JP2017077689A - Matrix, transcript and method for producing matrix - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a matrix, a transcript, and a method for producing a matrix having improved mass productivity.SOLUTION: A matrix has a cylindrical or columnar base material, and an uneven structure formed on the peripheral surface of the base material. The uneven structure has a first uneven structure formed in a first region, a second uneven structure formed in a second region, and a layered structure in which the first uneven structure and the second uneven structure are layered, the layered structure being formed in a layered region between the first region and the second region.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a master, a transcript, and a method for manufacturing the master.

  In recent years, as one of the microfabrication technologies, nanoimprint technology has been developed in which a flat or cylindrical master with a fine pattern formed on its surface is pressed against a resin sheet, etc., and the fine pattern on the master is transferred to a resin sheet, etc. Development is underway. In addition, the development of masters (also called molds) used in such nanoimprint technology is also underway.

  For example, Patent Document 1 below discloses a sleeve-shaped mold in which a fine pattern is formed on a heat-reactive resist layer by irradiating a laser beam.

  The following Patent Document 2 discloses a roll-shaped mold in which two or more pattern portions are provided along the outer periphery. Patent Document 2 discloses that an unpatterned portion is further provided between the pattern portions provided on the outer periphery of the mold.

Japanese Patent No. 4977212 JP 2013-86388 A

  Here, in the molds disclosed in Patent Documents 1 and 2, a pattern is formed by irradiating the outer peripheral surface with laser light while rotating a columnar or cylindrical base material about the axis.

  In such a columnar or cylindrical master, there has been a demand for a technique for accurately patterning a wide area of the outer peripheral surface of a base material. However, for example, when the slider for moving the laser light source in the axial direction of the substrate is lengthened, there is a problem that the accuracy of the pattern shape is lowered because the positioning accuracy of the slider is lowered. Further, when the exposure time for forming the pattern is increased, there is a problem that the accuracy of the pattern shape is lowered due to thermal expansion or the like. That is, the master disc patterned on a wide area on the outer peripheral surface has low mass productivity.

  Therefore, the present invention has been made in view of the above problems, and an object of the present invention is to provide a new and improved master disc having higher mass productivity, a transcript of the master disc, and production of the master disc. It is to provide a method.

  In order to solve the above problems, according to an aspect of the present invention, a cylindrical or columnar base material and a concavo-convex structure formed on an outer peripheral surface of the base material, the concavo-convex structure is a first The first concavo-convex structure formed in the region, the second concavo-convex structure formed in the second region, the first concavo-convex structure, and the second concavo-convex structure are overlapped to form the first region. And a superposition structure formed in a superposition region between the first region and the second region.

  The width of the overlapping region in the axial direction of the base material may be 1 μm or less.

  The first concavo-convex structure and the second concavo-convex structure may have the same pattern shape.

  Moreover, in order to solve the said subject, according to another viewpoint of this invention, the transcription | transfer material by which the inversion structure with respect to the uneven structure formed in the outer peripheral surface of the above-mentioned original disk was formed in the surface is provided. .

  Furthermore, in order to solve the above-described problem, according to another aspect of the present invention, a first concavo-convex structure is formed on the outer peripheral surface of a cylindrical or columnar substrate using a first laser beam, Forming a second concavo-convex structure using a second laser beam; and forming the second concavo-convex structure using a second laser beam at an end of a region where the first concavo-convex structure is formed. And a method of manufacturing a master, including a step of superposing and forming.

  The width in the axial direction of the base material of the region where the first concavo-convex structure and the second concavo-convex structure are superimposed is 5 of the irradiation interval of the second laser light in the axial direction of the base material. It may be less than double.

  The method may further include a step of stopping the overlapping formation of the second concavo-convex structure based on a change in reflected light from the base material.

  The overlapping formation of the second concavo-convex structure may be stopped when the reflected light of the second laser light changes over the circumference of the base material for one round or more.

  The change in the reflected light may be a change in the intensity of the reflected light.

  The distance between the irradiation position of the first laser light and the irradiation position of the second laser light may be smaller than the distance at which the second concavo-convex structure is formed in the axial direction of the base material.

  A third concavo-convex structure may be further formed on the outer peripheral surface of the substrate using a third laser beam.

  As described above, according to the present invention, a master having high mass productivity can be provided.

It is the perspective view which showed typically the original disk which concerns on one Embodiment of this invention. It is the schematic diagram which showed the exposure method of the original disk which concerns on the same embodiment. It is explanatory drawing which showed the aspect of formation of a superimposition area | region. It is the schematic diagram which showed an example of the optical system of the exposure apparatus which exposes the original disk concerning the embodiment. It is the schematic diagram which showed the other example of the optical system of the exposure apparatus which exposes the original disk based on the embodiment. It is explanatory drawing explaining the transfer apparatus which manufactures a transcription | transfer material using the original recording concerning the embodiment. 3 is an SEM image obtained by imaging an overlapping region of a transcript manufactured using the master according to Example 1. FIG.

