JP3824829B2 - Duplicating stamper peeling apparatus and replica stamper peeling method for optical disk manufacturing - Google Patents

Description

[0001]
[Industrial application fields]
The present invention relates to a replication stamper peeling apparatus for manufacturing an optical disc. A replication stamper peeling apparatus that peels a mother stamper backed by a reinforcing member from a master stamper backed by a reinforcing member is peeled from the master stamper. The deformation (distortion) and damage that occur during the peeling operation on the mother stamper can be minimized.
[0002]
BACKGROUND OF THE INVENTION
A replication stamper for manufacturing an optical disk of high-density media (for example, DVD) is manufactured by the procedure shown in FIG. An example of the outline of this manufacturing process is as follows.
First, a fine groove pattern for recording guide having a pitch of 0.74 μm was formed with a Lipton laser exposure machine on an ultra-thin layer of a positive resist material having a thickness of about 1000 Å formed on the surface of a clean polished glass having a thickness of 6 mm, After developing this, a Ni conductive film is formed thereon by sputtering or electroless plating. This is the production of the glass master.
A master stamper thin film is formed by electroforming a glass master in a nickel sulfamate plating bath. This is master electroforming.
Then, an aluminum plate (reinforcing member) having a thickness of 5 mm is bonded to the formed master stamper to perform backing reinforcement.
Next, the resist layer is removed from the surface of the master stamper that has been reinforced by backing, and after a release coating treatment, electrocasting is again performed on the surface in the plating bath to form a thin film of the master stamper. This is maza electroforming.
Backing is performed by bonding an aluminum plate (reinforcing member) having a thickness of 5 mm to the mother stamper thin film. This state is shown in FIG.
The mother stamper is duplicated by peeling the mother stamper (thin film) from the master stamper. A large number of mother stampers are duplicated from the master stamper and used in the next step, but the above-mentioned master stamper and mother stamper are peeled off when the master stamper and the mother stamper are rubbed together during the peeling. Various problems such as damage of the recording bit and loss of information accuracy occur.
The present invention relates to a peeling apparatus and a peeling method for a master stamper and a mother stamper, which are lined with the above reinforcing members.
[0003]
[Prior art]
An example of a peeling technique for preventing the recording bit from being damaged by rubbing between the master stamper and the mother stamper during the peeling is disclosed in, for example, Japanese Patent Laid-Open No. 8-235646. It is described in the publication.
The outline of the prior art described in the above publication is as shown in FIG. 12 and FIG.
A cylinder 4 is provided on a bracket 3 projecting laterally from the upper end of a column 2 erected on the upper surface of the gantry 1, and an upper clamp member 5 is provided on the lower end of a vertical piston rod of the cylinder. An annular magnet 7 and a contact surface 6 are provided on the horizontal lower surface of the upper clamp member 5. The outer diameter of the upper clamp member 5 is smaller than the outer diameter of the polymer of the master A and the stamper B.
On the other hand, a lower clamp member 9 is fixed coaxially with the upper clamp member on a fixed base 8 fixed to the upper surface of the gantry 1, and an annular magnet 11 and a mounting surface 10 are on the upper surface.
An oxidant film is formed on the surface of the master A, and further a stamper B is formed thereon by nickel plating, and a polymer with the stamper B is placed coaxially on the lower clamp member 9 with the master A down. The upper and lower stampers B and the master A are attracted and fixed by the annular magnets 7 and 11, respectively.
Next, since an oxide film as a peeling layer is interposed between the master A and the stamper B, both are easily peeled off, but the stamper B and the master A are forced vertically upward. If the two layers are separated from each other, an air layer is not interposed between the two polymer surfaces, and they are in close contact with each other in a vacuum state, so that a strong force is required. If the layers are forcibly separated, the master A and the stamper B are destroyed. End up. Therefore, since it is actually impossible to peel off in this way, the cutting edge of the knife F is inserted into the periphery of the superposed surface of the master A and the stamper B, and the periphery is peeled off so that the stamper B is removed from the master A. After making it easy to peel off (FIG. 13A), the cylinder 4 is driven and the upper clamp member 5 is slowly raised. Since this is a so-called single plate stamper B that is peeled off from the master A, when a knife F is inserted at a predetermined depth to the periphery of the polymerization, atmospheric pressure acts from there, and the overlapping surfaces of both naturally peel off. . Accordingly, the stamper B is slightly lifted from the master A and is separated from the master A without moving laterally with respect to the master A (FIG. 13B).
