Method for forming large-area pattern using nanoimprint

Abstract

The present invention relates to a method for forming a large-area nanopattern having a continuous shape by using a first mold including a first pattern and a first light-shielding target region, and a second mold including a second pattern and a second light-shielding target region. The first pattern and the second pattern may be imprinted by sequentially irradiating ultraviolet rays by aligning the first mold and the second mold, after applying a resin on a substrate composed of a first zone and a second zone connected to each other. Here, the light-shielding target region of each mold may partially shield different zones adjacent to each other, thereby preventing non-uniform curing at an adjacent boundary.

Description

Method for forming large-area patterns using nanoimprint

[0001] The present invention relates to a method for forming a large-area pattern using a nanoimprint, and more specifically, to a method for forming a pattern continuously without seam lines when forming a pattern larger than a conventional nanomold.

[0002] Nanoimprint lithography (NIL) is a technology that transfers nano or micro-level patterns onto a substrate like a stamp using fine precision molds, and it is attracting attention as a next-generation patterning technology capable of replacing conventional photolithography or electron beam lithography.

[0003] The nanoimprint process does not require complex exposure optical systems and offers the advantages of a simple process configuration and low processing costs. Due to these characteristics, it is a technology capable of forming nano-patterned structures of various sizes and functionalities at a low cost, and is being actively researched in fields such as displays, optical devices, semiconductors, and biochips.

[0004] Nanoimprint lithography is a method of forming a pattern of a desired shape on a substrate by applying a curable resin that reacts to ultraviolet (UV) light or heat onto a substrate, pressing a mold with a predetermined pattern onto the substrate to deform and cure the resin, and then removing the mold.

[0005] In this case, the mold has a shape opposite to the pattern to be formed, and since high resolution is possible, it is possible to secure superior resolution compared to conventional photolithography methods that are limited to long-wavelength light sources.

[0006] In particular, for optical devices such as waveguide-based displays or HUDs (Head-Up Displays), it is necessary to control the incidence, diffusion, and emission of light by forming nano-patterns inside the waveguide, and nanoimprint technology is being applied to form these nano-structures.

[0007] For example, when different shaped patterns need to be formed in multiple regions performing different optical functions, such as in-couplers, expanders, and out-couplers, a mold structure suitable for each must be used.

[0008] However, conventional nanoimprint lithography technology faces technical difficulties in precisely and simultaneously realizing nanopatterns of different shapes within a master mold. Since the processes for realizing each pattern differ in application conditions and resolution characteristics, it is difficult to realize them in combination on a single master.

[0009] Furthermore, manufacturing large-area displays requires implementing uniform nano-patterns on substrates of several hundred millimeters or more; however, conventional master molds could not cover the entire area in a single process due to size limitations.

[0010] To solve this, a method of connecting multiple masters in parallel or transferring them sequentially has been proposed, but this process results in optical non-uniformity due to alignment errors and shim lines, which causes device performance degradation or defects after pattern transfer.

[0011] In particular, light leakage, reflection loss, and phase distortion in the seam line area act as problems and can degrade the quality of high-resolution displays.

[0012] As such, there is an increasing need for new imprint-based manufacturing technologies that can integrate nano-patterns with different functions onto a single master or precisely join multiple identical patterns to form large-area structures while suppressing defects such as seam lines.

[0013] The present invention aims to provide a method for forming a continuous large-area nano pattern without seam lines by precisely joining multiple patterns through a nanoimprint process.

[0014] In addition, the present invention aims to provide a process that enables the realization of a large-area pattern by easily aligning and combining a plurality of soft molds.

[0015] The problems to be solved by the present invention are not limited to the technical problems mentioned above, and other technical problems not mentioned will be clearly understood by those skilled in the art to which the present invention belongs from the description below.

[0016] A continuous large-area nano pattern can be formed by using a first mold including a first pattern and a first light-blocking target area and a second mold including a second pattern and a second light-blocking target area, applying resin onto a substrate composed of adjacent first and second zones, aligning the first mold and then irradiating with ultraviolet light to imprint the first pattern, and aligning the second mold and then irradiating with ultraviolet light to imprint the second pattern.

[0017] A masking layer can be applied to the first light-blocking target area and the second light-blocking target area.

[0018] The area where the first pattern is formed and the first light-blocking target area, and the area where the second pattern is formed and the second light-blocking target area can be formed consecutively.

[0019] By recognizing the alignment marker formed on the second mold as an alignment device, the second mold can be aligned so that the first pattern and the second pattern are continuous.

[0020] The first mold may include a first transmission area that extends from the first light-blocking target area, corresponds to the first zone when aligned, and is masked so that some ultraviolet light is transmitted.

[0021] A masking layer may be applied to the upper surface of the second zone before applying the resin.

[0022] The above masking layer can be removed together with the cured resin.

[0023] A masking layer can be applied to the lower surface of the above description.

[0024] When applying resin to the substrate, it may be applied excluding the first offset zone adjacent to the second zone and the second offset zone adjacent to the first zone.

