standby position.

  As shown in FIG. 4, one end of a flexible hose 108 is connected to the vacuum chamber 80 so as to communicate with the inside, and a vacuum generator (not shown) such as a vacuum pump is connected through the flexible hose 108. Has been. This vacuum generator is also controlled by the control unit 38. When the vacuum chamber 80 is lowered to the sealed position and the airtight chamber 94 is formed, the control unit 38 sucks the air in the airtight chamber 94 by the vacuum generator. The inside of the airtight chamber 94 is depressurized to a predetermined vacuum level.

  The second turntable 72 is for temporarily storing the optical disk 10 manufactured on the first turntable 44, and as shown in FIG. 2, near the outer periphery of the support table 48 held at the rotating position P6. Is arranged. On the second turntable 72, there are provided four disk support bases 110 on which the disk substrate 12 can be placed along the circumferential direction centering on the axis S3. In FIG. 2, four disk support bases 110 are arranged along the rotation direction (counterclockwise direction) of the second turntable 72 starting from the disk support base 110 located closest to the first turntable 44. The following description will be made assuming that the held positions are the round positions R1 to R4, respectively.

  As shown in FIG. 2, the optical disc manufacturing apparatus 40 is provided with a disc carry-out unit 74 adjacent to the second turntable 72, and the disc carry-out unit 74 includes a plurality of disc substrates 12. An NG disk base 112 and a non-defective disk base 114 that can be loaded are provided, a support table 48 held at the circular position P6, a disk support base 110 held at the circular position R1, an NG disk base 112, and a non-defective disk base. A transport arm 116 for transporting the optical disk 10 is provided between 114.

  Further, in the optical disc manufacturing apparatus 40, the protective film 36 is provided from the surface (light incident surface) of the optical disc 10 above the disc support 110 held at the rotational position R2 in the second turntable 72 (see FIG. 5B). Is installed, and the flatness of the light incident surface of the optical disc 10 and the amount of inclination with respect to the axis SD are inspected above the disc support 110 held at the rotation position R3. A surface inspection unit 120 is installed for this purpose.

  The cover sheet 24 (see FIG. 3) to be bonded to the disk substrate 12 was formed on a long strip-shaped resin film 26 and one surface of the resin film 26 as shown in FIG. 5B. A laminated sheet material 32 having a four-layer structure comprising an adhesive film 28, a release sheet 34 attached to the adhesive film 28, and a protective film 36 attached to the surface of the resin film 26 opposite to the adhesive film 28 is provided. Manufactured as a processed material. Specifically, the cover sheet 24 is formed by punching the protective film 36, the resin film 26, and the adhesive film 28 in the laminated sheet material 32 into a disk shape with an annular punching blade (not shown). At this time, the release sheet 34 affixed to the adhesive film 28 of the cover sheet 24 is left as a long band without being punched by the punching blade. The long strip-shaped release sheet 34 is used as a carrier base for transporting the cover sheet 24 punched from the laminated sheet material 32. The laminated sheet material 32 from which the cover sheet 24 has been punched in this manner is once wound up in a roll shape and then loaded into the sheet supply unit 68 as shown in FIG.

  Next, a method for manufacturing the optical disk 10 using the optical disk manufacturing apparatus 40 configured as described above will be described.

  In the optical disc manufacturing apparatus 40, when the support table 48 moves to the rotation position P <b> 1, the sheet supply unit 68 peels one cover sheet 24 from the release sheet 34 in the laminated sheet material 32, and the cover sheet 24 is It mounts on the mounting surface 49 of the support table 48 so that the adhesive film 28 faces upward. At this time, the laminated sheet material 32 which is the material of the cover sheet 24 is stored in a rolled state and loaded into the sheet supply unit 68, so that the cover sheet 24 peeled from the release sheet 34 has In general, a curl ridge that tries to curl in the bending direction of the laminated sheet material 32 is attached, and the curled crease becomes stronger as the cover sheet 24 wound on the inner peripheral side of the laminated sheet material 32. When the cover sheet 24 with such strong curl ridges is placed on the placement surface 49 of the support table 48 by the sheet supply unit 68, as shown in FIG. 8 (A) or (B), A part of the cover sheet 24 in which the curl is generated is likely to remain in a state of being lifted from the mounting surface 49 of the support table 48.