In the above prior art, the entire surface of the master A and the stamper B is separated from the master A by pulling the stamper B vertically upward from the master A after putting the edge of the knife F at the periphery of the overlapping surface of the master A and the stamper B. It is easy and easy.
[0004]
The master stamper 11 and the mother stamper 12 are reinforced by backing the aluminum reinforcing members 13 and 14, respectively. The separating force perpendicular to the overlapping surface is applied to the reinforcing members 13 and 14, so that the master stamper 11 and the mother stamper There is a duplicate stamper peeling device for separating the stamper 12 (see FIGS. 1 and 2). In this case, since the master stamper 11 and the mother stamper 12 are backed by the reinforcing members 13 and 14 except for the outer peripheral portion thereof, a knife is put on the outer peripheral end surface of the overlapping surface, and this portion is peeled off. However, since the backed portion is still in a vacuum state, the backed portion is not peeled off or separated until this time. For this reason, a knife is inserted into the outer peripheral portion of the superposed surface and peeled off, and then a wedge is inserted into the peeled peripheral edge, and the blade edge is further pushed about 1 mm from the outer periphery of the reinforcing member 14 to be reinforced by the reinforcing member 14. A part of the overlapped superposed surface is peeled, thereby inducing vacuum breakage of the superposed surface of the part reinforced by the reinforcing members 13 and 14, and the master stamper 11 and the mother stamper 12 are instantaneously peeled off. It is. Specifically, this peeling operation is performed in a mode as shown in FIG. 3, for example.
That is, a part of the overlapping peripheral edge (outer peripheral edge) of the master stamper 11 and the mother stamper 12 is peeled in advance with a cutter F, and then a wedge 31 is inserted and backed by the reinforcing members 13 and 14 by a micro feed screw mechanism. This is a method in which it is slowly fed radially inward from the outer peripheral edge of the reinforcing member 13 until a vacuum break of the overlapped surface of the part is induced, and this partly slowly peels off. The wedge 31 in this peeling apparatus is a single-edged wedge having a flat bottom surface in contact with the master stamper 11, and has a blade edge angle of about 30 degrees and a thickness of about 10 mm.
When the cutting edge of the wedge 31 is inserted into the overlapping peripheral edge of the master stamper 11 and the mother stamper 12, and the cutting edge is further pushed inward in the radial direction from the outer peripheral edge of the reinforcing member 14, the cutting edge locally moves the mother stamper 12. Proceed while forcibly pushing and bending upward. In this way, when the blade edge of the wedge 31 is pushed further inward in the radial direction from the outer peripheral edge of the reinforcing member 14, the overlapping surface of the portion reinforced by the reinforcing member 14 when the leading end of the peeling is advanced by a predetermined distance. A vacuum breakage (breakage of the vacuum state generated on the polymerization surface because the upper and lower master stampers 11 and the mother stamper 12 are strongly pulled in the vertical direction) is induced, and the master stamper 11 and the mother stamper 12 are exposed all over. Peel off. The local upward deformation of the mother stamper 12 caused by the insertion of the wedge 31 until the vacuum break is induced reaches about 100 μm, and because of this deformation, the deformation is about 50 μm even after separation (plastic deformation). May remain locally, and the outer periphery of the mother stamper is often damaged locally due to strong rubbing with the cutting edge of the wedge.
[0005]
By the way, in the inspection performed on the production line of high density media of 3 GB or more typified by the DVD family, which is frequently used in recent years, it is inevitable that the inspection time becomes longer as the recording capacity increases. From the viewpoint of productivity, it is required to reduce the inspection time to the inspection time of a conventional recording medium which is not high density. In order to reduce the inspection time of high density media of 3 GB or more to the conventional inspection time, a stamper (thickness 0.3 mm) for high density media having a diameter of 250 mm is rotated at an ultrahigh speed of 3500 rpm. Severe conditions will be imposed. For this reason, the stamper signal inspection device and defect inspection device for DVD family media rotate the stamper at an ultra-high speed of 3500 rpm. In this case, the peripheral speed of the outer periphery of the stamper having a diameter of 250 mm is 157 Km / Hr. As a result, if a large aerodynamic lift acts on the outer periphery of the stamper, and there are irregularities due to the above-mentioned residual deformation on the outer periphery of the stamper, the air resistance accompanying high-speed rotation increases, and the deformation further increases. Is done. When the amount of deformation of the stamper is large, the stamper is strongly blown by the air flow. As a result, the stamper itself may be damaged, and the inspection device may be damaged. In addition, since it is exposed to ultra-high-speed rotation, problems due to force and vibration due to centrifugal force imbalance due to minute eccentricity of the rotation center overlap with this, further promoting the occurrence of the accident.