  Exemplary embodiments of the present invention will be described below in detail with reference to the accompanying drawings. In addition, in this specification and drawing, about the component which has the substantially same function structure, duplication description is abbreviate | omitted by attaching | subjecting the same code | symbol.

<1. Composition of master>
First, with reference to FIG. 1, the structure of the master which concerns on one Embodiment of this invention is demonstrated. FIG. 1 is a perspective view schematically showing a master 1 according to this embodiment.

  As shown in FIG. 1, the master 1 according to the present embodiment includes, for example, a base material 10 having an uneven structure 11 formed on the outer peripheral surface.

  The master 1 is a master used for, for example, roll-to-roll nanoimprint. In the roll-to-roll nanoimprint, the concavo-convex structure formed on the outer peripheral surface can be transferred to the resin base material and the like by pressing the outer peripheral surface of the master 1 against the resin base material while rotating the master 1. . That is, the master 1 can efficiently produce a transfer product having a concavo-convex structure formed on the outer peripheral surface in a large area. In addition, the transcription | transfer material by which the uneven structure was transcribe | transferred by the original disk 1 can be used as optical bodies, such as an antireflection film, for example.

The base material 10 is, for example, a cylindrical or columnar member. The shape of the substrate 10 may be a hollow cylindrical shape having a cavity inside as shown in FIG. 1, or may be a solid columnar shape having no cavity inside. The material of the base material 10 is not particularly limited, and quartz glass (SiO ₂ ) such as fused silica glass and synthetic quartz glass, a metal such as stainless steel, and an outer peripheral surface of a metal such as stainless steel are covered with SiO ₂ or the like. Things can be used.

  Although the magnitude | size of the base material 10 is not specifically limited, For example, the length of an axial direction may be 100 mm or more, and an outer diameter may be 50 mm or more and 300 mm or less. Moreover, when the base material 10 is cylindrical shape, the thickness of a cylinder may be 2 mm or more and 50 mm or less.

  The concavo-convex structure 11 is a structure formed on the outer peripheral surface of the base material 10 and having arbitrary concavo-convex. The region where the concavo-convex structure 11 is formed includes a plurality of regions and overlapping regions provided between the regions. For example, as shown in FIG. 1, the region where the concavo-convex structure 11 is formed includes a first region 12, a second region 13, and an overlapping region 14 provided between the first region 12 and the second region 13. including.

  The first region 12 is a region where the first concavo-convex structure is formed, and the second region 13 is a region where the second concavo-convex structure is formed. The first uneven structure and the second uneven structure may have the same pattern shape or different pattern shapes. For example, the first concavo-convex structure and the second concavo-convex structure are concavo-convex structures (so-called moth-eye structures) in which the average period of the concavo-convex is not more than the wavelength of the visible light band (more specifically, not less than 100 nm and not more than 350 nm). There may be. Further, when the first concavo-convex structure and the second concavo-convex structure are moth-eye structures, the planar arrangement of the concave portions or the convex portions may be a tetragonal lattice, a hexagonal lattice, or a random arrangement. May be.

  The overlapping region 14 is a region where an overlapping structure in which the first uneven structure and the second uneven structure are overlapped is formed. The overlapping region 14 is provided between the first region 12 and the second region 13 along the outer periphery of the base material 10.

  The superimposed structure may be a structure in which the first concavo-convex structure and the second concavo-convex structure are overlapped in a plan view, and the first concavo-convex structure and the second concavo-convex structure are three-dimensionally arranged. An overlapping structure may be used. For example, when the first concavo-convex structure and the second concavo-convex structure are formed by photolithography, the overlapping region 14 is used to form the exposure and the second concavo-convex structure for forming the first concavo-convex structure. A multiple exposure region obtained by superimposing the above exposure may be used.

  Further, the width of the overlapping region 14 in the axial direction of the master 1 may be 1 μm or less. When the width of the overlapping region 14 is 1 μm or less, it is difficult to visually recognize the overlapping region 14, so that it is difficult to visually recognize the joint between the first region 12 and the second region 13. Therefore, when the concave / convex structure 11 is transferred to a large area using the master 1 and the transfer product is cut into single sheets, the overlapping region 14 is difficult to be visually recognized in the single sheets, so that the variation in quality among the single sheets is small. can do.

  As described above, in the master 1 according to the present embodiment, in the uneven structure 11 formed on the outer periphery of the base material 10, the first region 12 in which the first uneven structure is formed and the second uneven structure are formed. It is possible to make it difficult to visually recognize the joint between the second region 13 and the second region 13. Therefore, according to the present embodiment, since the master 1 in which the concavo-convex structure 11 is formed in a wider area can be produced, a transfer product having a larger area can be produced.

  In FIG. 1, the region where the uneven structure 11 is formed on the master 1 includes a first region 12 where the first uneven structure is formed and a second region 13 where the second uneven structure is formed. Although the example which contains is shown, this invention is not limited to the said illustration.

