JP2015119104A - Fine pattern forming method and fine pattern forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fine pattern forming method capable of performing a roll imprinting with high transfer accuracy while increasing the transfer molding speed to enhance the productivity.SOLUTION: The fine pattern forming method includes the steps of: pressing a UV hardening resin 20 placed on the surface of a transparent base plate 12 with a pressure roll 13 which is disposed on a sheet-like mold 11 for forming a fine pattern 23b and is moved in a predetermined pressure roll moving direction; and applying UV light 25 onto a part of the UV hardening resin 20 under the sheet-like mold 11 from the side opposite to the surface of the transparent base plate 12 placed with the UV hardening resin 20 while moving the UV irradiator 16 applying the UV light 25 in the pressure roll moving direction.

Description

  The present invention relates to a fine pattern forming method and a fine pattern forming apparatus using, for example, a UV curable roller nanoimprint technique using a UV curable resin.

  In recent years, in optical parts used in products such as displays and lighting, reflection or diffraction of light is controlled by forming fine patterns of nanometer (nm) order to micron (μm) order that exhibit special optical characteristics. Therefore, it is desired to realize a device that exhibits a new function that has not existed before.

  A nanoimprint technique is used as a method of manufacturing an optical component having such a fine pattern.

  Nanoimprint technology is a technique in which a fine pattern is transferred to the surface of a resin by pressing the mold against the resin applied to the substrate surface using a mold that has been designed on the surface in advance. This is a molding method.

  As a method for transferring a fine pattern, a thermal imprint method in which a thermosetting resin is applied to a resin to be applied to the substrate surface, and a UV (Ultraviolet) curable resin are used for transfer while irradiating UV light. And UV imprint method.

  Regarding the thermal imprinting method, the selectivity of the material is wide, but since the viscosity of the material is high, the transfer rate with respect to the mold is not so high, and it takes time to raise and lower the temperature, so that the throughput is not so high.

  For the UV imprint method, the material selectivity is not wide, but since the viscosity of the material is generally low, the transfer rate to the mold is high. And since it hardens | cures by irradiating an ultraviolet-ray, a throughput is high.

  Which of the thermal imprinting method and the UV imprinting method is desired to be employed differs depending on the application device, but the UV imprinting method is considered suitable as a mass production method when there is no problem caused by the material.

  Therefore, a conventional UV nanoimprint method will be described with reference to FIG.

  Here, FIGS. 7A to 7D are schematic process explanatory views (1 to 4) of the conventional UV nanoimprint method.

  First, as shown in FIG. 7A, a mold 61 on which a fine pattern is formed is prepared in advance.

  Then, as shown in FIG. 7B, the mold 61 is pressed against the UV curable resin 63 applied on the substrate 62, and the UV curable resin 63 is filled in the fine pattern on the surface of the mold 61.

  Next, as shown in FIG. 7C, the UV light 64 is irradiated while the mold 61 is pressed to cure the UV curable resin 63.

  Thereafter, as shown in FIG. 7D, the mold 61 is released from the substrate 62, and a fine pattern is transferred and formed on the substrate 62.

  In such a UV nanoimprint method, since it is necessary to irradiate the UV curable resin 63 with the UV light 64, generally, the mold 61 is made of a material that transmits the UV light 64, such as quartz, Either a method of irradiating the UV light 64 from the 61 side or a method of irradiating the UV light 64 from the substrate 62 side using a material that transmits the UV light 64 to the substrate 62 is used.

  As a transfer molding method, generally, a flat plate-shaped mold 61 is pressed against a substrate 62 coated with a UV curable resin 63 in parallel and then irradiated with UV light 64 to release the mold 61 upward. There is a way to do it.

  In such a method, when a large-area molding is performed, not only a press pressure of several tens of tons level is required, but also minute air bubbles may remain inside when pressed. The entire part must be covered with a chamber and vacuum forming must be performed to reduce the pressure.

  As a transfer molding method that can reduce the possibility of such air remaining and does not require vacuum forming, there is a roll imprint method (for example, see Patent Document 1).

  A conventional roll imprint method will be described with reference to FIG.

  FIG. 8 is a schematic process explanatory diagram of a conventional roll imprint method.

  A mold 52 on which a fine pattern is formed and a transfer film 53 to which a UV curable resin is applied are placed between a cylindrical front roller 51 and a substrate 54, and transfer molding is performed while sandwiching them. Alternatively, a flexible mold 52 is wound around the surface of the cylindrical front roller 51, and transfer molding is performed while pressing the flexible mold 52 against the film to be transferred 53 placed on the substrate 54.

  The back roller 56 is a means for equalizing the contact pressure between the front roller 51 and the substrate 54 in the longitudinal direction of the front roller 51. When forming a fine pattern using the large area substrate 54, the front roller 51 It is possible to suppress variations in contact pressure that are likely to occur due to the increase in length.