Even if the deformation is not so great as to induce the above-mentioned accident, even if it is placed on the vacuum suction table of the inspection system and is attracted to the suction table surface with high flatness, the stamper If there is a certain amount of deformation, outside air enters between the suction table surface and the stamper through the gap for this deformation, so the suction vacuum level does not rise above 250 mHg, and therefore the entire stamper surface should be evenly adhered to the suction table surface. I can't. Increasing the source pressure for vacuuming to bring the stamper into close contact improves the degree of vacuum by finely compensating the deformation distribution of the stamper.However, when the stamper is rotated at a high speed for testing, the degree of vacuum is reduced again. It becomes stable and pulling lowers the vacuum level, making it impossible to operate. As described above, if the strain due to the stamper deformation (plastic deformation) is larger than a certain level, it is practically impossible to perform signal inspection and defect inspection by ultra high speed rotation.
[0006]
[Problems to be solved]
In order to avoid the above problem, it is necessary to suppress the deformation of the stamper in the above-described peeling process as much as possible and to reduce the residual deformation of the peeled stamper as much as possible.
The size of the residual deformation depends on the shape of the wedge that is inserted into the overlapping periphery of the master stamper and the mother stamper in order to induce a vacuum break, and the insertion depth of the wedge that is necessary to induce the vacuum break. Depends on.
Accordingly, the present invention provides a new replica stamper peeling apparatus including the shape of the wedge and a method for inserting the stamper at the periphery of the stamper so that the deformation of the outer periphery of the stamper by the wedge can be reduced as much as possible. The challenge is to devise.
[0007]
[Measures taken to solve the problem]
The means taken to solve the above problems is to apply a vertical separating force to the polymer of the master stamper and the mother stamper backed by the reinforcing member, and insert a sharp wedge around the polymer periphery to create a vacuum on the polymer surface. On the premise of a replica stamper peeling apparatus for optical disk production that induces destruction, the apparatus is constituted by the following (a) to (d).
(A) The wedge is a thin, sharp double-edged wedge;
(B) providing a wedge guide portion for guiding the wedge in the radial direction of the polymer;
(C) providing a wedge driving device for driving the wedge impactively;
(D) The wedge blade tip is inserted impactively inward in the radial direction by the wedge driving means by a stroke defined by the overlapping peripheral edge of the master stamper and the mother stamper.
[0008]
[Action]
The thickness of the wedge and the angle of the blade edge are the same as the wedge of the mother stamper when the blade edge is inserted to a depth that induces vacuum breakage of the overlapping surface of the portion backed by the reinforcing member of the master stamper and mother stamper. The blade edge angle is such that the local deformation of the peeled portion by the blade edge remains within the elastic deformation limit. However, the lower limit of the wedge thickness is a limit necessary to ensure the rigidity necessary for impacting insertion into the outer peripheral portion of the overlapping surface of the portion guided by the wedge guide portion and lined with the reinforcing member. .
Since the wedge inserted into the outer periphery of the master stamper and the mother stamper is a double-edged wedge, the vertical deformation applied to the overlapping periphery of the portion backed by the reinforcing member by the blade edge of this wedge is caused by the master stamper and the mother stamper. Therefore, the deformation of the mother stamper is reduced accordingly.
Since the wedge is thin and the cutting edges of both blades are sharp, the vector of the peeling force applied to the master stamper and the mother stamper by the cutting edge is substantially parallel to the surface of the stamper, and the peeling is in a shear mode. Made. Therefore, the polymerization peripheral edge between the master stamper and the mother stamper is peeled off with a relatively small force, the force for pushing the peeled surface of the mother stamper upward is small, and the deformation of the peeling portion of the mother stamper is small. Therefore, deformation of the master stamper and the mother stamper can be suppressed (see FIG. 4).
Further, the wedge guide part is guided to a predetermined depth required to induce vacuum breakage, and the sharp edges of the wedges are moved in the radial direction of the polymer of the master stamper and the mother stamper by the wedge driving means. Is inserted in the direction of the shock, and the vacuum break of the overlapped portion of the backing line is induced at that moment, and the master stamper and the mother stamper are peeled off entirely, but the penetration along the overlapped surface of this blade edge is shocking Therefore, the speed effect when peeling the polymerization peripheral edge of the master stamper and the mother stamper in the shear mode is large, and therefore, the peeling is performed with a relatively small force.