  For example, in the master 1, the region in which the concavo-convex structure 11 is formed includes the first region in which the first concavo-convex structure is formed, the second region in which the second concavo-convex structure is formed, and the third concavo-convex structure. The third region may be included. In such a case, an overlap region in which a structure in which the first uneven structure and the second uneven structure are overlapped is provided between the first region and the second region, and the second region and the second region are provided. Between the three regions, an overlapping region in which a structure in which the second uneven structure and the third uneven structure are overlapped is provided. That is, the region in which the concavo-convex structure 11 is formed only needs to include a plurality of regions and overlapping regions provided between the regions, and the number of the plurality of regions is not particularly limited.

<2. Master production method>
Then, with reference to FIGS. 2-5, the manufacturing method of the original recording 1 concerning this embodiment is demonstrated. FIG. 2 is a schematic view showing an exposure method of the master 1 according to this embodiment. 2A shows the state of the master 1 at the start of exposure, and FIG. 2B shows the state of the master 1 during exposure.

  As shown in FIG. 2, in the manufacturing method of the master 1 according to the present embodiment, the exposure to the base material 10 is performed by the exposure apparatus 2 including a plurality of laser heads.

  For example, the exposure apparatus 2 is based on the first laser head 23, the second laser head 24, the head stage 22 on which the first laser head 23 and the second laser head 24 are assembled, and the head stage 22. And a slider 21 that moves in the axial direction of the material 10. Needless to say, the assembly positions of the first laser head 23 and the second laser head 24 may be reversed.

  Further, the exposure to the base material 10 is performed by, for example, moving the head stage 22 along the slider 21 and applying laser light from the first laser head 23 and the second laser head 24 to the base material 10 that rotates about the axis center. This is done by irradiating. Thereby, the base material 10 is exposed in a spiral shape by the exposure apparatus 2.

  As described above, the base material 10 is a cylindrical or columnar member. Further, a resist layer (not shown) is formed on the outer peripheral surface of the base material 10 for pattern formation by exposure.

  The resist layer may be formed of either positive type or negative type resist. The resist used for the resist layer may be either an organic resist or an inorganic resist. As the organic resist, for example, a novolac resist or a chemically amplified resist can be used. Examples of the inorganic resist include tungsten, molybdenum, vanadium, tantalum, iron, nickel, copper, titanium, ruthenium, silver, zinc, aluminum, thallium, boron, germanium, niobium, silicon, uranium, tellurium, bismuth, A metal oxide containing one or more inorganic elements such as cobalt, chromium, tin, zirconium, and manganese can be used. In addition, although mentioned later in detail, it is preferable that a resist layer is formed with the resist from which characteristics, such as a reflectance, change before and behind exposure.

  When forming a resist layer with an organic resist, spin coating, slit coating, dip coating, spray coating, screen printing, or the like can be used. In addition, when a resist layer is formed using an inorganic resist, a sputtering method or the like can be used.

  The slider 21 moves the head stage 22 precisely in the axial direction of the substrate 10. Specifically, the slider 21 moves the head stage 22 assembled with the first laser head 23 and the second laser head 24 in the axial direction of the substrate 10 with high positioning accuracy by servo control. Thereby, the exposure apparatus 2 can irradiate a laser beam with high positional accuracy from one edge part of the base material 10 to the other edge part. The slider 21 may be, for example, a precision slider having positioning accuracy in nanometer units.

  The head stage 22 is a stage in which the first laser head 23 and the second laser head 24 are assembled with a predetermined distance apart in the axial direction of the substrate 10. The shape of the head stage 22 may be any shape as long as the first laser head 23 and the second laser head 24 can be assembled.

  Here, the distance between the first laser head 23 and the second laser head 24 is preferably smaller than the distance that the slider 21 can move in the axial direction of the substrate 10. In such a case, the exposure apparatus 2 moves the substrate 10 so that the first region 12 exposed by the first laser head 23 and the second region 13 exposed by the second laser head 24 overlap each other. Can be exposed.

  That is, the exposure apparatus 2 performs exposure so that an unexposed area (that is, an area where no pattern is formed) does not occur between the first area 12 and the second area 13. This is because the area where the pattern is not formed is easily visible even if the width of the base material 10 in the axial direction is small, so that the exposure apparatus 2 exposes so that the area where the pattern is not formed does not occur. This is because it is preferable. Therefore, in the master 1 according to this embodiment, the first laser is between the first region 12 exposed by the first laser head 23 and the second region 13 exposed by the second laser head 24. Overlapping regions subjected to multiple exposure are formed by each of the head 23 and the second laser head 24.

  The first laser head 23 and the second laser head 24 include a light source of laser light applied to the outer peripheral surface of the base material 10 and various optical systems that guide the laser light to the outer peripheral surface of the base material 10. Further, the first laser head 23 and the second laser head 24 are assembled to the head stage 22 at a predetermined distance in the axial direction on the substrate 10. As the laser light source included in the first laser head 23 and the second laser head 24, any laser light source that emits laser light can be used. For example, a solid laser light source or a semiconductor laser light source is used. Can be used. Further, the wavelength of the laser light emitted from the first laser head 23 and the second laser head 24 is not particularly limited, but may be, for example, a wavelength in a blue light band of 400 nm to 500 nm.