  Specifically, when the laminated sheet material 32 is wound so that the surface (light incident surface) of the cover sheet 24 faces the outer peripheral side, the cover sheet 24 is as shown in FIG. Then, it curls so as to be convex toward the mounting surface 49, and both end portions along the radial direction on the mounting surface 49 are likely to float from the mounting surface 49, and the cover sheet 24. When the laminated sheet material 32 is wound up so that the light incident surface faces the inner peripheral side, the cover sheet 24 is concave toward the placement surface 49 as shown in FIG. 8B. And the central portion along the radial direction is likely to float from the mounting surface 49. At this time, as shown in FIG. 8A, when the vicinity of the center portion of the cover sheet 24 is lifted from the placement surface 49, the center pin 50 is inserted into the opening 30 of the cover sheet 24. The cover sheet 24 cannot be positioned with a predetermined accuracy by the large-diameter portion 56 of the center pin 50.

  In the optical disc manufacturing apparatus 40, when the cover sheet 24 is placed on the support table 48 by the sheet supply unit 68, the control unit 38 opens the electromagnetic valve 146 disposed in the air pipe 144 in synchronization with this. Thereby, an air flow is ejected radially from the air nozzle 142 and is sprayed toward substantially the entire upper surface of the cover sheet 24 placed on the placement surface 49. Since this air flow pressurizes the entire cover sheet 24 toward the mounting surface 49, for example, as shown in FIG. 8 (A) or (B), the cover is placed on the mounting surface 49. Even when a part of the sheet 24 is lifted from the placement surface 49, the cover sheet 24 is corrected to a flat shape by the pressure (air pressure) generated by the air flow, and the entire cover sheet 24 is placed on the placement surface. 49, and the cover sheet 24 can be reliably positioned with a predetermined accuracy by the large-diameter portion 56 of the center pin 50. At this time, if the amount and flow velocity of the air flow injected from the air nozzle 142 are appropriately adjusted in accordance with the rigidity in the bending direction of the cover sheet 24 and the maximum amount of curl that can be generated in the cover sheet 24, this air flow can be reduced. By spraying, the entire cover sheet 24 can be securely adhered to the placement surface 49.

  The control unit 38 applies a driving voltage to the electrostatic chuck 132 after opening the electromagnetic valve 146. As a result, the electrostatic chuck 132 causes an electrostatic adsorption force to act on the cover sheet 24 placed on the placement surface 49, and the entire cover sheet 24 is attracted onto the placement surface 49. The control unit 38 closes the electromagnetic valve 146 after the application of the drive voltage to the electrostatic chuck 132 is started, and stops the blowing of the air flow to the cover sheet 24. At this time, even if the cover sheet 24 has a roll hook, it is possible to reliably prevent a part of the cover sheet 24 from floating on the placement surface 49 due to the suction force from the electrostatic chuck 132.

  In the optical disc manufacturing apparatus 40, when the cover sheet 24 is attracted onto the mounting surface 49 of the support table 48 by the electrostatic chuck 132, the first turntable 44 is rotated by a predetermined amount of rotation (60 °) in the reflective clockwise direction. Then, the support table 48 on which the cover sheet 24 is placed is moved to the rotation position P2. When the support table 48 is moved together with the cover sheet 24 to the rotation position P2, the disk supply unit 70 grips one disk substrate 12 from the plurality of disk substrates 12 stacked on the disk table 76, and this disk substrate 12 Is transferred onto the support table 48 at the orbiting position P2, and the disc substrate 12 is placed on the disc support portion 58 of the center pin 50 while the center hole 29 is fitted into the outer peripheral side of the small diameter portion 54 of the center pin 50. To do.

  At this time, the center pin 50 is held at the upper limit position by the first linear actuator 62, and at the upper limit position, the distal end side of the large diameter portion 56 in the center pin 50 is located above the placement surface 49 as shown in FIG. 6. Protruding to Accordingly, as shown in FIG. 6B, the center of the disk substrate 12 is positioned by the small diameter portion 54 of the center pin 50 so as to coincide with the axis S2 of the support table 48, and the center pin 50 The disk substrate 12 is supported by the disk support portion 58 in a state of being separated above the cover sheet 24.