[0025] A substrate comprising adjacent first and second zones, a first mold including a first pattern arranged to correspond to the first zone and a first light-blocking target area extended toward the second zone, and a second mold including a second pattern arranged to correspond to the second zone and a second light-blocking target area extended toward the first zone, can be configured so that when irradiated with ultraviolet rays, the first pattern and the second pattern are imprinted in a continuous shape.

[0026] According to one embodiment of the present invention, a continuous large-area nano pattern without seam lines can be formed by precisely aligning and transferring a plurality of soft molds.

[0027] In addition, high-quality optical components can be realized by controlling transfer conditions to prevent optical non-uniformity from occurring in the boundary regions between each mold.

[0028] In addition, by simplifying the alignment structure and process steps, the large-area nano-pattern formation process can be performed efficiently.

[0029] Further scopes of the applicability of the present invention will become apparent from the following detailed description. However, since various changes and modifications within the spirit and scope of the present invention are clearly understood by those skilled in the art, specific embodiments, such as the detailed description and preferred embodiments of the present invention, should be understood as being given merely as examples.

[0030] FIG. 1 is a schematic representation of a large-area nano pattern according to one embodiment of the present invention.

[0031] FIG. 2 is a schematic diagram of a mold according to one embodiment of the present invention.

[0032] FIG. 3 schematically illustrates a method for forming a large-area pattern using a nanoimprint according to one embodiment of the present invention.

[0033] FIG. 4 is a flowchart of a method for forming a large-area pattern using a nanoimprint according to one embodiment of the present invention.

[0034] FIG. 5 is a drawing for explaining a transmission area according to an embodiment of the present invention.

[0035] FIG. 6 illustrates an example of a transmission area according to one embodiment of the present invention.

[0036] FIG. 7 schematically illustrates a method for forming a large-area pattern using a nanoimprint according to one embodiment of the present invention.

[0037] FIG. 8 schematically illustrates a method for forming a large-area pattern using a nanoimprint according to another embodiment of the present invention.

[0038] FIG. 9 schematically illustrates a method for forming a large-area pattern using a nanoimprint according to another embodiment of the present invention.

[0039] Hereinafter, embodiments disclosed in this specification will be described in detail with reference to the attached drawings. Identical or similar components regardless of drawing symbols are given the same reference number, and redundant descriptions thereof will be omitted.

[0040] The suffixes "module" and "part" for components used in the following description are assigned or used interchangeably solely for the sake of ease of drafting the specification, and do not inherently possess distinct meanings or roles. Furthermore, in describing the embodiments disclosed in this specification, detailed descriptions of related prior art are omitted if it is determined that such detailed descriptions could obscure the essence of the embodiments disclosed in this specification.

[0041] In addition, the attached drawings are intended only to facilitate understanding of the embodiments disclosed in this specification, and the technical concept disclosed in this specification is not limited by the attached drawings; it should be understood that all modifications, equivalents, and substitutions included within the concept and technical scope of the present invention are included.

[0042] Terms including ordinal numbers, such as first, second, etc., may be used to describe various components, but said components are not limited by said terms. These terms are used solely for the purpose of distinguishing one component from another.

[0043] When it is stated that one component is "connected" or "connected" to another component, it should be understood that while it may be directly connected or connected to that other component, there may also be other components in between. On the other hand, when it is stated that one component is "directly connected" or "directly connected" to another component, it should be understood that there are no other components in between.

[0044] A singular expression includes a plural expression unless the context clearly indicates otherwise.

[0045] In this application, terms such as “comprising” or “having” are intended to specify the existence of the features, numbers, steps, actions, components, parts, or combinations thereof described in the specification, and should be understood as not precluding the existence or addition of one or more other features, numbers, steps, actions, components, parts, or combinations thereof.

[0046] FIG. 1 is a schematic representation of a large-area nano pattern according to one embodiment of the present invention.

[0047] As mentioned above, in order to manufacture large-area displays, a uniform nano pattern over a wider area is sometimes required. However, since the silicon wafers currently in general use are limited to a size of 12 inches, it is impossible to implement a large-area nano pattern exceeding 12 inches on a single wafer, and a method of implementing the pattern over multiple areas or substrates and then precisely joining them together is required.

[0048] Referring to FIG. 1, on the substrate (100), a first pattern (10) and a second pattern (20) are formed in a continuous manner in contact with each other, and through them, a single large-area nano pattern is realized overall.

[0049] The first pattern (10) and the second pattern (20) are each formed from independent molds, and the two patterns can be connected at the boundary without seams or steps. Generally, when a large-area pattern is realized by joining multiple patterns, seam lines may be formed at the connection points, which may cause optical non-uniformity or physical defects; however, this embodiment is designed to minimize such problems. This will be explained in detail in the following drawings.

[0050] These large-area nano-patterns are not necessarily limited to cases where different types of patterns are connected, but can also be applied when expanding the same pattern to realize a single wide pattern.

[0051] Meanwhile, the large-area nano pattern illustrated in FIG. 1 can be implemented on various types of substrates (100). For example, the final master mold can be formed on a glass substrate, or it can be implemented by first forming a first pattern (10) and a second pattern (20) on a soft mold and then transferring them to a glass substrate (100). The selection of the substrate (100) and the transfer method can be selected according to the ease of the manufacturing process and the physical property requirements of the final product.

