Method for manufacturing imprint mold subjected to liquid repellent treatment, method for forming liquid repellent layer, and device for providing liquid repellency to mold

Abstract

To provide a method for manufacturing an imprint mold formed with a liquid repellent layer that prevents seeping and attachment of a curable composition in imprint, and a liquid repellency providing device.SOLUTION: A method for manufacturing an imprint mold subjected to liquid repellent treatment includes: a first step of forming a layer of a polymer having a fluorocarbon chain on a surface of an imprint mold; and a second step of supplying monomolecular fluorine material onto the layer of the polymer.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a method for manufacturing an imprint mold that has been treated to be liquid repellent, a method for forming a liquid repellent layer, and an apparatus for making a mold liquid repellent. [Background technology]

[0002] Photo-nanoimprinting technology has been attracting attention as a method for forming nano-sized (e.g., 1 nm or more and 1000 nm or less) fine patterns (relief structure). In photo-nanoimprinting technology, an imprint mold on which a relief pattern is formed and which is transparent to exposure light is brought into contact with a curable composition (resist) applied onto a base substrate. After the curable composition is cured to form a cured product, the mold is released from the cured product to form a cured product pattern on the base substrate. The base substrate is then processed using the cured product pattern as a mold to form a fine pattern on the base substrate. In the imprinting method, the process of forming a cured product pattern at a desired position on the wafer is repeated while moving the mold over the wafer.

[0003] Molds used in photo-nanoimprint technology are generally formed by processing quartz glass. More specifically, a convex mesa is formed on the main surface of the quartz glass substrate, and a fine uneven pattern is formed on the upper surface (top surface) of the mesa, which is the contact surface (imprint surface) with the curable composition. This uneven pattern is pressed against the curable composition. However, since the curable composition has fluidity when the upper surface of the mesa of the mold is pressed against the curable composition, the curable composition may protrude from the contact surface (imprint surface) of the upper surface of the mesa and creep up onto the side wall of the mesa. Hereinafter, this phenomenon is referred to as "seepage". The mold is separated from the cured product on the wafer when the curable composition is cured, but the curable composition that has seeped out onto the side wall of the mesa remains attached to the side wall. For this reason, when the process of pressing the mold against the curable composition is repeated, the amount of curable composition adhering to the mesa sidewall gradually increases, and eventually, this curable composition falls onto the wafer at an unintended time, causing a problem of causing major defects on the wafer (Patent Document 1).

[0004] Patent Document 1 proposes an imprint mold that prevents a curable composition from adhering to the side wall of the imprint mold. Patent Document 1 discloses a technology in which a liquid repellent material made of a liquid repellent component, a non-liquid repellent component, and a volatile solvent that dissolves the liquid repellent component is applied to the mesa side wall to form a liquid repellent layer on the mesa side wall, thereby making the mesa side wall liquid repellent to the curable composition.

[0005] However, in the liquid-repellent layer based on Patent Document 1, if the initial liquid repellency is not sufficiently high, for example, if the contact angle with respect to the curable composition is 65°, repeated imprinting may result in a decrease in liquid repellency due to slight seepage or exposure to light for curing the curable composition, and adhesion of the curable composition may not be sufficiently prevented. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Patent No. 6529843 Summary of the Invention [Problem to be solved by the invention]

[0007] Therefore, an object of the present invention is to provide a method for manufacturing an imprint mold formed with a liquid-repellent layer that suppresses adhesion due to seepage or the like of a cured composition during imprinting, and a liquid-repellent device. [Means for solving the problem]

[0008] In order to achieve the object, a method for imparting liquid repellency according to one aspect of the present invention comprises the steps of: A method for manufacturing a liquid-repellent treated imprint mold, comprising the steps of: A first step of forming a layer of a polymer having fluorocarbon chains on a surface of an imprint mold; a second step of providing a monomolecular fluorine material on said layer of polymer; The present invention is characterized by having the following. Effect of the Invention

[0009] According to the present invention, adhesion of the curable composition to the mesa sidewall can be prevented even when imprinting is performed repeatedly. [Brief description of the drawings]

[0010] [Figure 1] FIG. 1 is a diagram showing a schematic configuration of an imprint mold liquid repellent making apparatus according to an embodiment of the present invention. [Diagram 2] FIG. 2 is a cross-sectional view of an imprint mold according to an embodiment of the present invention. [Diagram 3] 13 shows contact angle data when a film is formed by stacking a polymer having a fluorocarbon chain according to an embodiment of the present invention and a monomolecular fluorine material. [Figure 4] 1 is a schematic configuration of a liquid repellent layer forming apparatus according to an embodiment of the present invention. [Diagram 5] 4A to 4C are top views of an imprint mold in a liquid-repellent layer coating method according to an embodiment of the present invention. [Figure 6]1 is an imprint method according to an embodiment of the present invention. [Figure 7] Seepage height calculation model. [Figure 8] Seepage height calculation results. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings as appropriate. However, the present invention is not limited to the embodiment described below. In addition, in the present invention, modifications and improvements to the embodiment described below based on the ordinary knowledge of a person skilled in the art are also included in the scope of the present invention, as long as they do not deviate from the gist of the present invention.