  In the optical disc manufacturing apparatus 40, when the disc substrate 12 is placed on the disc support 58 of the center pin 50 by the disc supply unit 70, the first turntable 44 is rotated 60 ° in the reflective clockwise direction, and the cover sheet 24 and The support table 48 supplied with the disk substrate 12 is moved to the orbiting position P3. When the support table 48 moves together with the cover sheet 24 and the disk substrate 12 to the orbiting position P3, the control unit 38 causes the second linear actuator 88 to move the vacuum chamber 80 from the open position to the sealed position as shown in FIG. To lower. Thereby, an airtight chamber 94 sealed from the outside is formed in the vacuum chamber 80. Next, the control unit 38 sucks air from the inside of the hermetic chamber 94 by the vacuum generator and depressurizes the inside of the hermetic chamber 94 to a predetermined degree of vacuum. At this time, the vacuum generator depressurizes the inside of the airtight chamber 94 to a target vacuum degree (30 Pa or less in the present embodiment) set from a range of 5 to 100 Pa, and the cover sheet 24 and the disk substrate 12 are bonded together. The inside of the airtight chamber 94 is maintained at 30 Pa or less until completion.

  In the vacuum atmosphere, the discharge phenomenon from the electrostatic chuck 132 is promoted, and a phenomenon in which the attracting force to the cover sheet 24 is reduced occurs. However, after the cover sheet 24 once comes into close contact with the placement surface 49, the placement surface Since the cover sheet 24 is difficult to peel off from 49, the state in which the cover sheet 24 is in close contact with the placement surface 49 is maintained even in a vacuum atmosphere.

  When the pressure inside the hermetic chamber 94 is reduced to 30 Pa or less, the control unit 38 lowers the center pin 50 at the upper limit position to a predetermined lower limit position by the first linear actuator 62. At this lower limit position, the center pin 50 is positioned below the mounting surface 49 so that the center pin 50 does not protrude from the mounting surface 49 of the support table 48 as shown in FIG. When the center pin 50 is lowered from the upper limit position to the lower limit position, the disk substrate 12 placed on the disk support portion 58 of the center pin 50 moves to the cover sheet 24 and the recording surface 14 of the disk substrate 12. Is placed on the adhesive film 28 of the cover sheet 24.

  When the center pin 50 is lowered to the lower limit position, the control unit 38 stops applying the driving voltage to the electrostatic chuck 132 and moves the pressing member 96 to the standby position by the third linear actuator 100 (see FIG. 7A). ) To the pressing position (see FIG. 7B), and the disk substrate 12 and the cover sheet 24 are pressed with a predetermined pressure by the elastic pad 98 of the pressing member 96. At this time, the electrostatic chuck 132 for which the application of the driving voltage is stopped gradually reduces the attracting force with respect to the cover sheet 24 and substantially eliminates the attracting force with respect to the cover sheet 24 during pressurization by the pressurizing member 96.

  Further, the control unit 38 is configured such that the control unit 38 selects a target value selected from the range of 0.2 kPa to 1.0 kPa of the pressure applied to the disk substrate 12 and the cover sheet 24 from the elastic pad 98 of the pressure member 96. In this embodiment, the driving force generated by the third linear actuator 100 is controlled so as to be 0.5 kPa), and after maintaining this driving force for a predetermined pressurizing time (for example, 0.2 seconds), The pressure member 96 is returned from the pressing position to the standby position by the three linear actuators 100. As a result, the entire recording surface 14 of the disk substrate 12 is uniformly adhered to the adhesive film 28 of the cover sheet 24, and the cover sheet 24 is bonded to the disk substrate 12 with a sufficient bonding force, so that the optical disk 10 as a product material (FIG. 1). Manufacture) is completed.

  When the pressure unit 96 is returned to the standby position, the control unit 38 opens the inside of the hermetic chamber 94 to the atmosphere through the vacuum generator, and then returns the vacuum chamber 80 from the sealed position to the open position by the second linear actuator 88. . Further, a static eliminator (not shown) is disposed on the outer peripheral side of the first turntable 44. This static eliminator is provided with a support table 48 and a support table 48 at the rotation position P3 when the vacuum chamber 80 returns to the open position. The upper optical disk 10 is sprayed with a neutralizing air charged with a polarity opposite to that of the electrostatic chuck 132 during operation, and the support table 48 and the optical disk 10 are neutralized.

  In the optical disc manufacturing apparatus 40, when the vacuum chamber 80 returns to the open position, the first turntable 44 is rotated counterclockwise to move the support table 48 on which the optical disc 10 is placed to the rotation position P5, and then further. Move to the orbiting position P6. In conjunction with this, the optical disc manufacturing apparatus 40 grips the optical disc 10 placed on the support table 48 at the circular position P6 by the transport arm 78 of the disc carry-out unit 74, and reverses the front and back of the optical disc 10, The optical disk 10 is placed on the disk support 110 at the rotation position R1 of the second turntable 72.