  The transfer film 53 is cured by irradiating UV light 57 near the contact point between the front roller 51 and the transfer film 53 from an oblique rear side of the front roller 51 by a UV irradiator 55 installed behind the front roller 51. Done in

  Since the mold 52 is sequentially pressed against the transfer film 53 on the line in the roll width direction by roll feeding, air is hardly trapped in a portion between the mold 52 and the transfer film 53. Since the contact region between the mold 52 and the film to be transferred 53 is linear, the pressing pressure can be reduced.

JP 2007-289999 A

  However, in the above-described conventional roll imprint method, UV light is irradiated from the diagonally rear side of the front roller 51.

  For this reason, it is difficult to irradiate the UV light to the contact point between the mold 52 and the film to be transferred 53 where the curing of the UV curable resin is likely to proceed, so it is difficult to increase the transfer molding speed that affects the productivity. At the same time, the transfer accuracy is not necessarily high enough.

  An object of the present invention is to provide a fine pattern forming method and a fine pattern forming apparatus capable of realizing high productivity and transfer accuracy in consideration of the conventional problems described above.

The first aspect of the present invention is a sheet-shaped long mold for forming a fine pattern on the UV curable resin, which is disposed on the UV curable resin placed on the surface of the transparent substrate. A pressing step for pressing using a pressing roll that is arranged on the top and moved in a predetermined pressing roll moving direction;
While moving a UV light source for irradiating UV light in the direction of movement of the pressing roll, the UV light is applied to the UV curable resin portion under the pressed sheet-shaped long mold portion, UV light irradiation step of irradiating from the opposite side of the surface of the transparent substrate on which the UV curable resin is placed;
It is a fine pattern formation method characterized by comprising.

2nd this invention hold | maintains the both ends of the said sheet-like long mold using a mold holding roll, and moves the said press roll to the said press roll moving direction, The said mold holding roll is made into the said transparent substrate. A mold holding roll moving step for moving in a direction perpendicular to the surface,
The mold holding roll is moved so that the angle between the surface of the transparent substrate and the sheet-like long mold does not fluctuate despite the pressing roll being moved, It is the fine pattern formation method of 1st this invention.

  The third aspect of the present invention is a UV light source swing that swings the UV light source in a direction parallel to the surface of the transparent substrate and perpendicular to the press roll moving direction while moving the UV light source in the pressing roll moving direction. It is the fine pattern formation method of the 1st or 2nd this invention characterized by including a process.

  The fourth aspect of the present invention is the fine pattern forming method according to any one of the first to third aspects of the present invention, wherein the spread angle of the irradiated UV light is 5 degrees or less.

According to a fifth aspect of the present invention, a plurality of the sheet-like long molds are provided in a direction parallel to the surface of the transparent substrate and perpendicular to the pressing roll moving direction,
A plurality of the pressing rolls are provided so as to correspond to each of the plurality of sheet-like long molds provided,
Among the plurality of pressing rolls provided, the pressing is performed so that the interval between the pressing rolls provided so as to correspond to the adjacent sheet-shaped long molds is maintained at a predetermined interval or more. The method for forming a fine pattern according to any one of the first to fourth aspects, wherein the roll is moved in the direction of movement of the pressing roll.

In the sixth aspect of the present invention, a plurality of the sheet-like long molds are provided in a direction parallel to the surface of the transparent substrate and perpendicular to the pressing roll moving direction,
In the method for forming a fine pattern according to the first aspect of the present invention, only one pressing roll is provided.

  The seventh aspect of the present invention is the fine pattern forming method according to the sixth aspect of the present invention, wherein the hardness of the surface of the pressing roll decreases from the center to the end in the longitudinal direction.

  The eighth aspect of the present invention is the fine pattern forming method according to the sixth aspect of the present invention, wherein the diameter of the core shaft of the pressing roll decreases from the center to the end in the longitudinal direction.

The ninth aspect of the present invention is a sheet-shaped long mold for forming a fine pattern on the UV curable resin, which is disposed on the UV curable resin placed on the surface of the transparent substrate,
A pressing roll disposed on the sheet-like long mold and moved in a predetermined pressing roll moving direction; and
A UV light source for irradiating UV light, which is moved in the pressing roll moving direction;
With
The pressing roll presses the sheet-shaped long mold placed thereon against the UV curable resin placed on the surface of the transparent substrate while being moved in the predetermined pressing roll moving direction. ,
While the UV light source is moved in the pressing roll moving direction, the UV light is applied to the UV curable resin portion under the pressed sheet-like long mold portion, and the UV curing is performed. The fine pattern forming apparatus irradiates from the opposite side of the surface of the transparent substrate on which the resin is placed.

  According to the present invention, a fine pattern forming method and a fine pattern forming apparatus capable of realizing high productivity and transfer accuracy can be provided.