[0012] (First embodiment) <Configuration of the liquid repellent device> As shown in FIG. 1, an imprint mold liquid repellent apparatus according to one embodiment includes a stage (102) that supports a mold (101), a supply head (103) that supplies liquid repellent material, a movement mechanism (104) for relatively moving the supply head and the stage, and a control unit that is electrically connected to each component and controls the driving.

[0013] The control section includes a microcomputer that centrally controls each section, and a storage section that stores processing information such as supply processing, transport processing, and the like, various programs, and the like.

[0014] <Mold shape> Molds used in nanoimprinting are formed so that the contact surface of the mold has surrounding sidewall surfaces and protrudes (projects) from the mold base material so that the substrate (wafer) and the mold substrate other than the contact surface (imprint surface) do not come into contact with the substrate (wafer) even if the parallelism between the mold and the substrate (wafer) is not perfect. The convex portion where the contact surface is formed, i.e., the plateau portion formed by the sidewall surface and the contact surface as the upper surface, is called a mesa portion.

[0015] With this configuration, a certain clearance is maintained between the surface of the mold other than the imprint surface and the substrate to be processed during imprinting, preventing the two from coming into contact with each other.

[0016] Fig. 2 is a cross-sectional view of a typical imprint mold in the present invention. The shape of the mold of the present invention will be described below with reference to Fig. 2. When the mold (101) is pressed against the curable composition (107) on the wafer (106), a treatment is performed to form a liquid-repellent surface against organic substances on the side wall of the mold (101) so that the curable composition (107), which is an organic material, does not creep up on the side wall of the mold (101).

[0017] The following mainly describes the form of forming a liquid-repellent layer having a liquid-repellent surface. The liquid-repellent layer (108) is a film (liquid-repellent layer) that has a higher contact angle with the curable composition (107) than the surface material of the mold on which the liquid-repellent layer (108) is formed, such as quartz. The material and method of forming the liquid-repellent layer (108) will be described later.

[0018] As shown in FIG. 2, the imprint mold (101) according to this embodiment has a mesa portion (a protruding pattern forming portion) (101a), and a fine concave-convex pattern (101b) is formed on the lower surface (imprint surface) of the mesa portion (101a). By pressing this concave-convex pattern (101b) against the curable composition (107) on the wafer (106), the concave-convex pattern (101b) is transferred to the curable composition (107), forming a curable composition pattern (107a). In order to prevent the curable composition (107) from protruding outside the imprint surface and creeping up and adhering to the side wall of the mold (101) when the concave-convex pattern (101b) of the mold (101) is pressed against the curable composition (107), a liquid repellent layer (108) is formed on the side wall of the mold (101). This liquid repellent layer (108) may be formed not only on the sidewall of the mesa portion (101a) but also on the sidewall of the base portion (101c) of the substrate supporting the mesa portion (101a).

[0019] More specifically, the base portion (101c) has a first surface (101e) connected to the sidewall of the mesa portion (101a) and extending in a direction intersecting from the sidewall (101d) of the mesa portion (101a), and a second surface (101f) connected to the first surface (101e) and extending in a direction intersecting from the first surface (101e), and both the first surface (101e) and the second surface (101f) are provided with a liquid-repellent layer (108). In this manner, the liquid-repellent layer (108) may be formed on the entire sidewall of the mold (101).

[0020] When forming the liquid-repellent layer (108) on the side wall of the mold (101), it is necessary to avoid forming a liquid-repellent layer on the imprinted surface (101g). If a liquid-repellent layer is formed on the imprinted surface, there is a risk of a non-filling defect of the curable composition occurring. Note that even on the imprinted surface, it may be acceptable for the liquid-repellent layer to exist within a range of width of several μm to several mm at the outer periphery.

[0021] <Liquid-repellent layer material> The liquid repellent layer (108) is mainly composed of a polymer having a fluorocarbon chain and a monomolecular fluorine material.

[0022] These materials have a high contact angle with the cured composition (107) and can form a good liquid-repellent layer. The polymer having a fluorocarbon chain is preferably an acrylic polymer having a perfluoroalkyl group having 4 to 8 carbon atoms in the side chain. The monomolecular fluorine material is preferably a monomolecular fluorine material having a perfluoropolyether group in the main chain. These materials may have a functional group depending on the application. Examples include a hydroxyl group, a formyl group, a carboxyl group, a carbonyl group, an amino group, and an alkoxysilyl group.

[0023] The polymer having a fluorocarbon chain and the monomolecular fluorine material are each dissolved in a volatile solvent and supplied (applied) as a liquid repellent material. The volatile solvent is not particularly limited as long as it is a volatile solvent that dissolves the polymer having a fluorocarbon chain and the monomolecular fluorine material. When forming the repellent material, the volatile solvent is evaporated, so a low boiling point is desirable for rapid evaporation, but if the boiling point of the polymer having a fluorocarbon chain is too low, the polymer having a fluorocarbon chain will solidify at the tip of the supply head, making it impossible to apply stably. The boiling point is preferably 50 to 140°C, more preferably 60 to 100°C.