  The second turntable 72 rotates intermittently counterclockwise when the optical disc 10 is placed on the disc support 110 at the orbiting position R1, and the second turntable 72 moves the support table 48 on which the optical disc 10 is placed to the orbiting position. After temporarily stopping at R2 and the rounding position R3, respectively, it is moved to the rounding position R4. At this time, the peeling unit 118 peels the protective film 36 from the optical disk 10 placed on the disk support 110 that has once stopped at the rotation position R2, and collects the protective film 36.

  Further, the surface inspection unit 120 inspects the surface state of the upper surface (light incident surface) of the optical disk 10 placed on the disk support 110 that has been temporarily stopped at the rotation position R3, such as the flatness and the amount of inclination. The inspection result by the surface inspection unit 120 is transmitted to a control unit (not shown) of the optical disc manufacturing apparatus 40. Based on the inspection result by the surface inspection unit 120, the control unit determines whether the optical disk 10 transported to the rotation position R3 by the second turntable 72 is an NG product that does not satisfy a predetermined quality standard, or a quality standard. Judge whether the product is satisfied.

  After the inspection by the surface inspection unit 120 is completed, when the optical disk 10 is conveyed to the rotation position P4 by the second turntable 72, the control unit of the optical disk manufacturing apparatus 40 determines that the optical disk 10 at the rotation position P4 is an NG product. In this case, the optical disk 10 is gripped by the transport arm 116, transported from the disk support base 110 onto the NG disk base 112 and loaded on the NG disk base 112, and the optical disk 10 at the rotation position P4 is a good product. In some cases, the optical disk 10 is held by the transport arm 116, transported from the disk support base 110 onto the non-defective disk base 114, and loaded on the non-defective disk base 114. When the NG product and the non-defective optical disc 10 loaded on the disk bases 112 and 114 are stored up to a predetermined number of lots, other processes such as a re-inspection process and a painting process are performed from the disk bases 112 and 114. It is carried out to the apparatus etc. to be performed.

  As described above, in the optical disc manufacturing method according to the present embodiment, first, the cover sheet 24 is placed on the placement surface 49 of the support table 48, and an air flow is blown onto the cover sheet 24, and the cover sheet 24 is attracted onto the mounting surface 49 by the electrostatic chuck 132 provided on the support table, so that the cover sheet 24 is flattened by the air flow even when the cover sheet 24 has a curl ridge. Since the entire cover sheet 24 can be brought into close contact with the mounting surface of the support table by the electrostatic force from the electrostatic chuck 132, a part of the cover sheet is lifted from the mounting surface of the support table. It can be surely prevented from entering the state.

  In the optical disk manufacturing method according to this embodiment, the recording surface 14 of the disk substrate 12 is then held while the cover sheet 24 adsorbed on the support table 48 by the disk substrate 12 and the electrostatic chuck 132 is held in a vacuum atmosphere. After being placed on the adhesive film 28 of the cover sheet 24, the disk substrate 12 and the cover sheet 24 are pressed by the pressure member 96, and the disk substrate 12 is bonded to the cover sheet 24.

  As a result, for example, part of the cover sheet 24 is lifted from the mounting surface 49 of the support table 48, so that the cover sheet 24 and the disk substrate 12 overlaid on the cover sheet 24 are overlapped. It is possible to effectively prevent air from being incompletely discharged, and to prevent minute bubbles (air) from remaining between the cover sheet 24 of the disk substrate 12 bonded to each other, and the cover sheet 24 and the disk. The substrate 12 and the substrate 12 are bonded to each other so that their centers do not coincide with each other, so that a position (center) shift occurs between the cover sheet 24 and the disk substrate 12, or the disk substrate 12 superimposed on the cover sheet 24 is pressed. It is effective that the cover sheet 24 slides in the plane direction with respect to the disk substrate 12 when the pressure is applied by the cover 96, and the cover sheet 24 is wrinkled. To be prevented.

  In the optical disk manufacturing method according to the present embodiment, an air flow is blown onto the cover sheet placed on the placement surface 49 of the support table 48, and the cover sheet 24 is placed on the placement surface 49 of the support table 48 by this air flow. The electrostatic chuck 132 is started to operate while being pressurized, and the cover sheet is adsorbed on the mounting surface 49 of the support table by the electrostatic chuck 132. Even if a part of the cover sheet 24 is lifted from the mounting surface 49 by the pressure, the cover sheet 24 is corrected to a flat shape by the pressure (air pressure) generated by the air flow, and the entire cover sheet 24 is mounted. The cover sheet 24 can be attracted onto the placement surface 49 by the electrostatic chuck 132 while being in close contact with the placement surface 49.