1 is a schematic perspective view of a fine pattern forming apparatus according to a first embodiment of the present invention. 1 is a schematic cross-sectional view of a fine pattern forming apparatus according to a first embodiment of the present invention. (A) Schematic sectional view of the fine pattern forming apparatus according to the first embodiment of the present invention (part 1), (b) Schematic sectional view of the fine pattern forming apparatus according to the first embodiment of the present invention (part 2), (c) ) Schematic sectional view of the fine pattern forming apparatus according to the first embodiment of the present invention (No. 3) Schematic perspective view of a fine pattern forming apparatus according to Embodiment 2 of the present invention. Schematic perspective view of a fine pattern forming apparatus according to Embodiment 3 of the present invention. (A) Schematic sectional view of the pressing roll of the fine pattern forming apparatus of the third embodiment of the present invention (No. 1), (b) Schematic sectional view of the pressing roll of the fine pattern forming apparatus of the third embodiment of the present invention ( 2) (A) Schematic process explanatory diagram of the conventional UV nanoimprint construction method (Part 1), (b) Schematic process explanatory diagram of the conventional UV nanoimprint construction method (Part 2), (c) Schematic process explanatory diagram of the conventional UV nanoimprint construction method ( Part 3), (d) Schematic process explanatory diagram of conventional UV nanoimprint method (Part 4) Schematic process explanatory diagram of conventional roll imprint method

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

(Embodiment 1)
First, the configuration of the fine pattern forming apparatus of the present embodiment will be described with reference to FIGS.

  FIG. 1 is a schematic perspective view of the fine pattern forming apparatus according to the first embodiment of the present invention, and FIG. 2 is a schematic sectional view of the fine pattern forming apparatus according to the first embodiment of the present invention.

  The fine pattern forming apparatus of the present embodiment includes a sheet-shaped mold 11, a pressing roll 13, a substrate insertion side holding roll 15 and a substrate discharge side holding roll 14, a UV irradiator 16, and a coating unit 17. .

  The sheet-shaped mold 11 is a flexible mold in which a plurality of fine patterns 23a (see FIG. 2) are formed in a line at equal intervals.

  The pressing roll 13 is a roll that moves on the transparent substrate 12 to the substrate insertion side while pressing the fine pattern 23 a (see FIG. 2) of the sheet-shaped mold 11 against the transparent substrate 12.

  The substrate insertion side holding roll 15 and the substrate discharge side holding roll 14 are rolls that can fix both ends of the sheet-shaped mold 11 while maintaining a predetermined tension.

  The UV irradiator 16 is an irradiator that irradiates the contact point between the sheet mold 11 and the transparent substrate 12 with UV light 25 while moving in the same direction as the pressing roll 13 at the same speed.

  The application unit 17 is a unit that applies the UV curable resin 20 to the transparent substrate 12. Although only one coating unit 17 is shown for each sheet-shaped mold 11 in FIG. 1 and the like, a plurality of coating units 17 may of course be provided when the width of the sheet-shaped mold 11 is wide.

  As will be described in detail later, the holding roll control unit 18 (see FIG. 2) is a unit that moves the substrate insertion side holding roll 15 and the substrate discharge side holding roll 14 in the vertical direction according to the position of the pressing roll 13. . Of course, recognition of the position of the pressing roll 13 by the holding roll control unit 18 may be performed directly using (1) a sensor for detecting the position of the pressing roll 13 or (2) pressing. It may be performed indirectly by calculation based on a predetermined relationship between the feed speed of the roll 13 and time.

  The transparent substrate 12 is an example of the transparent substrate of the present invention, the sheet mold 11 is an example of the sheet-like long mold of the present invention, the pressing roll 13 is an example of the pressing roll of the present invention, and UV irradiation. The vessel 16 is an example of the UV light source of the present invention.

  Moreover, the board | substrate insertion side holding roll 15 and the board | substrate discharge | emission side holding roll 14 are examples of the mold holding roll of this invention.

  Next, the operation of the fine pattern forming apparatus of the present embodiment will be described with reference mainly to FIG.

  An example of the fine pattern forming method will also be described while explaining the operation of the fine pattern forming apparatus of the present embodiment (the same applies to other embodiments).

  The transparent substrate 12 on which the UV curable resin 20 is applied is fixed to a predetermined position on the quartz base 21 that is a support base that transmits the UV light 25. Before and after the fixed transparent substrate 12, a running plate 22 having the same thickness as the transparent substrate 12 is installed.

  The pressing roll 13 is located at the position of the run-up plate 22 installed on the substrate discharge side of the quartz base 21 from above the sheet-shaped mold 11 fixed at both ends by the substrate discharge side holding roll 14 and the substrate insertion side holding roll 15. Lower and apply a predetermined pressure.

  The pressing roll 13 moves on the transparent substrate 12 while applying a predetermined pressure to the sheet-like mold 11 on which the fine pattern 23a is formed.

  At this time, the UV irradiator 16 almost immediately below the contact point between the sheet-shaped mold 11 and the transparent substrate 12 moves in synchronization with the pressing roll 13 while irradiating the UV light 25 through the light shielding mask 24.