  Since the exposure apparatus 2 used for manufacturing the master 1 according to the present embodiment can simultaneously expose the substrate 10 using two laser light sources, the exposure apparatus 2 has a length twice as long as the movement amount of the slider 21. The area of the outer peripheral surface of the substrate 10 can be exposed. Therefore, the exposure apparatus 2 can expose the outer peripheral surface of the longer-axis base material 10 in a shorter time. Further, the exposure apparatus 2 can further expose the outer peripheral surface of the long-axis substrate 10 in a shorter time by further assembling a laser head (that is, the third and fourth laser heads) to the head stage 22. Is possible.

  The exposed substrate 10 is developed with an organic solvent, an alkaline solution, or the like, and the exposed pattern is formed on the resist layer, whereby the master 1 is manufactured. Further, the master 1 in which the exposed pattern is formed on the surface of the base 10 may be manufactured by further etching the base 10 using the resist layer on which the pattern is formed as a mask.

  Next, the overlapping region between the first region 12 and the second region 13 will be described with reference to FIG. FIG. 3 is an explanatory diagram showing a form of formation of the overlapping region. In FIG. 3, the X-axis direction is the circumferential direction of the substrate 10, and the Y-axis direction is the axial direction of the substrate 10.

  The overlapping region is a region that has been subjected to multiple exposure by each of the first laser head 23 and the second laser head 24. Specifically, as shown in FIG. 3, since the base material 10 is exposed in a spiral shape in the axial direction, the exposure region by the first laser head 23 and the second laser are moved along with the movement of the slider 21. The exposure area by the head 24 overlaps.

  Therefore, in the overlapping region 14, the first latent image 121 formed by the laser beam irradiation from the first laser head 23 is further applied to the second latent image by the laser beam irradiation from the second laser head 24. 131 is superimposed. Thus, after development, an area where only the first latent image 121 is formed becomes the first area 12, and an area where only the second latent image 131 is formed becomes the second area 13. In addition, a region where the first latent image 121 and the second latent image 131 are superimposed is a superimposed region 14.

  Here, the exposure apparatus 2 ends the exposure when the region where the first latent image 121 is formed is irradiated with the laser light from the second laser head 24 and the overlapping region 14 is formed. Then, the slider 21 is stopped.

  For example, the exposure apparatus 2 has the slider 21 at a position where it is assumed that the first laser head 23 is irradiated with laser light based on the assembly distance between the first laser head 23 and the second laser head 24. When it reaches, the exposure may be terminated and the slider 21 may be stopped. Specifically, when the distance in the axial direction of the base material 10 between the first laser head 23 and the second laser head 24 is 260 mm, the exposure apparatus 2 has a distance of 260 mm in the axial direction of the base material 10. When the exposure is performed for the number of minutes, the exposure may be terminated and the slider 21 may be stopped.

  However, the distance in the axial direction of the substrate 10 between the first laser head 23 and the second laser head 24 includes an error depending on the assembly accuracy of the laser heads 23 and 24. Further, due to thermal expansion of the slider 21 and the head stage 22, the distance in the axial direction of the substrate 10 between the first laser head 23 and the second laser head 24 may vary during exposure. . Therefore, when the exposure is terminated based on the movement distance of the slider 21 or the like as described above, it is difficult to reduce the width of the overlapping region 14 in the axial direction of the base material 10 so as not to be visually recognized.

  Therefore, it is preferable that the exposure apparatus 2 determines whether or not a latent image is formed at a position irradiated with laser light from the second laser head 24, and determines stop of exposure based on the determination. .

  Specifically, the exposure apparatus 2 determines whether or not a latent image is formed at a position irradiated with laser light from the second laser head 24 based on a change in reflected light from the outer peripheral surface of the substrate 10. It may be judged. For example, when a resist layer is formed with a resist whose reflectivity changes by exposure, the intensity of reflected light from the resist layer after exposure changes relative to the intensity of reflected light from the unexposed resist layer. Will do. Therefore, the exposure apparatus 2 determines whether or not a latent image is formed on the resist layer on the outer peripheral surface of the base material 10 by detecting a change in the intensity of reflected light from the outer peripheral surface of the base material 10. be able to.

  Further, the exposure apparatus 2 detects whether or not a latent image is formed on the resist layer on the outer peripheral surface of the substrate 10 by detecting the fluctuation range of the astigmatism of the reflected light, not the change in the intensity of the reflected light. May be judged. When a resist layer is formed of a resist that expands when exposed to light, the surface of the resist layer after the exposure has reduced flatness. Therefore, the exposure apparatus 2 detects a fluctuation amount of focus shift (ie, astigmatism) with the outer peripheral surface of the base material 10, thereby forming a latent image on the resist layer on the outer peripheral surface of the base material 10. It can be determined whether or not.

  The reflected light used for determining whether or not a latent image is formed may be reflected light of the laser light emitted from the second laser head 24. In order to control the focus of the laser light, separately, It may be the reflected light of the irradiating light. However, since the irradiation position of the focus control light is different from the irradiation position of the laser light emitted from the second laser head 24, the reflected light of the laser light emitted from the second laser head 24 is used to form a resist. It is preferable to determine whether or not a latent image is formed on the layer.