Therefore, by inserting the blade edge of the wedge, the upward displacement and the stress component applied to the superposed peripheral edge of the master stamper and the mother stamper are reduced, and the deformation of the mother stamper is reduced within the elastic range (plastic deformation occurs). Can be suppressed to a range not present).
Therefore, the residual deformation of the mother stamper due to the insertion of the wedge for inducing the vacuum break is reduced as much as possible.
In addition, the local plastic deformation of the outer periphery of the mother stamper as well as the master stamper is suppressed to a very small range, and since the wedge is double-edged and sharp, the resistance of penetration of the backed part into the outer periphery of the overlapping surface is reduced. The damage to the periphery of the stamper due to the wedge is therefore significantly reduced.
[0009]
Embodiment 1
Embodiment 1 is that the wedge has a thickness of 0.5 mm to 10 mm.
Embodiment 2
Embodiment 2 is that the angle of the edge of the wedge is set to 1 degree to 10 degrees.
[0010]
Embodiment 3
Embodiment 3 is that the cutting edge of the wedge is subjected to a surface treatment so that its surface hardness is equal to or lower than the Ni plating hardness.
[Action]
The surface treatment is coating or application of an appropriate material.
A part of the outer peripheral edge of the backed portion of the master stamper and mother stamper polymerized at the blade edge insertion portion of the wedge is peeled up and down while strongly rubbing against the blade edge surface, but the hardness of the blade edge surface is Ni plating hardness or less Therefore, the mother stamper formed by nickel plating is not damaged by rubbing with the wedge surface.
[0011]
Embodiment 4
Embodiment 4 is that the speed of the impact insertion of the wedge is set to 600 mm / second or more.
[Action]
A sufficient speed effect can be obtained when separating the polymerization peripheral edges of the backed portions of the master stamper and the mother stamper in the shearing peeling mode, and they can be peeled off with a small force. Therefore, it is possible to suppress as much as possible the stress component that causes deformation due to wedge insertion.
Note that even if the wedge insertion speed exceeds 1000 mm / sec, there is no particular difference in its intended effect, and the adverse effect of vibration due to impact is expected, so 1000 mm / sec is an approximate upper limit for practical use. .
Moreover, even if it is 300 m-400 mm / sec, the peeling speed effect is acquired, and if it is 200 mm / sec or more, there is some technical significance of impact-inserting a wedge.
[0012]
Embodiment 5
In Embodiment 5, the mutual eccentricity of the fixing centers of the backing reinforcement members of the master stamper and the mother stamper is adjusted to 5 μm or less, and the polymer of the master stamper and the mother stamper is placed concentrically on the table of the stamper peeling apparatus. Then, using the replica stamper peeling device for optical discs according to the above solution, the blade edge of the wedge is shockedly inserted into the polymer peripheral edge of the polymer of the master stamper and the mother stamper, and the polymerization surface of the master stamper and the mother stamper is This is a method for peeling off a replica stamper for manufacturing an optical disc, which induces vacuum break.
[Action]
The greater the eccentricity of the fixed center of each backing reinforcement member with respect to the master stamper and the mother stamper, the greater the lateral movement of the mother stamper with respect to the master stamper at the moment of separation, which causes separation of the recording groove patterns separated from each other. When touched, they are touched and injured, and the recorded information is likely to be damaged.
However, even in the master stamper and mother stamper for high density media of 3 GB or more represented by the DVD family, the mutual eccentricity of the fixing center of the backing reinforcement member of each of the master stamper and the mother stamper is adjusted to 5 μm or less. The recording groove pattern can be prevented from being damaged by peeling using the replica stamper peeling device according to the above solution.
In addition, the adverse effects of centrifugal force and vibration due to eccentricity when rotating at an ultra high speed by the inspection apparatus are reduced as much as possible, and the inspection operation can be performed smoothly and reliably.
[0013]
Embodiment 6
In the sixth embodiment, the mother stamper supporting member fixed to the backing reinforcement member of the mother stamper is urged upward by the accumulating means, and at the same time as the vacuum break caused by the insertion of the wedge, the urging force by the accumulating means is instantaneously applied. That is, the mother stamper is moved upward by a predetermined stroke.
[Action]
Since the mother stamper is moved upward by a predetermined stroke by the support member instantaneously at the same time as the vacuum break due to the wedge insertion, both the master stamper and the mother stamper do not come into contact with each other again. It is prevented that the recording grooves of both stampers are damaged by the recontact.
[0014]
Embodiment 7
Embodiment 7 is that, in Embodiment 6, the means for defining upward movement of the mother stamper support member to a predetermined stroke is a stopper having a buffer function.