[0024] <Liquid repellent material concentration and layered film formation> If the solids concentration of the liquid repellent material containing a polymer having a fluorocarbon chain that forms the liquid repellent layer (108) is too high, the formed polymer having a fluorocarbon chain may peel off from the imprint mold (101) or may segregate to become foreign matter. For this reason, the solids concentration of the liquid repellent material containing a polymer having a fluorocarbon chain is preferably 0.1% by weight or less, but depending on the material of the liquid repellent material and the material of the imprint mold (101), 0.01% by weight or less is preferable.

[0025] On the other hand, if the solid content concentration of the liquid repellent material containing a polymer with a fluorocarbon chain is too low, it does not exhibit sufficient liquid repellency. When the solid content concentration of the liquid repellent material containing a polymer with a fluorocarbon chain is low, it is possible to improve the liquid repellency by forming a film by overlapping monomolecular fluorine materials. As shown in Figure 3, when a film is formed by only forming a film of a polymer with a fluorocarbon chain and when a film is formed by overlapping monomolecular fluorine materials, there is a significant difference in liquid repellency when the solid content concentration of the liquid repellent material containing a polymer with a fluorocarbon chain is 0.02 wt% or less. When a film is formed by overlapping monomolecular fluorine materials, sufficient liquid repellency is exhibited even when the solid content concentration of the liquid repellent material containing a polymer with a fluorocarbon chain is 0.0075 wt%. Furthermore, when a film is formed by overlapping monomolecular fluorine materials, peeling or foreign matter does not occur, unlike polymers with fluorocarbon chains. However, sufficient liquid repellency cannot be obtained by using only monomolecular fluorine materials.

[0026] <Liquid repellent device> As shown in FIG. 4, in addition to the supply head (103), the liquid repellent device is equipped with a treatment chamber (109) for treating the mold (101), a stage (102) on which the untreated mold (101) is placed, the supply head (103), and a movement mechanism (104) for moving the supply head (103) in the X-axis, Y-axis, and Z-axis directions.

[0027] The supply head (103) is a dispenser that dispenses liquid repellent material. This supply head (103) stores the liquid repellent material supplied from a tank (110) outside the processing chamber (109) and dispenses the stored liquid repellent material toward the mold (101) on the stage (102) at a predetermined timing. The supply head (103) is electrically connected to the control unit (111) and its drive is controlled by the control unit (111).

[0028] The processing chamber (109) is formed in a box shape so as to be capable of accommodating the supply head (103), the stage (102), the moving mechanism (104), and the like. A filter device (112) having a filter attached thereto for removing foreign matter from the air is provided on the upper surface of the processing chamber, and an exhaust port (113) is provided on the lower surface (bottom surface) of the processing chamber (109). Air in the processing chamber (109) flows from the filter in the filter device to the exhaust port (113), and the inside of the processing chamber (109) is kept clean by a downflow (vertical laminar flow). As the filter, for example, a ULPA filter or a HEPA filter can be used.

[0029] The moving mechanism (102) supports a supply head (103) and moves the supply head (103) relative to the stage (102). The moving mechanism includes mechanisms for movement in the X-axis, Y-axis, and Z-axis directions, each of which operates independently. Various types of moving mechanisms can be used, such as a linear motor type moving mechanism, an air stage type moving mechanism, or a feed screw type moving mechanism.

[0030] <Development of a liquid repellent device> The liquid repellent device can be introduced as a device that makes the mesa sidewall of the mold liquid repellent by attaching a transport mechanism, a load unit, an unload unit, etc. Also, by adding it to a mold cleaning device or a NIL exposure device, it is possible to add the function of making the mesa sidewall of the mold liquid repellent to the functions of the device.

[0031] <Method for forming a liquid-repellent layer and method for manufacturing a liquid-repellent mold> A method for forming a liquid-repellent layer and a method for producing an imprint mold that has been treated to be liquid-repellent will be described below.

[0032] First, a method for forming a liquid-repellent layer on the mesa sidewalls on the mold (101) in the configuration shown in FIG. 4 will be described.

[0033] In a first step, the supply head (103) is maintained at a predetermined height and moved by the movement mechanism (104) along application paths P1 to P5 on the main surface (101e) shown in Fig. 5, thereby continuously supplying liquid repellent material to the first surface (101e) on the mold (101) on the stage (102). As described above, a solution containing a polymer having a fluorocarbon chain is used as the liquid repellent material.