  For example, when a metal oxide whose reflectance is reduced by exposure is used for the resist layer, the exposure apparatus 2 uses the base material 10 based on whether or not the intensity of reflected light from the resist layer is equal to or less than a threshold value. It may be determined whether or not a latent image is formed on the resist layer on the outer peripheral surface. The threshold value can be appropriately set according to the intensity of the reflected laser beam, the type of metal oxide, and the pattern density of the latent image.

  Moreover, it is preferable that the exposure apparatus 2 stops the exposure when the change in the reflected light from the base material 10 is detected over the entire circumference of the base material 10. This is because, since the exposure apparatus 2 exposes the base material 10 in a spiral shape, even if the first latent image 121 and the second latent image 131 are overlapped in a partial region, the base material 10 This is because the first latent image 121 and the second latent image 131 are not necessarily overlapped and formed in other regions of the outer periphery (for example, the region on the opposite side of the outer periphery of the base material 10). Therefore, it is preferable that the exposure apparatus 2 stops the exposure when the reflected light changes over the circumference of the base material 10 over one round. Further, in order to avoid erroneous detection due to defects or the like existing on the outer periphery of the base material 10, it is preferable to stop the exposure when the reflected light changes over the outer periphery of the base material 10.

  The width of the overlapping region 14 in the axial direction of the substrate 10 is preferably 5 times or less of the irradiation interval of the laser light emitted from the second laser head 24 in the axial direction of the substrate 10. More preferably, it is as follows. Specifically, the exposure apparatus 2 exposes the substrate 10 in a spiral shape while taking a predetermined interval (also referred to as a track pitch) every round. At this time, the overlapping region 14 in which the second latent image 131 is superimposed on the first latent image 121 is preferably less than or equal to five rounds of exposure by the second laser head 24, and less than or equal to two rounds. More preferably. According to this, since the visibility of the overlapping region 14 can be reduced by reducing the width of the overlapping region 14 in the axial direction of the base material 10, the connection between the first region 12 and the second region 13. The eyes can be made difficult to see.

  Next, the optical system of the laser head that exposes the master 1 according to this embodiment will be described. 4 and 5 are explanatory views for explaining the optical systems of the first and second laser heads 23 and 24. FIG.

  First, an example of the optical system of the first and second laser heads 23 and 24 will be described with reference to FIG. An optical system 200 </ b> A shown in FIG. 4 is an optical system for determining the end of exposure based on the movement position of the slider 21. Further, the optical system 200 </ b> A shown in FIG. 4 is provided in each laser head 23, 24. However, when the pattern to be exposed is the same, the control mechanism 310 may be shared between the laser heads.

  As shown in FIG. 4, the optical system 200 </ b> A includes a laser light source 201, a first mirror 202, a photodiode (PhotoDiode: PD) 203, a condensing lens 204, and an electro-optic deflector (Electro Optical Deflector: EOD). 206, a collimator lens 205, a second mirror 207, a beam expander (BEX) 208, and an objective lens 209. The laser light source 201 is controlled by the control mechanism 310, and the laser light 210 oscillated from the laser light source 201 is applied to the base material 10 placed on the turntable 302 rotated by the spindle motor 301.

  The laser light source 201 is a light source that oscillates a laser beam 210 for exposing a resist layer formed on the outer peripheral surface of the substrate 10, for example, a semiconductor that emits a laser beam having a wavelength in the blue light band of 400 nm to 500 nm. It is a laser. The laser light 210 emitted from the laser light source 201 travels straight as a parallel beam and is reflected by the first mirror 202. The laser light 210 reflected by the first mirror 202 is condensed on the electro-optic deflection element 206 by the condensing lens 204 and then converted into a parallel beam again by the collimator lens 205. The collimated laser beam 210 is reflected by the second mirror 207 and guided horizontally to the beam expander 208.

  The first mirror 202 includes a polarization beam splitter, and has a function of reflecting one of the polarization components and transmitting the other of the polarization components. The polarization component transmitted through the first mirror 202 is photoelectrically converted by the photodiode 203, and the photoelectrically received light signal is input to the laser light source 201. Thereby, the laser light source 201 can modulate the laser beam 210 based on the feedback by the received light reception signal.

  The electro-optic deflection element 206 is an element that can control the irradiation position of the laser light 210 at a distance of about nanometers. The exposure apparatus 2 can finely adjust the irradiation position of the laser beam 210 applied to the substrate 10 by the electro-optic deflection element 206.

  The beam expander 208 shapes the laser beam 210 guided by the second mirror 207 into a desired beam shape, and the laser beam 210 is formed on the outer peripheral surface of the base material 10 via the objective lens 209. Irradiate.

  Here, while rotating the base material 10 by the turntable 302, the laser light 210 is moved in the axial direction of the base material 10, and the laser light 210 is intermittently applied to the resist layer, thereby exposing the resist layer. Is called. The laser beam 210 is moved by moving the slider 21 in the arrow R direction as described above.