[Action]
When the mother stamper support member is instantaneously moved upward by the urging force of the power storage means and collides with the stopper, it is buffered by the stopper. Collision and damage is effectively avoided.
[0015]
[Embodiment 8]
In the eighth embodiment, the stopper of the seventh embodiment is a stopper with damping means using a friction damper and an air damper.
[Action]
Since the damping function is added to the stopper by a simple damping means such as a friction damper or an air damper, vibration is absorbed, and the above-described re-collision preventing effect by the stopper according to the seventh embodiment is more reliably achieved.
[0016]
Embodiment
Next, embodiments will be described with reference to the drawings.
The backing reinforcing members 13 and 14 that adhere to and reinforce the master stamper 11 and the mother stamper 12 have no particular problem as long as the flatness of the bonding surface is 20 μm or less. The flatness of 20 μm is a flat finishing accuracy that can be sufficiently obtained by a normal grinding process using a lathe method or a grinding method for an aluminum plate having a thickness of 5 mm and a diameter of 250 mm. Therefore, the flatness of the bonding surface of the reinforcing members 13 and 14 is In consideration of the processing cost, the flatness may be 20 μm and the surface roughness Ra2S may be sufficient.
[0017]
FIG. 5 shows an isolating device for separating the master stamper and the mother stamper reinforced with the backing reinforcing member having the above-described plane processing accuracy.
A support block 53 is supported on an upper portion of a support column 52 that is erected vertically on one end of a base 51 of the replica stamper peeling apparatus, and the accumulated force is such that the lower surface of the support block 53 is loosely fitted to the support column. It is supported by a coil spring 54 for use. One end of a mother stamper support member 56 is pivotally supported by a horizontal pivot pin 55 of the support block 53 so as to project horizontally in the lateral direction. One end of the mother stamper support member 56 is pivotally supported by a pivot pin 55 so as to be swingable upward from the horizontal state in order to prevent elastic vibration in the vertical direction. Therefore, the mother stamper support member 56 is It can be swung upward from the horizontal position with the pivot pin 55 as a support shaft.
Further, a stopper 58 having a buffering function is provided at the tip of the bracket 57 at the upper end of the support column 52, thereby defining the upward movement stroke of the support block 53. This stopper 58 has a simple buffer means using a buffer rubber, and can absorb and relieve an impact when stopping the upward movement of the support block 53.
[0018]
Further, a horizontal table 60 is provided on the upper surface of the base 59 of the base 51. A central boss (column boss having a diameter of 8 mm, FIG. 5) of the table 60 is provided with a master stamper and a mother stamper (information recording range diameter 120 mm). The center holes of the backed reinforcing member 13 (diameter 176 mm) and reinforcing member 14 (diameter 170 mm) are fitted and held on the table 60 coaxially.
On the other hand, there is a wedge guide portion 62 formed by a guide slit on a guide column 61 that stands vertically at multiple ends of the base 51, and the wedge guide portion 62 can slide the wedge W horizontally in the radial direction of the table 60. I am guiding you. The wedge W is impacted and pushed at a speed of 700 mm / second toward the master stamper 11 and the mother stamper 12 by the wedge driving device D using an air hammer, and the cutting edge is lined with the master stamper 11 and the mother stamper 12. About 1 mm is shockedly inserted into the polymerization periphery of the part.
Note that the wedge insertion speed of 700 mm / second is an impact speed that is lightly hit with a hammer and is not a particularly high speed.
[0019]
With the master stamper and the mother stamper placed on the upper surface of the table 60 together with the reinforcing members 13 and 14 and fixed with fixing bolts (not shown), the support block 53 is pushed down against the accumulator coil spring 54 and the mother stamper support member 56 is aligned with the center (by fitting the positioning boss of the mother stamper support member 56 and the center hole of the reinforcing member 14) to abut against the reinforcing member 14, and a mounting bolt is attached to the hole 56a of the mother stamper supporting member 56. The mother stamper supporting member 56 is fixed to the reinforcing member 14 by inserting it into the screw hole 14 a on the upper surface of the reinforcing member 14.
At this time, the coil spring 54 is compressed by a predetermined amount and stored, and this force urges the reinforcing block 14 of the mother stamper 12 upward through the support block 53 and the mother stamper support member 56 with the stored force. The magnitude of the accumulated force of the coil spring 54 is 5 kg in this embodiment, but the tightening bolt 64 of the adjustment block 63 slidably fitted to the support column 52 is loosened, and the position of the adjustment block 63 is moved up and down. It is adjusted by moving.
