JP2564984Y2 - Mask device for manufacturing disk-shaped recording media - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a mask device for manufacturing a disk-shaped recording medium used in a process of manufacturing a thin-film recording medium such as an optical disk by thin-film processing utilizing a discharge reaction. .

2. Description of the Related Art A substrate for an optical disk used for a digital audio disk, a video disk, a magneto-optical disk and the like is injection-molded to a thickness of about 1.2 mm using a plastic material such as polycarbonate and polymethyl methacrylate. Next, the central part of the injection molded substrate was punched out by a mechanical method to form a central hole.

Many plastic fragments were generated by this punching process, and often adhered to the substrate surface, particularly the inner wall portion of the center hole and its peripheral portion, due to static electricity or the like. These debris could not be easily removed even by cleaning such as air blow.

As shown in FIG. 3, a conventional disk-shaped recording medium manufacturing mask apparatus includes a substrate holder 13 on which a substrate 11 having a center hole 12 is placed, and a substrate holder 13 for fixing the substrate 11 to the substrate holder 13. Inner peripheral mask 14 and inner peripheral mask 14 are attached to substrate holder 13
The diameter of the shaft 15 of the inner peripheral mask 14 is set to a value substantially equal to the inner diameter of the center hole 12 of the substrate 11.

This is because if the center of the substrate 11 is not correctly aligned with the substrate holder 13, a region where a film is formed such as a recording film is eccentric and correct recording or reproduction is not performed. Substrate 11 against substrate holder 13
This is because the center was aligned.

In such a configuration, a part of the plastic fragments adhered to the inner wall of the center hole 12 is shaved off when the shaft portion 15 of the inner peripheral mask 14 is inserted into the center hole 12 of the substrate 11, and scattered. In some cases, the recording surface 17 moved to the recording surface 17 on the substrate surface.

[Problems to be Solved by the Invention] Accordingly, a recording film, a protective film, a reflective film, and the like are formed on the recording surface 17 on the surface of the substrate 11 while these fragments remain attached.
As disclosed in No. 75, evaporation, sputtering,
When a film is formed by a vacuum process such as ion plating,
In the case of a fragment having a relatively large shape, the moisture resistance is reduced due to a pinhole, and even in the case of a fragment having a small shape, this causes an error in recording and reproducing information.

Japanese Patent Application Laid-Open No. 63-33608, "Radius measuring apparatus" discloses that a concentricity of a recording track with respect to a center hole of a disc-shaped recording medium is measured while maintaining a horizontal surface of the disc-shaped recording medium while keeping the horizontal plane. At least three positioning claws are arranged on the same radius with respect to the center of rotation of the support for supporting the disc-shaped recording medium so that the diameter can match the center hole, and each claw advances and retreats by the same amount with respect to the center of rotation. An apparatus adapted to be caused is disclosed. However, this device does not mask the center hole of the disc-shaped recording medium from above and below, so that the support is temporarily engaged with the center hole with a minimum necessary contact area. Even in this case, when applied to a disk-shaped recording medium mask device, foreign matter scattered from the center hole of the disk-shaped recording medium adheres to the recording surface before film formation, which causes pinholes and the like. There are problems such as a decrease in moisture resistance and a tendency to cause an information recording / reproducing error.

JP-A-63-154308 "Replica apparatus" uses a tapered jig to position the substrate in order to manufacture an optical disk replica with less eccentricity, and performs positioning by the inner diameter of the substrate, and fixes the substrate by vacuum suction. There is disclosed an apparatus in which a taper jig is removed and a stamper is positioned from above by using a jig having a trapezoidal cross section. However, this is also characterized only by a method of positioning a stamper for producing a replica for an optical disk. Even if the pattern processed on the surface of the stamper and the inner diameter of the substrate can be made concentric, There is a problem that a vacuum source is required for fixing the film, and the film cannot be applied to a vacuum process or the like for film formation because the film is not portable in a positioning state.