[0052] FIG. 2 is a schematic diagram of a mold according to an embodiment of the present invention. FIG. 2 schematically illustrates the configuration of a first soft mold (310) and a second soft mold (320) according to an embodiment of the present invention.

[0053] The first pattern (10) is replicated from the first master mold (210) and formed in the first soft mold (310), and the second pattern (20) is replicated from the second master mold (220) and formed in the second soft mold (320).

[0054] In FIG. 2, based on the positions of the first pattern (10) and the second pattern (20) formed in the first soft mold (310) and the second soft mold (320), a virtual area where the respective first master mold (210) and second master mold (220) originally replicated these patterns existed is shown by dotted lines, etc.

[0055] To explain in more detail with reference to FIG. 4, the master mold is generally manufactured on a substrate such as a silicon wafer (S4100), and the soft mold is formed by transferring from the master mold using a transparent film material substrate (S4200).

[0056] This transfer process can be performed using a curing resin or by a nanoimprint lithography process. Through this process, the pattern formed on each master mold can be replicated to each soft mold.

[0057] Referring again to FIG. 2, the replicated first pattern (10) is formed in a region of the first soft mold (310), and the edge thereof can be defined as the first side (11). Likewise, the second pattern (20) is formed at a corresponding position of the second soft mold (320), and the edge thereof can be defined as the second side (21).

[0058] The first side (11) and the second side (21) are arranged to come into contact with each other when the mold is aligned on the substrate, thereby enabling the realization of a continuous, large-area nano pattern without steps. In other words, the outer regions of the first side (11) and the second side (21) must be restricted from transfer.

[0059] Accordingly, a first light-blocking target area (311) is set in the first soft mold (310), and a masking layer (311), which is a light-blocking layer for blocking the transmission of ultraviolet rays, can be applied to the area (S4300).

[0060] The light-blocking layer, i.e., the masking layer (311), may be composed of a metal film, an opaque resin, or other material having a UV-blocking function, and may be configured to prevent unnecessary exposure of ultraviolet rays before imprinting of the second soft mold (320).

[0061] Similarly, the second soft mold (320) has a light-blocking layer (321) formed therein corresponding to the second light-blocking target area, so that ultraviolet rays can be blocked so as not to affect the cured state of the first pattern (10).

[0062] The light-shielding target area of ​​the present invention refers to an area that must be shielded or has the potential to be shielded while ultraviolet rays are irradiated, and it does not necessarily have to be an area that is actually shielded by applying a masking layer.

[0063] That is, it can be interpreted as a candidate area where a masking layer can be applied, or a managed area set considering the need for light shielding. Such a light-shielding target area is not limited to soft molds and can be set in various parts that may be located in the UV irradiation path during the nanoimprint lithography process.

[0064] Meanwhile, as reference points for alignment, an alignment marker (312) may be formed on the first soft mold (310) and an alignment marker (322) may be formed on the second soft mold (320). Each alignment marker (312, 322) is placed on the outer edge of the mold or at a predetermined location and is implemented as a structure that is optically recognizable by the mold alignment device.

[0065] These alignment markers can be utilized as reference points to adjust the position and rotation angle of the molds, and can play a role in helping two molds be closely aligned at the nanometer level. In this process, the alignment markers can contribute to correcting relative positional errors between the molds or improving the alignment accuracy of continuous pattern formation.

[0066] In this way, the first soft mold (310) and the second soft mold (320) according to one embodiment of the present invention each have a pattern replicated from an independent master mold and are configured to include a light-blocking layer (311, 321) and an alignment marker (312, 322), thereby enabling the simultaneous formation of a continuous nano pattern and prevention of interference between molds.

[0067]

[0068] Hereinafter, a method for forming a large-area pattern using a nanoimprint according to an embodiment of the present invention will be described with reference to FIGS. 3 and 4. FIG. 3 is a schematic representation of a method for forming a large-area pattern using a nanoimprint according to an embodiment of the present invention. FIG. 4 is a flowchart of a method for forming a large-area pattern using a nanoimprint according to an embodiment of the present invention.

[0069] First, referring to FIG. 4, a plurality of master molds including a first master mold (210) and a second master mold (210) are fabricated using a silicon substrate, etc. (S4100). At this time, the formation of the nano pattern can be performed by patterning a photosensitive film on a silicon substrate using, for example, electron beam lithography (e-beam lithography), photolithography, or a focused ion beam (FIB), and then forming a nano structure through an etching process.

[0070] A desired nano pattern is formed on each master mold, and alignment markers (312, 322) may be formed together on the edges of the master mold so that multiple patterns are formed in succession in a subsequent process (see FIG. 2).

[0071] Subsequently, a soft mold is transferred using the produced master mold (S4200). The soft mold may be, for example, a transparent polymer film material, and is produced in such a way that the pattern on the master mold is replicated onto the soft mold. It is preferable that the soft mold be formed from a material that allows ultraviolet light to pass through.