The above procedure of fixing the adjustment block 63 at a predetermined position, pushing down the support block 53 against the coil spring 54 and accumulating force, and screwing the mother stamper support member 56 to the reinforcing member 14 in this state is the principle. This is an explanatory procedure, and it is not easy to screw the mother stamper support member 56 to the reinforcing member 14 while resisting the urging force by the coil spring 54.
That is, as shown in FIG. 5B, the adjustment block 63a is slidably fitted up and down on the support column 52, and a C-shaped sleeve 70 is detachably fitted to the support column 52 from the side. The upper end supports the lower surface of the adjustment block 63a. The freeb 70 is removed to the side, the adjustment block 63a is dropped, and the coil spring 54 is disabled. As a result, the support block 53 and the mother stamper support member 56 are free with respect to the coil spring 54. In this state, the mother stamper support member 56 is screwed to the reinforcing member 14, and then the adjustment block 63a is pushed up against the coil spring 54, and a sleeve 70 having a predetermined height is attached from the side to support the adjustment block 63a. . Since the position of the adjustment block 63a is determined by the height of the sleeve 70, the urging force by the coil spring 54 is constant. And the said urging | biasing force is adjusted suitably by changing to the sleeve 70 from which height differs.
Note that since the operating stroke of the power storage means is very small, an air spring, an elastic rubber, a leaf spring, a disc spring, or the like can be used in addition to the coil spring.
In addition, the theoretical minimum of the height at which the support block 53 and the mother stamper support member 56 should be pushed up by the power storage means is equal to or greater than the depth of the recording groove (about 0.1 mm). The upward movement stroke of the block 53 (the restriction stroke by the stopper 58) is 10 mm.
[0020]
As described above, in the state where the predetermined separating and urging force by the coil spring 54 is applied between the upper and lower reinforcing members 13 and 14, the cutting edge of the wedge W is moved to the master stamper 11 and the mother stamper 12 by the wedge driving device (air hammer) D. Of the master stamper 11 and the mother stamper 12 by the separation urging force at the moment when the cutting edge reaches a depth (about 1 mm) that can induce vacuum breakage. The entire polymerization surface is peeled off in an instant, the master stamper 11 and the mother stamper 12 are separated from each other, and the mother stamper 12 is pulled up by the mother stamper support member 56. This pulling stroke is regulated by a stopper 58 for the support block 53. The mother stamper support member 56 repels at the moment when the master stamper 11 and the mother stamper 12 are peeled off. However, since the support block 53 collides with the stopper 58 and its upward movement is stopped, and the impact at that time is absorbed and alleviated by the buffering function of the stopper 58, the vertical vibration of the mother stamper support member 56 is suppressed. Therefore, it is avoided that the separated mother stamper 12 vibrates up and down by reaction and comes into contact with the master stamper again.
As a driving source of the wedge driving device, a spring force and an electromagnetic force can be used in addition to an aerodynamic force.
[0021]
The stopper 58 has a simple buffer function by elastic rubber, and a simple friction damper (attenuating means by friction hysteresis) or a simple air damper (attenuating means by fluid hysteresis) is added thereto. Thus, the vertical vibration of the mother stamper can be reliably absorbed, and the buffering effect of the stopper can be further improved. In this case, it is effective to connect the stopper to the mother stamper support member 56 and to move up and down following the mother stamper support member 56 with a predetermined stroke.
Further, when the mother stamper support member 56 is bent by the urging force of the coil spring 54, the mother stamper support member 56 vibrates in the vertical direction due to the elastic recovery of the bending. It is desirable to have a high rigidity against the bending moment.
[0022]
The wedge W in this embodiment is a normal tool steel, its thickness is 1.5 mm, and its blade edge angle is 4 degrees. The thickness of the wedge W must be sufficient to ensure the required strength and rigidity. Even if the thickness is less than 1.5 m, there is not much difference in the expected effect.
The relationship between the blade tip angle of the wedge W and the deformation amount of the mother stamper due to the insertion of the wedge is as shown in FIG. 9, and the point A in the figure is the limit where the deformation amount of the mother stamper 11 exceeds the elastic range. Accordingly, even if the blade edge angle of the wedge W is too small, the effect is not different. Therefore, the range of 3 to 4 degrees is appropriate in consideration of practical aspects such as cutting of the blade edge.