  The exposure apparatus also includes a control mechanism 310 for making the irradiation position of the laser beam 210 into a two-dimensional pattern such as a tetragonal lattice shape or a hexagonal lattice shape. The control mechanism 310 includes a formatter 311 and a driver 312 and controls the irradiation of the laser light 210. The driver 312 controls the output of the laser light source 201 based on the control signal generated by the formatter. The driver 312 synchronizes the control signal from the formatter 311 and the servo signal of the spindle motor 301 for each track so that the two-dimensional pattern is synchronized for each track. Thereby, irradiation of the laser beam 210 to the resist layer of the substrate 10 is controlled.

  The exposure apparatus including the laser head including the optical system shown in FIG. 4 outputs the laser light 210 from the laser light source 201 by the driver 312 when the movement position of the slider 21 reaches the area exposed by the other laser head. Stop. As a result, the exposure apparatus can manufacture the master 1 including the overlapping region 14 in which the first latent image 121 and the second latent image 131 are superimposed.

  Next, another example of the optical system of the first and second laser heads 23 and 24 will be described with reference to FIG. An optical system 200 </ b> B illustrated in FIG. 5 is an optical system for determining the end of exposure based on a change in reflected light from the outer peripheral surface of the substrate 10. Further, the optical system 200B shown in FIG. 5 is provided in each of the laser heads 23 and 24. However, when the pattern to be exposed is the same, the control mechanism 310 may be shared between the laser heads.

  As shown in FIG. 5, the optical system 200B includes a laser light source 201, a first mirror 202, a photodiode 203, a condensing lens 204, an electro-optic deflection element 206, a collimator lens 205, a control mechanism 310, and the like. , Second mirror 207, beam expander (BEX) 208, objective lens 209, polarization conversion element 222, polarization beam splitter (PBS) 221, and photodiode (Photodiode: PD). 223. The laser light source 201 is controlled by the control mechanism 310, and the laser light 210 oscillated from the laser light source 201 is applied to the base material 10 placed on the turntable 302 rotated by the spindle motor 301.

  Here, the laser light source 201, the first mirror 202, the photodiode 203, the condenser lens 204, the electro-optic deflection element 206, the collimator lens 205, the second mirror 207, the control mechanism 310, the spindle motor 301, and the turntable 302 are described. 4 is substantially the same as the configuration described in FIG.

  The polarization conversion element 222 is composed of a quarter wavelength plate that rotates the phase of polarized light by 90 °, and is combined with the polarization beam splitter 221 to guide only the reflected light from the substrate 10 to the photodiode 223. Specifically, the laser light 210 reflected from the base material 10 has a phase difference of 180 ° by passing through the polarization conversion element 222 twice with respect to the laser light 210 irradiated on the base material 10. Become. By using the phase difference, the polarization beam splitter 221 can transmit the laser light 210 irradiated to the base material 10 and guide the laser light 210 reflected from the base material 10 to the photodiode 223.

  The laser beam 210 reflected from the substrate 10 is photoelectrically converted by the photodiode 223, and the received light signal subjected to the photoelectric conversion is input to the driver 312. The driver 312 detects the intensity of the received light signal that has been subjected to photoelectric conversion, and stops the output of the laser light 210 from the laser light source 201 when the intensity of the received light signal has changed over the circumference of the substrate 10 or more. As a result, the exposure apparatus can manufacture the master 1 including the overlapping region 14 in which the first latent image 121 and the second latent image 131 are superimposed.

  The substrate 10 having a resist layer formed on the outer peripheral surface is exposed by a laser head including the optical system described in FIGS. 4 and 5, and the exposed substrate 10 is developed, so that the exposed pattern becomes a resist. The master 1 formed in the layer can be manufactured. Further, the master 1 in which the exposed pattern is formed on the surface of the base 10 may be manufactured by further etching the base 10 using the resist layer on which the pattern is formed as a mask.

<3. Example of use of master disc>
Next, a usage example of the master 1 described above will be described with reference to FIG. The master 1 according to the present embodiment is a master used for, for example, a roll-to-roll nanoimprint. The master 1 according to the present embodiment can continuously produce a transfer product in which the concavo-convex structure 11 formed on the outer peripheral surface of the master 1 is transferred by using a transfer device with reference to FIG. FIG. 6 is an explanatory view for explaining a transfer apparatus for producing a transfer product using the master 1 according to the present embodiment.

  As shown in FIG. 6, the transfer device includes a master 1, a base material supply roll 51, a take-up roll 52, guide rolls 53 and 54, a nip roll 55, a peeling roll 56, a coating apparatus 57, and a light source. 58.

  The base material supply roll 51 is a roll in which a sheet-shaped sheet base material 61 is wound in a roll shape, and the take-up roll 52 winds up the sheet base material 61 on which the resin layer to which the concavo-convex structure 11 is transferred is laminated. It is a roll. The guide rolls 53 and 54 are rolls that convey the sheet base sheet 61 in the form of a sheet. The nip roll 55 is a roll that presses the sheet base 61 on which the resin layer is laminated against the master 1, and the peeling roll 56 is a sheet base 61 on which the resin layer is laminated after the concavo-convex structure 11 is transferred to the resin layer. Is a roll that peels from the master 1.