Furthermore, Japanese Patent Application Laid-Open No. 1-78321 discloses a stamper holding device capable of fixing a stamper manufactured in an optical disk manufacturing process with high accuracy to a rotary table of a stamper inspection device or the like. Have been. However, this is also characterized in that the porous sheet is placed on a rotary table, and a stamper is placed thereon, so that the entire surface of the stamper can be suctioned and held with good flatness. Although a center guide with a tapered surface can be engaged with the center hole of the stamper to center the stamper, it is not portable in the centering state, and therefore cannot be applied to a vacuum process for film formation. It was something to hold.

Therefore, an object of the present invention is to reduce the amount of plastic debris adhering to the recording surface of the substrate surface during film formation, and to manufacture a disk-shaped recording medium with less pinholes and errors during recording and reproduction. An object of the present invention is to provide a manufacturing mask device.

[Means for Solving the Problems] In order to achieve the above object, the present invention provides a substrate having a center hole penetrating from the front surface to the back surface, leaving only a recording surface portion formed on the front surface around the center hole. A mask for producing a disc-shaped recording medium by forming a film on the recording surface portion and forming a non-film-forming area when producing a disc-shaped recording medium. And a substrate holder having a different diameter hollow spindle projecting from the support plate and engaging with the center hole, a shaft portion passing through the hollow portion of the different diameter hollow spindle, and the substrate being coupled to an upper end of the shaft portion. An inner peripheral mask having a dish portion which is locked to a non-film forming region on the surface around the center hole of the center hole, and the shaft portion of a portion extending below the support plate portion through the different diameter hollow spindle. And magnetically attracts the support plate. A cylindrical base having a bottomed cylindrical magnet to be stopped, wherein the different-diameter hollow spindle has a shaft length substantially equal to the center hole and having a shaft length necessary for positioning the center of the substrate or a length close thereto. And a peripheral portion having a diameter smaller than that of the central hole.

In the different diameter hollow spindle, the peripheral portion is formed of a first cylindrical portion having a diameter sufficiently smaller than the center hole, and the base portion is formed of a second cylindrical portion having substantially the same diameter as the center hole, or The different diameter hollow spindle is characterized in that the peripheral portion is formed of a truncated conical portion whose diameter is reduced from the diameter of the center hole toward the tip, and the base portion is formed of a cylindrical portion having substantially the same diameter as the center hole. Is what you do.

[Operation] According to the present invention, the small diameter hollow spindle has a small contact area with the center hole of the substrate, so that the plastic fragments attached to the inner wall of the center hole are prevented from moving when the substrate is mounted on the substrate holder. As a result, the amount of plastic fragments moving to the recording surface of the substrate surface is reduced, the contamination of the recording surface due to the mask in the non-film formation region can be prevented, and the problems of pinholes and errors during recording and reproduction can be solved.

Next, an embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a schematic sectional view showing one embodiment of a mask device for manufacturing a disc-shaped recording medium of the present invention.

In FIG. 1, reference numeral 1 denotes a substrate of a disk-shaped recording medium (optical disk, photo-sensitive disk, etc.), which is made of a plastic material such as polycarbonate or polymethyl methacrylate. 2 are perforated.
Reference numeral 3 denotes a substrate holder on which the substrate 1 is placed, 4 denotes an inner peripheral mask for fixing the substrate 1 to the substrate holder 3, and 5 denotes a magnet for locking the inner peripheral mask 4 to the substrate holder 3.

The substrate holder 3 is a support plate portion that supports the back surface of the substrate 1.
3a, and a hollow spindle 6 having a different diameter and projecting from the support plate 3a and engaging with the center hole 2. The inner peripheral mask 4 includes a shaft portion 4a that penetrates the hollow portion of the hollow spindle 6 having a different diameter, and a plate that is coupled to an upper end of the shaft portion 4a and that is locked to a non-film-forming region of the surface around the central hole 2 of the substrate 1. And a portion 4b. The magnet 5
It has a cylindrical shape with a bottom and covers the shaft portion 4a of a portion extending below the support plate portion 3a through the hollow spindle 6 having a different diameter and supporting the support plate portion.
Magnetically attracted and locked to 3a.