[0072] Master molds are manufactured using expensive processes and have a tendency to be easily damaged, so they lack durability for repeated use. In addition, most master molds do not transmit ultraviolet light, making them unsuitable for imprint processes that require UV curing. Accordingly, by replicating the pattern of the master mold onto a soft mold composed of a transparent polymer film or the like that has excellent UV transmittance, it is possible to use it repeatedly and adhere it to curved surfaces, and it is easy to separately form alignment markers (312, 322) or light-blocking structures.

[0073] Next, a masking layer is applied to the light-blocking target area located at the edge of each soft mold (S4300). This masking layer is composed of a metallic material or other opaque material capable of blocking ultraviolet rays, and is intended to prevent overlapping exposure or uneven photocuring from occurring at the boundary between molds when transferring to the final master (see FIG. 2).

[0074] Hereinafter, the formation method will be explained with reference to FIG. 3. FIG. 3 is a schematic diagram for convenience of explanation and is a schematic representation of the side view, where the arrow indicates ultraviolet light.

[0075] First, a master mold including a first master mold and a second master mold is fabricated using a silicon substrate (S4100). At this time, a desired nano pattern is formed on each master mold, and alignment markers may be formed together on the edges of the master molds so that multiple patterns can be formed continuously in a subsequent process.

[0076] The formation of a nano pattern can be performed by patterning a photosensitive film on a silicon substrate using, for example, electron beam lithography (e-beam lithography), photolithography, or a focused ion beam (FIB), and then forming a nano structure through an etching process.

[0077] Subsequently, a soft mold is transferred using the manufactured master mold (S4200). Master molds are produced using expensive processes and are prone to damage, so they lack durability for repeated processes when used directly. Additionally, most master molds do not transmit ultraviolet light, making them unsuitable for imprint processes that require UV curing. Accordingly, by replicating the pattern of the master mold onto a soft mold composed of a transparent polymer film or the like that has excellent UV transmittance, it is possible to use it repeatedly and adhere it to curved surfaces, and there is an advantage in that it is easy to separately form alignment markers or light-blocking structures.

[0078] Next, a masking layer is applied to the light-blocking target area located at the edge of each soft mold (S4300). This masking layer is made of a metallic material or other opaque material capable of blocking ultraviolet rays, and is intended to prevent overlapping exposure or uneven light curing from occurring at the boundary between molds when transferring to the final master.

[0079] Referring to S3001 in FIG. 3, a UV-curable resin is applied to a substrate on which a large-area nano pattern is to be formed (S4400). The resin can be applied uniformly, for example, by spin coating or an inkjet method.

[0080] At this time, the material may be divided into a first zone (110) and a second zone (120). This division is established according to the area where the pattern formed in each soft mold is transferred, and can be described as a conceptual division to ensure clarity in the pattern alignment and UV irradiation process.

[0081] Referring to S3002 in FIG. 3, a first soft mold (310) can be aligned on the applied resin (S4500). At this time, the first soft mold (310) can be aligned such that the first pattern (10) faces the first zone (110) and the first light-blocking target area (311) is located in the second zone (120). Additionally, an alignment marker (312) formed on the first soft mold (310) can be recognized by an alignment device, thereby allowing the position and angle of the first soft mold (310) to be adjusted.

[0082] After aligning the first soft mold to the correct position using an alignment marker, the first pattern is transferred to the resin by irradiating with ultraviolet (UV) light (S4600). When irradiating with UV light, the UV light does not reach the area to be shielded by the masking layer, so that the area is not cured.

[0083] Next, after removing the first soft mold (310), uncured resin may remain in the light-blocking target area (311) located in the second zone (120) where ultraviolet light does not reach. Accordingly, the subsequent process can be prepared by wiping away or cleaning to remove the remaining resin (S3003). At this time, resin cured by ultraviolet irradiation exists in the first zone (110), and the first pattern (10) is transferred onto this cured resin.

[0084] Referring to S3003 and S3004 in FIG. 3, after removing the first soft mold, the uncured resin remaining in the light-shielding target area that has not yet been cured can be removed, and a new resin can be reapplied. This process is a pretreatment process to prevent interference between patterns or non-uniformity when residual resin remains in an area where no pattern is formed.

[0085] At this time, resin may also be applied to the first zone (110). This is because if the resin is applied selectively only to the second zone (120), an additional process requiring precise pattern boundary control may be required, and by applying the resin to the entire area, the process can be simplified.

[0086] Referring to S3005 of FIG. 3, the second soft mold (320) can be aligned (S4700). At this time, the second soft mold (320) can be aligned such that the second pattern (20) faces the second zone (120) and the second light-blocking target area (321) is located in the first zone (110).

[0087] In addition, by utilizing alignment markers (322), the two patterns can be aligned to the correct position and aligned according to the same criteria as the first soft mold (310), so that the two patterns can be implemented in a continuous form.