  The coating device 57 includes coating means such as a coater, and applies the photocurable resin composition to the sheet base 61 to form a resin layer. The coating device 57 may be, for example, a gravure coater, a wire bar coater, or a die coater. The light source 58 is a light source that emits light having a wavelength capable of curing the photocurable resin composition, and may be, for example, an ultraviolet lamp.

  In addition, a photocurable resin composition is resin hardened | cured when the light of a predetermined wavelength is irradiated. Specifically, the photocurable resin composition may be an ultraviolet curable resin such as an acrylic resin acrylate or an epoxy acrylate. Moreover, the photocurable resin composition may contain an initiator, a filler, a functional additive, a solvent, an inorganic material, a pigment, an antistatic agent, a sensitizing dye, or the like, if necessary.

  In the transfer device, first, the sheet base material 61 is continuously fed from the base material supply roll 51 through the guide roll 53. The photocurable resin composition is applied to the sent sheet base 61 by the coating device 57, and the resin layer is laminated on the sheet base 61. In addition, the sheet base material 61 on which the resin layer is laminated is pressed against the master 1 by the nip roll 55. Thereby, the concavo-convex structure 11 formed on the outer peripheral surface of the master 1 is transferred to the resin layer. The resin layer to which the concavo-convex structure 11 is transferred is cured by irradiation with light from the light source 58. Subsequently, the sheet base material 61 on which the cured resin layer is laminated is peeled from the master 1 by the peeling roll 56, sent to the winding roll 52 through the guide roll 54, and wound.

  According to such a transfer apparatus, it is possible to continuously manufacture a transfer product on which the concavo-convex structure 11 formed on the outer peripheral surface of the master 1 according to this embodiment is transferred.

  Hereinafter, the master according to the present embodiment will be described more specifically with reference to examples and comparative examples. In addition, the Example shown below is one example of conditions for showing the feasibility and effects of the master according to the present embodiment and the master manufacturing method, and the master and the master manufacturing method according to the present invention are as follows. However, the present invention is not limited to these examples.

Example 1
A resist layer made of a metal oxide was formed to a thickness of 60 nm on the outer peripheral surface of a cylindrical quartz glass substrate having a thickness of 4.5 mm, a diameter of 150 mm, and an axial length of 550 mm by sputtering.

  Subsequently, thermal lithography was performed using an exposure apparatus provided with a slider in which two laser heads were assembled with a distance of 250 mm in the axial direction of the substrate to form a latent image on the resist layer. As a laser light source, a blue semiconductor laser emitting laser light having a wavelength of 405 nm was used. The laser heads were subjected to autofocus control by the astigmatism method using separate laser beams.

  As a pattern shape to be exposed, a hexagonal lattice arrangement in which dots are arranged in a staggered pattern was used. The pitch in the circumferential direction of the substrate of the dots was 230 nm, and the pitch in the axial direction of the substrate was 160 nm. When the substrate was rotated at 900 rpm and the slide assembled with the laser light source was scanned at 2.4 μm / second in the axial direction of the substrate for 36 hours, exposure was performed over an area of about 500 mm in the axial direction of the substrate. Could be done.

  Furthermore, the exposed substrate was developed using a 2.38 mass% aqueous solution of TMAH (tetramethylammonium hydroxide), and the exposed portion of the resist layer was dissolved to form an exposure pattern on the outer peripheral surface. A master was produced.

  Note that the exposure was automatically stopped by detecting that the intensity of the reflected light of the laser beam to be exposed was equal to or less than the threshold value. Specifically, the output of the laser beam was stopped when the intensity of the reflected light was equal to or less than the threshold value over the outer circumference of the substrate. Since the intensity of the reflected light from the unexposed portion of the resist layer is 340 mV and the intensity of the reflected light from the exposed portion is 270 mV, the threshold value was set to 300 mV.

(Example 2)
An exposure apparatus provided with a slider in which a cylindrical quartz glass substrate having a thickness of 4.5 mm, a diameter of 150 mm, and an axial length of 800 mm is used, and three laser heads are assembled 250 mm apart in the axial direction of the substrate. A master was manufactured in the same manner as in Example 1 except that thermal lithography was performed. In Example 2, the exposure could be performed over an area of about 750 mm in the axial direction of the substrate in 36 hours.

(Example 3)
A master was manufactured in the same manner as in Example 1 except that the exposure was automatically stopped by detecting that the position coordinates of the slider with the laser head assembled reached 250 mm. In Example 2, the exposure could be performed over an area of about 500 mm in the axial direction of the substrate in 36 hours.

(Comparative Example 1)
A master was manufactured in the same manner as in Example 1 except that thermal lithography was performed using an exposure apparatus having a slider with one laser head assembled. In Comparative Example 1, the exposure could be performed over an area of about 250 mm in the axial direction of the substrate in 36 hours.