By the way, the hollow spindle 6 having a different diameter is a base (here, the second cylindrical portion 6b) having a shaft length substantially equal to that of the center hole 2 and having an axis length necessary for positioning the substrate 1 at a minimum or close thereto.
And a peripheral portion having a smaller diameter than the center hole 2 (here, the first cylindrical portion 6a). That is, the second cylindrical portion 6b is set to be sufficiently short with respect to the thickness of the substrate 1 so that the plastic fragments adhered to the inner wall of the center hole 2 of the substrate 1 are not moved as much as possible. Care has been taken to minimize the contact area between 6 and center hole 2.

In the mask state, the center hole 2 of the substrate 1 is sealed from above and below by the inner peripheral mask 4 and the substrate holder 3, and the substrate 1 whose back surface is supported by the support plate 3 a of the substrate holder 3 is Only the film forming region excluding the portion covered by the peripheral mask 4 is exposed, and the inside of the center hole 2 does not communicate with the outside. Further, in the masking process to reach the mask state, when the substrate 1 is placed on the substrate holder 3, the area of the hollow spindle 6 having the different diameter which is in contact with the inner wall of the center hole 2 is suppressed to a necessary minimum. In comparison, the amount of scraping off plastic debris adhered to the inner wall of the center hole 2 is greatly reduced, and the contact between the substrate 1 and the second cylindrical portion 6b is opposite to the back side of the substrate 1, that is, the recording surface 7. Since it is performed on the side, the scattering of plastic fragments almost never reaches the recording surface 7. Therefore, the contamination of the recording surface 7 due to the masking of the non-film formation region is prevented, and the problems of pinholes and errors during recording / reproducing that occur during film formation by a vacuum process such as vapor deposition, sputtering, or ion plating can be solved. it can. The hollow spindle 6 of different diameter is, of course, integrally molded. In addition, for example, a cylindrical projection (not shown) having the same diameter as the center hole 2 is also provided.
The substrate holder 3 can be easily formed by turning from the surface or by fitting a cylindrical body (not shown) corresponding to a step difference from the base 6b to a cylindrical projection having the same diameter as the peripheral part 6a. Can be manufactured.

In the above embodiment, the different diameter hollow spindle 6 is composed of the first cylindrical portion 6a having a small diameter and the second cylindrical portion 6b having a large diameter. It can also be.

In the embodiment shown in the figure, the peripheral portion of the hollow spindle 8 of different diameter provided in the substrate holder 3 is formed of a truncated conical portion 8a whose diameter is reduced from the diameter of the center hole 2 toward the tip, and the base portion is the center hole. 2 and a cylindrical portion 8b having substantially the same diameter as that of the second embodiment. Further, in this embodiment, the truncated conical portion 8a can function as a mounting guide or a centering guide for the center hole 2 of the substrate 1, and it is possible to prevent the substrate 1 from being caught during mounting.

[Effects of the Invention] As described above, the present invention masks a substrate having a center hole penetrating from the front surface to the back surface, leaving only a recording surface portion formed on the front surface around the center hole. When forming a non-film forming area by forming a film on the recording surface to form a disc-shaped recording medium, a different-diameter hollow spindle protruding from a substrate holder having a support plate portion for supporting the back surface of the substrate is used. Engage with the center hole of the substrate, insert the shaft of the inner peripheral mask into the hollow of the hollow spindle of the different diameter, and attach the plate coupled to the upper end of the shaft to the non-film formation area on the surface around the center hole of the substrate. The bottomed cylindrical magnet that covers the shaft of the part that extends below the support plate by inserting a hollow spindle with a different diameter is magnetically attracted and locked to the support plate. At this time, a part of the hollow spindle with a different diameter The base having the minimum or close to the axial length necessary for centering is engaged with the center hole, and the peripheral portion having a smaller diameter than the center hole is separated from the inner wall of the center hole. The substrate is sealed from above and below by the inner peripheral mask and the substrate holder, and only the film formation area of the substrate whose back surface is supported by the support plate of the substrate holder is exposed excluding the portion covered by the inner peripheral mask. In the mask state, the inside of the center hole does not communicate with the outside, and the contact area of the different diameter spindle that contacts the inner wall of the center hole is minimized, and the contact between the substrate and the different diameter hollow spindle is Since it is performed on the back side of the substrate, that is, on the side opposite to the recording surface, even in the masking process leading to the mask state, the scattering of plastic fragments and the like attached to the inner wall of the center hole of the substrate is satisfactorily suppressed. It prevents disc contamination on the recording surface due to the masking of the non-deposition area, and produces disc-shaped recording with few pinholes and errors during recording / reproduction during deposition by a vacuum process such as vapor deposition, sputtering or ion plating. It has excellent effects such as the ability to manufacture a medium.