  The substrate discharge side holding roll 14 and the substrate insertion side holding roll 15 repeatedly move up and down in conjunction with the movement of the pressing roll 13 (see FIG. 2).

  More specifically, the substrate discharge side holding roll 14 and the substrate insertion side holding roll 15 each have a predetermined angle between the sheet-shaped mold 11 and the transparent substrate 12 during pressure application, as will be described in detail later. It is moved up and down to be an angle.

  The UV curable resin 20 on the transparent substrate 12 filled in the dents on the surface of the fine pattern 23a is released from the sheet mold 11 after being cured.

  The pressure roll 13 that has reached the run-up plate 22 on the substrate insertion side rises after releasing the pressure, leaves the sheet-shaped mold 11, returns to the position on the substrate discharge side, and waits.

  A plurality of fine patterns 23b are transferred and formed on the transparent substrate 12 having a large area by repeating such operations.

  In order to increase the area of the transparent substrate 12 or to obtain a large number of fine patterns 23b, a plurality of pairs of sheet-shaped molds 11 and pressing rolls 13 are arranged in parallel in the width direction of the transparent substrate 12, and the sheet-shaped molds 11 are long. It can cope easily by scaling.

  Large-area imprint molds are generally produced by a transfer molding process in which small-sized reversal-shaped molds are transferred from an expensive small-size original plate, joined together, and then transferred again to a large area. .

  For this reason, not only often a great deal of cost and time is required, but if there is a slight distortion, warp or step, wrinkles and voids are likely to occur when the substrate is pressed against the substrate by the pressure roll, and transfer defects increase. Such a fear is further increased when the length of the pressing roll is increased.

  In the present embodiment, a sheet-like mold 11 having a shape obtained by dividing a large-area imprint mold in the width direction of the transparent substrate 12 is used.

  Accordingly, since the number of processes corresponding to the above-described transfer molding process is small, the cost of the sheet-shaped mold 11 can be kept low, and the variation in the pressing force of the pressing roll 13 is small for shortening the pressing roll transfer. Large area imprint with few defects is possible.

  Of course, two pairs of sheet-shaped molds 11 do not necessarily have to be used, and if that is sufficient, only one sheet-shaped mold 11 may be used.

  In the conventional roll imprint method (see FIG. 8) described above, in order to collectively form the transfer film 53 having a large area fine pattern or a plurality of fine patterns arranged on the substrate 54. Requires a large-area mold 52 and is likely to increase costs.

  Of course, it is not impossible to correct the variation in contact pressure due to the increase in the length of the front roller 51 with the increase in the area of the mold 52 by the plurality of back rollers 56 provided on the back surface side of the substrate 54, but it is flat. When the substrate 54 and the mold 52 are pressed with a cylindrical roller from both the front and back surfaces, the substrate 54 and the mold 52 are likely to be distorted because the roller diameter or the position of the contact point is different. There is a possibility that stripes may remain on the transfer film 53.

  A configuration is also employed in which the UV light 57 is applied to the entire surface of the substrate 54 on which the transfer film 53 is formed even for a device that needs to form a fine pattern only on a specific portion on the substrate 54. Therefore, it is difficult to form a fine pattern only in the specific part.

  Here, the irradiation of the UV light 25 in the present embodiment will be described in detail.

  Ideally, the UV light 25 is applied only to the linear portion where the pressing roll 13 presses the sheet-shaped mold 11. However, the UV light 25 has a certain width, and practically. There is a possibility that the UV light 25 is also irradiated to the front and rear of the linear portion where the sheet-shaped mold 11 is pressed.

  When the UV light 25 is irradiated in front of the pressurization portion, the UV curable resin 20 before transfer starts to be cured, so that there is a high possibility that transferability will be remarkably deteriorated.

  On the other hand, even when the UV light 25 is irradiated to the rear of the pressurizing portion, the applied pressure is no longer applied, and the sheet-shaped mold 11 moves away from the transparent substrate 12 quickly, which improves the transferability. I cannot expect much contribution.

  In the present embodiment, the UV irradiator 16 is always disposed almost immediately below the pressing roll 13 (see FIG. 2), so that the UV light 25 is surely applied to the pressing portion where the pressing roll 13 contacts the sheet-shaped mold 11. Can be irradiated.

  And the light-shielding mask 24 which prevents that the UV light 25 is irradiated to the location away from the pressurization location is installed in the UV irradiator 16, and the press roll 13 and the UV irradiator 16 are constant in the feed direction. Since it is moved, the UV light 25 is sequentially irradiated only to the pressurizing portion, and stable transfer molding can be realized.

  The sheet-shaped mold 11 may be a resin mold or a metal mold. However, the sheet-shaped mold 11 is held in a state in which a tension is applied. Therefore, in consideration of the elastic deformation and plastic deformation of the mold due to the tension, the sheet-shaped mold 11 The mold 11 is preferably a metal mold such as Ni.