(Evaluation of the master)
In the masters produced in Examples 1 to 3 and Comparative Example 1, the concavo-convex structure on the outer peripheral surface of the master was transferred to a transferred material, and the axial width of the base material in the overlapping region was measured with an optical microscope. Furthermore, the visibility of the overlapping region was evaluated visually. The results are shown in Table 1. Note that “−” represents a case where there is no overlapping region and a case where the evaluation cannot be performed. “A” represents that the overlapping area was not visually recognized, and “B” represents that the overlapping area was visually recognized.

  As shown in Table 1, it can be seen that Examples 1 to 3 can form a pattern in a wider area in the same exposure time as in Comparative Example 1. Moreover, even when an overlapping area exists, it turns out that Example 1 and 2 can make the width | variety of an overlapping area small compared with Example 3, and is not visually recognized visually.

  In addition, an overlapping area of a transcript produced using the master according to Example 1 was observed with a scanning electron microscope (SEM), and was captured at a magnification of 30,000 or 60,000. Is shown in FIG. 7A is an SEM image obtained by imaging the overlapping area of the transcript at an enlargement magnification of 30,000 times, and FIG. 7B is an image of the overlapping area of the transcript at an enlargement magnification of 60,000 times. This is a SEM image. Moreover, the vertical direction when facing the image of FIG. 7 is the axial direction of the base material, and the horizontal direction is the circumferential direction of the base material.

  Referring to FIG. 7A, although there is an overlapping area in the center of the image, the first area and the second area that exist above and below the image across the overlapping area are almost indistinguishable. You can see that Also, referring to FIG. 7B, it can be seen that the width of the overlapping region where the pattern is larger than that of the first region and the second region is approximately 300 nm because of the multiple exposure. That is, it can be seen that the overlapping area of the master disk according to Example 1 has a width in the axial direction of the base material of 1 μm or less and twice or less of an exposure pitch in the axial direction of the base material.

  As described above, according to an embodiment of the present invention, it is possible to provide a master disk in which a concavo-convex structure is formed in a wider area and an overlapping area that is a joint between patterns of the concavo-convex structure is difficult to visually recognize. . Therefore, according to one embodiment of the present invention, it is possible to provide a master having higher mass productivity and a method for manufacturing the master. In addition, it is possible to improve the mass productivity of the transcript of the master according to this embodiment.

  The preferred embodiments of the present invention have been described in detail above with reference to the accompanying drawings, but the present invention is not limited to such examples. It is obvious that a person having ordinary knowledge in the technical field to which the present invention pertains can come up with various changes or modifications within the scope of the technical idea described in the claims. Of course, it is understood that these also belong to the technical scope of the present invention.

Master 1
Base material 10
Uneven structure 11
First region 12
Second region 13
Overlapping area 14
Exposure device 2
Slider 21
Headstage 22
First laser head 23
Second laser head 24

Claims (11)

A cylindrical or columnar substrate;
The concavo-convex structure formed on the outer peripheral surface of the substrate;
With
The uneven structure is
A first concavo-convex structure formed in the first region;
A second concavo-convex structure formed in the second region;
An overlapping structure formed in an overlapping region between the first region and the second region by overlapping the first uneven structure and the second uneven structure;
Including the master.   The master according to claim 1, wherein a width of the overlapping region in the axial direction of the base material is 1 μm or less.   The master according to claim 1, wherein the first concavo-convex structure and the second concavo-convex structure have the same pattern shape.   A transfer product, wherein a reverse structure with respect to the concavo-convex structure formed on the outer peripheral surface of the master according to any one of claims 1 to 3 is formed on the surface. Forming a first concavo-convex structure on the outer peripheral surface of a cylindrical or columnar substrate using a first laser beam, and forming a second concavo-convex structure using a second laser beam;
A step of superimposing the second concavo-convex structure on the end portion of the region where the first concavo-convex structure is formed using a second laser beam;
A method for manufacturing a master, including   The width in the axial direction of the base material of the region where the first concavo-convex structure and the second concavo-convex structure are superimposed is 5 of the irradiation interval of the second laser light in the axial direction of the base material. The method for producing a master according to claim 5, wherein the master disk is twice or less.   The master disc manufacturing method according to claim 5, further comprising a step of stopping the formation of the second concavo-convex structure based on a change in reflected light from the base material.   The master disk manufacturing method according to claim 7, wherein the formation of the second concavo-convex structure is stopped when the reflected light of the second laser light changes over the circumference of the base material for one round or more.   The method for manufacturing a master according to claim 7 or 8, wherein the change in the reflected light is a change in the intensity of the reflected light.   The distance between the irradiation position of the first laser light and the irradiation position of the second laser light is smaller than the distance at which the second concavo-convex structure is formed in the axial direction of the base material. The manufacturing method of the original disk as described in any one of -9. The method for manufacturing a master according to any one of claims 5 to 10, wherein a third concavo-convex structure is further formed on the outer peripheral surface of the base material using a third laser beam.