[0088] Once alignment is complete, ultraviolet light is irradiated so that the second pattern (20) formed in the second soft mold (320) can be transferred to the second zone (120) (S4800). At this time, since the second light-blocking target area (321) is located in the first zone (110), ultraviolet light does not reach that area and curing does not occur, thereby simultaneously achieving continuity between the two patterns and prevention of boundary interference.

[0089] Finally, referring to S3006 in FIG. 3, the first pattern (10) and the second pattern (20) can be implemented on the substrate (100) as a single continuous large-area nano pattern. The formed pattern can have its surface condition adjusted as needed through residual resin removal, surface flattening, or a subsequent curing process, and is prepared to maintain a desired shape in subsequent processes.

[0090] By following this series of processes, continuous and uniform large-area nano patterns can be formed so that no seam lines occur at the boundaries, even when using multiple soft molds.

[0091] Hereinafter, a transmission region according to an embodiment of the present invention will be described with reference to FIGS. 5 and 6.

[0092] First, FIG. 5 is a drawing for explaining the structure and function of a first transparent area (313) formed on a first soft mold (310) according to one embodiment of the present invention.

[0093] Referring to FIG. 5, the first soft mold (310) includes a first pattern (10), and the first pattern (10) can be formed in the shape of a fine uneven pattern portion that transmits ultraviolet (UV) light to selectively cure the UV-curable resin underneath. This uneven pattern portion may have fine protrusions and depressions on its surface, such as a stamp.

[0094] Here, the first soft mold (310) can be manufactured by forming a cured resin layer on a film substrate that has excellent UV transmittance and flexibility, such as transparent polyimide or polydimethylsiloxane (PDMS).

[0095] At this time, the first soft mold (310) is designed considering the arrangement of the first zone (110) and the adjacent second zone (120), and the first pattern (10) may be positioned to face the first zone (110), and the first light-blocking target area (311) may correspond to the second zone (120). The first soft mold (310) is placed on the resin applied on the substrate (100), and then ultraviolet rays (arrow) are irradiated to transfer the first pattern (10) onto the substrate (100).

[0096] A first light-blocking target area (311) is formed in an area that is positioned to substantially overlap with the edge of the first soft mold (310) or the second zone (120), and a first transparent area (313) may be provided together with the first zone (110) in a portion corresponding to the first zone (110) when aligned, at a position extending from the first light-blocking target area (311) toward the first zone (110).

[0097] The first transmission area (313), unlike the open structure in which the first pattern (10) is formed, is a structure that selectively transmits only a portion of ultraviolet rays, thereby enabling selective attenuation transmission rather than full shading. This area can typically be implemented using a translucent polymer material, a fine metal thin film, or a nanostructured dot or line array pattern, and performs the function of controlling the intensity distribution of ultraviolet rays.

[0098] One of the main purposes of the first transmission area (313) is to prevent ultraviolet rays from being reflected from the surface of the lower substrate (100) and flowing into the adjacent second area (120). After passing through the opening of the first soft mold (310), the ultraviolet rays cure the resin, and some of it may be reflected back by the substrate (100) and diffused into the surrounding area.

[0099] If this reflected light reaches an uncured area where a pattern is to be formed in the next process, unintended curing may occur. The first transmission area (313) is positioned in the path of this reflected light and acts as a functional structure that controls not only direct irradiation of ultraviolet light but also curing by reflected light.

[0100] Additionally, the first transmission area (313) can form a transition area of ​​gradually decreasing density by partially irradiating ultraviolet light over the outer edge of the pattern so that the boundary of the cured pattern is not abruptly severed. This transition area can allow the two patterns to be smoothly connected when printing the second pattern (20) later.

[0101] In particular, in order to prevent physical seams between molds from being visually or functionally exposed in a method of sequentially aligning and inspecting the first soft mold (310) and the second soft mold (320), it is necessary to precisely control the roughness and pattern density distribution of the boundary area.

[0102] This first transparent area (313) can be implemented in various ways. For example, FIG. 6 illustrates a plan view of a specific embodiment of the first transparent area (313).

[0103] In the left example of FIG. 6, the first transmission area (313) is formed in the form of a plurality of parallel line patterns, configured so that ultraviolet light is partially transmitted only through the gaps between the lines. This line pattern can limit the transmittance of ultraviolet light to a certain ratio while simultaneously serving to linearly change the light intensity distribution at the boundary.

[0104] On the other hand, in the example on the right in FIG. 6, the first transmission area (313) is implemented as a dot array pattern, designed so that ultraviolet rays are transmitted as they diffuse through the gaps between the dots. The dot array method allows for uniform transmission control in various directions compared to a line pattern, and can mitigate non-uniformity caused by directionality when connecting patterns at the boundary.

[0105] Both embodiments are located on the side of the first zone (110) adjacent to the first light-blocking target area (311), and by controlling both the direct irradiation of ultraviolet rays and the influence of light reflected from the substrate (100), they can contribute to preventing a seam line from being formed at the boundary when forming the second pattern (20) thereafter.

[0106] In addition to this, it can be implemented in various shapes, and by applying a corrected metal masking design to reduce the influence of reflected light, the cured area can be aligned with the boundary line, thereby minimizing the occurrence of seam lines. In such a design, optical and physical conditions such as the thickness of the resin, the reflection path of light, the critical curing light amount, and the thickness of the soft mold can be comprehensively considered.