  Of course, when the sheet mold 11 is a metal mold, the UV light 25 for curing the UV curable resin 20 applied on the transparent substrate 12 such as glass is not from the sheet mold 11 side but the UV light 25. It is essential to have a configuration in which light is irradiated from the back surface side of the transparent substrate 12 that can transmit light.

  Even in such a case, since the light shielding mask 24 is installed between the UV irradiator 16 and the quartz base 21 which is a transparent support base, the UV light 25 is applied only to a predetermined portion of the UV curable resin 20. In addition, patterning by the nanoimprint method is possible.

  The uncured UV curable resin 20 that is not irradiated with the UV light 25 may be removed with a predetermined cleaning liquid after mold release.

  Here, the oscillation of the UV irradiator 16 will be described.

  In recent years, a UV LED light source in which a large number of LEDs (Light Emitting Diodes) are arranged is often used as a light source of the UV irradiator 16 from the viewpoint of energy saving.

  However, since such an LED light source is used as a linear surface light source in which point light sources are superimposed, uneven luminance and uneven illuminance may occur in the width direction of the light source, that is, in this case, in the longitudinal direction of the pressure roll 13. .

  On the other hand, when such uneven brightness and uneven illuminance occur, insufficient curing and uneven curing of the UV curable resin 20 are likely to occur.

  Therefore, the UV irradiator 16 is swung in a direction perpendicular to the feeding direction of the pressing roll 13, that is, the substrate width direction of the transparent substrate 12 here, at a sufficiently high speed with respect to the feeding speed of the pressing roll 13. It is desirable to irradiate the light 25.

  When the UV irradiator 16 is swung in this way, the luminance unevenness and the illuminance unevenness in the longitudinal direction of the pressing roll 13 are almost eliminated, and transfer molding in which the UV curable resin 20 is hardly insufficiently cured and unevenly cured is realized. be able to.

  By the way, when the UV light 25 irradiated through the light shielding mask 24 is not parallel light but light having a certain spread angle, the UV light 25 that has passed through the light shielding mask 24 is transmitted between the light shielding mask 24 and the transparent substrate 12. As a result, the same phenomenon as when the patterning accuracy formed on the light-shielding mask 24 in accordance with the fine pattern 23b deteriorates results. May occur.

  Of course, if the UV light 25 is parallel light, such a phenomenon is avoided, but in order to make the light from the LED light source parallel light, it is generally necessary to install a lens on the surface of the light source. Yes, in order to make the UV light 25 almost perfect parallel light, a relatively large lens is installed, which may cause the LED mounting density to decrease or the irradiation intensity corresponding to the required exposure amount to not be obtained. It is necessary to.

  However, in a general nanoimprint material, the minimum patterning accuracy and exposure amount are almost constant and may not be so large, and the thickness of the transparent substrate 12 is usually 0.7 mm to 1.0 mm. In consideration, the UV light 25 does not need to be parallel light, and it is sufficient if the spread angle is a certain value or less.

  Therefore, it is desirable to use a light source for collimating the UV irradiator 16 so that the spread angle of the UV light 25 is 5 degrees or less.

  Then, a practically sufficient exposure amount can be obtained, and transfer patterning with high precision patterning can be realized.

  Here, the movement of the substrate discharge side holding roll 14 and the substrate insertion side holding roll 15 in the vertical direction will be described in detail with reference mainly to FIG.

  Here, FIGS. 3A to 3C are schematic sectional views (No. 1 to No. 3) of the fine pattern forming apparatus according to the first embodiment of the present invention.

  If the substrate insertion side holding roll 15 and the substrate discharge side holding roll 14 are fixed, both ends are fixed by the substrate insertion side holding roll 15 and the substrate discharge side holding roll 14 while a predetermined tension is maintained. The angle between the mold 11 and the transparent substrate 12 varies depending on the position of the pressing roll 13.

  In the present embodiment, the angle θ1 between the sheet-shaped mold 11 and the transparent substrate 12 on the substrate discharge side holding roll 14 side is also equal to the sheet-shaped mold 11 and the transparent substrate 12 on the substrate insertion side holding roll 15 side. The angle θ2 is also maintained at a predetermined size.

  This is because the holding roll control unit 18 (see FIG. 2) moves the substrate insertion side holding roll 15 and the substrate discharge side holding roll 14 in the vertical direction according to the position of the pressing roll 13.

  More specifically, it is as follows.

  FIG. 3A shows a state where the pressing roll 13 is lowered to the position of the run-up plate 22 on the substrate discharge side.

  Since the pressing roll 13 is once lowered onto the running plate 22, the UV curing to the fine pattern 23 a formed on the surface of the sheet mold 11 is performed after the variation in the pressing force due to the deformation of the pressing roll 13 is alleviated. Filling of the resin 20 is started, and the quality of the fine pattern 23b transferred and formed on the end portion of the transparent substrate 12 is remarkably improved.

  The width of the run-up plate 22 in the feeding direction of the pressing roll 13 is set so that the deformed pressing roll 13 does not come into contact with the transparent substrate 12 in the portion of the sheet-shaped mold 11 pressed by the deforming pressing roll 13. It is desirable that the width of the pressing roll 13 is wider than that in the feeding direction.