[0034] The application paths P1 to P5 move in the order of P1, P2, P3, P4, and P5 along the outer periphery of the imprint surface (101g) on ​​the first surface (101e). The application paths are separated from the imprint surface (101g) by a predetermined distance L (e.g., 1 mm). P1 is the discharge start position, and P5 is the discharge stop position. The area applied by this application path becomes, for example, a frame shape surrounding the imprint surface (101g). The liquid repellent material applied by this application path spreads due to its wettability and reaches the side wall portion (101d) of the mesa portion. At this time, the liquid repellent material that spreads does not reach the imprint surface (101g) by climbing over the side wall of the mesa portion (101) due to surface tension, but instead adheres to the side surface. Thereafter, when the volatile solvent contained in the liquid repellent material evaporates and dries, a liquid repellent layer (108) containing a polymer having a fluorocarbon chain as a liquid repellent component is formed as a continuous film at least on the mesa sidewall portion (101d) shown in Fig. 2. At this time, no liquid repellent layer is formed on the imprint surface (101g).

[0035] Then, in the second step, a monomolecular fluorine material is layered on the polymer having a fluorocarbon chain to form a film. The method of film formation may be the same as that of the first step, and a layered film containing a monomolecular fluorine material is formed by applying a liquid repellent solution containing a monomolecular fluorine material and drying it after the volatile solvent has evaporated. In this case, the path for applying the liquid repellent material containing a monomolecular fluorine material may be the same as the path for applying the liquid repellent material containing a polymer having a fluorocarbon chain, but the distance L may be changed depending on the physical properties of the liquid repellent material. Furthermore, the liquid repellent material containing a monomolecular fluorine material may be partially applied to a portion where the liquid repellency of the polymer having a fluorocarbon chain is particularly poor. For example, the corner of (101g) is likely to be thinly formed with the polymer having a fluorocarbon chain, and the liquid repellency may be poorer than other portions, so the liquid repellent material containing a monomolecular fluorine material may be applied discretely to P2, P3, P4, and P5, or the amount of application may be increased relatively compared to other regions.

[0036] In addition, the coating paths P1 to P5 used in this description are only examples, and the start and stop positions are not important as long as the paths can be formed into a frame shape surrounding the imprint surface (101g), and the paths do not have to be coated continuously. If the paths are not coated continuously, the coating can be devised so that there are no uncoated areas on the paths.

[0037] As described above, by subjecting an imprint mold made of a pure base such as a quartz glass substrate to a liquid repellent treatment, an imprint mold on which a liquid repellent layer is formed can be manufactured.

[0038] <Imprint method> Next, each step of the imprint method according to this embodiment will be described with reference to the schematic cross-sectional views of FIG.

[0039] The cured film of the curable composition obtained by the imprinting method according to this embodiment is preferably a film having a pattern of 1 nm or more and 10 mm or less in size. Generally, a pattern forming technique for producing a film having a nano-sized (1 nm or more and 1000 nm or less) pattern (relief structure) by utilizing light is called a photo-nanoimprinting method. The imprinting method according to this embodiment utilizes the photo-nanoimprinting method. Each step will be described below.

[0040] (Lamination process [1]) As an example of this step (lamination step [1]), as shown in FIG. 6, droplets of the curable composition (202) are discretely dropped and arranged on the substrate (201). The inkjet method is particularly preferable as an arrangement method. The droplets of the curable composition (202) are arranged densely on the substrate facing the region on the mold where recesses are densely present, and sparsely on the substrate facing the region on the mold where recesses are sparsely present. This makes it possible to control the residual film, which will be described later, to a uniform thickness regardless of the density of the pattern on the mold.

[0041] The dropped droplet gradually spreads over the substrate surface over time. The arrow (203) indicates the direction in which the droplet spreads.

[0042] As another example of this step (lamination step [1]), the curable composition (202) may be disposed on the substrate (201) by using a spin coating method. In this case, the curable composition (202) is continuously disposed on the substrate (201).

[0043] The viscosity of the mixture of components excluding the solvent of the curable composition (202) according to this embodiment at 25°C is preferably 1 mPa·s or more and less than 40 mPa·s. More preferably, it is 1 mPa·s or more and less than 20 mPa·s. If the viscosity of the curable composition (202) exceeds 40 mPa·s, it becomes impossible to apply the composition by the inkjet method, which can make the remaining film thickness uniform and form a high-precision pattern by disposing droplets discretely according to the coarseness and density of the desired pattern. If the viscosity is lower than 1 mPa·s, the composition may flow when applied (disposed), causing uneven application, or the composition may flow out from the edge of the mold in the contact step described later, which is not preferable.

[0044] The surface tension of the curable composition (202) according to this embodiment is preferably 5 mN / m or more and 70 mN / m or less at 23°C for the composition of components excluding the solvent. More preferably, it is 7 mN / m or more and 50 mN / m or less, and even more preferably, it is 10 mN / m or more and 40 mN / m or less. Here, the higher the surface tension, for example, 5 mN / m or more, the stronger the capillary force, so that when the curable composition (202) is brought into contact with the mold, filling (spreading and filling) is completed in a short time. In addition, by setting the surface tension to 70 mN / m or less, the cured film obtained by curing the curable composition becomes a cured film having surface smoothness.

[0045] The contact angle of the curable composition (202) according to this embodiment with respect to the imprint surface and the substrate surface is preferably 0° or more and 100° or less for a composition of components excluding the solvent. If the contact angle is greater than 100°, the capillary force acts in the negative direction (the direction that shrinks the contact interface between the mold and the curable composition) inside the mold pattern or in the gap between the substrate and the mold, and filling does not occur. It is particularly preferable that the contact angle is 0° or more and 30° or less. The lower the contact angle, the stronger the capillary force acts, and the faster the filling speed.