In this embodiment, a Teflon coat is applied to the blade surface that rubs against the peeling surface of the master stamper and the mother stamper to prevent the peeling surface of the master stamper and the mother stamper from rubbing against the blade surface of the wedge W and being damaged. ing. By applying Teflon coating to the blade surface in this way, shocking wedge insertion and stress release due to the release of the stress are suppressed by the elasticity of the Teflon coating, and damage to the mother stamper peeling surface due to this vibration is prevented. The
Furthermore, the width of the wedge W is 15 mm. As for the width of the wedge, it is desirable that the wedge is narrow to some extent in view of the original function of the wedge W. However, the wedge guide portion 62 accurately and stably guides the wedge in the radial direction of the polymer of the master stamper and the mother stamper. For this purpose, a certain amount of width is required. Considering these facts comprehensively and from the results of experiments, the width of the wedge is preferably 13 to 18 mm. Further, the tip of the wedge blade tip has an arc shape as shown in FIG. 14 in order to prevent the peeling surface of the mother stamper from being damaged by the edge.
[0023]
The wedge W is pushed out relatively slowly until the tip reaches the outer peripheral edge (position of diameter 170 mm) of the portion backed by the reinforcing member 14 (diameter 170 mm) of the mother stamper 12, and the tip is backed by the reinforcing member 14. When it reaches the outer peripheral edge of the portion, it is impacted by a wedge drive device (air hammer) D from there. This driving stroke is regulated by a stopper so that the penetration depth at the tip of the blade edge does not exceed a necessary limit (for example, approximately 1 mm).
[0024]
In an ideal state in which the fixing centers of the reinforcing members 13 and 14 to the master stamper 11 and the mother stamper 12 in the state of being mounted on the table 60 are completely coincident with each other, the mother stamper 12 is shown in FIG. As shown in FIG. However, since the fixing centers of the reinforcing members 13 and 14 are actually eccentric from each other (see FIG. 10), they are separated upward with slight lateral movement. If the amount of eccentricity is 5 μm or less, it is avoided that the recording groove of the mother stamper 12 touches the recording groove of the master stamper 11 during separation.
Incidentally, when the mother stamper 12 separated by the replication stamper peeling device of the above embodiment is mounted on the suction table of the inspection apparatus, a suction pressure of 550 mHg is raised, and the entire surface of the mother stamper 12 is uniformly sucked on the suction table of the inspection apparatus. It was confirmed that recording inspection and defect inspection could be performed without any trouble at an ultra-high speed of 3500 rpm.
[0025]
【effect】
Regarding the peeling device between the master stamper and the mother stamper, a wedge that is inserted into the overlapping peripheral edge of the backed portion of the master stamper and the mother stamper and locally peels this is a thin, sharp double-edged wedge. By inserting the cutting edge in a stroke defined by the above-mentioned superposed peripheral edge, the vacuum breakage of the superposed surface of the backed portion is induced, so that the force to peel off the superposed peripheral edge is the upper surface of the mother stamper. The master stamper is less deformed upward by inserting the wedge, and the peripheral edge of the mother stamper is rubbed by the friction between the blade surface of the wedge and the peeled surface of the mother stamper. Damage is avoided as much as possible.
As described above, since local residual deformation and damage on the outer peripheral portion of the peeled mother stamper are avoided as much as possible, the entire surface of the mother stamper is evenly sucked on the suction table of the inspection apparatus.
Therefore, it is possible to reliably and efficiently perform recording inspection and defect inspection by ultra-high speed rotation of 3500 rpm.
As described above, since a replication stamper free from local deformation and damage can be easily created, the inspection time can be shortened and a remarkable economic effect can be expected.
[0026]
In addition, a part of the polymerization peripheral edge of the backed portion of the master stamper and the mother stamper is peeled up and down while rubbing against the blade edge surface of the wedge, but the hardness of the blade edge surface is reduced to Ni plating hardness or less by the surface treatment. Therefore, the effect of preventing damage due to rubbing of the release surface of the master stamper formed by nickel plating with the wedge blade surface is further improved. Further, damage to the release film of the master stamper due to the wedge blade surface is avoided, and the mother stamper is duplicated stably by the master stamper.
[0027]
Furthermore, since the speed of the impact insertion of the wedge is set to 600 mm / second or more, the speed effect when the polymerization peripheral edge of the master stamper and the mother stamper is separated in the shear peeling mode is sufficiently utilized. It can be peeled off by force, and it is possible to reduce the upward transition and stress components that cause deformation at the peripheral edge of the mother stamper by inserting the wedge.