[0107] By adjusting the grid size, array density, and inter-cell spacing, it is possible to mitigate not only the irradiation intensity of ultraviolet rays but also optical blur that may occur at the boundaries of the irradiation area.

[0108] Such ultraviolet transmission control structures are not limited to the patterns described above. For example, the transmission area can be implemented as a circular hole, a spiral pattern, randomly distributed micro-holes, a diffraction grating structure, or a non-periodic nanopattern, and combination designs are also possible depending on the purpose. In addition, an opening may be formed in a metal thin film having ultraviolet blocking properties, or a polymer film with controlled ultraviolet absorption rate may be applied as a masking layer.

[0109] The design of the transmission area can be optimized by comprehensively considering light intensity, degree of curing, pattern thickness, reflectance of the substrate material, and refractive index of the substrate. For example, if the intensity of the irradiated ultraviolet light is high, the transmittance can be lowered to prevent over-curing, and conversely, if the irradiation is weak, the transmittance can be increased to induce sufficient curing.

[0110] FIG. 7 is a diagram illustrating a process flow for realizing a single large-area continuous pattern by sequentially forming a plurality of nano patterns according to an embodiment of the present invention. Each step includes a process of forming nano patterns in multiple steps using components such as a UV-curable resin, a masking layer (M), and a soft mold (a first mold (310), a second mold (320)).

[0111] In step S7001, a thin masking layer (M) is first applied only to the second area (120) of the substrate (100). This masking layer may be composed of a metal thin film, a light-absorbing film, or an ultraviolet reflective material, and serves to prevent curing of the area in subsequent processes. Next, an ultraviolet-curable resin is uniformly applied to the entire surface of the substrate (100). The resin can be applied using spin coating or an inkjet method, and the thickness of the masking layer is very thin so that it does not significantly affect the uniformity of the resin application.

[0112] In step S7002, a first pattern mold (310) equipped with a first pattern (10) is brought into close contact with the resin on the substrate (100), and then ultraviolet light is irradiated to transfer the pattern to the resin. Since the masking layer (M) is located in the second area of ​​the substrate (100) and shields the area from light from below, the area including the second light-shielding target area continues to harden even when irradiated with ultraviolet light, so the resin remains in a hardened state.

[0113] In another embodiment, ultraviolet rays can be irradiated from the bottom to the top of the substrate (100). In this case, the substrate (100) may be formed of a transparent material that can transmit ultraviolet rays. The ultraviolet rays pass through the substrate (100) and cure the ultraviolet-curable resin applied thereon, and a masking layer (M) is placed in the second zone so that the ultraviolet rays are blocked in that area and curing does not occur. Afterward, the uncured resin in the second zone (120) can be removed and a subsequent process can be performed.

[0114] In step S7003, the first pattern mold (310) is separated after UV irradiation.

[0115] In step S7004, the masking layer (M) installed in the initial step is removed. At this time, the masking layer is formed as a thin layer that can be removed integrally along with the cured resin located underneath, so that when removed, the cured resin in that area is also peeled off simultaneously, exposing a clean surface for subsequent pattern formation. Therefore, the masking layer may include not only a metal layer but also thin separation layers of various materials that can be removed together with the resin.

[0116] In step S7005, a masking layer (M) is formed again over the first zone (110) where the already formed first pattern (10) is located to protect it from damage or ultraviolet exposure. This masking layer is formed to cover the area while maintaining the pattern shape, and can serve to prevent deformation caused by physical contact or light irradiation during subsequent processes.

[0117] In step S7006, a UV-curable resin is applied again to the entire surface of the substrate (100). At this time, a masking layer (M) is formed on the first pattern (10) to cover the existing pattern, and the new resin is applied uniformly to the remaining area.

[0118] In step S7007, the second pattern mold (320) equipped with the second pattern (20) is precisely positioned using an alignment marker and then brought into contact with an uncured resin area. The second pattern (20) may be positioned to face the second zone (120).

[0119] In step S7008, ultraviolet light is irradiated while the second pattern mold (320) is in contact to transfer the second pattern (20) to the resin. During this process, the masking layer and the light-blocking structure prevent curing in unnecessary areas.

[0120] In step S7009, the second pattern mold (320) is separated after UV irradiation, and it can be confirmed that the second pattern (20) is formed in an adjacent area in a continuous form with the first pattern (10).

[0121] In step S7010, the masking layer (120) is finally removed so that the first pattern (10) and the second pattern (20) are completed as a seamless, continuous large-area nano pattern.

[0122] FIG. 8 is a diagram illustrating a process flow for realizing a single large-area continuous pattern by sequentially forming a plurality of nano patterns according to another embodiment of the present invention. Each step includes a process of forming a nano pattern in multiple steps using components such as a UV-curable resin, a masking layer (M), and a soft mold (a first mold (310), a second mold (320)).