[0046] The substrate (201) on which the curable composition (202) is placed is a substrate to be processed, and is usually a silicon wafer. A layer to be processed may be formed on the substrate (201). Another layer may be formed between the substrate (201) and the layer to be processed. If a quartz substrate is used as the substrate (201), a replica (mold replica) of a quartz imprint mold can be produced.

[0047] However, the substrate (201) is not limited to a silicon wafer or a quartz substrate, and may be any substrate known for use in semiconductor devices, such as aluminum, titanium-tungsten alloy, aluminum-silicon alloy, aluminum-copper-silicon alloy, silicon oxide, silicon nitride, etc.

[0048] The surface of the substrate (201) (substrate to be processed) or the layer to be processed may be subjected to a surface treatment such as silane coupling treatment, silazane treatment, or formation of an organic thin film to improve adhesion to the curable composition (202).

[0049] (Mold contact process [2]) Next, as shown in Figure 6 [2], [3], and [4], the imprint mold (204) having a prototype pattern for transferring the pattern shape is brought into contact with the curable composition (202) formed in the previous step (lamination step [1]). As a result, the curable composition (202) fills the recesses of the fine pattern on the surface of the mold (204), forming a liquid film that fills the fine pattern of the mold. Here again, the arrow (203) indicates the direction in which the droplets (curable composition) spread (fill the recesses).

[0050] As the mold (204), it is preferable to use a mold (204) made of a light-transmitting material in consideration of the next process (light irradiation process). As the material constituting the mold (204), specifically, glass, quartz, light-transmitting resin such as PMMA or polycarbonate resin, transparent metal deposition film, flexible film such as polydimethylsiloxane, photocured film, metal film, etc. are preferable as the base material. However, when using a light-transmitting resin as the material constituting the mold (204), it is necessary to select a resin that is not dissolved in the components contained in the curable composition (202). Quartz is particularly preferable as the material constituting the mold (204) because it has a small thermal expansion coefficient and small pattern distortion.

[0051] The fine pattern on the surface of the mold (204) preferably has a pattern height of 4 nm or more and 200 nm or less. The lower the pattern height, the lower the force required to peel the mold from the photocured film of the curable composition in the demolding step, i.e., the demolding force, and the fewer demolding defects remaining on the mold side due to the curable composition pattern being torn off during demolding. When the mold is peeled off, the elastic deformation of the curable composition pattern due to the impact may cause adjacent curable composition patterns to come into contact with each other, resulting in adhesion or damage to the curable composition patterns. However, if the pattern height is about twice or less the pattern width (aspect ratio 2 or less), it is highly likely that such problems can be avoided. On the other hand, if the pattern height is too low, the processing accuracy of the substrate to be processed is low.

[0052] As described above, the present invention also includes the case where a mold that does not have a fine pattern on the imprint surface is used for the purpose of obtaining a flat surface for the curable composition.

[0053] In order to improve the releasability between the photocured curable composition (202) and the surface of the mold (204), the mold (204) may be subjected to a surface treatment before the main step, which is a mold contact step between the curable composition (202) and the mold (204). As a method of surface treatment, a method of forming a release agent layer by applying a release agent to the surface of the mold (204) may be mentioned. Here, examples of the release agent applied to the surface of the mold (204) include silicone-based release agents, fluorine-based release agents, hydrocarbon-based release agents, polyethylene-based release agents, polypropylene-based release agents, paraffin-based release agents, montan-based release agents, and carnauba-based release agents. For example, commercially available coating-type release agents such as Optool (registered trademark) DSX manufactured by Daikin Industries, Ltd. may also be suitably used. The release agents may be used alone or in combination of two or more. Among these, fluorine-based and hydrocarbon-based release agents are particularly preferred.

[0054] In this step (mold contact step), as shown in Fig. 6 [2], when the mold (104) and the curable composition (202) are brought into contact with each other, the pressure applied to the curable composition (202) is not particularly limited. The pressure may be 0 MPa or more and 100 MPa or less. The pressure is preferably 0 MPa or more and 50 MPa or less, more preferably 0 MPa or more and 30 MPa or less, and even more preferably 0 MPa or more and 20 MPa or less.

[0055] In the mold contact step, the time for contacting the mold with the curable composition (202) is not particularly limited, but may be, for example, 0.1 to 600 seconds. The time is preferably 0.1 to 3 seconds, and more preferably 0.1 to 1 second. If it is shorter than 0.1 seconds, the spread and fill are insufficient, and defects called unfilled defects tend to occur frequently.