[0028]
Furthermore, the greater the mutual eccentricity of the fixed center of each backing reinforcement member with respect to the master stamper and the mother stamper, the greater the lateral movement of the mother stamper with respect to the master stamper at the moment of separation, and therefore the recording groove at the moment of separation. There is a high possibility that the pattern will be touched and damaged, and the recorded information will be damaged. By adjusting the mutual eccentricity of the fixed center of the backing reinforcement members of the master stamper and mother stamper to 5 μm or less, Even a master stamper and a mother stamper for high density media of 3 GB or more represented can prevent damage to the recording groove pattern, and further, the centrifugal amount and vibration due to the eccentricity are minimized. In combination with the above-mentioned local deformation and damage prevention of the mother stamper, Efficiently and stably by ultra high speed rotation of severity, and can be safely inspected.
[Brief description of the drawings]
FIG. 1 is a perspective view of a polymer of a master stamper and a mother stamper.
FIG. 2 is a perspective view showing a state in which a master stamper and a mother stamper are separated.
FIG. 3 is a schematic view of a conventional replication stamper peeling method using a wedge.
FIG. 4 is a schematic view of a replication stamper peeling method of the present invention.
FIG. 5 is a longitudinal sectional view of a replication stamper peeling apparatus according to an embodiment.
FIG. 6 is a schematic diagram of a normal separation mode of a master stamper and a mother stamper.
FIG. 7 is a schematic diagram of a trouble mode in which a recording groove contacts when the master stamper and the mother stamper are separated.
FIG. 8 is a schematic diagram of a trouble mode in which the recording grooves of the master stamper and the mother stamper come into contact again.
FIG. 9 is a diagram showing the correlation between the edge angle of the wedge and the local deformation of the stamper.
FIG. 10 is a schematic diagram showing a shift of a fixing center between a reinforcing member of a master stamper and a reinforcing member of a mother stamper.
FIG. 11 is a flowchart of a stamper manufacturing process.
FIG. 12 is a schematic perspective view of a conventional replication stamper peeling apparatus.
13A is a perspective view of a main part of the duplicate stamper peeling apparatus of FIG. 12, and FIG. 13B is a perspective view showing a stamper separation process by the duplicate stamper peeling apparatus.
14 is a plan view of the cutting edge of the wedge W. FIG.
[Explanation of symbols]
11: Master stamper
12: Mother stamper
13: Reinforcement member for master stamper
14: Mother stamper reinforcement member
14a: Screw hole
31: Conventional single-edged wedge
51: The base of the duplicate clamper peeling device
52: Prop
53: Support block
54: Coil spring
55: Pivot pin
56: Mother stamper support member
56a: hole
57: Bracket
58: Stopper
59: Base
60: Table
61: Guide support
62: Wedge guide part
63, 63a: Adjustment block
64: Tightening bolt
70: Sleeve
D: Wedge drive device
F: Knife
W: Double-edged wedge
BO: Central boss

Claims (8)

In a stamper peeling apparatus for manufacturing an optical disk, in which a wedge is inserted into a polymer of a master stamper and a mother stamper to peel off the polymer,
A double-edged wedge with an angle of the blade edge of 1 to 10 degrees;
A wedge guide for guiding the wedge in the radial direction of the polymer;
Wedge driving means for inserting the wedge into the periphery of the polymer at an insertion speed of 200 to 1000 mm / sec;
A stamper peeling apparatus for manufacturing an optical disc comprising: The replication stamper peeling apparatus for manufacturing an optical disk according to claim 1, wherein the wedge has a thickness of 0.5 mm to 10 mm. 2. The replica stamper peeling apparatus for manufacturing an optical disk according to claim 1, wherein the cutting edge of the wedge is subjected to a surface treatment so that the surface hardness is equal to or lower than the Ni plating hardness. The stamper support member fixed to the reinforcing member backed by the mother stamper is urged upward by the force storage means, and at the same time as the vacuum break due to the insertion of the wedge, the mother stamper is instantaneously pressed by the force of the force storage means. 2. The duplication stamper peeling apparatus for manufacturing an optical disk according to claim 1, wherein the apparatus is moved upward by a predetermined stroke. 5. The duplication stamper peeling apparatus for manufacturing an optical disk according to claim 4 , wherein the power storage means is a coil spring or an air spring. 5. The duplication stamper peeling apparatus for manufacturing an optical disk according to claim 4 , wherein the means for regulating the upward movement of the reinforcing member of the mother stamper to the predetermined stroke is a stopper having a buffer function. 7. The duplication stamper peeling apparatus for manufacturing an optical disk according to claim 6 , wherein the stopper having the buffer function is a stopper with a shock absorber made of elastic rubber. 7. The duplication stamper peeling apparatus for manufacturing an optical disk according to claim 6 , wherein the stopper having a buffer function is a stopper with a damping means by a friction damper and an air damper.

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