  And the clearance gap and level | step difference regarding the feed direction of the press roll 13 between the run-up board 22 and the transparent substrate 12 should be few so that the press roll 13 may be moved to the transparent substrate 12 in the state where the applied pressure is stable. Is desirable.

  Furthermore, in order to suppress wrinkles caused by fluctuations in the tension of the sheet-shaped mold 11 that occur when the pressing roll 13 presses the sheet-shaped mold 11 that is an elastic body, the holding roll control unit 18 ( 2), it is desirable to control not only the vertical position of the substrate insertion side holding roll 15 and the substrate discharge side holding roll 14 but also the tension of the sheet-shaped mold 11.

  FIG. 3B shows a state in which the pressing roll 13 is moved in the feeding direction of the pressing roll 13 while sequentially pressing and releasing the sheet-like mold 11.

  In such a state, the contact area where the sheet-shaped mold 11 comes into contact with the UV curable resin 20 is determined depending on the diameter of the pressing roll 13 and the angles θ1 and θ2.

  By keeping the shape of such a contact region constant, it becomes possible to stabilize the behavior of the UV curable resin 20 being deformed and cured.

  In the contact region, the uncured portion and the cured portion of the UV curable resin 20 are mixed, but the uncured UV curable resin 20 filled in the fine pattern 23a formed on the surface of the sheet mold 11 is slowly removed. Curing contributes to improving the transfer rate, and quickly removing the cured UV curable resin 20 contributes to stabilizing the behavior at the time of mold release.

  Therefore, it is desirable that the angle θ1 at which the sheet-shaped mold 11 comes into contact with the transparent substrate 12 is large and the angle θ2 at which the sheet-shaped mold 11 is detached from the transparent substrate 12 is small, so that, for example, θ1> θ2. Dimensional design can be considered.

  FIG. 3C shows a state in which the pressing roll 13 reaches the position of the run-up plate 22 on the substrate insertion side and starts to rise with the applied pressure released.

  When the pressing roll 13 releases the applied pressure and the sheet mold 11 is detached from the UV curable resin 20, the tension applied to the sheet mold 11 by the substrate insertion side holding roll 15 and the substrate discharge side holding roll 14 is transferred. There is a possibility that the molded UV curable resin 20 is peeled off.

  Therefore, it is desirable that the pressing roll 13 release the applied pressure in an area where there is no transfer-molded UV curable resin 20 corresponding to the position of the run-up plate 22 on the substrate insertion side, for example.

  From the above explanation, the following became clear.

  Since the substrate discharge side holding roll 14 is moved in the vertical direction in synchronization with the feeding of the pressing roll 13, the angle θ <b> 1 at which the sheet mold 11 contacts the transparent substrate 12 can be kept constant.

  For this reason, the sheet-shaped mold 11 sequentially contacts the surface of the transparent substrate 12 coated with the UV curable resin 20 while maintaining a constant angle θ1, and the fine pattern formed on the surface of the sheet-shaped mold 11 is maintained. A stable filling behavior of the UV curable resin 20 to 23a is realized.

  Therefore, large-area imprinting can be realized by high-quality transfer molding in which defects that leave minute air bubbles hardly occur even under atmospheric pressure, without performing vacuum forming that requires decompression by a chamber. .

  Since the substrate insertion side holding roll 15 is moved in the vertical direction in synchronization with the feeding of the pressing roll 13, the angle θ2 at which the sheet-shaped mold 11 is detached from the transparent substrate 12 can be kept constant.

  For this reason, the sheet-shaped mold 11 is sequentially separated from the surface of the transparent substrate 12 while maintaining a constant angle θ2, and the sheet-shaped mold 11 that causes the UV curable resin 20 to peel from the transparent substrate 12 Variations in the mold release force with the transparent substrate 12 are suppressed, and a stable mold release operation with a small desorption force is realized.

  Therefore, a large-area imprint can be realized by high-quality transfer molding in which transfer defects and peeling of the fine pattern 23b hardly occur.

(Embodiment 2)
Next, the configuration and operation of the fine pattern forming apparatus of the second embodiment will be described with reference mainly to FIG.

  FIG. 4 is a schematic perspective view of the fine pattern forming apparatus according to the second embodiment of the present invention.

  The configuration and operation of the fine pattern forming apparatus of the present embodiment are similar to the configuration and operation of the fine pattern forming apparatus of the first embodiment described above.

  However, in the present embodiment, three pressing rolls 13 are provided so as to correspond to each of the three sheet-like molds 11, and the three pressing rolls 13 are adjacent to each other. The press roll 13 is moved so that the interval between the press rolls 13 provided so as to correspond to the sheet mold 11 to be maintained is maintained at a predetermined interval or more.