[0056] The mold contact step can be carried out under any of the conditions of air, reduced pressure, and inert gas atmosphere, but it is preferable to use a reduced pressure atmosphere or an inert gas atmosphere as an atmosphere control gas, since this can prevent the influence of oxygen and moisture on the curing reaction. Specific examples of inert gases that can be used when carrying out this step under an inert gas atmosphere include nitrogen, carbon dioxide, helium, argon, various fluorocarbon gases, and the like, or mixed gases thereof. When carrying out this step under an atmosphere of a specific gas, including air, the preferred pressure is 0.0001 atm or more and 10 atm or less.

[0057] (Light irradiation process [3]) Next, as shown in Fig. 6[3], the curable composition (202) is irradiated with light (205) through a mold (204). More specifically, the curable composition (202) filled in the fine pattern of the mold (204) is irradiated with light (205) through the mold (204). As a result, the curable composition (202) filled in the fine pattern of the mold (104) is cured by the irradiated light (205) to become a cured film (206) having the pattern shape.

[0058] Here, the irradiation light (205) to be irradiated to the curable composition (202) filled in the fine pattern of the mold (204) is selected according to the sensitivity wavelength of the curable composition (202). Specifically, it is preferable to appropriately select and use ultraviolet light having a wavelength of 150 nm or more and 400 nm or less, X-rays, electron beams, etc.

[0059] Among these, ultraviolet light is particularly preferred as the irradiation light (205). This is because many of the compounds commercially available as curing assistants (photopolymerization initiators) are sensitive to ultraviolet light. Examples of light sources that emit ultraviolet light include high-pressure mercury lamps, ultra-high-pressure mercury lamps, low-pressure mercury lamps, deep-UV lamps, carbon arc lamps, chemical lamps, metal halide lamps, xenon lamps, KrF excimer lasers, ArF excimer lasers, and F2 excimer lasers, with ultra-high-pressure mercury lamps being particularly preferred. The number of light sources used may be one or more. When light irradiation is performed, it may be performed on the entire surface of the curable composition (202) filled in the fine pattern of the mold, or only on a partial area.

[0060] The light irradiation process may be performed intermittently multiple times over the entire region of the substrate, or may be performed continuously over the entire region. Furthermore, a part of region A may be irradiated in a first irradiation process, and a part of region B different from region A may be irradiated in a second irradiation process.

[0061] (Mold release process [4]) Next, the cured film (206) having the pattern shape is separated from the mold (204). In this step (mold release step), as shown in FIG. 6[4], the cured film (206) having the pattern shape is separated from the mold (204), and a free-standing cured film (206) having a pattern shape that is a reverse pattern of the fine pattern formed on the mold (204) in step [3] (light irradiation step) is obtained. Note that the cured film remains in the recesses of the concave-convex pattern of the cured film (206) having the pattern shape, and this film will be referred to as a residual film (207).

[0062] When the mold contact step is performed in a condensable gas atmosphere, when the cured film (206) and the mold (204) are separated in the demolding step, the condensable gas evaporates as the pressure at the interface where the cured film (206) and the mold (204) come into contact decreases. This tends to have the effect of reducing the demolding force required to separate the cured film (206) and the mold (204).

[0063] The method for separating the patterned cured film (206) from the mold (204) is not particularly limited as long as a part of the patterned cured film (206) is not physically damaged during the separation, and various conditions are also not particularly limited. For example, the substrate (201) (substrate to be processed) may be fixed and the mold (204) may be moved away from the substrate (201) to separate them. Alternatively, the mold (204) may be fixed and the substrate (201) may be moved away from the mold (104) to separate them. Alternatively, both of them may be pulled in opposite directions to separate them.

[0064] By continuously performing the above steps [1] to [4] on multiple shot areas, a cured film having a desired concave-convex pattern shape (a pattern shape resulting from the concave-convex shape of the mold 204) can be obtained at a desired position on the substrate.

[0065] <Calculation of seepage height> In order to show the effect of suppressing seepage of the liquid-repellent imprint mold of this embodiment, the following calculation was performed. In a model as shown in FIG. 7, the relationship between the contact angle (θm) of the curable composition on the liquid-repellent layer surface and the seepage height was theoretically calculated. For simplicity in the calculation, the mold was approximated as a flat, cylindrical rigid body, the substrate was also approximated as a flat rigid body, and the curable composition was approximated as a Newtonian fluid. The mold surface was a flat surface without a concave-convex pattern. A lubrication approximation was applied to the curable composition, and the load applied to the mold (F) was zero N, the mesa area (A) was 858 mm2, the initial liquid film thickness (h) of the curable composition was 15 nm, and the physical properties of the curable composition were viscosity (μ) of 5 mPa·s, surface tension (γ) of 30 mN / m, and substrate contact angle (θs) of 0°. The seepage height (Lm) after 1 second was calculated when the contact angle (θm) on the liquid-repellent layer surface was 0 to 90°.

[0066] The calculation results are shown in FIG. 8. Even if the applied load (F) is zero N, the mold is pulled toward the substrate by the meniscus force generated by the meniscus between the mold and the substrate, and the squeeze effect caused by the mold descent causes the behavior of the occurrence of seepage, which could be quantitatively calculated. The seepage height (Lm) was significantly lower when the contact angle (θm) on the liquid-repellent layer surface was 5° or more than when it was 0°, was about 55% at 30°, was about 10% at 70°, and was zero nm at 90°. The above calculations showed that the liquid-repellent layer of the present invention improves seepage, and was particularly effective when the contact angle was 70° or more and less than 100°.