[0123] In step S8001, a thin masking layer (M) is first applied only to the second area (120) of the substrate (100). This masking layer may be composed of a metal thin film, a light-absorbing film, or an ultraviolet reflective material, and serves to prevent curing of the area in a subsequent process. Next, an ultraviolet-curable resin is uniformly applied to the entire surface of the substrate (100). The resin can be applied using spin coating or an inkjet method, and the thickness of the masking layer is very thin so that it does not significantly affect the uniformity of the resin application.

[0124] In step S8002, a first pattern mold (310) having a first pattern is brought into close contact with the resin on the substrate (100), and then ultraviolet light is irradiated to transfer the pattern to the resin. Since the masking layer (M) is located in the second zone of the substrate (100) and blocks light from below, that area does not undergo curing even when irradiated with ultraviolet light.

[0125] In another embodiment, ultraviolet rays can be irradiated from the bottom to the top of the substrate (100). In this case, the substrate (100) may be formed of a transparent material that can transmit ultraviolet rays. The ultraviolet rays pass through the substrate (100) and cure the ultraviolet-curable resin applied thereon, and a masking layer (M) is placed in the second zone so that the ultraviolet rays are blocked in that area and curing does not occur. Afterward, the uncured resin in the second zone (120) can be removed and a subsequent process can be performed.

[0126] In step S8003, the first pattern mold (310) is separated after UV irradiation.

[0127] In step S8004, the masking layer (M) installed in the initial step is removed. At this time, the masking layer is removed along with the cured resin located underneath, so that the area can be exposed as a clean surface for subsequent pattern formation. Therefore, the masking layer may include not only a metal layer but also thin separation layers of various materials that can be removed along with the resin.

[0128] In step S8005, a masking layer (M) is formed on the lower surface of the first zone (110) where the already formed first pattern (10) is located, to protect it from damage or ultraviolet light exposure. This masking layer is positioned to cover the area on the lower surface of the substrate (100), thereby preventing curing by lower ultraviolet light irradiation during subsequent processes and maintaining the pattern shape.

[0129] In step S8006, a UV-curable resin is reapplied to the upper surface of the front surface of the substrate (100). The masking layer (M) blocks light from the area corresponding to the first pattern (10) on the lower surface so that the area does not harden when the lower UV is irradiated thereafter.

[0130] In step S8007, the second pattern mold (320) equipped with the second pattern (20) is precisely positioned using an alignment marker and then brought into close contact with the uncured resin area. The second pattern (20) can be positioned to face the second zone (120).

[0131] In step S8008, ultraviolet rays are irradiated from the lower surface of the substrate (100) in an upward direction to transfer the second pattern (20) onto the resin. At this time, the masking layer (M) is positioned on the lower surface corresponding to the first zone (110) to block ultraviolet rays from reaching that area.

[0132] In step S8009, the second pattern mold (320) is separated after UV irradiation, and it can be confirmed that the second pattern (20) is formed in the second zone (120) so as to be continuous with the first pattern (10).

[0133] In step S8010, the masking layer (M) formed on the lower surface of the substrate (100) is finally removed, so that the first pattern (10) and the second pattern (20) are completed as a continuous large-area nano pattern without seams.

[0134] FIG. 9 is a diagram illustrating a process of selectively applying a UV-curable resin and sequentially forming a plurality of patterns using a dispensing process, such as an inkjet method, according to another embodiment of the present invention. In this embodiment, by setting the amount and area of ​​the resin applied to each pattern forming area to be smaller than the corresponding pattern area, excessive resin flow or unintentional curing caused by reflected light can be prevented upon contact with the mold.

[0135] In step S9001, UV-curable resin is selectively applied only to the location corresponding to the first zone (110) of the substrate (100). At this time, the resin may be selectively applied only to the first zone, excluding the first offset zone adjacent to the second zone. The amount of resin applied is set to be somewhat small so as not to completely cover the entire area of ​​the first pattern (10), and the application method may include inkjet printing, a dispenser, a nozzle spraying method, etc.

[0136] In step S9002, a first pattern mold (310) containing a first pattern (10) is aligned on a substrate (100) and brought into close contact with the applied resin. At this time, the resin spreads across the entire pattern area according to the shape of the protrusions of the mold, and some of it may pass through the first offset area (indicated by an arrow) and overflow beyond the mold contact boundary to form an 'overflow area'. Ultraviolet light is irradiated from above to cure the resin according to the shape of the protrusions of the mold.

[0137] In step S9003, the first mold is removed.

[0138] In step S9004, a UV-curable resin is selectively applied to form a second pattern (20) in the second zone (120). At this time, the resin application area is set to be smaller than the second pattern formation area, excluding the second offset zone (indicated by the arrow).

[0139] In step S9005, a second pattern mold (320) including a second pattern (20) is aligned and attached to the substrate (100). The resin spreads throughout the pattern area according to the shape of the mold protrusions, and some may overflow beyond the boundary.

[0140] In the S9006 step, ultraviolet rays are irradiated from the top to cure the entire structure.

[0141] In step S9007, the second pattern mold is released to complete the state in which the first pattern (10) of the first zone (110) and the second pattern (20) of the second zone (120) are formed at their respective correct positions. The uncured resin that has spread outward can be easily removed in a subsequent cleaning process.