  The sheet-shaped mold 11 and the pressing rolls 13 may be arranged in three or more rows in the width direction of the transparent substrate 12, and the zigzag arrangement state of the pressing rolls 13, that is, the pressing roll when the axis of the adjacent pressing rolls 13 is transferred. The state of being shifted by a predetermined interval with respect to the 13 feeding directions is maintained.

  Of course, if the arrangement of the three coating units 17 is arranged side by side in parallel and the application is performed at the same timing, the arrangement of the fine pattern regions to be finally formed is not a staggered arrangement. It can be arranged side by side.

  If the fine pattern forming method of the first embodiment described above is used, both the transferability and productivity can be achieved for the transparent substrate 12 having a large area by arranging a plurality of rows of sheet-like molds 11 and pressing rolls 13. Is possible.

  However, in the first place, as a mechanism for applying a load to the pressure roll 13 supported at both ends and rotating the pressure roll 13 freely, for example, a gate-type support having a bearing capable of withstanding a load of at least about 100 kgf is required. It is.

  Therefore, in order to arrange the plurality of rows of pressing rolls 13 in parallel, such interference between the supports must be avoided, but the distance between the supports must be increased to some extent according to the size of the supports. Therefore, it may be difficult to reduce the distance between the individual areas of the fine pattern between adjacent rows that are transferred to the transparent substrate 12.

  In the present embodiment, since the staggered arrangement state of the pressing rolls 13 is maintained, interference between the supports is alleviated.

  Therefore, sufficient space is generated at both ends of the press roll 13, so that a rigid and strong support can be installed, the deflection of the press roll 13 is greatly reduced, and stable transfer molding of a high-precision fine pattern is achieved. Can be realized.

  In addition, a plurality of fine pattern regions can be formed at a narrow pitch between adjacent columns on the transparent substrate 12, wasteful regions in the transparent substrate 12 are reduced, and productivity is improved.

  Since the contact area between the sheet-shaped mold 11 and the pressing roll 13 is shifted by a predetermined interval with respect to the feeding direction of the pressing roll 13 between adjacent rows, the contour pattern of the light shielding mask 24 (see FIG. 2) is also the pressing roll. It is desirable to be shifted by a predetermined interval with respect to the 13 feeding directions.

  Further, between adjacent rows, it is desirable that the intervals between the pressing rolls 13 in the feeding direction of the pressing rolls 13 are the same as the intervals in the feeding direction of the pressing rolls 13 in each region of the fine pattern.

(Embodiment 3)
Next, the configuration and operation of the fine pattern forming apparatus according to the third embodiment will be described with reference mainly to FIG.

  FIG. 5 is a schematic perspective view of the fine pattern forming apparatus according to the third embodiment of the present invention.

  The configuration and operation of the fine pattern forming apparatus of the present embodiment are similar to the configuration and operation of the fine pattern forming apparatus of the second embodiment described above.

  However, in the present embodiment, only one pressing roll 13 is provided.

  In order to suppress variations in the pressing force in the longitudinal direction due to the deflection caused by the lengthening of the pressing roll 13 accompanying the increase in the area of the transparent substrate 12, for example, the fine pattern formation according to the second embodiment described above is used. As in the method, it is effective to split the pressing roll 13.

  However, there is no risk that the apparatus configuration is complicated by such a division of the pressing roll 13.

  That is, as in the fine pattern forming method of the present embodiment, it is also effective to use a single pressing roll 13 without dividing the pressing roll 13.

  When such a single pressing roll 13 is used, the hardness of the surface of the pressing roll 13 decreases from the center to the end in the longitudinal direction, or the diameter of the core axis of the pressing roll 13 is A configuration that decreases in the longitudinal direction from the center to the end is desirable.

  Therefore, the configuration of the pressing roll 13 will be described with reference mainly to FIG.

  6 (a) and 6 (b) are schematic cross-sectional views (part 1 and 2) of the pressing roll 13 of the fine pattern forming apparatus according to Embodiment 3 of the present invention.

  In the configuration of FIG. 6A, the hardness of the surface of the pressing roll 13 decreases from the center to the end in the longitudinal direction.

  More specifically, it is as follows.

  That is, the pressing roll 13 in the configuration of FIG. 6A includes a core shaft 81 and an elastic body 82 that covers the core shaft 81.

  The material of the elastic body 82 is urethane rubber, and the hardness of each divided part is 80, 70 and 60 from the central part toward the end part.

  Since the load applied to the pressing roll 13 is concentrated on the end of the core shaft 81, the rubber hardness at the center is increased, and the load applied to the core shaft 81 is moved to the center.

  Thus, the load applied to the end portion can be dispersed, and the pressing force in the longitudinal direction of the pressing roll 13 can be equalized.

  In addition, it is desirable that the boundaries between the divided parts are joined so that there is no gap.

  In the configuration of FIG. 6B, the diameter of the core shaft of the pressing roll 13 decreases from the center to the end in the longitudinal direction.

  More specifically, it is as follows.

  That is, the pressing roll 13 in the configuration of FIG. 6B includes the stepped core shaft 83 and the eccentric elastic body 84 that covers the stepped core shaft 83.