[0067] (Embodiment relating to an article manufacturing method) The method for manufacturing an article according to an embodiment of the present invention is suitable for manufacturing an article such as a microdevice such as a semiconductor device or an element having a fine structure. The method for manufacturing an article according to this embodiment includes a step of forming a pattern on an imprint material applied to a substrate using an imprinting device capable of using the above-mentioned mold (a step of performing an imprinting process on the substrate), and a step of processing the substrate on which the pattern has been formed in this step. Furthermore, this manufacturing method includes other well-known steps (oxidation, film formation, deposition, doping, planarization, etching, resist stripping, dicing, bonding, packaging, etc.). The method for manufacturing an article according to this embodiment is advantageous in at least one of the performance, quality, productivity, and production cost of the article compared to conventional methods.

[0068] The pattern of the cured product formed using the imprinting apparatus is used permanently on at least a part of various articles, or temporarily when manufacturing various articles. The articles include electric circuit elements, optical elements, MEMS, recording elements, sensors, molds, etc. Examples of electric circuit elements include volatile or non-volatile semiconductor memories such as DRAM, SRAM, flash memory, and MRAM, and semiconductor elements such as LSI, CCD, image sensors, and FPGAs. Examples of molds include molds for imprinting.

[0069] The pattern of the cured product is used as it is as at least a part of a component of the article, or is used temporarily as a resist mold, which is removed after etching or ion implantation is performed in a substrate processing step. EXAMPLES

[0070] The present invention will now be described in more detail with reference to examples.

[0071] Example 1 A liquid-repellent layer was formed by the above-mentioned method for forming a liquid-repellent layer, and a liquid-repellent treated imprint mold was manufactured. The polymer having a fluorocarbon chain was prepared by dissolving a polymer having a perfluoroalkyl group, which is carbon chain 6, in a volatile solvent at a solid content concentration of 0.001 wt%. After the solvent was sufficiently evaporated and a film of the polymer having a fluorocarbon chain was formed, a monomolecular fluorine material having a perfluoropolyether group in the main chain was dissolved in a volatile solvent and layered on the polymer having a fluorocarbon chain to form a film of the monomolecular fluorine material.

[0072] After the liquid-repellent layer was formed, the curable composition (resist) was dropped onto the sidewall of the mold before curing, and the contact angle was measured. The contact angle was 73°, which showed sufficient liquid repellency. The contact angle was measured using DropMeasure-1000 manufactured by Microjet Co., Ltd.

[0073] In addition, the surface of the mold after the liquid-repellent layer was formed was observed, and it was confirmed that the liquid-repellent film formed on the side wall of the mesa portion had no peeling or foreign matter.

[0074] <Summary of the embodiment> The disclosure herein includes an imprinting apparatus, an imprinting method, and an article manufacturing method.

[0075] (Item 1) A method for manufacturing a liquid-repellent treated imprint mold, comprising the steps of: A first step of forming a layer of a polymer having fluorocarbon chains on a surface of an imprint mold; a second step of providing a monomolecular fluorine material on said layer of polymer; A method for producing a liquid-repellent treated imprint mold, comprising the steps of:

[0076] (Item 2) The imprint mold comprises: 2. The manufacturing method according to item 1, comprising a substrate having a main surface and a mesa portion provided on the main surface, the mesa portion having a top surface formed with a concave-convex pattern that comes into contact with the curable composition.

[0077] (Item 3) 3. The manufacturing method according to item 2, wherein the polymer layer is formed on at least the side surface of the mesa portion.

[0078] (Item 4) 4. The manufacturing method according to item 3, wherein the polymer layer is not formed in the region where the concave-convex pattern is formed on the top surface of the mesa portion.

[0079] (Item 5) the first step is a step of applying a solution containing a polymer having a fluorocarbon chain; 5. The method according to any one of items 1 to 4, wherein the second step is a step of applying a solution containing a monomolecular fluorine material onto the polymer layer.

[0080] (Item 6) the first step is a step of applying a solution containing a polymer having a fluorocarbon chain to form a continuous film of the polymer on a side surface of the mesa portion; 6. The method according to any one of items 3 to 5, wherein the second step is a step of applying a solution containing a monomolecular fluorine material onto the polymer film to form a laminated film.

[0081] (Item 7) 7. The method according to any one of items 1 to 6, wherein the polymer having a fluorocarbon chain is an acrylic polymer having a perfluoroalkyl group having 4 to 8 carbon atoms in a side chain.

[0082] (Item 8) 8. The method according to any one of items 1 to 7, wherein the monomolecular fluorine material is a fluorine material having a perfluoropolyether group in the main chain.

[0083] (Item 9) 9. The method according to any one of items 3 to 8, wherein a contact angle of the layer formed on the side surface of the mesa portion with respect to the curable composition is 70° or more and less than 100°.