Further, in the hollow spindle of different diameter, the peripheral portion is formed of a first cylindrical portion having a diameter sufficiently smaller than the center hole, and the base portion is formed of a second cylindrical portion having substantially the same diameter as the center hole. Needless to say, other than that, for example, turning from a cylindrical projection having the same diameter as the center hole or fitting a cylindrical body corresponding to a step difference from the base to the cylindrical projection having the same diameter as the peripheral portion, etc. The hollow spindle can be machined, and the substrate holder can be easily manufactured.

In addition, the hollow spindle of different diameter comprises a truncated conical portion in which the peripheral portion is reduced in diameter from the diameter of the center hole toward the tip, and the base portion is a cylindrical portion having substantially the same diameter as the center hole. The frusto-conical portion can function as a mounting guide or a centering guide for the center hole of the substrate, and it is possible to prevent the substrate from being caught during mounting.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view showing one embodiment of a mask device for manufacturing a disc-shaped recording medium of the present invention, and FIG. 2 is a schematic diagram showing another embodiment of a mask device for manufacturing a disc-shaped recording medium of the present invention. FIG. 3 is a schematic sectional view showing an example of a conventional mask device for manufacturing a disk-shaped recording medium. DESCRIPTION OF SYMBOLS 1 ... board | substrate 2 ... center hole 3 ... board holder 3a ... support plate part 4 ... inner peripheral mask 4a ... shaft part 4b ... dish part 5 ... magnet 6,8 ... hollow spindle 6a of different diameter ... First cylindrical portion (peripheral portion) 6b Second cylindrical portion (base portion) 7 Recording surface 8a Truncated conical portion 8b Cylindrical portion

Claims (3)

(57) [Scope of request for utility model registration] 1. A substrate having a center hole penetrating from a front surface to a back surface is masked except for a recording surface portion formed on the surface around the center hole, and a film is formed on the recording surface portion by forming a film on the recording surface portion. In a disk-shaped recording medium manufacturing mask device for partitioning and forming a non-film-forming region when a recording medium is manufactured, a support plate portion for supporting a back surface of the substrate and a central hole protruded from the support plate portion and associated with the center hole. A substrate holder having a different diameter hollow spindle to be combined, a shaft part passing through the hollow part of the different diameter hollow spindle, and a non-film formation region on the surface around the center hole of the substrate coupled to the upper end of the shaft part. An inner peripheral mask having a plate portion for stopping, a shaft portion of a portion extending below the support plate portion through the different diameter hollow spindle being inserted, and magnetically attracted and locked to the support plate portion; And a bottomed cylindrical magnet. A spindle comprising a base having substantially the same diameter as the central hole and having an axial length necessary or near the minimum for positioning the center of the substrate, and a peripheral portion having a smaller diameter than the central hole. Mask device for manufacturing plate-shaped recording media. 2. The different diameter hollow spindle, wherein the peripheral portion comprises a first cylindrical portion having a diameter sufficiently smaller than the central hole, and the base portion comprises a second cylindrical portion having substantially the same diameter as the central hole. 2. The mask device for manufacturing a disc-shaped recording medium according to claim 1, wherein: 3. The different diameter hollow spindle comprises a frusto-conical portion in which the peripheral portion is reduced in diameter from the diameter of the center hole toward the tip, and the base portion is formed of a cylindrical portion having substantially the same diameter as the center hole. The mask device for manufacturing a disc-shaped recording medium according to claim 1, wherein