  In the present embodiment, an air flow is blown onto the cover sheet 24. Of course, an air flow other than air, such as an inert gas or nitrogen, is blown onto the cover sheet 24 to pressurize the cover sheet 24 toward the placement surface 49. Alternatively, the vicinity of the outer peripheral edge of the cover sheet 24 may be pressed by pressing a pressing member from above, and the entire cover sheet 24 may be securely adhered to the placement surface 49.

  In the optical disk manufacturing method according to the present embodiment, the cover sheet 24 is sucked onto the mounting surface 49 of the support table 48 by the electrostatic chuck 132 and then sucked onto the mounting surface 49 of the disk substrate 12 and the support table 48. The covered cover sheet 24 is carried into the vacuum chamber 80, and the hermetic chamber 94 formed in the vacuum chamber 80 is depressurized to a predetermined degree of vacuum, and then the disk substrate 12 is put into the cover sheet 24 in the hermetic chamber 94. to paste together. As a result, an electrostatic chucking force is generated by the electrostatic chuck 132 under atmospheric pressure, and the cover sheet 24 can be sucked onto the mounting surface 49 by this chucking force, so that the discharge phenomenon from the electrostatic chuck 132 is suppressed. However, the cover sheet 24 can be effectively adsorbed by the electrostatic chuck 132.

1 is a perspective view showing a configuration of an optical disc according to an embodiment of the present invention. It is a top view which shows the structure of the optical disk manufacturing apparatus with which the manufacturing method of the optical disk which concerns on embodiment of this invention is implemented. It is a perspective view which shows the structure of the support table and center pin in the optical disk manufacturing apparatus shown by FIG. FIG. 3 is a side cross-sectional view showing a configuration of a vacuum tank and a mechanism for supporting and driving the vacuum tank in the optical disc manufacturing apparatus shown in FIG. 2. It is the perspective view and side sectional drawing which show the structure of the lamination sheet material which is the raw material of the cover sheet used for the manufacturing method of the optical disk which concerns on embodiment of this invention. (A) is a side view showing a state where an air flow is blown to a cover sheet placed on a support table, and (B) is a side view showing a state where a cover sheet and a disk substrate are placed on the support table. It is. (A) is a side sectional view showing a state in which the vacuum chamber is lowered to the sealed position and a sealed chamber is formed in the vacuum chamber, and (B) is a disk substrate in which the pressure member is lowered to the pressurized position in the sealed chamber. It is side surface sectional drawing which shows the state which pressurized the cover sheet. FIG. 7 is a side view showing a state where a cover sheet placed on a support table is curled and a part of the cover sheet is lifted from the placement surface.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Optical disk 12 Disc substrate 14 Recording surface 24 Cover sheet 28 Adhesive film 40 Optical disk manufacturing apparatus 48 Support table 49 Mounting surface 80 Vacuum chamber 94 Airtight chamber 132 Electrostatic chuck 142 Air nozzle

Claims (3)

A disc substrate having one side as a recording surface and an information recording layer formed on the recording surface, and an adhesive film formed on one side of the resin film, the information recording through the adhesive film A cover sheet bonded to the recording surface so as to cover a layer, and an optical disc manufacturing method comprising:
After placing the cover sheet on the mounting surface of the support table, and adsorbing the cover sheet on the mounting surface of the support table by an electrostatic chuck provided on the support table,
While holding the cover sheet adsorbed on the support table by the disk substrate and the electrostatic chuck in a vacuum atmosphere depressurized to a predetermined vacuum degree, the recording surface of the disk substrate is placed on the adhesive film of the cover sheet. A method of manufacturing an optical disc, comprising: a step of attaching the disc substrate to the cover sheet via the adhesive film.   An air flow is blown to the cover sheet placed on the mounting surface of the support table, and the electrostatic chuck is started to operate while pressurizing the cover sheet toward the mounting surface side of the support table by the air flow. The method of manufacturing an optical disk according to claim 1, wherein the cover sheet is attracted to the mounting surface of the support table by the electrostatic chuck. After adsorbing the cover sheet on the mounting surface of the support table by the electrostatic chuck,
Depressurizing the hermetic chamber in which the cover sheet adsorbed on the mounting surface of the disk substrate and the support table is stored to a predetermined vacuum degree, and bonding the disk substrate to the cover sheet in the hermetic chamber. 3. A method of manufacturing an optical disc according to claim 1 or 2,

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