[0084] (Item 10) 10. The manufacturing method according to any one of items 6 to 9, wherein the application of the monomolecular fluorine material in the second step is performed on a corner of the mesa portion.

[0085] (Item 11) A method for forming a liquid-repellent layer on a surface of an imprint mold, comprising the steps of: A first step of forming a layer of a polymer having a fluorocarbon chain on the surface; a second step of providing a monomolecular fluorine material on said layer of polymer; A method for forming a liquid-repellent layer, comprising:

[0086] (Item 12) 1. A mold liquid repellent apparatus for making an imprint mold liquid repellent, the imprint mold having a base having a main surface and a mesa portion provided on the main surface, the mesa portion having a top surface on which a concave-convex pattern that comes into contact with a curable composition is formed, the apparatus comprising: a stage supporting the mold; a supply head for supplying a liquid repellent material to the mold; a moving mechanism for moving the stage and the supply head relative to each other; a control unit that controls the supply head and the movement mechanism so that the supply head supplies the liquid repellent material to a side surface of the mesa portion, The supply head is configured to be capable of applying a solution containing a polymer having a fluorocarbon chain and a solution containing a monomolecular fluorine material. A mold liquid repellent device comprising:

[0087] (Item 13) Item 13. The mold liquid repellent apparatus according to item 12, wherein the supply head supplies the monomolecular fluorine material only to the corners of the mesa portion. [Explanation of symbols]

[0088] 101 Mold 101a Mesa portion (protruding pattern forming portion) 101b Fine uneven pattern on imprint surface 101c Base 101d Mesa side wall 101e Front page 101f Second side 101g Imprint surface 102 Stages 103 Supply Head 104 Moving mechanism 106 Wafers 107 Curable composition 107a Curable composition pattern 108 Liquid repellent layer 109 Processing Room 110 Tank 111 Control section 112 Filter device 113 Exhaust port 201 Substrate 202 Curable composition 203 Spreading direction of droplets 204 Mold 205 Irradiation Light 206 Patterned cured film 207 Remaining membrane

Claims

1. A method for manufacturing a liquid-repellent treated imprint mold, comprising the steps of: A first step of forming a layer of a polymer having fluorocarbon chains on a surface of an imprint mold; a second step of providing a monomolecular fluorine material on said layer of polymer; A method for producing a liquid-repellent treated imprint mold, comprising the steps of:

2. The imprint mold comprises:

2. The method according to claim 1, further comprising a substrate having a main surface and a mesa portion provided on the main surface, the mesa portion having a top surface formed with a concave-convex pattern that comes into contact with the curable composition.

3. The manufacturing method according to claim 2 , further comprising forming the polymer layer on at least a side surface of the mesa portion.

4. The method according to claim 3 , wherein the polymer layer is not formed in an area where the concave-convex pattern is formed on the top surface of the mesa portion.

5. the first step is a step of applying a solution containing a polymer having a fluorocarbon chain; The method according to claim 1 , wherein the second step is a step of applying a solution containing a monomolecular fluorine material onto the polymer layer.

6. the first step is a step of applying a solution containing a polymer having a fluorocarbon chain to form a continuous film of the polymer on a side surface of the mesa portion; 4. The method according to claim 3, wherein the second step is a step of forming a laminated film by applying a solution containing a monomolecular fluorine material onto the polymer film.

7. 2. The method according to claim 1, wherein the polymer having a fluorocarbon chain is an acrylic polymer having a perfluoroalkyl group having 4 to 8 carbon atoms in a side chain.

8. 2. The method according to claim 1, wherein the monomolecular fluorine material is a fluorine material having a perfluoropolyether group in the main chain.

9. 4. The method according to claim 3, wherein the layer formed on the side surface of the mesa portion has a contact angle with the curable composition of 70° or more and less than 100°.

10. 7. The method according to claim 6, wherein the application of the monomolecular fluorine material in the second step is performed on corners of the mesa portion.

11. A method for forming a liquid-repellent layer on a surface of an imprint mold, comprising the steps of: A first step of forming a layer of a polymer having fluorocarbon chains on the surface; a second step of providing a monomolecular fluorine material on said layer of polymer; A method for forming a liquid-repellent layer, comprising:

12. 1. A mold liquid repellent apparatus for making an imprint mold liquid repellent, the imprint mold having a base having a main surface and a mesa portion provided on the main surface, the mesa portion having a top surface on which a concave-convex pattern that comes into contact with a curable composition is formed, the apparatus comprising: a stage supporting the mold; a supply head for supplying a liquid repellent material to the mold; a moving mechanism for moving the stage and the supply head relative to each other; a control unit that controls the supply head and the movement mechanism so that the supply head supplies the liquid repellent material to a side surface of the mesa portion, the supply head is configured to be capable of applying a solution containing a polymer having a fluorocarbon chain and a solution containing a monomolecular fluorine material; A mold liquid repellent device comprising:

13. 13. The mold liquid repellent apparatus according to claim 12, wherein the supply head supplies the monomolecular fluorine material only to corners of the mesa portion.

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