[0142] As such, the present invention relates to a structure and process for forming a plurality of patterns on a single substrate. The resin application method, ultraviolet irradiation conditions, alignment structure of the pattern mold, masking treatment, etc., can each be performed stepwise and can be combined in various ways as needed. This configuration can be applied when a plurality of patterns need to be formed continuously or independently.

[0143] It is obvious to those skilled in the art that the present invention may be embodied in other specific forms without departing from the spirit and essential features of the invention.

[0144] The foregoing detailed description should not be interpreted restrictively in all respects and should be considered exemplary. The scope of the invention shall be determined by a reasonable interpretation of the appended claims, and all modifications within the equivalent scope of the invention are included within the scope of the invention.

Claims

1. A method for forming a large-area nano pattern using a first mold including a first pattern and a first light-blocking target area and a second mold including a second pattern and a second light-blocking target area, A step of applying resin onto a substrate composed of adjacent first and second zones; A step of aligning the first mold such that the first pattern faces the first zone and the first light-blocking target area is located in the second zone; A step of irradiating the first aligned mold with ultraviolet light to imprint the first pattern on the first zone; A step of aligning the second mold such that the second pattern faces the second zone and the second light-blocking target area is located in the first zone; The method includes the step of irradiating ultraviolet rays onto the aligned second mold to imprint the second pattern on the second zone; A method for forming a large-area pattern using nanoimprinting, characterized in that the first pattern and the second pattern imprinted above are continuously formed to form a large-area nano pattern.

2. In Paragraph 1, A method for forming a large-area pattern using nanoimprint, characterized by including the step of applying a masking layer to the first light-blocking target area or the second light-blocking target area.

3. The first pattern and the first light-blocking target area are formed continuously, and A method for forming a large-area pattern using a nanoimprint, characterized in that the second pattern and the second light-blocking target area are formed continuously.

4. In Paragraph 1, The step of aligning the second mold above A method for forming a large-area pattern using a nanoimprint, characterized in that an alignment marker formed in the second mold is recognized by an alignment device, and the second mold is aligned so that the first pattern and the second pattern are continuous.

5. In Paragraph 1, The above first mold A method for forming a large-area pattern using a nanoimprint, characterized by including a first transmission area that extends in the direction of the first pattern from the first light-blocking target area, corresponds to the first zone when aligned, and is masked so that the ultraviolet light is partially transmitted.

6. In Paragraph 5, A method for forming a large-area pattern using nanoimprint, characterized in that the first transmission area is masked in the form of a plurality of parallel line patterns.

7. In Paragraph 5, A method for forming a large-area pattern using nanoimprint, characterized in that the first transmission area is masked in the form of a checkerboard pattern.

8. In Paragraph 5, The above first transmission area is A method for forming a large-area pattern using a nanoimprint, characterized in that the transmittance is determined based on the thickness of the resin, the reflection path of light, or the critical curing amount of the resin.

9. In Paragraph 1, The step of applying the above resin A method for forming a large-area pattern using nanoimprint, characterized by including the step of applying a masking layer to the upper surface of the second zone.

10. In Paragraph 9, A method for forming a large-area pattern using nanoimprint, characterized by further including the step of removing the masking layer together with the cured resin.

11. In Paragraph 1, A method for forming a large-area pattern using nanoimprint, characterized by further including the step of applying a masking layer to the lower surface of the above-described material.

12. In Paragraph 1, The step of applying the above resin A method for forming a large-area pattern using nanoimprint, characterized by including the step of applying resin to the first zone, excluding the first offset zone adjacent to the second zone.

13. Description consisting of adjacent Zone 1 and Zone 2; A first mold comprising a first pattern arranged to correspond to the first zone and a first light-blocking target area extending toward the second zone and limiting ultraviolet transmission; and It includes a second mold comprising a second pattern arranged to correspond to the second zone and a second light-blocking target area extending toward the first zone and limiting ultraviolet transmission, and The upper surface of the above description is Characterized by sequentially imprinting the first mold and the second mold to form a continuous large-area nano pattern of the first pattern and the second pattern. Nanoimprint mold combination for forming large-area nano patterns.

14. In Paragraph 13, On the upper surface of the first light-blocking target area Characterized by having a masking layer formed to block ultraviolet rays Nanoimprint mold combination for forming large-area nano patterns.

15. The first mold above is Characterized by including a first transmission area that extends in the direction of the first pattern in the first light-blocking target area, corresponds to the first zone when aligned on the substrate, and is masked to allow partial transmission of ultraviolet light. Nanoimprint mold combination for forming large-area nano patterns.

16. In a mold for nanoimprinting, A first pattern area with a first pattern imprinted; A first light-blocking target area extending from one side of the first pattern area to the edge of the mold; A masking layer formed in the first light-blocking target area to block ultraviolet rays Mold for nanoimprinting.

17. In Paragraph 16, Characterized by including an alignment marker recognized by an alignment device to be aligned at a predetermined position on the record. Mold for nanoimprinting.

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