  The diameter of the stepped core shaft 83 is the largest at the central portion and is smaller toward the end portion.

  Since the portion with the large diameter of the stepped core shaft 83 is difficult to bend, the load is also distributed to the central portion where the pressing force of the pressing roll is difficult to be applied.

  And in the center part, since the thickness of the eccentric elastic body 84 which covers the stepped core shaft 83 is thin, the elasticity of the eccentric elastic body 84 is not so large.

  Thus, the load applied to the end portion can be dispersed, and the pressing force in the longitudinal direction of the pressing roll 13 can be equalized.

  Note that the diameter of the stepped core shaft 83 does not have to be changed stepwise from the center to the end, and may be changed smoothly so that a tapered shape is formed.

  As is clear from the above description, by using the fine pattern forming method described in the first to third embodiments, high productivity and transfer accuracy can be realized even for the transparent substrate 12 having a large area, and high quality. An optical device can be provided at low cost.

  The fine pattern forming method and fine pattern forming apparatus in the present invention can achieve high productivity and transfer accuracy, and use a UV curable roller nanoimprint technology using a UV curable resin, This is useful for use in a fine pattern forming apparatus.

DESCRIPTION OF SYMBOLS 11 Sheet-like mold 12 Transparent substrate 13 Press roll 14 Substrate discharge side holding roll 15 Substrate insertion side holding roll 16 UV irradiator 17 Coating unit 18 Holding roll control unit 20 UV curable resin 21 Quartz base 22 Advancing plate 23a Fine pattern 23b Fine pattern 24 light shielding mask 25 UV light 51 front side roller 52 mold 53 transferred film 54 substrate 55 UV irradiator 56 back side roller 61 mold 62 substrate 63 UV curable resin 64 UV light 81 core shaft 82 elastic body 83 stepped core shaft 84 thickness elasticity body

Claims (9)

With respect to the UV curable resin placed on the surface of the transparent substrate, a sheet-like long mold for forming a fine pattern on the UV curable resin is disposed on the UV curable resin. A pressing step of pressing using a pressing roll moved in the pressing roll moving direction;
While moving a UV light source for irradiating UV light in the direction of movement of the pressing roll, the UV light is applied to the UV curable resin portion under the pressed sheet-shaped long mold portion, UV light irradiation step of irradiating from the opposite side of the surface of the transparent substrate on which the UV curable resin is placed;
A fine pattern forming method comprising: The mold holding roll is used to hold both ends of the sheet-like long mold, and the mold holding roll is moved in a direction perpendicular to the surface of the transparent substrate while moving the pressing roll in the pressing roll moving direction. Including a mold holding roll moving step
The mold holding roll is moved so that the angle between the surface of the transparent substrate and the sheet-like long mold does not fluctuate despite the pressing roll being moved, The fine pattern forming method according to claim 1.   A UV light source swinging step of swinging the UV light source in a direction parallel to the surface of the transparent substrate and perpendicular to the press roll moving direction while moving the UV light source in the pressing roll moving direction; The fine pattern forming method according to claim 1 or 2.   The fine pattern forming method according to claim 1, wherein a spread angle of the irradiated UV light is 5 degrees or less. A plurality of the sheet-like long molds are provided in a direction parallel to the surface of the transparent substrate and perpendicular to the pressing roll moving direction,
A plurality of the pressing rolls are provided so as to correspond to each of the plurality of sheet-like long molds provided,
Among the plurality of pressing rolls provided, the pressing is performed so that the interval between the pressing rolls provided so as to correspond to the adjacent sheet-shaped long molds is maintained at a predetermined interval or more. The fine pattern forming method according to claim 1, wherein the roll is moved in the pressing roll moving direction. A plurality of the sheet-like long molds are provided in a direction parallel to the surface of the transparent substrate and perpendicular to the pressing roll moving direction,
The fine pattern forming method according to claim 1, wherein only one pressing roll is provided.   The method for forming a fine pattern according to claim 6, wherein the hardness of the surface of the pressing roll decreases from the center to the end in the longitudinal direction.   The method for forming a fine pattern according to claim 6, wherein the diameter of the core shaft of the pressing roll decreases from the center to the end in the longitudinal direction. A sheet-like long mold for forming a fine pattern on the UV curable resin, which is disposed on the UV curable resin placed on the surface of the transparent substrate;
A pressing roll disposed on the sheet-like long mold and moved in a predetermined pressing roll moving direction; and
A UV light source for irradiating UV light, which is moved in the pressing roll moving direction;
With
The pressing roll presses the sheet-shaped long mold placed thereon against the UV curable resin placed on the surface of the transparent substrate while being moved in the predetermined pressing roll moving direction. ,
While the UV light source is moved in the pressing roll moving direction, the UV light is applied to the UV curable resin portion under the pressed sheet-like long mold portion, and the UV curing is performed. Irradiating from the side opposite to the surface of the transparent substrate on which the resin is placed.